2,406 research outputs found

    Local adaptation with high gene flow: temperature parameters drive adaptation to altitude in the common frog (Rana temporaria)

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    Both environmental and genetic influences can result in phenotypic variation. Quantifying the relative contributions of local adaptation and phenotypic plasticity to phenotypes is key to understanding the effect of environmental variation on populations. Identifying the selective pressures that drive divergence is an important, but often lacking, next step. High gene flow between high- and low-altitude common frog (Rana temporaria) breeding sites has previously been demonstrated in Scotland. The aim of this study was to assess whether local adaptation occurs in the face of high gene flow and to identify potential environmental selection pressures that drive adaptation. Phenotypic variation in larval traits was quantified in R. temporaria from paired high- and low-altitude sites using three common temperature treatments. Local adaptation was assessed using QST–FST analyses, and quantitative phenotypic divergence was related to environmental parameters using Mantel tests. Although evidence of local adaptation was found for all traits measured, only variation in larval period and growth rate was consistent with adaptation to altitude. Moreover, this was only evident in the three mountains with the highest high-altitude sites. This variation was correlated with mean summer and winter temperatures, suggesting that temperature parameters are potentially strong selective pressures maintaining local adaptation, despite high gene flow

    The Formation of Fragments at Corotation in Isothermal Protoplanetary Disks

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    Numerical hydrodynamics simulations have established that disks which are evolved under the condition of local isothermality will fragment into small dense clumps due to gravitational instabilities when the Toomre stability parameter QQ is sufficiently low. Because fragmentation through disk instability has been suggested as a gas giant planet formation mechanism, it is important to understand the physics underlying this process as thoroughly as possible. In this paper, we offer analytic arguments for why, at low QQ, fragments are most likely to form first at the corotation radii of growing spiral modes, and we support these arguments with results from 3D hydrodynamics simulations.Comment: 21 pages, 1 figur

    PARTISIPASI MASYARAKAT DALAM IMPLEMENTASI KEBIJAKAN PEMBAYARAN PAJAK KENDRAAN BERMOTOR DI KOTA JAYAPURA

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    This article aims to analyze public participation in the payment of motor vehicle taxes in the city of Jayapura. Then the supporting and inhibiting factors in community participation in the implementation of motor vehicle tax payment policies in the city of Jayapura. As well as analyzing the efforts made in increasing community participation in the implementation of PKB policies in the city of Jayapura. The research method is descriptive research using a qualitative approach. The phenomenon observed in this research is how the implementation of Regional Regulation No. 7 of 2016 in increasing public participation in the implementation of motor vehicle tax payment policies in the city of Jayapura. The results showed that . All officers and employees follow the rules or legal basis of the police and their main duties and functions (duties, principals and functions) according to applicable regulations. However, in collecting motor vehicle taxes there are problems, but all of them must be normally resolved by the UPPD Samsat Kota Jayapura office. Supporting factors include supporting factors internally and externally from the support of the community and other relevant stakeholders. while the inhibiting factors are the level of compliance of the policy target groups, both supporting resources and HR personnel owned. Then, the efforts that need to be done are Optimizing socialization, Optimizing advertising / promotions, Maximizing services, Revitalizing traffic orderly areas, Conducting raids, Increasing infrastructure support, and Providing officer allowances

    Braidings of Tensor Spaces

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    Let VV be a braided vector space, that is, a vector space together with a solution R^End(VV)\hat{R}\in {\text{End}}(V\otimes V) of the Yang--Baxter equation. Denote T(V):=kVkT(V):=\bigoplus_k V^{\otimes k}. We associate to R^\hat{R} a solution T(R^)End(T(V)T(V))T(\hat{R})\in {\text{End}}(T(V)\otimes T(V)) of the Yang--Baxter equation on the tensor space T(V)T(V). The correspondence R^T(R^)\hat{R}\rightsquigarrow T(\hat{R}) is functorial with respect to VV.Comment: 10 pages, no figure

    Роздуми про музичну бібліографію

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    У статті розглянуто особливості розвитку музичної бібліографії в Україні – від доби “радянського часу” до сучасності. В даному контексті висвітлюється науковий доробок у цій царині А. І. Мухи.В статье рассмотрены особенности развития музыкальной библиографии в Украине, начиная с эпохи “советского времени” до современного этапа. В данном контексте освещено научное наследие в этой области А. И. Мухи.The peculiarities of music bibliography development in the Ukraine are investigated in the article (from epoch “Soviet Union” to modern period of time). Connected with music bibliography some books by A. Mukha are examined in this context

    Implementing a Secure Annotation Service

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    Annotation systems enable "value-adding" to digital resources by the attachment of additional data in the form of comments, explanations, references, reviews, corrections and other types of external, subjective remarks. They facilitate group discourse and capture collective intelligence by enabling communities to attach and share their views on particular data and documents accessible over the Web. Annotation systems vary greatly with regard to the types of content they annotate, the extent of collaboration and sharing they allow and the communities which they serve. However within many applications, there is a need to restrict access to the annotations to a particular group of trusted users - in order to protect intellectual property rights or personal privacy. This paper describes a secure, open source annotation system that we have developed that uses Shibboleth and XACML to identify and authenticate users and restrict their access to annotations stored on an Annotea server

    Effective Actions near Singularities

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    We study the heterotic string compactified on K3 x T^2 near the line T=U, where the effective action becomes singular due to an SU(2) gauge symmetry enhancement. By `integrating in' the light W^\pm vector multiplets we derive a quantum corrected effective action which is manifestly SU(2) invariant and non-singular. This effective action is found to be consistent with a residual SL(2,Z) quantum symmetry on the line T=U. In an appropriate decompactification limit, we recover the known SU(2) invariant action in five dimensions.Comment: 33 pages, LaTeX. v2: cosmetic correction on titlepage. v3: references and note adde

    Special relativity constraints on the effective constituent theory of hybrids

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    We consider a simplified constituent model for relativistic strong-interaction decays of hybrid mesons. The model is constructed using rules of renormalization group procedure for effective particles in light-front quantum field theory, which enables us to introduce low-energy phenomenological parameters. Boost covariance is kinematical and special relativity constraints are reduced to the requirements of rotational symmetry. For a hybrid meson decaying into two mesons through dissociation of a constituent gluon into a quark-anti-quark pair, the simplified constituent model leads to a rotationally symmetric decay amplitude if the hybrid meson state is made of a constituent gluon and a quark-anti-quark pair of size several times smaller than the distance between the gluon and the pair, as if the pair originated from one gluon in a gluonium state in the same effective theory.Comment: 11 pages, 5 figure

    Polio vaccination and Chronic Fatigue Syndrome

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    Background:- Previous research has suggested that enteroviruses may be implicated in the development and persistence of Chronic Fatigue Syndrome (CFS). One method of investigating this topic has been to use a polio vaccination challenge, and a previous study showed that CFS patients had more shedding than healthy controls. There was no effect of the vaccination on the clinical condition or wellbeing of the CFS patients. Methods:- In the previous study, the control group were more likely to have had a recent booster vaccination. This was controlled in the present study, where 18 CFS patients were randomly assigned to vaccination or placebo conditions. Nine healthy volunteers were also given the polio vaccination. Results:- The results confirmed that vaccination had no negative effects on the CFS group. Although there was more virus shedding in the CFS polio group than in the control polio group, this difference was not significant. Conclusion:- This study confirms that polio vaccination is not contraindicated in CFS patients but could not confirm that they are more susceptible to enterovirus infection
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