433 research outputs found

    The Locus Ceruleus in PTSD

    Get PDF
    NO ABSTRACT: This is 750 word encyclopedia entr

    Sea urchin populations in the Salish Sea: recent findings regarding invertebrates that support a prized fishery and play an important role in nearshore ecosystems.

    Get PDF
    Major changes in urchin populations have been reported in recent years around the world, coupled with profound cascading effects on nearshore ecosystems. Extreme climatic events are postulated to be a common driver, along with changes in populations of predators such as sea otters and sea stars. This panel brings together ecologists from British Columbia and Washington to highlight recent results on spatial patterns and temporal trends in sea urchin populations in the Salish Sea and the exposed coast. Findings suggest differences among locations in both species abundances and ecological interactions. Topics include: abundances of individual species, locations with large aggregations, trophic interactions, potential ecosystem effects, hypothesized drivers of observed change, and effects of climate change on these dynamics. These findings touch upon two topics of key interest to communities and resource managers: sea urchin fisheries and ecosystem impacts related to over-grazing

    The chaperone protein clusterin may serve as a cerebrospinal fluid biomarker for chronic spinal cord disorders in the dog

    Get PDF
    Chronic spinal cord dysfunction occurs in dogs as a consequence of diverse aetiologies, including long-standing spinal cord compression and insidious neurodegenerative conditions. One such neurodegenerative condition is canine degenerative myelopathy (DM), which clinically is a challenge to differentiate from other chronic spinal cord conditions. Although the clinical diagnosis of DM can be strengthened by the identification of the Sod1 mutations that are observed in affected dogs, genetic analysis alone is insufficient to provide a definitive diagnosis. There is a requirement to identify biomarkers that can differentiate conditions with a similar clinical presentation, thus facilitating patient diagnostic and management strategies. A comparison of the cerebrospinal fluid (CSF) protein gel electrophoresis profile between idiopathic epilepsy (IE) and DM identified a protein band that was more prominent in DM. This band was subsequently found to contain a multifunctional protein clusterin (apolipoprotein J) that is protective against endoplasmic reticulum (ER) stress-mediated apoptosis, oxidative stress, and also serves as an extracellular chaperone influencing protein aggregation. Western blot analysis of CSF clusterin confirmed elevated levels in DM compared to IE (p < 0.05). Analysis of spinal cord tissue from DM and control material found that clusterin expression was evident in neurons and that the clusterin mRNA levels from tissue extracts were elevated in DM compared to the control. The plasma clusterin levels was comparable between these groups. However, a comparison of clusterin CSF levels in a number of neurological conditions found that clusterin was elevated in both DM and chronic intervertebral disc disease (cIVDD) but not in meningoencephalitis and IE. These findings indicate that clusterin may potentially serve as a marker for chronic spinal cord disease in the dog; however, additional markers are required to differentiate DM from a concurrent condition such as cIVDD

    D-brane Charges in Gravitational Duals of 2+1 Dimensional Gauge Theories and Duality Cascades

    Full text link
    We perform a systematic analysis of the D-brane charges associated with string theory realizations of d=3 gauge theories, focusing on the examples of the N=4 supersymmetric U(N)xU(N+M) Yang-Mills theory and the N=3 supersymmetric U(N)xU(N+M) Yang-Mills-Chern-Simons theory. We use both the brane construction of these theories and their dual string theory backgrounds in the supergravity approximation. In the N=4 case we generalize the previously known gravitational duals to arbitrary values of the gauge couplings, and present a precise mapping between the gravity and field theory parameters. In the N=3 case, which (for some values of N and M) flows to an N=6 supersymmetric Chern-Simons-matter theory in the IR, we argue that the careful analysis of the charges leads to a shift in the value of the B-field in the IR solution by 1/2, in units where its periodicity is one, compared to previous claims. We also suggest that the N=3 theories may exhibit, for some values of N and M, duality cascades similar to those of the Klebanov-Strassler theory.Comment: 47 pages, 9 figures; minor changes, references adde

    Structure in 6D and 4D N=1 supergravity theories from F-theory

    Get PDF
    We explore some aspects of 4D supergravity theories and F-theory vacua that are parallel to structures in the space of 6D theories. The spectrum and topological terms in 4D supergravity theories correspond to topological data of F-theory geometry, just as in six dimensions. In particular, topological axion-curvature squared couplings appear in 4D theories; these couplings are characterized by vectors in the dual to the lattice of axion shift symmetries associated with string charges. These terms are analogous to the Green-Schwarz terms of 6D supergravity theories, though in 4D the terms are not generally linked with anomalies. We outline the correspondence between F-theory topology and data of the corresponding 4D supergravity theories. The correspondence of geometry with structure in the low-energy action illuminates topological aspects of heterotic-F-theory duality in 4D as well as in 6D. The existence of an F-theory realization also places geometrical constraints on the 4D supergravity theory in the large-volume limit.Comment: 63 page

    Sociological and Communication-Theoretical Perspectives on the Commercialization of the Sciences

    Get PDF
    Both self-organization and organization are important for the further development of the sciences: the two dynamics condition and enable each other. Commercial and public considerations can interact and "interpenetrate" in historical organization; different codes of communication are then "recombined." However, self-organization in the symbolically generalized codes of communication can be expected to operate at the global level. The Triple Helix model allows for both a neo-institutional appreciation in terms of historical networks of university-industry-government relations and a neo-evolutionary interpretation in terms of three functions: (i) novelty production, (i) wealth generation, and (iii) political control. Using this model, one can appreciate both subdynamics. The mutual information in three dimensions enables us to measure the trade-off between organization and self-organization as a possible synergy. The question of optimization between commercial and public interests in the different sciences can thus be made empirical.Comment: Science & Education (forthcoming

    Provider imposed restrictions to clients’ access to family planning in urban Uttar Pradesh, India: a mixed methods study

    Get PDF
    BACKGROUND: Medical barriers refer to unnecessary policies or procedures imposed by health care providers that are not necessarily medically advised; these restrictions impede clients’ access to family planning (FP). This mixed methods study investigates provider imposed barriers to provision of FP using recent quantitative and qualitative data from urban Uttar Pradesh, India. METHODS: Baseline quantitative data were collected in six cities in Uttar Pradesh, India from service delivery points (SDP), using facility audits, exit interviews, and provider surveys; for this study, the focus is on the provider surveys. More than 250 providers were surveyed in each city. Providers were asked about the FP methods they provide, and if they restrict clients’ access to each method based on age, parity, partner consent, or marital status. For the qualitative research, we conducted one-on-one interviews with 21 service providers in four of the six cities in Uttar Pradesh. Each interview lasted approximately 45 minutes. RESULTS: The quantitative findings show that providers restrict clients’ access to spacing and long-acting and permanent methods of FP based on age, parity, partner consent and marital status. Qualitative findings reinforce that providers, at times, make judgments about their clients’ education, FP needs and ability to understand FP options thereby imposing unnecessary barriers to FP methods. CONCLUSIONS: Provider restrictions on FP methods are common in these urban Uttar Pradesh sites. This means that women who are young, unmarried, have few or no children, do not have the support of their partner, or are less educated may not be able to access or use FP or their preferred method. These findings highlight the need for in-service training for staff, with a focus on reviewing current guidelines and eligibility criteria for provision of methods

    No advantage for remembering horizontal over vertical spatial locations learned from a single viewpoint

    Get PDF
    Previous behavioral and neurophysiological research has shown better memory for horizontal than for vertical locations. In these studies, participants navigated toward these locations. In the present study we investigated whether the orientation of the spatial plane per se was responsible for this difference. We thus had participants learn locations visually from a single perspective and retrieve them from multiple viewpoints. In three experiments, participants studied colored tags on a horizontally or vertically oriented board within a virtual room and recalled these locations with different layout orientations (Exp. 1) or from different room-based perspectives (Exps. 2 and 3). All experiments revealed evidence for equal recall performance in horizontal and vertical memory. In addition, the patterns for recall from different test orientations were rather similar. Consequently, our results suggest that memory is qualitatively similar for both vertical and horizontal two-dimensional locations, given that these locations are learned from a single viewpoint. Thus, prior differences in spatial memory may have originated from the structure of the space or the fact that participants navigated through it. Additionally, the strong performance advantages for perspective shifts (Exps. 2 and 3) relative to layout rotations (Exp. 1) suggest that configurational judgments are not only based on memory of the relations between target objects, but also encompass the relations between target objects and the surrounding room—for example, in the form of a memorized view

    Overexpression of miR-128 specifically inhibits the truncated isoform of NTRK3 and upregulates BCL2 in SH-SY5Y neuroblastoma cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Neurotrophins and their receptors are key molecules in the regulation of neuronal differentiation and survival. They mediate the survival of neurons during development and adulthood and are implicated in synaptic plasticity. The human neurotrophin-3 receptor gene <it>NTRK3 </it>yields two major isoforms, a full-length kinase-active form and a truncated non-catalytic form, which activates a specific pathway affecting membrane remodeling and cytoskeletal reorganization. The two variants present non-overlapping 3'UTRs, indicating that they might be differentially regulated at the post-transcriptional level. Here, we provide evidence that the two isoforms of <it>NTRK3 </it>are targeted by different sets of microRNAs, small non-coding RNAs that play an important regulatory role in the nervous system.</p> <p>Results</p> <p>We identify one microRNA (miR-151-3p) that represses the full-length isoform of <it>NTRK3 </it>and four microRNAs (miR-128, miR-485-3p, miR-765 and miR-768-5p) that repress the truncated isoform. In particular, we show that the overexpression of miR-128 - a brain enriched miRNA - causes morphological changes in SH-SY5Y neuroblastoma cells similar to those observed using an siRNA specifically directed against truncated <it>NTRK3</it>, as well as a significant increase in cell number. Accordingly, transcriptome analysis of cells transfected with miR-128 revealed an alteration of the expression of genes implicated in cytoskeletal organization as well as genes involved in apoptosis, cell survival and proliferation, including the anti-apoptotic factor <it>BCL2</it>.</p> <p>Conclusions</p> <p>Our results show that the regulation of <it>NTRK3 </it>by microRNAs is isoform-specific and suggest that neurotrophin-mediated processes are strongly linked to microRNA-dependent mechanisms. In addition, these findings open new perspectives for the study of the physiological role of miR-128 and its possible involvement in cell death/survival processes.</p
    corecore