Sökning: "absence presence"

Visar resultat 21 - 25 av 713 avhandlingar innehållade orden absence presence.

  1. 21. Towards Understanding of Determinants of Physicians’ Sick-listing Practice and their Interrelations : A Population-based Epidemiological Study

    Författare :Britt Arrelöv; Kurt Svärdsudd; Lars Borgquist; Brommels Mats; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Medicine; sick-listing; sickness absence; clinical decision-making; physician; epidemiology; Medicin; Dermatology and venerology; clinical genetics; internal medicine; Dermatologi och venerologi; klinisk genetik; invärtesmedicin; Family Medicine; allmänmedicin;

    Sammanfattning : Physicians are supposed to act as sick-listing experts and they possess a role as gate-keepers to the social insurance system. Earlier studies have demonstrated variation between physicians and physician categories regarding sick-listing practice. LÄS MER

  3. 22. From behaviour to genes: anti-predator responses of brown trout (Salmo trutta) under winter conditions

    Författare :Karl Filipsson; Eva Bergman; Ann Erlandsson; Martin Österling; Johan Watz; Stefán Óli Steingrímsson; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; burbot; climate change; cortisol; diel behaviour; gene expression; HPI axis; light; mRNA; piscivorous; poikilotherm; predator; salmonid; stream; stress; temperature; thermal; winter behaviour; Biology; Biologi;

    Sammanfattning : Temperature has major effects on the performance of poikilotherms. In encounters with predators, low winter temperatures constrain predator detection and escape capabilities in prey fishes. LÄS MER

  4. 23. Atmospheric corrosion of Mg and MgAl alloys – characterization and mechanisms

    Författare :Mehrdad Shahabi Navid; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EDX; CO2; XPS; Mg and MgAl alloys; NaCl; Atmospheric corrosion; Characterization; 3D imaging; SEM; BIB; Thin film; FTIR; XRD; Pitting; Interference microscopy; FIB;

    Sammanfattning : The atmospheric corrosion of Mg and MgAl alloys was investigated. Corrosion tests were performed in the laboratory under controlled environment. CP Mg, AM50 and AZ91 samples were exposed at 95% RH and 22°C in the presence and in the absence of 400 ppm CO2 for 24 h to 672 h. The passive film was characterized by means of XPS, FTIR, AES and XRD. LÄS MER

  5. 24. Fine stream wood : effects on drift and brown trout (Salmo trutta) growth and behaviour

    Författare :Åsa Enefalk; Eva Bergman; Anders Nilsson; Stanley Gregory; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stream fish; wood; salmonid; trout; aquatic invertebrates; behaviour; sheltering; Biology; Biologi;

    Sammanfattning : Stream ecosystems and their riparian zones have previously been regarded as two different ecosystems, linked through numerous reciprocal subsidies. Today, ecologists agree that the stream and the riparian zone should be regarded as one system, the stream-riparian ecosystem, which is characterised largely by the subsidies between land and water. LÄS MER

  7. 25. Mechanisms behind pH changes by plant roots and shoots caused by elevated concentration of toxic elements

    Författare :Muhammad Tariq Javed; Maria Greger; Sylvia Lindberg; Marinus L. Otte; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Elodea canadensis; Eriophorum angustifolium; fluorescence microscopy; mechanisms; metals and metalloid; pH changes; protoplasts; phytofiltration; phytostabilization; root exudates; Plant Physiology; växtfysiologi;

    Sammanfattning : Toxic elements are present in polluted water from mines, industrial outlets, storm water etc. Wetland plants take up toxic elements and increase the pH of the medium. In this thesis was investigated how the shoots of submerged plants and roots of emergent plants affected the pH of the surrounding water in the presence of free toxic ions. LÄS MER