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  • 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.
21

Using High Frequency Monitoring of Environmental Factors to Predict Cyanotoxin Concentrations in a Multi-use, Inland Reservoir

Varner, Mia 28 September 2018 (has links)
No description available.
22

The Role of Microzooplankton and Mesozooplankton Grazing During the Planktothrix-Dominated Cyanobacterial Blooms in Sandusky Bay, Lake Erie

Kennedy, Matthew R. 12 August 2020 (has links)
No description available.
23

Shareholder reaction to corporate eco-harmful behaviour: a cross-country comparison between Germany and China

IJmker, Sander January 2016 (has links)
In this study, the difference between shareholder reactions to eco-harmful behaviour by firms in China and Germany are being researched. Previous research has focused on shareholder reaction in developed countries, especially the US. What remains unknown is whether shareholders in developing countries have adopted the same norms concerning the environment as shareholders in developed countries. Institutional theory, legitimacy theory and desensitization theory are examined in this study. An event study was conducted with an [-1,1] and [-1,3] event window surrounding the announcement of eco-harmful behaviour by firms. Events were drawn from relevant news articles and environmental databases. In total 43 events have been discovered over the years 2007 to 2015. Overall, results indicate that the decrease in share prices is not significantly different from zero. However, when comparing China and Germany, evidence is found that Chinese firms are punished more severely than German firms when corporations harm the environment. Contrary to expectations, it can be concluded that the institutionalization of environmental norms has taken place in China, either through internal or global pressures.
24

Primärvårdschefers uppfattning om arbetet med patienter med risk- och missbruksproblem

Magnusson, Katarina January 2012 (has links)
The Purpose of the study was to highlight the primary care managers' perception of the barriers and opportunities in the implementation of the national guidelines for harmful drinking and alcohol abuse in KalmarCounty. The data was collected by questionnaires which were directed to all primary care managers in the county. The response rate was low, 40%. The data collection was complemented at a later stage with a non-response analysis. To analyze the results implementation theory with following terms were used: wants to, understand and know. In this study, the managers response showed an ambivalence and the willingness to use the national guidelines were not evident. On the one hand, patients with for harmful drinking and alcohol abuse is a tasks for primary care, but on the other hand, it was considered to a greater extent to be social services responsibility. The understanding of the use of guidelines existed and primary care has a tradition of making use of the guidelines, however in this case the respondents lack education. The ability to implement the national guidelines seemed lacking, which may be due to increased tasks and radical changes involving time constraints.
25

Causes and Consequences of Algal Blooms in the Tidal Fresh James River

Wood, Joseph 25 April 2014 (has links)
This dissertation includes 3 chapters which focus on algal bloom of the tidal fresh James River. The first chapter describes nutrient and light limitation assays performed on algal cultures and draw conclusions about long-term patterns in nutrient limitation by comparing results with a previous study . This chapter also describes the influence of riverine discharge upon nutrient limitation in a point-source dominated estuary. This chapter was published in Estuaries and Coasts (Wood and Bukaveckas 2014). The second chapter presents the first comprehensive assessment of the occurrence of the cyanotoxin Microcystin in water and biota of the James River. Data presented in this chapter show that bivalve grazing declines in the presence of Microcystin in the water. The chapter also describes feeding habits in fish as a predictor for inter-specific differences in Microcystin accumulation in their tissues. The work presented in this chapter was published in Environmental Science & Technology (Wood et al. 2014). The third chapter describes the fate of algal carbon in the James River Estuary and the importance of autochthonous and allochthonous sources of organic matter in supporting production of higher trophic levels. Here I draw upon ecosystem metabolism data (NPP and R), abundance and grazing estimates for primary consumers and estimates of advective losses of chlorophyll and external inputs of nitrogen to place ‘top-down’ effects in the broader context of factors influencing chlorophyll and nitrogen fluxes in the James. . This chapter also describes results from mesocosm experiments used to assess the influences of grazers on chlorophyll, nutrients and Microcystis. This work will be submitted in the summer of 2014 to the journal Ecosystems.
26

Effects of the Algal Toxin Microcystin on Fishes in the James River, Virginia

Haase, Maxwell D 01 January 2015 (has links)
With the global rise in frequency of harmful algal blooms in estuarine environments comes an increase in prevalence of toxic metabolites, such as microcystin (MC), that some of the cyanobacteria involved will produce. At high concentrations, MC may accumulate in consumer tissues and have deleterious effects on organisms; however impacts of the toxin on aquatic living resources at ecologically relevant concentrations have not been widely documented. We analyzed the effects of MC on juveniles of five fish species from the James River, Virginia to determine if MC has the potential to impede growth. Using three separate experimental approaches, it was shown that exposure to concentrations of the toxin currently observed in the James River estuary do not appear to significantly impact the growth or survivorship of tested fish species. Extraneous factors in parts of the study led to an inability to draw clear conclusions on mortality or growth impacts; however it is evident from the experiments that at least some of the fish species have biological mechanisms in place that allow them to effectively eliminate the toxin from their systems. An ability to extricate the toxin suggests the possibility for fishes to withstand MC exposures and sustain few negative health impacts at low MC concentrations.
27

Vliv metanolové kauzy na vzorce užívání alkoholu v ČR: internetový průzkum / Effect of methanol affair on patterns of alcohol use in the Czech Republic: online survey

Přibylová, Eva January 2014 (has links)
In the fall of 2012 took place in the Czech Republic, the methanol case - were poisoned and subsequently to the death of many people. According Zakharov (2013, oral communication) is currently the actual number of victims as 58, with the death of the last of methanol poisoning occurred in early December 2013. Methanol was poisoned dozens of people, from those who survived methanol poisoning has many of them probably lifelong consequences - especially disturbances and disorders of the central nervous system. The main objective of this thesis is to describe what has or has Methanol cause effects on patterns of alcohol and behavior related to alcohol use among target groups and to compare any differences in terms of socio-demographic characteristics, the awareness about the issue of methanol and patterns of use (including use of a harmful dependence). For the realization of this investigation was chosen quantitative research. The theoretical part focuses on alcohol (pharmacodynamics, kinetics, effects of alcohol on the human body or patterns of use). I mention the alcohol addiction and treatment options. I also deal with methanol (kinetics, metabolism, toxicity and poisoning), and finally to the specific aspects of mass poisoning with methanol in the Czech Republic. Data were collected from 25 May to...
28

The experiences of parents of children who have engaged in harmful sexual behaviour : an interpretative phenomenological analysis

Archer, Elisabeth January 2017 (has links)
Background and Aims: The importance of the involvement of parents in treatment approaches for Children and Young People (CYP) who have engaged in Harmful Sexual Behaviour (HSB) has been consistently highlighted within the literature. Given that HSB arises in a family context, parents are considered key agents for change where CYP remain in their care. Professionals may work with them as a means of improving the CYP's therapeutic outcomes. Despite this, little is known about their personal lived experiences and representations of meaning, which remain largely unexplored. The current study aimed to address this gap and gain a rich understanding of the experiences of parents, from their own perspective. Methodology: Semi-structured interviews were used with six biological parents who were recruited via purposive sampling from a specialist service working with CYP who have engaged in HSB and their families. During interviews, four broad areas of interest were explored: the personal psychological impact of their child engaging in HSB; the impact on the parent-child relationship; wider familial and community responses; and parental coping. Interviews were audio-recorded and their verbatim transcripts analysed using Interpretative Phenomenological Analysis (IPA). Findings and Conclusions: The analysis produced four main themes; 'A devastated and overwhelmed life'; 'Threatened and trying to feel safer'; 'A challenged relationship with son'; and 'Space for hope in the face of hopelessness?'. It was highlighted that parents' experiences and meaning-making appeared intimately woven with a complex web of powerful relational and socially constructed factors. The research outcomes provide valuable insights for professionals working with young people who have engaged in HSB and their families. In learning more about what it is like to be the parent of a CYP who has engaged in HSB, it is hoped that professionals will have a richer framework from which to provide support to both the parent and to their child. Implications for clinical practice, the strengths and limitations of the methodology and directions for future research are discussed.
29

Dípteros frugívoros (Tephritidae e Lonchaeidae) na região de Mossoró/Assu, Estado do Rio Grande do Norte. / Frugivorous dipterans (tephritidae and lonchaeidae) in the Mossoró/Assu, state of Rio Grande do Norte.

Araujo, Elton Lucio de 08 March 2002 (has links)
A região de Mossoró/Assu (RN), localizada no semi-árido, destaca-se pela produção e exportação de frutas, principalmente o melão Cucumis melo e a manga Mangifera indica. Portanto, este trabalho teve como objetivo conhecerer vários aspectos relacionados as moscas-das-frutas (Dip.; Tephritidae) e aos lonqueídeos (Dip.; Lonchaeidae) nessa região. Após dois anos de coletas, em armadilhas McPhail e frutos, foram detectadas dez espécies de tefritídeos e uma única de lonqueídeo Neosilba pendula (Bezzi). As moscas-das-frutas mais comuns foram Anastrepha zenildae Zucchi, A. obliqua (Mcquart) e Ceratitis capitata (Wied.). As maiores infestações foram observadas em frutos de juá Ziziphus joazeiro (Rhamnaceae) e kunquat Fortunella sp. (Rutaceae). Em alguns meses do ano, A. zenildae foi considerada praga em pomares de goiaba Psidium guajava (Myrtaceae). A população de adultos, a disponibilidade do hospedeiro, a precipitação pluvial e a temperatura, foram os fatores que mais influenciaram os níveis de infestação das espécies de Anastrepha em frutos de goiaba. Neosilba pendula apresentou baixos níveis de infestação nas frutíferas da região, mas foi considerada um importante invasor primário de frutos de acerola Malpighia emarginata (Malpighiaceae). Três espécies de parasitóides (Braconidae) foram obtidos dos pupários das moscas-das-frutas, sendo Doryctobracon areolatus (Szépligeti) o mais comum. / The Mossoró/Assu region (RN), located in a semi-arid zone, is important as a center of fruit production and export, especially melons, Cucumis melo, and, mangoes, Mangifera indica. Thus, the objective of the present study was to investigate several aspects related to fruit flies (Dip.; Tephritidae) and lonchaeids (Dip.; Lonchaeidae) in this region. After two years of collection with McPhail traps and reared from fruits, ten tephritid species and a single lonchaeid species, Neosilba pendula (Bezzi), were detected. The most common fruit flies were Anastrepha zenildae Zucchi, A. obliqua (Mcquart), and Ceratitis capitata (Wied.). The highest infestation levels were observed on 'juá' fruits, Ziziphus joazeiro (Rhamnaceae) and on kumquats, Fortunella sp. (Rutaceae). In some months of the year, A. zenildae was considered as a pest in guava, Psidium guajava (Myrtaceae), orchards. Adult population, host availability, rainfall and temperature were the factors that most influenced the levels of guava fruit infestation by Anastrepha species. Neosilba pendula showed low infestation levels on fruit trees of region, but was considered as an important primary invader of "acerola", Malpighia emarginata (Malpighiaceae). Three parasitoid species (Braconidae) were obtained from fruit fly puparia, the most common being Doryctobracon areolatus (Szépligeti).
30

Diagnóstico da ocorrência de cupins xilófagos em árvores urbanas do bairro de Higienópolis, na cidade de São Paulo. / Diagnosis of the occurrence of xylophagous termites in urban trees of a neighborhood of São Paulo city, Brazil.

Amaral, Raquel Dias de Aguiar Moraes 28 February 2002 (has links)
O problema de cupins xilófagos observado nas edificações e prédios históricos, localizados na cidade de São Paulo, Brasil, não se limita apenas a estas estruturas, mas também às árvores que, além de serem atacadas, podem constituir-se de abrigo para estes insetos de hábito subterrâneo. O fato destes cupins apresentarem grande capacidade de dispersão, pode comprometer a sanidade biológica de outras árvores e também das edificações. Como no Brasil verifica-se a falta de critérios para diagnosticar corretamente a infestação nas árvores, este trabalho têm como objetivos, verificar a existência de uma correlação de alguns indicadores externos, com a ocorrência interna de cupins xilófagos em árvores urbanas, além de estimar a intensidade dessa infestação por meio de uma avaliação não-destrutiva. Foram diagnosticadas 49 árvores por meio da análise externa da presença de vestígios ou túneis de cupins na casca e entre casca e no solo junto à base da árvore, das condições gerais e do local em que a árvore encontrava-se plantada. Além da análise externa, também foi realizada a prospecção interna do tronco com a utilização de um método não-destrutivo para verificar a intensidade do possível ataque causado pelos cupins xilófagos.Dos indivíduos inspecionados, 28,60% apresentaram cupins vivos ou sinais destes insetos e a espécie encontrada foi Coptotermes havilandi Holmgren. Também foi observada a existência de uma correlação entre um dos indicadores da análise externa com a análise interna em 50% dos casos. Quando observado o indicador análise externa do tronco, nos graus de intensidade "ataque" e "ataque intenso", a perda de resistência da madeira, na classificação "decaimento intenso", representava que a sanidade biológica interna, havia sido comprometida pela ação dos cupins. / The problem of xylophagous termites in the edifications and historical buildings of the city of São Paulo, Brazil, is not confined to these structures, but also to the trees which, besides being attacked can shelter these insects of subterranean habit. The dispersion capacity of these termites can jeopardize the biological sanity of other trees and also of buildings. As in Brazil there is a lack of criteria to correctly detect and verify termite infestation in trees, this work aims at determining the existence of a correlation between external indicators and the internal presence of xylophagous termites in urban trees, in addition to estimating the intensity of the termite infestation by means of non-destructive evaluation. Forty-nine trees were examined for external signs of the presence of termites, tunnels or vestiges in the bark or inner bark of the trees, in the soil around the base of the trees, the general conditions and the site where the trees were planted. In addition to the external analysis, an internal search in the trunk was carried out through a non-destructive method to estimate the intensity of the possible attack by termites.Of the trees inspected, 28,60% presented live termites or signs that indicated their presence, and the species found was Coptotermes havilandi Holmgren. An existing correlation between one indicator of the external analysis and the internal analysis was detected in 50% of the cases. When the indicator at external analysis of the trunk with the intensity degrees "attack" and "intense attack" was detected, the "intense decline" loss on wood strength meant that interns of internal biological sanity, the tree had been affected by termite action.

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