307 research outputs found
Intravenous chlorpromazine in the acute treatment of episodic tension-type headache: a randomized, placebo controlled, double-blind study
Observation of Coherent Elastic Neutrino-Nucleus Scattering
The coherent elastic scattering of neutrinos off nuclei has eluded detection
for four decades, even though its predicted cross-section is the largest by far
of all low-energy neutrino couplings. This mode of interaction provides new
opportunities to study neutrino properties, and leads to a miniaturization of
detector size, with potential technological applications. We observe this
process at a 6.7-sigma confidence level, using a low-background, 14.6-kg
CsI[Na] scintillator exposed to the neutrino emissions from the Spallation
Neutron Source (SNS) at Oak Ridge National Laboratory. Characteristic
signatures in energy and time, predicted by the Standard Model for this
process, are observed in high signal-to-background conditions. Improved
constraints on non-standard neutrino interactions with quarks are derived from
this initial dataset
High Levels of Sediment Contamination Have Little Influence on Estuarine Beach Fish Communities
While contaminants are predicted to have measurable impacts on fish assemblages, studies have rarely assessed this potential in the context of natural variability in physico-chemical conditions within and between estuaries. We investigated links between the distribution of sediment contamination (metals and PAHs), physico-chemical variables (pH, salinity, temperature, turbidity) and beach fish assemblages in estuarine environments. Fish communities were sampled using a beach seine within the inner and outer zones of six estuaries that were either heavily modified or relatively unmodified by urbanization and industrial activity. All sampling was replicated over two years with two periods sampled each year. Shannon diversity, biomass and abundance were all significantly higher in the inner zone of estuaries while fish were larger on average in the outer zone. Strong differences in community composition were also detected between the inner and outer zones. Few differences were detected between fish assemblages in heavily modified versus relatively unmodified estuaries despite high concentrations of sediment contaminants in the inner zones of modified estuaries that exceeded recognized sediment quality guidelines. Trends in species distributions, community composition, abundance, Shannon diversity, and average fish weight were strongly correlated to physico-chemical variables and showed a weaker relationship to sediment metal contamination. Sediment PAH concentrations were not significantly related to the fish assemblage. These findings suggest that variation in some physico-chemical factors (salinity, temperature, pH) or variables that co-vary with these factors (e.g., wave activity or grain size) have a much greater influence on this fish assemblage than anthropogenic stressors such as contamination
Mapping of the Disease Locus and Identification of ADAMTS10 As a Candidate Gene in a Canine Model of Primary Open Angle Glaucoma
Primary open angle glaucoma (POAG) is a leading cause of blindness worldwide, with elevated intraocular pressure as an important risk factor. Increased resistance to outflow of aqueous humor through the trabecular meshwork causes elevated intraocular pressure, but the specific mechanisms are unknown. In this study, we used genome-wide SNP arrays to map the disease gene in a colony of Beagle dogs with inherited POAG to within a single 4 Mb locus on canine chromosome 20. The Beagle POAG locus is syntenic to a previously mapped human quantitative trait locus for intraocular pressure on human chromosome 19. Sequence capture and next-generation sequencing of the entire canine POAG locus revealed a total of 2,692 SNPs segregating with disease. Of the disease-segregating SNPs, 54 were within exons, 8 of which result in amino acid substitutions. The strongest candidate variant causes a glycine to arginine substitution in a highly conserved region of the metalloproteinase ADAMTS10. Western blotting revealed ADAMTS10 protein is preferentially expressed in the trabecular meshwork, supporting an effect of the variant specific to aqueous humor outflow. The Gly661Arg variant in ADAMTS10 found in the POAG Beagles suggests that altered processing of extracellular matrix and/or defects in microfibril structure or function may be involved in raising intraocular pressure, offering specific biochemical targets for future research and treatment strategies
Structure and dendroecology of Thuja occidentalis in disjunct stands south of its contiguous range in the central Appalachian Mountains, USA
Pathways between Primary Production and Fisheries Yields of Large Marine Ecosystems
The shift in marine resource management from a compartmentalized approach of dealing with resources on a species basis to an approach based on management of spatially defined ecosystems requires an accurate accounting of energy flow. The flow of energy from primary production through the food web will ultimately limit upper trophic-level fishery yields. In this work, we examine the relationship between yield and several metrics including net primary production, chlorophyll concentration, particle-export ratio, and the ratio of secondary to primary production. We also evaluate the relationship between yield and two additional rate measures that describe the export of energy from the pelagic food web, particle export flux and mesozooplankton productivity. We found primary production is a poor predictor of global fishery yields for a sample of 52 large marine ecosystems. However, chlorophyll concentration, particle-export ratio, and the ratio of secondary to primary production were positively associated with yields. The latter two measures provide greater mechanistic insight into factors controlling fishery production than chlorophyll concentration alone. Particle export flux and mesozooplankton productivity were also significantly related to yield on a global basis. Collectively, our analyses suggest that factors related to the export of energy from pelagic food webs are critical to defining patterns of fishery yields. Such trophic patterns are associated with temperature and latitude and hence greater yields are associated with colder, high latitude ecosystems
Whole Genomes of Chandipura Virus Isolates and Comparative Analysis with Other Rhabdoviruses
The Chandipura virus (CHPV) belonging to the Vesiculovirus genus and Rhabdoviridae family, has recently been associated with a number of encephalitis epidemics, with high mortality in children, in different parts of India. No full length genome sequences of CHPV isolates were available in GenBank and little is known about the molecular markers for pathogenesis. In the present study, we provide the complete genomic sequences of four isolates from epidemics during 2003β2007. These sequences along with the deduced sequence of the prototype isolate of 1965 were analysed using phylogeny, motif search, homology modeling and epitope prediction methods. Comparison with other rhaboviruses was also done for functional extrapolations. All CHPV isolates clustered with the Isfahan virus and maintained several functional motifs of other rhabdoviruses. A notable difference with the prototype vesiculovirus, Vesicular Stomatitis Virus was in the L-domain flanking sequences of the M protein that are known to be crucial for interaction with host proteins. With respect to the prototype isolate, significant additional mutations were acquired in the 2003β2007 isolates. Several mutations in G mapped onto probable antigenic sites. A mutation in N mapped onto regions crucial for N-N interaction and a putative T-cell epitope. A mutation in the Casein kinase II phosphorylation site in P may attribute to increased rates of phosphorylation. Gene junction comparison revealed changes in the M-G junction of all the epidemic isolates that may have implications on read-through and gene transcription levels. The study can form the basis for further experimental verification and provide additional insights into the virulence determinants of the CHPV
Geographic range predicts photosynthetic and growth response to warming in co-occurring tree species
www.nature.comPopulations near the warm edge of species ranges may be particularly sensitive to climate change, but lack of empirical data on responses to warming represents a key gap in understanding future range dynamics. Herein we document the impacts of experimental warming on the performance of 11 boreal and temperate forest species that co-occur at the ecotone between these biomes in North America. We measured in situ net photosynthetic carbon gain and growth of >4,100 juvenile trees from local seed sources exposed to a chamberless warming experiment that used infrared heat lamps and soil heating cables to elevate temperatures by +3.4 Β°C above- and belowground for three growing seasons across 48 plots at two sites. In these ecologically realistic field settings, species growing nearest their warm range limit exhibited reductions in net photosynthesis and growth, whereas species near their cold range limit responded positively to warming. Differences among species in their three-year growth responses to warming parallel their photosynthetic responses to warming, suggesting that leaf-level responses may scale to whole-plant performance. These responses are consistent with the hypothesis, from observational data and models, that warming will reduce the competitive ability of currently dominant southern boreal species compared with locally rarer co-occurring species that dominate warmer neighbouring regions. Β© 2015 Macmillan Publishers Limited. All rights reserved
Effort-related functions of nucleus accumbens dopamine and associated forebrain circuits
Background
Over the last several years, it has become apparent that there are critical problems with the hypothesis that brain dopamine (DA) systems, particularly in the nucleus accumbens, directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food. Hypotheses related to DA function are undergoing a substantial restructuring, such that the classic emphasis on hedonia and primary reward is giving way to diverse lines of research that focus on aspects of instrumental learning, reward prediction, incentive motivation, and behavioral activation.
Objective
The present review discusses dopaminergic involvement in behavioral activation and, in particular, emphasizes the effort-related functions of nucleus accumbens DA and associated forebrain circuitry.
Results
The effects of accumbens DA depletions on food-seeking behavior are critically dependent upon the work requirements of the task. Lever pressing schedules that have minimal work requirements are largely unaffected by accumbens DA depletions, whereas reinforcement schedules that have high work (e.g., ratio) requirements are substantially impaired by accumbens DA depletions. Moreover, interference with accumbens DA transmission exerts a powerful influence over effort-related decision making. Rats with accumbens DA depletions reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and instead, these rats select a less-effortful type of food-seeking behavior.
Conclusions
Along with prefrontal cortex and the amygdala, nucleus accumbens is a component of the brain circuitry regulating effort-related functions. Studies of the brain systems regulating effort-based processes may have implications for understanding drug abuse, as well as energy-related disorders such as psychomotor slowing, fatigue, or anergia in depression
An overview of point-of-care ultrasound for soft tissue and musculoskeletal applications in the emergency department
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