1,589 research outputs found

    Blue and purple Labour challenges to the welfare state: How should 'statist' social democrats respond?

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    This article explores two influential strands of thinking about the welfare state, Blue Labour and Purple Labour, that have emerged following New Labour's defeat at the 2010 General Election. It is argued that although both of these new approaches raise some important issues about the relational and associational dimensions of social welfare as well as diversity and pluralism, those committed to universal and egalitarian goals should not abandon the ‘statist’ social democratic approach to the welfare state

    Some unusual natural areas in Illinois

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    Bibliography: p. 42-43

    Experimental Analysis of Functional Variation within Protein Families: Receiver Domain Autodephosphorylation Kinetics

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    ABSTRACT Plants and microorganisms use two-component signal transduction systems (TCSs) to mediate responses to environmental stimuli. TCSs mediate responses through phosphotransfer from a conserved histidine on a sensor kinase to a conserved aspartate on the receiver domain of a response regulator. Typically, signal termination occurs through dephosphorylation of the receiver domain, which can catalyze its own dephosphorylation. Despite strong structural conservation between receiver domains, reported autodephosphorylation rate constants ( k dephos ) span a millionfold range. Variable receiver domain active-site residues D + 2 and T + 2 (two amino acids C terminal to conserved phosphorylation site and Thr/Ser, respectively) influence k dephos values, but the extent and mechanism of influence are unclear. We used sequence analysis of a large database of naturally occurring receiver domains to design mutant receiver domains for experimental analysis of autodephosphorylation kinetics. When combined with previous analyses, k dephos values were obtained for CheY variants that contained D + 2/T + 2 pairs found in 54% of receiver domain sequences. Tested pairs of amino acids at D + 2/T + 2 generally had similar effects on k dephos in CheY, PhoB N , or Spo0F. Acid or amide residues at D + 2/T + 2 enhanced k dephos . CheY variants altered at D + 2/T + 2 exhibited rate constants for autophosphorylation with phosphoramidates and autodephosphorylation that were inversely correlated, suggesting that D + 2/T + 2 residues interact with aspects of the ground or transition states that differ between the two reactions. k dephos of CheY variants altered at D + 2/T + 2 correlated significantly with k dephos of wild-type receiver domains containing the same D + 2/T + 2 pair. Additionally, particular D + 2/T + 2 pairs were enriched in different response regulator subfamilies, suggesting functional significance. IMPORTANCE One protein family, defined by a conserved domain, can include hundreds of thousands of known members. Characterizing conserved residues within a conserved domain can identify functions shared by all family members. However, a general strategy to assess features that differ between members of a family is lacking. Fully exploring the impact of just two variable positions within a conserved domain could require assessment of 400 (i.e., 20 × 20) variants. Instead, we created and analyzed a nonredundant database of receiver domain sequences. Five percent of D + 2/T + 2 pairs were sufficient to represent 50% of receiver domain sequences. Using protein sequence analysis to prioritize mutant choice made it experimentally feasible to extensively probe the influence of positions D + 2 and T + 2 on receiver domain autodephosphorylation kinetics

    Sensory Response System of Social Behavior Tied to Female Reproductive Traits

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    Honey bees display a complex set of anatomical, physiological, and behavioral traits that correlate with the colony storage of surplus pollen (pollen hoarding). We hypothesize that the association of these traits is a result of pleiotropy in a gene signaling network that was co-opted by natural selection to function in worker division of labor and foraging specialization. By acting on the gene network, selection can change a suite of traits, including stimulus/response relationships that affect individual foraging behavior and alter the colony level trait of pollen hoarding. The 'pollen-hoarding syndrome' of honey bees is the best documented syndrome of insect social organization. It can be exemplified as a link between reproductive anatomy (ovary size), physiology (yolk protein level), and foraging behavior in honey bee strains selected for pollen hoarding, a colony level trait. The syndrome gave rise to the forager-Reproductive Ground Plan Hypothesis (RGPH), which proposes that the regulatory control of foraging onset and foraging preference toward nectar or pollen was derived from a reproductive signaling network. This view was recently challenged. To resolve the controversy, we tested the associations between reproductive anatomy, physiology, and stimulus/response relationships of behavior in wild-type honey bees.Central to the stimulus/response relationships of honey bee foraging behavior and pollen hoarding is the behavioral trait of sensory sensitivity to sucrose (an important sugar in nectar). To test the linkage of reproductive traits and sensory response systems of social behavior, we measured sucrose responsiveness with the proboscis extension response (PER) assay and quantified ovary size and vitellogenin (yolk precursor) gene expression in 6-7-day-old bees by counting ovarioles (ovary filaments) and by using semiquantitative real time RT-PCR. We show that bees with larger ovaries (more ovarioles) are characterized by higher levels of vitellogenin mRNA expression and are more responsive to sucrose solutions, a trait that is central to division of labor and foraging specialization.Our results establish that in wild-type honey bees, ovary size and vitellogenin mRNA level covary with the sucrose sensory response system, an important component of foraging behavior. This finding validates links between reproductive physiology and behavioral-trait associations of the pollen-hoarding syndrome of honey bees, and supports the forager-RGPH. Our data address a current evolutionary debate, and represent the first direct demonstration of the links between reproductive anatomy, physiology, and behavioral response systems that are central to the control of complex social behavior in insects

    Increased Frequency of the MZ Phenotype of Alpha-l-Protease Inhibitor in Juvenile Chronic Polyarthritis

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    Pi phenotypes of alpha-1-protease inhibitor were determined by isoelectric focusing and print immunofixation in 96 English children suffering from juvenile chronic polyarthritis. A significantly increased frequency of the MZ phenotype (10.41%) was found in comparison with a geographically matched control population (1.6%). The results of this study suggest that the possession of a Z-deficient allele of alpha-l-protease inhibitor could be a predisposing, aggravating, or perpetuating factor in the articular damage occurring in juvenile chronic polyarthritis

    Superstars and Giant Gravitons in M-theory

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    Following hep-th/0109127, we show that a certain class of BPS naked singularities (superstars) found in compactifications of M-theory can be interpreted as being composed of giant gravitons. More specifically, we study superstars which are asymptotically AdS_7 x S^4 and AdS_4 x S^7 and show that these field configurations can be interpreted as being sourced by continuous distributions of spherical M2- and M5-branes, respectively, which carry internal momenta and have expanded on the spherical component of the space-time.Comment: 13 page

    Genomics of a Metamorphic Timing QT:: Met1 Maps to a Unique Genomic Position and Regulates Morph and Species-Specific Patterns of Brain Transcription

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    Very little is known about genetic factors that regulate life history transitions during ontogeny. Closely related tiger salamanders (Ambystoma species complex) show extreme variation in metamorphic timing, with some species foregoing metamorphosis altogether, an adaptive trait called paedomorphosis. Previous studies identified a major effect quantitative trait locus (met1) for metamorphic timing and expression of paedomorphosis in hybrid crosses between the biphasic Eastern tiger salamander (Ambystoma tigrinum tigrinum) and the paedomorphic Mexican axolotl (Ambystoma mexicanum).We used existing hybrid mapping panels and a newly created hybrid cross to map the met1 genomic region and determine the effect of met1 on larval growth, metamorphic timing, and gene expression in the brain. We show that met1 maps to the position of a urodele-specific chromosome rearrangement on linkage group 2 that uniquely brought functionally associated genes into linkage. Further more, we found that more than 200 genes were differentially expressed during larval development as a function of met1 genotype. This list of differentially expressed genes is enriched for proteins that function in the mitochondria, providing evidence of a link between met1, thyroid hormone signaling, and mitochondrial energetics associated with metamorphosis. Finally, we found that met1 significantly affected metamorphic timing in hybrids, but not early larval growth rate. Collectively, our results show that met1 regulates species and morph-specific patterns of brain transcription and life history variation

    Do genetic structure and landscape heterogeneity impact color morph frequency in a polymorphic salamander?

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    Landscape heterogeneity plays an important role in population structure and divergence, particularly for species with limited vagility. Here, we used a landscape genetic approach to identify how landscape and environmental variables affect genetic structure and color morph frequency in a polymorphic salamander. The eastern red- backed salamander, Plethodon cinereus, is widely distributed in northeastern North America and contains two common color morphs, striped and unstriped, that are divergent in ecology, behavior, and physiology. To quantify population structure, rates of gene flow, and genetic drift, we amplified 10 microsatellite loci from 648 individuals across 28 sampling localities. This study was conducted in northern Ohio, where populations of P. cinereus exhibit an unusually wide range of morph frequency variation. To test whether genetic distance was more correlated with morph frequency, elevation, canopy cover, waterways, ecological niche or geographic distance, we used resistance distance and least cost path analyses. We then examined whether landscape and environmental variables, genetic distance or geographic distance were correlated with variation in morph frequency. Tests for population structure revealed three genetic clusters across our sampling range, with one cluster monomorphic for the striped morph. Rates of gene flow and genetic drift were low to moderate across sites. Genetic distance was most correlated with ecological niche, elevation and a combination of landscape and environmental variables. In contrast, morph frequency variation was correlated with waterways and geographic distance. Thus, our results suggest that selection is also an important evolutionary force across our sites, and a balance between gene flow, genetic drift and selection interact to maintain the two color morphs

    Using a comparative approach to investigate the relationship between landscape and genetic connectivity among woodland salamander population

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    For many amphibian species, reduced landscape connectivity results in reduced genetic connectivity among populations. However, large efective population sizes (Ne) slow the rate of genetic drift, causing subdivided populations to remain genetically similar despite little gene fow among them. Therefore, it is important to address the combined efects of Ne and matrix permeability to quantify the relative importance of gene fow and genetic drift on isolated amphibian populations. We applied a landscape genetic approach to investigate how patterns of gene fow (m), Ne (inferred via θ) and genetic difer- entiation difer among Eastern Red-backed Salamander (Plethodon cinereus) populations in a fragmented landscape (n=4) compared to a continuous forest (n=4). We assayed a panel of 10 microsatellite markers for population genetic analyses. Additionally, we constructed and validated a distribution model to generate resistance surfaces for examining the relation- ship between landscape connectivity, m, θ, and genetic diferentiation (FST) using maximum-likelihood population-efects models (MLPE). Populations in continuous habitat were undiferentiated, whereas fragmented populations exhibited genetic structure driven by a single population. Results of the MLPE models in the fragmented landscape revealed spatial variation in θ as the best predictor of pairwise FST, followed by estimates of m, suggesting migration-drift interactions have a stronger infuence on genetic diferentiation than matrix permeability. Moreover, model coefcients for landscape resistance were comparable between landscapes. Overall, our results provide insight as to how the interaction of gene fow and genetic drift shapes population structure for a dispersal-limited species within a predominately anthropogenic landscape
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