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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.
751

Sistemática de ações de segurança e saúde no trabalho para laboratórios de pesquisa com atividades de nanotecnologia

Andrade, Luis Renato Balbão January 2013 (has links)
As nanotecnologias são um conjunto multidisciplinar de técnicas que manipulam a matéria em escala nanométrica, mais precisamente partículas abaixo de 100 nanômetros, cujas características por conta do tamanho diminuto são essencialmente diferentes daquelas encontradas no material em sua forma macro. Em função destas novas propriedades dos materiais, existem lacunas de conhecimento relativas aos efeitos destas partículas sobre o organismo humano e sobre o meio ambiente. Embora ainda sejam consideradas tecnologias emergentes, seu crescimento é cada vez mais acelerado e o número de produtos que fazem uso de nanotecnologia em alguma fase de sua produção continua crescendo, bem como o número de pesquisadores envolvidos com o tema. Considerando este cenário e a literatura pertinente, este trabalho objetivou desenvolver uma sistemática de ações de segurança e saúde no trabalho (SST) para laboratórios de pesquisa com atividades de nanotecnologia. Esta sistemática é fundamentada na estrutura das diretrizes para um sistema de gestão de segurança e saúde no trabalho proposto pela Organização Internacional do Trabalho (OIT). A esta base foram agregadas diversas recomendações nanoespecíficas, sendo desta maneira consolidada a Sistemática de SST para Laboratórios com Nanotecnologia (S-SST/LabNano). Além da comparação desta sistemática com outras apresentadas por outros autores, uma pesquisa survey foi realizada, com o propósito de obter um retrato da SST em laboratórios com atividades de nanotecnologia no Brasil. De forma complementar, objetivando a adequação prática, a S-SST/LabNano foi avaliada em relação a realidade de SST encontrada em laboratório. O resultado final da tese, além da sistemática em si (S-SST/LabNano), almeja oferecer elementos de reflexão que possam auxiliar a gestão e o controle de riscos ocupacionais associados às nanotecnologias. / Nanotechnology is a multidisciplinary set of techniques that manipulates material at nanoscale, precisely particles below 100 nanometers whose characteristics, due to the small size, are essentially different from those found in material while in macro format. In the light of these new properties of materials, there are knowledge gaps regarding the effects of these particles on the human body and the environment. Although still considered emerging technologies, their growth is increasingly accelerated and the number of products that use nanotechnology in some stage of its production continues to grow, as well as the number of researchers involved with the topic. Given this scenario and its relevant literature, this study aimed to develop a proposed methodology of actions in occupational safety and health (OSH) to research laboratories with nanotechnology activities. This methodology is based on the structure of the International Labour Organization (ILO) guidelines for a management system in safety and health at work. Several specific recommendations were added, named Participatory Nano Safety Lab (PNSL). Besides the confrontation of this proposal with other authors, a research survey was conducted with the purpose to obtain a general picture of the OSH in laboratories with nanotechnology activities in Brazil. In a complementary way, aiming a practical suitability, the PNSL was confronted with the reality of OSH found in laboratory. The final result of this thesis, besides the methodology itself (PNSL), aims to provide elements of reflection that may assist management and occupational risk control associated to nanotechnology.
752

Evaluation of subjective fatigue associated with chronic obstructive pulmonary disease

Lewko, Agnieszka January 2013 (has links)
No description available.
753

Transcriptome Analysis Of Lymphoma Associated Viruses And Analysis Of Viral Noncoding Rnas

January 2014 (has links)
No description available.
754

The Effect of Nine Diet and Water Combinations on the Culture Health of Ceriodaphnia Dubia

Patterson, Paul W. (Paul William) 05 1900 (has links)
Culture health of Ceriodaphnia dubia was evaluated for organisms cultured using all combinations of three foods and three waters. Criteria used to assess health of cultures included adult and neonate weights, time required to produce first broods, neonate production, adult survival, and resistance to hexavalent chromium. Diet/water combinations which produced the most neonates were not found to produce adults which were more resistant to chromium than those which produced fewer neonates. Of those evaluated, a diet of Selenastrum capricornutum and a yeast-trout chow-cereal leaf mixture was best for culturing and testing Ceriodaphnia. The best synthetic water tested was a mixture of nine parts reconstituted hard water and one part bottled mineral water.
755

Investigating Lava Flow Emplacement: Implications for Volcanic Hazards and Planetary Evolution

January 2020 (has links)
abstract: Lava flow emplacement in the laboratory and on the surface of Mars was investigated. In the laboratory, the effects of unsteady effusion rates at the vent on four modes of emplacement common to lava flow propagation: resurfacing, marginal breakouts, inflation, and lava tubes was addressed. A total of 222 experiments were conducted using a programmable pump to inject dyed PEG wax into a chilled bath (~ 0° C) in tanks with a roughened base at slopes of 0, 7, 16, and 29°. The experiments were divided into four conditions, which featured increasing or decreasing eruption rates for either 10 or 50 s. The primary controls on modes of emplacement were crust formation, variability in the eruption rate, and duration of the pulsatory flow rate. Resurfacing – although a relatively minor process – is inhibited by an extensive, coherent crust. Inflation requires a competent, flexible crust. Tube formation requires a crust and intermediate to low effusion rates. On Mars, laboratory analogue experiments combined with models that use flow dimensions to estimate emplacement conditions and using high resolution image data and digital terrain models (e.g. THEMIS IR, CTX, HRSC), the eruption rates, viscosities, and yield strengths of 40 lava flows in the Tharsis Volcanic Province have been quantified. These lava flows have lengths, mean widths, and mean thicknesses of 15 – 314 km, 0.5 – 29 km, and 11 – 91 m, respectively. Flow volumes range from ~1 – 430 km3. Based on laboratory experiments, the 40 observed lava flows were erupted at 0.2 – 6.5x103 m3/s, while the Graetz number and Jeffrey’s equation when applied to 34 of 40 lava flows indicates eruption rates and viscosities of 300 – ~3.5 x 104 m3/s and ~105 – 108 Pa s, respectively. Another model which accounts for mass loss to levee formation was applied to a subset of flows, n = 13, and suggests eruption rates and viscosities of ~30 – ~1.2 x 103 m3/s and 4.5 x 106 – ~3 x 107 Pa s, respectively. Emplacement times range from days to centuries indicating the necessity for long-term subsurface conduits capable of delivering enormous volumes of lava to the surface. / Dissertation/Thesis / Chapter 4 - Mars Lava Flow Data and Calculations / Chapter 2 - Experimental Data / Chapter 3 - Experimental Data / Doctoral Dissertation Geological Sciences 2020
756

Enabling Multi-Site, Tailored Feedback Interventions to Reduce Low-Value Test Ordering: A Systematic Approach

Podolsky, Eyal 28 October 2021 (has links)
Introduction: Innovations in modern medicine have led to the development of many effective laboratory tests for diagnosis and monitoring of disease. However, research suggests that 20-50% of tests may be inappropriately ordered. Test-ordering intervention development experts i.e. those staff at individual institutions who are tasked with designing different approaches to improving test-ordering practice, often have large datasets on the test-ordering practices within their jurisdiction as part of clinical care, but often have no clear guidance on how to choose which tests are worthy of intervention. These staff can include both clinicians and knowledge translation experts working in separately or in tandem to improve test-ordering behaviours at their institutions. The overall aim of this research is to build a prioritization framework to assist healthcare organizations in deciding which tests are worth targeting for intervention. Methods: The first stage of this project was a scoping review of the literature, the purpose of which was to determine the factors and processes used by intervention developers to choose which tests to target for intervention. Identification of these articles allowed for the descriptive analysis of the factors and processes reported in making the test-ordering decisions. The second stage involved semi-structured interviews with intervention development experts and contains information on their experiences with measuring and prioritizing among factors, as well as which processes they found to be most effective in making the decision on which tests to target for intervention. Results: By exploring all relevant guideline statements and related empirical studies, we gathered a wide range of factors to consider when deciding which test(s) to target for intervention. Overall, we identified 18 factors in our review and 30 in our interviews, highlighting the potential complexity of these decisions. While our studies were not the first to demonstrate that targeting tests is complex and that many factors must go into the decision of deciding which tests to target, our work has identified the most comprehensive range of factors available. We also explored processes reported by the studies that led to these decisions. Of the nine processes identified in our review, some were identified in a majority of cases (literature review, followed by clinical standard-implicit and consensus process), and other processes far more infrequently. Our interviews with relevant stakeholders demonstrated that the interviewees used 18 unique processes to decide which tests to target for intervention and helped to prioritize among the processes that are most effective in making these decisions. Conclusion: The current work prepares the way to develop a framework designed to help intervention developers choose which tests can most efficiently result in improved test-ordering processes. After additional interviews to ensure saturation of themes, we will be able to proceed with framework development, perhaps involving a consensus process of all relevant stakeholders. We hope to widely distribute our framework to assist intervention development experts working in a wide variety of milieus to help them decide which tests are worth targeting for intervention such that their respective institutions can provide the highest quality of care to patients.
757

Student Perceptions of the Online Introductory Biology Laboratory Curriculum Using a Framework of Vision and Change and its Core Competencies

Ulrich, Erin R. 11 May 2021 (has links)
No description available.
758

Effects of Food Consumption on Cell Proliferation in the Brain of Python regius

Habroun, Stacy Star 01 June 2017 (has links)
Neurogenesis is an important and vastly under-explored area in reptiles. While the ability to generate new brain cells in the adult mammalian brain is limited, reptiles are able to regenerate large populations of neuronal cells. Pythons exhibit a characteristic specific dynamic action (SDA) response after food intake with an increase in metabolic rate that facilitates processing the meal. Associated with this change in SDA, pythons (Python spp.) also exhibit impressive plasticity in their digestive and cardiovascular physiology due to the sheer magnitude of the increase in organ growth that occurs after a meal to speed digestion, absorption, and assimilation of nutrients. While this systemic growth in response following food consumption is well documented, whether the python brain exhibits associated changes in cell proliferation following food consumption and digestion is currently unexplored. For this study, juvenile male ball pythons (Python regius) were used to test the hypothesis that postprandial neurogenesis is associated with food consumption. We used the thymidine analog 5-bromo-12’-deoxyuridine (BrdU) to quantify and compare cell proliferation in the brain of fasted snakes and at two time points: two days and six days after a meal, which span time periods of during and after SDA response, respectively. Quantification of BrdU-labeled cells in the ventricular regions relealed that – consistent with other reptile species – the retrobulbar and olfactory regions had the highest numbers of proliferating cells in the python brain, regardless of sampling time. Throughout the telencephalon, cell proliferation was significantly greater in the six-day post-feeding group, with no difference between the two-day post-feeding group and controls. Most other postprandial systemic plasticity occurs within a day or two after a meal and decreases thereafter; however, the brain displays a more delayed response, with a surge of cell proliferation after most of the digestion and absorption is complete. Our results support our hypothesis that food consumption does affect cell proliferation in the python brain, and indicates that the degree of increased proliferation is dependent on the time since feeding.
759

Principy generování RF signálů - laboratorní přípravek / Generation of RF signals - educational laboratory examples

Uhliar, Marek January 2020 (has links)
The work deals with design, simulation and preparation of laboratory preparation. The main aim of the thesis is to design and implement a simple noise generator, signal sources, mixer and phase lock loop for teaching purposes.
760

Laboratory Simulation and Evaluation of Aerosol Particles Penetration, Deposition and Removal Processes in Sheltering Houses Equipped with Ventilation Systems / 換気システムを備えた待避家屋におけるエアロゾル粒子の侵入、沈積および除去プロセスの実験室シミュレ-ションと評価

Wenlu, Wang 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22764号 / 工博第4763号 / 新制||工||1745(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 米田 稔, 教授 橋本 訓, 准教授 福谷 哲 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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