Digital Commons Network^™

Why Do Antibiotics Exist?, Fabrizio Spagnolo, Monica Trujillo, John J. Dennehy

Publications and Research

In the struggle with antibiotic resistance, we are losing. There is now a serious threat of moving into a postantibiotic world. High levels of resistance, in terms of both frequency and strength, have evolved against all clinically approved antibiotics worldwide. The usable life span of new clinically approved antibiotics is typically less than a decade before resistance reaches frequencies so high as to require only guarded usage. However, microbes have produced antibiotics for millennia without resistance becoming an existential issue. If resistance is the inevitable consequence of antibiotic usage, as has been the human experience, why has it not become …

Potential Solar Replacement Of Hydroelectricity To Reopen Rivers: Maine As A Case Example, Shailesh Sharma, John Waldman

Publications and Research

Hydroelectricity provides 6% of U.S. electrical power needs, but hydro-dams also cause environmental harm, including the retardation or complete blockage of spawning runs of anadromous fishes. To facilitate fish movements, engineered-fishways have long been used but many have performed poorly. Dam-removal is the most effective way of restoring dwindling migratory fish populations by allowing unrestricted pathways to their spawning areas and for the downstream migrations of post-spawning adults and juveniles. However, removals of hydro-dams result in a loss of electricity production. For the replacement of energy foregone from hydro-dam removals, various alternative energy installations are now feasible. We present one-to-one …

Fundamentals Of Interpersonal Communication, Teresa Fisher

Open Educational Resources

This textbook introduces students to fundamentals of interpersonal communication. It begins with a foundational chapter about communication including models of, definitions for, basic principles of, a focus on interpersonal communication, and the impact of social media on communication. It continues with chapters exploring various facets of interpersonal communication: intercultural communication, the self and communication, perception, verbal, nonverbal, and listening. The final two chapters look at interpersonal relationships and communication as well as conflict in interpersonal communication.

The Political Imagination: Introduction To American Government, Peter Kolozi, James E. Freeman

Open Educational Resources

The Political Imagination: Introduction to American Government provides realistic, critical analysis as well as a hopeful, engagement-oriented narrative that encourages students to understand the important role they can play in the political system and in crafting a society in which they want to live. The Political Imagination draws on social and political theory and history offering an analytical as well as normative framework to think about the substance of politics, the procedures and institutions of government, and a dynamic, socially contingent definition of political power.

Cloning And Characterization Of The Vasopressin-Oxytocin Neuropeptide Signaling System In The Vocal Control System Of The Zebra Finch (Taeniopygia Guttata), Emily R. Tortora

Dissertations and Theses

Vasopressin (VP) and Oxytocin (OT) are neuropeptides produced in the hypothalamus and expressed in the cerebrum and pituitary gland of the brain. Studies of VP and OT have long demonstrated their influence on social behaviors in mammals. Comparative analyses of these neuropeptides and in-depth analyses in non-mammalian species may reveal the specific mechanistic roles these hormones play in social behavioral functioning. The acquisition of complex behavioral patterns involves sensory-motor functions. How social interactions modulate sensory-motor mechanisms that promote complex behavior acquisition and maintenance can be well study in vocal learning birds. Here, in addition to reviewing the pertinent literature, I …

There’S More Than One Way To Beat The Heat: What Anal Probes Reveal About Thermal Responses In Neotropical Beetles (Coleoptera: Cerambycidae)., Emilie I. Dion

Dissertations and Theses

Increasing global temperatures have been linked to shifts in the distributions and preferred microhabitats of terrestrial species. This trend is predicted to impact tropical forest insects, which may already be exposed to conditions that bring them close to their thermal maxima. Tropical microhabitats are linked to vertical stratification, because the canopy is hotter, winder, and less humid than the ground. In ectothermic organisms, such as beetles, thermoregulation is dependent on morphological and behavioral traits. This study investigates woodboring cerambycid beetles, to determine how behavioral thermoregulation through microhabitat selection (vertical stratification) is correlated to morphological attributes (color lightness, size, and pubescence) …

Osteocyte Activity And Skeletal Muscle Relative Gene Expression Profiling After Short-Term Muscle Paralysis, Michelle Gelbs

Dissertations and Theses

Mechanical loading is essential for maintaining bone tissue. Reduced mechanical loading has been shown to have a negative effect on bone, and can result in the development of disuse osteoporosis. Disuse models of muscle inactivity and immobilization, like the Botox model used in this study, result in changes in the bone microarchitecture, the mechanisms behind which are not fully understood. In a previous four-week Botox disuse study, skeletally mature 20- week-old rats experienced degradation of intracortical bone, increased vascular porosity, and decreased osteocyte lacunar density in the tibiae. The focus of this study was to explicate a potential source of …

Development Of An Injectable Methylcellulose Hydrogel System For Nucleus Pulposus Repair And Regeneration, Nada A. Haq-Siddiqi

Dissertations and Theses

Low back pain is the most common cause of disability in the world and is often caused by degeneration or injury of the intervertebral disc (IVD). The IVD is a complex, fibrocartilaginous tissue that allows for the wide range of spinal mobility. Disc degeneration is a progressive condition believed to begin in the central, gelatinous nucleus pulposus (NP) region of the tissue, for which there are few preventative therapies. Current therapeutic strategies include pain management and exercise, or surgical intervention such as spinal fusion, none of which address the underlying cause of degeneration. With an increasingly aging population, the socioeconomic …

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …

Spatial And Non-Spatial Patterns Of Genetic Diversity In Neotropical Bats, Andrea J. Calderon Brito

Dissertations and Theses

Macroecological studies that predict genetic diversity and its correlation with other biodiversity dimensions are essential to conservation in a rapidly changing environment. However, in bats (order Chiroptera), studies associating abiotic or ecological traits that could help to predict genetic diversity are scarce, even for singular species. In the Neotropics, the highest concentration of mammal and amphibian genetic diversity has been found in the Andes mountains and the Amazon Rainforest, yet it is an open question whether bat genetic diversity is also higher in these regions, or even if any abiotic factors are correlated with bat genetic diversity. Additionally, it is …

‘A Contradiction In Essence’: Eroticism And The Creation Of The Self In Henry Miller, Cian Doyle

Dissertations and Theses

The intention of this paper is, in the first, to demonstrate that Miller’s work has been labeled ‘erotic’, and that this obscures the true contribution of his work – but that as much as it obscures his work, this label also provides us an avenue to access it. In the second, it is to explore what actually constitutes the ‘erotic’, how this is featured in Miller’s work, and how it functions as an analytic tool to reveal what is significant in that work. Lastly, with specific regard to the works Tropic of Cancer and Tropic of Capricorn, the intention …

Restoration Of Bone Material And Microstructural Properties After Long-Term Remodeling Suppression, Abigail A. Coffman

Dissertations and Theses

Anti-resorptive drugs, principally bisphosphonates (BPs), are the mainstay of osteoporosis treatment. They work by inhibiting bone resorption/remodeling, thus preventing bone loss. However, long-term suppression of bone resorption adversely affects bone tissue mechanical properties, even while conserving bone mass. Lack of remodeling leads to accumulation of fatigue-induced microdamage, altered matrix mineralization and reduction in normal bone tissue heterogeneity, causing impaired strength and fracture toughness. The most severe consequence to patients, while rare, is Atypical Femur Fractures (i.e., complete fatigue fractures of the femoral shaft). To counteract the effects of long-term remodeling suppression, a temporary break in BP treatment (a "drug holiday) …

A New Mathematical Theory For The Dynamics Of Large Tumor Populations, A Potential Mechanism For Cancer Dormancy & Recurrence And Experimental Observation Of Melanoma Progression In Zebrafish, Adeyinka A. Lesi

Dissertations and Theses

Cancer, a family of over a hundred disease varieties, results in 600,000 deaths in the U.S. alone. Yet, improvements in imaging technology to detect disease earlier, pharmaceutical developments to shrink or eliminate tumors, and modeling of biological interactions to guide treatment have prevented millions of deaths. Cancer patients with initially similar disease can experience vastly different outcomes, including sustained recovery, refractory disease or, remarkably, recurrence years after apparently successful treatment. The current understanding of such recurrences is that they depend on the random occurrence of critical mutations. Clearly, these biological changes appear to be sufficient for recurrence, but are they …

Disaster And Hope In The Comic Universe Of 'Gardening In The Tropics', Molly Mosher

Dissertations and Theses

In this paper, I explore ideas of dominion and how Western canon has helped propagate ideas of human domination of the natural world. Using Joseph W. Meeker’s The Comedy of Survival, I trace a line from the advent of the literary tragedy to the climate crisis. To contrast, I use his idea of comedy as the antidote to domination — a way of thinking that might inspire collaboration with the natural world. I will explore the comic with, predominately, Olive Senior’s Gardening in the Tropics, alongside Jamaica Kincaid’s gardening studies and Mona Lisa Saloy’s essay on environmental destruction. To …

Roberto Bolaño’S 2666, The Funneling Effect Of Capitalism, And The Production, Consumption, And Proliferation Of Violence For Profit, John Timlin

Dissertations and Theses

Roberto Bolaño's novel 2666 is a realist text, one that reflects the simple fact that in contemporary capitalism, the physical destruction of female bodies is a profitable enterprise; one that forces its readers to confront their complicity or outright participation in violence against women; and one that relates directly to violence against women as consumable entertainment in American mass culture.

Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla

Dissertations and Theses

Parasitoid wasps are effective biological control agents that have evolved intricate host immune suppression strategies to overcome host immune defenses. The most important anti-parasite defense mechanism is encapsulation, where the host’s blood cells surround the wasp egg. In the Drosophila/Leptopilina host-parasitoid system, extracellular vesicles (EVs) are oviposited along with the wasp egg. The EVs possess spikes and contain hundreds of proteins, some of which enable wasp eggs to escape encapsulation by changing the morphology and function of hemocytes, or killing them. Previous studies have identified an abundant surface/spike protein (SSp40) from Leptopilina heterotoma EVs. While p40, a predicted …

Analyzing Ultrastructural Characteristics Of Post-Synaptic Targets Of Pre-Identified Presynaptic Boutons In Layer 3 And Layer 4 Of The Ferret Primary Visual Cortex, Donia Shehab

Dissertations and Theses

The purpose of this study was to analyze the size and ultrastructural characteristics of post-synaptic elements apposed to previously characterized pre-synaptic elements in layers 3 and 4 of the primary visual cortex (PVC). We are aiming to quantify a range of values for synaptic element morphologies as well as to correlate pre- and post-synaptic elements to find a set of rules that is prevalent in the visual cortex that can also be upheld in other mammals. We hypothesize that bigger pre-synaptic elements correlate to bigger synapses and bigger post-synaptic elements. We compared these two different layers because they receive synaptic …

Reassessing The Ranging Behavior Of Black-And-White Ruffed Lemurs (Varecia Variegata) In Ranomafana National Park, Madagascar, Jelisa R. Oliveras

Dissertations and Theses

This study investigates black-and-white ruffed lemur (Varecia variegata) space use and movement using autocorrelated kernel density estimation (AKDE), a new methodology available from the continuous-time movement model (ctmm) package in R. Data were collected from 24 adults and subadults (10 males, 11 females, 3 subadult males) living in two adjacent V. variegata communities at Mangevo bush camp in Ranomafana National Park, Madagascar (RNP) for 11 months (February – December 2008) to estimate annual and seasonal patterns of individual and community-level range use. Autocorrelated kernel density estimates generated in this study are compared to earlier kernel density estimates from …

The Impact Of The International Monetary Fund’S 2016 – 2019 Loan To Egypt On The Country’S Development, Anasimon Takla

Dissertations and Theses

The primary objective of the International Monetary Fund (IMF) is growth. The organization and its programs can enable the development of nations across the globe and stimulate growth. However, due to weaknesses in its system with conditions that are offered as blanket solutions for unique problems as well as unequal bargaining terms, the IMF can exacerbate the situation in nations that are already suffering with crises. Following years of unrest after the Arab Spring, Egypt finds itself in an unwieldly position having both vowed to increasing its development as well as introduced major reforms based on IMF recommendations in order …

When The Brain Plays A Game: Neural Responses To Visual Dynamics During Naturalistic Visual Tasks, Jason Ki

Dissertations and Theses

Many day-to-day tasks involve processing of complex visual information in a continuous stream. While much of our knowledge on visual processing has been established from reductionist approaches in lab-controlled settings, very little is known about the processing of complex dynamic stimuli experienced in everyday scenarios. Traditional investigations employ event-related paradigms that involve presentation of simple stimuli at select locations in visual space and discrete moments in time. In contrast, visual stimuli in real-life are highly dynamic, spatially-heterogeneous, and semantically rich. Moreover, traditional experiments impose unnatural task constraints (e.g., inhibited saccades), thus, it is unclear whether theories developed under the reductionist …

Teaching Authors About Predatory Journals In The One-On-One Consultation, Monica Berger

Publications and Research

This recipe guides academic librarians through author consultations related to predatory or questionable publishers. Lists of predatory journals provide quick answers to questions but leave authors in the dark. The focus of the consultation is to closely examine negative and positive indicators for a specific journal. Although it is valuable for authors to learn the signals of predatory journals, it is equally if not more important to emphasize tools like Think.Check.Submit that stimulate critical and analytical thinking about publishing choices. The consultation will result in a more empowered and scholarly information literate colleague and provides opportunities to introduce authors to …

The Relationships Between Spawning Horseshoe Crabs And Egg Densities: Recommendations For The Assessment Of Populations And Habitat Suitability, Mark L. Botton Phd, Christina P. Colon Phd, Matthew Sclafani Phd, Robert E. Loveland Phd, Susan Elbin Phd, Kaitlyn Parkins

Publications and Research

1. Horseshoe crab population sizes and trends have been previously studied using surveys of spawning adults and counts of eggs from surface (top 5 cm) and deep (20 cm) sediment samples. The correlations between surface and deep eggs were studied at two locations, Delaware Bay and Jamaica Bay, USA, and the correlations between egg densities and spawning counts were examined in Jamaica Bay. 2. There were significantly higher densities of eggs in deep sediments than in surface sediments. Only about 10% of the variability in surface egg density was explained by deep egg density. The numerical patterns between surface and …

Lives In Musicology: My Life In Writings, Kofi Agawu

Publications and Research

Responding to an invitation from the editors of Acta Musicologica to tell the story of his life in musicology, Kofi Agawu describes his upbringing and early education in Ghana and his university studies in the UK and the US. In a career focused on teaching, research, and writing, he outlines a number of intellectual projects involving the analysis of African and European music. He ends by acknowledging renewed discussions of race and identity in the musical academy today, and hints at his own growing interest in African art music.

The Uncanny Swipe Drive: The Return Of A Racist Mode Of Algorithmic Thought On Dating Apps, Gregory Narr

Publications and Research

As algorithmic media amplify longstanding social oppression, they also seek to colonize every last bit of sociality where that oppression could be resisted. Swipe apps constitute prototypical examples of this dynamic. By employing protocols that foster absent-minded engagement, they allow unconscious racial preferences to be expressed without troubling users’ perceptions of themselves as non-racist. These preferences are then measured by recommender systems that treat “attractiveness” as a zero-sum game, allocate affective flows according to the winners and losers of those games, and ultimately amplify the salience of race as a factor of success for finding intimacy. In thus priming users …

Human Retinal Organoids Release Extracellular Vesicles That Regulate Gene Expression In Target Human Retinal Progenitor Cells, Jing Zhou, Miguel Flores‑Bellver, Jianbo Pan, Alberto Benito‑Martin, Cui Shi, Onyekwere Onwumere, Jason Mighty, Jiang Qian, Xiufeng Zhong, Tasmim Hogue, Baffour Amponsah‑Antwi, Linda Einbond, Rajendra Gharbaran, Hao Wu, Bo‑Juen Chen, Zhiliang Zheng, Tatyana Tchaikovskaya, Xusheng Zhang, Hector Peinado, Maria Valeria Canto‑Soler, Stephen Redenti

Publications and Research

The mechanisms underlying retinal development have not been completely elucidated. Extracellular vesicles (EVs) are novel essential mediators of cell‑to‑cell communication with emerging roles in developmental processes. Nevertheless, the identification of EVs in human retinal tissue, characterization of their cargo, and analysis of their potential role in retina development has not been accomplished. Three‑dimensional retinal tissue derived from human induced pluripotent stem cells (hiPSC) provide an ideal developmental system to achieve this goal. Here we report that hiPSC‑derived retinal organoids release exosomes and microvesicles with small noncoding RNA cargo. EV miRNA cargo‑predicted targetome correlates with Gene Ontology (GO) pathways involved in …

The Atr-Chek1 Pathway Inhibits Axon Regeneration In Response To Piezo-Dependent Mechanosensation, Feng Li, Tsz Y. Lo, Leann Miles, Qin Wang, Harun N. Noristani, Dan Li, Jingwen Niu, Shannon Trombley, Jessica I. Goldshteyn, Chuxi Wang, Shuchao Wang, Jingyun Qiu, Katarzyna Pogoda, Kalpana Mandal, Megan Brewster, Panteleimon Rompolas, Ye He, Pau A. Janmey, Gareth M. Thomas, Shuxin Li, Yuanquan Song

Advanced Science Research Center

Atr is a serine/threonine kinase, known to sense single-stranded DNA breaks and activate the DNA damage checkpoint by phosphorylating Chek1, which inhibits Cdc25, causing cell cycle arrest. This pathway has not been implicated in neuroregeneration. We show that in Drosophila sensory neurons removing Atr or Chek1, or overexpressing Cdc25 promotes regeneration, whereas Atr or Chek1 overexpression, or Cdc25 knockdown impedes regeneration. Inhibiting the Atr-associated checkpoint complex in neurons promotes regeneration and improves synapse/behavioral recovery after CNS injury. Independent of DNA damage, Atr responds to the mechanical stimulus elicited during regeneration, via the mechanosensitive ion channel Piezo and its downstream NO …

Vulnerable And Resilient Phenotypes In A Mouse Model Of Anorexia Nervosa, Jeff A. Beeler, Devry Mourra, Roseanna M. Zanca, Abigail Kalmbach, Celia Gellman, Benjamin Y. Klein, Rebecca Ravenelle, Peter Serrano, Holly Moore, Stephen Rayport, Susana Mingote, Nesha Burghard

Advanced Science Research Center

Background

Increased physical activity is a common feature of anorexia nervosa (AN). Although high activity levels are associated with greater risk of developing AN, particularly when combined with dieting, most individuals who diet and exercise maintain a healthy body weight. It is unclear why some individuals develop AN while most do not. A rodent model of resilience and vulnerability to AN would be valuable to research. Dopamine, which is believed to play a crucial role in AN, regulates both reward and activity and may modulate vulnerability.

Methods

Adolescent and young adult female C57BL/6N mice were tested in the activity-based anorexia …

Proximal And Distal Effects Of Genetic Susceptibility To Multiple Sclerosis On The T Cell Epigenome, Tina Roostaei, Hans-Ulrich Klein, Yiyi Ma, Daniel Felsky, Pia Kivisäkk, Sarah M. Connor, Alexandra Kroshilina, Christina Yung, Belinda J. Kaskow, Xiaorong Shao, Brooke Rhead, José M. Ordovás, Devin M. Absher, Donna K. Arnett, Jia Liu, Nikolaos Patsopoulos, Lisa F. Barcellos, Howard L. Weiner, Philip L. De Jager

Advanced Science Research Center

Identifying the effects of genetic variation on the epigenome in disease-relevant cell types can help advance our understanding of the first molecular contributions of genetic susceptibility to disease onset. Here, we establish a genome-wide map of DNA methylation quantitative trait loci in CD4⁺ T-cells isolated from multiple sclerosis patients. Utilizing this map in a colocalization analysis, we identify 19 loci where the same haplotype drives both multiple sclerosis susceptibility and local DNA methylation. We also identify two distant methylation effects of multiple sclerosis susceptibility loci: a chromosome 16 locus affects PRDM8 methylation (a chromosome 4 region not previously associated …

Brain-Specific Lipoprotein Receptors Interact With Astrocyte Derived Apolipoprotein And Mediate Neuron-Glia Lipid Shuttling, Jun Yin, Emma Spillman, Ethan S. Cheng, Jacob Short, Yang Chen, Jingce Lei, Mary Gibbs, Justin S. Rosenthal, Chengyu Sheng, Yuki X. Chen, Kelly Veerasammy, Tenzin Choetso, Rinat Abzalimov, Bei Wang, Chun Han, Ye He, Quan Yuan

Advanced Science Research Center

Lipid shuttling between neurons and glia contributes to the development, function, and stress responses of the nervous system. To understand how a neuron acquires its lipid supply from specific lipoproteins and their receptors, we perform combined genetic, transcriptome, and biochemical analyses in the developing Drosophila larval brain. Here we report, the astrocyte-derived secreted lipocalin Glial Lazarillo (GLaz), a homolog of human Apolipoprotein D (APOD), and its neuronal receptor, the brain-specific short isoforms of Drosophila lipophorin receptor 1 (LpR1-short), cooperatively mediate neuron-glia lipid shuttling and support dendrite morphogenesis. The isoform specificity of LpR1 defines its distribution, binding partners, and ability to …

Potential Ecological Impacts Of Climate Intervention By Reflecting Sunlight To Cool Earth, Phoebe L. Zarnetske, Jessica Gurevitch, Janet Franklin, Peter M. Groffman, Cheryl S. Harrison, Jessica J. Hellmann, Forrest M. Hoffman, Shan Kothari, Alan Robock, Simone Tilmes, Daniele Visioni, Jin Wu, Lili Xia, Cheng-En Yang

Advanced Science Research Center

As the effects of anthropogenic climate change become more severe, several approaches for deliberate climate intervention to reduce or stabilize Earth’s surface temperature have been proposed. Solar radiation modification (SRM) is one potential approach to partially counteract anthropogenic warming by reflecting a small proportion of the incoming solar radiation to increase Earth’s albedo. While climate science research has focused on the predicted climate effects of SRM, almost no studies have investigated the impacts that SRM would have on ecological systems. The impacts and risks posed by SRM would vary by implementation scenario, anthropogenic climate effects, geographic region, and by ecosystem, …