38 research outputs found

    Conditions for successful range shifts under climate change -the role of species dispersal and landscape configuration

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Aim: Ongoing climate change is currently modifying the geographical location of areas that are climatically suitable for species. Understanding a species’ ability to successfully shift its geographical range would allow us to assess extinction risks and predict future community compositions. We investigate how habitat configuration impedes or promotes climate-driven range shifts, given different speeds of climate change and dispersal abilities. Location: Theoretical, but illustrated with European examples. Methods: We model how a species’ ability to track a directional shift in climatic conditions is affected by: i) species’ dispersal abilities; ii) speed of climatic shift; and iii) spatial arrangement of the habitat. Our modeling framework includes within and between-patch population dynamics and uses ecologically realistic habitat distributions and dispersal scenarios (verified with data from a set of European mammal species), and, as such, is an improvement of classical range shift models. Results: In landscapes with a homogeneous distribution of suitable habitats, all but the least dispersive species will be able to range shift. However, species with high dispersal ability will have lower population densities after range shift. In heterogeneous landscapes species’ ability to range shift is far more variable and heavily dependent on the habitat configuration. This means that landscape configuration in combination with the speed of climate change and species dispersal abilities give rise to non-linear effects on population sizes and survival after a climatic shift. Main conclusions: : Our analyses point out the importance of accounting for the interplay of species dispersal and the landscape configuration when estimating future climate impact on species. These results link ecologically important attributes of both species and their landscapes to outcomes of species range shift, and thereby long-term persistence of ecological communities.This research was funded by the ERA-Net BiodivERsA, part of the 2011 BiodivERsA call for research proposals. RE and A.Es acknowledge the ERA-Net BiodivERsA, with the national funder FCT, through the project BIODIVERSA/00003/2011. A.Ek. acknowledge funding from Swedish Research Council grant number 2016-04919. A.Es. has a postdoctoral contract funded by the project CN-17-022 (Principado de Asturias, Spain)

    Troubled social background of male anabolic-androgenic steroid abusers in treatment

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    <p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the social background and current social situation of male abusers of anabolic-androgenic steroids (AAS).</p> <p>Methods</p> <p>We compared thirty-four AAS-abusing patients from an Addiction Centre (AC) with two groups, 18 users and 259 non-users of AAS from a public gym in Orebro, Sweden. The study is based on semi-structured interviews and questionnaires.</p> <p>Results</p> <p>Histories of a troubled childhood as well as current social disadvantage were both more frequent among the AAS users. Users also reported poor relationships with their parents and almost half of them had experienced physical or mental abuse. The AC group's experiences from school were mostly negative, and included concentration problems, boredom and learning difficulties. Their current circumstance included abuse of other drugs, battering of spouses and other criminality such as assault, illegal possession of weapons and theft.</p> <p>Conclusion</p> <p>In conclusion, this study shows that abusers of AAS often have a troubled social background. This underlines the importance of making a thorough social assessment as a part of the treatment programme. The results of the study may help in directing appropriate questions relevant to the abuse of AAS.</p
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