221 research outputs found

    Entrepreneurship, agency frictions and redistributive capital taxation

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    Motivated by the observation that among OECD countries redistribution is negatively correlated with entrepreneurial activity, we examine the implications of entrepreneurial financial frictions for optimal linear capital taxation, in a setting where the government is concerned with redistribution. By including financial frictions, we emphasize the effect of a new channel affecting the equity-efficiency trade-off of redistribution: taxes affect the allocative efficiency of capital and, ultimately, total factor productivity. We find that high tax rates are optimal, provided that they are applied to wealth, rather than risky capital. Under plausible parameter values, we find that the optimal tax on risky capital is lower than that on wealth, and roughly in line with current U.S. levels. This suggests welfare gains from taxing only wealth at a higher rate.Othe

    The clarity incentive for issue engagement in campaigns

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    Although parties focus disproportionately on favorable issues in their election campaigns, it is also the case that parties spend much of the ‘short campaign’ addressing the same issues – and especially salient issues. If able to influence the importance of issues for voters through their emphasis, it is puzzling that parties spend any time on unfavourable issue positions. We suggest that while parties prefer to emphasize popular issue positions, they also face an additional incentive to emphasize issues that are salient to voters: clarifying their positions on these issues for sympathetic voters. Leveraging the surprise general election victory of the British Conservative party in 2015—which brought about a hitherto unexpected referendum on EU membership—we show that, consistent with this hypothesis, voter uncertainty is especially costly for parties on salient issues. We formalize this argument using a model of party strategy with endogenous issue salience.Othe

    Capital deaccumulation and the large persistent effects of financial crises

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    In a panel of OECD and emerging economies, I find that banking crises are characterized by larger initial drops in investment than other large recessions and are followed by particularly persistent drops in output. Furthermore, the larger the drop in investment during the crisis, the more persistent the decrease in output subsequently. I present a model to account for these patterns, in which a financial shock temporarily increases the costs of external finance for investing entrepreneurs, leading to a drop in investment and a persistent slump in output and employment. Critical to the model is the distinction between different types of capital with different depreciation rates. Intangible capital and equipment have high depreciation rates, leading these stocks to drop substantially when investment falls during a financial shock. This can cause output and employment to remain low for close to a decade, through the contribution of equipment and intangibles to production and labor demand. I show that the consequences of such a financial shock correspond to several features of the US Great Recession (2008-2014), especially the large drop in equipment and intangible capital. In the model, TFP and government spending shocks do not lead to such large declines in investment or persistent output decreases, so the model is also consistent with the more transitory output drops seen after non-financial recessions, where such shocks may have been more important. ​Othe

    Molecular Characterization of the Onset and Progression of Colitis in Inoculated Interleukin-10 Gene-Deficient Mice: A Role for PPARα

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    The interleukin-10 gene-deficient (Il10−/−) mouse is a model of human inflammatory bowel disease and Ppara has been identified as one of the key genes involved in regulation of colitis in the bacterially inoculated Il10−/− model. The aims were to (1) characterize colitis onset and progression using a histopathological, transcriptomic, and proteomic approach and (2) investigate links between PPARα and IL10 using gene network analysis. Bacterial inoculation resulted in severe colitis in Il10−/− mice from 10 to 12 weeks of age. Innate and adaptive immune responses showed differences in gene expression relating to colitis severity. Actin cytoskeleton dynamics, innate immunity, and apoptosis-linked gene and protein expression data suggested a delayed remodeling process in 12-week-old Il10−/− mice. Gene expression changes in 12-week-old Il10−/− mice were related to PPARα signaling likely to control colitis, but how PPARα activation might regulate intestinal IL10 production remains to be determined

    The MtrAB two-component system controls antibiotic production in Streptomyces coelicolor A3(2

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    MtrAB is a highly conserved two-component system implicated in the regulation of cell division in the Actinobacteria. It coordinates DNA replication with cell division in the unicellular Mycobacterium tuberculosis and links antibiotic production to sporulation in the filamentous Streptomyces venezuelae. Chloramphenicol biosynthesis is directly regulated by MtrA in S. venezuelae and deletion of mtrB constitutively activates MtrA and results in constitutive over-production of chloramphenicol. Here we report that in Streptomyces coelicolor, MtrA binds to sites upstream of developmental genes and the genes encoding ActII-1, ActII-4 and RedZ, which are cluster-situated regulators of the antibiotics actinorhodin (Act) and undecylprodigiosin (Red). Consistent with this, deletion of mtrB switches on the production of Act, Red and streptorubin B, a product of the Red pathway. Thus, we propose that MtrA is a key regulator that links antibiotic production to development and can be used to upregulate antibiotic production in distantly related streptomycetes

    Is Persistent Motor or Vocal Tic Disorder a Milder Form of Tourette Syndrome?

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    BACKGROUND: Persistent motor or vocal tic disorder (PMVT) has been hypothesized to be a forme fruste of Tourette syndrome (TS). Although the primary diagnostic criterion for PMVT (presence of motor or vocal tics, but not both) is clear, less is known about its clinical presentation. OBJECTIVE: The goals of this study were to compare the prevalence and number of comorbid psychiatric disorders, tic severity, age at tic onset, and family history for TS and PMVT. METHODS: We analyzed data from two independent cohorts using generalized linear equations and confirmed our findings using meta‐analyses, incorporating data from previously published literature. RESULTS: Rates of obsessive–compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) were lower in PMVT than in TS in all analyses. Other psychiatric comorbidities occurred with similar frequencies in PMVT and TS in both cohorts, although meta‐analyses suggested lower rates of most psychiatric disorders in PMVT compared with TS. ADHD and OCD increased the odds of comorbid mood, anxiety, substance use, and disruptive behaviors, and accounted for observed differences between PMVT and TS. Age of tic onset was approximately 2 years later, and tic severity was lower in PMVT than in TS. First‐degree relatives had elevated rates of TS, PMVT, OCD, and ADHD compared with population prevalences, with rates of TS equal to or greater than PMVT rates. CONCLUSIONS: Our findings support the hypothesis that PMVT and TS occur along a clinical spectrum in which TS is a more severe and PMVT a less severe manifestation of a continuous neurodevelopmental tic spectrum disorder. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Societ

    A Multifunctional, Charge-Neutral, Chiral Octahedral M12 L12 Cage.

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    peer reviewedA chiral, octahedral M12 L12 cage, which is charge neutral and contains an internal void of about 2000 Å3 , is reported. The cage was synthesised as an enantiopure complex by virtue of amino-acid-based dicarboxylate ligands, which assemble around copper paddlewheels at the vertices of the octahedron. The cage persists in solution with retention of the fluorescence properties of the parent acid. The solid-state structure contains large pores both within and between the cages, and displays permanent porosity for the sorption of gases with retention of crystallinity. Initial tests show some enantioselectivity of the cage towards guests in solution

    Hundreds of variants clustered in genomic loci and biological pathways affect human height

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    Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.
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