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Species Shout-Outs From Abdul To Zebra: Encouraging Nonmajors To Communicate In The Biology Classroom, Christina P. Colon

Publications and Research

No abstract provided.

On The Social Construction Of Hellenism Cold War Narratives Of Modernity, Development And Democracy For Greece, Despina Lalaki

Publications and Research

Hellenism is one of those overarching, ever-changing narratives always subject to historical circumstances, intellectual fashions and political needs. Conversely, it is fraught with meaning and conditioning powers, enabling and constraining imagination and practical life. In this essay I tease out the hold that the idea of Hellas has had on post-war Greece and I explore the ways in which the American anti-communist rhetoric and discussions about political and economic stabilization appropriated and rearticulated Hellenism. Central to this history of transformations are the archaeologists; the archaeologists as intellectuals, as producers of culture who, while stepping in and out of their disciplinary …

Attack Rates Assessment Of The 2009 Pandemic H1n1 Influenza A In Children And Their Contacts: A Systematic Review And Meta-Analysis, Aharona Glatman-Freedman, Ian Portelli, Susan K. Jacobs, Justin I. Mathew, Jonathan E. Slutzman, Lewis R. Goldfrank, Silas W. Smith

Publications and Research

Background The recent H1N1 influenza A pandemic was marked by multiple reports of illness and hospitalization in children, suggesting that children may have played a major role in the propagation of the virus. A comprehensive detailed analysis of the attack rates among children as compared with their contacts in various settings is of great importance for understanding their unique role in influenza pandemics. Methodology/Principal Findings We searched MEDLINE (PubMed) and Embase for published studies reporting outbreak investigations with direct measurements of attack rates of the 2009 pandemic H1N1 influenza A among children, and quantified how these compare with those of …

Effects Of Motivation On Reward And Attentional Networks: An Fmri Study, Iliyan Ivanov, Xun Liu, Suzanne Clerkin, Kurt Schulz, Karl Friston, Jeffrey H. Newcorn, Jin Fan

Publications and Research

Existing evidence suggests that reward and attentional networks function in concert and that activation in one system influences the other in a reciprocal fashion; however, the nature of these influences remains poorly understood. We therefore developed a three-component task to assess the interaction effects of reward anticipation and conflict resolution on the behavioral performance and the activation of brain reward and attentional systems. Sixteen healthy adult volunteers aged 21–45 years were scanned with functional magnetic resonance imaging (fMRI) while performing the task. A two-way repeated measures analysis of variance (ANOVA) with cue (reward vs. non-reward) and target (congruent vs. incongruent) …

Effects Of Carpal Tunnel Syndrome On Adaptation Of Multi-Digit Forces To Object Mass Distribution For Whole-Hand Manipulation, Wei Zhang, Jamie A. Johnston, Mark A. Ross, Brandon J. Coakley, Elizabeth A. Gleason, Amylou C. Dueck, Marco Santello

Publications and Research

Background Carpal tunnel syndrome (CTS) is a compression neuropathy of the median nerve that results in sensorimotor deficits in the hand. Until recently, the effects of CTS on hand function have been studied using mostly two-digit grip tasks. The purpose of this study was to investigate the coordination of multi-digit forces as a function of object center of mass (CM) during whole-hand grasping. Methods Fourteen CTS patients and age- and gender-matched controls were instructed to grasp, lift, hold, and release a grip device with five digits for seven consecutive lifts while maintaining its vertical orientation. The object CM was changed …

Gene Flow On Ice: The Role Of Sea Ice And Whaling In Shaping Holarctic Genetic Diversity And Population Differentiation In Bowhead Whales (Balaena Mysticetus), S Elizabeth Alter, Howard C. Rosenbaum, Lianne D. Postma, Peter Whitridge, Cork Gaines, Diana Weber, Mary G. Egan, Melissa Lindsay, George Amato, Larry Dueck, Robert L. Brownell, Mads-Peter Heide-Jørgensen, Kristin L. Laidre, Gisella Caccone, Brittany L. Hancock

Publications and Research

Sea ice is believed to be a major factor shaping gene flow for polar marine organisms, but it remains unclear to what extent it represents a true barrier to dispersal for arctic cetaceans. Bowhead whales are highly adapted to polar sea ice and were targeted by commercial whalers throughout Arctic and subarctic seas for at least four centuries, resulting in severe reductions in most areas. Both changing ice conditions and reductions due to whaling may have affected geographic distribution and genetic diversity throughout their range, but little is known about range-wide genetic structure or whether it differed in the past. …

What Can Phages Tell Us About Host-Pathogen Coevolution?, John J. Dennehy

Publications and Research

The outcomes of host-parasite interactions depend on the coevolutionary forces acting upon them, but because every host-parasite relation is enmeshed in a web of biotic and abiotic interactions across a heterogeneous landscape, host-parasite coevolution has proven difficult to study. Simple laboratory phage-bacteria microcosms can ameliorate this difficulty by allowing controlled, well-replicated experiments with a limited number of interactors. Genetic, population, and life history data obtained from these studies permit a closer examination of the fundamental correlates of host-parasite coevolution. In this paper, I describe the results of phage-bacteria coevolutionary studies and their implications for the study of host-parasite coevolution. Recent …

Medication Deserts: Survey Of Neighborhood Disparities In Availability Of Prescription Medications, Philippe Amstislavski, Ariel Matthews, Sarah Sheffield, Andrew R. Maroko, Jeremy Weedon

Publications and Research

Background Only a small amount of research has focused on the relationship between socio-economic status (SES) and geographic access to prescription medications at community pharmacies in North America and Europe. To examine the relationship between a community’s socio-economic context and its residents’ geographic access to common medications in pharmacies, we hypothesized that differences are present in access to pharmacies across communities with different socio-economic environments, and in availability of commonly prescribed medications within pharmacies located in communities with different socio-economic status. Methods We visited 408 pharmacies located in 168 socio-economically diverse communities to assess the availability of commonly prescribed medications. …

The Use Of Indicators For Unobservable Product Qualities: Inferences Based On Consumer Sorting, Matthew G. Nagler, Fredi Kronenberg, Edward J. Kennelly, Bei Jiang, Chunhui Ma

Publications and Research

We propose a method for measuring the conjectural errors that inexpert consumers make relative to experts in using observable product characteristics as surrogate indicators of a valued unobservable characteristic. Observations on the unobservable characteristic, available to the researcher but not consumers, are used to divide the data into high- and low-quality subsamples. Separate hedonic estimation on the subsamples enables measurement of the relative valuations and conjectures of experts and non-experts with respect to indicators under the assumption that consumers sort across quality grades based on their appraisal expertise. The method is demonstrated using a small sample of SKU-level data on …

Orca Is Regulated By Ubiquitin-Mediated Degradation To Control Orc2 Function, Amy E. Ikui

Publications and Research

No abstract provided.

Effect Of Axonal Micro-Tubules On The Morphology Of Retinal Nerve Fibers Studied By Second-Harmonic Generation, Hyungsik Lim, John Danias

Publications and Research

Abstract. Many studies suggest that the degradation of microtubules in the retinal ganglion cells may be an early event in the progression of glaucoma. Because reflectance and birefringence of the retinal nerve fibers arise primarily from microtubules, the optical properties have been intensively studied for early detection of the disease. We previously reported a novel nonlinear optical signal from axonal microtubules for visualizing the retinal nerve fibers, namely second-harmonic generation (SHG). We demonstrate the use of axonal SHG to investigate the effect of microtubules on the morphology of the retinal nerve fiber bundles. Time-lapse SHG imaging of ex vivo rat …

Two-Photon Time-Lapse Microscopy Of Bodipy-Cholesterol Reveals Anomalous Sterol Diffusion In Chinese Hamster Ovary Cells, Frederik W. Lund, Michael A. Lomholt, Lukasz M. Solanko, Robert Bittman, Daniel Wüstner

Publications and Research

Background Cholesterol is an important membrane component, but our knowledge about its transport in cells is sparse. Previous imaging studies using dehydroergosterol (DHE), an intrinsically fluorescent sterol from yeast, have established that vesicular and non-vesicular transport modes contribute to sterol trafficking from the plasma membrane. Significant photobleaching, however, limits the possibilities for in-depth analysis of sterol dynamics using DHE. Co-trafficking studies with DHE and the recently introduced fluorescent cholesterol analog BODIPY-cholesterol (BChol) suggested that the latter probe has utility for prolonged live-cell imaging of sterol transport. Results We found that BChol is very photostable under two-photon (2P)-excitation allowing the acquisition …

Protein P7 Of The Cystovirus Φ6 Is Located At The Three-Fold Axis Of The Unexpanded Procapsid, Garrett Katz, Hui Wei, Alexandra Alimova, Al Katz, David Gene Morgan, Paul Gottlieb

Publications and Research

The objective of this study was to determine the location of protein P7, the RNA packaging factor, in the procapsid of the φ6 cystovirus. A comparison of cryo-electron microscopy high-resolution single particle reconstructions of the φ6 complete unexpanded procapsid, the protein P2-minus procapsid (P2 is the RNA directed RNA-polymerase), and the P7-minus procapsid, show that prior to RNA packaging the P7 protein is located near the three-fold axis of symmetry. Difference maps highlight the precise position of P7 and demonstrate that in P7-minus particles the P2 proteins are less localized with reduced densities at the three-fold axes. We propose that …

New Autonomous Motors Of Metal-Organic Framework (Mof) Powered By Reorganization Of Self-Assembled Peptides At Interfaces, Yasuhiro Ikezoe, Gosuke Washino, Takashi Uemura, Susumu Kitagawa, Hiroshi Matsui

Publications and Research

There have developed a variety of microsystems that harness energy and convert it to mechanical motion. Here we developed new autonomous biochemical motors by integrating metal-organic framework (MOF) and self-assembling peptides. MOF is applied as an energy-storing cell that assembles peptides inside nanoscale pores of the coordination framework. The robust assembling nature of peptides enables reconfiguring their assemblies at the water-MOF interface, which is converted to fuel energy. Re-organization of hydrophobic peptides could create the large surface tension gradient around the MOF and it efficiently powers the translation motion of MOF. As a comparison, the velocity of normalized by volume …

The Role Of The Caudal Superior Parietal Lobule In Updating Hand Location In Peripheral Vision: Further Evidence From Optic Ataxia, Joshua A. Granek, Laure Pisella, Annabelle Blangero, Yves Rossetti, Lauren E. Sergio

Publications and Research

Patients with optic ataxia (OA), who are missing the caudal portion of their superior parietal lobule (SPL), have difficulty performing visually-guided reaches towards extra-foveal targets. Such gaze and hand decoupling also occurs in commonly performed non-standard visuomotor transformations such as the use of a computer mouse. In this study, we test two unilateral OA patients in conditions of 1) a change in the physical location of the visual stimulus relative to the plane of the limb movement, 2) a cue that signals a required limb movement 180° opposite to the cued visual target location, or 3) both of these situations …

The Role Of Dental Hygienists In Conducting Rapid Hiv Testing, Anthony J. Santella, Susan H. Davide, Marilyn Cortell, Winnie Furnari, Janet Tuthill

Publications and Research

Expanding rapid HIV testing in the dental setting may increase the number of individuals who are aware of their HIV status and can begin medical care and social support services if seropositive and appropriate.

Competition Between Conjugation And M13 Phage Infection In Escherichia Coli In The Absence Of Selection Pressure: A Kinetic Study, Zhenmao Wan, Noel L. Goddard

Publications and Research

Inter- and intraspecies horizontal gene transfer enabled by bacterial secretion systems is a powerful mechanism for bacterial genome plasticity. The type IV secretion system of Escherichia coli, encoded by the F plasmid, enables cell-to-cell contact and subsequent DNA transfer known as conjugation. Conjugation is compromised by phage infection that specifically targets the secretion machinery. Hence, the use of phages to regulate the spread of genes, such as acquired antibiotic resistance or as general biosanitation agents, has gained interest. To predict the potential efficacy, the competition kinetics must first be understood. Using quantitative PCR to enumerate genomic loci in a resource-limited …

The Determinants Of Helminth Infection In Baboons, Rita Monfort

Publications and Research

THE DETERMINANTS OF HELMINTH INFECTION IN BABOONS

Summary Paragraph:

Intestinal parasitic helminths are common in wild primate populations [1, 2] and can impose a significant burden on their host’s fitness. Numerous factors can affect the prevalence and diversity of intestinal parasites in natural populations including environmental factors [3, 4], the host’s behavior and genetics [5, 6]. How these different factors interact in natural populations remains unclear. This is in all probability due to the fact that previous studies have seldom looked at the prevalence and diversity of parasitic helminths in the same species but in different habitats over periods longer …

What Is The Predictive Power Of The Colobine Protein-To-Fiber Model And Its Conservation Value?, Jan F. Gogarten, Melissa Guzman, Colin A. Chapman, Aerin L. Jacob, Patrick A. Omeja, Jessica Rothman

Publications and Research

Predicting variation in animal abundance across time and space has proven very difficult; however, a model exists to predict the biomass of small folivorous primates that has considerable correlative support. This model suggests that the protein-to-fiber ratio of leaves in a habitat can predict folivore biomass. Here we present an experimental test of this protein-to-fiber model to assess if the number of infant monkeys per female and group size can be predicted based on the leaf chemistry of a habitat. We expected regenerating forest in Kibale National Park, Uganda to have leaves with higher concentrations of crude protein and lower …

Lesula: A New Species Of Cercopithecus Monkey Endemic To The Democratic Republic Of Congo And Implications For Conservation Of Congo’S Central Basin, John A. Hart, Kate M. Detwiler, Christopher C. Gilbert, Andrew S. Burrell, James L. Fuller, Maurice Emetshu, Terese B. Hart, Ashley Vosper, Eric J. Sargis, Anthony J. Tosi

Publications and Research

In June 2007, a previously undescribed monkey known locally as “lesula” was found in the forests of the middle Lomami Basin in central Democratic Republic of Congo (DRC). We describe this new species as Cercopithecus lomamiensis sp. nov., and provide data on its distribution, morphology, genetics, ecology and behavior. C. lomamiensis is restricted to the lowland rain forests of central DRC between the middle Lomami and the upper Tshuapa Rivers. Morphological and molecular data confirm that C. lomamiensis is distinct from its nearest congener, C. hamlyni, from which it is separated geographically by both the Congo (Lualaba) and the Lomami …

Empirical Evaluation Of Scoring Functions For Bayesian Network Model Selection, Zhifa Liu, Brandon Malone, Changhe Yuan

Publications and Research

In this work, we empirically evaluate the capability of various scoring functions of Bayesian networks for recovering true underlying structures. Similar investigations have been carried out before, but they typically relied on approximate learning algorithms to learn the network structures. The suboptimal structures found by the approximation methods have unknown quality and may affect the reliability of their conclusions. Our study uses an optimal algorithm to learn Bayesian network structures from datasets generated from a set of gold standard Bayesian networks. Because all optimal algorithms always learn equivalent networks, this ensures that only the choice of scoring function affects the …

Risk Factor Detection As A Metric Of Starhs Performance For Hiv Incidence Surveillance Among Female Sex Workers In Kigali, Rwanda, Sarah L. Braunstein, Janneke H. Van De Wijgert, Joseph Vyankandondera, Evelyn Kestelyn, Justin Ntirushwa, Denis Nash

Publications and Research

Background:
The epidemiologic utility of STARHS hinges not only on producing accurate estimates of HIV incidence, but also on identifying risk factors for recent HIV infection.

Methods:
As part of an HIV seroincidence study, 800 Rwandan female sex workers (FSW) were HIV tested, with those testing positive further tested by BED-CEIA (BED) and AxSYM Avidity Index (Ax-AI) assays. A sample of HIV-negative (N=397) FSW were followed prospectively for HIV seroconversion. We compared estimates of risk factors for: 1) prevalent HIV infection; 2) recently acquired HIV infection (RI) based on three different STARHS classifications (BED alone, Ax-AI alone, BED/Ax-AI combined); and …

Sex & Vision I: Spatio-Temporal Resolution, Israel Abramov, James Gordon, Olga Feldman, Alla Chavarga

Publications and Research

Background Cerebral cortex has a very large number of testosterone receptors, which could be a basis for sex differences in sensory functions. For example, audition has clear sex differences, which are related to serum testosterone levels. Of all major sensory systems only vision has not been examined for sex differences, which is surprising because occipital lobe (primary visual projection area) may have the highest density of testosterone receptors in the cortex. We have examined a basic visual function: spatial and temporal pattern resolution and acuity. Methods We tested large groups of young adults with normal vision. They were screened with …

Sex And Vision Ii: Color Appearance Of Monochromatic Lights, Israel Abramov, James Gordon, Olga Feldman, Alla Chavarga

Publications and Research

Background Because cerebral cortex has a very large number of testosterone receptors, we examined the possible sex differences in color appearance of monochromatic lights across the visible spectrum. There is a history of men and women perceiving color differently. However, all of these studies deal with higher cognitive functions which may be culture-biased. We study basic visual functions, such as color appearance, without reference to any objects. We present here a detailed analysis of sex differences in primary chromatic sensations. Methods We tested large groups of young adults with normal vision, including spatial and temporal resolution, and stereopsis. Based on …

Early Invasion Of Brain Parenchyma By African Trypanosomes, Ute Frevert, Alexandru Movila, Olga V. Nikolskaia, Jayne Raper, Zachary B. Mackey, Maha Abdulla, James Mckerrow, Dennis J. Grab

Publications and Research

Human African trypanosomiasis or sleeping sickness is a vector-borne parasitic disease that has a major impact on human health and welfare in sub-Saharan countries. Based mostly on data from animal models, it is currently thought that trypanosome entry into the brain occurs by initial infection of the choroid plexus and the circumventricular organs followed days to weeks later by entry into the brain parenchyma. However, Trypanosoma brucei bloodstream forms rapidly cross human brain microvascular endothelial cells in vitro and appear to be able to enter the murine brain without inflicting cerebral injury. Using a murine model and intravital brain imaging, …

Chronic Ketamine Administration Modulates Midbrain Dopamine System In Mice, Sijie Tan, Wai Ping Lam, Maria S. M. Wai, Wan-Hua Amy Yu, David T. Yew

Publications and Research

Ketamine is an anesthetic and a popular abusive drug. As an anesthetic, effects of ketamine on glutamate and GABA transmission have been well documented but little is known about its long-term effects on the dopamine system. In the present study, the effects of ketamine on dopamine were studied in vitro and in vivo. In pheochromocytoma (PC 12) cells and NGF differentiated-PC 12 cells, ketamine decreased the cell viability while increasing dopamine (DA) concentrations in a dose-related manner. However, ketamine did not affect the expression of genes involved in DA synthesis. In the long-term (3 months) ketamine treated mice, significant increases …

The Structural Stability Of The Endothelial Glycocalyx After Enzymatic Removal Of Glycosaminoglycans, Ye Zeng, Eno E. Ebong, Bingmei M. Fu, John M. Tarbell

Publications and Research

Rationale It is widely believed that glycosaminoglycans (GAGs) and bound plasma proteins form an interconnected gel-like structure on the surface of endothelial cells (the endothelial glycocalyx layer–EGL) that is stabilized by the interaction of its components. However, the structural organization of GAGs and proteins and the contribution of individual components to the stability of the EGL are largely unknown. Objective To evaluate the hypothesis that the interconnected gel-like glycocalyx would collapse when individual GAG components were almost completely removed by a specific enzyme. Methods and Results Using confocal microscopy, we observed that the coverage and thickness of heparan sulfate (HS), …

Γ-Synuclein Interacts With Phospholipase Cβ2 To Modulate G Protein Activation, Urszula Golebiewska, Yuanjian Guo, Narindra Khalikaprasad, Cassandra Zurawsky, V. Siddhartha Yerramilli, Suzanne Scarlata

Publications and Research

Phospholipase Cβ2 (PLC β2) is activated by G proteins and generates calcium signals in cells. PLCβ2 is absent in normal breast tissue, but is highly expressed in breast tumors where its expression is correlated with the progression and migration of the tumor. This pattern of expression parallels the expression of the breast cancer specific gene protein 1 which is also known as γ-synuclein. The cellular function of γ-synuclein and the role it plays in proliferation are unknown. Here, we determined whether γ-synuclein can interact with PLCβ2 and affect its activity. Using co-immunprecitation and co-immunofluorescence, we find that in both benign …

Communication Activity In A Social Network: Relation Between Long-Term Correlations And Inter-Event Clustering, Diego Rybski, Sergey V. Buldyrev, Shlomo Havlin, Fredrik Liljeros, Hernán A. Makse

Publications and Research

Human communication in social networks is dominated by emergent statistical laws such as non-trivial correlations and temporal clustering. Recently, we found long-term correlations in the user's activity in social communities. Here, we extend this work to study the collective behavior of the whole community with the goal of understanding the origin of clustering and long-term persistence. At the individual level, we find that the correlations in activity are a byproduct of the clustering expressed in the power-law distribution of inter-event times of single users, i.e. short periods of many events are separated by long periods of no events. On the …

Weaponizing Tear Gas: Bahrain’S Unprecedented Use Of Toxic Chemical Agents Against Civilians., Richard Sollom, Holly G. Atkinson

Publications and Research

The Bahraini government’s response to the early 2011 pro-democracy protests was brutal, systematic, and violent. In addition to birdshot and rubber bullets, government law enforcement attacked unarmed protestors with toxic chemical agents including tear gas. The government’s crackdown on the medical profession was especially harmful, as security forces arrested and detained doctors, raided health facilities, and obstructed patients from receiving necessary care. This report’s findings are based on field research that the authors conducted in Bahrain (April 2012) to investigate excessive use of force by law enforcement officials since June 2011—the end of Bahrain’s state of emergency. The medico-legal team …