3,201 research outputs found

    Stem cells and the origin of gliomas: A historical reappraisal with molecular advancements.

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    The biology of both normal and tumor development clearly possesses overlapping and parallel features. Oncogenes and tumor suppressors are relevant not only in tumor biology, but also in physiological developmental regulators of growth and differentiation. Conversely, genes identified as regulators of developmental biology are relevant to tumor biology. This is particularly relevant in the context of brain tumors, where recent evidence is mounting that the origin of brain tumors, specifically gliomas, may represent dysfunctional developmental neurobiology. Neural stem cells are increasingly being investigated as the cell type that originally undergoes malignant transformation - the cell of origin - and the evidence for this is discussed

    Absorbtion Kinetics of Some Purines, Pyrimidines, and Nucleosides in Taenia Crassiceps Larvae

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    Paper by Gary L. Uglem and Michael G. Lev

    Penetrating craniocerebral injury resultant from gunshot wounds: gang-related injury in children and adolescents

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    Journal ArticleWE PROSPECTIVELY AND retrospectively reviewed a series of 780 patients who presented to the University of Southern California/Los Angeles County Medical Center with a diagnosis of gunshot wound to the brain during an 8-year period. Of these, 105 were children ranging in age from 6 months to 17 years. Injuries were gang related in 76 (72%) children and adolescents. Stepwise linear regression analysis was used to formulate a predictive model of outcome in this population. Patient age (F = 10.92), sex (F = 9.32), occipital entry site (F= 8,17), bihemispheric injury (F= 8,50), and admission Glasgow Coma Scale (F= 69.91) were all found to correlate with outcome (P < 0.05). Significant differences between pediatric and adult populations were noted in transit time, entrance site, and age-related outcome. Occipital or assassination-type wounds were most common in children. In addition, a younger age was associated with poor outcome (P < 0,0001), We describe both the economic and racial trends in our population of patients in addition to weapon type and lexicological evaluation. The Department of Neurological Surgery is becoming directly involved in providing information to children at the junior high school level regarding gang activity and brain and spinal cord injury. In conjunction with the Community Youth Gang Services Organization and Think First Organization, we are attempting to integrate prevention through education and community mobilization. This is a plan aimed at informing and recovering the youth affected by gangs

    Application of the United States Soybean Export Council program's soy-optimized floating feeds and low volume, high density cage aquaculture technologies

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    The United States Soybean Export Council s (USSEC) Soy-In-Aquaculture (SIA) project in the Philippines introduced the Low Volume High Density (LVHD) cage culture production methodology in 2003. The aim of this technology is to maximize farmers profit, improve productivity, reduce feed conversion ratios (FCR) and limit environmental degradation. The Philippine fish farmers were very conservative and hesitant about adopting the USSEC SIA Low Volume High Density (LVHD) cage culture technology, particularly the new feeding techniques using extruded floating feeds. This conservative attitude was highlighted with different projects using Nile tilapia (Oreochromis niloticus), milkfish (Chanos chanos) and snubnose pompano (Trachinotus blochii) in USSEC SIA LVHD cage feeding demonstrations conducted in different commercial farms in the Philippines

    Conservation status of the Georgia Blind Salamander (Eurycea wallacei) from the Floridan Aquifer of Florida and Georgia

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    The Georgia Blind Salamander (Eurycea wallacei) is a poorly understood stygobitic plethodontid salamander found in the Floridan Aquifer of Florida and Georgia, USA. Its distribution is poorly delimited and little information is available on the ecology and life history of the species. We summarize existing information on the Georgia Blind Salamander and report new findings with regard to distribution, conservation status, and aspects of its ecology and life history from recent surveys in Florida and Georgia, including anecdotal observations made by local cave divers. We also&nbsp; present data on the prevalence of Batrachochytrium dendrobatidis and discuss potential measures and challenges involved in conservation. Georgia Blind Salamanders are known from at least 35 localities within five United States Geological Survey (USGS) HUC8 watersheds in Florida and Georgia, all within the groundwater of the Upper Floridan Aquifer. Some populations may be large, as cave divers have observed &gt;100 salamanders in a single dive at three localities and reported densities up to 10 salamanders per square meter. We confirm through direct observation that the Dougherty Plain Cave Crayfish (Cambarus cryptodytes) is a predator of E. wallacei. Although we found no evidence that any populations of the Georgia Blind Salamander have been infected by amphibian chytrid fungus, clear threats remain and include: (1) An “at risk” ranking by USGS of the Floridian Aquifer for contamination; (2) overharvesting of groundwater; (3) the presence of an emergent infectious amphibian disease in surface amphibians in the region (e.g., amphibian chytrid fun- gus); and (4) a lack of data on the basic biology and ecology of the species. We recommend the following conservation actions: (1) Better regulations and improved methods for retaining pesticide and fertilizer contaminants on the surface; (2) regulatory review of agricultural crops grown in the region and the establishment of systems and crops that do not require center pivot irrigation; (3) regular monitoring for disease across the range of the species; and (4) establishment of multiple assurance colonies such that captive specimens genetically represent at least half of the known populations

    Strong polarization mode coupling in microresonators

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    We observe strong modal coupling between the TE00 and TM00 modes in Si3N4 ring resonators revealed by avoided crossings of the corresponding resonances. Such couplings result in significant shifts of the resonance frequencies over a wide range around the crossing points. This leads to an effective dispersion that is one order of magnitude larger than the intrinsic dispersion and creates broad windows of anomalous dispersion. We also observe the changes to frequency comb spectra generated in Si3N4 microresonators due polarization mode and higher-order mode crossings and suggest approaches to avoid these effects. Alternatively, such polarization mode-crossings can be used as a novel tool for dispersion engineering in microresonators.Comment: Comments are very welcome (send to corresponding author

    Carbon Free Boston: Technical Summary

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    Part of a series of reports that includes: Carbon Free Boston: Summary Report; Carbon Free Boston: Social Equity Report; Carbon Free Boston: Buildings Technical Report; Carbon Free Boston: Transportation Technical Report; Carbon Free Boston: Waste Technical Report; Carbon Free Boston: Energy Technical Report; Carbon Free Boston: Offsets Technical Report; Available at http://sites.bu.edu/cfb/OVERVIEW: This technical summary is intended to argument the rest of the Carbon Free Boston technical reports that seek to achieve this goal of deep mitigation. This document provides below: a rationale for carbon neutrality, a high level description of Carbon Free Boston’s analytical approach; a summary of crosssector strategies; a high level analysis of air quality impacts; and, a brief analysis of off-road and street light emissions.Published versio
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