• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 130
  • 40
  • 13
  • 11
  • 10
  • 7
  • 5
  • 4
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 318
  • 139
  • 73
  • 68
  • 61
  • 57
  • 56
  • 42
  • 37
  • 30
  • 28
  • 28
  • 27
  • 25
  • 24
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Elevers stress : En studie på grundskolans senare år om elevers upplevelser av stress och hur de tror att man kan reducera den / Students' stress : A research on students' experience of stress and how to reduce it

Matsson, Annemarie, Albertsson, Kristian, Svensson, Linus January 2008 (has links)
Students’ experience of stress is generally considered to be an isolated problem, caused by school work. Students’ experience of stress at school can also be affected by exterior influences. This research aims to discover what factors Swedish students, age 13 – 16, experience as stressful. It also aims to describe how students believe this stress can be reduced. This project originated from a request from a secondary school. A questionnaire was used to map the different stress factors. Interviews enabled greater understanding of these factors and what students themselves believe can reduce the stress. The gathered material was interpreted in several steps by the use of ad hoc methods. The result shows that half of the students experience stress every week. The main causes are lack of time and demands. They lack “free time”, which enables the body to recover from the stress. The students desire management, including guidance from parents concerning prioritising and setting limits. The school should help the students to develop study techniques. The stress is caused by a feeling of not being able to live up to and deal with own and exterior demands. It can be reduced by planning (enabling “free time”), influence (co-operation), personal development (improvement of self-esteem and identity) and management (guidance, limitations, acceptance and development). / Elevers upplevda stress i skolan ses ofta som ett isolerat problem som framkallas och påverkas under skoltid. Upplevelser av stress i skolan kan även bero på andra faktorer som elever påverkas av utanför skoltid. Studien syftar till att kartlägga olika faktorer som elever i årskurs 7-9 upplever som stressande och hur de tror att stressen kan reduceras. Detta arbete har utgått från en frågeställning som framförts av en skola. En enkät användes för att kartlägga olika stressfaktorer. Intervjuer gav djupare förståelse för de olika stressfaktorerna och hur eleverna tror att den upplevda stressen kan reduceras. Det insamlade materialet tolkades i flera steg med ad hoc-metoder. Resultatet visar att hälften av eleverna känner sig stressade varje vecka. Elevernas största stressfaktorer är tidsbrist och krav. De saknar ”fri tid”, som ger kroppen återhämtning från stress. Eleverna efterlyser ledarskap, hjälp från föräldrar att prioritera och sätta gränser samt att skolan ska utveckla elevernas studietekniker. Stressen orsakas av en känsla att inte kunna leva upp till och hantera egna och omvärldens krav. Reducering av stressen kan ske genom planering (skapande av ”fri tid”), inflytande (samplanering), personlig utveckling (stärkt självkänsla och identitet) och ledarskap (ledning, gränssättning, acceptans och utveckling).
82

Antal copingstrategier och arbetsfaktorer har betydelse för den självskattade stressen

Seydlitz, Kristoffer, Norling, Niklas January 2011 (has links)
Syftet med denna studie var att undersöka hur proffessionstillhörighet och antal copingstrategier respondenterna använder, påverkar skattad stress samt att studera hur arbetsfaktorer påverkar skattad stress. Totalt 84 personer, inom samma organisation, fördelade över två avdelningar med olika arbetsuppgifter - besvarade en enkätundersökning, om stress, coping och arbetsfaktorer. Resultatet av undersökningen visar på en tendens att de respondenter som använder sig av ett fåtal copingstrategier har en lägre skattad stressnivå, (borderline-signifikans), samt att avdelning inte påverkar antalet använda copingstrategier (dvs. ingen interaktionseffekt mellan antalet använda copingstrategier och avdelning). Resultatet visar även att arbetsfaktorerna, vilka delades upp i fyra kategorier; otydlig organisation och konflikter, individuella krav och engagemang, inflytande på arbetet samt konflikt mellan arbete och fritid, predicerar den skattade stressnivån och speciellt individuella krav och engagemang var den kategori som påverkade den skattade stressnivån.Nyckelord: / The purpose of this study was to examine how profession and number of coping strategies used by the respondents affected the estimated stress level and to study the impact on estimated stress level of work factors. 84 persons within the same organization, allocated over two different departments, with different tasks - responded to a survey, about stress, coping and work factors. The results of this study showed a tendency that people who use few coping strategies, showed a lower level of estimated stress (borderline significance), and the number of used coping strategies do not depend on department (i.e. there were no interaction effect between the number of used coping strategies and department). Furthermore, the result showed that work factors, which were categorized into four groups; vague organization, individual demands and commitment, influence over work, and conflict between work and spare time, predict the estimated stress level, especially the individual demands and commitment category affected the estimated stress level.
83

Influence of Invasive Species, Climate Change and Population Density on Life Histories and Mercury Dynamics of Two Coregonus Species

Rennie, Michael 25 September 2009 (has links)
Non-indigenous species can profoundly alter the ecosystems they invade and impact local economies. Growth and body condition declines of commercially fished Great Lakes lake whitefish coincide with the establishment of non-native dreissenid mussels and the cladoceran Bythotrephes longimanus. Declines in lake herring abundance—a key prey item for other commercially important species—have also been reported. Though additional stressors such as climate change may have contributed to changes in coregonid populations, they have not been thoroughly evaluated. Here, I present data that condition and contaminant declines in coregonids are associated with increasing density or warming climate, but growth declines in lake whitefish are likely due to ecosystem changes associated with dreissenids and Bythotrephes. In South Bay, Lake Huron, changes in lake whitefish diet composition and stable isotope signatures were consistent with increased reliance on nearshore resources after dreissenid establishment; lake whitefish occupied shallower habitats and experienced declines in mean diet energy densities post-dreissenid invasion. Growth of South Bay lake whitefish declined after environmental effects were statistically removed, whereas condition declines were explained best by changes in lake whitefish density. Among four lake whitefish populations, growth declined after dreissenids established, but not in uninvaded reference populations. Growth also declined among four lake whitefish populations after the establishment of Bythotrephes relative to reference populations. In contrast with growth, condition of lake whitefish did not change as a result of dreissenid or Bythotrephes invasion. Bioenergetic models revealed that activity rates increased and conversion efficiencies decreased in lake whitefish populations exposed to dreissenids, despite higher consumption rates in populations with dreissenids present. Condition declines among many lake whitefish and lake herring populations (and declines in mercury among herring populations) reflected regional differences and were not related to the presence of Bythotrephes or Mysis relicta. Declines in condition were more pronounced in northwest Ontario populations where climate has changed more dramatically than in southern Ontario. This work suggests that projected range expansions of dreissenid mussels and Bythotrephes will likely affect native fisheries, and their effect on these fisheries may be exacerbated by declining fish condition associated with climate change.
84

Influence of Invasive Species, Climate Change and Population Density on Life Histories and Mercury Dynamics of Two Coregonus Species

Rennie, Michael 25 September 2009 (has links)
Non-indigenous species can profoundly alter the ecosystems they invade and impact local economies. Growth and body condition declines of commercially fished Great Lakes lake whitefish coincide with the establishment of non-native dreissenid mussels and the cladoceran Bythotrephes longimanus. Declines in lake herring abundance—a key prey item for other commercially important species—have also been reported. Though additional stressors such as climate change may have contributed to changes in coregonid populations, they have not been thoroughly evaluated. Here, I present data that condition and contaminant declines in coregonids are associated with increasing density or warming climate, but growth declines in lake whitefish are likely due to ecosystem changes associated with dreissenids and Bythotrephes. In South Bay, Lake Huron, changes in lake whitefish diet composition and stable isotope signatures were consistent with increased reliance on nearshore resources after dreissenid establishment; lake whitefish occupied shallower habitats and experienced declines in mean diet energy densities post-dreissenid invasion. Growth of South Bay lake whitefish declined after environmental effects were statistically removed, whereas condition declines were explained best by changes in lake whitefish density. Among four lake whitefish populations, growth declined after dreissenids established, but not in uninvaded reference populations. Growth also declined among four lake whitefish populations after the establishment of Bythotrephes relative to reference populations. In contrast with growth, condition of lake whitefish did not change as a result of dreissenid or Bythotrephes invasion. Bioenergetic models revealed that activity rates increased and conversion efficiencies decreased in lake whitefish populations exposed to dreissenids, despite higher consumption rates in populations with dreissenids present. Condition declines among many lake whitefish and lake herring populations (and declines in mercury among herring populations) reflected regional differences and were not related to the presence of Bythotrephes or Mysis relicta. Declines in condition were more pronounced in northwest Ontario populations where climate has changed more dramatically than in southern Ontario. This work suggests that projected range expansions of dreissenid mussels and Bythotrephes will likely affect native fisheries, and their effect on these fisheries may be exacerbated by declining fish condition associated with climate change.
85

Hälsosamt förhållningssätt mot stress: En kvalitativ studie om att vara enhetschef inom LSS i Kalmar kommun

Krusell, Magnus, Ruuth, Patrik January 2011 (has links)
Stress is part of everyday life and in the working conditions of the social services in Sweden. Thus each and every person has resources and strategies to cope with those stressors that construct the assumption of stress. The aim of this study was to understand how persons in leading positions of the LSS of Social Services in Kalmar experience and cope with stressors in their leadership and organization and to investigate what factors during working and non-working hours promote health. Influenced by the theoretical approach of Aaron Antonovsky´s Sense of Coherence seven qualitative interviews were conducted with persons in leading positions. They were asked about stressors, coping strategies, resources and health promoting factors that help to cope with stressors. The interviewees stated that stressors like unclear role description and heavy workload are among others a major part of the role as leader. They also stated that the role as a leader was more desirable than being a chief. Coping strategies were found to help control the daily stressors. Factors during working and non-working hours which promote health were found to be important as a factor to gain energy, relaxation and meaningfulness.
86

Interactions Between Environmental Factors and Polycyclic Aromatic Hydrocarbons (PAHs) in Developing Fish: Molecular and Developmental Implications

Fleming, Carrie January 2010 (has links)
<p>Aquatic systems are impacted by a wide variety of natural and anthropogenic stressors. Laboratory studies often focus on impacts of a single stressor, ignoring how these stressors may interact. This dissertation focuses on the interactions between polycyclic aromatic hydrocarbons (PAHs) and two physical stressors (hypoxia and solar radiation). PAHs are ubiquitous environmental pollutants that occur in the environment as complex mixtures, the components of which may interact. Some PAHs are agonists of the aryl hydrocarbon receptor (AhR), which regulates expression of a number of genes (such as CYP1A) involved in metabolism, often of the same compounds that induced the AhR. PAHs that are AhR agonists have been shown to interact synergistically with PAHs that inhibit activity of CYP1A, inducing developmental deformities in fish. AhR shares a dimerization partner, the aryl hydrocarbon receptor nuclear translocator (ARNT), with the protein responsible for regulating hypoxia-induced gene expression, hypoxia-inducible factor 1á (HIF1&alpha;), possibly resulting in competition between the two pathways. Competition would result in decreased induction of CYP1A under hypoxic conditions, possibly resulting in synergistic embryonic toxicity between AhR agonist PAHs and hypoxia. In this dissertation, the results are presented of experiments regarding the occurrence of AhR/HIF1&alpha; crosstalk in fish and the developmental consequences of co-exposure to hypoxia and PAHs. In vitro testing revealed competition for ARNT in which HIF1&alpha; appeared to out-compete AhR. Induction of an AhR-responsive luciferase reporter by several AhR agonists (benzo[a]pyrene (BaP), benzo[k]fluoranthene (BkF), and polychlorinated biphenyl (PCB126)) was reduced under hypoxia and this effect was eliminated by overexpression of ARNT. Induction of a HIF1&alpha;-responsive reporter was unaffected by BkF and PCB126. BaP caused an ARNT-independent decrease in both basal and induced HIF1&alpha; reporter activity. Attempts to verify this crosstalk pattern in vivo revealed that BaP-induced CYP1A expression was further increased under hypoxic conditions. Induction of hypoxia-inducible genes VEGF and LDHa were unaffected by BaP. The effect of hypoxia on CYP1A expression was not repeated with BkF or pyrene (PY) and the exact conditions that result in hypoxic changes in CYP1A expression remain to be determined. Embryonic toxicity in zebrafish (Danio rerio), including pericardial edema, heart malformations, and death were synergistically induced by hypoxia and BaP, BkF or complex, environmentally relevant PAH mixtures. There was no effect of hypoxia on PCB126 toxicity and hypoxia protected from the pericardial edema induced by PY. CYP1A knockdown mimicked the effects of hypoxia on BkF and PY toxicity and even further exacerbated BkF toxicity under hypoxic conditions, suggesting a role for metabolism in the toxicity. Additionally, since two CYP1A inhibitors (fluoranthene (FL) and á-naphthoflavone (ANF)) had been previously reported to interact synergistically with hypoxia, three other CYP1A inhibitors (dibenzothiophene, carbazole and 2-aminoanthracene) were tested. None of them induced toxicity in combination with hypoxia, indicating that CYP1A inhibition was not the reason for the interaction of FL and ANF with hypoxia. </p><p>A second stressor known to interact with PAHs to induce toxicity is solar radiation. While most studies of the effects of solar radiation on PAH toxicity have focused on the effects of UV light on PAHs already absorbed by an organism (photoactivation), less attention has been paid to the toxic effects of photomodified PAHs. We exposed carbazole to ambient sunlight and subsequently exposed developing zebrafish to the resulting mixture. Photo-exposed carbazole caused developmental toxicity including edema, heart malformations, craniofacial malformations and death that were not caused by parent carbazole; these effects were severely exacerbated by hypoxia and significant mortality was also observed. Additionally, photo-exposed carbazole induced expression of CYP1A and GSTp, likely resulting from agonism of the AhR and toxicity of this mixture was alleviated by morpholino knockdown of AhR. Some photoproducts were identified, but none of them appeared to be involved in the toxicity or supposed AhR induction observed with photoexposed carbazole. The results of these experiments underscore the importance of consideration of the interactive effects of physical and chemical stressors when assessing risks to wildlife populations inhabiting polluted areas.</p> / Dissertation
87

個人の集団透過性に関する構成概念妥当性の検証

黒川, 雅幸, 吉田, 俊和, KUROKAWA, Masayuki, YOSHIDA, Toshikazu 28 December 2007 (has links)
No description available.
88

中学生における学校ストレスと自己価値の相互作用についての縦断的研究

西野, 泰代, NISHINO, Yasuyo 28 December 2007 (has links)
No description available.
89

Elevers stress : En studie på grundskolans senare år om elevers upplevelser av stress och hur de tror att man kan reducera den / Students' stress : A research on students' experience of stress and how to reduce it

Matsson, Annemarie, Albertsson, Kristian, Svensson, Linus January 2008 (has links)
<p>Students’ experience of stress is generally considered to be an isolated problem, caused by school work. Students’ experience of stress at school can also be affected by exterior influences.</p><p>This research aims to discover what factors Swedish students, age 13 – 16, experience as stressful. It also aims to describe how students believe this stress can be reduced. This project originated from a request from a secondary school. A questionnaire was used to map the different stress factors. Interviews enabled greater understanding of these factors and what students themselves believe can reduce the stress. The gathered material was interpreted in several steps by the use of ad hoc methods.</p><p>The result shows that half of the students experience stress every week. The main causes are lack of time and demands. They lack “free time”, which enables the body to recover from the stress. The students desire management, including guidance from parents concerning prioritising and setting limits. The school should help the students to develop study techniques. The stress is caused by a feeling of not being able to live up to and deal with own and exterior demands. It can be reduced by planning (enabling “free time”), influence (co-operation), personal development (improvement of self-esteem and identity) and management (guidance, limitations, acceptance and development).</p> / <p>Elevers upplevda stress i skolan ses ofta som ett isolerat problem som framkallas och påverkas under skoltid. Upplevelser av stress i skolan kan även bero på andra faktorer som elever påverkas av utanför skoltid.</p><p>Studien syftar till att kartlägga olika faktorer som elever i årskurs 7-9 upplever som stressande och hur de tror att stressen kan reduceras. Detta arbete har utgått från en frågeställning som framförts av en skola. En enkät användes för att kartlägga olika stressfaktorer. Intervjuer gav djupare förståelse för de olika stressfaktorerna och hur eleverna tror att den upplevda stressen kan reduceras. Det insamlade materialet tolkades i flera steg med ad hoc-metoder.</p><p>Resultatet visar att hälften av eleverna känner sig stressade varje vecka. Elevernas största stressfaktorer är tidsbrist och krav. De saknar ”fri tid”, som ger kroppen återhämtning från stress. Eleverna efterlyser ledarskap, hjälp från föräldrar att prioritera och sätta gränser samt att skolan ska utveckla elevernas studietekniker. Stressen orsakas av en känsla att inte kunna leva upp till och hantera egna och omvärldens krav. Reducering av stressen kan ske genom planering (skapande av ”fri tid”), inflytande (samplanering), personlig utveckling (stärkt självkänsla och identitet) och ledarskap (ledning, gränssättning, acceptans och utveckling).</p>
90

The relationship between caregiving and bereavement: A series of three studies

Burton, Allison 01 June 2005 (has links)
Spousal bereavement has been consistently demonstrated in the literature to be one of the most highly stressful experiences in an individuals lifetime. In addition many deaths in the United States are preceded by a period of caregiving, which is also believed to be highly stressful and have a profound impact on bereavement. However the literature has been inconsistent as to the exact nature of the relationship between caregiving and bereavement and there has been some debate as to whether or not positive and negative affect variables are mutually exclusive. This dissertation sought to further address the issue of the relationship between caregiving and the bereavement experience through a series of three studies which utilized information from two datasets. The first was the Changing Lives of Older Couples (CLOC) study, a project that included both pre- and post-loss data. The second was a subset of a dataset that recruited elderly spousal caregivers of terminally ill patients from a large, local non-profit hospice. This dataset included both pre- and post-loss data and included a variety of widely used and validated measures that allowed for the examination of caregiving stressors, appraisals, and social support and their effect on both positive and negative mental health outcomes during bereavement.The first study examined the impact of caregiving on well-being during bereavement, specifically within the domains of psychological, social, and physical health, utilizing both positive and negative affect measures.

Page generated in 0.0619 seconds