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Molecular Characterization Of Antibiotic Resistant Shiga Toxin-Producing Escherichia Coli From Clinical And Food Samples, Khulud Alotaibi

Theses and Dissertations

Antimicrobial resistance (AMR) in foodborne pathogens can be a consequence of using antimicrobial drugs in food-producing animals. The emergence of antimicrobial resistance in foodborne pathogens is of great concern due to adverse patient health outcomes and the possibility of transferring genes encoding AMR to other clinically relevant pathogens. One of these bacteria is Shiga toxin-producing Escherichia coli (STEC), which can cause serious illness in humans for a haemolytic uremic syndrome (HUS). This study characterized and determined the mechanism of antibiotic resistance in 46 Shiga toxin-producing Escherichia coli strains collected by the U.S. Food and Drug Administration from food and clinical …

Crassostrea Gigas Invasion In Southern California: Macrofaunal Diversity And Local Community Impacts Of Ecosystem Engineers On Estuarine Habitats, Noah Jansen-Yee

Theses

Many marine ecosystems are facing the growing threat of biological invasions. These invasions can have a variety of different impacts on ecosystems and their inhabitants. The Pacific oyster, Crassostrea gigas, is currently in the relatively early stages of invasion in San Diego estuaries. Crassostrea gigas is a large, filter-feeding bivalve that forms dense oyster beds on hard substrate. These oysters are known to outcompete native counterparts and drastically alter habitats where they are present. Crassostrea gigas is an ecosystem engineer that, through shell creation and formation of a dense oyster matrix, impacts ecosystems in a variety of direct and indirect …

Health Expectations, Risk Tolerance, And Walking In Peripheral Artery Disease-Related Claudication, Sherene Sharath, Panos Kougias, Neal Barshes

Journal of Social, Behavioral, and Health Sciences

We examined the association between health expectations, baseline physical activity, and self-reported symptom severity among patients with claudication: calf pain that occurs during walking and is relieved at rest. Beliefs and attitudes toward exercise influence the behavior. When walking is prescribed as an alternative to surgical intervention with the intention of decreasing symptom severity, as is the case with claudication, it is important to assess patient perceptions, beliefs, and expectations. Through a phone survey, participants described the severity of their symptoms via the Walking Impairment Questionnaire. Data were collected on (1) health expectations and attitudes, assessments of value placed on …

Faculty Senate Agenda

Faculty Senate Agendas

No abstract provided.

Total Water Column Analysis Shows The Importance Of A Single Species In Subsurface Chlorophyll Maximum Thin Layers In Stratified Waters, Michelle L. Barnett, Alan E.S. Kemp, W. Alex M. Nimmo-Smith, Duncan A. Purdie

School of Biological and Marine Sciences

Marine phytoplankton form the base of marine food webs and are the driving force of the marine carbon cycle, so understanding the dynamics of their blooms is critical. While near-surface marine productivity (<10 m water depths) is extensively documented, that of the subsurface is less well characterised. Increasing evidence of the importance of subsurface chlorophyll maxima (SCM) and climatically driven increases in stratification of surface waters that promote SCM development call for improved sampling of the subsurface. To address this, we targeted the summer stratified waters of the Western English Channel, part of the NW European shelf seas, where SCM are commonly developed. In situ holography was applied to undertake the highest ever resolution, total water column, quantitative analysis of microplankton distribution, and demonstrated the importance of a SCM, co-located with the thermocline, dominated by a single species, the dinoflagellate Ceratium fusus. This species was dominant in the SCM over a wide area of the NW European shelf in the June/July 2015 study period and comprised up to 85% of the SCM biomass. Analysis of similarity and multivariate non-metric multidimensional scaling showed the phytoplankton community of the SCM to be statistically distinct from those of the surface and deep waters. Holography also revealed a fine scale layering of taxa at different levels within the SCM, likely reflecting ecological differences. Some taxa followed the peak abundance of C. fusus, while others reached maximum abundances immediately below or above the C. fusus maximum, suggesting the possible operation of exclusion mechanisms. Additionally, the detection of abundant aggregates located only within and beneath the SCM demonstrates the potential importance of this deep production for the export of carbon to the sea floor. Some predictions of phytoplankton productivity propose a shift to smaller cells in the more stratified oceans of the future resulting in declining production and export. Results presented here, however, contribute to a growing body of evidence that suggests, on the contrary, that key species among the larger celled/colonial, SCM-adapted diatoms and dinoflagellates may instead be selected in stratified conditions, driving increased production and export.

Review On Applications Of Lignin In Pavement Engineering: A Recent Survey, Hui Yao, Yiran Wang, Junfu Liu, Mei Xu, Pengrui Ma, Jie Ji, Zhanping You

Michigan Tech Publications, Part 1

Lignin is the second-largest plant polymer on Earth after cellulose. About 98% of lignin produced in the papermaking and pulping industry is used for combustion heating or power generation. Less than 2% of lignin is used in more valuable fields, mainly in the formulation of dispersants, adhesives, and surfactants. Asphalt is one of the most important materials in pavement engineering. It is a dark brown complex mixture composed of hydrocarbons with different molecular weights and their non-metallic derivatives. Because the chemical structure of lignin is similar to that of asphalt, it is a carbon-based hydrocarbon material. More researchers studied the …

Nipah Virus V Protein Binding Alters Mda5 Helicase Folding Dynamics, Nicole D Wagner, Hejun Liu, Henry W Rohrs, Gaya K Amarasinghe, Michael L Gross, Daisy W Leung

2020-Current year OA Pubs

Nipah virus (NiV) is an emerging and deadly zoonotic paramyxovirus that is responsible for periodic epidemics of acute respiratory illness and encephalitis in humans. Previous studies have shown that the NiV V protein antagonizes host antiviral immunity, but the molecular mechanism is incompletely understood. To address this gap, we biochemically characterized NiV V binding to the host pattern recognition receptor MDA5. We find that the C-terminal domain of NiV V (V

Impact Of Enclosures On Range Productivity In Chepareria West Pokot County Kenya, Regina W. Waiganjo, P. N. Mwangi, Rebecca H. Karanja

IGC Proceedings (1977-2023)

In the semi-arid areas of West Pokot particularly Chepareria, majority of the people live semi sedentary lives while others are nomadic pastoralists. In the last three decades, there have been concerted efforts to restore and improve rangeland in this area. Use of enclosures, which is one of the key interventions, by the Vi Agro- forestry a Non-Governmental Organisation, enhancing with many ecological processes such as disturbance, is a method of rehabilitating degraded rangeland, which in turn affects vegetation dynamics. Adoption of these strategies by farmers has been gradual and some areas are still open and degraded. The aim of this …

Increased Above-Ground Biomass And Plant Species Decline Related To The Presence Of Eragrostis Curvula Across Multiple Grazing Grasslands In The Snowy Monaro Region Of Australia, J. Brown, L. Ingram

IGC Proceedings (1977-2023)

"It will be noticed that invasions most often come to cultivated land, or to land much modified by human practice." This quote was published in 1958 by Charles Elton, and holds true today, backed by empirical evidence suggesting mechanisms of disturbance, plant functional traits and propagule pressure can push a cultivated system towards an invaded state. 17 farms, with either a current or previous history of grazing and land modification, within the Snowy Monaro Region, NSW, Australia, were surveyed to explore the relationship between the non-native C4 perennial tussock grass Eragrostis curvula [Schrad.] Nees. and species richness. As E. curvula …

The Use Of Open Communal Grazing Designs To Screen Options For Grazing Management, David R. Kemp, D. L. Michalk, P. M. Dowling, G. Millar

IGC Proceedings (1977-2023)

An open communal grazing design is described that enables a large number of grazing tactics to be concurrently evaluated in small plots under common grazing conditions. Pasture data indicated that the same level of utilisation occurred inside the experimental plots as in the surrounding field. However, differential grazing may occur where plots have divergent composition. The open communal design was economical using < 5% of the land, livestock and fencing resources of alternative designs. The limitations of the open communal design as a research tool are also discussed.

Stocking Rate And Supplementation Effects On Performance Of Lambs Grazing Triticale And Ryegrass Sward In Uruguay, R. San Julián, Fabio Montossi, L. Guarino, F. Pittaluga

IGC Proceedings (1977-2023)

An experiment was carried out from 9 June to 2 October 1997, using a Lolium multiflorum Lom. (Ryegrass) and X Triticosecale Wittmack (triticale) sward to evaluate the effect of stocking rate (SR; 20, 30 and 40 lambs/ha), and supplementation (S; with or without) on Corriedale lamb performance. SR had a significant effect on: liveweight gain (160, 130 and 90 g/an/d, P< 0.01); greasy fleece weight (2.8, 2.7 and 2.3 kg, P< 0.01); fiber diameter (28, 27, and 26 microns, P< 0.05); rib eye depth (2.4, 2.1 and 2.0 cm, P< 0.05); fat cover (3.2, 2.1 and 1.5 cm, P< 0.01); hot carcass weight (17.7, 15.6 and 13.5 kg/an, P< 0.01); GR (10.5, 6.6 and 4.2 mm, P< 0.01) and boneless leg weight (1.56, 1.42 and 1.24 kg, P< 0.05), for 20, 30 and 40 lambs per ha, respectively. At the highest SR, lambs increased grazing time (59 vs 52%) and biting rate (29 vs 26 bites/lamb/min). The mayor influence of S on lamb performance was found in grazing behavior variables: (grazing time (63 vs 50%, P< 0.01); biting rate (26.8 vs 28.4 bites/lamb/min, P< 0.01)), carcass characteristics: (hot carcass weight (15.3 vs 16.0 kg, P< 0.05); GR (7.9 and 6.3 mm, P< 0.05)) for with and without supplement, respectively. Over the experimental period (115 days), liveweight production and wool production ranged from 358 to 437 kg/ha for 20 and 30 lambs/ha respectively, and wool production from 55 to 93 kg/ha for 20 and 40 lambs/ha respectively. These results show the potential use of mixed ryegrass and triticale swards to produce high quality lamb meat even at high SRs, and the convenience of using supplements only when sward conditions are not sufficient to maintain an adequate lamb performance, particularly when high lamb SRs are used.

Lamb Stocking Rate And Supplementation Effects On Mixed Triticale And Ryegrass Swards Characteristics, R. San Julián, Fabio Montossi, L. Guarino, F. Pittaluga

IGC Proceedings (1977-2023)

An experiment was carried out from 9 June to 22 October 1997, using a Lolium multiflorum L. (ryegrass) and Triticosecale Wittmack (triticale) mixed sward grazed by lambs in a rotational grazing system, to determine the effect of stocking rate (SR; 20, 30 and 40 lambs/ha) and supplementation (S; with or without) on herbage production, composition and nutritive value. SR affected significantly before and after grazing herbage mass and sward height, being higher the values of these variables at the lower SR (3232, 2611 and 2345 kg DM ha^-1, P < 0.05; 2557, 1761 and 1612 kg DM ha^-1, P < 0.01; 17, 11 and 9 cm, P < 0.01 respectively). Increments in SR had an effect on post grazing sward composition, increasing the proportion of ryegrass (32, 36 and 47 %, P< 0.05) and decreasing triticale contribution (68, 64 and 55 %, P< 0.05) for 20, 30 and 40 lambs/ha. The effect of SR on sward nutritive value was not very clear. Before grazing, S affected significantly herbage mass, being higher the values at the supplemented treatments (2787 vs. 2672 kg DM ha^-1, P < 0.10). This experiment showed the high potential of forage production and nutritive value of ryegrass and triticale swards for lamb production in the sandy soil region of Uruguay, and the dominant effect of SR, compared to S, on most of the sward variables considered.

Invasive Plants For Commercial Use

Thomas Jefferson University Research Magazine

Invasive plants can have an array of negative ecological effects. In Northeast deciduous forests, for example, invasive plants outcompete natives, disrupt soil nutrient cycling and spread disease that affects humans as well as other plants.

“Invasives are creating increasingly difficult problems across the United States,” says Anne Bower, PhD, professor of biology. “While there are some public and nonprofit efforts to address those problems, we also need to employ free market incentives to overcome this major ecological challenge.” Dr. Bower, Mary Ann Wagner-Graham, PhD, assistant professor of biology, and Becky Flax, MS, assistant professor of textile design, have been working …

How Does Calcium Impact Cardiac Mitochondria?

Thomas Jefferson University Research Magazine

The ability of a cardiac cell to work hard and continuously depends on the energy-producing function of its mitochondria. Calcium is key to proper mitochondrial function—but only in the right amounts. Too much calcium leads to cell death; too little suppresses production of the fuel a cell needs to function.

Research collaborators Shey-Shing Sheu, PhD, professor of medicine, and Gyorgy Csordas, MD, research associate professor of pathology, anatomy and cell biology, are studying the mechanisms by which cardiac mitochondria use calcium and other molecules. And they are shedding light on how dysfunction in those mechanisms contribute to ischemic heart disease, …

Exploring Dna Damage Repair

Thomas Jefferson University Research Magazine

A cell’s ability to repair damaged DNA is key to its maintaining normal biology and protecting against cell death. But the repair process can be a two-sided coin: keeping a normal cell healthy is beneficial; keeping a malignant cell healthy can promote cancer. The mechanisms by which cells recognize and attempt to repair damage are myriad and complex; and individual DNA-repair proteins can be involved in multiple pathways. Jefferson researchers across several fields are working to understand the genomic and molecular processes at work in DNA repair—and the problems created when those processes go awry.

Reinvigorating Immune Response To Advanced Melanoma

Thomas Jefferson University Research Magazine

Melanoma represents a small fraction of skin cancerrelated malignancies, yet accounts for the majority of its mortalities—and the incidence of cutaneous melanoma is rising. While treatments using smalltargeted inhibitors and immune checkpoint antibodies have increased long-term survival in advancedstage cutaneous melanoma, many patients still do not realize any benefit from the treatments. Another group of patients initially have beneficial results but ultimately find their disease progressing, in part due to cancer cells’ acquired resistance to immune response. And still other patients have difficulty with the treatment’s high toxicity.

Emad Alnemri, PhD, Thomas Eakins Professor of Biochemistry and Molecular Biology, and …

Putting Light To Work

Thomas Jefferson University Research Magazine

Jefferson researchers are using light in new ways: using blue light to drive chemical processes, and creating products that illuminate in ultraviolet light. Their work reflects a convergence of disciplines such as physics, chemistry, textile engineering and nanotechnology that is driving applications with practical benefits for people and the environment.

John Milligan, PhD, assistant professor of chemical and biological sciences, is leading development of environmentally sustainable ways to spur chemical reactions using blue LED light. The work is an example of the “photoredox” subfield of organic chemistry, which has proven to be an increasingly effective method for building organic molecules. …

Architects Of A Sustainable Hemp Industry

Thomas Jefferson University Research Magazine

For centuries, the hemp plant has been recognized as a robust and renewable source of raw material for a host of purposes. However, for decades United States law conflated hemp with marijuana, and it fell out of use. Now, with such restrictions lifted, hemp has a bright future as a sustainable, high-value raw material for consumer and industrial products.

“Realizing that potential will require a lot of fundamental planning and development work, conceiving and establishing systems and platforms essential for building robust agricultural- and manufacturing-focused hemp industries,” says Ronald Kander, PhD, associate provost for applied research and dean of Kanbar …

Fast-Paced, Frontline Research

Thomas Jefferson University Research Magazine

While the clinicians of Jefferson Health were on the front lines of the battle with COVID-19— treating nearly 16,000 COVID patients and testing 35,000+ people—just behind them were the basic science researchers working hard to understand the molecular and cellular mechanisms driving the disease and the clinician-scientists working to adapt existing therapeutics to the unique challenges created by SARS-CoV-2.

Since early 2020, Jefferson researchers published more than 260 research studies on the coronavirus’s biology and on treatments

Covid’S Impact On Cancer Diagnosis

Thomas Jefferson University Research Magazine

While there are studies underway to characterize the direct effects of the COVID-19 pandemic on the care of patients with cancer, there have been relatively few quantitative reports of the impact that efforts to control the pandemic have had on the normal course of cancer diagnosis and treatment encounters. However, a multicenter research team led by Jack London, PhD, research professor emeritus of cancer biology, and Christopher McNair, PhD, associate director for data science at Sidney Kimmel Cancer Center and assistant professor of cancer biology, is studying that now. They have used encounter data from 20 healthcare institutions to compare …

Cryo-Em At Jefferson: Driving A New Era Of Scientific Discovery

Thomas Jefferson University Research Magazine

Scientific discovery is often the product of a delicate dance between intellectual insight and technological capabilities. It is a synergistic cycle of advancement where the desire to test a research hypothesis may motivate the creation of a new technology, and the new technical capacity yields unanticipated opportunities for wider discovery. And one of the most important drivers of new knowledge is the development of technologies for viewing biology’s fundamental building blocks: the atoms and molecules that comprise living cells.

Since late 2020, Jefferson researchers have been using one of the most powerful devices for “seeing” molecular structures at the atomic …

The Power Of Human Connection: Autism And The Suicide Risk, Rachel Barton

Intuition: The BYU Undergraduate Journal of Psychology

As researchers continue to understand autism spectrum disorder (ASD), one outstanding factor is causing concern within the psychological community: those with ASD are at a much higher risk of suicidal tendencies. These tendencies include suicidal ideation, attempting suicide, and death by suicide. Possible contributing factors to this increased risk include high levels of loneliness, pressure to conform to societal norms, as well as depression and anxiety. To decrease suicidality among the ASD population, further research is needed to fully understand why this behavior occurs at such a high percentage. Research is also needed to find appropriate and effective solutions to …

Reducing College Student Burnout: Predictive Factors, Harmful Effects, And Preventative Strategies, Eden Semu

Intuition: The BYU Undergraduate Journal of Psychology

Academic burnout is defined as experiencing emotional exhaustion, having cynical attitudes toward other people and one’s studies, and feeling unable to achieve one’s academic goals (Schaufeli et al., 2002b). Academic burnout has been observed among college student populations, and its prevalence is increasing as college students are more susceptible to psychological illness, are experiencing peak levels of life stress between ages 18 and 33, and are learning to handle novel demands associated with emerging adulthood (APA, 2012; NAMI , 2019). Internal factors, such as motivational style, attitude, and coping mechanisms, have been shown to mediate the relationship between demands and …

Infant Language Development: The Consequences Of Trauma, Janna Pickett

Intuition: The BYU Undergraduate Journal of Psychology

Infants between 0 and 36 months who experience physical and emotional trauma are at risk for severe social, emotional, cognitive, and physiological developmental deficits (Carpenter & Stacks, 2009; Jacobsen et al., 2013). As researchers search for protective factors against these deficits, productive language acquisition (the words an infant can verbally produce) has emerged as a potential predictor of resilience (Bellagamba et al., 2014; McCabe & Meller, 2004). This review proposes that infants who have acquired more advanced language, such as emotion descriptors, are able to define their experiences, learn how to respond to those experiences, and feel in control of …

The Double-Edged Sword: Unsuccessful Versus Successful Religious Parenting And Transmission, Avanlee Peterson

Intuition: The BYU Undergraduate Journal of Psychology

Religious participation can have many positive effects on children and adolescents, including improved health, academic, and social capabilities. Therefore, many parents are concerned by the decrease in religiosity in American society today. In response to this common concern, this literature review discusses how various types of religious parenting can improve parent-child religious transmission while maintaining good parent-child relationships and promoting healthy child development. Much of the research on parenting styles suggests that religious parenting is most successful when using an authoritative style of parenting (high structure, high warmth, high autonomy) rather than an authoritarian style (high structure, low warmth, low …

Powering Research On Mitochondrial Disease

Thomas Jefferson University Research Magazine

Mitochondria are specialized structures that exist in all cells except red blood cells. Generally known as the cell’s energy factory, mitochondria play a much broader role: from helping in the processes of making hemoglobin, detoxifying ammonia in the liver, metabolizing cholesterol and neurotransmitters and synthesizing estrogen and testosterone. Each year, thousands of children (and, increasingly, adults) are diagnosed with genetic mitochondrial conditions that range from skeletal muscle weakness and exercise intolerance to neurodegenerative diseases, heart disease and liver failure. In addition, mitochondria are increasingly recognized as playing a role in the pathology of diseases such as diabetes and cancer.

MitoCare …

The Joan & Joel Rosenbloom Center For Fibrotic Diseases

Thomas Jefferson University Research Magazine

Like cancer, fibrotic diseases are the result of complex biological processes that are similar in their final outcome, but diverse in the molecular mechanisms underlying those processes. Thus, identifying treatment targets and developing effective therapies is extremely difficult. It requires a continuous dialogue between basic scientists, translational researchers and clinical investigators across a range of disciplines.

The Joan & Joel Rosenbloom Center for Fibrotic Diseases, established in 2013, is an interdepartmental research program focusing on diagnosis, disease mechanisms, prevention and treatment of fibrotic diseases. It acts as a bridge: both to translate basic findings into drug therapies and to bring …

A Distinguished Career Honored - And The Work Continues

Thomas Jefferson University Research Magazine

The most prestigious award in international dermatology - the World Congress of Dermatology’s Alfred Marchionini Medal in Gold—is bestowed every four years, and in 2019, Jouni Uitto, MD, professor and chair of dermatology and cutaneous biology, was the humble recipient. The award is a recognition of Dr. Uitto’s long and distinguished career, in which he has published nearly 900 peerreviewed articles, textbook chapters and reviews— including 30 new publications over the past year.

Modeling The Systems Of Life

Thomas Jefferson University Research Magazine

Rajanikanth Vadigepalli, PhD, professor of pathology, anatomy and cell biology, is a chemical engineer and systems biologist who views the body as a series of systems nested within systems, interacting in dynamic ways. He and his colleagues use high-powered computers to create complex models of how tissues and organs function, which they compare to observations of in vitro and in vivo lab models. The iterative process enables them to find minute, molecular

Computational Medicine Center Uncovers New Rna Categories

Thomas Jefferson University Research Magazine

The interdisciplinary experts of Jefferson's Computational Medicine Center combine high-performance computing, data-driven hypothesis generation and wet laboratory work to unravel the biology and role of short RNA molecules with powerful regulatory roles. The Center’s research is led by Isidore Rigoutsos, PhD, Richard H. Hevner Professor of Computational Medicine; Yohei Kirino, associate professor of biochemistry and molecular biology; and Eric Londin, PhD, assistant professor of pathology, anatomy and cell biology.

The group has uncovered new RNA categories and many previously unsuspected molecules that act as regulators. They have also demonstrated that the identity and abundance of these newly discovered regulators depend …