3,142 research outputs found

    Niche evolution reveals disparate signatures of speciation in the ‘great speciator’ (white‐eyes, Aves: Zosterops )

    Get PDF
    ACKNOWLEDGEMENTS J.O.E. and L.L. coordinated and secured project funding with the support from J.S.C.; we thank AT Peterson and CH Graham and two reviewers for critical feedback on earlier stages of the manuscript. The project was funded by the Research Foundation – Flanders (FWO; 1527918N & G042318N). J.O.E. received additional funds by an FWO Postdoctoral Fellowship (12G4317N). The authors declare no conflict of interest. No permits were needed to conduct the re- search presented here. DATA AVAILABILITY STATEMENT All data are available from open source platforms. Raw GBIF.org occurrence data used for this work (as accessed on 21st October 2016) can be accessed through GBIF Occurrence Download http://doi.org/10.15468/dl.erwqs6. We have deposited the prepared data used for this work on FigShare accessible through https://doi.org/10.6084/m9.figshare.13042031.v1 as well as R scripts for data analysis in a GitHub repository accessible through https://github.com/JOEngler/ZostiNicheEvol.Peer reviewedPublisher PD

    Разработка системы управления персоналом шахты «Распадская»

    Get PDF
    Выпускная квалификационная работа содержит 98 страниц, 14 рисунков, 17 таблиц, 2 схемы, 1 диаграмма, 36 использованных источников, 5 приложений. Ключевые слова: система управления персоналом, адаптация персонала, обучение персонала, привлечение новых сотрудников, организационная культура, отбор персонала. Объектом исследования является шахта Распадская. Цель работы — исследовать теоретические, практические и методологические основы разработки системы управления персоналом на предприятии. Исследовать процессы адаптации и обучения, сложившиеся на шахте. В процессе исследования проводились исследования теоретических и методологических аспектов системы управления персоналом шахты Распадская.Graduate qualification work consists of 119 pages, 14 figures, 16 tables, 2 schemes, 36 sources, 5 applications. The object of research is the mine Raspadskaya. The target of research – to explore the theoretical, practical and methodological basis for the development of personnel management system in this organization. To explore the processes of adaptation and training in the mine. In the course of researching there were studies of the theoretical and methodological aspects of the personnel management system of the mine Raspadskaya. It was analyzed the current situation in the field of personnel management. According to results of researching this work offers recommendations for the development of personnel management system in the mine Raspadskaya. Degree of implementati

    Guilt averse or reciprocal? Looking at behavioral motivations in the trust game

    Full text link
    For the trust game, recent models of belief-dependent motivations make opposite predictions regarding the correlation between back transfers and secondorder beliefs of the trustor: while reciprocity models predict a negative correlation, guilt-aversion models predict a positive one. This paper tests the hypothesis that the inconclusive results in the previous studies investigating the reaction of trustees to their beliefs are due to the fact that reciprocity and guilt aversion are behaviorally relevant for different subgroups and that their impact cancels out in the aggregate. We find little evidence in support of this hypothesis and conclude that type heterogeneity is unlikely to explain previous results

    Strong anisotropy in surface kinetic roughening: analysis and experiments

    Full text link
    We report an experimental assessment of surface kinetic roughening properties that are anisotropic in space. Working for two specific instances of silicon surfaces irradiated by ion-beam sputtering under diverse conditions (with and without concurrent metallic impurity codeposition), we verify the predictions and consistency of a recently proposed scaling Ansatz for surface observables like the two-dimensional (2D) height Power Spectral Density (PSD). In contrast with other formulations, this Ansatz is naturally tailored to the study of two-dimensional surfaces, and allows to readily explore the implications of anisotropic scaling for other observables, such as real-space correlation functions and PSD functions for 1D profiles of the surface. Our results confirm that there are indeed actual experimental systems whose kinetic roughening is strongly anisotropic, as consistently described by this scaling analysis. In the light of our work, some types of experimental measurements are seen to be more affected by issues like finite space resolution effects, etc. that may hinder a clear-cut assessment of strongly anisotropic scaling in the present and other practical contexts

    Testing the proposed link between cosmic rays and cloud cover

    Full text link
    A decrease in the globally averaged low level cloud cover, deduced from the ISCCP infra red data, as the cosmic ray intensity decreased during the solar cycle 22 was observed by two groups. The groups went on to hypothesise that the decrease in ionization due to cosmic rays causes the decrease in cloud cover, thereby explaining a large part of the presently observed global warming. We have examined this hypothesis to look for evidence to corroborate it. None has been found and so our conclusions are to doubt it. From the absence of corroborative evidence, we estimate that less than 23%, at the 95% confidence level, of the 11-year cycle change in the globally averaged cloud cover observed in solar cycle 22 is due to the change in the rate of ionization from the solar modulation of cosmic rays

    A Modular Cloning System for Standardized Assembly of Multigene Constructs

    Get PDF
    The field of synthetic biology promises to revolutionize biotechnology through the design of organisms with novel phenotypes useful for medicine, agriculture and industry. However, a limiting factor is the ability of current methods to assemble complex DNA molecules encoding multiple genetic elements in various predefined arrangements. We present here a hierarchical modular cloning system that allows the creation at will and with high efficiency of any eukaryotic multigene construct, starting from libraries of defined and validated basic modules containing regulatory and coding sequences. This system is based on the ability of type IIS restriction enzymes to assemble multiple DNA fragments in a defined linear order. We constructed a 33 kb DNA molecule containing 11 transcription units made from 44 individual basic modules in only three successive cloning steps. This modular cloning (MoClo) system can be readily automated and will be extremely useful for applications such as gene stacking and metabolic engineering

    A Multiwell Platform for Studying Stiffness-Dependent Cell Biology

    Get PDF
    Adherent cells are typically cultured on rigid substrates that are orders of magnitude stiffer than their tissue of origin. Here, we describe a method to rapidly fabricate 96 and 384 well platforms for routine screening of cells in tissue-relevant stiffness contexts. Briefly, polyacrylamide (PA) hydrogels are cast in glass-bottom plates, functionalized with collagen, and sterilized for cell culture. The Young's modulus of each substrate can be specified from 0.3 to 55 kPa, with collagen surface density held constant over the stiffness range. Using automated fluorescence microscopy, we captured the morphological variations of 7 cell types cultured across a physiological range of stiffness within a 384 well plate. We performed assays of cell number, proliferation, and apoptosis in 96 wells and resolved distinct profiles of cell growth as a function of stiffness among primary and immortalized cell lines. We found that the stiffness-dependent growth of normal human lung fibroblasts is largely invariant with collagen density, and that differences in their accumulation are amplified by increasing serum concentration. Further, we performed a screen of 18 bioactive small molecules and identified compounds with enhanced or reduced effects on soft versus rigid substrates, including blebbistatin, which abolished the suppression of lung fibroblast growth at 1 kPa. The ability to deploy PA gels in multiwell plates for high throughput analysis of cells in tissue-relevant environments opens new opportunities for the discovery of cellular responses that operate in specific stiffness regimes

    A p-adic analogue of Siegel's Theorem on sums of squares

    Get PDF
    Siegel proved that every totally positive element of a number field K is the sum of four squares, so in particular the Pythagoras number is uniformly bounded across number fields. The p ‐adic Kochen operator provides a p ‐adic analogue of squaring, and a certain localisation of the ring generated by this operator consists of precisely the totally p ‐integral elements of K . We use this to formulate and prove a p ‐adic analogue of Siegel's theorem, by introducing the p ‐Pythagoras number of a general field, and showing that this number is uniformly bounded across number fields. We also generally study fields with finite p ‐Pythagoras number and show that the growth of the p ‐Pythagoras number in finite extensions is bounded
    corecore