324 research outputs found
Ethnicity and obesity: evidence of implicit work performance stereotypes in Sweden
Using the Implicit Association Test, we investigate whether employers and students possess implicit and explicit negative attitudes and implicit performance stereotypes toward Arab-Muslim men relative to native Swedish men. We also examine if employers and students have implicit and explicit performance stereotypes toward obese individuals relative to people of normal weight. The results demonstrate that employers and students both implicitly and explicitly associate Arab-Muslim men with less work performance. Also, they have more implicit negative attitudes toward this ethnic group. Obese individuals are both implicitly and explicitly associated with less work performance compared with normal-weight individuals.Implicit; attitudes; stereotypes; discrimination; ethnicity; obesity
Comparative Population Genetics of Two Invading Ticks: Evidence of the Ecological Mechanisms Underlying Tick Range Expansions
Two species of ixodid tick, Ixodes affinis Neumann and Amblyomma maculatum Koch, are simultaneously expanding their ranges throughout the mid-Atlantic region of the US. Although we have some understanding of the ecology and life history of these species, the ecological mechanisms governing where and how new populations establish and persist are unclear. To assess population connectivity and ancestry, we sequenced a fragment of the 16S mitochondrial rRNA gene from a representative sample of individuals of both species from populations throughout the eastern US. We found that despite overlapping host preferences throughout ontogeny, each species exhibited very different genetic and geographic patterns of population establishment and connectivity. I. affinis was of two distinct mitochondrial clades, with a clear geographic break separating northern and southern populations. Both I. affinis populations showed evidence of recent expansion, although the southern population was more genetically diverse, indicating a longer history of establishment. A. maculatum exhibited diverse haplotypes that showed no significant relationship with geographic patterns and little apparent connectivity between sites. Heteroplasmy was also observed in the 16S mitochondrial rRNA gene in 3.5% of A. maculatum individuals. Genetic evidence suggests that these species rely on different key life stages to successfully disperse into novel environments, and that host vagility, habitat stability and habitat connectivity all play critical roles in the establishment of new tick populations
Non-radioactive in situ Hybridization Protocol Applicable for Norway Spruce and a Range of Plant Species
The high-throughput expression analysis technologies available today give scientists an overflow of expression profiles but their resolution in terms of tissue specific expression is limited because of problems in dissecting individual tissues. Expression data needs to be confirmed and complemented with expression patterns using e.g. in situ hybridization, a technique used to localize cell specific mRNA expression. The in situ hybridization method is laborious, time-consuming and often requires extensive optimization depending on species and tissue. In situ experiments are relatively more difficult to perform in woody species such as the conifer Norway spruce (Picea abies). Here we present a modified DIG in situ hybridization protocol, which is fast and applicable on a wide range of plant species including P. abies. With just a few adjustments, including altered RNase treatment and proteinase K concentration, we could use the protocol to study tissue specific expression of homologous genes in male reproductive organs of one gymnosperm and two angiosperm species; P. abies, Arabidopsis thaliana and Brassica napus. The protocol worked equally well for the species and genes studied. AtAP3 and BnAP3 were observed in second and third whorl floral organs in A. thaliana and B. napus and DAL13 in microsporophylls of male cones from P. abies. For P. abies the proteinase K concentration, used to permeablize the tissues, had to be increased to 3 g/ml instead of 1 g/ml, possibly due to more compact tissues and higher levels of phenolics and polysaccharides. For all species the RNase treatment was removed due to reduced signal strength without a corresponding increase in specificity. By comparing tissue specific expression patterns of homologous genes from both flowering plants and a coniferous tree we demonstrate that the DIG in situ protocol presented here, with only minute adjustments, can be applied to a wide range of plant species. Hence, the protocol avoids both extensive species specific optimization and the laborious use of radioactively labeled probes in favor of DIG labeled probes. We have chosen to illustrate the technically demanding steps of the protocol in our film
Fortuitous insights into the ecology of a recently charted deep-sea hydrothermal vent, using snails’ feet.
Evaluating Recruitment Contribution Of A Selectively Bred Aquaculture Line Of The Oyster, Crassostrea Virginica Used In Restoration Efforts
Severe over-fishing, habitat degradation, and recent disease impacts have devastated the eastern oyster (Crassostrea virginica) fisherey in the Chesapeake Bay. Several restoration efforts are in progress, including the unconventional approach of seeding reefs with an aquaculture strain selected for disease resistance and fast growth in hopes of mitigating the negative effects of diseases and low census numbers. Supplementation of four sites (The Great Wicomico, Lynnhaven, York and Elizabeth Rivers) examined in this study totaled approximatedly 18,500,000 aquaculture oysters from 2002 to 2006. We collected locally recruited offspring (n = 6517) from 2002 to 2006 at these sites to determine if reproduction by the transplanted oysters produced detectable contributions to recruitment by examining the frequency of a composite mitochondrial haplotype that occurs at high frequencies in this aquaculture strain but is rare in wild Chesapeake Bay oysters. The estimated frequency of this haplotype in locally recruited oysters (average 1.4%, SD = 0.9) was compared with the average frequencies found in the hatchery produced (35%, SD = 12.8) and wild (1.2%, SD = 0.9) oysters, but we were unable to refute the null-hypothesis that population supplementation made no contribution to recruitment. We discuss five nonmutually exclusive explanations for the limited impact of supplementation, including unequal sex-ratio, predation, flushing, relative scale, and aquaculture selection. We argue that predation, relative scale and aquaculture selection are the likely reasons for the limited contribution made by aquaculture oysters used for population supplementation
A Primer on the benefits of differential treatment analysis when predicting discriminatory behavior
A central question in social psychology is to what extent individual differences in attitudes, prejudices, and stereotypes can predict discriminatory behavior. This is often studied by simply regressing a measure of behavior toward a single group (e.g., behavior toward Black people only) onto the predictors (e.g., attitude measures). In the present paper, we remind researchers that an analysis focusing on predicting the differential treatment (e.g., behavior towards Black people vs. White people) has a higher conceptual validity and will result in more informative effect sizes. The paper is concluded with a list of suggestions for future research on the link between attitudes, prejudices, stereotypes and discrimination
Fragment-Based Discovery of Subtype-Selective Adenosine Receptor Ligands from Homology Models
Fragment-based lead discovery (FBLD) holds great promise for drug discovery, but applications to G protein-coupled receptors (GPCRs) have been limited by a lack of sensitive screening techniques and scarce structural information. If virtual screening against homology models of GPCRs could be used to identify fragment ligands, FBLD could be extended to numerous important drug targets and contribute to efficient lead generation. Access to models of multiple receptors may further enable the discovery of fragments that bind specifically to the desired target. To investigate these questions, we used molecular docking to screen >500?000 fragments against homology models of the A3 and A1 adenosine receptors (ARs) with the goal to discover A3AR-selective ligands. Twenty-one fragments with predicted A3AR-specific binding were evaluated in live-cell fluorescence-based assays; of eight verified ligands, six displayed A3/A1 selectivity, and three of these had high affinities ranging from 0.1 to 1.3 ?M. Subsequently, structure-guided fragment-to-lead optimization led to the identification of a >100-fold-selective antagonist with nanomolar affinity from commercial libraries. These results highlight that molecular docking screening can guide fragment-based discovery of selective ligands even if the structures of both the target and antitarget receptors are unknown. The same approach can be readily extended to a large number of pharmaceutically important targets
The spatial scale of genetic subdivision in populations of Ifremeria nautilei, a hydrothermal-vent gastropod from the southwest Pacific
<p>Abstract</p> <p>Background</p> <p>Deep-sea hydrothermal vents provide patchy, ephemeral habitats for specialized communities of animals that depend on chemoautotrophic primary production. Unlike eastern Pacific hydrothermal vents, where population structure has been studied at large (thousands of kilometres) and small (hundreds of meters) spatial scales, population structure of western Pacific vents has received limited attention. This study addresses the scale at which genetic differentiation occurs among populations of a western Pacific vent-restricted gastropod, <it>Ifremeria nautilei</it>.</p> <p>Results</p> <p>We used mitochondrial and DNA microsatellite markers to infer patterns of gene flow and population subdivision. A nested sampling strategy was employed to compare genetic diversity in discrete patches of <it>Ifremeria nautilei </it>separated by a few meters within a single vent field to distances as great as several thousand kilometres between back-arc basins that encompass the known range of the species. No genetic subdivisions were detected among patches, mounds, or sites within Manus Basin. Although <it>I. nautilei </it>from Lau and North Fiji Basins (~1000 km apart) also exhibited no evidence for genetic subdivision, these populations were genetically distinct from the Manus Basin population.</p> <p>Conclusions</p> <p>An unknown process that restricts contemporary gene flow isolates the Manus Basin population of <it>Ifremeria nautilei </it>from widespread populations that occupy the North Fiji and Lau Basins. A robust understanding of the genetic structure of hydrothermal vent populations at multiple spatial scales defines natural conservation units and can help minimize loss of genetic diversity in situations where human activities are proposed and managed.</p
A primer for use of genetic tools in selecting and testing the suitability of set-aside sites protected from deep-sea seafloor massive sulfide mining activities
AbstractSeafloor massive sulfide (SMS) mining will likely occur at hydrothermal systems in the near future. Alongside their mineral wealth, SMS deposits also have considerable biological value. Active SMS deposits host endemic hydrothermal vent communities, whilst inactive deposits support communities of deep water corals and other suspension feeders. Mining activities are expected to remove all large organisms and suitable habitat in the immediate area, making vent endemic organisms particularly at risk from habitat loss and localised extinction. As part of environmental management strategies designed to mitigate the effects of mining, areas of seabed need to be protected to preserve biodiversity that is lost at the mine site and to preserve communities that support connectivity among populations of vent animals in the surrounding region. These “set-aside” areas need to be biologically similar to the mine site and be suitably connected, mostly by transport of larvae, to neighbouring sites to ensure exchange of genetic material among remaining populations. Establishing suitable set-asides can be a formidable task for environmental managers, however the application of genetic approaches can aid set-aside identification, suitability assessment and monitoring. There are many genetic tools available, including analysis of mitochondrial DNA (mtDNA) sequences (e.g. COI or other suitable mtDNA genes) and appropriate nuclear DNA markers (e.g. microsatellites, single nucleotide polymorphisms), environmental DNA (eDNA) techniques and microbial metagenomics. When used in concert with traditional biological survey techniques, these tools can help to identify species, assess the genetic connectivity among populations and assess the diversity of communities. How these techniques can be applied to set-aside decision making is discussed and recommendations are made for the genetic characteristics of set-aside sites. A checklist for environmental regulators forms a guide to aid decision making on the suitability of set-aside design and assessment using genetic tools. This non-technical primer document represents the views of participants in the VentBase 2014 workshop
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