You searched for subject:(selectivity).
Showing records 1 – 30 of
779 total matches.
◁ [1] [2] [3] [4] [5] … [26] ▶
University of Illinois – Chicago
1.
Giri, Janhavi.
Study of Selectivity and Permeation in Voltage-Gated Ion Channels.
Degree: 2012, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/8181 
► Ion channels are proteins with holes down their middle that regulate access to biological cells and are responsible for an enormous range of biological functions.…
(more)
▼ Ion channels are proteins with holes down their middle that regulate access to biological cells and are responsible for an enormous range of biological functions. A substantial fraction of the drugs used in clinical medicine are targeted directly or indirectly on channels. Ion
selectivity and permeation are based on simple laws of physics and chemistry. Ion channels are therefore ideal candidates for physical investigation. A reduced model generates the
selectivity of voltage-gated L-type calcium channel (crystal structure not known) under a wide range of ionic conditions using only two parameters with unchanging values. The reasons behind the success of this reduced model are investigated since chemical intuition suggests that more detailed models are needed. Monte Carlo simulations are performed investigating the role of flexibility of the side chains in the
selectivity of calcium channels under a wide range of ionic conditions. Results suggest that the exact location and mobility of oxygen ions have little effect on the
selectivity behavior of calcium channels. The first order determinant of
selectivity in calcium channels is the density of charge in the
selectivity filter. Flexibility seems a second order determinant. Single channel planar lipid bilayer experiments are performed to determine the
selectivity, permeation, and sialic acid specificity of a bacterial outer-membrane channel NanC of Escherichia Coli with a known crystal structure. Measurements show that NanC exhibits a large unit conductance varying with the applied voltage polarity, anion over cation
selectivity, and voltage-dependent gating. Unitary conductance of NanC decreases significantly in presence of the buffer HEPES. Alternate buffers are tested. Results suggest that the sialic acid specificity of NanC should be performed in low concentration salt solutions (250 mM) without pH buffers adjusted to neutral pH 7.0. Neu5Ac (a major sialic acid) is observed to change the gating and considerably increase the ionic conductance of NanC. The effect of Neu5Ac on the unitary current through NanC saturates at higher Neu5Ac concentrations. Interestingly, Neu5Ac reduces the ionic conductance of OmpF: frequent, long closures are seen. Therefore, in E.coli sialic acid translocation is specifically facilitated by NanC, and not by the general porin OmpF.
Advisors/Committee Members: Magin, Richard L. (advisor), Eisenberg, Robert S. (committee member), Dai, Yang (committee member), Solaro, R. John (committee member), Fill, Michael (committee member).
Subjects/Keywords: ion channels; selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Giri, J. (2012). Study of Selectivity and Permeation in Voltage-Gated Ion Channels. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/8181
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Giri, Janhavi. “Study of Selectivity and Permeation in Voltage-Gated Ion Channels.” 2012. Thesis, University of Illinois – Chicago. Accessed February 27, 2021.
http://hdl.handle.net/10027/8181.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Giri, Janhavi. “Study of Selectivity and Permeation in Voltage-Gated Ion Channels.” 2012. Web. 27 Feb 2021.
Vancouver:
Giri J. Study of Selectivity and Permeation in Voltage-Gated Ion Channels. [Internet] [Thesis]. University of Illinois – Chicago; 2012. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10027/8181.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Giri J. Study of Selectivity and Permeation in Voltage-Gated Ion Channels. [Thesis]. University of Illinois – Chicago; 2012. Available from: http://hdl.handle.net/10027/8181
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
2.
Batista, Mariana Silveira [UNESP].
Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist.
Degree: 2016, Universidade Estadual Paulista
URL: http://hdl.handle.net/11449/144421
► A planta daninha está entre as espécies de maior importância nos campos de diversas culturas. Por se tratar de uma espécie que apresenta alto poder…
(more)
▼ A planta daninha está entre as espécies de maior importância nos campos de diversas culturas. Por se tratar de uma espécie que apresenta alto poder de produzir milhares de sementes que tem se adaptado ao uso de herbicidas, seu estudo se torna de grande importância para amenizar os danos causados às culturas. O trabalho foi desenvolvido com o objetivo de estudar as características morfofisiológicas da espécie Conyza canadensis (L.) Cronquist quanto à resistência ao herbicida do grupo químico das glicinas substituídas em plantas com histórico de resistência. O experimento foi instalado e conduzido durante o segundo semestre de 2014 em condição de campo na área da Universidade Federal do Mato Grosso do Sul – Campus Chapadão do Sul. O delineamento experimental foi blocos casualizados, com 4 repetições, os tratamentos em esquema fatorial 5x5, totalizando 25 tratamentos. O fator A correspondeu ao estádio de desenvolvimento: Tamanho I – plantas com 5 cm de altura; Tamanho II - 10 cm de altura; Tamanho III – 15 cm de altura; Tamanho IV – 20 cm de altura; Tamanho V – 25 cm de altura. O fator B foram as doses do glyphosate: Dose I (sem aplicação) - Testemunha; Dose II (1200 g i.a ha-1); Dose III (2400 g i.a ha-1); Dose IV (3600 g i.a ha-1) e Dose V (4800 g i.a ha-1). Foram realizadas análises de crescimento das plantas: altura de plantas e diâmetro do caule, aos 0, 14 e 28 dias após a aplicação dos tratamentos e uma avaliação de altura de plantas remanescentes ou rebrota realizada aos 100 dias após a aplicação. Para a análise de perdas de transpiração de folhas destacadas e hidratadas as plantas estavam em fase vegetativa e coletadas no terço-médio das plantas aos 0, 4 e 8 DAA. Os dados foram submetidos à análise de variância e as medias dos tratamentos comparadas pelo Teste de Scott Knott a 5% de probabilidade. Concluiu-se que tanto o tamanho das plantas como as doses do glyphosate influenciaram na altura de plantas, no diâmetro da haste e nas perdas de transpiração da espécie Conyza canadensis (L.) Cronquist. A porcentagem de redução da altura das plantas de tamanho menor foi maior conforme as doses de glyphosate aumentaram em todos os períodos das avaliações. Plantas de tamanho menor transpiram mais do que plantas de tamanho maior sem a aplicação de herbicida. Para as perdas de transpiração, as plantas de menor tamanho que receberam a aplicação do glyphosate em doses maiores, transpiraram menos. As plantas de tamanhos maiores transpiraram mais quando submetidas a doses medianas do glyphosate quando comparadas as doses maiores.
The weed is among the species of greatest importance in the fields of different cultures. Because it is a species that has a high power to produce thousands of seeds that have adapted to the use of herbicides, their study becomes very important to mitigate the damage to crops. The work was to study the morphological and physiological characteristics of species Conyza canadensis (L.) Cronquist for resistance to the herbicide chemical group of glycines substituted in plants with a history of…
Advisors/Committee Members: Carvalho, Fernando Tadeu de [UNESP], Universidade Estadual Paulista (UNESP).
Subjects/Keywords: Buva; Seletividade; Glyphosate; Horseweed; Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Batista, M. S. [. (2016). Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist. (Thesis). Universidade Estadual Paulista. Retrieved from http://hdl.handle.net/11449/144421
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Batista, Mariana Silveira [UNESP]. “Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist.” 2016. Thesis, Universidade Estadual Paulista. Accessed February 27, 2021.
http://hdl.handle.net/11449/144421.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Batista, Mariana Silveira [UNESP]. “Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist.” 2016. Web. 27 Feb 2021.
Vancouver:
Batista MS[. Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist. [Internet] [Thesis]. Universidade Estadual Paulista; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11449/144421.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Batista MS[. Diferenças no metabolismo das plantas que determinam resistência ao glyphosate em Conyza canadensis (L.) Cronquist. [Thesis]. Universidade Estadual Paulista; 2016. Available from: http://hdl.handle.net/11449/144421
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Penn State University
3.
Ren, Siyuan.
The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg.
Degree: 2013, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/19053
► College ranking attracts attention of worldwide intellectuals. Much previous work has been done by scholars to utter the importance of college rankings as they will…
(more)
▼ College ranking attracts attention of worldwide intellectuals. Much previous work has been done by scholars to utter the importance of college rankings as they will affect student choice and institutional behavior. Previous research has shown that a causal link between rankings and subsequent admission factors does exist (Bowman & Bastedo, 2009). Ranking now is considered to be an indicator of academic prestige and a predictor of application, admission and enrollment. The US News & World Report College Rankings is one of the most influential ranking systems in United States; it gives information to students, families, alumni, staff and faculty. This paper, motivated by Monks and Ehrenberg (1999), attempts to use multivariate regression model, as well as a new and larger data set, to investigate how rank changes affect institutional admission behaviors over the first decade of 2000s.
In this study, I find that institutional
selectivity is impaired while institutions receive unfavorable ranking. With ranking number increasing by 1, the admission rate of current year will increase by 0.1 percentage point, the enrollment rate of current year will decrease by 0.2 percentage point, the 25th percentile freshmen SAT score of current year will decrease by 0.871 points, and the 75th percentile freshmen SAT score of current year will decrease by 0.706 points. Results also suggest that tuitions are independent of ranking changes, and are increasing steadily over year. There is no significant statistical difference between top 25 institutions and non-top25 institutions.
Advisors/Committee Members: Soo Yong Byun, Thesis Advisor/Co-Advisor, Liang Zhang, Thesis Advisor/Co-Advisor, Mindy L Kornhaber, Thesis Advisor/Co-Advisor.
Subjects/Keywords: college ranking; selectivity; prestige
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ren, S. (2013). The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/19053
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ren, Siyuan. “The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg.” 2013. Thesis, Penn State University. Accessed February 27, 2021.
https://submit-etda.libraries.psu.edu/catalog/19053.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ren, Siyuan. “The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg.” 2013. Web. 27 Feb 2021.
Vancouver:
Ren S. The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Feb 27].
Available from: https://submit-etda.libraries.psu.edu/catalog/19053.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ren S. The Impact of U.s. News & World Report Colleges Rankings:
an Update to Monks and Ehrenberg. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/19053
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Penn State University
4.
Noh, Young Dong.
Cation exchange properties of highly charged swelling micas and titanosilicates
.
Degree: 2011, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/11659
► The principal goal of this thesis work was to investigate cation exchange properties of highly charged swelling micas such as Na1Si3AlMg3O10F2 • xH2O (Na-2-mica), Na1.5Si2.5Al1.5Mg3O10F2…
(more)
▼ The principal goal of this thesis work was to investigate cation exchange properties of highly charged swelling micas such as Na1Si3AlMg3O10F2 • xH2O (Na-2-mica), Na1.5Si2.5Al1.5Mg3O10F2 • xH2O (Na-3-mica), and Na2Si2Al2Mg3O10F2 • xH2O (Na-4-mica) and titanosilicates such as sodium Engelhard titanosilicate 4 (Na-ETS-4) and Na-titanosilicate. The three mica ion exchangers were synthesized using a NaCl melt method and the two Na titanosilicates were synthesized by hydrothermal treatment, and characterized by X-ray diffraction and scanning electron microscopy. In addition, 29Si and 27Al MASNMR spectroscopy was used to understand layer charge properties of Na-micas and local chemical binding environment of Si and Al.
Cation exchange isotherms and Kielland plots of the above five ion exchangers were constructed in order to evaluate their selective cation exchange properties for Sr2+ and Ba2+ and heavy metals such as Hg2+ and Co2+. 2Na+→ Sr2+ exchange isotherms and Kielland plots revealed that Na-2-mica, Na-ETS-4, and Na-titanosilicate showed high
selectivity for Sr2+. For the case of 2Na+→ Ba2+ exchange, Na-2-mica and Na-ETS-4 had high preference for Ba2+ over Na+ with most of the equilibrium solutions used. Na-2-mica showed higher
selectivity for Sr2+ and Ba2+ than Na-3-mica and Na-4-mica because of higher expansibility of Na-2-mica resulting in easier accessibility to exchange sites in interlayer space than the other two micas. This expansibility was limited by increasing electrostatic attraction with the increase in intercalated divalent cations. In the case of 2Na+ → Hg2+ exchange reaction, Na-ETS-4 was found to have higher distribution coefficient (Kd) value than any other ion exchangers tested. The Kielland plot for Hg2+ showed that only Na-ETS-4 had
selectivity for mercury (II) with most of the exchange solutions used. 2Na+ → Co2+exchange equilibria revealed that Na-2-mica and Na-ETS-4 had high
selectivity for cobalt ions over sodium ions at low Co equivalent fraction in the solid phase.
Two different (001) phases of ~12 Å and ~14 Å were seen in the XRD patterns of the Na-micas after 2Na+ → M2+ (M=Sr, Ba, Hg) exchange reactions with different exchange solutions. This difference in the d001-value suggested the presence of adsorbed divalent cations with different hydration states in interlayer space after ion exchange reactions, because of partial dehydration of intercalated cations by strong electrostatic attraction between adsorbed cations and negatively charged layers. Both the extent of divalent cations intercalated and layer charge density affected the attractive electrostatic force. As the uptake of adsorbed divalent cations in the solid phase and the layer charge density increased, the electrostatic attraction increased contributing to the increase in the extent of the dehydration of cations intercalated. Unlike other cases, after 2Na+ → Co2+ exchange reaction, strong ~14 Å phase of Na-2-mica was retained even at high Co2+ uptake, while ~12 Å phase decreased as the amount…
Advisors/Committee Members: Sridhar Komarneni, Dissertation Advisor/Co-Advisor, Sridhar Komarneni, Committee Chair/Co-Chair, Maryann Victoria Bruns, Committee Member, Carmen Enid Martinez, Committee Member, Della M Roy, Committee Member.
Subjects/Keywords: Mica; Titanosilicate; Ion exchange; Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Noh, Y. D. (2011). Cation exchange properties of highly charged swelling micas and titanosilicates
. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/11659
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Noh, Young Dong. “Cation exchange properties of highly charged swelling micas and titanosilicates
.” 2011. Thesis, Penn State University. Accessed February 27, 2021.
https://submit-etda.libraries.psu.edu/catalog/11659.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Noh, Young Dong. “Cation exchange properties of highly charged swelling micas and titanosilicates
.” 2011. Web. 27 Feb 2021.
Vancouver:
Noh YD. Cation exchange properties of highly charged swelling micas and titanosilicates
. [Internet] [Thesis]. Penn State University; 2011. [cited 2021 Feb 27].
Available from: https://submit-etda.libraries.psu.edu/catalog/11659.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Noh YD. Cation exchange properties of highly charged swelling micas and titanosilicates
. [Thesis]. Penn State University; 2011. Available from: https://submit-etda.libraries.psu.edu/catalog/11659
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Boston College
5.
Liu, Nanjun.
Chemical Approaches to Understand the On-Membrane Action of
Magainin 2.
Degree: MS, Chemistry, 2011, Boston College
URL: http://dlib.bc.edu/islandora/object/bc-ir:101619
► There is substantial interest in exploring antibiotic alternatives with a new mode of action due to the increasing rates of bacterial resistance against current antibiotics.…
(more)
▼ There is substantial interest in exploring antibiotic
alternatives with a new mode of action due to the increasing rates
of bacterial resistance against current antibiotics. Antimicrobial
peptides (AMPs) may take up the battle against bacteria in the
future because as a result of their membrane-lysis mechanism, it is
more difficult for bacteria to develop resistance against AMPs.
Although AMPs could preferentially bind to and disrupt negatively
charged bacterial membranes through electrostatic and hydrophobic
interactions, there is still a great need to further increase the
potency and selective toxicity towards bacteria for clinical
applications. Herein, we present two strategies to improve the
selectivity: light activation and environment-responsive moiety
incorporation. Along the way, we also explored the effect of
structure stabilization on AMPs action. A well-characterized
antimicrobial peptide magainin 2 (mag2) was used as a prototype.
Chemical manipulations of mag2 sequence were achieved by
incorporation of unnatural amino acids. The
selectivity was then
tested on liposomes as a membrane model, as well as on bacterial
cells and human red blood cells (hRBCs). Different extents of
selectivity enhancement were observed from the modified peptides,
and within the attempts to illustrate these results, we have gained
useful information revealing the membrane-lysis mechanism, which
may help us to rationally design and engineer AMPs as therapeutic
drugs in the future.
Advisors/Committee Members: Mary F. Roberts (Thesis advisor).
Subjects/Keywords: Antibiotics; Antimicrobial peptides; Mechanism; Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, N. (2011). Chemical Approaches to Understand the On-Membrane Action of
Magainin 2. (Masters Thesis). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101619
Chicago Manual of Style (16th Edition):
Liu, Nanjun. “Chemical Approaches to Understand the On-Membrane Action of
Magainin 2.” 2011. Masters Thesis, Boston College. Accessed February 27, 2021.
http://dlib.bc.edu/islandora/object/bc-ir:101619.
MLA Handbook (7th Edition):
Liu, Nanjun. “Chemical Approaches to Understand the On-Membrane Action of
Magainin 2.” 2011. Web. 27 Feb 2021.
Vancouver:
Liu N. Chemical Approaches to Understand the On-Membrane Action of
Magainin 2. [Internet] [Masters thesis]. Boston College; 2011. [cited 2021 Feb 27].
Available from: http://dlib.bc.edu/islandora/object/bc-ir:101619.
Council of Science Editors:
Liu N. Chemical Approaches to Understand the On-Membrane Action of
Magainin 2. [Masters Thesis]. Boston College; 2011. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101619
Université Catholique de Louvain
6.
Meyer, Nathalie.
Noble metal supported catalysts for lactose transformations in liquid phase.
Degree: 2014, Université Catholique de Louvain
URL: http://hdl.handle.net/2078.1/151944
► Carbohydrates are an important source of renewable materials which can be converted into high added-value products. Sugar transformations should ideally be carried out with recyclable…
(more)
▼ Carbohydrates are an important source of renewable materials which can be converted into high added-value products. Sugar transformations should ideally be carried out with recyclable catalysts, in water, with the highest possible selectivity in the desired product. The aim of the present work was to explore the microstructural properties of the heterogeneous catalysts needed to carry out selectively lactose oxidation into lactobionic acid and lactose hydrogenation into lactitol. The first part consisted in the investigation of the influence of two functionalized supports (γ-Al2O3 and Cxerogel) modified by metallic precursor grafting and activation on the catalytic performances in lactose oxidation. The oxygenated functions were shown to be detrimental. This was confirmed by the results obtained with an inert support, boron nitride, which can be a promising alternative support, ensuring high selectivity. Subsequently, the optimal range of particle size within Pd/h-BN catalysts for high activity and selectivity was investigated and the optimal size was determined between 3 and 15 nm with no particles inferior to 3 nm. The effectiveness of Au/h-BN was also evaluated and it exhibited spectacular performances. Au/h-BN was shown to be a good candidate for thermal regeneration for recycling. Lactose hydrogenation was finally investigated with Pd/h-BN and particles inferior to 3 nm were also undesired. The selectivity obtained in lactose hydrogenation seems to be greatly dependent on the mechanism of each possible side reaction.
(SC - Sciences) – UCL, 2014
Advisors/Committee Members: UCL - SST/IMCN/MOST - Molecules, Solids and Reactivity, UCL - Faculté des Sciences, Peeters, Daniel, Gaigneaux, Eric, Prati, Laura, Marchand, Jacqueline, Pirard, Jean-Paul, Hermans, Sophie, Devillers, Michel.
Subjects/Keywords: Lactose; Boron nitride; Palladium; Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Meyer, N. (2014). Noble metal supported catalysts for lactose transformations in liquid phase. (Thesis). Université Catholique de Louvain. Retrieved from http://hdl.handle.net/2078.1/151944
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Meyer, Nathalie. “Noble metal supported catalysts for lactose transformations in liquid phase.” 2014. Thesis, Université Catholique de Louvain. Accessed February 27, 2021.
http://hdl.handle.net/2078.1/151944.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Meyer, Nathalie. “Noble metal supported catalysts for lactose transformations in liquid phase.” 2014. Web. 27 Feb 2021.
Vancouver:
Meyer N. Noble metal supported catalysts for lactose transformations in liquid phase. [Internet] [Thesis]. Université Catholique de Louvain; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/2078.1/151944.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Meyer N. Noble metal supported catalysts for lactose transformations in liquid phase. [Thesis]. Université Catholique de Louvain; 2014. Available from: http://hdl.handle.net/2078.1/151944
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
KTH
7.
Saur, Ann-Kathrin.
Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions.
Degree: Chemical Science and Engineering (CHE), 2011, KTH
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49788
► The aim of the project was to synthesize α1,2-linked and α1,6-linked dimannosides linked through either an oxygen-atom or a sulphur-atom, and subsequently test the…
(more)
▼ The aim of the project was to synthesize α1,2-linked and α1,6-linked dimannosides linked through either an oxygen-atom or a sulphur-atom, and subsequently test the binding properties of the dimannosides to lectins with known specificity towards mannose-containing glycans. Thedimannosides were prepared by a glycosylation reaction using selectively protected monosaccharides containing a thiol or alcohol nucleophilic glycosyl acceptor and a series of different glycosyl donors. The synthetic routes to the different building blocks were designed to efficiently make use of common intermediate compounds to streamline the synthesis. The glycosyl acceptors used forthe synthesis of α1,2-linked as well as α1,6-linked dimannosides were synthesized in few steps and diversified only in the last steps of the synthesis. The glycosyl donors used in the study were synthesized from commercially available starting material in a straightforward and convenientsynthesis in 7 to 8 steps.
Subjects/Keywords: Synthesis; Carbohydrate; Selectivity; Protein; Analysis
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Saur, A. (2011). Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49788
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Saur, Ann-Kathrin. “Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions.” 2011. Thesis, KTH. Accessed February 27, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49788.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Saur, Ann-Kathrin. “Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions.” 2011. Web. 27 Feb 2021.
Vancouver:
Saur A. Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions. [Internet] [Thesis]. KTH; 2011. [cited 2021 Feb 27].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49788.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Saur A. Synthesis of α1,2- and α1,6, linked Dimannosides for Analysis of Protein Carbohydrate Interactions. [Thesis]. KTH; 2011. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49788
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Montana State University
8.
Winward, Shelly Janine.
Attentional control and asymmetric priming.
Degree: MS, College of Letters & Science, 2012, Montana State University
URL: https://scholarworks.montana.edu/xmlui/handle/1/2563
► The current research examined the relation between attentional control and strategies used during a lexical decision task. Participants completed a battery of three attentional control…
(more)
▼ The current research examined the relation between attentional control and strategies used during a lexical decision task. Participants completed a battery of three attentional control tasks and also performed a lexical decision task with symmetrical (e.g., brother, sister) or asymmetrical associated items presented in either the forward (e.g., stork, baby) or backward direction (e.g., baby, stork). Results indicated that individuals higher in attentional control showed greater priming for forward associates, but no priming difference in attentional control for backward associates. Further, equal priming occurred for symmetrical associates regardless of attentional control. Results thus illustrated that both high and low attentional control participants used a retrospective semantic matching strategy, while participants high in attentional control used an expectancy generation strategy. Implications are discussed in terms of existing strategies of attentional control and semantic priming.
Advisors/Committee Members: Chairperson, Graduate Committee: Keith A. Hutchison (advisor).
Subjects/Keywords: Attention.; Selectivity (Psychology).; Priming (Psychology).
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Winward, S. J. (2012). Attentional control and asymmetric priming. (Masters Thesis). Montana State University. Retrieved from https://scholarworks.montana.edu/xmlui/handle/1/2563
Chicago Manual of Style (16th Edition):
Winward, Shelly Janine. “Attentional control and asymmetric priming.” 2012. Masters Thesis, Montana State University. Accessed February 27, 2021.
https://scholarworks.montana.edu/xmlui/handle/1/2563.
MLA Handbook (7th Edition):
Winward, Shelly Janine. “Attentional control and asymmetric priming.” 2012. Web. 27 Feb 2021.
Vancouver:
Winward SJ. Attentional control and asymmetric priming. [Internet] [Masters thesis]. Montana State University; 2012. [cited 2021 Feb 27].
Available from: https://scholarworks.montana.edu/xmlui/handle/1/2563.
Council of Science Editors:
Winward SJ. Attentional control and asymmetric priming. [Masters Thesis]. Montana State University; 2012. Available from: https://scholarworks.montana.edu/xmlui/handle/1/2563
University of New Mexico
9.
Peña-Esparza, Yajaira.
Attentional biases in dysphoric college students.
Degree: Psychology, 2011, University of New Mexico
URL: http://hdl.handle.net/1928/13106
► Cognitive biases in attention to emotional stimuli in an ethnically diverse sample of dysphoric and non-dysphoric college students were explored. The present study advanced the…
(more)
▼ Cognitive biases in attention to emotional stimuli in an ethnically diverse sample of dysphoric and non-dysphoric college students were explored. The present study advanced the literature by using ecologically valid eye movement data to assess attention. We hypothesized that dysphoric participants would orient their attention toward sad faces more quickly than the students without dysphoria. We also hypothesized that the dysphoric participants would sustain their attention on sad faces longer than the non-dysphoric participants. Caucasian and Latino undergraduate students were categorized into dysphoric (n = 30) and non-dysphoric (n = 36 based depressive symptom endorsement on the BDI-II (non-dysphoric: BDI-II ≤ 6, dysphoric: BDI-II \u2265 14). Eye movements were recorded with an eye-tracking device while the students viewed picture pairs of faces expressing sadness, happiness, or no emotion. The task consisted of 48 face pairs presented twice for a total of 96 trials. Consistent with the literature, dysphoric participants showed a negative bias in duration when sad faces were paired with neutral faces, but not when they were paired to happy faces. Dysphoric participants were not more likely to initially orient toward sad faces and when they did, latency was not significantly shorter to the sad face than to the other faces. Furthermore, depressive symptom scores were not associated with attentional biases for the dysphoric participants. Taken together, these findings are consistent with literature suggesting dysphoria and depression are characterized by elaboration of mood-congruent stimuli at later stages of information processing. However, the context in which the negative stimuli is presented is important. The elaboration of mood congruent stimuli was only evident in the context of a paired neutral stimuli; a paired positive stimuli did not support this elaboration effect. Additionally, symptom severity on the BDI-II did not influence the elaboration bias dysphoric participants exhibited. These findings have significant implications for the treatment and prevention of depression.
Advisors/Committee Members: Verney, Steven, Verney, Steven, Smith, Bruce, Ruthruff, Eric.
Subjects/Keywords: Selectivity (Psychology); Depression; Face perception.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Peña-Esparza, Y. (2011). Attentional biases in dysphoric college students. (Masters Thesis). University of New Mexico. Retrieved from http://hdl.handle.net/1928/13106
Chicago Manual of Style (16th Edition):
Peña-Esparza, Yajaira. “Attentional biases in dysphoric college students.” 2011. Masters Thesis, University of New Mexico. Accessed February 27, 2021.
http://hdl.handle.net/1928/13106.
MLA Handbook (7th Edition):
Peña-Esparza, Yajaira. “Attentional biases in dysphoric college students.” 2011. Web. 27 Feb 2021.
Vancouver:
Peña-Esparza Y. Attentional biases in dysphoric college students. [Internet] [Masters thesis]. University of New Mexico; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1928/13106.
Council of Science Editors:
Peña-Esparza Y. Attentional biases in dysphoric college students. [Masters Thesis]. University of New Mexico; 2011. Available from: http://hdl.handle.net/1928/13106
University of Minnesota
10.
Fan, Yang.
Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity.
Degree: PhD, Chemistry, 2018, University of Minnesota
URL: http://hdl.handle.net/11299/200195
► Hydrogen bonding exhibits its importance in enzyme-catalyzed chemical transformations, naturally occurring three-dimensional architectures and molecular recognition. In recent years, synthetic chemists have successfully exploited hydrogen…
(more)
▼ Hydrogen bonding exhibits its importance in enzyme-catalyzed chemical transformations, naturally occurring three-dimensional architectures and molecular recognition. In recent years, synthetic chemists have successfully exploited hydrogen bonds and developed many enantioselective organocatalysts. As a result, small molecule hydrogen bond donors along with organometallic species and enzymes are now recognized as playing a major role in asymmetric synthesis. Thiourea derivatives are among the most common and widely-developed hydrogen bond catalysts. Impressive results in terms of both yields and enantioselectivities in asymmetric syntheses have been obtained. A key feature in their success is the ability of these compounds to simultaneously donate two hydrogen bonds to a substrate, despite their relatively weak acidity. This provides highly stereoconfined environments when chiral moieties are incorporated into the thiourea and has made them the subject of extensive research efforts. The work described in this thesis focuses on the development of a class of positively charged acidity-enhanced thiourea catalysts which make use of an alkylated pyridinium substituent and an appropriate non-coordinating counteranion to enhance their N‒H acidities and improve their catalytic activities by orders of magnitude in a variety of transformations. A series of these catalysts have been synthesized and their reactivities in both asymmetric and non-asymmetric transformations were explored. Simple and highly efficient synthetic schemes and excellent catalytic results have been discovered for these novel species.
Subjects/Keywords: catalysis; charge; reactivity; selectivity; thiourea
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fan, Y. (2018). Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/200195
Chicago Manual of Style (16th Edition):
Fan, Yang. “Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity.” 2018. Doctoral Dissertation, University of Minnesota. Accessed February 27, 2021.
http://hdl.handle.net/11299/200195.
MLA Handbook (7th Edition):
Fan, Yang. “Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity.” 2018. Web. 27 Feb 2021.
Vancouver:
Fan Y. Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity. [Internet] [Doctoral dissertation]. University of Minnesota; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11299/200195.
Council of Science Editors:
Fan Y. Electrostatically Enhanced Thioureas: Synthesis, Reactivity and Selectivity. [Doctoral Dissertation]. University of Minnesota; 2018. Available from: http://hdl.handle.net/11299/200195
University of Minnesota
11.
Bigert, Matthew.
Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable.
Degree: MS, Chemistry, 2018, University of Minnesota
URL: http://hdl.handle.net/11299/201018
► Clearly, in typical separations in HPLC, selectivity is the most important variable for improving resolution and the optimization of selectivity is the primary focus of…
(more)
▼ Clearly, in typical separations in HPLC, selectivity is the most important variable for improving resolution and the optimization of selectivity is the primary focus of most method development effort in reversed-phase liquid chromatography (RPLC). We have developed a family of novel techniques in which two columns with markedly different chromatographic selectivities are combined in tandem. One then uses another chromatographic variable (e.g. temperature, flow rate, eluent composition) which has different values for the two columns to continuously “tune” the selectivity. We call this family of techniques XT2C, meaning that the variable X (temperature, etc.) is used to continuously tune the combined selectivity of the tandem columns. By serially coupling the columns, our approach eliminates the common “selectivity discontinuity” problem encountered by analysts when the type of column used is changed. Previously, we utilized the thermally tuned tandem column (T3C) concept in which selectivity was adjusted by independently tuning the two column temperatures. The primary difference between the experimental setup for T3C and XT2C is that a second pump and static micro-mixer are placed between the two columns. In this study, we describe the eluent tuned tandem column concept in which selectivity is continuously tuned by independently controlling the eluent composition of each column. When the percent organic modifier in the eluent (%B) is adjusted, the concept is denoted “solvent tuned tandem column (ST2C)”. Likewise, when the ionic strength (buffer concentration) is tuned, the concept is referred to as ionic strength tuned tandem column (IT2C). The objective of the present study is to evaluate the applicability of IT2C and ST2C to mixtures of ionic and non-ionic analytes, respectively. We also describe the use of a simple computer assisted optimization strategy based on the window diagram method. This strategy allows for XT2C optimization based on only four to six initial data acquisition runs. ST2C and IT2C are comparable in terms of chromatographic performance to T3C and provide flexibility in optimizing selectivity but do not require thermally stable columns.
Subjects/Keywords: Eluent; HPLC; Selectivity; Tandem
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bigert, M. (2018). Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable. (Masters Thesis). University of Minnesota. Retrieved from http://hdl.handle.net/11299/201018
Chicago Manual of Style (16th Edition):
Bigert, Matthew. “Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable.” 2018. Masters Thesis, University of Minnesota. Accessed February 27, 2021.
http://hdl.handle.net/11299/201018.
MLA Handbook (7th Edition):
Bigert, Matthew. “Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable.” 2018. Web. 27 Feb 2021.
Vancouver:
Bigert M. Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable. [Internet] [Masters thesis]. University of Minnesota; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11299/201018.
Council of Science Editors:
Bigert M. Selectivity Optimization in Tandem Column Liquid Chromatography Using the Eluent Composition as the Tuning Variable. [Masters Thesis]. University of Minnesota; 2018. Available from: http://hdl.handle.net/11299/201018
Southern Illinois University
12.
Parks, Sherrie L.
The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan.
Degree: MA, Psychology, 2013, Southern Illinois University
URL: https://opensiuc.lib.siu.edu/theses/1143
► TITLE: THE SOUND OF MUSIC: THE INFLUENCE OF EVOKED EMOTION ON RECOGNITION MEMORY FOR MUSICAL EXCERPTS ACROSS THE LIFESPAN Socioemotional Selectivity Theory (Carstensen, 1999)…
(more)
▼ TITLE: THE SOUND OF MUSIC: THE INFLUENCE OF EVOKED EMOTION ON RECOGNITION MEMORY FOR MUSICAL EXCERPTS ACROSS THE LIFESPAN Socioemotional
Selectivity Theory (Carstensen, 1999) posits that as people age, they selectively focus on positive aspects of emotional stimuli as opposed to negative as a way of regulating emotions. Thus, older adults remember positive information better than negative. This hypothesis has been tested extensively with visual stimuli, but rarely with auditory stimuli. Findings from this study provide support in the auditory domain. In this study, 135 younger, middle-aged, and older adults heard consonant (pleasant) and dissonant (unpleasant) musical excerpts. Participants were randomly assigned to either a Study Only condition, in which they heard excerpts and studied them for later recognition, a Rate Only condition, in which they rated the excerpts and were tested later in a surprise recognition test, or a Rate and Study condition, in which they rated and studied the excerpts for later recognition. Results indicated that younger, middle-aged and older adults remembered consonant (pleasant) musical excerpts better than dissonant (unpleasant) musical excerpts overall and provide support for the hypotheses of the Socioemotional
Selectivity Theory.
Advisors/Committee Members: Clancy Dollinger, Stephanie.
Subjects/Keywords: music; Socioemotional Selectivity Theory
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Parks, S. L. (2013). The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan. (Masters Thesis). Southern Illinois University. Retrieved from https://opensiuc.lib.siu.edu/theses/1143
Chicago Manual of Style (16th Edition):
Parks, Sherrie L. “The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan.” 2013. Masters Thesis, Southern Illinois University. Accessed February 27, 2021.
https://opensiuc.lib.siu.edu/theses/1143.
MLA Handbook (7th Edition):
Parks, Sherrie L. “The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan.” 2013. Web. 27 Feb 2021.
Vancouver:
Parks SL. The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan. [Internet] [Masters thesis]. Southern Illinois University; 2013. [cited 2021 Feb 27].
Available from: https://opensiuc.lib.siu.edu/theses/1143.
Council of Science Editors:
Parks SL. The sound of music: The influence of evoked emotion on recognition memory for musical excerpts across the lifespan. [Masters Thesis]. Southern Illinois University; 2013. Available from: https://opensiuc.lib.siu.edu/theses/1143
13.
Putnam, Philip.
Neural Substrates of Social Behavior in the Primate Brain
.
Degree: 2019, University of Arizona
URL: http://hdl.handle.net/10150/631936
► Many brain structures are known for carrying out more than one function. Among these structures the amygdala emerged particularly versatile, as it has been implicated…
(more)
▼ Many brain structures are known for carrying out more than one function. Among these structures the amygdala emerged particularly versatile, as it has been implicated in cognitive processes that range from sensory-perceptual, to decision-making, and to overt behaviors accompanied by autonomic responses. While no single functional definition can capture its role in the brain, the diversity of functions linked to the amygdala is likely reflected in the response properties of its component neurons. The goal of this study was to determine the extent to which single neurons in the amygdala can exhibit multiple types of stimulus-
selectivity and/or task-related responses in the context of a complex task. The task involved learning and decision making based on stimulus-reward associations where the choices were presented as multiple simultaneously playing videos with social and non-social content. Here we report that amygdala neurons are tuned to multiple stimulus and task dimensions. Furthermore a disproportionate number of neurons responded to all of the features examined. This demonstration of multi-dimensional
selectivity in the amygdala provides evidence that the amygdala is not composed exclusively of discrete circuits, but rather of common overlapping populations that encode multiple types of information.
Advisors/Committee Members: Cowen, Stephen (advisor), Gothard, Katalin (committeemember), Bao, Shaowen (committeemember), Cai, Haijiang (committeemember).
Subjects/Keywords: amygdala;
Multi-dimensional selectivity;
rhesus
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Putnam, P. (2019). Neural Substrates of Social Behavior in the Primate Brain
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/631936
Chicago Manual of Style (16th Edition):
Putnam, Philip. “Neural Substrates of Social Behavior in the Primate Brain
.” 2019. Doctoral Dissertation, University of Arizona. Accessed February 27, 2021.
http://hdl.handle.net/10150/631936.
MLA Handbook (7th Edition):
Putnam, Philip. “Neural Substrates of Social Behavior in the Primate Brain
.” 2019. Web. 27 Feb 2021.
Vancouver:
Putnam P. Neural Substrates of Social Behavior in the Primate Brain
. [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10150/631936.
Council of Science Editors:
Putnam P. Neural Substrates of Social Behavior in the Primate Brain
. [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/631936
University of Georgia
14.
Zaffos, Andrew Alexander.
Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/26836
► This study tests the relationship between fossil abundance and extinction. Samples were collected from the Late Ordovician type-Cincinnatian Series and the earliest Silurian Brassfield Formation…
(more)
▼ This study tests the relationship between fossil abundance and extinction. Samples were collected from the Late Ordovician type-Cincinnatian Series and the earliest Silurian Brassfield Formation of the Cincinnati Arch. The abundance of
brachiopod genera and families was assessed with nine different metrics to account for differences across spatial and temporal scale. Each of these metrics was compared to global duration in the fossil record and survivorship across the
Ordovician/Silurian boundary. The results indicate that survivors were more abundant than victims, and are further evidence that the Ordovician/Silurian extinction was not accompanied by a macroevolutionary selectivity regime shift. Furthermore,
abundances during this interval are not correlated with duration in the fossil record, a finding that is interpreted as further evidence of changing selectivity patterns through time.
Subjects/Keywords: Mass extinction; Selectivity; Brachiopods
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zaffos, A. A. (2014). Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/26836
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zaffos, Andrew Alexander. “Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA.” 2014. Thesis, University of Georgia. Accessed February 27, 2021.
http://hdl.handle.net/10724/26836.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zaffos, Andrew Alexander. “Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA.” 2014. Web. 27 Feb 2021.
Vancouver:
Zaffos AA. Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10724/26836.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zaffos AA. Abundance and extinction at the Ordovician/Silurian boundary of the Cincinnati Arch, USA. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/26836
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Michigan State University
15.
Conn, Katelyn M.
Selection history : a third source of bias in attentional control?.
Degree: 2019, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:47765
► Thesis Ph. D. Michigan State University. Psychology 2019
"Researchers have long posited that attention is controlled through two modes: a bottom-up mode in which attention…
(more)
▼ Thesis Ph. D. Michigan State University. Psychology 2019
"Researchers have long posited that attention is controlled through two modes: a bottom-up mode in which attention is directed automatically to items based on their physical salience and a top-down mode in which the observer exerts volitional influence to prioritize information relevant to current task goals. Recently, however, others have begun to question the validity of this model and suggest that attention is also driven by prior experience. The current work investigates how this third mechanism, called selection history, is implemented in visual search. We conducted a series of experiments to investigate the conditions under which observers could learn to prioritize a frequently selected feature. Participants searched for a target horizontal or vertical line, which appeared in one of two possible colors, among diagonal distractors and made a judgement about the target (i.e. length or orientation). Each experiment began with a training phase, during which targets were presented more frequently in one of the two possible colors (called the "high probability color"), followed by a test phase in which targets appeared equally often in both colors. We predicted that participants would continue to respond more quickly to targets presented in the high probability color in the test phase, and that this learning would occur implicitly and thus be distinguishable from top-down control. In addition to this question, Experiments 1 and 2 examined whether color must be bound to other defining features of a stimulus (i.e. the lines must appear in colored font) for participants to implicitly develop a lingering bias toward the high probability color in the line length judgement task. The results of these experiments indicated that participants implicitly learned to prioritize the high probability color regardless of whether color was inherently bound to the stimulus. The remaining experiments tested whether implicit learning that leads to a lingering bias attributable to selection history occurs automatically when specific features are encountered more frequently and are diagnostic of outcomes. Specifically, we predicted that implicit learning would be modulated by the amount of attention devoted to the task and whether perceptual load permitted the passive processing of irrelevant but predictive color. Experiments 3 and 4 tested this prediction by manipulating the selection difficulty (the ease of distinguishing a target from distractors). In both tasks, participants prioritized the high probability color overall, but this effect was driven by participants who explicitly recognized the high probability color. Finally, Experiment 5 manipulated the perceptual difficulty of distinguishing the stimuli from the background by comparing the performance of participants who viewed the stimuli in a high contrast white font (Experiment 5a) to those who viewed the stimuli in a low contrast dark gray font against the black background (Experiment 5b). Although the participants in…
Advisors/Committee Members: Ravizza, Susan M, Liu, Taosheng, Becker, Mark, Johnson, Alexander.
Subjects/Keywords: Attention; Selectivity (Psychology); Cognitive psychology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Conn, K. M. (2019). Selection history : a third source of bias in attentional control?. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:47765
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Conn, Katelyn M. “Selection history : a third source of bias in attentional control?.” 2019. Thesis, Michigan State University. Accessed February 27, 2021.
http://etd.lib.msu.edu/islandora/object/etd:47765.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Conn, Katelyn M. “Selection history : a third source of bias in attentional control?.” 2019. Web. 27 Feb 2021.
Vancouver:
Conn KM. Selection history : a third source of bias in attentional control?. [Internet] [Thesis]. Michigan State University; 2019. [cited 2021 Feb 27].
Available from: http://etd.lib.msu.edu/islandora/object/etd:47765.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Conn KM. Selection history : a third source of bias in attentional control?. [Thesis]. Michigan State University; 2019. Available from: http://etd.lib.msu.edu/islandora/object/etd:47765
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
16.
Khakpay, Amir.
Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes.
Degree: M.S. in Engineering Science, Chemical Engineering, 2016, University of Mississippi
URL: https://egrove.olemiss.edu/etd/399
► This experimental study explore the reverse-selective potential of RTIL based membranes by lowering the solubility of the non-condensing gases like N2 and CH4. It explored…
(more)
▼ This experimental study explore the reverse-selective potential of RTIL based membranes by lowering the solubility of the non-condensing gases like N2 and CH4. It explored reverse-
selectivity by measuring the permeance of carbon dioxide, nitrogen, methane, propylene, propane, 1-butene, and butane in supported ionic liquid membranes (SILM). Particular attention was given to the reverse-selective behavior in the propane/methane and propane/nitrogen separations. For this purpose, a series of experiments were conducted in a batch gas permeance system. The permeance of the above-mentioned gases was obtained using polyvinylidene fluoride (PVDF) as the support and [emim][Tf2N], [emim][BF4], [emim][TfO], [emim][DCA], [emim][SCN], and [bmim][NO3] as immobilized room temperature ionic liquid (RTIL). The results showed that permeance of carbon dioxide was the highest in [emim][Tf2N], while it was the lowest in [bmim][NO3]. Moreover, permeance of the tested gases increased in the following order of anions: [Tf2N] > [TfO] > [BF4] > [SCN] > [DCA] > [NO 3]. In addition, the molar volume of the tested RTIL has a positive effect on the permeance of the tested gases. However, for the viscosity less than 30 cP, an increase in the viscosity of the tested RTILs leads to an increase in the permeance. In contrast, for the viscosity larger than 30 cP, the permeance decreases with an escaltion in the viscosity. Furthermore, the permeance of CH4 and N2 was investigated in terms of hydrogen bond accepting ability of the RTIL, as an indication of the gas/ionic liquid solution nonideality. The results showed that an increase in the nonideality of the solution leads to a decrease in the permeance of CH4 and N 2, which is in agreement with results reported by Carvalho for CH 4 [1].
Advisors/Committee Members: Paul Scovazzo, Sasan Nouranian, Adam E. Smith.
Subjects/Keywords: Permeance; Reverse-Selectivity; Rtil; Selectivity; Silm; Solubility; Chemical Engineering
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Khakpay, A. (2016). Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes. (Thesis). University of Mississippi. Retrieved from https://egrove.olemiss.edu/etd/399
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Khakpay, Amir. “Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes.” 2016. Thesis, University of Mississippi. Accessed February 27, 2021.
https://egrove.olemiss.edu/etd/399.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Khakpay, Amir. “Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes.” 2016. Web. 27 Feb 2021.
Vancouver:
Khakpay A. Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes. [Internet] [Thesis]. University of Mississippi; 2016. [cited 2021 Feb 27].
Available from: https://egrove.olemiss.edu/etd/399.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Khakpay A. Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes. [Thesis]. University of Mississippi; 2016. Available from: https://egrove.olemiss.edu/etd/399
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
King Abdullah University of Science and Technology
17.
Al Jabri, Nouf M.
Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions.
Degree: Physical Science and Engineering (PSE) Division, 2017, King Abdullah University of Science and Technology
URL: http://hdl.handle.net/10754/625826
► Polystyrene (PS) is one of the most important polymers in the plastic sector due to its inexpensive cost as well as many preferred properties. Its…
(more)
▼ Polystyrene (PS) is one of the most important polymers in the plastic sector due to its
inexpensive cost as well as many preferred properties. Its international market is
expected to achieve $28.2 billion by 2019. Although PS has a high calorific value of 87 GJ
tonne-1, there is no a practical method to manage its waste but landfill. As a result, the
PS debris in the oceans has reached 70% of the total plastic debris. This issue is
considered as the main economical and environmental drivers of converting polystyrene
waste into renewable chemical feedstocks.
The aim of this work is to develop a catalyst for converting PS into renewable chemicals
under mild conditions. We introduce FeCu/Alumina with excellent catalytic activity to
fully degrade polystyrene with 66% liquid yield at 250 °C. The GC/MS confirmed that the
primary products are in the gasoline range. Next, we present the bimetallic
FeCo/Alumina and successfully we have obtained 100% PS conversion and 90% liquid
yield with maintaining the products
selectivity. Later, the tri-metallic FeCuCo/Alumina
was synthesized and showed 100% PS conversion and 91% liquid yield. Surprisingly,
ethylbenzene was the major product in which 80 wt. % was achieved with excellent
reproducibility. Furthermore, the real waste Styrofoam was thermally and catalytically
degraded at 250 °C. Interestingly, a high styrene content of 78 wt. % was recovered
after 30 minutes of the reaction under mild conditions. Keeping in mind that a good
balance between acidity and basicity is required to convert PS into aromatic under mild
reaction conditions catalytically. Finally, the performance of the catalysts was compared
to literature reports and showed novel liquid yields. In conclusion, we have synthesized
cheap, easy to scale up, and efficient catalysts to fully degrade PS into high liquid yields
of aromatics with excellent
selectivity.
Advisors/Committee Members: Huang, Kuo-Wei (advisor), Lai, Zhiping (committee member), Hadjichristidis, Nikos (committee member), Han, Yu (committee member), Rode. C.V (committee member).
Subjects/Keywords: Polystyrene; Ethylbenzene selectivity; Low-temperature; Catalytic degradation; Styrene selectivity; Renewable-aromatics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Al Jabri, N. M. (2017). Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/625826
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Al Jabri, Nouf M. “Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions.” 2017. Thesis, King Abdullah University of Science and Technology. Accessed February 27, 2021.
http://hdl.handle.net/10754/625826.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Al Jabri, Nouf M. “Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions.” 2017. Web. 27 Feb 2021.
Vancouver:
Al Jabri NM. Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2017. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10754/625826.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Al Jabri NM. Renewable Aromatics from the Degradation of Polystyrene under Mild Conditions. [Thesis]. King Abdullah University of Science and Technology; 2017. Available from: http://hdl.handle.net/10754/625826
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
18.
Measor, Kevin.
Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus.
Degree: Neuroscience, 2014, University of California – Riverside
URL: http://www.escholarship.org/uc/item/7r60520t
► Adaptations that allow for greater discrimination of low intensity sounds may be important in the echolocation behavior of bats. In this dissertation, we used the…
(more)
▼ Adaptations that allow for greater discrimination of low intensity sounds may be important in the echolocation behavior of bats. In this dissertation, we used the pallid bat, Antrozous pallidus, a gleaning bat of the western United States, as a model to study the adaptations for intensity selectivity present in the auditory cortex. We performed in-vivo extracellular recordings in the auditory cortex of the pallid bat, to determine the cortical organization and mechanisms of intensity selectivity. Downward frequency modulated (DFM) sweeps that approximated echolocation calls were used to study intensity selectivity using a behaviorally relevant sound. We also examined the distribution of Parvalbumin (PV) and Calbindin (CB) expressing cells in cortical regions and thalamic nuclei in the auditory pathway. Immunohistochemical staining was used to determine if the distribution of these calcium binding proteins in cortical and thalamic regions that have been implicated in processing of echolocation calls and how that distribution is different from non-echolocating regions. Lastly we examined the thalamocortical projections to intensity selective neurons in the echolocation region of the auditory cortex. Retrograde tracing from intensity selective and non-selective neurons was used to identify the thalamic nuclei that provided input to those neurons. We show that the region of the auditory cortex that is selective for echolocation calls contains a majority of neurons that are highly selective for low intensity sounds. We discovered that in the pallid bat intensity selectivity is enhanced by using behaviorally relevant stimuli and that high-frequency inhibition in the bat's echolocation call is responsible for this increased selectivity. This suggested a spectrotemporal integration mechanism that can shape intensity selectivity. Cortical mapping, in this study, revealed a systematic organization of intensity selectivity measures. We also discovered a differential staining pattern of calcium binding protein in the cortex as higher percentage of PV+ cells compared to CB+ cells was found in both echolocation call- and non-call regions. CB+ neurons where found in all of the regions of the medial geniculate body of the auditory thalamus, while PV staining was limited to the suprageniculate (SG), a region known to project to echolocation selective regions of the cortex. This study also confirmed previous results showing that echolocation selective regions of the cortex receive projections from all nuclei of the MGB except the lemniscal ventral nucleus, however an organization related to intensity selectivity was not able to be determined in the projections. The results from this dissertation highlight the special adaptations that are present in the auditory cortex of the pallid bat that may be important for processing the low-intensity echolocation call. Deviations from a general mammalian plan or even from other bat species in the properties that lead to these adaptations may strengthen the notion that…
Subjects/Keywords: Neurosciences; Bat; Cortex; Intensity; Pallid; Selectivity; Thalamocortical
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Measor, K. (2014). Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/7r60520t
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Measor, Kevin. “Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus.” 2014. Thesis, University of California – Riverside. Accessed February 27, 2021.
http://www.escholarship.org/uc/item/7r60520t.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Measor, Kevin. “Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus.” 2014. Web. 27 Feb 2021.
Vancouver:
Measor K. Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus. [Internet] [Thesis]. University of California – Riverside; 2014. [cited 2021 Feb 27].
Available from: http://www.escholarship.org/uc/item/7r60520t.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Measor K. Intensity Selectivity in the Auditory Cortex of the Pallid Bat, Antrozous pallidus. [Thesis]. University of California – Riverside; 2014. Available from: http://www.escholarship.org/uc/item/7r60520t
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
19.
Lipe, Star L.
An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders.
Degree: Applied Behavior Analysis: M.S., Community Psychology, Counseling and Family Therapy, 2015, St. Cloud State University
URL: https://repository.stcloudstate.edu/cpcf_etds/11
► Children with autism are frequently labeled as selective or “picky” eaters (Volkert & Vaz, 2010). The purpose of the current study was to evaluate…
(more)
▼ Children with autism are frequently labeled as selective or “picky” eaters (Volkert & Vaz, 2010). The purpose of the current study was to evaluate antecedent choice as an intervention for decreasing selective eating in children diagnosed with autism. The results show that choice as an antecedent intervention was not effective at increasing consumption of non-preferred foods for three children diagnosed with autism. Acceptance of non-preferred food was 0% in baseline for all participants and remained at 0% during choice between two non-preferred foods. A differential reinforcement of alternative behavior (DRA) component was added to the choice phase, but acceptance of the non-preferred bite remained at 0%. Discussion on possibilities for treatment failure and alternative interventions is provided.
Advisors/Committee Members: Kimberly Schulze, Benjamin Witts, Eric Rudrud.
Subjects/Keywords: choice; antecedent intervention; food selectivity; autism
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lipe, S. L. (2015). An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders. (Masters Thesis). St. Cloud State University. Retrieved from https://repository.stcloudstate.edu/cpcf_etds/11
Chicago Manual of Style (16th Edition):
Lipe, Star L. “An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders.” 2015. Masters Thesis, St. Cloud State University. Accessed February 27, 2021.
https://repository.stcloudstate.edu/cpcf_etds/11.
MLA Handbook (7th Edition):
Lipe, Star L. “An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders.” 2015. Web. 27 Feb 2021.
Vancouver:
Lipe SL. An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders. [Internet] [Masters thesis]. St. Cloud State University; 2015. [cited 2021 Feb 27].
Available from: https://repository.stcloudstate.edu/cpcf_etds/11.
Council of Science Editors:
Lipe SL. An Evaluation of the Efficacy of Antecedent Choice for Decreasing Food Selectivity in Children with Autism Spectrum Disorders. [Masters Thesis]. St. Cloud State University; 2015. Available from: https://repository.stcloudstate.edu/cpcf_etds/11
Vanderbilt University
20.
Yin, Shen.
Allosteric modulation of metabotropic glutamate receptors.
Degree: PhD, Pharmacology, 2013, Vanderbilt University
URL: http://hdl.handle.net/1803/14819
► Metabotropic glutamate receptors (mGlus) are a group of Family C Seven Transmembrane Spanning Receptors that play important roles in modulating signaling transduction, particularly within the…
(more)
▼ Metabotropic glutamate receptors (mGlus) are a group of Family C Seven Transmembrane Spanning Receptors that play important roles in modulating signaling transduction, particularly within the central nervous system. mGlu4 belongs to a subfamily of mGlus that is coupled to Gi/o G proteins, and represents a promising target for the treatment of Parkinson’s disease. Allosteric modulators of mGlu4 provide several advantages over the orthosteric ligands in terms of drug discovery. However, the complicated pharmacology of allosteric modulators remain largely unexplored. The ubiquitous autacoid and neuromodulator, histamine, biases the signaling of small molecule positive allosteric modulators of mGlu4 toward calcium-dependent pathways via concomitant activation of histamine H1 receptor. These results suggest that allosteric modulators may exhibit functional selective effects in the presence of signaling convergence. In addition, mGlu2 and mGlu4 form a hetero-complex in native brain tissues, and differentially regulate the efficacies of allosteric modulators in cell lines and at the corticostriatal synapse. These data greatly extend our current understanding of mGlu receptor interaction and function and shed light on the development of allosteric modulators for tissue-specific therapy.
Advisors/Committee Members: Richard M. Breyer (committee member), Roger J. Colbran (committee member), Danny G. Winder (committee member), P. Jeffrey Conn (committee member), Colleen M. Niswender (committee member), Vsevolod V. Gurevich (Committee Chair).
Subjects/Keywords: heterodimerization; functional selectivity; pharmacology; allosteric modulators; mGlu
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Yin, S. (2013). Allosteric modulation of metabotropic glutamate receptors. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14819
Chicago Manual of Style (16th Edition):
Yin, Shen. “Allosteric modulation of metabotropic glutamate receptors.” 2013. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2021.
http://hdl.handle.net/1803/14819.
MLA Handbook (7th Edition):
Yin, Shen. “Allosteric modulation of metabotropic glutamate receptors.” 2013. Web. 27 Feb 2021.
Vancouver:
Yin S. Allosteric modulation of metabotropic glutamate receptors. [Internet] [Doctoral dissertation]. Vanderbilt University; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1803/14819.
Council of Science Editors:
Yin S. Allosteric modulation of metabotropic glutamate receptors. [Doctoral Dissertation]. Vanderbilt University; 2013. Available from: http://hdl.handle.net/1803/14819
Queens University
21.
Peng, Bolu.
Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
.
Degree: Chemistry, 2015, Queens University
URL: http://hdl.handle.net/1974/13528
► Crosslinking monomers or a polymer around template molecules and the subsequent removal of the templates yield a polymer matrix containing cavities that resemble the shape…
(more)
▼ Crosslinking monomers or a polymer around template molecules and the subsequent removal of the templates yield a polymer matrix containing cavities that resemble the shape of the templates and bear binding groups that complement those on the template molecules. However, a key challenge facing those molecularly imprinted polymers (MIPs) is the infidelity of the pores generated to the original templates and thus non-specific binding of the pores to analytes other than the template. I report in this thesis a method to improve the selectivity of MIP particles.
I prepared an MIP for a chiral analyte relying not only on the traditional H-bonding interactions between the polymer matrix and the template but also on the - stacking interactions. Specifically, I synthesized a novel diblock copolymer poly(ethylene oxide)226-block-poly[(2-pentafluorocinnamoyloxyethyl methacrylate)75%-ran-[2-(2’-carboxybenzoyloxy)ethyl methacrylate]25%]100 or PEO226-b-P(FEMA75%-r-CA25%)100. While the CA groups were introduced because of their H-bond interactions with carbonyl oxygen and amino group of the chiral template D-phenylalanine anilide, the FEMA units were introduced for their ability to crosslink under the UV irradiation and also for the π-π stacking interactions of the fluorinated FEMA phenyl rings with the phenyl rings of D-phenylalanine anilide. To prepare MIP nanoparticles, I first dispersed the diblock copolymer and D-phenylalanine anilide in chloroform/methanol at 95 vol% of methanol to prepare micelles that bore PEO coronal chains and a P(FEMA-r-CA) core that complexed with D-phenylalanine anilide. I then photocrosslinked the micellar core and locked the FEMA and CA units around the template molecules. In a third step, I extracted out D-phenylalanine anilide using a solvent. I discovered that these crosslinked MIP nanoparticles had a selectivity of 6.3 towards the binding of D-phenylalanine anilide over L-phenylalanine anilide. This represented a 70% increase in selectivity of MIP nanoparticles prepared from an analogous approach by replacing PEO226-b-P(FEMA75%-r-CA25%)100 with PEO226-b-P(CEMA75%-r-CA25%)100, where CEMA is the hydrogenated version of FEMA. I believe that my work pinpoints the opportunity for using π-π stacking interactions between fluorinated and hydrogenated aromatic rings for improving the selectivity of MIPs and the potential of using this interaction in future for developing highly selective MIPs.
Subjects/Keywords: diblock copolymer
;
MIPs
;
selectivity
;
self-assembly
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Peng, B. (2015). Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/13528
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Peng, Bolu. “Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
.” 2015. Thesis, Queens University. Accessed February 27, 2021.
http://hdl.handle.net/1974/13528.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Peng, Bolu. “Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
.” 2015. Web. 27 Feb 2021.
Vancouver:
Peng B. Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
. [Internet] [Thesis]. Queens University; 2015. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1974/13528.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Peng B. Synthesis of a Novel Diblock Copolymer and Preparation of Highly Selective Molecularly Imprinted Polymer Nanospheres from It
. [Thesis]. Queens University; 2015. Available from: http://hdl.handle.net/1974/13528
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Queens University
22.
Dafoe, Julian.
Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
.
Degree: Chemical Engineering, 2014, Queens University
URL: http://hdl.handle.net/1974/8575
► This thesis investigated polymer properties for their application as extractants in two-phase partitioning bioreactors (TPPBs), which are intended to remove inhibitory fermentation products as they…
(more)
▼ This thesis investigated polymer properties for their application as extractants in two-phase partitioning bioreactors (TPPBs), which are intended to remove inhibitory fermentation products as they are produced. Three applications of polymer TPPB extractants were studied, followed by an investigation into poly(ether)-based polymers’ affinity toward representative target molecules, to identify properties which confer improved extraction performance.
The first investigation aimed to replace a liquid extractant (silicone oil) using a block copolymer, Hytrel® 8206, in the biotransformation of indene to cis-(1S,2R)-indandiol, a chiral pharmaceutical intermediate, by Pseudomonas putida ATCC55687. The polymer simultaneously delivered substrate and removed the product and by-products to alleviate inhibition, improving operability and productivity relative to silicone oil, which could only deliver substrate. Subsequently, soft segment composition and proportion were varied in different block copolymers to selectively extract product or by-product(s) from the same biotransformation, altering the cells’ production profile. This demonstrated selective polymer extraction to help direct substrate utilization toward the product rather than by-product(s) in complex biotransformations.
The next study was on absorptive extraction of a hydrophilic target molecule, 4-valerolactone, produced by recombinant Pseudomonas putida KT2440, featuring an equilibrium-limited final step. The aim was to demonstrate the first application of equilibrium-pulling using selective product absorption, improving production by 30%. Furthermore, this study showed that limited polymer water absorption is helpful to aid in extraction of hydrophilic target molecules, but high polymer water content compromises selectivity, diminishing the equilibrium-pulling effect.
Finally, the effects of soft block proportion, molecular weight, and chain-end composition on affinity toward representative target molecules, carveol and carvone, were studied using commercial block copolymers and their representative homopolymer components. Target molecule affinity improved at low molecular weights in the absence of polar homopolymer end-groups. End-group polarity had an effect whose direction depended on the polarity of the target molecule, improving affinity toward a third, polar target molecule, 4-valerolactone, thereby providing a means to tailor selectivity. Crystallinity and hard segment proportion were both found to reduce uptake.
This work has provided insights into the selection of polymeric TPPB absorbents by identifying polymer properties which improve affinity and selectivity toward different fermentation target molecules, especially relatively hydrophilic ones. The future design of purpose-built polymer extractants will benefit from considering these findings.
Subjects/Keywords: Polymer
;
Absorption
;
Partitioning
;
Bioreactors
;
Selectivity
;
Biocatalysis
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Dafoe, J. (2014). Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/8575
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Dafoe, Julian. “Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
.” 2014. Thesis, Queens University. Accessed February 27, 2021.
http://hdl.handle.net/1974/8575.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Dafoe, Julian. “Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
.” 2014. Web. 27 Feb 2021.
Vancouver:
Dafoe J. Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
. [Internet] [Thesis]. Queens University; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1974/8575.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Dafoe J. Properties of Absorbent Polymer Extractants for the Selective Removal of Target Molecules from Fermentation Systems
. [Thesis]. Queens University; 2014. Available from: http://hdl.handle.net/1974/8575
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Uppsala University
23.
Bruce, Henrik.
Formulation of Model Problem for Chirality Induced Spin Selectivity Effect.
Degree: Materials Theory, 2020, Uppsala University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414026
► Spin dependent electron transport in chiral molecules, the so-called chirality induced spin selectivity (CISS) effect, have attracted much attention over the past few years.…
(more)
▼ Spin dependent electron transport in chiral molecules, the so-called chirality induced spin selectivity (CISS) effect, have attracted much attention over the past few years. Experimentally the spin polarization has been detected, and there is a theoretical consensus on the necessity of both spin-orbit coupling and geometrical helicity in order to get a non-vanishing spin polarization. Several model Hamiltonians has been proposed to describe the CISSS effect, and while they can yield spin polarization agreeing with the experimentally observed magnitudes, they are relying on unrealistic values of the spin orbit interaction parameters. In recent years the importance of electron correlation has been emphasized. Thus, this thesis presents the general theory on how to treat the CISS effect as a many body problem, taking electron correlation into account. The Hamiltonian modelling is described and one approach on how to treat the helical structure of the molecule and the spin-orbit coupling is presented. Building on this thesis, further studies will hopefully lead to a first principle understanding of the CISS effect.
Subjects/Keywords: Chirality; Spin selectivity; CISS; Physical Sciences; Fysik
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bruce, H. (2020). Formulation of Model Problem for Chirality Induced Spin Selectivity Effect. (Thesis). Uppsala University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414026
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bruce, Henrik. “Formulation of Model Problem for Chirality Induced Spin Selectivity Effect.” 2020. Thesis, Uppsala University. Accessed February 27, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414026.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bruce, Henrik. “Formulation of Model Problem for Chirality Induced Spin Selectivity Effect.” 2020. Web. 27 Feb 2021.
Vancouver:
Bruce H. Formulation of Model Problem for Chirality Induced Spin Selectivity Effect. [Internet] [Thesis]. Uppsala University; 2020. [cited 2021 Feb 27].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414026.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bruce H. Formulation of Model Problem for Chirality Induced Spin Selectivity Effect. [Thesis]. Uppsala University; 2020. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414026
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
24.
Obbo, Jovent K.
Men's perception of women and women's self-image in Lusaka, Zambia.
Degree: 2012, University of Zimbabwe
URL: http://dspace.unza.zm/handle/123456789/1724
► There has been a growing concern on the situation of women particularly because of the conscientization , which resulted from the UN women's decade (1976-85)…
(more)
▼ There has been a growing concern on the situation of women particularly because of the conscientization , which resulted from the UN women's decade (1976-85) with its themes, "peace", "development" and "equality". Various reasons have been given for the failure to improve on the situation of women. One of them has been the persistence of traditional attitudes towards them. This study was an attempt to examine the above issue. It looked at both men's perception of women and women's self-image in the Zambian context.The main objectives of the study were to identify how women are perceived by men in the Zambian context; examine whether men's perception of women is influenced by the variables of age, education, marital status, income and place of residence; identify how women in Zambia perceive themselves; find out the relationship between men's perception of women and women's self-image; and whether women's self-image is influenced by the variables of age, education, marital status, place of residence and income. The following were hypothesized: men have a negative perception of women in terms of socio-economic status; women have a negative self-image in terms of socio-economic status; men's perception of women and women's self-image are positively ?^elated to the variables of age, marital status, education, income and place of residence; men's perception of women is positively related to women's self-image.
The study employed the survey design. Data was collected from 200 male and female residents of Lusaka urban. These were Zambian citizens of twenty-one years and above. The person to person interview was utilized. Computer techniques were used to process and analyse the data. In the analysis frequencies, percentages, cross tabulations and correlations (Pearsons Chi-square) were used.
The main findings of the survey were that women in Lusaka, Zambia are generally positively perceived by men and they have a positive self-image, in terms of socio-economic status. This finding did not support the theoretical hypotheses that (1) "men have a negative perception of women" (2) women have a negative-self-image in terms of socio-economic status". The findings partly failed to confirm the hypothesis that "men's perception of women and women's self-image are related to the variables of age and marital status, education, income and residence as mixed results were obtained.
Finally, it was recommended that more education opportunities for women be promoted; agents of socialization be sensitized to socialize members of the society in a way that will make them have high regard for women; efforts be made to have more women in higher occupations in the public sphere; restrictive policies which hinder women's involvement in the public sphere be removed and that future studies concentrate on how culture affects perception of women in Lusaka, Zambia.
Subjects/Keywords: Self Perception; Perception; Social Perception; Selectivity(Psychology)
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Obbo, J. K. (2012). Men's perception of women and women's self-image in Lusaka, Zambia. (Thesis). University of Zimbabwe. Retrieved from http://dspace.unza.zm/handle/123456789/1724
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Obbo, Jovent K. “Men's perception of women and women's self-image in Lusaka, Zambia.” 2012. Thesis, University of Zimbabwe. Accessed February 27, 2021.
http://dspace.unza.zm/handle/123456789/1724.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Obbo, Jovent K. “Men's perception of women and women's self-image in Lusaka, Zambia.” 2012. Web. 27 Feb 2021.
Vancouver:
Obbo JK. Men's perception of women and women's self-image in Lusaka, Zambia. [Internet] [Thesis]. University of Zimbabwe; 2012. [cited 2021 Feb 27].
Available from: http://dspace.unza.zm/handle/123456789/1724.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Obbo JK. Men's perception of women and women's self-image in Lusaka, Zambia. [Thesis]. University of Zimbabwe; 2012. Available from: http://dspace.unza.zm/handle/123456789/1724
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
25.
Sierra Castillo, Liliana Paola.
Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras.
Degree: MS, Wildlife and Fisheries Sciences, 2019, Texas A&M University
URL: http://hdl.handle.net/1969.1/188798
► Small-scale fisheries are difficult to assess and manage adequately due to uncertainties surrounding collected data. For example, data are often limited to fishery-dependent data, and…
(more)
▼ Small-scale fisheries are difficult to assess and manage adequately due to uncertainties surrounding collected data. For example, data are often limited to fishery-dependent data, and fishing gear, such as a gillnet, is very size-selective. This makes the estimation of important parameters such as total mortality and natural mortality difficult, and thus fishery assessment is challenging. Despite these difficulties, management decisions must be made with the available information. The objectives of this thesis were to estimate the total and natural mortality of Lane Snapper (Lutjanus synagris) in the coastal waters of Honduras and determine if the length metric method can be utilized for assessment of this fishery. The total mortality was estimated using a regression catch-curve analysis applied to fishery-dependent catch per unit effort (CPUE) data. The method accounted for gear
selectivity by fitting multiple gear-
selectivity curves and determining the best curve using a statistical model selection method. The estimated mortality was compared with other estimates obtained without using a regression catch-curve analysis. The natural mortality was estimated using four different methods; these methods included the Peterson and Wroblewski, Lorenzen, and Sekharan estimators as well as using the “Fish Life” R package. Then, fishing mortality was estimated by subtracting natural mortality from the total mortality. Our results showed that the skewed normal
selectivity curve fit the data best. The total mortality estimates were higher compared with other estimates when the CPUE was not corrected for gear
selectivity. The natural mortality was consistent among three of the different methods employed, with the exception being the Peterson & Wroblewski estimator.
When estimating the fishing mortality, more variation came from total mortality compared to natural mortality. This study also demonstrates the importance of using multiple estimators for total and natural mortality to assess uncertainties associated with models and the underlying data. The three indicators proposed by Froese were estimated with and without accounting for size-
selectivity of the gill nets, and then the resulting indicators were compared. The estimation of the different indicators suggest that the fishery is experiencing recruitment overfishing and growth overfishing is also occurring. My results suggest that the indicators proposed by Froese can be over- or under-estimated when gear
selectivity is not taken into account.
Advisors/Committee Members: Fujiwara, Masami (advisor), Woodward, Richard (committee member), Perkin, Joshuah (committee member).
Subjects/Keywords: Small-scale fisheries; Gill net selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sierra Castillo, L. P. (2019). Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/188798
Chicago Manual of Style (16th Edition):
Sierra Castillo, Liliana Paola. “Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras.” 2019. Masters Thesis, Texas A&M University. Accessed February 27, 2021.
http://hdl.handle.net/1969.1/188798.
MLA Handbook (7th Edition):
Sierra Castillo, Liliana Paola. “Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras.” 2019. Web. 27 Feb 2021.
Vancouver:
Sierra Castillo LP. Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras. [Internet] [Masters thesis]. Texas A&M University; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1969.1/188798.
Council of Science Editors:
Sierra Castillo LP. Improving the Assessment of the Lane Snapper (Lutjanus synagris) in a Small-Scale Fishery in Honduras. [Masters Thesis]. Texas A&M University; 2019. Available from: http://hdl.handle.net/1969.1/188798
University of Debrecen
26.
Barcsa, Lajos.
State Aid in the European Union
.
Degree: DE – Állam- és Jogtudományi Kar, University of Debrecen
URL: http://hdl.handle.net/2437/241352
A szakdolgozat az Európai Unióról szóló szerződés 107. cikkelyének részletes elemzését tartalmazza. Kifejtésre kerülnek benne az általános gazdasági érdekű szolgáltatások, a szelektivitás elmélete, a piacgazdasági befektető elve. Részletesen bemutatásra kerülnek a megengedett és a megengedhető állami támogatások.
Advisors/Committee Members: Bartha, Ildikó (advisor).Subjects/Keywords: state aid; selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Barcsa, L. (n.d.). State Aid in the European Union
. (Thesis). University of Debrecen. Retrieved from http://hdl.handle.net/2437/241352
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Barcsa, Lajos. “State Aid in the European Union
.” Thesis, University of Debrecen. Accessed February 27, 2021.
http://hdl.handle.net/2437/241352.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Barcsa, Lajos. “State Aid in the European Union
.” Web. 27 Feb 2021.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Vancouver:
Barcsa L. State Aid in the European Union
. [Internet] [Thesis]. University of Debrecen; [cited 2021 Feb 27].
Available from: http://hdl.handle.net/2437/241352.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
Council of Science Editors:
Barcsa L. State Aid in the European Union
. [Thesis]. University of Debrecen; Available from: http://hdl.handle.net/2437/241352
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
Boston College
27.
Sun, Xixi.
Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules.
Degree: PhD, Chemistry, 2013, Boston College
URL: http://dlib.bc.edu/islandora/object/bc-ir:101487
► Chapter 1. We reported the first synthesis of all-carbon quaternary centers via hydroformylations using a catalytic directing group. With the ability of reversibly and covalently…
(more)
▼ Chapter 1. We reported the first synthesis of
all-carbon quaternary centers via hydroformylations using a
catalytic directing group. With the ability of reversibly and
covalently binding to a substrate, and coordinating to a metal
center, scaffolding catalyst 1.1 is able to direct the
branch-selective hydroformylation of 1,1-disubstituted olefins
under mild temperature. Chapter 2. We have designed and synthesized
a chiral organocatalyst 2.11. This catalyst is able to covalently
bind to one hydroxyl, and utilize the induced intramolecularity to
stereoselectively functionalize the other hydroxyl within a
cis-1,2-diol via electrophile transfer. Catalyst 2.11 was used in
the desymmetrization of meso-1,2-diols under mild conditions (4 C
to room temperature), leading to high yields and selectivities for
a broad substrate scope. Chapter 3. Catalyst 3.1 and 3.6 were
demonstrated to selectively bind to primary hydroxyls over
secondary hydroxyls. By combining the binding
selectivity with
asymmetric catalysis, these scaffolding catalysts were shown to
promote the selective silylation of secondary hydroxyls within
terminal (S)-1,2-diols. The reversal of substrate bias was further
applied to a regiodivergent kinetic resolution of racemic terminal
1,2-diols, producing secondary protected products in synthetically
practical levels of enantioselectivity (>95:5 er) and yields
(≥40%). Time course studies of this reaction further revealed the
optimal condition to form the primary silylated product in high
s-factor. Chapter 4. Based on the previous understanding of
catalyst 4.5 and 4.6, the exclusive catalyst recognition of
cis-1,2-diols within polyhydroxylated molecules was further
discovered. This unique functional group display recognition was
further allied with the catalyst's ability to stereoselectively
differentiate hydroxyls within cis-1,2-diols, enabling the
site-selective protection, functionalization, and activation of the
inherently less reactive axial hydroxyl groups within
carbohydrates. This methodology also enables the selective
functionalization of multiple complex molecules, including digoxin,
mupirocin, and ribonucleosides, demonstrating the potential power
of scaffolding catalysis in the rapid access to valuable synthetic
derivatives of polyhydroxylated compounds.
Advisors/Committee Members: Kian L. Tan (Thesis advisor).
Subjects/Keywords: Carbohydrate; Hydroformylation; Polyhydroxylated; Scaffolding Catalysis; Site-Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sun, X. (2013). Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101487
Chicago Manual of Style (16th Edition):
Sun, Xixi. “Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules.” 2013. Doctoral Dissertation, Boston College. Accessed February 27, 2021.
http://dlib.bc.edu/islandora/object/bc-ir:101487.
MLA Handbook (7th Edition):
Sun, Xixi. “Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules.” 2013. Web. 27 Feb 2021.
Vancouver:
Sun X. Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules. [Internet] [Doctoral dissertation]. Boston College; 2013. [cited 2021 Feb 27].
Available from: http://dlib.bc.edu/islandora/object/bc-ir:101487.
Council of Science Editors:
Sun X. Scaffolding Catalysis: Towards Regioselective
Hydroformylation of Alkenes and Site-Selective Functionalization of
Polyhydroxylated Molecules. [Doctoral Dissertation]. Boston College; 2013. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101487
University of Cambridge
28.
Curk, Tine.
Modelling multivalent interactons.
Degree: PhD, 2016, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/266916
► A Multivalent entity, which could represent a protein, nanoparticle, polymer, virus or a lipid bilayer, has the ability to form multiple bonds to a substrate.…
(more)
▼ A Multivalent entity, which could represent a protein, nanoparticle, polymer, virus or a lipid bilayer, has the ability to form multiple bonds to a substrate. Hence, a multivalent interaction can be strong, even if the individual bonds are weak. However, much more interestingly, multivalency enables the design of highly specific interactions using non-specific individual bonds. We attempt to rationalise multivalent effects using simple physical models complemented with numerical simulations. Based on physiochemical characteristics of multivalent binders, we aim to predict the overall strength of interaction and its sensitivity to variation in parameters.
We start with a simple model of homo-multivalency, where all bonds are equivalent. Such systems can exhibit a super-selective response, which denotes the high sensitivity of the strength of multivalent binding to the number of accessible binding sites on the target surface. We present a theoretical analysis of systems of multivalent particles and show that a certain degree of disorder is necessary for super-selective behaviour. Moreover, we formulate a set of simple design rules for multivalent interactions that yield optimal selectivity.
In the second stage, we expand the model to hetero-multivalency, accounting for multiple distinct types of binding partners. We consider targeting of cells based on a density profile of different membrane receptors types and demonstrate, that speci city towards a desired receptor density profile can be obtained. Hence, cells can be reliably targeted in the absence of specific markers. Crucially, we show that for optimal selectivity, individual bonds must be weak.
Finally, we add information about specific geometry and positions of binding sites on the multivalent entity. We focus on molecular imprinting; the process whereby a polymer matrix is cross-linked in the presence of template molecules. The cross-linking process endows the polymer matrix with a chemical ‘memory’, such that the target molecules can subsequently be recognised by the matrix. We show how the binding multivalency and the polymer material properties affect the efficiency and selectivity of molecular imprinting.
Subjects/Keywords: multivalency; selectivity; Monte Carlo simulations; statistical mechanics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Curk, T. (2016). Modelling multivalent interactons. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/266916
Chicago Manual of Style (16th Edition):
Curk, Tine. “Modelling multivalent interactons.” 2016. Doctoral Dissertation, University of Cambridge. Accessed February 27, 2021.
https://www.repository.cam.ac.uk/handle/1810/266916.
MLA Handbook (7th Edition):
Curk, Tine. “Modelling multivalent interactons.” 2016. Web. 27 Feb 2021.
Vancouver:
Curk T. Modelling multivalent interactons. [Internet] [Doctoral dissertation]. University of Cambridge; 2016. [cited 2021 Feb 27].
Available from: https://www.repository.cam.ac.uk/handle/1810/266916.
Council of Science Editors:
Curk T. Modelling multivalent interactons. [Doctoral Dissertation]. University of Cambridge; 2016. Available from: https://www.repository.cam.ac.uk/handle/1810/266916
29.
Srikant, Sriram.
Evolution of Substrate Selectivity in ATP Binding Cassette Exporters.
Degree: PhD, 2019, Harvard University
URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42013160
► ATP binding cassette proteins represent the largest super-family of primary transporters with homologous sequences present in all extant organisms, coordinating the hydrolysis of ATP in…
(more)
▼ ATP binding cassette proteins represent the largest super-family of primary transporters with homologous sequences present in all extant organisms, coordinating the hydrolysis of ATP in nucleotide binding domains (NBDs) with the transport of substrates across biological membranes through transmembrane domains (TMDs). Type I ABC exporters are a large sub-family of ABC proteins that play a role in the unidirectional transport of substrates from the cytosol to the extracellular space or organelle lumens. Paralogous exporters have evolved to transport a wide variety of substrates across evolution like LPS in gram-negative bacteria, intermediates for cytosolic Fe-S cluster synthesis in eukaryotes and antigenic peptides in adaptive immunity of Vertebrates. The evolutionary flexibility of substrate selectivity in type I ABC exporters is particularly interesting given the structural and mechanistic similarity across paralogs. My doctoral work took advantage of a type I exporter that plays the role of a dedicated pheromone exporter in fungal mating to address the open question of substrate selectivity in exporters. Fungal mating has pairs of lipidated peptide pheromones and dedicated ABC exporters conserved across 500 million years of evolution. The sequences of peptide pheromones change across the fungal lineage leading to co-evolution of exporters with their cognate pheromone substrates.
The ability to grow dense populations rapidly and powerful genetics make the baker’s yeast, S. cerevisiae an ideal model organism to build experimental systems that test functional variation in proteins. We built an experimental system that quantitatively couples the pheromone export activity of an expressed ABC exporter to a fluorescent reporter in the same cell. Starting from a mutated set of a non-functional orthologous exporter, we selected for increased pheromone export based on fluorescence of the cells. Our work shows that there is a large target size for mutations that affect substrate selectivity of ABC exporters. A large target size with additive contributions of individual mutations might explain the evolutionary success of ABC exporters. Specifically, a large target size would provide high probability trajectories for duplication and divergence of a transporter to transport “novel” substrates.
Increasing availability of sequenced genomes of fungi also provides a library of substrates (pheromones) and exporters to test the model for co-evolution. Orthologous pheromone exporters can be identified by homology search, while pheromones candidates can be identified by an algorithmic sieve that we have developed. Going forward, our experimental selection system can enable comparisons of phylogenetic variation in pheromone exporters we observe by imposing artificial selection.
Biology, Molecular and Cellular
Advisors/Committee Members: Kahne, Daniel (advisor), Denic, Vlad (committee member), Hekstra, Doeke (committee member).
Subjects/Keywords: ABC Exporters; Yeast; Substrate selectivity; Artificial selection
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Srikant, S. (2019). Evolution of Substrate Selectivity in ATP Binding Cassette Exporters. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:42013160
Chicago Manual of Style (16th Edition):
Srikant, Sriram. “Evolution of Substrate Selectivity in ATP Binding Cassette Exporters.” 2019. Doctoral Dissertation, Harvard University. Accessed February 27, 2021.
http://nrs.harvard.edu/urn-3:HUL.InstRepos:42013160.
MLA Handbook (7th Edition):
Srikant, Sriram. “Evolution of Substrate Selectivity in ATP Binding Cassette Exporters.” 2019. Web. 27 Feb 2021.
Vancouver:
Srikant S. Evolution of Substrate Selectivity in ATP Binding Cassette Exporters. [Internet] [Doctoral dissertation]. Harvard University; 2019. [cited 2021 Feb 27].
Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42013160.
Council of Science Editors:
Srikant S. Evolution of Substrate Selectivity in ATP Binding Cassette Exporters. [Doctoral Dissertation]. Harvard University; 2019. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42013160
University of Manchester
30.
Eichler, Anja.
Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity.
Degree: PhD, 2016, University of Manchester
URL: https://www.research.manchester.ac.uk/portal/en/theses/investigations-of-selfsufficient-p450cam-monooxygenases-for-activity-and-enantioselectivity(27df0fa8-b671-4593-8ec0-f993a31e120c).html
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728108
► Catalytic, selective C-H bond activation for the oxidative hydroxylation RH → ROH of simple or complex compounds is of significant interest in synthetic organic chemistry.…
(more)
▼ Catalytic, selective C-H bond activation for the oxidative hydroxylation RH → ROH of simple or complex compounds is of significant interest in synthetic organic chemistry. One of the major classes of enzymes used for C-H bond activation are cytochrome P450 monooxygenases (EC 1.14.X.X), which can promote chemo-, regio- and stereoselective oxidations under mild reaction conditions. For the current study, catalytically self-sufficient forms of biocatalyst P450cam-RhFRed were investigated. These self-sufficient P450 systems were previously created by fusing the reductase domain of P450 RhF (CYP116B2, RhFRed from Rhodococcus sp.) with the catalytic domain of P450cam (CYP101A1, Pseudomonas putida), thus mimicking the natural fusion of P450 RhF. The generation of 93 P450cam-RhFRed variants has expanded the synthetic toolbox to serve as a basis for exploring the substrate scope towards ethylbenzenes, substituted alkylbenzenes, 4-ethylphenol and (+)-pleuromutilin. To select for active mutants from this library of 93, high throughput screening methods were developed. A pooling approach was applied in order to express P450s and analyse them against a panel of non-natural substrates, such as ethylbenzene, 4-ethylphenol and (+)-pleuromutilin in whole cell biotransformation reactions. The concentration of P450 enzymes was determined using CO difference spectroscopy in whole cells. The assay was significantly improved both in terms of speed and safety by using carbon monoxide releasing molecules as a source of CO rather than the gas CO itself. These screening studies served as starting point to identify P450cam-RhFRed mutants for specific reactions. In particular, a systematic investigation of this library showed mutants that generated chiral benzyl alcohols with good enantioselectivities. To interpret these results on a structural basis, molecular dynamics simulations were used to estimate enantioselectivity of selected mutants for the regio-isomers of methylated ethylbenzene derivatives. The results from the molecular dynamics simulations were broadly consistent with experimentally determined data and identified the importance of conformational changes and flexibility of mutant-substrate complexes to enforce enantioselectivity.
Subjects/Keywords: 572; C-H activation; P450 enzymes; Selectivity
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Eichler, A. (2016). Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/investigations-of-selfsufficient-p450cam-monooxygenases-for-activity-and-enantioselectivity(27df0fa8-b671-4593-8ec0-f993a31e120c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728108
Chicago Manual of Style (16th Edition):
Eichler, Anja. “Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity.” 2016. Doctoral Dissertation, University of Manchester. Accessed February 27, 2021.
https://www.research.manchester.ac.uk/portal/en/theses/investigations-of-selfsufficient-p450cam-monooxygenases-for-activity-and-enantioselectivity(27df0fa8-b671-4593-8ec0-f993a31e120c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728108.
MLA Handbook (7th Edition):
Eichler, Anja. “Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity.” 2016. Web. 27 Feb 2021.
Vancouver:
Eichler A. Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2021 Feb 27].
Available from: https://www.research.manchester.ac.uk/portal/en/theses/investigations-of-selfsufficient-p450cam-monooxygenases-for-activity-and-enantioselectivity(27df0fa8-b671-4593-8ec0-f993a31e120c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728108.
Council of Science Editors:
Eichler A. Investigations of self-sufficient P450cam monooxygenases for activity and enantioselectivity. [Doctoral Dissertation]. University of Manchester; 2016. Available from: https://www.research.manchester.ac.uk/portal/en/theses/investigations-of-selfsufficient-p450cam-monooxygenases-for-activity-and-enantioselectivity(27df0fa8-b671-4593-8ec0-f993a31e120c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728108
◁ [1] [2] [3] [4] [5] … [26] ▶
. 
Open Access Theses and Dissertations
