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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.
561

Avaliação ecotoxicológica de sedimentos em reservatórios da bacia do rio Tietê, SP, com ênfase na aplicação do estudo de AIT - Avaliação e Identificação da Toxicidade / Ecotoxicological evaluation of sediments in reservoirs of the Tietê river basin SP, with emphasis on the application of the TIE approach - Toxicity Identification and Evaluation

Clarice Maria Rispoli Botta Paschoal 30 September 2002 (has links)
A avaliação ecotoxicológica dos sedimentos dos reservatórios de Barra Bonita e Salto Grande foi realizada através de testes de toxicidade aguda e crônica com o sedimento total e o solubilizado, com os organismos-teste Chironomus xanthus, Daphnia similis, Ceriodaphnia dubia, Vibrio fisheri e Spirillum volutans, além de análises físicas (pH, EH e \'O IND.2\') e químicas (fósforo, nitrogênio, carbono orgânico total, sulfetos e amônia e metais potencialmente disponíveis). A concentrações médias de matéria orgânica e fósforo obtidas para os sedimentos dos reservatórios de Barra Bonita e Salto Grande foram elevadas, e condizentes com a carga de matéria orgânica e com as baixas concentrações de oxigênio dissolvido e de potencial redox. Em relação aos metais, os resultados revelaram que, para o reservatório de Barra Bonita, eles podem estar influenciando a toxicidade detectada através dos testes de toxicidade. Em Salto Grande, os resultados indicaram que os sulfetos estão atuando como fase controladora dos metais, mantendo-os indisponíveis nos sedimentos. Para esse reservatório a principal causa da toxicidade foi a acidez. O estudo de Avaliação e Identificação da Toxicidade realizado com as amostras de sedimento dos reservatórios de Barra Bonita, Salto Grande e Rasgão mostrou que os possíveis compostos tóxicos responsáveis pela toxicidade são metais (Barra Bonita); amônia (Salto Grande e Rasgão); compostos ácidos voláteis e compostos orgânicos não iônicos (Rasgão). O tratamento com a resina zeolita foi eficiente na remoção da amônia e redução da toxicidade do sedimento do reservatório de Rasgão, confirmando dessa forma, a amônia como o principal composto tóxico. O estudo de Avaliação e Identificação da Toxicidade deve ser incorporado nos programas de controle, monitoramento e gestão dos recursos hídricos, devido a importância da identificação dos compostos responsáveis pela toxicidade. / An ecotoxicological evaluation of the sediments of Barra Bonita and Salto Grande reservoirs was performed by carrying out acute and chronic toxicity tests with both the total sediment and elutriate using Chironomus xanthus, Daphnia similis, Ceriodaphnia dubia, Vibrio fisheri and Spirillum volutans as test-organisms, as well as physical (pH, EH e \'O IND.2\') and chemical analysis (phosphorus, nitrogen, total organic carbon, sulphide, ammonium and potentially available metals). The mean concentrations of organic matter and phosphorus obtained for the sediments of Barra Bonita and Salto Grande reservoirs were high and in agreement with the organic matter loading, low dissolved oxygen concentrations and redox potential. In relation to metals, the results revealed that in Barra Bonita reservoir they might be responsible for the toxicity detected. For Salto Grande, the results indicated that sulphides act as metal controlling phase keeping them unavailable in the sediments. The main cause of the toxicity in this reservoir was acidity. The Toxicity Identification and Evaluation (TIE) carried out with the sediments of Barra Bonita, Salto Grande and Rasgão have shown that the probable toxic compounds responsible for toxicity are metals (Barra Bonita); ammonium (Salto Grande and Rasgão); volatile acid compounds and non-ionic compounds (Rasgão). The treatment with zeolite was efficient in removing ammonium and reducing toxicity in the sediment of Rasgão reservoir, thus confirming ammonium as the main toxic compound. The Toxicity Identification and Evaluation approach must be incorporated in the control, monitoring and management of water resources, due to the relevance of identifying the compounds responsible by the toxicity.
562

Assessment of embryotoxicity of the antiandrogenic drugs flutamide and bicalutamide in zebrafish (Danio rerio)

Holmlund, Josefin January 2020 (has links)
Introduction: Prostate cancer is the most common type of cancer in Sweden and is often treated using antiandrogenic drug therapy. Two substances belonging to this class of pharmaceuticals are bicalutamide and flutamide. After excretion from the human body, the drug molecules enter the wastewater treatment plant (WWTP). The WWTPs are not effective enough to completely remove pharmaceutical residues, why presence of both bicalutamide and flutamide can be detected in WWTP effluent water. Previous findings: Antiandrogens have been reported to affect reproduction in adult fish, but studies regarding possible effects on the embryonic development of fish are few. Aim: The present study sought to investigate if exposure to bicalutamide or flutamide cause toxicity in the early developmental stages of zebrafish embryos, and whether negative effects occur within concentrations relevant to measured environmental levels. Method: A modified OECD FET-test was used, where additional sublethal endpoints were included and the time period for assessment extended to 144 hours post fertilization (hpf). In addition, a locomotor activity assay was performed at 144 hpf in order to observe any sub-lethal swimming behavioral effects. Results: High doses (10 mg/L) of flutamide led to 100% lethality of the zebrafish embryos but the results suggest no acute toxic effects in the high dose treatment group of bicalutamide, or of either flutamide or bicalutamide within in the low (0.1 mg/L) or intermediate (1 mg/L) treatment groups. Neither did the locomotor activity assay result in statistically significant results, although the pattern of swimming activity in the low dose groups suggests that behavioral developmental effects could be present. Conclusions: High doses of flutamide caused mortality of the embryos, but no lethal or sublethal effects were present at environmentally relevant concentrations. The modest outcome of present study however suggests that further investigation of behavioral developmental effects of antiandrogens could be of future relevance. Analysis of the expression of genes related to neuronal growth, memory and other cognitive behaviors associated with behavioral changes, would then be of interest for further studies.
563

The Effects of Neonicotinoid Exposure on Embryonic Development and Organ Mass in Northern Bobwhite Quail

Gobeli, Amanda 05 1900 (has links)
Since their emergence in the early 1990s, neonicotinoid use has increased exponentially to make them the world's most prevalent insecticides. Although there is considerable research concerning the lethality of neonicotinoids, their sub-lethal and developmental effects are still being explored, especially with regards to non-mammalian species. The goal of this research was to investigate the effects of the neonicotinoid imidacloprid on the morphological and physiological development of northern bobwhite quail (Colinus virginianus). Bobwhite eggs (n = 650) were injected with imidacloprid concentrations of 0 (sham), 10, 50, 100 and 150 grams per kilogram of egg mass, which was administered at day 0 (pre-incubation), 3, 6, 9, or 12 of growth. Embryos were dissected on day 19 when they were weighed, staged, and examined for any overt structural deformities. Embryonic heart, liver, lungs and kidneys were also weighed and preserved for future use. Treated embryos exhibited increased frequency of severely deformed beaks and legs, as well as larger hearts and smaller lungs at the higher dosing concentrations. Some impacts are more pronounced in specific dosing periods, implying that there may be critical windows of development when embryos are highly susceptible to neonicotinoid exposure. This investigation suggests that imidacloprid could play a significant role in chick survival and declining quail populations in treated regions of the country.
564

Eco-design of Emerging Photovoltaic (PV) Cells

Celik, Ilke January 2018 (has links)
No description available.
565

Prädiktive Wertigkeit dreier onkogeriatrischer Screenings: G8, optimierter G8 sowie CARG (Hurria) Score bezüglich der Vorhersage schwerer Chemotherapie assoziierter Toxizität bei älteren Krebspatienten

Kotzerke, David Immanuel 05 March 2021 (has links)
Background: Older patients are vulnerable to chemotherapy-related toxicity (CRT). Therefore we evaluated screening tools in their power to predict CRT. Methods: Patients with cancer aged ≥65 years completed three screening questionnaires (G8, optimised G8 and Cancer and Ageing Research Group (CARG). Additionally, Comprehensive geriatric assessment (CGA) for verification of supportive care needs was undertaken on patients with impaired G8 scores. During chemotherapy treatment patients were assessed, capturing grade 0–5 CRT as defined by NCI CTCAE 4. Results: 104 patients with non-haematological cancers were included at three study sites. Median age was 73 years (range 65–85). Onco-geriatric screening detected 74% as impaired using G8 and optimised G8 questionnaires and 86% using CARG screening. Grade 3–5 toxicity affected 64.4% of all patients. G8 (OR 0.3 95% CI [0.1;1.0]) and optimised G8 (OR 0.4 95% CI [0.1; 1.5]) did not reliably predict CRT, whereas screening with CARG demonstrated a strong prediction of severe CRT: OR 4.2, 95% CI [1.1, 15.9]. CGA was undertaken on 66 patients, revealing deficiencies in nutritional (83%) and functional-status (54%) and occurrence of relevant comorbidity (53%). Conclusion: The CARG tool could be useful for predicting CRT. CGA showed clinically relevant supportive care needs in patients with a positive G8 screening.:1. Einleitung ..................................................................................................................................... - 3 - 1.1 Epidemiologie der Krebserkrankungen bei älteren Patienten .................................................. - 4 - 1.2 Herausforderungen der geriatrischen Onkologie ..................................................................... - 5 - 1.3 Status Quo ................................................................................................................................. - 7 - 1.4 Geriatrisches Assessment (GA)................................................................................................ - 11 - 1.6 Geriatrisches Screening ........................................................................................................... - 13 - 1.5 Chemotherapie assoziierte Toxizität ....................................................................................... - 15 - 2 Ableitung der Studienrationale ...................................................................................................... - 17 - 3 Publikationsmanuskript .................................................................................................................. - 18 - 4 Zusammenfassung der Arbeit ........................................................................................................ - 26 - 5 Literaturverzeichnis der Einleitung ................................................................................................ - 29 - 6 Anlagen ........................................................................................................................................... - 35 - 7 Abkürzungsverzeichnis ................................................................................................................... - 52 - 8 Erklärung über die eigenständige Abfassung der Arbeit ................................................................ - 53 - 9 Lebenslauf – David Immanuel Kotzerke ......................................................................................... - 54 - 10 Spezifizierung des eigenen Beitrages ........................................................................................... - 56 - 11 Danksagungen .............................................................................................................................. - 58 -
566

The role of retinoic acid receptor gamma in retinoid-induced limb dysmorphogenesis /

Galdones, Eugene. January 2009 (has links)
No description available.
567

Toxicity Levels of Stock Markets : Observing Information Asymmetry in a Multi-Market Setting / Aktiemarknaders Toxicity-Nivaer : Observering av Informationsasymmetri i en Flermarknadsmiljo

Molander, Lukas, Yape, Shih Jung January 2017 (has links)
The presence of toxic order ow and predatory HFT strategies in a multi-market setting are scarcely researched in the academic world. This thesis studies the toxicity levels of a set of markets by examining unconsolidated quote data and firm specific trade data. A method for deducing the markets toxicity levels is presented along with proxies for toxic order ow, namely: changes in spread and quoted volume, following a trade in a given market. We find both signs of toxicity and different toxicity levels between the markets. However, the results are lacking in statistical significance but they show that this field is of great interest for further research. Also, the methods proposed for deducing the toxicity levels are rudimentary but could serve well as a premise for further development. / Närvaron av toxic order flow och predatoriska HFT-strategier i en flermarknadsmiljö är föga studerat i den akademiska världen. Denna avhandling studerar detta på en uppsättning marknader genom att undersöka okonsoliderad quote data och firma specifika trades, och på så vis ta fram marknadernas toxicity-nivåer. En metod för att fastställa marknadernas toxicity-nivåer presenteras tillsammans med proxys för toxic order flow, mer specifikt: förändringar i spread och quotad volym, efter en handel på en given marknad. Vi finner både tecken på toxicity och olika toxicityniv åer mellan marknaderna. Resultaten saknar dock statistisk signifikans men de visar ändå på att detta område är av stort intresse för ytterligare forskning. De metoder som föreslås för att fastställa toxicity-nivåerna är rudimentära, men kan tjäna som en utgångspunkt för vidare utveckling.
568

Developmental Toxicity Assessment of Perfluoroalkyl Substances (PFAS) Using Zebrafish Model System

Ola Wasel (13158639) 27 July 2022 (has links)
<p>  </p> <p>Perfluoroalkyl substances (PFAS) are synthetic chemicals that are composed of fluorinated aliphatic chains and are widely used in industrial and consumer products. These chemicals are very stable and persist in the environment. Due to concerns linked with longer chain PFAS, shorter chain chemicals are being used as replacements. There are limited human health data regarding the shorter chain chemicals. In addition, these alternatives are persistent in the environment similar to the longer chain PFAS. The main objective of this dissertation was to assess developmental toxicity of the shorter chain PFAS or shorter chain PFAS with chemical modifications represented by perfluorobutanoic acid (PFBA, C4), perfluorohexanoic acid (PFHxA, C6), perfluorobutane sulfonate (PFBS, C4), and perfluoro-2-proxypropanoic acid (GenX, C6). Overall, the results showed that chain length and functional group are determinants of toxicity of PFAS. All tested PFAS induced one or more developmental adverse outcome, but the effects of each chemical are unique, warranting further studies to address the toxicity of the replacement PFAS. </p>
569

Tegdma induction of apoptotic proteins in pulp fibroblasts

Batarseh, Ghada January 2011 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Monomers like triethylene glycol dimethacrylate (TEGDMA) leach from dental composites and adhesives due to incomplete polymerization or polymer degradation. The release of these monomers causes a variety of reactions that can lead to cell death. This death can be either necrotic, which is characterized mainly by inflammation and injury to the surrounding tissues, or apoptotic, which elicits little inflammatory responses, if any at all. TEGDMA-induced apoptosis in human pulp has been reported recently. However, the molecular mechanisms and the apoptotic (pro and anti) proteins involved in this process remain unclear. The objective of this study was to determine the apoptotic proteins expressed or suppressed during TEGDMA-induced apoptosis. Human pulp fibroblasts (HPFs) were incubated for 24 hours with different TEGDMA concentrations (0.125-1.0 mM). Cytotoxicity was determined using the cytotoxicity Detection KitPLUS (Roche Applied Science, Mannheim, Germany). TEGDMA was shown to cause cell cytotoxicity at concentrations of 0.50 mM and up. The highest concentration with no significant cytotoxicity was used. Cells were incubated with or without 0.25 mM TEGDMA for 6 h and 24 h. Cell lysates were then prepared and the protein concentrations determined using the Bradford protein assay. A Human Apoptosis Array kit (Bio-Rad Hercules, CA ) was utilized to detect the relative levels of 43 apoptotic proteins. The results of this study showed statistically significant increases of multiple examined pro-apoptotic proteins. The anti-apoptotic proteins were also altered. Pro-apoptotic proteins involved in the intrinsic and extrinsic apoptotic pathways were increased significantly. The results indicated that TEGDMA has effects on both the extrinsic and intrinsic apoptotic pathways.
570

Profesinės ligos Lietuvoje 1973-1978 m / Occupational diseases in lithuania during the period of 1973-1978

Šiukštaitė, Ieva 27 June 2014 (has links)
Darbo tikslas Aprašyti profesinių ligų tendencijas Lietuvoje 1973-1978 m. Uždaviniai 1. Nustatyti profesinių ligų skaičiaus ir sergamumo rodiklio pokyčius 1973-1978 m. Lietuvoje. 2. Nustatyti profesinių ligų pasiskirstymą Lietuvoje 1973-1978 m. pagal rizikos veiksnius, ligų grupes, ekonominės veiklos rūšis bei apskritis. 3. Nustatyti profesinių ligų pasiskirstymą Lietuvoje 1973-1978 m. pagal lytį ir darbo stažą. Metodika Duomenys apie 1303 profesinių ligų atvejus buvo surinkti iš 6 LCVA bylų, kuriose yra surinktos 1973-1978 m. tuometinės LTSR SAM ketvirtinės profesinių ligų ataskaitos bei teritorinių SES pranešimai apie profesines ligas. Aprašomoji statistika atlikta Microsoft Excel 2003, Microsoft Excel 2003, WinPepi 11.18, SPSS 17.0 programomis, naudojant &#967;2 ir tikslųjį Fišerio kriterijų. Išvados apie santykinio požymių skirtumo statistinį reikšmingumą buvo daromos, kai p &#8804; 0,05. Rezultatai ir išvados Vidutinis sergamumo profesinėmis ligomis Lietuvoje 1973-1978 m. rodiklis buvo 16,3 / 100 tūkst. dirbančiųjų. Daugiausiai profesinių ligų buvo įtakotos fizikinių veiksnių (51,04 proc.). Daugiausiai registruota ausies (35,5 proc.) ir jungiamojo audinio ir skeleto raumenų sistemos (17,2 proc.) ligų. Daugiausiai profesinių ligų registruota Kauno (31,2 proc.) apskrityje bei apdirbamosios gamybos darbuotojams (64,1 proc.). Vyrams daugiau buvo registruota ūmių profesinių ligų, o moterims – lėtinių. Moterys daugiau sirgo ausies bei nervų sistemos ligomis, o vyrai jungiamojo... [toliau žr. visą tekstą] / Purpose of Study Describe tendencies of occupational diseases in Lithuania in 1973-1978. Objectives 1. Set the number of occupational diseases and the incidence rate of change in Lithuania in 1973-1978. 2. Determine the distribution of occupational diseases according to risk factors, disease groups, industry and region in Lithuania in 1973-1978. 3. Determine the distribution of occupational diseases by sex and total experience of working in Lithuania in 1973-1978. Methodology Data on occupational diseases about 1303 cases were collected from LCVA of 6 files, in which Lithuanian SSR Ministry of Health quarterly reports and territorial Sanitary Epidemiological Station reports about occupational diseases are archived. Descriptive statistics performed in Microsoft Excel 2003, Microsoft Excel 2007, WinPepi 11.18, SPSS 17.0 programs using &#967;2 and Fisher's exact test. Conclusions about the relative signs of the difference between statistical significance were made at p &#8804; 0.05. Conclusions and Results The average incidence rate of occupational diseases in Lithuania in 1973-1978 was 16.3 / 100 000 workers. Most occupational diseases have been influenced by physical factors (51.04%). Majority of them was ear (35.5%) and connective tissue and musculoskeletal system (17.2%) diseases. Most occupational diseases registered in Kaunas (31.2%) and for manufacturing workers (64.1%). There have been registered more acute occupational disease for men, and chronic for women. Women had... [to full text]

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