Digital Commons Network^™

Dynamics Of Coupled Noisy Neural Oscillators With Heterogeneous Phase Resetting Curves, Cheng Ly

Statistical Sciences and Operations Research Publications

Pulse-coupled phase oscillators have been utilized in a variety of contexts. Motivated by neuroscience, we study a network of pulse-coupled phase oscillators receiving independent and correlated noise. An additional physiological attribute, heterogeneity, is incorporated in the phase resetting curve (PRC), which is a vital entity for modeling the biophysical dynamics of oscillators. An accurate probability density or mean field description is large dimensional, requiring reduction methods for tractability. We present a reduction method to capture the pairwise synchrony via the probability density of the phase differences, and explore the robustness of the method. We find the reduced methods can capture …

Clinical Features And Genetic Analysis Of 20 Chinese Patients With X-Linked Hyper-Igm Syndrome, Lin-Lin Wang, Wei Zhou, Wei Zhao, Zhi-Qing Tian, Wei-Fan Wang, Xiao-Fang Wang, Tong-Xin Chen

Pediatrics Publications

X-linked hyper-IgM syndrome (XHIGM) is one type of primary immunodeficiency diseases, resulting from defects in the CD40 ligand/CD40 signaling pathways. We retrospectively analyzed the clinical and molecular features of 20 Chinese patients diagnosed and followed up in hospitals affiliated to Shanghai Jiao Tong University School of Medicine from 1999 to 2013. The median onset age of these patients was 8.5 months (range: 20 days–21 months). Half of them had positive family histories, with a shorter diagnosis lag. The most common symptoms were recurrent sinopulmonary infections (18 patients, 90%), neutropenia (14 patients, 70%), oral ulcer (13 patients, 65%), and protracted diarrhea …

Metabolic Effects Of Acute Thiamine Depletion Are Reversed By Rapamycin In Breast And Leukemia Cells, Shuqian Liu, Sumitra Miriyala, Mignon A. Keaton, Craig T. Jordan, Christina Wiedl, Daret K. St. Clair, Jeffrey A. Moscow

Pediatrics Publications

Thiamine-dependent enzymes (TDEs) control metabolic pathways that are frequently altered in cancer and therefore present cancer-relevant targets. We have previously shown that the recombinant enzyme thiaminase cleaves and depletes intracellular thiamine, has growth inhibitory activity against leukemia and breast cancer cell lines, and that its growth inhibitory effects were reversed in leukemia cell lines by rapamycin. Now, we first show further evidence of thiaminase therapeutic potential by demonstrating its activity against breast and leukemia xenografts, and against a primary leukemia xenograft. We therefore further explored the metabolic effects of thiaminase in combination with rapamycin in leukemia and breast cell lines. …

Life2cl N (N = 4–6) Clusters: Double-Exchange Mediated Molecular Magnets, Kalpataru Pradhan, Purusottam Jena

Physics Publications

A systematic study of LiFe2Cl n (n = 4–6) clusters, based on gradient corrected density functional theory (DFT), shows that the electron contributed by Li can transform antiferromagnetic Fe2Cl n(n = 4 and 6) clusters into ferromagnetic clusters. In Fe2Cl6 (Fe2Cl4) cluster, the Fe atoms in +3 (+2) oxidation states are aligned antiferromagnetically, consistent with the super-exchange model. The extra electron from Li atom creates a charge disproportionation in the LiFe2Cl6(LiFe2Cl4) cluster that mediates the double-exchange interaction between the Fe atoms.Antiferromagnetic to ferromagnetic transition can also be induced by hole doping as seen to be the case with Fe2Cl5 which …

Why Is Low Waist-To-Chest Ratio Attractive In Males? The Mediating Roles Of Perceived Dominance, Fitness, And Protection Ability, Anthony E. Coy, Jeffrey D. Green, Michael E. Price

Psychology Publications

Past research suggests that a lower waist-to-chest ratio (WCR) in men (i.e., narrower waist and broader chest) is viewed as attractive by women. However, little work has directly examined why low WCRs are preferred. The current work merged insights from theory and past research to develop a model examining perceived dominance, fitness, and protection ability as mediators of to WCR-attractiveness relationship. These mediators and their link to both short-term (sexual) and long-term (relational) attractiveness were simultaneously tested by having 151 women rate one of 15 avatars, created from 3D body scans. Men with lower WCR were perceived as more physically …

Parental Strain, Mental Health Problems, And Parenting Practices: A Longitudinal Study, Alicia Borre, Wendy L. Kliewer

Psychology Publications

Although poor parenting practices place youth living in under resourced communities at heightened risk for adjustment difficulties, less is known about what influences parenting practices in those communities. The present study examines prospective linkages between three latent constructs: parental strain, mental health problems and parenting practices. Parental victimization by community violence and life stressors were indicative of parental strain; depressive, anxious, and hostile symptoms were indicators of parental mental health; and parental knowledge of their child’s activities and child disclosure were indicators of parenting practices. Interviews were conducted annually for 3 waves with 316 female caregivers (92% African American) parenting …

Near-Infrared Imaging Of Adoptive Immune Cell Therapy In Breast Cancer Model Using Cell Membrane Labeling, Fatma M. Youniss, Gobalakrishnan Sundaresan, Laura J. Graham, Li Wang, Collin R. Berry, Gajanan K. Dewkar, Purnima Jose, Harry D. Bear, Jamal Zweit

Radiology Publications

The overall objective of this study is to non-invasively image and assess tumor targeting and retention of directly labeled T-lymphocytes following their adoptive transfer in mice. T-lymphocytes obtained from draining lymph nodes of 4T1 (murine breast cancer cell) sensitized BALB/C mice were activated in-vitro with Bryostatin/Ionomycin for 18 hours, and were grown in the presence of Interleukin-2 for 6 days. T-lymphocytes were then directly labeled with 1,1-dioctadecyltetramethyl indotricarbocyanine Iodide (DiR), a lipophilic near infrared fluorescent dye that labels the cell membrane. Assays for viability, proliferation, and function of labeled T-lymphocytes showed that they were unaffected by DiR labeling. The DiR …

Multifunctional Skin-Like Electronics For Quantitative, Clinical Monitoring Of Cutaneous Wound Healing, Yoshiaki Hattori, Leo Falgout, Woosik Lee, Sung-Young Jung, Emily Poon, Jung Woo Lee, Ilyoun Na, Amelia Geisler, Divya Sadhwani, Yihui Zhang, Yewang Su, Xiaoqi Wang, Zhuangjian Liu, Jing Xia, Huanyu Cheng, R. Chad Webb, Andrew P. Bonifas, Philip Won, Jae-Woong Jeong, Kyung-In Jang, Young Min Song, Beatrice Nardone, Michael Nodzenski, Jonathan A. Fan, Yonggang Huang, Dennis P. West, Amy S. Paller, Murad Alam, Woon-Hong Yeo, John. A. Rogers

Mechanical and Nuclear Engineering Publications

Non-invasive, biomedical devices have the potential to provide important, quantitative data for the assessment of skin diseases and wound healing. Traditional methods either rely on qualitative visual and tactile judgments of a professional and/or data obtained using instrumentation with forms that do not readily allow intimate integration with sensitive skin near a wound site. Here, an electronic sensor platform that can softly and reversibly laminate perilesionally at wounds to provide highly accurate, quantitative data of relevance to the management of surgical wound healing is reported. Clinical studies on patients using thermal sensors and actuators in fractal layouts provide precise time-dependent …

Art In The Age Of Networks - Networks As A Way Of Thinking, Rabeya Jalil

Higher Education Resources

The theme-based and material-based units (with lessons and lesson sequences) propose a curriculum for one academic semester in an undergraduate visual arts school (for sophomore, 2nd year, or junior, 3rd year students). However the lessons could be modified and tailored to any age group developmentally. This curricular framework aims to foster collaboration (within individuals, materials and disciplines), explore networked pedagogy and networks in pedagogy as a collaborating force through and with the visual arts and explore the materiality of the code and the digital media. The course also engages with new media theory and literature, investigates the materiality of the …

Rock Inhibitor Is Not Required For Embryoid Body Formation From Singularized Human Embryonic Stem Cells, Giuseppe Pettinato, Wendy S. Vanden Berg-Foels, Ning Zhang, Xuejun Wen

Chemical and Life Science Engineering Publications

We report a technology to form human embryoid bodies (hEBs) from singularized human embryonic stem cells (hESCs) without the use of the p160 rho-associated coiled-coil kinase inhibitor (ROCKi) or centrifugation (spin). hEB formation was tested under four conditions: +ROCKi/+spin, +ROCKi/-spin, -ROCKi/+spin, and -ROCKi/-spin. Cell suspensions of BG01V/hOG and H9 hESC lines were pipetted into non-adherent hydrogel substrates containing defined microwell arrays. hEBs of consistent size and spherical geometry can be formed in each of the four conditions, including the -ROCKi/-spin condition. The hEBs formed under the -ROCKi/-spin condition differentiated to develop the three embryonic germ layers and tissues derived from …

Excellence In Community-Engaged Research At Virginia Commonwealth University: A Compendium Of Case Studies Developed Through A Faculty Learning Community, Division Of Community Engagement, Center For Clinical And Translational Research

Community-Engaged Research Resources

Since 2005, the Center for Teaching Excellence (CTE) at VCU has offered faculty learning communities (FLC) on a variety of teaching and learning issues. For 2013-2014, VCU's Division of Community Engagement, Center for Clinical and Translational Research, and Center for Teaching Excellence collaborated to offer the first FLC focused on community-engaged research (CEnR). This FLC included 9 faculty members who are or who had been engaged in complex research projects that intentionally connect the campus and community. The members represented a wide range of disciplines, including education, social work, arts, public health, cancer prevention and control, psychology, family medicine, nutritional …

Associations Between Childhood Body Size, Composition, Blood Pressure And Adult Cardiac Structure: The Fels Longitudinal Study, Roy T. Sabo, Miao-Shan Yen, Stephen Daniels, Shumei S. Sun

Biostatistics Publications

Objectives

To determine whether childhood body size, composition and blood pressure are associated with adult cardiac structure by estimating childhood “age of divergence.”

Methods

385 female and 312 male participants in the Fels Longitudinal Study had echocardiographic measurements of left ventricular mass, relative wall thickness, and interventricular septal thickness. Also available were anthropometric measurements of body mass index, waist circumference, percentage body fat, fat free mass, total body fat, and systolic and diastolic blood pressures, taken in both childhood and adulthood. The age of divergence is estimated as the lowest age at which childhood measurements are significantly different between patients …

We Are Not Hiding So Why Can't You Find Us? Attracting Users To Special Collections & Archives, Margaret T. Kidd, Elizabeth Mcdaniel

VCU Libraries Faculty and Staff Presentations

Special Collections & Archives have become the focal point for many research libraries due to the unique materials. However, there are still many faculty and students who are unaware of the potential research value of these collections. This session explores strategies to improve awareness and use.

Informationist Supplement: A Collaboration To Improve Collaboration, Julie Arendt, Martha Roseberry

VCU Libraries Faculty and Staff Presentations

Four librarians at Virginia Commonwealth University teamed up with faculty in mathematics and biomedical engineering to receive an NIH informationist administrative supplement. The supplement supports a research team developing a mathematical model of ventilator-induced lung inflammation. Our goals are to develop workflow strategies to enhance team communication, provide information and data management services, assist with dissemination of the research results, and assess the impact of the grant. We are currently examining the team’s workflow to find data management and communication gaps and are evaluating tools for group annotation and sharing of articles and references.

Examining A Link Between Paraquat, Alpha-Synuclein Fibrillation And Neurodegeneration: A Review, Nikhil Ailaney

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Parkinson’s disease is a chronic and progressive motor system disorder that is caused by the degeneration of dopaminergic neurons in the central nervous system. At the molecular level, Parkinson’s disease works by decreasing the concentrations of the neurotransmitter dopamine, a chemical messenger involved in motor messaging, within the central nervous system. Low levels of dopamine in the central nervous system causes motor system dysfunction because the insufficient levels of dopamine lead to an inability for neurons to successfully transmit motor messages. At the organismal level, Parkinson’s disease causes tremors, Bradykinesia, and rigidity. These symptoms ultimately lead to a diminished quality …

Understanding Nicotine Addition: Dependency As A Result Of Maladaptive Brain Structure, Nate Thomas

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Nicotine addiction is the most prevalent, destructive dependency found in our culture. Despite its well-documented damaging health risks, nicotine use is still widely accepted and could be conceptualized as a social epidemic. Much of this acceptance may stem from nicotine’s lack of debilitating cognitive effects, as compared to those of other abused drugs. However, what may reign dominantly over nicotine’s legality is simple cultural precedent: tobacco has never been illegal and holds a place in human history. Therefore, attempting to alter this would prove highly unpopular and unsuccessful. This macroscopic irrationality, a blind favor for cultural precedents, parallels the irrational …

Typologies Of Black Male Sensitivity In R&B And Hip Hop, Cassandra Chaney, Krista D. Mincey

Journal of Hip Hop Studies

A qualitative content analysis was conducted on the lyrics of 79 R&B and Hip Hop songs from 1956-2013 to identify the ways that these Black male artists expressed sensitivity. The songs were determined by Billboard Chart Research Services, and Phenomenology provided the theoretical foundation on which the themes were identified. Qualitative analysis of the lyrics revealed Black male sensitivity in R&B and Hip Hop to be based on the following four typologies: (a) Private Sensitivity; (b) Partnered Sensitivity; (c) Perceptive Sensitivity; and (d) Public Sensitivity. Private Sensitivity occurred when the Black male is alone; feels lonely; disguises or hides his …

Vcu's Green Richmond Research, Nadia Rentia

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

The impact of urbanization on the dogwood tree was the VCU junior Kaitlyn Parkman’s focus as she researched hundreds of trees in Richmond.

Selective Activation Of Htrpv1 By N-Geranyl Cyclopropylcarboxamide, An Amiloride-Insensitive Salt Taste Enhancer, Min Jung Kim, Hee Jin Son, Yiseul Kim, Hae-Jin Kweon, Byung-Chang Suh, Vijay Lyall, Mee-Ra Rhyu

Physiology and Biophysics Publications and Presentations

TRPV1t, a variant of the transient receptor potential vanilloid-1 (TRPV1) has been proposed as a constitutively active, non-selective cation channel as a putative amiloride-insensitive salt taste receptor and shares many properties with TRPV1. Based on our previous chorda tympani taste nerve recordings in rodents and human sensory evaluations, we proposed that N-geranylcyclopropylcarboxamide (NGCC), a novel synthetic compound, acts as a salt taste enhancer by modulating the amiloride/benzamil-insensitive Na+ entry pathways. As an extension of this work, we investigated NGCC-induced human TRPV1 (hTRPV1) activation using a Ca2+-flux signaling assay in cultured cells. NGCC enhanced Ca2+ influx in hTRPV1-expressing cells in …

Lack Of Negatively Charged Residues At The External Mouth Of Kir2.2 Channels Enable The Voltage-Dependent Block By External Mg2+, Junwei Li, Xiaoxiao Xie, Jun Liu, Hui Yu, Suhua Zhang, Yong Zhan, Hailin Zhang, Diomedes E. Logothetis, Hailong An

Physiology and Biophysics Publications and Presentations

Kir channels display voltage-dependent block by cytosolic cations such as Mg2+ and polyamines that causes inward rectification. In fact, cations can regulate K channel activity from both the extracellular and intracellular sides. Previous studies have provided insight into the up-regulation of Kir channel activity by extracellular K+ concentration. In contrast, extracellular Mg2+ has been found to reduce the amplitude of the single-channel current at milimolar concentrations. However, little is known about the molecular mechanism of Kir channel blockade by external Mg2+ and the relationship between the Mg2+ blockade and activity potentiation by permeant K+ ions. In this study, we applied …

Suppression Of The Pi3k Pathway In Vivo Reduces Cystitis-Induced Bladder Hypertrophy And Restores Bladder Capacity Examined By Magnetic Resonance Imaging, Zhongwei Qiao, Chunmei Xia, Shanwei Shen, Frank D. Corwin, Miao Liu, Ruijuan Guan, John R. Grider, Li-Ya Qiao

Physiology and Biophysics Publications and Presentations

This study utilized magnetic resonance imaging (MRI) to monitor the real-time status of the urinary bladder in normal and diseased states following cyclophosphamide (CYP)-induced cystitis, and also examined the role of the phosphoinositide 3-kinase (PI3K) pathway in the regulation of urinary bladder hypertrophy in vivo. Our results showed that under MRI visualization the urinary bladder wall was significantly thickened at 8 h and 48 h post CYP injection. The intravesical volume of the urinary bladder was also markedly reduced. Treatment of the cystitis animals with a specific PI3K inhibitor LY294002 reduced cystitis-induced bladder wall thickening and enlarged the intravesical volumes. …

Voltage Sensing Mechanism In The Voltage-Gated And Proton (H+)-Selective Ion Channel Hv1, Aaron L. Randolph

Theses and Dissertations

Activation of the intrinsic aqueous water-wire proton conductance (GAQ) in Hv1 channels is controlled by changes in membrane potential and the transmembrane pH gradient (ΔpH). The mechanism by which changes in ΔpH affect the apparent voltage dependence of GAQ activation is not understood. In order to measure voltage sensor (VS) activation in Hv1, we mutated a conserved Arg residue in the fourth helical segment (S4) to His and measured H+ currents under whole-cell voltage clamp in transfected HEK-293 cells. Consistent with previous studies in VS domain containing proteins, we find that Hv1 R205H mediates a robust resting-state H+ ‘shuttle’ conductance …

A Model Of The Effect Of Uncertainty On The C Elegans L2/L2d Decision, Leon Avery

Physiology and Biophysics Publications and Presentations

Abstract

At the end of the first larval stage, the C elegans larva chooses between two developmental pathways, an L2 committed to reproductive development and an L2d, which has the option of undergoing reproductive development or entering the dauer diapause. I develop a quantitative model of this choice using mathematical tools developed for pricing financial options. The model predicts that the optimal decision must take into account not only the expected potential for reproductive growth, but also the uncertainty in that expected potential. Because the L2d has more flexibility than the L2, it is favored in unpredictable environments. I estimate …

Where Does Electronic Aggression Fit?: A Comparison Of Dimensional And Categorical Models Of Adolescent Aggression, Krista R. Mehari

Theses and Dissertations

Electronic aggression is a rapidly growing focus of research, but it lacks a unifying theoretical framework that is necessary to advance the field. The lack of a theoretical framework has led to inconsistencies in measurement of electronic aggression, making it difficult to draw conclusions across studies. In general, researchers have assumed that electronic aggression constitutes a new form of aggression, a counterpart to physical, verbal, and relational aggression, due to unique features surrounding the perpetration of electronic aggression. Furthermore, researchers have treated electronic aggression as a categorical variable based on the assumption that “cyberbullies” constitute a distinct group of adolescents. …

The Effect Of Youth Diabetes Self-Efficacy On The Relation Among Family Conflict, Disease Care And Glycemic Control, Kathryn Maher

Theses and Dissertations

The aim of the current study was to examine the associations among youth diabetes self-efficacy, family conflict, disease care and glycemic control via a comprehensive path model. Data were from a baseline assessment of a longitudinal RCT of 257 adolescent/parent dyads (adolescents aged 11–14). Each member of the dyad separately completed the Self-efficacy for Diabetes Self-Management Scale, Family Environment Conflict subscale, Diabetes Family Conflict Scale, Diabetes Behavior Rating Scale, and 24-hr Diabetes Interview Blood Glucose Frequency subscale. Additionally, a biological marker of glycemic control, or HbA1c, and relevant demographic variables were collected. A mediation model found higher youth diabetes self-efficacy …

Assessing Design Thinking Through The Activation Of A Social Challenge In Higher Education: An Academic Inquiry, Amin Matni

Theses and Dissertations

This thesis is an inquiry that documents, identifies and assesses the effectiveness, circumstances, and potential resources related to addressing the gap between social needs and higher education as stated in the National Development Strategy 2011-2016. The aim of the thesis is to evaluate the response of the students on the collaborative, human-centered, result-oriented aspects of design thinking while addressing the eating experience topic, an articulated theme from the wicked problem of obesity. The eating experience theme provided students from design, business and engineering majors a contextualized topic to test design thinking in a series of workshops conducted in three different …

Treatment-Induced Breast Cancer Dormancy And Relapse, Rebecca Keim

Theses and Dissertations

When breast tumor cells encounter stress due to cancer therapies, they may enter a dormant state, escaping from treatment-induced apoptosis. Dormant cells may eventually regain proliferative capabilities and cause recurrent metastatic disease, which is the leading cause of mortality in breast cancer patients. We sought to determine if a high dose of radiation therapy (RT) or combined chemo-immunotherapy, with and without the blockade of autophagy by chloroquine (CQ), could overcome treatment-induced tumor dormancy or relapse. We found that autophagy contributes in part to treatment-induced tumor dormancy. We also found that three therapeutic strategies were successful in inhibiting or preventing tumor …

Fathering And Child Maltreatment: A Grounded Theory Study, Jennifer Shadik

Theses and Dissertations

Literature related to fathers and child physical abuse and neglect is lacking (Guterman & Lee, 2005; Lee, Bellamy, & Guterman, 2009). The purpose of this study was to better understand several pertinent aspects of fathering related to maltreatment. Three research questions were examined: 1.What are the attitudes, behaviors and contexts of fathers who have abused or neglected a child that relate to maltreatment? 2. What are the resources and capacities of these fathers which could be capitalized on? 3. How does goodness-of-fit or a poor fit between the father and child impact the parenting relationships of these fathers? Fifteen fathers …

Present With An Uncertain Future: Dispositional Mindfulness, Covariation Bias, And Event-Related Potential Responses To Emotional Stimuli In Uncertain Contexts, Robert J. Goodman

Theses and Dissertations

Uncertainty represents a robust threat that can amplify aversive experiences and exaggerate negative expectations about uncertain future outcomes. Mindfulness – an open and receptive attention to present moment experiences -- has been shown to facilitate adaptive regulation when faced with a variety of distinct emotional threats. Reduced experiential avoidance and equanimity in the face of unpleasant emotional experiences have been theorized as central to these emotional regulatory benefits. The present study explored whether dispositional mindfulness would promote adaptive responses to uncertainty during the anticipation of, and after exposure to emotional stimuli, as indicated by self-reports and neural (event-related potential) markers …

Epigenetic Alterations Of Toll-Like Receptors By Tet2 In Spontaneous Preterm Labor, Anuja Chumble

Theses and Dissertations

Increasing evidence implicates the presence of bacteria in intrauterine tissues as an important risk factor for spontaneous preterm labor. Epigenetic alterations of innate immunity genes may increase the mother’s sensitivity to subclinical levels of bacteria. This study examined the presence of TET2, TLR-2, and TLR-9 in intrauterine tissue, and evaluated whether epigenetic alterations of these genes, as well as IL-8, changed their expression in human decidual tissue and a macrophage cell culture. Immunohistochemicalstaining was used to detect the presence of these proteins in intrauterine tissue. Gene expression changes were evaluated in stimulated monocytes and macrophages. Fluorescence immunohistochemistry was used to …