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You searched for subject:( guas subterr neas). Showing records 1 – 3 of 3 total matches.

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1. Mcgee, Benjamin Wright. Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering.

Degree: MS, Space Studies, 2018, University of North Dakota

Recent research suggests that ion bombardment is more effective than micrometeoroid bombardment in albedo darkening of mature lunar soils, whereas micrometeoroid bombardment may act on longer timescales and is more effective in modifying the spectral features of a surface. This, in turn, may be extrapolated to suggest the following: 1) Increased intensities of ion bombardment would correlate negatively with the surface reflectivity of airless, silicate-bearing bodies known to express lunar-style space weathering, such as S-type asteroids, and 2) beyond that of sputtering and ion implantation, there is a gradient of potential interactions between the two weathering processes that may be relevant to space weathering at large, where via the processes of mineral metamictization and structural weakening, ion bombardment may act as a necessary precursor to micrometeroid bombardment in lunar-style space weathering. Because heliosphere research (i.e., the Ulysses spacecraft) reveals that the speed of solar wind rises with solar latitude from the equatorial plane to the poles, the possibility of a correlation is suggested between the albedo of a given S-type asteroid surface and its orbital inclination. In other words, more highly-inclined asteroids would be exposed to higher-intensity solar ion bombardment, which would thereby result in darker (or more quickly darkened) mature surfaces. This proposition is explored via the statistical analysis of a sample group of S-complex airless bodies, resulting in a statistically-significant negative correlation between orbital inclination and albedo at the 75% confidence level. An overall space-weathering scheme is proposed, and implications for space weathering mechanisms as they relate to orbital parameters are discussed. Advisors/Committee Members: Michael J. Gaffey.

Subjects/Keywords: airless bodies; asteroids; NEAs; space weather; space weathering; surficial processes

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mcgee, B. W. (2018). Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering. (Masters Thesis). University of North Dakota. Retrieved from https://commons.und.edu/theses/2283

Chicago Manual of Style (16th Edition):

Mcgee, Benjamin Wright. “Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering.” 2018. Masters Thesis, University of North Dakota. Accessed February 16, 2020. https://commons.und.edu/theses/2283.

MLA Handbook (7th Edition):

Mcgee, Benjamin Wright. “Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering.” 2018. Web. 16 Feb 2020.

Vancouver:

Mcgee BW. Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering. [Internet] [Masters thesis]. University of North Dakota; 2018. [cited 2020 Feb 16]. Available from: https://commons.und.edu/theses/2283.

Council of Science Editors:

Mcgee BW. Determining The Correlation Significance Between S-Type Asteroid Orbital Inclination And Albedo Attributable To Space Weathering. [Masters Thesis]. University of North Dakota; 2018. Available from: https://commons.und.edu/theses/2283


Texas A&M University

2. Ge, Shen. Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation.

Degree: 2011, Texas A&M University

The development of the Surface Albedo Treatment System (SATS) onboard a spacecraft mission to the near earth asteroid (NEA) Apophis in 2012 is an innovative concept of deflecting NEAs from possible impact with the Earth through altering the Yarkovsky effect, a non-secular force in the solar system due to uneven surface thermal emission most profoundly affecting small rotating bodies subjected to sunlight. Though this force is small, its magnitude can be dramatic if extended over a period of time and if it uses the close approach of an asteroid near Earth to magnify the perturbation. The payload dispenses colored powder called albedo changing particles (ACPs) onto the surface changing its albedo and indirectly the surface temperature which changes the Yarkovsky effect. This study gives an in-depth description of both computational and experimental parts of the design of this system with primary focus on initial ground test setup. The initial experiments proposed to design the SATS is outlined in detail and justified by the mission criterion of interest as well as modeling the actual dispersal on the surface. Advisors/Committee Members: Hyland, David (advisor), Turner, James (committee member), Boyd, Jim (committee member), Ehsani, Mehrdad (committee member).

Subjects/Keywords: albedo; Apophis; armageddon; asteroids; deflection; NEOs; NEAs; space mission; tribodispenser; Yarkovsky effect; YORP

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Ge, S. (2011). Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10184

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):

Ge, Shen. “Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation.” 2011. Thesis, Texas A&M University. Accessed February 16, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10184.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Ge, Shen. “Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation.” 2011. Web. 16 Feb 2020.

Vancouver:

Ge S. Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation. [Internet] [Thesis]. Texas A&M University; 2011. [cited 2020 Feb 16]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10184.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ge S. Design of a Surface Albedo Modification Payload for Near Earth Asteroid (NEA) Mitigation. [Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10184

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Pinheiro, Carlos Danniel Freitas. Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas.

Degree: 2017, Universidade Federal do Amazonas

Altera??es patol?gicas cut?neas tais como impetigo, acne, erisipela, celulite e fur?nculo s?o causados por agentes microbianos e afetam mais de 80% da popula??o mundial. A maioria destas patologias ? tratada topicamente com medicamentos que n?o apresentam custo-efetividade satisfat?rio. O presente estudo tem como objetivo principal avaliar o potencial terap?utico do sesquiterpeno zerumbona, principal princ?pio ativo do ?leo essencial do Zingiber zerumbet (L.) Smith, contra infec??es cut?neas. Para a obten??o da Zerumbona, primeiramente o ?leo essencial foi submetido a hidrodestila??o e seguido pelo processo de recristaliza??o. Na sequ?ncia, an?lises cromatogr?ficas e espectrosc?picas foram realizadas para verifica??o do grau de pureza da Zerumbona obtida. A atividade antimicrobiana da Zerumbona contra os agentes microbianos Staphylococcus aureus, Staphylococcus epidermidis, Propionibacterium acnes e Candida albicans, foi verificada por meio dos m?todos de difus?o cavidade-placa e microdilui??o. Para determinar a atividade bactericida da Zerumbona em rela??o ao tempo, foi realizada a cin?tica de morte microbiana. O ?leo essencial obtido apresentou um alto teor de Zerumbona (87,95%), que ap?s passar pelo processo de recristaliza??o, o grau de pureza da subst?ncia aumentou para 98,79%, apresentando uma excelente atividade antimicrobiana contra S. aureus (CIM ?250?g/mL e CBM ?500?g/mL), P. acnes (CIM ?125?g/mL e CBM ?250?g/mL) e a levedura C. albicans (CIM ?100?g/mL e CFM ?200?g/mL). A subst?ncia natural apresentou efeito bactericida entre 6 e 12 horas para S. aureus e em 30 horas para P. acnes. A zerumbona foi capaz de inibir a forma??o de biofilme (S. aureus) a partir de ?500?g/mL. O potencial citot?xico e antioxidante foi avaliado atrav?s de ensaios in vitro, em cultura de c?lulas. A Zerumbona n?o apresentou efeitos citot?xicos em c?lulas eucari?ticas normais (VERO). A Capacidade Antioxidante Equivalente ao Trolox (TEAC) apresentou excelente atividade antioxidante (100?g/mL equivalente ? 0,65 nM/mL Trolox). Os resultados apresentados no referido trabalho, elucidam o potencial antimicrobinado da Zerumbona, frente aos microrganismos mais frequentes em infec??es cut?neas. Tais dados podem auxiliar no desenvolvimento de fitotrer?picos de uso t?pico, direcionados a infec??es de pele, a partir do princ?pio biotativo Zerumbona. Isto poder? servir de base para a gera??o de esquemas terap?uticos mais seguros, eficazes e de baixo custo.

Pathological skin changes such as impetigo, acne, erysipelas, cellulitis and boils are caused by microbial agents and affect more than 80% of the world?s population. Most of these pathologies are topically treated with drugs that do not have satisfactory cost-effectiveness. The present study has as main objective to evaluate the therapeutic potential of the sesquiterpene zerumbone the main active ingredient of the essential oil from Zingiber zerumbet (L.) Smith, against skin infections. For obtaining of zerumbona, the essential oil was submitted of hydrodistillation, will be subjected to…

Advisors/Committee Members: Orlandi, Patr?cia Puccinelli, 67812813215, http://lattes.cnpq.br/1887686774621627, Pontes, Gemilson Soares, http://lattes.cnpq.br/9081671233815990, Sales-Campos, Ceci, http://lattes.cnpq.br/9752987836124768, Lima J?nior, Raimundo Sousa, http://lattes.cnpq.br/2055426262014670, [email protected].

Subjects/Keywords: Infec??es cut?neas; ?leo essencial; Zerumbona; Amaz?nia; Antimicrobiano; CI?NCIAS BIOL?GICAS

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Pinheiro, C. D. F. (2017). Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas. (Masters Thesis). Universidade Federal do Amazonas. Retrieved from https://tede.ufam.edu.br/handle/tede/6940

Chicago Manual of Style (16th Edition):

Pinheiro, Carlos Danniel Freitas. “Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas.” 2017. Masters Thesis, Universidade Federal do Amazonas. Accessed February 16, 2020. https://tede.ufam.edu.br/handle/tede/6940.

MLA Handbook (7th Edition):

Pinheiro, Carlos Danniel Freitas. “Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas.” 2017. Web. 16 Feb 2020.

Vancouver:

Pinheiro CDF. Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas. [Internet] [Masters thesis]. Universidade Federal do Amazonas; 2017. [cited 2020 Feb 16]. Available from: https://tede.ufam.edu.br/handle/tede/6940.

Council of Science Editors:

Pinheiro CDF. Bioprospec??o do Sesquiterpeno zerumbona, para o tratamento de infec??es cut?neas. [Masters Thesis]. Universidade Federal do Amazonas; 2017. Available from: https://tede.ufam.edu.br/handle/tede/6940

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