subject:(acoustic radiation force impulse)

Rutgers University

1. Zhao, Xiaodong. Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation.

Degree: PhD, Mechanical and Aerospace Engineering, 2015, Rutgers University

URL: https://rucore.libraries.rutgers.edu/rutgers-lib/48743/

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Biomechanical imaging techniques based on acoustic radiation force (ARF) have been developed to characterize the viscoelasticity of soft tissue by measuring the motion induced with… (more)

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Biomechanical imaging techniques based on acoustic radiation force (ARF) have been developed to characterize the viscoelasticity of soft tissue by measuring the motion induced with ARF noninvasively. The unknown stress distribution in the region of excitation (ROE) limits an accurate inverse characterization of soft tissue viscoelasticity. Thus, many assumptions have been made for both qualitative and quantitative ARF imaging within the ROE. In this thesis, the finite element method is applied to study the dynamic behavior of soft tissue in ARF imaging within the ROE to investigate the assumptions that are made in these imaging methods and decide what factors affect the accuracy of these assumptions. To this end, the effects of global boundary conditions and local heterogeneity are investigated, and simplified quantitative inversion model is evaluated for their limitations in describing soft tissue dynamic behavior. In order to improve quantitative estimation within the ROE, an inverse finite element (FE) characterization procedure based on a Bayesian formulation is presented, which takes full advantage of the prior information of the imaging system that are discarded in the simplified inversion models. The Bayesian approach formulates the known model parameters of the FE models as probability distributions, and aims to estimate a reasonable quantification of the probability distributions of soft tissue mechanical properties rather than best-fit values from an optimization procedure, which are not a practical or a comprehensive description of the estimation in the presence of measurement noise and model parameter uncertainty. To make the Bayesian approach computationally feasible, the Gaussian Process metamodeling method is applied as a statistical approximation of the complex FE model. A comprehensive numerical study in ARF induced creep imaging shows that the Bayesian approach with FE model improves the estimation results even in the presence of large uncertainty levels of the model parameters and provides a potential to improve the ROE-response-based imaging methods where the unknown stress limits an accurate inverse FE characterization.

Advisors/Committee Members: Pelegri, Assimina A. (chair), Cuitino, Alberto (internal member), WENG, GEORGE (internal member), LaMattina, Bruce (outside member).

Subjects/Keywords: Acoustic radiation force impulse imaging; Viscoelasticity

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APA (6^th Edition):

Zhao, X. (2015). Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/48743/

Chicago Manual of Style (16^th Edition):

Zhao, Xiaodong. “Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation.” 2015. Doctoral Dissertation, Rutgers University. Accessed January 21, 2021. https://rucore.libraries.rutgers.edu/rutgers-lib/48743/.

MLA Handbook (7^th Edition):

Zhao, Xiaodong. “Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation.” 2015. Web. 21 Jan 2021.

Vancouver:

Zhao X. Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation. [Internet] [Doctoral dissertation]. Rutgers University; 2015. [cited 2021 Jan 21]. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/48743/.

Council of Science Editors:

Zhao X. Finite element characterization of soft tissue viscoelastic parameters in acoustic radiation force imaging within the region of excitation. [Doctoral Dissertation]. Rutgers University; 2015. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/48743/

2. Takashima, Makiko. Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価.

Degree: 博士（歯学）, 2016, Niigata University / 新潟大学

URL: http://hdl.handle.net/10191/42130

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学位の種類: 博士（歯学）. 報告番号: 甲第4144号. 学位記番号: 新大院博（歯）甲第342号. 学位授与年月日: 平成28年3月23日

We aimed to quantify masseter muscle stiffness in patients with masticatory myofascial pain. Masseter muscle stiffness was… (more)

Subjects/Keywords: masticatory muscle pain; temporomandibular disorders; stiffness; ultrasonography; myalgia; myofascial pain; elasticity imaging technique; characteristic pain intensity; acoustic radiation force impulse

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APA (6^th Edition):

Takashima, M. (2016). Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価. (Thesis). Niigata University / 新潟大学. Retrieved from http://hdl.handle.net/10191/42130

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

Chicago Manual of Style (16^th Edition):

Takashima, Makiko. “Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価.” 2016. Thesis, Niigata University / 新潟大学. Accessed January 21, 2021. http://hdl.handle.net/10191/42130.

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

MLA Handbook (7^th Edition):

Takashima, Makiko. “Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価.” 2016. Web. 21 Jan 2021.

Vancouver:

Takashima M. Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価. [Internet] [Thesis]. Niigata University / 新潟大学; 2016. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10191/42130.

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

Council of Science Editors:

Takashima M. Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography : せん断波エラストグラフィを用いた顎関節症患者の咬筋硬さの定量的評価. [Thesis]. Niigata University / 新潟大学; 2016. Available from: http://hdl.handle.net/10191/42130

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

Unitec New Zealand

3. Sharma, Avish. Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults.

Degree: 2016, Unitec New Zealand

URL: http://hdl.handle.net/10652/3506

► BACKGROUND: To date there are few studies of acceptable methodological quality investigating the reliability of elastography ultrasound use in the lower limb. The aim of… (more)

Subjects/Keywords: elasticity imaging technique; reliability; ultrasound elastography; quadriceps; acoustic radiation force impulse (ARFI) imaging; 110499 Complementary and Alternative Medicine not elsewhere classified

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APA (6^th Edition):

Sharma, A. (2016). Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults. (Thesis). Unitec New Zealand. Retrieved from http://hdl.handle.net/10652/3506

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

Chicago Manual of Style (16^th Edition):

Sharma, Avish. “Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults.” 2016. Thesis, Unitec New Zealand. Accessed January 21, 2021. http://hdl.handle.net/10652/3506.

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

MLA Handbook (7^th Edition):

Sharma, Avish. “Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults.” 2016. Web. 21 Jan 2021.

Vancouver:

Sharma A. Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults. [Internet] [Thesis]. Unitec New Zealand; 2016. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10652/3506.

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

Council of Science Editors:

Sharma A. Inter and intra-examiner reliability of ultrasound elastography for assessment of the anterior thigh in healthy adults. [Thesis]. Unitec New Zealand; 2016. Available from: http://hdl.handle.net/10652/3506

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

Michigan State University

4. Yang, Yiqun. Shear elasticity and shear viscosity imaging in soft tissue.

Degree: 2018, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:6990

► "In this thesis, a new approach is introduced that provides estimates of shear elasticity and shear viscosity using time-domain measurements of shear waves in viscoelastic… (more)

▼ "In this thesis, a new approach is introduced that provides estimates of shear elasticity and shear viscosity using time-domain measurements of shear waves in viscoelastic media. Simulations of shear wave particle displacements induced by an acoustic radiation force are accelerated significantly by a GPU. The acoustic radiation force is first calculated using the fast near field method (FNM) and the angular spectrum approach (ASA). The shear waves induced by the acoustic radiation force are then simulated in elastic and viscoelastic media using Green's functions. A parallel algorithm is developed to perform these calculations on a GPU, where the shear wave particle displacements at different observation points are calculated in parallel. The resulting speed increase enables rapid evaluation of shear waves at discrete points, in 2D planes, and for push beams with different spatial samplings and for different values of the f-number (f/#). The results of these simulations show that push beams with smaller f/# require a higher spatial sampling rate. The significant amount of acceleration achieved by this approach suggests that shear wave simulations with the Green's function approach are ideally suited for high-performance GPUs. Shear wave elasticity imaging determines the mechanical parameters of soft tissue by analyzing measured shear waves induced by an acoustic radiation force. To estimate the shear elasticity value, the widely used time-of-flight (TOF) method calculates the correlation between shear wave particle velocities at adjacent lateral observation points. Although this method provides accurate estimates of the shear elasticity in purely elastic media, our experience suggests that the TOF method consistently overestimates the shear elasticity values in viscoelastic media because the combined effects of diffraction, attenuation, and dispersion are not considered. To address this problem, we have developed an approach that directly accounts for all of these effects when estimating the shear elasticity. This new approach simulates shear wave particle velocities using a Green's function-based approach for the Voigt model, where the shear elasticity and viscosity values are estimated using an optimization-based approach that compares measured shear wave particle velocities with simulated shear wave particle velocities in the time-domain. The results are evaluated on a point-by-point basis to generate images. There is good agreement between the simulated and measured shear wave particle velocities, where the new approach yields much better images of the shear elasticity and shear viscosity than the TOF method. The new estimation approach is accelerated with an approximate viscoelastic Green's function model that is evaluated with shear wave data obtained from in vivo human livers. Instead of calculating shear waves with combinations of different shear elasticities and shear viscosities, shear waves are calculated with different shear elasticities on the GPU and then convolved with a viscous loss model, which… Advisors/Committee Members: McGough, Robert J, Baek, Seungik, Feeny, Brian F, Udpa, Lalita.

Subjects/Keywords: Viscoelasticity – Mathematical models; Shear waves – Simulation methods; Acoustic radiation force impulse imaging; Shear waves – Mathematical models; Biomedical engineering; Acoustics

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APA (6^th Edition):

Yang, Y. (2018). Shear elasticity and shear viscosity imaging in soft tissue. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:6990

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

Chicago Manual of Style (16^th Edition):

Yang, Yiqun. “Shear elasticity and shear viscosity imaging in soft tissue.” 2018. Thesis, Michigan State University. Accessed January 21, 2021. http://etd.lib.msu.edu/islandora/object/etd:6990.

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

MLA Handbook (7^th Edition):

Yang, Yiqun. “Shear elasticity and shear viscosity imaging in soft tissue.” 2018. Web. 21 Jan 2021.

Vancouver:

Yang Y. Shear elasticity and shear viscosity imaging in soft tissue. [Internet] [Thesis]. Michigan State University; 2018. [cited 2021 Jan 21]. Available from: http://etd.lib.msu.edu/islandora/object/etd:6990.

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

Council of Science Editors:

Yang Y. Shear elasticity and shear viscosity imaging in soft tissue. [Thesis]. Michigan State University; 2018. Available from: http://etd.lib.msu.edu/islandora/object/etd:6990

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

5. Tierney, Áine P. Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction.

Degree: 2012, University of Limerick

URL: http://hdl.handle.net/10344/2482

► Abdominal Aortic Aneurysms (AAAs) is a permanent and irreversible dilation of the infrarenal section of the aorta. AAA’s are generally asymptomatic, until rupture of the… (more)

▼ Abdominal Aortic Aneurysms (AAAs) is a permanent and irreversible dilation of the infrarenal section of the aorta. AAA’s are generally asymptomatic, until rupture of the AAA wall occurs. Rupture can lead to large abdominal bleeding and death within a short period of time. AAA formation affects the integrity of the aortic wall, leading to a decrease in compliance and tensile strength, increased wall stiffness and a progressive dilation of the wall. From a biomedical engineering perspective, rupture of an AAA occurs when, locally, the wall stress surpasses the strength of the wall. This suggests it is of importance to have wall property information and perform wall stress analysis which can assess the risk of rupture reliably. Noninvasive assessment of aneurysm wall properties would improve insight into the vascular changes, preceding rupture. This thesis aims to explore noninvasive methods of characterising aortic wall properties and the effectiveness of these techniques to aid in clinical assessment. In this study, the efficacy of acoustic radiation force impulse (ARFI) imaging for determination of aortic changes in vitro was reported. The study successfully developed an artificial aneurysm in excised tissue and the changes induced by aneurysm development were detected using ARFI. A feasibility case study demonstrated a method for estimation of in vivo tissue properties using ARFI and exhibited the viability of translation of this modality to AAA clinical use. Most preoperative imaging protocols use computerised tomography (CT) angiography with three dimensional (3D) reconstructions for sizing and planning. The resulting images are static images, despite the fact that the human aorta exists in a dynamic environment. The elastic properties of the aorta were examined to assess the changes in the dynamic environment using cardiac gated CT. Different regions of the aorta were shown to have different mechanical properties. High variation in mechanical behaviour was found to exist locally. A novel method which allowed these variances to be reflected in finite element reconstructions was established. This is believed to be an important step in the improvement and accuracy of finite element studies. The morphology and the regional variation in mechanical properties were both found to play a key role in accurate wall stress calculations. An index, described as Regional Prestress Rupture Index (RPRI), indicates that regional variations are important for accurate rupture prediction. The knowledge of regional distribution of mechanical behaviour and accurate wall dynamics has potential to be employed to improve the durability and long term clinical performance of stent-grafts used for treating AAA. A novel and elegant approach to compute the damage of the aorta using cardiac gated CT image data is also presented. This technique can also be applied to analyse image data of patients with cardiovascular disease and is not limited to the abdominal aorta. The study quantified tissue damage due to aneurysm formation. Due to the high… Advisors/Committee Members: McGloughlin, Timothy M., Callanan, Anthony.

Subjects/Keywords: adominal aortic aneurysms (AAAs); biomedical engineering; acoustic radiation force impulse

…aortic aneurysm tissue properties and rupture potential using acoustic radiation force impulse… …for the assessment of tissue elasticity is with acoustic radiation force impulse (ARFI… …Thesis xi Glossary of Terms xii Introduction 1 Chapter 1 Acoustic radiation force… …2002c). Acoustic radiation force is applied to absorbing or reflecting targets in the… …propagation path of an acoustic wave. Radiation force is a universal phenomenon in any wave motion…

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APA (6^th Edition):

Tierney, �. P. (2012). Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction. (Thesis). University of Limerick. Retrieved from http://hdl.handle.net/10344/2482

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

Chicago Manual of Style (16^th Edition):

Tierney, Áine P. “Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction.” 2012. Thesis, University of Limerick. Accessed January 21, 2021. http://hdl.handle.net/10344/2482.

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

MLA Handbook (7^th Edition):

Tierney, Áine P. “Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction.” 2012. Web. 21 Jan 2021.

Vancouver:

Tierney �P. Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction. [Internet] [Thesis]. University of Limerick; 2012. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10344/2482.

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

Council of Science Editors:

Tierney �P. Noninvasive methods of characterising local regional variations in aortic tissue to advance aneurysm rupture risk prediction. [Thesis]. University of Limerick; 2012. Available from: http://hdl.handle.net/10344/2482

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

6. Eyerly, Stephanie Ann. Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures .

Degree: 2013, Duke University

URL: http://hdl.handle.net/10161/8200

► This dissertation investigates the use of intraprocedure acoustic radiation force impulse (ARFI) imaging for visualization of radiofrequency ablation (RFA) lesions during cardiac transcatheter ablation… (more)

▼ This dissertation investigates the use of intraprocedure acoustic radiation force impulse (ARFI) imaging for visualization of radiofrequency ablation (RFA) lesions during cardiac transcatheter ablation (TCA) procedures. Tens of thousands of TCA procedures are performed annually to treat atrial fibrillation (AF) and other cardiac arrhythmias. Despite the use of sophisticated electroanatomical mapping (EAM) techniques to validate the modification of the electrical substrate, post-procedure arrhythmia recurrence is common due to incomplete lesion delivery and electrical conduction through lesion line discontinuities. The clinical demand for an imaging modality that can visually confirm the presence and completeness of RFA lesion lines motivated this research. ARFI imaging is an ultrasound-based technique that transmits radiation force impulses to locally displace tissue and uses the tissue deformation response to generate images of relative tissue stiffness. RF-induced heating causes irreversible tissue necrosis and contractile protein denaturation that increases the stiffness of the ablated region. Preliminary in vitro and in vivo feasibility studies determined RF ablated myocardium appears stiffer in ARFI images. This thesis describes results for ARFI imaging of RFA lesions for three research milestones: 1) an in vivo experimental verification model, 2) a clinically translative animal study, and 3) a preliminary clinical feasibility trial in human patients. In all studies, 2-D ARFI images were acquired in normal sinus rhythm and during diastole to maximize the stiffness contrast between the ablated and unablated myocardium and to minimize the bulk cardiac motion during the acquisition time. The first in vivo experiment confirmed there was a significant decrease in the measured ARFI-induced displacement at ablation sites during and after focal RFA; the displacements in the lesion border zone and the detected lesion area stabilized over the first several minutes post-ablation. The implications of these results for ARFI imaging methods and the clinical relevance of the findings are discussed. The second and third research chapters of this thesis describe the system integration and implementation of a multi-modality intracardiac ARFI imaging-EAM system for intraprocedure lesion evaluation. EAM was used to guide the 2-D ARFI imaging plane to targeted ablation sites in the canine right atrium (RA); the presence of EAM lesions markers and conduction disturbances in the local activation time (LAT) maps were used to find the sensitivity and specificity of predicting the presence of RFA lesion with ARFI imaging. The contrast and contrast-to-noise ratio between RFA lesion and unablated myocardium were calculated for ARFI and conventional ICE images. The opportunities and potential developments for clinical translation are discussed. The last research chapter in this thesis describes a feasibility study of intracardiac ARFI imaging of RFA lesions in clinical patients. ARFI images of… Advisors/Committee Members: Wolf, Patrick D (advisor).

Subjects/Keywords: Biomedical engineering; Acoustic Radiation Force Impulse Imaging; Cardiac Radiofrequency Ablation

…2.4 Acoustic Radiation Force Impulse (ARFI) Imaging… …dimensional 3-D three-dimensional AF atrial fibrillation ARFI acoustic radiation force impulse… …20 2.4.1 Acoustic Radiation Force… …units J/mol·K A frequency factor, units 1/s F acoustic radiation force, units kg/s2·cm2… …radiation force impulse (ARFI) imaging is an ultrasound-based elasticity imaging…

10 more images…

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APA (6^th Edition):

Eyerly, S. A. (2013). Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/8200

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

Chicago Manual of Style (16^th Edition):

Eyerly, Stephanie Ann. “Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures .” 2013. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/8200.

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

MLA Handbook (7^th Edition):

Eyerly, Stephanie Ann. “Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures .” 2013. Web. 21 Jan 2021.

Vancouver:

Eyerly SA. Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures . [Internet] [Thesis]. Duke University; 2013. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/8200.

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

Council of Science Editors:

Eyerly SA. Acoustic Radiation Force Impulse Imaging of Radiofrequency Ablation Lesions for Cardiac Ablation Procedures . [Thesis]. Duke University; 2013. Available from: http://hdl.handle.net/10161/8200

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

Kyoto University

7. Yoshino, Kenji. The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation .

Degree: 2019, Kyoto University

URL: http://hdl.handle.net/2433/242376

Subjects/Keywords: acoustic radiation force impulse; biopsy; fibrosis; liver stiffness measurement; liver transplantation

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APA (6^th Edition):

Yoshino, K. (2019). The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/242376

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

Chicago Manual of Style (16^th Edition):

Yoshino, Kenji. “The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation .” 2019. Thesis, Kyoto University. Accessed January 21, 2021. http://hdl.handle.net/2433/242376.

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

MLA Handbook (7^th Edition):

Yoshino, Kenji. “The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation .” 2019. Web. 21 Jan 2021.

Vancouver:

Yoshino K. The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation . [Internet] [Thesis]. Kyoto University; 2019. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/2433/242376.

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

Council of Science Editors:

Yoshino K. The efficiency of acoustic radiation force impulse imaging for the staging of graft fibrosis after liver transplantation . [Thesis]. Kyoto University; 2019. Available from: http://hdl.handle.net/2433/242376

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

Universiteit Utrecht

8. Carvajal Gallardo, E.N. MR methods for imaging of acoustic radiation force in tissue.

Degree: 2011, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/214980

► In this thesis the theory behind acoustic radiation force and the theory of elasticity are presented, which are used to characterize tissue displacements due to… (more)

Subjects/Keywords: acoustic radiation force; radiation force; MRI; MR; MRE; MR-ARFI; elastography

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APA (6^th Edition):

Carvajal Gallardo, E. N. (2011). MR methods for imaging of acoustic radiation force in tissue. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/214980

Chicago Manual of Style (16^th Edition):

Carvajal Gallardo, E N. “MR methods for imaging of acoustic radiation force in tissue.” 2011. Masters Thesis, Universiteit Utrecht. Accessed January 21, 2021. http://dspace.library.uu.nl:8080/handle/1874/214980.

MLA Handbook (7^th Edition):

Carvajal Gallardo, E N. “MR methods for imaging of acoustic radiation force in tissue.” 2011. Web. 21 Jan 2021.

Vancouver:

Carvajal Gallardo EN. MR methods for imaging of acoustic radiation force in tissue. [Internet] [Masters thesis]. Universiteit Utrecht; 2011. [cited 2021 Jan 21]. Available from: http://dspace.library.uu.nl:8080/handle/1874/214980.

Council of Science Editors:

Carvajal Gallardo EN. MR methods for imaging of acoustic radiation force in tissue. [Masters Thesis]. Universiteit Utrecht; 2011. Available from: http://dspace.library.uu.nl:8080/handle/1874/214980

9. Andrade, Marco Aurélio Brizzotti. Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias.

Degree: PhD, Engenharia de Controle e Automação Mecânica, 2010, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-164959/ ;

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O objetivo deste trabalho é estudar o fenômeno da força de radiação acústica produzida por ondas progressivas e estacionárias. Neste trabalho o estudo da força… (more)

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O objetivo deste trabalho é estudar o fenômeno da força de radiação acústica produzida por ondas progressivas e estacionárias. Neste trabalho o estudo da força produzida por ondas estacionárias é aplicado na análise de um levitador acústico e o estudo da força de radiação acústica por ondas progressivas é feito visando a futura construção de um separador acústico. Neste trabalho é utilizado o método dos elementos finitos para simular o comportamento de um levitador acústico. Primeiramente, é feita a simulação de um levitador acústico que consiste de um transdutor de Langevin com uma face de emissão plana que opera na freqüência de aproximadamente 20 kHz e um refletor plano. O método dos elementos finitos é utilizado para determinar o deslocamento da face do transdutor e o potencial acústico que atua numa esfera pequena. O deslocamento da face do transdutor obtido numericamente é comparado com o medido experimentalmente por um vibrômetro de fibra ótica e o potencial acústico determinado pelo método dos elementos é verificado experimentalmente colocando pequenas esferas de isopor no levitador. Depois de verificar o modelo numérico, o método dos elementos finitos é utilizado na otimização de um levitador acústico composto de um refletor côncavo e um transdutor com face de emissão côncava. Os resultados numéricos mostram que a força de radiação acústica no novo levitador é aumentada em 604 vezes quando comparada com o levitador composto de um transdutor com face plana e refletor plano. Este trabalho também apresenta um modelo numérico para determinar a trajetória de partículas esféricas na presença de uma onda de ultra-som progressiva. O modelo assume que as seguintes forças atuam na partícula: gravidade, empuxo, forças viscosas e força de radiação acústica devido a uma onda progressiva. Com o objetivo de não restringir o tamanho das partículas que podem ser utilizadas no modelo é empregada uma equação empírica do coeficiente de arrasto, válida para uma grande faixa de número de Reynolds. O modelo proposto requer a distribuição de pressão gerada pelo transdutor de ultra-som. A distribuição de pressão é medida experimentalmente utilizando um hidrofone calibrado. A verificação do modelo é feita soltando-se pequenas esferas de vidro (com diâmetros da ordem de 500 m) em frente a um transdutor de ultra-som de 1 MHz e 35 mm de diâmetro.

The objective of this work is to study the acoustic radiation force produced by progressive and standing waves. In this work, the studies related to the acoustic radiation force generated by ultrasonic standing waves are applied in the analysis of an acoustic levitator and the studies involving the acoustic radiation force generated by progressive waves are conducted aiming the design of acoustic separators. In this work, the finite element method is used to simulate an acoustic levitator. First, an acoustic levitator consisting of a 20 kHz Langevin ultrasonic transducer with a plane radiating surface and a plane reflector is simulated by the finite element method. The finite element…

Advisors/Committee Members: Adamowski, Júlio Cezar.

Subjects/Keywords: Acoustic levitation; Acoustic radiation force; Acústica; Método dos elementos finitos; Ondas; Ultrasound

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APA (6^th Edition):

Andrade, M. A. B. (2010). Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-164959/ ;

Chicago Manual of Style (16^th Edition):

Andrade, Marco Aurélio Brizzotti. “Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias.” 2010. Doctoral Dissertation, University of São Paulo. Accessed January 21, 2021. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-164959/ ;.

MLA Handbook (7^th Edition):

Andrade, Marco Aurélio Brizzotti. “Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias.” 2010. Web. 21 Jan 2021.

Vancouver:

Andrade MAB. Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias. [Internet] [Doctoral dissertation]. University of São Paulo; 2010. [cited 2021 Jan 21]. Available from: http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-164959/ ;.

Council of Science Editors:

Andrade MAB. Estudo da força de radiação acústica em partículas produzida por ondas progressivas e estacionárias. [Doctoral Dissertation]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/3/3152/tde-11082010-164959/ ;

University of South Florida

10. Asoda, Shivaraman. Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator.

Degree: 2018, University of South Florida

URL: https://scholarcommons.usf.edu/etd/8103

► Standing surface acoustic waves (SSAW) have been widely used for sorting of cells and particles. However, the major challenges faced with the acoustic driven separation… (more)

Subjects/Keywords: Acoustic Radiation Force; Microfluidics; Separation Efficiency; Standing Surface Acoustic Wave; Mechanical Engineering

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APA (6^th Edition):

Asoda, S. (2018). Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/8103

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

Chicago Manual of Style (16^th Edition):

Asoda, Shivaraman. “Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator.” 2018. Thesis, University of South Florida. Accessed January 21, 2021. https://scholarcommons.usf.edu/etd/8103.

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

MLA Handbook (7^th Edition):

Asoda, Shivaraman. “Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator.” 2018. Web. 21 Jan 2021.

Vancouver:

Asoda S. Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator. [Internet] [Thesis]. University of South Florida; 2018. [cited 2021 Jan 21]. Available from: https://scholarcommons.usf.edu/etd/8103.

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

Council of Science Editors:

Asoda S. Simulation and Optimization of a Sheathless Size-Based Acoustic Particle Separator. [Thesis]. University of South Florida; 2018. Available from: https://scholarcommons.usf.edu/etd/8103

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

11. Kakkad, Vaibhav. Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods .

Degree: 2018, Duke University

URL: http://hdl.handle.net/10161/18225

► Heart failure is one of the most common cardiac disorders and is projected to increase in prevalence over the next few decades. It can… (more)

▼ Heart failure is one of the most common cardiac disorders and is projected to increase in prevalence over the next few decades. It can arise from a wide variety of root causes such as coronary artery disease, hypertension, cardiomyopathy, or cardiotoxicity and can manifest as systolic and/or diastolic dysfunction. Traditionally, its diagnosis has been based on monitoring qualitative changes in cardiac structure, such as chamber geometry and wall motion patterns, or quantitative changes in indices of cardiac function, such as the blood flow velocities and ventricular ejection fraction. These parameters are assessed in clinical settings using medical imaging modalities like ultrasound and magnetic resonance imaging. Recent research into cardiac pathophysiology has indicated that the progression of cardiac disease is often accompanied by changes in the mechanical properties of cardiac muscle. Interrogation of these changes could be used to gain useful diagnostic insight into the etiology of heart failure. Acoustic radiation force (ARF)-based techniques, such as acoustic radiation force impulse (ARFI) imaging and shear wave elasticity imaging (SWEI), provide the means to measure mechanical properties of soft tissues using ultrasound. They operate on the principle that ultrasound can be used to remotely generate as well as track micron-level vibrations in the body and thus derive mechanical properties such as tissue stiffness. ARFI and SWEI have previously been shown to capture dynamic changes in myocardial stiffness in Langendorff set-ups, open-chest experiments, and intracardiac settings. This dissertation explores the challenges and opportunities of implementing acoustic radiation force-based methods for noninvasive applications via transthoracic imaging windows. Transthoracic imaging of the heart using ultrasound can be challenging for a number of reasons. The two main sources of signal degradation that were hypothesized to impact ARFI and SWEI in this environment are acoustic clutter and intrinsic tissue motion. Acoustic clutter refers to incorrectly localized echoes which lead to the degradation of target conspicuity, border delineation, and image quality. Intrinsic tissue motion, on the other hand, impedes the ability to accurately measure the ARF-induced motion and consequently affects the estimation of tissue stiffness. The work presented herein focuses on quantifying the level of both sources of signal degradation under it{in vivo} imaging conditions and evaluating the effectiveness of strategies to minimize their impact. Lastly, the feasibility of tracking dynamic myocardial stiffness through the cardiac cycle via transthoracic imaging windows on human volunteers was investigated. Harmonic imaging is often used to suppress acoustic clutter in clinical settings. Clutter levels are also closely tied to the choice of beamforming configuration used. Quantifying the impact of harmonic imaging and transmit beamforming (focused versus plane wave) on acoustic clutter, under it{in vivo}… Advisors/Committee Members: Trahey, Gregg (advisor).

Subjects/Keywords: Medical imaging; Acoustic Clutter; Acoustic Radiation Force; Cardiac Motion; Myocardial Stiffness; Transthoracic Echocardiography; Ultrasound Imaging

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

APA (6^th Edition):

Kakkad, V. (2018). Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/18225

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

Chicago Manual of Style (16^th Edition):

Kakkad, Vaibhav. “Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods .” 2018. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/18225.

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

MLA Handbook (7^th Edition):

Kakkad, Vaibhav. “Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods .” 2018. Web. 21 Jan 2021.

Vancouver:

Kakkad V. Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods . [Internet] [Thesis]. Duke University; 2018. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/18225.

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

Council of Science Editors:

Kakkad V. Transthoracic Measurement of Dynamic Myocardial Stiffness using Acoustic Radiation Force-Based Ultrasound Methods . [Thesis]. Duke University; 2018. Available from: http://hdl.handle.net/10161/18225

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

Universiteit Utrecht

12. Wetering, M.M.C. Ultrasound mediated local drug delivery.

Degree: 2010, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/186882

► In the field of drug delivery, it has great importance to have sufficient drug accumulation at the diseased site. To obtain this goal it is… (more)

Subjects/Keywords: Drug delivery; Ultrasound; Drug carriers; Hyperthermia; Cavitation; Acoustic Radiation Force

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

APA (6^th Edition):

Wetering, M. M. C. (2010). Ultrasound mediated local drug delivery. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/186882

Chicago Manual of Style (16^th Edition):

Wetering, M M C. “Ultrasound mediated local drug delivery.” 2010. Masters Thesis, Universiteit Utrecht. Accessed January 21, 2021. http://dspace.library.uu.nl:8080/handle/1874/186882.

MLA Handbook (7^th Edition):

Wetering, M M C. “Ultrasound mediated local drug delivery.” 2010. Web. 21 Jan 2021.

Vancouver:

Wetering MMC. Ultrasound mediated local drug delivery. [Internet] [Masters thesis]. Universiteit Utrecht; 2010. [cited 2021 Jan 21]. Available from: http://dspace.library.uu.nl:8080/handle/1874/186882.

Council of Science Editors:

Wetering MMC. Ultrasound mediated local drug delivery. [Masters Thesis]. Universiteit Utrecht; 2010. Available from: http://dspace.library.uu.nl:8080/handle/1874/186882

University of Utah

13. De bever, Joshua Thomas. Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies.

Degree: PhD, School of Computing, 2015, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3826/rec/145

► Focused ultrasound (FUS) is a promising noninvasive and radiation-free cancer therapy that selectively delivers high-intensity acoustic energy to a small target volume. This dissertation presents… (more)

▼ Focused ultrasound (FUS) is a promising noninvasive and radiation-free cancer therapy that selectively delivers high-intensity acoustic energy to a small target volume. This dissertation presents original research that improves the speed, safety, and efficacy of FUS therapies under magnetic resonance imaging (MRI) guidance. First, a new adaptive model-predictive controller is presented that leverages the ability of MRI to measure temperature inside the patient at near real-time speeds. The controller uses MR temperature feedback to dynamically derive and update a patient-specific thermal model, and optimizes the treatment based on the model's predictions. Treatment safety is a key element of the controller's design, and it can actively protect healthy tissue from unwanted damage. In vivo and simulation studies indicate the controller can safeguard healthy tissue and accelerate treatments by as much as 50%. Significant tradeoffs exist between treatment speed, and safety, which makes a real-time controller absolutely necessary for carrying out efficient, effective, and safe treatments while also highlighting the importance of continued research into optimal treatment planning. Next, two new methods for performing 3D MR acoustic radiation force imaging (MR-ARFI) are presented. Both techniques measure the tissue displacement induced by short bursts of focused ultrasound, and provide a safe way to visualize the ultrasound beam's location. In some scenarios, ARFI is a necessity for proper targeting since traditional MR thermometry cannot measure temperature in fat. The first technique for performing 3D ARFI introduces a novel unbalanced bipolar motion encoding gradient. The results demonstrate that this technique is safe, and that 3D displacement maps can be attained time-efficiently even in organs that contain fat, such as breast. The second technique measures 3D ARFI simultaneously with temperature monitoring. This method uses a multi-contrast gradient recalled echo sequence which makes multiple readings of the data without increasing scan time. This improves the signal to noise ratio and makes it possible to separate the effects of tissue heating vs displacement. Both of the 3D MR-ARFI techniques complement the presented controllersince proper positioning of the focal spot is critical to achieving fast and safe treatments.

Subjects/Keywords: Acoustic Radiation Force Imaging; Focused Ultrasound; Model-Predictive Control; MRI

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

APA (6^th Edition):

De bever, J. T. (2015). Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3826/rec/145

Chicago Manual of Style (16^th Edition):

De bever, Joshua Thomas. “Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies.” 2015. Doctoral Dissertation, University of Utah. Accessed January 21, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3826/rec/145.

MLA Handbook (7^th Edition):

De bever, Joshua Thomas. “Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies.” 2015. Web. 21 Jan 2021.

Vancouver:

De bever JT. Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies. [Internet] [Doctoral dissertation]. University of Utah; 2015. [cited 2021 Jan 21]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3826/rec/145.

Council of Science Editors:

De bever JT. Adaptive model-predictive control and 3d acoustic radiation force imaging for the improvement of magnetic resonance-guided focused ultrasound therapies. [Doctoral Dissertation]. University of Utah; 2015. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3826/rec/145

University of Manchester

14. Saunders, Catherine. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.

Degree: PhD, 2014, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/asymptotic-methods-applied-to-problems-of-steadystreaming-flows-and-acoustic-radiation-forces(7c4856bd-5d9d-44b5-bac7-d2aed745f258).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617999

► Small-amplitude, high-frequency (ultrasound) forcing of fluid/particle systems is being used in a number of applications associated with non-destructive fluid mixing and the movement/manipulation of particles… (more)

▼ Small-amplitude, high-frequency (ultrasound) forcing of fluid/particle systems is being used in a number of applications associated with non-destructive fluid mixing and the movement/manipulation of particles in suspension. Of most importance in this context are the second-order, steady, effects arising from the nonlinear interaction of a leading-order oscillatory field with itself. In this thesis we consider some of these steady effects in both incompressible and compressible fluids. We first consider the axisymmetric steady streaming generated in an incompressible, viscous fluid contained between two (radially) infinite parallel plates, each oscillating in a direction normal to its own plane. In the limit of small-amplitude, high-frequency oscillations, we show that the steady-streaming flow in the fluid bulk is driven by thin streaming sublayers at the plates, at which the normal velocity is zero and the radial velocity varies linearly with distance from the axis of rotational symmetry. Effectively, in the bulk flow, the bounding plates appear as (no-slip) impermeable walls that stretch radially. This bulk-flow problem is extended to allow for the analogous steady flow of two immiscible, incompressible, viscous fluids, each undergoing a radial-stretching motion appropriate to high-frequency steady streaming. For a flat interface between the fluids, a self-similar solution reduces the Navier – Stokes equations to a nonlinear boundary-value problem, the solution of which exhibits an interesting structure in the limit of large Reynolds number. In this limit, solutions can be found using matched asymptotic expansions, but the location of the interface between the fluids can only be determined if terms that are exponentially small in the Reynolds number are included. It is shown that for fluids of almost-equal densities, exponentially-small differences can have a leading-order effect on the observed flow. The second part of the thesis is concerned with the (steady) acoustic radiation force on a rigid sphere submerged in a compressible, inviscid fluid, when the wavelength of the incident acoustic field is large compared to the radius of the sphere. In this limit, a matched asymptotic expansion method is used to derive an expression for the acoustic radiation force, on both fixed and free rigid spheres, due to a range of incident fields. For incident acoustic fields that are appropriate to planar and circular waveguides/channels, expressions are derived for the scattered field and the radiation force on a rigid sphere in the long-wavelength limit. Fixed and free spheres located both on and off the axis of symmetry of these incident fields are considered. This is an extension to the current literature, in which numerical methods are used to examine the scattering from spheres in an off-axis position, and problems are restricted to the consideration of fixed spheres only. It is shown that there are stable and unstable positions within the waveguide where any off-axis acoustic radiation force vanishes, leaving only an…

Subjects/Keywords: 530.15; Asymptotic methods; Steady streaming; Acoustic radiation force

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

APA (6^th Edition):

Saunders, C. (2014). Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/asymptotic-methods-applied-to-problems-of-steadystreaming-flows-and-acoustic-radiation-forces(7c4856bd-5d9d-44b5-bac7-d2aed745f258).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617999

Chicago Manual of Style (16^th Edition):

Saunders, Catherine. “Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.” 2014. Doctoral Dissertation, University of Manchester. Accessed January 21, 2021. https://www.research.manchester.ac.uk/portal/en/theses/asymptotic-methods-applied-to-problems-of-steadystreaming-flows-and-acoustic-radiation-forces(7c4856bd-5d9d-44b5-bac7-d2aed745f258).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617999.

MLA Handbook (7^th Edition):

Saunders, Catherine. “Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.” 2014. Web. 21 Jan 2021.

Vancouver:

Saunders C. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2021 Jan 21]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/asymptotic-methods-applied-to-problems-of-steadystreaming-flows-and-acoustic-radiation-forces(7c4856bd-5d9d-44b5-bac7-d2aed745f258).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617999.

Council of Science Editors:

Saunders C. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. [Doctoral Dissertation]. University of Manchester; 2014. Available from: https://www.research.manchester.ac.uk/portal/en/theses/asymptotic-methods-applied-to-problems-of-steadystreaming-flows-and-acoustic-radiation-forces(7c4856bd-5d9d-44b5-bac7-d2aed745f258).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617999

15. Bing, Kristin Frinkley. The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System .

Degree: 2008, Duke University

URL: http://hdl.handle.net/10161/904

► Ultrasound can be used for a variety of therapeutic purposes. High-intensity focused ultrasound (HIFU) has progressed over the past decade to become a viable… (more)

▼ Ultrasound can be used for a variety of therapeutic purposes. High-intensity focused ultrasound (HIFU) has progressed over the past decade to become a viable therapeutic method and is valuable as a non-invasive alternative to many surgical procedures. Ultrasonic thermal therapies can also be used to release thermally sensitive liposomes encapsulating chemotherapeutic drugs. In the brain, the permeability of the blood-brain barrier to drugs, antibodies, and gene transfer can be increased with a mechanical mechanism using ultrasound and contrast agent. The work presented in this dissertation tests the hypothesis that a diagnostic system can be used for combined imaging and therapeutic applications. In order to evaluate the effectiveness of a diagnostic system for use in therapeutic applications, a set of non-destructive tests is developed that can predict the potential for high acoustic output. A rigorous, nondestructive testing regimen for standard, diagnostic transducers to evaluate their potential for therapeutic use is formulated. Based on this work, transducer heating is identified as the largest challenge. The design and evaluation of several custom diagnostic transducers with various modifications to reduce internal heating are described. These transducers are compared with diagnostic controls using image contrast, face heating, hydrophone, and ARFI displacement measurements. From these results, we conclude that the most promising design is a passively and actively cooled, PZT-4 multilayer composite transducer, while the acoustically lossless lens and capactive micro-machined transducers evaluated herein are determined to be ineffective. Three therapeutic applications are evaluated for the combined system. Image-guided spot ablations, such as in the treatment of early stage liver cancers, could not be successfully performed; however, the additional acoustic output requirements are determined to be on the order of 2.4 times those that can be currently produced without transducer damage in a clinically relevant amount of time (10-20 seconds per spot). The potential of a diagnostic system for a hyperthermia application is shown by producing temperatures for the duration necessary to release chemotherapeutic agents from thermally-activated liposomes without damage to the transducer. Finally, a mechanically-based therapeutic method for opening the BBB with ultrasonic contrast agent and specialized sonication regimes under ultrasonic B-mode guidance is demonstrated. These studies indicate that a diagnostic system is capable of both moderate thermal and mechanical therapeutic applications under co-registered image-guidance. Advisors/Committee Members: Nightingale, Kathryn R (advisor).

Subjects/Keywords: Engineering, Biomedical; diagnostic ultrasound; high; intensity focused ultrasound; blood; brain barrier; liposome; acoustic output; acoustic radiation force impulse imaging

…Doppler), 70 µs (Acoustic Radiation Force Impulse Imaging), and 20 ms on BBB… …conventional B-mode ultrasound and acoustic radiation force impulse (ARFI) visualization of… …focused, impulse acoustic radiation force excitations and, thus, visualizes structures with… …elastographic techniques, such as acoustic radiation force impulse (ARFI) imaging. The… …3.4 Acoustic Radiation Force . . . . . . . . . . . . . . . . . . . . . 54 Golden Spike…

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APA (6^th Edition):

Bing, K. F. (2008). The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/904

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

Chicago Manual of Style (16^th Edition):

Bing, Kristin Frinkley. “The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System .” 2008. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/904.

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

MLA Handbook (7^th Edition):

Bing, Kristin Frinkley. “The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System .” 2008. Web. 21 Jan 2021.

Vancouver:

Bing KF. The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System . [Internet] [Thesis]. Duke University; 2008. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/904.

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

Council of Science Editors:

Bing KF. The Potential for Ultrasonic Image-Guided Therapy Using a Diagnostic System . [Thesis]. Duke University; 2008. Available from: http://hdl.handle.net/10161/904

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

University of South Florida

16. Jo, Myeong Chan. An Acoustic-based Microfluidic Platform for Active Separation and Mixing.

Degree: 2013, University of South Florida

URL: https://scholarcommons.usf.edu/etd/4697

► Particle separation is of great interest to many biological and biomedical applications. Flow-based methods have been used to sort particles and cells. However, the main… (more)

▼ Particle separation is of great interest to many biological and biomedical applications. Flow-based methods have been used to sort particles and cells. However, the main challenge with flow based particle separation systems is the need for a sheath flow for successful operation. Existence of the sheath liquid dilutes the analyte, necessitates precise flow control between sample and sheath flow, requires a complicated design to create sheath flow and separation efficiency depends on the sheath liquid composition. In addition, current gold standard active separation techniques are only capable of separation based on particle size; hence, separation cannot be achieved for same-size particles with different densities. In this dissertation, a sheathless acoustic-based microfluidic platform using surface acoustic wave for not only size-dependent but also density-dependent particle separation has been investigated. In this platform, two different functions were incorporated within a single microfluidic channel with varying the number of pressure node and position. The first function was to align particles on the center of the microfluidic channel without adding any external sheath flow. The second function was to separate particles according to their size or density. Two different size-pairs of polystyrene particles with different diameters (3 µm and 10 µm for general size-resolution, 3 µm and 5 µm for higher size-resolution) were successfully separated. Also, the separation of two 10 µm diameter, different-density particle streams (polystyrene: 1.05 g/cm3, melamine: 1.71 g/cm3) was successfully demonstrated. The effects of the input power, the flow rate, and particle concentration on the separation efficiency were investigated. A range of high separation efficiencies with 94.8-100 % for size-based separation and 87.2 - 98.9 % for density-based separation were accomplished. In this dissertation, an acoustic-based microfluidic platform using dual acoustic streaming for active mixing has also been investigated. The rapid and high efficiency mixing of a fluorescent dye solution and deionized water in a microfluidic channel was demonstrated with single acoustic excitation by one interdigital transducer (IDT) as well as dual excitation by two IDTs. The mixing efficiencies were investigated as a function of applied voltage and flow rates. The results indicate that with the same operation parameters, the mixing efficiency with dual-IDT design increased to 96.7 % from 69.8 % achievable with the traditional single-IDT design. The effect of aperture length of the IDT on mixing efficiency was also investigated. Additionally, the effects of the polydimethylsiloxane (PDMS) channel wall thickness on the insertion loss and the particle migration to the pressure node due to acoustic radiation forces induced by SAW have been investigated. The results indicate that as the PDMS channel wall thickness decreased, the SAW insertion loss is reduced as well as the velocity of the particle migration due to acoustic forces increased significantly.…

Subjects/Keywords: Acoustic radiation force; Acoustic streaming; Interdigital transducer; Microfluidics; Polydimethylsiloxane (PDMS); Surface acoustic wave; Biomedical Engineering and Bioengineering; Mechanical Engineering

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APA (6^th Edition):

Jo, M. C. (2013). An Acoustic-based Microfluidic Platform for Active Separation and Mixing. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/4697

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

Chicago Manual of Style (16^th Edition):

Jo, Myeong Chan. “An Acoustic-based Microfluidic Platform for Active Separation and Mixing.” 2013. Thesis, University of South Florida. Accessed January 21, 2021. https://scholarcommons.usf.edu/etd/4697.

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

MLA Handbook (7^th Edition):

Jo, Myeong Chan. “An Acoustic-based Microfluidic Platform for Active Separation and Mixing.” 2013. Web. 21 Jan 2021.

Vancouver:

Jo MC. An Acoustic-based Microfluidic Platform for Active Separation and Mixing. [Internet] [Thesis]. University of South Florida; 2013. [cited 2021 Jan 21]. Available from: https://scholarcommons.usf.edu/etd/4697.

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

Council of Science Editors:

Jo MC. An Acoustic-based Microfluidic Platform for Active Separation and Mixing. [Thesis]. University of South Florida; 2013. Available from: https://scholarcommons.usf.edu/etd/4697

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

University of Rochester

17. Langdon, Jonathan H. Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues.

Degree: PhD, 2016, University of Rochester

URL: http://hdl.handle.net/1802/30602

► In response to chronic inflammation, many tissues undergo a transformation known as fibrosis that results in increased stiffness of the tissue. The parenchyma of the… (more)

Subjects/Keywords: Acoustic radiation force; Computational methods; Elastography; Finite difference time domain; Shear wave imaging; Viscoelasticity

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APA (6^th Edition):

Langdon, J. H. (2016). Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/30602

Chicago Manual of Style (16^th Edition):

Langdon, Jonathan H. “Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues.” 2016. Doctoral Dissertation, University of Rochester. Accessed January 21, 2021. http://hdl.handle.net/1802/30602.

MLA Handbook (7^th Edition):

Langdon, Jonathan H. “Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues.” 2016. Web. 21 Jan 2021.

Vancouver:

Langdon JH. Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues. [Internet] [Doctoral dissertation]. University of Rochester; 2016. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/1802/30602.

Council of Science Editors:

Langdon JH. Development of single track location shear wave viscoelasticity imaging for real-time characterization of biological tissues. [Doctoral Dissertation]. University of Rochester; 2016. Available from: http://hdl.handle.net/1802/30602

18. Hollender, Peter J. Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods .

Degree: 2014, Duke University

URL: http://hdl.handle.net/10161/9388

► Implemented on an intracardiac echocardiography transducer, acoustic radiation force methods may provide a useful means of characterizing the heart's elastic properties. Elasticity imaging may… (more)

▼ Implemented on an intracardiac echocardiography transducer, acoustic radiation force methods may provide a useful means of characterizing the heart's elastic properties. Elasticity imaging may be of benefit for diagnosis and characterization of infarction and heart failure, as well as for guidance of ablation therapy for the treatment of arrhythmias. This thesis tests the hypothesis that with appropriately designed imaging sequences, intracardiac acoustic radiation force impulse (ARFI) imaging and shear wave elasticity imaging (SWEI) are viable tools for quantification of myocardial elasticity, both temporally and spatially. Multiple track location SWEI (MTL-SWEI) is used to show that, in healthy in vivo porcine ventricles, shear wave speeds follow the elasticity changes with contraction and relaxation of the myocardium, varying between 0.9 and 2.2 m/s in diastole and 2.6 and 5.1 m/s in systole. Infarcted tissue is less contractile following infarction, though not unilaterally stiffer. Single-track-location SWEI (STL-SWEI) is proven to provide suppression of speckle noise and enable improved resolution of structures smaller than 2 mm in diameter compared to ARFI and MTL-SWEI. Contrast to noise ratio and lateral edge resolution are shown to vary with selection of time step for ARFI and arrival time regression filter size for STL-SWEI and MTL-SWEI. In 1.5 mm targets, STL-SWEI achieves alternately the tightest resolution (0.3 mm at CNR = 3.5 for a 0.17 mm filter) and highest CNR (8.5 with edge width = 0.7 mm for a 0.66 mm filter) of the modalities, followed by ARFI and then MTL-SWEI. In larger, 6 mm targets, the CNR-resolution tradeoff curves for ARFI and STL-SWEI overlap for ARFI time steps up to 0.5 ms and kernels ≤ 1 mm for STL-SWEI. STL-SWEI can operate either with a 25 dB improvement over MTL-SWEI in CNR at the same resolution, or with edge widths 5 × as narrow at equivalent CNR values, depending on the selection of regression filter size. Ex vivo ablations are used to demonstrate that ARFI, STL-SWEI and MTL-SWEI each resolve ablation lesions between 0.5 and 1 cm in diameter and gaps between lesions smaller than 5 mm in 3-D scans. Differences in contrast, noise, and resolution between the modalities are discussed. All three modalities are also shown to resolve ``x''-shaped ablations up to 22 mm in depth with good visual fidelity and correspondence to surface photographs, with STL-SWEI providing the highest quality images. Series of each type of image, registered using 3-D data from an electroanatomical mapping system, are used to build volumes that show ablations in in vivo canine atria. In vivo images are shown to be subject to increased noise due to tissue and transducer motion, and the challenges facing the proposed system are discussed. Ultimately, intracardiac acoustic radiation force methods are demonstrated to be promising tools for characterizing dynamic myocardial elasticity and imaging radiofrequency ablation lesions. Advisors/Committee Members: Trahey, Gregg E (advisor).

Subjects/Keywords: Biomedical engineering; Acoustic Radiation Force; Elasticity; Intracardiac Echocardiography; Shear Wave Elasticity Imaging; Ultrasound

11 more images…

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APA (6^th Edition):

Hollender, P. J. (2014). Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/9388

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

Chicago Manual of Style (16^th Edition):

Hollender, Peter J. “Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods .” 2014. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/9388.

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

MLA Handbook (7^th Edition):

Hollender, Peter J. “Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods .” 2014. Web. 21 Jan 2021.

Vancouver:

Hollender PJ. Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods . [Internet] [Thesis]. Duke University; 2014. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/9388.

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

Council of Science Editors:

Hollender PJ. Mapping Myocardial Elasticity with Intracardiac Acoustic Radiation Force Impulse Methods . [Thesis]. Duke University; 2014. Available from: http://hdl.handle.net/10161/9388

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

Duke University

19. Lipman, Samantha. Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation .

Degree: 2018, Duke University

URL: http://hdl.handle.net/10161/16947

► Hepatocellular carcinoma (HCC) lesions are often preceded by liver cirrhosis or Hepatitis C, and patients with these diagnoses are monitored every six months with… (more)

▼ Hepatocellular carcinoma (HCC) lesions are often preceded by liver cirrhosis or Hepatitis C, and patients with these diagnoses are monitored every six months with an ultrasound screening. B-mode ultrasound is an ideal imaging modality for regular screening; however, ultrasound has demonstrated a low sensitivity for detecting small, early stage HCCs. Studies using ultrasonic elasticity methods have shown increased HCC lesion contrast compared to B-mode ultrasound. This thesis presents the preliminary work of shear wave elasticity imaging (SWEI) methods to improve estimates of viscoelastic parameters in the context of liver screening for tumors, with the goals of (1) using multi-dimensional directional filtering and shear wave reconstruction to reduce reflection artifacts, (2) evaluating bias introduced from small depth-of-field (DOF) excitations into frequency dependent shear wave speed (SWS) and attenuation estimates and (3) evaluating the feasibility of combining on-axis and off-axis elasticity methods to screen the entire liver. Interfaces of different shear stiffness causes propagating shear waves to be reflected, which can lead to artifacts in SWS reconstructions due to the reflections both in and out of the imaging plane. Two-dimensional (2-D), three-dimensional (3-D), and four- dimensional (4-D) directional filters were applied to shear wave data, and SWS images were reconstructed with 2-D and 3-D shear wave reconstruction methods to quantify the reduction in image artifacts. For 2-D SWS image reconstructions, 3-D directional filters showed greater improvements in image quality than 2-D filters, and 4-D directional filters showed marginal improvement over 3-D filters. The 4-D directional filters have the largest impact in reducing reflection artifacts in 3-D SWS volumes. Commercial scanners reconstruct shear wave speeds for a region of interest using time-of-flight (TOF) methods reporting a single SWS (or elastic modulus) to the end user under the assumptions that tissue is elastic and independent of frequency. Human tissues are known to be viscoelastic (VE), resulting in dispersion and attenuation. Existing methods to quantify shear wave dispersion and attenuation commonly make an assumption that the acoustic radiation force excitation acts as a cylindrical source with a known geometric shear wave amplitude decay. The bias in shear dispersion and attenuation estimates associated with making this cylindrical wave assumption (up to 15% for dispersion and 41% for attenuation) when applied to shear wave sources with finite depth extents in realistic focal geometries is greater for more tightly-focused acoustic radiation force sources with smaller DOF. Curvilinear transducers are the standard probe used in ultrasound HCC screenings; however, previous studies using curvilinear arrays performing liver SWEI have been limited by penetration depth of the acoustic radiation force excitation. In order for SWEI to be feasible as an imaging method to screen for and detect HCC lesions, large, low… Advisors/Committee Members: Nightingale, Kathryn (advisor).

Subjects/Keywords: Medical imaging; Biomedical engineering; Acoustic Radiation Force; Elasticity Imaging; Shear Wave; Ultrasound; Viscoelastic

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

APA (6^th Edition):

Lipman, S. (2018). Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/16947

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

Chicago Manual of Style (16^th Edition):

Lipman, Samantha. “Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation .” 2018. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/16947.

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

MLA Handbook (7^th Edition):

Lipman, Samantha. “Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation .” 2018. Web. 21 Jan 2021.

Vancouver:

Lipman S. Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation . [Internet] [Thesis]. Duke University; 2018. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/16947.

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

Council of Science Editors:

Lipman S. Multi-Dimensional Ultrasonic Shear Wave Reconstructions: Improving the Accuracy of Viscoelastic Parameter Estimation . [Thesis]. Duke University; 2018. Available from: http://hdl.handle.net/10161/16947

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

20. SHAHROKH SEPEHRI RAHNAMA. COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES.

Degree: 2015, National University of Singapore

URL: http://scholarbank.nus.edu.sg/handle/10635/121726

Subjects/Keywords: Acoustic Radiation Force; Interparticle force; Acoustic Streaming; Acoustophoresis; Numerical Methods; Microfluidics

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APA (6^th Edition):

RAHNAMA, S. S. (2015). COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES. (Thesis). National University of Singapore. Retrieved from http://scholarbank.nus.edu.sg/handle/10635/121726

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

Chicago Manual of Style (16^th Edition):

RAHNAMA, SHAHROKH SEPEHRI. “COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES.” 2015. Thesis, National University of Singapore. Accessed January 21, 2021. http://scholarbank.nus.edu.sg/handle/10635/121726.

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

MLA Handbook (7^th Edition):

RAHNAMA, SHAHROKH SEPEHRI. “COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES.” 2015. Web. 21 Jan 2021.

Vancouver:

RAHNAMA SS. COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES. [Internet] [Thesis]. National University of Singapore; 2015. [cited 2021 Jan 21]. Available from: http://scholarbank.nus.edu.sg/handle/10635/121726.

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

Council of Science Editors:

RAHNAMA SS. COMPUTATION OF ACOUSTIC RADIATION AND INTERPARTICLE FORCES FOR SPHERES IN MICROFLUIDIC DEVICES. [Thesis]. National University of Singapore; 2015. Available from: http://scholarbank.nus.edu.sg/handle/10635/121726

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

Penn State University

21. Nama, Nitesh. MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK.

Degree: 2017, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/13950nxn144

► The lab-on-a-chip concept refers to the quest of integrating numerous functionalities onto a single microchip for applications within medicine and biotechnology. To achieve precise fluid… (more)

▼ The lab-on-a-chip concept refers to the quest of integrating numerous functionalities onto a single microchip for applications within medicine and biotechnology. To achieve precise fluid and particle handling capabilities required for such applications, microacoustofluidics (i.e. the merger of acoustics and microfluidics) has shown great potential. The primary motivation of this dissertation is to revisit the formulation of the governing equations for microacoustofluidics in an fluid-structure interaction (FSI) context to develop a numerical formulation that is transparent with regards to the reference frames as well as the time-scale separation. In this context, we present a generalized Lagrangian formulation by posing our governing equations over a convenient mean configuration that does not coincide with the current configurations. The formulation stems from an explicit separation of time-scales resulting in two subproblems: a first-order problem, formulated in terms of the fluid displacement at the fast scale, and a second-order problem formulated in terms of the Lagrangian flow velocity at the slow time scale. Following a rigorous time-averaging procedure, the second-order problem is shown to be intrinsically steady, and with exact boundary conditions at the oscillating walls. Also, as the second-order problem is solved directly for the Lagrangian velocity, the formulation does not need to employ the notion of Stokes drift, or any associated post-processing, thus facilitating a direct comparison with experiments. Because the first-order problem is formulated in terms of the displacement field, our formulation is directly applicable to more complex fluid-structure interaction problems in microacoustofluidics. We also present a comparison of the generalized Lagrangian formulation with the typically employed Eulerian formulation and highlight the superior numerical performance of our formulation to aid easier comparison with the experimental observations. Next, we describe the fluid and particle motion in acoustically-actuated, confined, leaky systems. The investigated model system is a microchip typically used for biomedical analyses; a liquid-filled polydimethylsiloxane microchannel driven acoustically by inter-digital transducers. Through a combination of quantitative experimental measurements and numerical results, we reveal the full three dimensional motion of the fluids and suspended particles. By varying the size of suspended particles, we capture the two limits for which the particle motion is dominated by the acoustic streaming drag to which it is dominated by the acoustic radiation force. The observed fluid and particle motion is captured numerically without any fitting parameter by a reduced-fluid model based on a thermoviscous, Lagrangian velocity-based formulation. Through a combination of experimental observations and precise numerical boundary conditions, we remove the existing ambiguity in the literature concerning the acoustic streaming direction as well as the critical particle size for which the… Advisors/Committee Members: Francesco Costanzo, Dissertation Advisor/Co-Advisor, Tony Jun Huang, Committee Chair/Co-Chair, Jonathan Pitt, Committee Member, Francesco Costanzo, Committee Member, Peter Butler, Outside Member.

Subjects/Keywords: Microfluidics; Arbitrary Lagrangian Eulerian Method; Acoustofluidics; Surface Acoustic Wave; Finite Element Method; Immersed Finite Element Method; Fluid-Structure Interaction; Acoustic Streaming; Acoustic radiation Force

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APA (6^th Edition):

Nama, N. (2017). MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/13950nxn144

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

Chicago Manual of Style (16^th Edition):

Nama, Nitesh. “MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK.” 2017. Thesis, Penn State University. Accessed January 21, 2021. https://submit-etda.libraries.psu.edu/catalog/13950nxn144.

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

MLA Handbook (7^th Edition):

Nama, Nitesh. “MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK.” 2017. Web. 21 Jan 2021.

Vancouver:

Nama N. MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK. [Internet] [Thesis]. Penn State University; 2017. [cited 2021 Jan 21]. Available from: https://submit-etda.libraries.psu.edu/catalog/13950nxn144.

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

Council of Science Editors:

Nama N. MICROACOUSTOFLUIDICS: AN ARBITRARY LAGRANGIAN-EULERIAN FRAMEWORK. [Thesis]. Penn State University; 2017. Available from: https://submit-etda.libraries.psu.edu/catalog/13950nxn144

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

KTH

22. Leuthner, Moritz. Improving cell secretome analysis and bacteria evolution by means of acoustophoresis.

Degree: Biotechnology and Health (CBH), 2020, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285985

► In both, cell secretome analysis and bacteria evolution, controlled handling of particles with a few to sub-micrometers in size and media exchange are inevitable… (more)

Subjects/Keywords: acoustophoresis; acoustofluidic; lab-on-a-chip; acoustic streaming; acoustic radiation force; particle trapping; particle washing; bulk acoustic waves; BAW; media exchange; cell manipulation; Medical Engineering; Medicinteknik

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

APA (6^th Edition):

Leuthner, M. (2020). Improving cell secretome analysis and bacteria evolution by means of acoustophoresis. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285985

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

Chicago Manual of Style (16^th Edition):

Leuthner, Moritz. “Improving cell secretome analysis and bacteria evolution by means of acoustophoresis.” 2020. Thesis, KTH. Accessed January 21, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285985.

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

MLA Handbook (7^th Edition):

Leuthner, Moritz. “Improving cell secretome analysis and bacteria evolution by means of acoustophoresis.” 2020. Web. 21 Jan 2021.

Vancouver:

Leuthner M. Improving cell secretome analysis and bacteria evolution by means of acoustophoresis. [Internet] [Thesis]. KTH; 2020. [cited 2021 Jan 21]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285985.

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

Council of Science Editors:

Leuthner M. Improving cell secretome analysis and bacteria evolution by means of acoustophoresis. [Thesis]. KTH; 2020. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285985

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

23. Ben Haj Slama, Rafika. Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow.

Degree: Docteur es, Mécanique des fluides et acoustique, 2018, Lyon; École nationale d'Ingénieurs de Monastir (Tunisie)

URL: http://www.theses.fr/2018LYSE1009

►

Les travaux de recherche du présent projet se situent dans le contexte général de l'optimisation de la technique de sono-thrombolyse (destruction d'un caillot sanguin ou… (more)

▼

Les travaux de recherche du présent projet se situent dans le contexte général de l'optimisation de la technique de sono-thrombolyse (destruction d'un caillot sanguin ou d'un thrombus par cavitation ultrasonore). En effet, certes cette technique a plusieurs avantages par rapport à la solution chirurgicale, mais elle présente des limitations qui sont principalement le risque de libération de fragments du thrombus, susceptibles d'engendrer l'embolie pulmonaire. Face à ces limites actuelles que de la technique de sono-thrombolyse, s'est imposée la nécessité de pousser plus loin les recherches pour mieux comprendre les mécanismes qui la régissent. D'où le projet de la présente thèse qui s'intéresse plus particulièrement aux écoulements générés lors de l'application des ultrasons focalisés dans un liquide. L'objet du présent travail consiste à étudier minutieusement les phénomènes hydrodynamiques et acoustiques, en particulier le streaming acoustique du fluide et la force de radiation ultrasonore agissant sur les particules solides. Cela permettra d'obtenir une connaissance profonde des phénomènes hydrodynamiques se produisant lors de l'application des HIFU dans un milieu liquide chargé de particules.La technique optique de PIV a été adoptée pour mesurer l'écoulement du fluide ainsi que des particules solides. Ceci a permis de caractériser le streaming acoustique induit par la propagation des ultrasons focalisés dans un milieu liquide infini, de le comparer à un écoulement classique de type jet circulaire libre, et de déterminer un diamètre critique au-dessus du quel l'écoulement des particules solides sphériques dans un liquide est dominée par la force de radiation ultrasonore plutôt que par l'entrainement du streaming acoustique. Comme approche numérique, un outil de simulation CFD a été utilisé afin de modéliser le même écoulement de streaming en question et afin de comparer les résultats numériques avec les résultats expérimentaux obtenus

The research work of this project is provided in the context of sono-thrombolysis technique optimization (blood clot or thrombus destruction by ultrasonic cavitation). Indeed, although this technique has several advantages over the surgical solution, but it has limitations that are mainly the risk of thrombus fragments releasing in the circulation, likely to induce pulmonary embolism.In view of these sono-thrombolysis technique current limitations, it has become necessary to carry out further research to better understand the mechanisms that govern it. Hence, comes the project of the present thesis, which is particularly interested in the flows generated by the application of focused ultrasound in a liquid. The purpose of the present work is to accurately study the hydrodynamic and acoustic phenomena, in particular the fluid acoustic streaming and the ultrasound radiation force acting on solid particles. This would provide a deep understanding of the hydrodynamic phenomena occurring during HIFU (High Intensity Focused Ultrasound) application in a liquid medium with…

Advisors/Committee Members: Béra, Jean-Christophe (thesis director), Gilles, Bruno (thesis director), Ben Chiekh, Maher (thesis director).

Subjects/Keywords: Ultrasons focalisés; Écoulements; Streaming acoustique; Force de radiation; PIV; CFD; Jet circulaire; Focused ultrasound; Flows; Acoustic streaming; Radiation force; PIV; CFD; Circular jet; 532

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APA (6^th Edition):

Ben Haj Slama, R. (2018). Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow. (Doctoral Dissertation). Lyon; École nationale d'Ingénieurs de Monastir (Tunisie). Retrieved from http://www.theses.fr/2018LYSE1009

Chicago Manual of Style (16^th Edition):

Ben Haj Slama, Rafika. “Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow.” 2018. Doctoral Dissertation, Lyon; École nationale d'Ingénieurs de Monastir (Tunisie). Accessed January 21, 2021. http://www.theses.fr/2018LYSE1009.

MLA Handbook (7^th Edition):

Ben Haj Slama, Rafika. “Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow.” 2018. Web. 21 Jan 2021.

Vancouver:

Ben Haj Slama R. Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow. [Internet] [Doctoral dissertation]. Lyon; École nationale d'Ingénieurs de Monastir (Tunisie); 2018. [cited 2021 Jan 21]. Available from: http://www.theses.fr/2018LYSE1009.

Council of Science Editors:

Ben Haj Slama R. Écoulements générés en milieu fluide par une onde ultrasonore focalisée : streaming acoustique et écoulement de particules solides : Flows generated by a focused ultrasound wave in a liquid medium : acoustic streaming and solid particles flow. [Doctoral Dissertation]. Lyon; École nationale d'Ingénieurs de Monastir (Tunisie); 2018. Available from: http://www.theses.fr/2018LYSE1009

University of Rochester

24. Mercado, Karla Patricia E. Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues.

Degree: PhD, 2015, University of Rochester

URL: http://hdl.handle.net/1802/29710

► Tissue engineering holds great promise for the repair or replacement of native tissues and organs. Further advancements in the fabrication of functional engineered tissues are… (more)

Subjects/Keywords: Biomaterials; High-frequency ultrasound; Integrated backscatter coefficient; Tissue characterization; Tissue engineering; Ultrasound elastography; Collagen hydrogels; Acoustic radiation force elasticity imaging

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

APA (6^th Edition):

Mercado, K. P. E. (2015). Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/29710

Chicago Manual of Style (16^th Edition):

Mercado, Karla Patricia E. “Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues.” 2015. Doctoral Dissertation, University of Rochester. Accessed January 21, 2021. http://hdl.handle.net/1802/29710.

MLA Handbook (7^th Edition):

Mercado, Karla Patricia E. “Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues.” 2015. Web. 21 Jan 2021.

Vancouver:

Mercado KPE. Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues. [Internet] [Doctoral dissertation]. University of Rochester; 2015. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/1802/29710.

Council of Science Editors:

Mercado KPE. Developing high-frequency quantitative ultrasound techniques to characterize three-dimensional engineered tissues. [Doctoral Dissertation]. University of Rochester; 2015. Available from: http://hdl.handle.net/1802/29710

25. Saunders, Catherine. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.

Degree: 2014, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:224680

► Small-amplitude, high-frequency (ultrasound) forcing of fluid/particle systems is being used in a number of applications associated with non-destructive fluid mixing and the movement/manipulation of particles… (more)

▼ Small-amplitude, high-frequency (ultrasound) forcing of fluid/particle systems is being used in a number of applications associated with non-destructive fluid mixing and the movement/manipulation of particles in suspension. Of most importance in this context are the second-order, steady, effects arising from the nonlinear interaction of a leading-order oscillatory field with itself. In this thesis we consider some of these steady effects in both incompressible and compressible fluids.We first consider the axisymmetric steady streaming generated in an incompressible, viscous fluid contained between two (radially) infinite parallel plates, each oscillating in a direction normal to its own plane. In the limit of small-amplitude, high-frequency oscillations, we show that the steady-streaming flow in the fluid bulk is driven by thin streaming sublayers at the plates, at which the normal velocity is zero and the radial velocity varies linearly with distance from the axis of rotational symmetry. Effectively, in the bulk flow, the bounding plates appear as (no-slip) impermeable walls that stretch radially. This bulk-flow problem is extended to allow for the analogous steady flow of two immiscible, incompressible, viscous fluids, each undergoing a radial-stretching motion appropriate to high-frequency steady streaming. For a flat interface between the fluids, a self-similar solution reduces the Navier – Stokes equations to a nonlinear boundary-value problem, the solution of which exhibits an interesting structure in the limit of large Reynolds number. In this limit, solutions can be found using matched asymptotic expansions, but the location of the interface between the fluids can only be determined if terms that are exponentially small in the Reynolds number are included. It is shown that for fluids of almost-equal densities, exponentially-small differences can have a leading-order effect on the observed flow.The second part of the thesis is concerned with the (steady) acoustic radiation force on a rigid sphere submerged in a compressible, inviscid fluid, when the wavelength of the incident acoustic field is large compared to the radius of the sphere. In this limit, a matched asymptotic expansion method is used to derive an expression for the acoustic radiation force, on both fixed and free rigid spheres, due to a range of incident fields. For incident acoustic fields that are appropriate to planar and circular waveguides/channels, expressions are derived for the scattered field and the radiation force on a rigid sphere in the long-wavelength limit. Fixed and free spheres located both on and off the axis of symmetry of these incident fields are considered. This is an extension to the current literature, in which numerical methods are used to examine the scattering from spheres in an off-axis position, and problems are restricted to the consideration of fixed spheres only. It is shown that there are stable and unstable positions within the waveguide where any off-axis acoustic radiation force vanishes, leaving only an… Advisors/Committee Members: Hewitt, Richard.

Subjects/Keywords: Asymptotic methods; Steady streaming; Acoustic radiation force

…The magnitude of the acoustic radiation force F2 due to a plane wave of half-amplitude A… …166 3.9 The dependence of the O (ε2 α6 ) dimensionless acoustic radiation force… …acoustic radiation force F2 on free spherical particles of density 500, 1000 and 3000 kg m−3… …x28;ε2 α4 ) dimensionless acoustic radiation force F2 on free spherical particles of… …dimensionless acoustic radiation force F2 on free spherical particles of density 500, 1000 and 3000…

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

APA (6^th Edition):

Saunders, C. (2014). Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:224680

Chicago Manual of Style (16^th Edition):

Saunders, Catherine. “Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.” 2014. Doctoral Dissertation, University of Manchester. Accessed January 21, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:224680.

MLA Handbook (7^th Edition):

Saunders, Catherine. “Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces.” 2014. Web. 21 Jan 2021.

Vancouver:

Saunders C. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2021 Jan 21]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:224680.

Council of Science Editors:

Saunders C. Asymptotic methods applied to problems of steady-streaming flows and acoustic radiation forces. [Doctoral Dissertation]. University of Manchester; 2014. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:224680

Duke University

26. Doherty, Joshua Ryan. Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging .

Degree: 2014, Duke University

URL: http://hdl.handle.net/10161/8715

► The rupture of arterial plaques is the most common cause of ischemic complications including stroke, the fourth leading cause of death and number one… (more)

▼ The rupture of arterial plaques is the most common cause of ischemic complications including stroke, the fourth leading cause of death and number one cause of long term disability in the United States. Unfortunately, because conventional diagnostic tools fail to identify plaques that confer the highest risk, often a disabling stroke and/or sudden death is the first sign of disease. A diagnostic method capable of characterizing plaque vulnerability would likely enhance the predictive ability and ultimately the treatment of stroke before the onset of clinical events. This dissertation evaluates the hypothesis that Acoustic Radiation Force Impulse (ARFI) imaging can noninvasively identify lipid regions, that have been shown to increase a plaque's propensity to rupture, within carotid artery plaques in vivo. The work detailed herein describes development efforts and results from simulations and experiments that were performed to evaluate this hypothesis. To first demonstrate feasibility and evaluate potential safety concerns, finite-element method simulations are used to model the response of carotid artery plaques to an acoustic radiation force excitation. Lipid pool visualization is shown to vary as a function of lipid pool geometry and stiffness. A comparison of the resulting Von Mises stresses indicates that stresses induced by an ARFI excitation are three orders of magnitude lower than those induced by blood pressure. This thesis also presents the development of a novel pulse inversion harmonic tracking method to reduce clutter-imposed errors in ultrasound-based tissue displacement estimates. This method is validated in phantoms and was found to reduce bias and jitter displacement errors for a marked improvement in image quality in vivo. Lastly, this dissertation presents results from a preliminary in vivo study that compares ARFI imaging derived plaque stiffness with spatially registered composition determined by a Magnetic Resonance Imaging (MRI) gold standard in human carotid artery plaques. It is shown in this capstone experiment that lipid filled regions in MRI correspond to areas of increased displacement in ARFI imaging while calcium and loose matrix components in MRI correspond to uniformly low displacements in ARFI imaging. This dissertation provides evidence to support that ARFI imaging may provide important prognostic and diagnostic information regarding stroke risk via measurements of plaque stiffness. More generally, the results have important implications for all acoustic radiation force based imaging methods used clinically. Advisors/Committee Members: Trahey, Gregg E (advisor).

Subjects/Keywords: Medical imaging and radiology; Biomedical engineering; Acoustics; acoustic radiation force; atherosclerosis; harmonic tracking; plaque; stroke; ultrasound elasticity imaging

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APA (6^th Edition):

Doherty, J. R. (2014). Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/8715

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

Chicago Manual of Style (16^th Edition):

Doherty, Joshua Ryan. “Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging .” 2014. Thesis, Duke University. Accessed January 21, 2021. http://hdl.handle.net/10161/8715.

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

MLA Handbook (7^th Edition):

Doherty, Joshua Ryan. “Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging .” 2014. Web. 21 Jan 2021.

Vancouver:

Doherty JR. Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging . [Internet] [Thesis]. Duke University; 2014. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10161/8715.

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

Council of Science Editors:

Doherty JR. Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging . [Thesis]. Duke University; 2014. Available from: http://hdl.handle.net/10161/8715

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

Harvard University

27. Mutafopulos, Kiryakos S. Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis.

Degree: PhD, 2019, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029592

►

Microfluidics enables researchers and clinicians to manipulate fluids, particles, and cells at the micron scale, providing a vast array of potential methods for studying cell… (more)

Subjects/Keywords: Microfluidics; Surface Acoustic Waves; SAW; Droplets; Cell Sorting; Cell Encapsulation; Flow Cytometry; Cell Lysis; Droplet Storage; Interdigital Transducers; IDT; Acoustic Radiation Force

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

APA (6^th Edition):

Mutafopulos, K. S. (2019). Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029592

Chicago Manual of Style (16^th Edition):

Mutafopulos, Kiryakos S. “Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis.” 2019. Doctoral Dissertation, Harvard University. Accessed January 21, 2021. http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029592.

MLA Handbook (7^th Edition):

Mutafopulos, Kiryakos S. “Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis.” 2019. Web. 21 Jan 2021.

Vancouver:

Mutafopulos KS. Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis. [Internet] [Doctoral dissertation]. Harvard University; 2019. [cited 2021 Jan 21]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029592.

Council of Science Editors:

Mutafopulos KS. Microfluidic Device Technology for Cell and Droplet Sorting, Encapsulation, Storage, and Lysis. [Doctoral Dissertation]. Harvard University; 2019. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029592

University of Lund

28. Augustsson, Per. On microchannel acoustophoresis - Experimental considerations and life science applications.

Degree: 2011, University of Lund

URL: https://lup.lub.lu.se/record/2203054 ; https://portal.research.lu.se/ws/files/5408028/2203068.pdf

► This thesis presents experimental studies of microchannel acoustophoresis, a technique for manipulation of microscopic objects in suspension by means of acoustic radiation forces induced by… (more)

Subjects/Keywords: Medical Engineering; microtechnology; microfluidics; lab on a chip; separation; acoustophoresis; ultrasound; acoustic resonance; acoustic radiation force; phage display; circulating tumour cells; acoustofluidics

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

APA (6^th Edition):

Augustsson, P. (2011). On microchannel acoustophoresis - Experimental considerations and life science applications. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/2203054 ; https://portal.research.lu.se/ws/files/5408028/2203068.pdf

Chicago Manual of Style (16^th Edition):

Augustsson, Per. “On microchannel acoustophoresis - Experimental considerations and life science applications.” 2011. Doctoral Dissertation, University of Lund. Accessed January 21, 2021. https://lup.lub.lu.se/record/2203054 ; https://portal.research.lu.se/ws/files/5408028/2203068.pdf.

MLA Handbook (7^th Edition):

Augustsson, Per. “On microchannel acoustophoresis - Experimental considerations and life science applications.” 2011. Web. 21 Jan 2021.

Vancouver:

Augustsson P. On microchannel acoustophoresis - Experimental considerations and life science applications. [Internet] [Doctoral dissertation]. University of Lund; 2011. [cited 2021 Jan 21]. Available from: https://lup.lub.lu.se/record/2203054 ; https://portal.research.lu.se/ws/files/5408028/2203068.pdf.

Council of Science Editors:

Augustsson P. On microchannel acoustophoresis - Experimental considerations and life science applications. [Doctoral Dissertation]. University of Lund; 2011. Available from: https://lup.lub.lu.se/record/2203054 ; https://portal.research.lu.se/ws/files/5408028/2203068.pdf

Drexel University

29. Freeman, Paul Timothy. Coning reduction in spinning flying vehicles.

Degree: 2011, Drexel University

URL: http://hdl.handle.net/1860/3887

►

Gun launched projectiles designed to maintain body spin can often exhibit a gyroscopic phenomenon called coning. Coning can increase a projectile's susceptibility to loss of… (more)

Subjects/Keywords: Mechanical engineering; Projectiles; Impulse Force Method

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APA (6^th Edition):

Freeman, P. T. (2011). Coning reduction in spinning flying vehicles. (Thesis). Drexel University. Retrieved from http://hdl.handle.net/1860/3887

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

Chicago Manual of Style (16^th Edition):

Freeman, Paul Timothy. “Coning reduction in spinning flying vehicles.” 2011. Thesis, Drexel University. Accessed January 21, 2021. http://hdl.handle.net/1860/3887.

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

MLA Handbook (7^th Edition):

Freeman, Paul Timothy. “Coning reduction in spinning flying vehicles.” 2011. Web. 21 Jan 2021.

Vancouver:

Freeman PT. Coning reduction in spinning flying vehicles. [Internet] [Thesis]. Drexel University; 2011. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/1860/3887.

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

Council of Science Editors:

Freeman PT. Coning reduction in spinning flying vehicles. [Thesis]. Drexel University; 2011. Available from: http://hdl.handle.net/1860/3887

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

30. Jiménez González, Noe. Nonlinear Acoustic Waves in Complex Media .

Degree: 2015, Universitat Politècnica de València

URL: http://hdl.handle.net/10251/53237

► [EN] Nature is nonlinear. The linear description of physical phenomena is useful for explain observations with the simplest mathematical models, but they are only accurate… (more)

▼ [EN] Nature is nonlinear. The linear description of physical phenomena is useful for explain observations with the simplest mathematical models, but they are only accurate for a limited range of input values. In the case of intense acoustics waves, linear models obviate a wide range of physical phenomena that are necessary for accurately describe such high-amplitude waves, indispensable for explain other exotic acoustic waves and mandatory for developing new applied techniques based on nonlinear processes. In this Thesis we study the interactions between nonlinearity and other basic wave phenomena such as non-classical attenuation, anisotropic dispersion and periodicity, and diffraction in specific configurations. First, we present intense strain waves in a chain of cations coupled by realistic interatomic potentials. Here, the nonlinear ionic interactions and lattice dispersion lead to the formation of supersonic kinks. These intrinsically-nonlinear localized dislocations travel long distances without changing its properties and explain the formation of dark traces in mica crystals. Then, we analyze nonlinear wave processes in a system composed of multilayered acoustic media. The rich nonlinear dynamics of this system is characterized by its strong dispersion. Here, harmonic generation processes and the relation with its band structure are presented, showing that the nonlinear processes can be enhanced, strongly minimized or simply modified by tuning the layer parameters. In this way, we show how the dynamics of intense monochromatic waves and acoustic solitons can be controlled by artificial layered materials. In a second part, we include diffraction and analyze four types of singular beams. First, we study nonlinear beams in two dimensional sonic crystals. In this system, the inclusion of anisotropic dispersion is tuned for obtain simultaneous self-collimation for fundamental and second harmonic beams. The conditions for optimal second harmonic generation are presented. Secondly, we present limited diffraction beam generation using equispaced axisymmetric diffraction gratings. The obtained beams are truncated version of zero-th order Bessel beams. Third, the grating spacing can be modified to achieve focusing, where the generated nonlinear beams presents high gain, around 30 dB, with a focal width which is between the diffraction limit and the sub-wavelength regime, but with its characteristic high amplitude side lobes strongly reduced. Finally, we observe that waves diffracted by spiral-shaped gratings generate high-order Bessel beams, conforming nonlinear acoustic vortex. The conditions to obtain arbitrary-order Bessel beams by these passive elements are presented. Finally, the interplay of nonlinearity and attenuation in biological media is studied in the context of medical ultrasound. First, a numerical method is developed. The method solves the constitutive relations for nonlinear acoustics and the frequency power law attenuation of biological media is modeled as a sum of relaxation processes. A new… Advisors/Committee Members: Camarena Femenia, Francisco (advisor), Redondo Pastor, Francisco Javier (advisor).

Subjects/Keywords: Nonlinear Acoustics; Ultrasound; FDTD; Nonlinear Lattices; Nonlinear Dispersion; Acoustic Solitons; Kinks; Soft Tissue; Frequency Power Law Attenuation; Nonlinear Attenuation; Nonlinear Beams; Bessel Beams; Fresnel Zone Plates; High Order Bessel Beams; HOBB; Acosutic radiation force; Radiation force; Acoustic relaxation; Nonlinear lattice dynamics; Nonlinear physics; Complex media; Acoustic complex media; Ultrasound medical applications

11 more images…

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

APA (6^th Edition):

Jiménez González, N. (2015). Nonlinear Acoustic Waves in Complex Media . (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/53237

Chicago Manual of Style (16^th Edition):

Jiménez González, Noe. “Nonlinear Acoustic Waves in Complex Media .” 2015. Doctoral Dissertation, Universitat Politècnica de València. Accessed January 21, 2021. http://hdl.handle.net/10251/53237.

MLA Handbook (7^th Edition):

Jiménez González, Noe. “Nonlinear Acoustic Waves in Complex Media .” 2015. Web. 21 Jan 2021.

Vancouver:

Jiménez González N. Nonlinear Acoustic Waves in Complex Media . [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2015. [cited 2021 Jan 21]. Available from: http://hdl.handle.net/10251/53237.

Council of Science Editors:

Jiménez González N. Nonlinear Acoustic Waves in Complex Media . [Doctoral Dissertation]. Universitat Politècnica de València; 2015. Available from: http://hdl.handle.net/10251/53237

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Open Access Theses and Dissertations