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Biomedical Engineering and Bioengineering Commons

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2013

Biological Engineering

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Articles 1 - 30 of 45

Full-Text Articles in Biomedical Engineering and Bioengineering

Temperature-Dependent Dielectric And Thermal Properties Of Whey Protein Gel And Mashed Potato, Jiajia Chen, Krishnamoorthy Pitchai, Sohan Birla, Ricardo Gonzalez, David Jones, Jeyamkondan Subbiah Dec 2013

Temperature-Dependent Dielectric And Thermal Properties Of Whey Protein Gel And Mashed Potato, Jiajia Chen, Krishnamoorthy Pitchai, Sohan Birla, Ricardo Gonzalez, David Jones, Jeyamkondan Subbiah

Biological Systems Engineering: Papers and Publications

Temperature-dependent dielectric properties (dielectric constant and dielectric loss factor) and thermal properties (thermal conductivity and specific heat capacity) of whey protein gel and mashed potato were measured from -20°C to 100°C. A dielectric properties measurement system and a multipoint temperature calibration protocol were developed. The system consists of an impedance analyzer, a high-temperature coaxial cable, a high-temperature coaxial probe, a micro-climatic chamber and a metal sample holder. Calibrations at two temperatures (25°C and 85°C) were sufficient to accurately measure the dielectric properties of foods from frozen to hot temperatures. Both dielectric constant and dielectric loss factor ...


Conventional And Catalytic Pyrolysis Of Pinyon Juniper Biomass, Bhuvanesh Kumar Yathavan Dec 2013

Conventional And Catalytic Pyrolysis Of Pinyon Juniper Biomass, Bhuvanesh Kumar Yathavan

All Graduate Theses and Dissertations

Pinyon and juniper are invasive woody species which has occupied more than 47 million acres of land in Western United States. Pinyon juniper woodlands domination decreases the herbaceous vegetation, increase bare lands which in turn increases soil erosion and nutrition loss. Thus, The US Bureau of Land Management (BLM) has focused on harvesting these woody species to make room for herbaceous vegetation. The major application of harvested pinyon-juniper (PJ) is low value firewood. Thus, there is a need to develop new high value products from this woody biomass to reduce the cost of harvesting. In this study pyrolysis was carried ...


Development Of A Computational Approach To Assess Hip Fracture And Repair: Considerations Of Intersubject And Surgical Alignment Variability, Azhar Ali Nov 2013

Development Of A Computational Approach To Assess Hip Fracture And Repair: Considerations Of Intersubject And Surgical Alignment Variability, Azhar Ali

Electronic Theses and Dissertations

Hip fracture remains a major public health concern due to the significant number of occurrences and mortality rates. Intertrochanteric fractures are the most common type of fracture and are typically caused by a fall. Intramedullary osteosynthesis is a common surgical practice to repair intertrochanteric fractures, but revisions are often required. The work presented in this thesis aims to improve the realism and fidelity of computational models of hip fracture, which can be an effective alternative to costly and labor-intensive clinical in-vivo and experimental in-vitro testing. Intersubject variability is inherently present in anatomy and material relations. Statistical shape and intensity models ...


Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus Oct 2013

Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Despite having progressed extensively in the field of synthetic biology in terms of DNA synthesis, analysis and transplanting, we still cannot reliably, quantitatively measure expression of new genetic constructs. We engineered a biobrick compatible expression cassette to control transcription and translation initiation which can be reused in new genetic contexts. Previous research has shown that the Bicistronic design have much lesser variations in expression with varying genes of interest as compared to the regular monocistronic design.(Mutalik, Endy, Guimaraes, Cambray, Lam, Juul, Tran & Paull, 2013) The Bicistronic design(BCD) consists of two Shine-Dalgarno sequences in its translation element which when ...


Determination Of Master Compliance Curve For Extruded Semolina Pasta, Laura E. Emery, Martin Okos Oct 2013

Determination Of Master Compliance Curve For Extruded Semolina Pasta, Laura E. Emery, Martin Okos

The Summer Undergraduate Research Fellowship (SURF) Symposium

The dependence of the rate of relaxation of semolina pasta on moisture content and temperature and how it affects shrinkage during drying has not yet been determined. The purpose of this research was to develop an equation that relates moisture content and temperature in order to obtain a master curve for creep of the product. When found, this equation could help to optimize the drying process and increase the quality of the final pasta product. Semolina flour mixed with water and propionic acid to create a 35% wet basis product was extruded on a C.W. Brabender 2523 to obtain ...


Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao Oct 2013

Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Engineering synthetic multicellular systems will lead to new synthetic biology technological platforms, inform developmental biology through recapitulation of natural systems and possibly unveil novel morphologies with practical applications not before reached throughout natural history (Maharbiz, 2012). Creating an exogenous molecular circuit that will polarize unicellular cells into “apical” and “basal” domains relative to a substrate plane would fulfill a missing component towards fully multicellular synthetic cellular communities (Maharbiz, 2012). To this end, a PIP3 polarization network previously designed by Chau and associates (Chau, Walter, Gerardin, Tang, Lim 2012) was coupled to the specific activation by niacin of a recombinant ...


Image Skeletal Muscle Progenitors In Situ To Investigate How The Ecm Composition Regulates Musculoskeletal Assembly, Andrew L. Schilb, Sarah Calve Oct 2013

Image Skeletal Muscle Progenitors In Situ To Investigate How The Ecm Composition Regulates Musculoskeletal Assembly, Andrew L. Schilb, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

Regenerative medicine has difficulty with the human body’s inability to functionally repair tissues lost as a result of disease or serious accident. Through tissue engineering, there has been development of various scaffolding with the purpose of enhancing skeletal muscle regrowth and functionality. The scaffolds are typically constructed from artificial polymers or decellularized extracellular matrix (ECM) that mimics adult tissue. These standardized scaffolds are hindered though by the host since tissue engineers have not taken into account of how the composition musculoskeletal ECM during tissue repair is dramatically different than that of a homeostatic adult. Now green fluorescent protein positive ...


Adhesive Elastomeric Proteins, Haefa Mansour, Julie Liu Oct 2013

Adhesive Elastomeric Proteins, Haefa Mansour, Julie Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Sutures and staples commonly used to close surgical wounds tend to be much stiffer than the surrounding tissue, often resulting in external tissue damage. Surgical adhesives provide a promising alternative to these sutures and staples. Ideal surgical adhesives are biocompatible, able to set well and remain sticky in moist conditions, possess strong adhesive and cohesive properties, and exhibit mechanical properties that mimic those of the surrounding tissue. Unfortunately, the adhesives available today are unable to satisfactorily meet all of these criteria. We are utilizing protein engineering techniques to design, create, and test a new surgical adhesive that combines the adhesive ...


Developing A Small-Footprint Bioengineering Program, Alisha Sarang-Sieminski, Debbie Chachra Sep 2013

Developing A Small-Footprint Bioengineering Program, Alisha Sarang-Sieminski, Debbie Chachra

Alisha L. Sarang-Sieminski

The field of bioengineering is rapidly changing and expanding to include not only more traditional bioengineering applications (e.g. device-focused areas such as prosthetics, imaging) but also more recent sub-fields and technologies(e.g. more biologically-focused areas such as those enabled by tissue engineering and microfluidics). This rapid change, coupled with the intrinsically interdisciplinary nature of bioengineering, presents a unique challenge to the developers of academic programs, as they need to both select relevant content and strike a balance between depth and breadth. We, the architects of the bioengineering program at the undergraduate-only Franklin W. Olin College of Engineering, which ...


Understanding Biocatalyst Inhibition By Carboxylic Acids, Laura R. Jarboe, Liam Royce, Ping Liu Sep 2013

Understanding Biocatalyst Inhibition By Carboxylic Acids, Laura R. Jarboe, Liam Royce, Ping Liu

Chemical and Biological Engineering Publications

Carboxylic acids are an attractive biorenewable chemical in terms of their flexibility and usage as precursors for a variety of industrial chemicals. It has been demonstrated that such carboxylic acids can be fermentatively produced using engineered microbes, such as Escherichia coli andSaccharomyces cerevisiae. However, like many other attractive biorenewable fuels and chemicals, carboxylic acids become inhibitory to these microbes at concentrations below the desired yield and titer. In fact, their potency as microbial inhibitors is highlighted by the fact that many of these carboxylic acids are routinely used as food preservatives. This review highlights the current knowledge regarding the ...


Effect Of Plant Hormones On The Production Of Biomass And Lipid In Microalgae, Malihe Mehdizadeh Allaf Aug 2013

Effect Of Plant Hormones On The Production Of Biomass And Lipid In Microalgae, Malihe Mehdizadeh Allaf

Electronic Thesis and Dissertation Repository

Limited fossil fuel reserves, increasing demand for energy in all parts of the world are some driving forces to look for new sources of transportation fuels. Among different options available, microalgae are currently attracting wide interests as an alternative and renewable fuel source.

Microalgae are single cell photosynthetic organisms that are known for rapid growth and high energy content and as a part of photosynthesis; they produce oil that can be used as a feedstock for biodiesel production. Some algae strains could contain lipid up to 80% of the dry biomass. The amount of lipid production is in direct relation ...


Life Support: Long Term Storage Of Solid Waste In An Enclosed Membrane System, Emmy O. Trieu, Michael Flynn, Rocco Mancinelli Aug 2013

Life Support: Long Term Storage Of Solid Waste In An Enclosed Membrane System, Emmy O. Trieu, Michael Flynn, Rocco Mancinelli

STAR (STEM Teacher and Researcher) Presentations

In deep space missions, maintaining life support is of the utmost priority. In such a closed system, human waste must be stored and treated. Simulated feces (ersatz) will be inoculated with microbes representing normal fecal flora, mixed with urine brine and shredded refuse of products typically used in space missions. Composting methods often use alternating layers of waste with scraps of carboniferous materials (finely shredded refuse). By preparing membrane bags with a homogenized ersatz and carboniferous refuse mixture and membrane bags with alternating layers of ersatz and carboniferous refuse, it may be possible to monitor anaerobic thermophillic digestion of the ...


Hybrid Nanostructured Textile Bioelectrode For Unobtrusive Health Monitoring, Pratyush Rai Aug 2013

Hybrid Nanostructured Textile Bioelectrode For Unobtrusive Health Monitoring, Pratyush Rai

Theses and Dissertations

Coronary heart disease, cardiovascular diseases and strokes are the leading causes of mortality in United States of America. Timely point-of-care health diagnostics and therapeutics for person suffering from these diseases can save thousands of lives. However, lack of accessible minimally intrusive health monitoring systems makes timely diagnosis difficult and sometimes impossible. To remedy this problem, a textile based nano-bio-sensor was developed and evaluated in this research. The sensor was made of novel array of vertically standing nanostructures that are conductive nano-fibers projecting from a conductive fabric. These sensor electrodes were tested for the quality of electrical contact that they made ...


Zein: Novel Natural Polymer For Nanoparticle- And Film-Mediated Gene Delivery, Jessica D. Taylor Jul 2013

Zein: Novel Natural Polymer For Nanoparticle- And Film-Mediated Gene Delivery, Jessica D. Taylor

Biological Systems Engineering--Dissertations, Theses, and Student Research

Gene delivery, the introduction of DNA into cells, is applicable to gene therapy, DNA vaccination, functional genomics and diagnostics, tissue engineering, and drug-eluting medical devices. Particulates incorporating DNA are promising vehicles for gene delivery and overcome some of the barriers that hinder successful gene transfer, with the ability to protect DNA and provide for controlled, localized, and sustained release and transfection. Furthermore, innovative new gene delivery strategies that incorporate DNA particulates or complexes within films or coatings for devices and scaffolds could further provide for controlled and sustained transfection at the site of implant. Zein, a hydrophobic protein from corn ...


Stent Graft Blush, Vanessa Barrett, Thomas Matzinger, Mike Morelli Jun 2013

Stent Graft Blush, Vanessa Barrett, Thomas Matzinger, Mike Morelli

Mechanical Engineering

In order to better understand Type IV endoleaks (“blush”), the Cal Poly Senior Project team GraftTest has developed a blush evaluation system able to mimic several of the aorta’s environmental parameters. Capable of both pressure and flow rate control, this bench top system accommodates Medtronic’s wide range of abdominal and thoracic aortic stent grafts. Having researched endoleaks, stent grafts, and numerous other factors affecting stent graft blush, a system was developed with the aim of assessing and comparing the performance of Medtronic’s stent grafts with regard to blush. Furthermore, this system has been designed to provide reliable ...


Beach Wheelchair Project, Rory Aronson, Joshua Marcum, Samuel Coyne, Alex Hayes, Alexa Colburn, Max Hessel, Benedikt Strauss, Marvin Rimmele, Marco Pietsch Jun 2013

Beach Wheelchair Project, Rory Aronson, Joshua Marcum, Samuel Coyne, Alex Hayes, Alexa Colburn, Max Hessel, Benedikt Strauss, Marvin Rimmele, Marco Pietsch

Mechanical Engineering

The Beach Wheelchair, Sandcrawler, is a machine intended to help give people with disabilities the full beach experience. The non-profit organization Bridge II Sports sponsored this project, and tasked us with developing the design and fabricating a prototype. This chair has several features including a linkage mechanism that raises and lowers a chair relative to an external frame, hand crank drive with Gates Carbondrive belt and sprockets, buoyant Wheeleez balloon tires, and much more.


Influence Of Carbon To Nitrogen Ratios On Soybean Somatic Embryo (Cv. Jack) Growth And Composition, Quyen Xuan Truong, Kaelynn Adele Koch, Jong Moon Yoon, John D. Everard, Jacqueline V. Shanks Jun 2013

Influence Of Carbon To Nitrogen Ratios On Soybean Somatic Embryo (Cv. Jack) Growth And Composition, Quyen Xuan Truong, Kaelynn Adele Koch, Jong Moon Yoon, John D. Everard, Jacqueline V. Shanks

Chemical and Biological Engineering Publications

Soybean [Glycine max (L.) Merr.] seed are valued for their protein and oil content. Soybean somatic embryos cultured in Soybean Histodifferentiation and Maturation (SHaM) medium were examined for their suitability as a model system for developing an understanding of assimilate partitioning and metabolic control points for protein and oil biosynthesis in soybean seed. This report describes the growth dynamics and compositional changes of SHaM embryos in response to change in the carbon to nitrogen ratio of the medium. It was postulated that at media compositions that were sufficient to support maximal growth rates, changes in the C:N ratio are ...


Computational Capabilities Of Leaky Integrate-And-Fire Neural Networks For Liquid State Machines, Amin Almassian, Christof Teuscher May 2013

Computational Capabilities Of Leaky Integrate-And-Fire Neural Networks For Liquid State Machines, Amin Almassian, Christof Teuscher

Student Research Symposium

We analyze the computational capability of Leaky Integrate-and-Fire (LIF) Neural Networks used as a reservoir (liquid) in the framework of Liquid State Machines (LSM). Maass et. al. investigated LIF neurons in LSM and their results showed that they are capable of noise-robust, parallel, and real-time computation. However, it still remains an open question how the network topology affects the computational capability of a reservoir. To address that question, we investigate the performance of the reservoir as a function of the average reservoir connectivity. We also show that the dynamics of the LIF reservoir is sensitive to changes in the average ...


Femtosecond Laser Patterned Templates And Imprinted Polymer Structures, Deepak Rajput May 2013

Femtosecond Laser Patterned Templates And Imprinted Polymer Structures, Deepak Rajput

Doctoral Dissertations

Femtosecond laser machining is a direct-write lithography technique by which user-defined patterns are efficiently and rapidly generated at the surface or within the bulk of transparent materials. When femtosecond laser machining is performed with tightly focused amplified pulses in single-pulse mode, transparent substrates like fused silica can be surface patterned with high aspect ratio (>10:1) and deep (>10 μm) nanoholes. The main objective behind this dissertation is to develop single-pulse amplified femtosecond laser machining into a novel technique for the production of fused silica templates with user-defined patterns made of high aspect ratio nanoholes. The size of the nanoholes ...


Controlling Bacterial Persister Cells With Low Level Electric Currents, Henry Lars Peterson May 2013

Controlling Bacterial Persister Cells With Low Level Electric Currents, Henry Lars Peterson

Syracuse University Honors Program Capstone Projects

Bacterial persister cells present a growing concern as they inherit the ability to tolerate high concentrations of antibiotics and repopulate after an antibiotic treatment leading to chronic diseases. Pseudomonas aeruginosa causes many human infections including skin infections and those associated with burn injuries, and implanted medical devices, and are associated with Cystic Fibrosis. Recently, the Ren Lab developed a novel approach to eliminate persister cells of P. aeruginosa, including those in biofilms, using low level electric currents. To evaluate the safety of this method and to better understand how the underlying elements, this study focused on the cytotoxicity of treatments ...


Cationic Starch Synthesis, Development, And Evaluation For Harvesting Microalgae For Wastewater Treatment, Renil John Anthony May 2013

Cationic Starch Synthesis, Development, And Evaluation For Harvesting Microalgae For Wastewater Treatment, Renil John Anthony

All Graduate Theses and Dissertations

In the quest for a feedstock for the production of biofuels, microalgae are showing potential. High photosynthetic efficiency, combined with high lipid content and low fresh water requirement, has contributed to the 'biofuels feedstock' status of microalgae. In some communities, microalgae have also been cultivated in wastewater in facultative lagoons to remove phosphorus and nitrogen through the growth of microalgae. With such systems in place, complete biological wastewater treatment can be achieved and the harvested microalgae could provide feedstock for biodiesel and various other bioproducts.

Due to small cell size, low culture concentrations, and the electrostatic repulsive forces that keep ...


Optimization Of Polyhydroxybutyrate Production In Recombinant Escherichia Coli Through Metabolic Modeling And Simulation, Yoshitaro Heshiki May 2013

Optimization Of Polyhydroxybutyrate Production In Recombinant Escherichia Coli Through Metabolic Modeling And Simulation, Yoshitaro Heshiki

All Graduate Plan B and other Reports

The objective of this study is to optimize the growth media and genes to maximize PHB production computer simulations, and to evaluate the simulation results through experiments. In order to achieve this objective, the metabolism of E. coli that produces PHB was modeled using the existing E. coli genome-scale metabolic networks. To identify the best additional nutrient for PHB production, carbon sources, minerals, amiano acids, nitrogen sources, and sulfur sources were examined by production potential analysis. Strain design was conducted to find the unwanted reactions to overexpress PHB synthesis pathway.


Elucidating Role Of Heart Valve Cells In The Aortic Valve Calcification, Mary Katherine Bailey, Adithi Amarnath Mar 2013

Elucidating Role Of Heart Valve Cells In The Aortic Valve Calcification, Mary Katherine Bailey, Adithi Amarnath

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

No abstract provided.


Atypical Glycolysis In Clostridium Thermocellum, Jilai Zhou, Daniel G. Olson, D. Aaron Argyros, Yu Deng, Walter M. Van Gulik, Johannes P. Van Dijken, Lee R. Lynd Feb 2013

Atypical Glycolysis In Clostridium Thermocellum, Jilai Zhou, Daniel G. Olson, D. Aaron Argyros, Yu Deng, Walter M. Van Gulik, Johannes P. Van Dijken, Lee R. Lynd

Open Dartmouth: Faculty Open Access Scholarship

Cofactor specificities of glycolytic enzymes in Clostridium thermocellum were studied with cellobiose-grown cells from batch cultures. Intracellular glucose was phosphorylated by glucokinase using GTP rather than ATP. Although phosphofructokinase typically uses ATP as a phosphoryl donor, we found only pyrophosphate (PPi)-linked activity. Phosphoglycerate kinase used both GDP and ADP as phosphoryl acceptors. In agreement with the absence of a pyruvate kinase sequence in the C. thermocellum genome, no activity of this enzyme could be detected. Also, the annotated pyruvate phosphate dikinase (ppdk) is not crucial for the generation of pyruvate from phosphoenolpyruvate (PEP), as deletion of the ppdk gene ...


Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Feb 2013

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same ...


A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud Jan 2013

A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud

Jonathan R. K. Stroud

No abstract provided.


Substrate Binding By The Catalytic Domain And Carbohydrate Binding Module Of Ruminococcus Flavefaciens Fd-1 Xyloglucanase/ Endoglucanase, Christopher D. Warner, Gulden Camci-Unal, Nicola L.B. Pohl, Clark Ford, Peter J. Reilly Jan 2013

Substrate Binding By The Catalytic Domain And Carbohydrate Binding Module Of Ruminococcus Flavefaciens Fd-1 Xyloglucanase/ Endoglucanase, Christopher D. Warner, Gulden Camci-Unal, Nicola L.B. Pohl, Clark Ford, Peter J. Reilly

Chemical and Biological Engineering Publications

Binding and thermodynamic properties of a carbohydrate binding module (CBM) and a glycoside hydrolase family 44 xyloglucanase/endoglucanase catalytic domain (CD) fromRuminococcus flavefaciens, both when separate and when linked to each other, have been quantified when binding various β-1,4-linked glucans and xylans. The three constructs bind cellotetraose, cellopentaose, and cellohexaose with association constants that increase with chain length. The CBM does not bind xylotetraose, xylopentaose, or xylohexaose. The CD appears to bind carboxymethylcellulose (CMC) and xylan only weakly, while the CBM and the CD/CBM bind them much more strongly than they bind the cellooligosaccharides. CMC is bound ...


Settling And Bioflocculation Of Two Species Of Algae Used In Wastewater Treatment And Algae Biomass Production, Derek Manheim, Yarrow M. Nelson Jan 2013

Settling And Bioflocculation Of Two Species Of Algae Used In Wastewater Treatment And Algae Biomass Production, Derek Manheim, Yarrow M. Nelson

Yarrow Nelson

The settling and bioflocculation of two strains of algae were investigated in the laboratory to provide insights to help improve algae settling in large-scale, algae-based wastewater treatment systems with simultaneous algae biofuel production. Energyefficient algae harvesting is a requirement for cost effective production of biofuels from algae, but algae harvesting usually requires energy-intensive methods such as centrifugation, filtration or dissolved air flotation. Bioflocculation using bacteriallyderived exudates is promising, but its use in high-rate algae pond (HRAP) wastewater systems has not yielded consistently reliable settling. To improve our understanding of the complex interactions between mixed cultures of algae and bacteria, the ...


Noninvasive Near-Infrared Diffuse Optical Monitoring Of Cerebral Hemodynamics And Autoregulation, Ran Cheng Jan 2013

Noninvasive Near-Infrared Diffuse Optical Monitoring Of Cerebral Hemodynamics And Autoregulation, Ran Cheng

Theses and Dissertations--Biomedical Engineering

Many cerebral diseases are associated with abnormal cerebral hemodynamics and impaired cerebral autoregulation (CA). CA is a mechanism to maintain cerebral blood flow (CBF) stable when mean arterial pressure (MAP) fluctuates. Evaluating these abnormalities requires direct measurements of cerebral hemodynamics and MAP. Several near-infrared diffuse optical instruments have been developed in our laboratory for hemodynamic measurements including near-infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS), hybrid NIRS/DCS, and dual-wavelength DCS flow-oximeter. We utilized these noninvasive technologies to quantify CBF and cerebral oxygenation in different populations under different physiological conditions/manipulations. A commercial finger plethysmograph was used to continuously monitor MAP ...


The Effects Of Hydrostatic Pressure On Early Endothelial Tubulogenic Processes, Ryan M. Underwood Jan 2013

The Effects Of Hydrostatic Pressure On Early Endothelial Tubulogenic Processes, Ryan M. Underwood

Theses and Dissertations--Biomedical Engineering

The effects of mechanical forces on endothelial cell function and behavior are well documented, but have not been fully characterized. Specifically, fluid pressure has been shown to elicit physical and chemical responses known to be involved in the initiation and progression of endothelial cell-mediated vascularization. Central to the process of vascularization is the formation of tube-like structures. This process—tubulogenesis—is essential to both the physiological and pathological growth of tissues. Given the known effects of pressure on endothelial cells and its ubiquitous presence in the vasculature, we investigated pressure as a magnitude-dependent parameter for the regulation of endothelial tubulogenic ...