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Theses/Dissertations

University of Massachusetts Amherst

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Full-Text Articles in Life Sciences

Cytochrome P450 Monooxygenase-Mediated Lipid Metabolism In Obesity And Colon Tumorigenesis, Weicang Wang Oct 2019

Cytochrome P450 Monooxygenase-Mediated Lipid Metabolism In Obesity And Colon Tumorigenesis, Weicang Wang

Doctoral Dissertations

Colon cancer is a major public health issue: it is expected to have 140,250 new cases and 50,630 deaths during 2018, making colon cancer the third most common type of cancer and the second leading cause of cancer death in the United States. Obesity is associated with enhanced colonic inflammation, which is a major risk factor of colorectal cancer. Currently, more than 35% of adults and nearly 17% of children are obese. Considering the obesity and colon cancer epidemic in the United States, there is an urgent need to identify novel therapeutic targets for obesity and colon cancer ...


Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao Oct 2019

Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao

Doctoral Dissertations

Mass spectrometry (MS) has played an increasingly prominent role in proteomics and structure biology because it shows superior capabilities in identification, quantification and structural characterization of proteins. To realize its full potential in protein analysis, significant progress has been made in developing innovative techniques and reagents that can couple to MS detection. This dissertation demonstrates the use of polymeric supramolecular assemblies for enhanced protein detection in complex biological mixtures by MS. An amphiphilic random co-polymer scaffold is developed to form functional supramolecular assemblies for protein/ peptide enrichment. The influences of charge density and functional group pKa on host-guest interactions ...


Factors Influencing Spartina Alterniflora Productivity In Relationship To Estuary Inlet Opening Ellisville Marsh, Plymouth, Ma, Ellen K. Russell Oct 2019

Factors Influencing Spartina Alterniflora Productivity In Relationship To Estuary Inlet Opening Ellisville Marsh, Plymouth, Ma, Ellen K. Russell

Doctoral Dissertations

A scientific basis for understanding the health of salt marsh vegetation, primarily Spartina alterniflora, in apposition to dredging of the tidal inlet to Ellisville Marsh in Plymouth, Massachusetts was determined. A three-hectare S. alterniflora loss, and coincident coastal bank erosion occurred; ostensibly due to inlet blockage from sand deposition, prolonged inundation, and meandering of inlet channel into coastal bank. This warranted dredging the tidal inlet, whereby tidal flushing would restore growth or discontinue die-off, and deter coastal bank erosion. A pre- and post dredge study was conducted assessing environmental factors related to plant productivity. Following dredging, an increase in tidal ...


Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu Oct 2019

Silver Mirror Substrate And Rolling Method For Improved Surface-Enhanced Raman Spesctroscopic Analysis In Food, Yanqi Qu

Doctoral Dissertations

Surface-enhanced Raman spectroscopy, short for SERS, is an emerging technology with great potential in food analysis due to rapid detection, high sensitivity, portable instrumentation, and simple sample preparation. However, it is always a bottleneck to obtain reproducible SERS measurements in real analytical cases due to the complicity of food systems and inhomogeneous aggregation of colloidal nanoparticles. To improve its performance for practical applications in food analysis, efforts have been made in improving the reproducibility, enhancing the selectivity and reducing the matrix interference to the analyte. Herein, a self-assembly silver nanoparticles mirror substrate was fabricated to improve the and the quantitative ...


Drivers And Consequences Of Carbon Use Efficiency - And Its Measurement In Soil, Grace Pold Oct 2019

Drivers And Consequences Of Carbon Use Efficiency - And Its Measurement In Soil, Grace Pold

Doctoral Dissertations

Soils serve as massive carbon sinks, but their ability to continue this ecological service is contingent on how the resident soil microbial community will respond to the ongoing climate crisis. One key dimension of the microbial response to warming is its carbon use efficiency (CUE), or the fraction of carbon taken up by an organism which is allocated to growth rather than respiration. However, the scientific community is still in the early stages of understanding the drivers, consequences - and even accurate measurements of - CUE. In this dissertation, I first quantified the variability of CUE and its responsiveness to temperature and ...


Effects Of Fertilization And Drying Conditions On The Quality Of Selected Chinese Medicinal Plants, Zoe Gardner Oct 2019

Effects Of Fertilization And Drying Conditions On The Quality Of Selected Chinese Medicinal Plants, Zoe Gardner

Doctoral Dissertations

Demand for Chinese medicinal herbs in the U.S. is increasing and American acupuncturists and farmers are interested in domestic production of these plants. Little is known about the feasibility of production of these species outside of China. Four species of herbs were selected for cultivation trials. The purposes of this research were to evaluate the feasibility of cultivation of these species in the northeastern United States, to develop basic agronomic data for each species, and to determine the effects of nitrogen fertilizer on plant growth, yield, and secondary metabolites. Agastache rugosa, Schizonepeta tenuifolia, Leonurus japonicus, and Leonurus sibiricus were ...


Function And Dissipation In Finite State Automata - From Computing To Intelligence And Back, Natesh Ganesh Oct 2019

Function And Dissipation In Finite State Automata - From Computing To Intelligence And Back, Natesh Ganesh

Doctoral Dissertations

Society has benefited from the technological revolution and the tremendous growth in computing powered by Moore's law. However, we are fast approaching the ultimate physical limits in terms of both device sizes and the associated energy dissipation. It is important to characterize these limits in a physically grounded and implementation-agnostic manner, in order to capture the fundamental energy dissipation costs associated with performing computing operations with classical information in nano-scale quantum systems. It is also necessary to identify and understand the effect of quantum in-distinguishability, noise, and device variability on these dissipation limits. Identifying these parameters is crucial to ...


Improving Chinese Mothers’ Health Literacy: A Wechat Intervention, Qiong Chen Oct 2019

Improving Chinese Mothers’ Health Literacy: A Wechat Intervention, Qiong Chen

Doctoral Dissertations

The health literacy and eHealth literacy of women during the reproductive age is crucial, as it can affect their health and the health of their children. Promoting health literacy is essential to achieve mothers’ empowerment by improving access to and capacity of using health information effectively. However, functional, interactive, and critical health literacy and eHealth literacy have never been assessed among Chinese women.

The first study during this dissertation assessed functional, interactive, and critical health literacy and eHealth literacy among 421 of Chinese mothers with children under 3 years old. The results revealed overall less than optimal level of health ...


Multi-Level Barriers To Art Adherence Among Hiv-Infected Women In Rural Eswatini: A Mixed Methods Approach, Nozipho Becker Oct 2019

Multi-Level Barriers To Art Adherence Among Hiv-Infected Women In Rural Eswatini: A Mixed Methods Approach, Nozipho Becker

Doctoral Dissertations

Eswatini has the highest global prevalence of HIV despite universal access to free treatment. Lack of compliance continues to be a significant challenge for HIV care and management programs throughout the country. Studies investigating barriers to antiretroviral therapy (ART) adherence, particularly in women, who are the most vulnerable to HIV infections, are limited. The disproportionate impact of HIV on women can be attributed to multiple risk factors at the individual, household, and community/structural levels. Women living in rural settings are particularly at risk as a result of socio-cultural and environmental vulnerabilities such as oppressive traditional practices, intimate partner violence ...


Ecology Of The Elusive: Genome-Informed Investigation Of Soil Microbial Diversity, Lauren Alteio Oct 2019

Ecology Of The Elusive: Genome-Informed Investigation Of Soil Microbial Diversity, Lauren Alteio

Doctoral Dissertations

Soil is considered one of the most diverse ecosystems on Earth, harboring diversity of organisms across the three domains of life. It is spatially and chemically heterogeneous: properties that intertwine in a complex matrix to support organismal diversity and function across different scales. Soil microorganisms both respond to and drive changes in ecosystems through metabolic activities. A single gram of soil is teeming with millions of cells comprised of thousands of species. Much of this diversity remains uncharacterized due to technical and methodological challenges faced by soil ecologists. Due to the complex physicochemical properties of soil and cross-feeding interactions between ...


An Examination Of Tern Diet In A Changing Gulf Of Maine, Keenan Yakola Oct 2019

An Examination Of Tern Diet In A Changing Gulf Of Maine, Keenan Yakola

Masters Theses

The Gulf of Maine is a dynamic ecosystem with rapidly warming sea surface temperatures (SSTs), therefore it is vital to understand how species interactions vary over time and space. In chapter two, I quantify and compare dietary differences among four tern species, across seven islands in the region, over a 32-year period. Multivariate statistical analyses were employed to discern spatial and temporal differences in foraging ecology. Findings suggest there are significant differences between species and islands; however, only three prey species comprise the majority of chick diet for all terns and islands. The reliance on only a few prey items ...


Investigating The Role Of Lbh During Early Embryonic Development In Xenopus Laevis, Emma Weir Oct 2019

Investigating The Role Of Lbh During Early Embryonic Development In Xenopus Laevis, Emma Weir

Masters Theses

LBH is a highly conserved protein whose role during vertebrate development is relatively under-studied. In collaboration with the Albertson lab, our lab has previously shown that it is necessary for cranial neural crest cell migration in the zebrafish and in Xenopus laevis. The molecular mechanisms through which it acts are not well understood.

In Xenopus, LBH is a maternally deposited protein. As such, studying its role in early development has not been feasible through the morpholino-mediated knockdown techniques that prevent translation of target genes. Recently, a technique for degrading endogenous proteins was developed, called Trim-Away. This was developed in mammalian ...


The Effects Of Acidosis On Calcium Dependent Binding Of A Single Crossbridge, Matthew Unger Oct 2019

The Effects Of Acidosis On Calcium Dependent Binding Of A Single Crossbridge, Matthew Unger

Masters Theses

Intracellular acidosis is a putative agent of skeletal muscle fatigue, in part, because acidosis depresses the calcium (Ca2+) sensitivity and force production of muscle (18, 50). However, the molecular mechanisms behind this depression in Ca2+ sensitivity and force production are unknown. This gap in knowledge poses a significant challenge in generating a complete understanding of the fatigue process. To close this gap, the ability of myosin to bind to a single actin filament was measured under acidic conditions, in a laser trap assay, with and without regulatory proteins. Decreasing pH from 7.4 to 6.5 reduced the ...


Arboriculture Safety Around The World, Jamie Lim Oct 2019

Arboriculture Safety Around The World, Jamie Lim

Masters Theses

Arboricultural work is inherently dangerous, with more serious injuries and fatalities than most other professions. Safety standards exist in some jurisdictions, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) jurisdictions share standards. To establish a baseline understanding of these issues, my objectives were to (i) develop a database of existing standards, (ii) identify the most frequently occurring safety topics and (iii) describe similarities and differences in safety topics among standards from different countries. I worked with a variety of contacts and traditional university library resources to identify, obtain, analyze ...


The Efficacy Of Atp Monitoring Devices At Measuring Organic Matter On Postharvest Surfaces, Kristin Lane Oct 2019

The Efficacy Of Atp Monitoring Devices At Measuring Organic Matter On Postharvest Surfaces, Kristin Lane

Masters Theses

The Food Safety Modernization Act (FSMA), specifically the Produce Safety Rule (PSR), requires growers to clean and sanitize food-contact surfaces to protect against produce contamination. The ATP monitoring device is a potential sanitation tool to monitor the efficacy of an on-farm cleaning and sanitation program that could help growers meet regulatory expectations mandated by PSR. The ATP device uses bioluminescence to detect all ATP (found in bacteria and produce matter cells) from a swabbed surface. Little work has been done to test the efficacy of these tools under postharvest conditions. The present study evaluated ATP measurement for postharvest surface cleanliness ...


Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel Oct 2019

Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel

Masters Theses

In order to ascertain the degree of compatibility in developmental restructuring and behavioral plasticity between two fish species frequently made subject of laboratory research (Metriaclima zebra & Danio rerio), alternative trophic niche exposure experiments utilizing novel three-prong feeding treatments were conducted to obtain morphometric data, which demonstrated both species do bear some degree of plasticity. The results are somewhat complicated by differences in locality of detectable restructuring, which may be due to disparity in the form-function relationship for each species’ lineage. Each is notable in the manner of respective species’ jaw protrusion, as it is driven by anterior kinethmoid rotation in ...


Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo Oct 2019

Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo

Masters Theses

With the growing concern of the accumulation of plastic-based food packaging waste, the search for bio-based biodegradable packages is on the rise. These materials differ from their petro-based counterparts in their degradation rates, which are much higher in the former. Not only do bio-based biodegradable materials degrade faster during post-usage processes but also they age faster during usage and storage, which affects their performance and functionality. The application of noninvasive testing methods with the capability to report on the matrix’s state could assist in the development of a more ubiquitous way to assess ageing in food packaging, particularly in ...


Determining Kinetic Parameters Of Thiamine Degradation In Three Nasa Spaceflight Foods In Thermal Processing And Long-Term Storage And Methods For Analyzing Microstructure And Precipitant Development In Real And Model Wines, Timothy R. Goulette Jul 2019

Determining Kinetic Parameters Of Thiamine Degradation In Three Nasa Spaceflight Foods In Thermal Processing And Long-Term Storage And Methods For Analyzing Microstructure And Precipitant Development In Real And Model Wines, Timothy R. Goulette

Doctoral Dissertations

The current NASA spaceflight food program encompasses a wide variety of commercial and custom-made edible products. These foods are designed to ensure each crewmember receives the Recommended Dietary Allowance (RDA) of vitamins and minerals to maintain adequate health during the entire spaceflight mission. With the desire for long-duration and exploration-class missions, such as the impending mission to Mars, the retention of important nutrients such as labile vitamins in spaceflight foods is critically important. For this reason, multiple studies were conducted to determine the vitamin degradation behavior of thiamine (vitamin B1) within three spaceflight foods which demonstrated both significant presence ...


Physical And Biological Drivers Of Juvenile Fish Distributions In Unstructured Shallow Tropical Nearshore Habitats, Christopher Haak Jul 2019

Physical And Biological Drivers Of Juvenile Fish Distributions In Unstructured Shallow Tropical Nearshore Habitats, Christopher Haak

Doctoral Dissertations

The structural complexity of aquatic habitats can influence the ecological processes that occur within them, as fine-scale topographic features act as refugia for small fishes, buffering the effects of environmental stressors. Accordingly, the habitat requirements of juvenile demersal fishes in shallow littoral zones are often defined by their associations with distinct benthic microhabitats, such as densely vegetated substrates. However, an array of ecologically-important juvenile fishes also associate with topographically-homogeneous, sparsely-vegetated substrata. Absent the benefits offered by structural refugia, such fishes may be more affected by environmental variability and may have evolved distinct strategies for coping with stressors. I examined this ...


Walking For Object Transport: An Examination Of The Coordinative Adaptations To Locomotor, Perceptual, And Manual Task Constraints, Avelino Amado Jul 2019

Walking For Object Transport: An Examination Of The Coordinative Adaptations To Locomotor, Perceptual, And Manual Task Constraints, Avelino Amado

Doctoral Dissertations

The goal of this dissertation was to understand how the intrinsic dynamics of gait adapt to support the performance of an ecologically relevant object transport task. A common object transport task is walking with a cup of water. Because the water can move relatively independent of the cup, the cup and water system is classified as a complex object. To model this task participants carried a cup with a wooden lid placed on top. On the lid there was a circular region with the same circumference as the cup and a ball. The object of the task was to keep ...


Metabolic Cost And Stability Of Locomotion In People With Lower Limb Amputation, Ryan Wedge Jul 2019

Metabolic Cost And Stability Of Locomotion In People With Lower Limb Amputation, Ryan Wedge

Doctoral Dissertations

It is generally accepted that metabolic energy expenditure and gait stability are key factors that influence the selection of able-bodied locomotor patterns. It is unclear how energy expenditure and gait stability are prioritized during walking in people with lower limb amputation. People with lower limb amputation generally have greater metabolic energy expenditure during walking and increased incidence of falls. People with unilateral lower limb amputation spend more time on the intact limb compared with the prosthetic limb, while able-bodied individuals generally walk with symmetrical timing between limbs. Restoring symmetry is often a goal of rehabilitation and assistive devices, yet the ...


Multiscale Simulations Of Intrinsically Disordered Proteins, Xiaorong Liu Jul 2019

Multiscale Simulations Of Intrinsically Disordered Proteins, Xiaorong Liu

Doctoral Dissertations

Intrinsically disordered proteins (IDPs) lack stable secondary and/or tertiary structures under physiological conditions. The have now been recognized to play important roles in numerous biological processes, particularly cellular signaling and regulation. Mutation of IDPs are frequently associated with human diseases, such as cancers and neuron degenerative diseases. Therefore, it is important to understand the structure, dynamics, and interactions of IDPs, so as to establish the mechanistic basis of how intrinsic disorder mediates versatile functions and how such mechanisms may fail in human diseases. However, the heterogeneous structural ensembles of IDPs are not amenable to high resolution characterization solely through ...


Acute Estrogen Synthesis And Action In The Auditory Cortex Of Developing Male Zebra Finches (Taeniopygia Guttata), Daniel Vahaba Jul 2019

Acute Estrogen Synthesis And Action In The Auditory Cortex Of Developing Male Zebra Finches (Taeniopygia Guttata), Daniel Vahaba

Doctoral Dissertations

Birdsong, as with human speech, is learned during an age- and experience-dependent sensitive period early in life. Songbirds must first memorize their parents’ song during a sensory phase, then refine their own burgeoning vocalizations to match the auditory memory of their parents’ song during a sensorimotor phase. While the error-correction aspect of the sensorimotor phase of song learning is comparatively well understood, it is largely unknown how auditory memories are formed and how auditory processing may change across development to facilitate song memorization. The songbird caudomedial nidopallium (NCM) is a brain region that encodes complex communication signals like song and ...


Feasibility And Efficacy Of A Recess-Based Combined Fitness Intervention On Cognition And Academic Performance In Elementary School Children, Christine St Laurent Jul 2019

Feasibility And Efficacy Of A Recess-Based Combined Fitness Intervention On Cognition And Academic Performance In Elementary School Children, Christine St Laurent

Doctoral Dissertations

Youth physical activity and fitness have been reported to influence cognition and academic related outcomes. Despite the potential benefits of muscular fitness, few intervention studies have examined the impact of an intervention that has incorporated both cardiorespiratory and muscular fitness training on cognition and academic performance in children. Previous studies have mainly been implemented either during the school day or immediately after-school. Although recess may be an ideal time to promote physical activity because it does not compete with other academic demands, it has been an understudied setting. Therefore, the purpose of this dissertation project was to examine the feasibility ...


The Spatial Organization Of Mycobacterial Membrane, Julia Puffal Jul 2019

The Spatial Organization Of Mycobacterial Membrane, Julia Puffal

Doctoral Dissertations

Mycobacteria comprises a large group of organisms including the pathogenic species Mycobacterium tuberculosis, the causative agent of tuberculosis. A fast- growing saprophytic member of this genus, however, Mycobacterium smegmatis, is oftentimes used as a model organism for the pathogenic species. With a unique cell envelope architecture and unconventional polar growth, spatial coordination of cell envelope biosynthesis is vital for proper assembly of this complex structure. Here, we provide a comprehensive overview of known lateral heterogeneities in mycobacterial plasma membrane, with a particular focus on the intracellular membrane domain (IMD), a spatially distinct region of the plasma membrane with diverse functions ...


Tropomyosin-Based Effects Of Acidosis On Thin-Filament Regulation During Muscle Fatigue, Brent Scott Jul 2019

Tropomyosin-Based Effects Of Acidosis On Thin-Filament Regulation During Muscle Fatigue, Brent Scott

Masters Theses

Skeletal muscle fatigue is defined as a loss in the force/velocity generating capacity of a muscle. A portion of the loss in function is attributable to effects of acidosis (i.e. low pH) on the regulatory proteins, troponin and tropomyosin (Tm), which regulate the binding of myosin and actin in a calcium (Ca++) dependent manner. However, the relative role of troponin and Tm on myosin-actin function during acidosis is not clear, nor are the mechanisms underlying these effects. PURPOSE: To determine the role of Tm in the acidosis-induced depression of muscle function using isolated muscle proteins in an in ...


Changes In Color Guidance Over The Course Of A Complex Visual Search, Ryan Papargiris Jul 2019

Changes In Color Guidance Over The Course Of A Complex Visual Search, Ryan Papargiris

Masters Theses

When searching for an object, we store a mental representation of the target, which guides our search through the use of attention. The effectiveness of this search guidance varies depending on the task and the relationship between target and distractors. With a better understanding of how search guidance changes over time within a trial, we can better compare the differences between experimental conditions. Eye tracking data from a variety of search tasks were analyzed to determine how color guidance varied over the course of the trial. Color guidance for a given fixation was evaluated based on the distance in color ...


Development And Cross-Validation Of A Cadence-Based Metabolic Equation For Walking, Christopher C. Moore Jul 2019

Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney Jul 2019

Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney

Masters Theses

Trees provide countless environmental, economic, and societal benefits to the urban environment, and may become increasingly important to maintaining environmental quality and human well-being in the face of increasing urbanization and climate change. However, trees in these urban areas are rapidly diminishing across the United States. Much of this loss can be prevented with proper planning and management, focused on selecting tree species that are both well-suited to the area’s growing conditions and able to survive the many stress factors in an urban setting. Choosing which tree species to plant in Massachusetts is especially challenging considering the lack of ...


The Efficacy Of Nanoemulsion-Based Delivery Systems To Improve Vitamin D3 Bioaccessibility And Bioavailability, Alagu Selvi Kadappan Jul 2019

The Efficacy Of Nanoemulsion-Based Delivery Systems To Improve Vitamin D3 Bioaccessibility And Bioavailability, Alagu Selvi Kadappan

Masters Theses

Vitamin D deficiency is an epidemic issue in all age groups in Western countries and that affects both skeletal and non-skeletal functions. Even with the wide application of food fortification, vitamin D deficiency tends to increase continuously. Being hydrophobic in nature, vitamin D has poor solubility; thereby it negatively affects its absorption and bioavailability when compared to other hydrophilic dietary compounds. The need to develop a novel strategy is of greater importance to enhance its bioavailability and thereby improving vitamin D level in the body.

In this study, lipid-based delivery of oil-in-water nanoemulsion (diameter < 200nm) was utilized to improve the bioaccessibility and oral bioavailability of vitamin D3. First, we examined the in ...