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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.
1

Statistical methodology and causal inference in studies of the health effects of radiation

Stone, R. A. January 1986 (has links)
No description available.
2

Estudo da radiolise do acido succinico-aplicacao em dosimetria de altas doses

ANDRADE e SILVA, LEONARDO G. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:18Z (GMT). No. of bitstreams: 1 00028.pdf: 1090739 bytes, checksum: 45730157ed376e986bf6b19dfd1170f2 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
3

Estudo da radiolise do acido succinico-aplicacao em dosimetria de altas doses

ANDRADE e SILVA, LEONARDO G. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:18Z (GMT). No. of bitstreams: 1 00028.pdf: 1090739 bytes, checksum: 45730157ed376e986bf6b19dfd1170f2 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
4

Vancomycin Loading Doses in Septic Patients

He, Junyan, Mee, George, Bingaman, Marc, Patanwala, Asad January 2015 (has links)
Class of 2015 Abstract / Objectives: To (1) characterize loading doses of vancomycin administered to patients with sepsis and (2) evaluate the relative impact of loading dose on clinical outcomes between patients who received a 1 gram loading dose or any other amount. Methods: Retrospective, observational chart review of adult patients who received vancomycin for treatment of sepsis through emergency department triage. Data from November 2013 through March 2014 were obtained for timing and administration of vancomycin as well as clinical outcomes: survival; length of hospitalization and intensive care unit (ICU) stay; need for mechanical ventilation. Results: Sepsis-related hospital encounters were identified for 123 patients, of which 114 charts were fully able to be evaluated. The majority of patients (84.21%) received a 1 gram loading dose as opposed to any other amount (p=0.001); few patients (1.75%) received a dose within 25-30 mg/kg. No significant differences in trends for timing of administration, inpatient survival, duration of hospital stay, or need for mechanical ventilation were identified between patients who received 1 gram doses or any other amount. Greater effective vancomycin loading doses were associated, albeit not significantly, with shorter durations of hospitalization, ICU admissions, and mechanical ventilation. Conclusions: Despite weight-based loading dose recommendations, vancomycin was frequently administered as a fixed 1 gram loading dose to patients with sepsis. However, there was little distinguishable impact on clinical outcomes in this preliminary study.
5

Evolução das doses no ambiente do Reator IEA-R1 e tendências com base nos resultados atuais / The evolution of doses in THE IEA-R1 reactor environment and tendencies based on the current results

Toyoda, Eduardo Yoshio 19 May 2016 (has links)
O Ipen/Cnen-SP possui um Reator de Pesquisa(IEA-R1) em operação desde 1957. Ele utiliza água leve como blindagem, moderador e como fluido refrigerante, o volume desta piscina é de 273m3. Até 1995 a operação do Reator era descontinua, ou seja, operava diariamente sendo desligado no final do dia, a uma potência de 2,0 MW. A partir daquele ano, após algumas modificações de segurança, o Reator passou a operar de forma continua, ou seja, de segunda-feira a quarta-feira sem ser desligado, totalizando 64 horas semanais. A potência também foi aumentando até 4,5 MW em 2012. Em virtude dessas alterações, a saber, operação contínua e do aumento da potência, as doses dos trabalhadores aumentaram e por isso foram realizados vários estudos para diminui-las. Estudos demonstraram que uma das principais limitações para operação de um reator em potência elevada, provém das radiações gama emitidas pelo sódio-24. Outros elementos como magnésio-27, Alumínio-28, Argônio-51, contribuem de forma considerável para a atividade da água da piscina. A introdução de uma camada de água quente em sua superfície, estável e isenta de elementos radioativos com 1,5m a 2m de espessura constituiria uma blindagem às radiações provenientes dos elementos radioativos dissolvidos na água. Estudos de otimização provaram que a instalação da camada quente não era necessária para o regime e potência atual de operação do Reator, pois outros procedimentos adotados eram mais eficazes. A partir desta decisão o serviço de Proteção Radiológica do Reator IEA-R1, montou um programa de avaliação das doses para certificar-se de que elas se mantinham em valores razoáveis baseados em princípios estabelecidos em normas nacionais e internacionais. O intuito deste trabalho é realizar uma análise das doses individuais dos IOE (Individuo Ocupacionalmente Expostos), considerando as mudanças no regime de operação do Reator e sugerir opções de proteção e segurança, viáveis em primeira instância, para reduzir as doses analisadas, visando se chegar aos níveis de referencia de 3 mSv/ano adotados pela instalação em apreço. / The IPEN / CNEN-SP have a Nuclear Research Reactor-NRR named IEA-R1, in operation from 1957. It is an open swimming pool reactor using light water as shielding, moderator and as cooling, the volume of this pool is 273m3.Until 1995 the reactor operated daily at a power of 2,0 MW. From June of that year, after a few safety modifications the reactor began operating in continuous way from Monday to Wednesday without shutdown totalizing 64 hours per week and the power was increased to 4,5MW also. Because of these changes, continuous operation and increased power, workers´ doses would tend to increase. In the past several studies were conducted seeking ways to reduce the workers´ doses. A study was made on the possibility to introduce a shielding at the top of the reactor core with a hot water layer. Studies have shown that a major limitation for operating a reactor at high power comes from the gamma radiation emitted by the sodium-24. Other elements such as magnesium-27, aluminum-28, Argon-51, contribute considerably to the water activity of the pool. The introduction of a hot water layer on the swimming pool would form a layer of surface, stable and free of radioactive elements with a 1.5m to 2m thickness creates a shielding to radiation from radioactive elements dissolved in water. Optimization studies proved that the installation of the hot layer was not necessary for the regime and the current power reactor operation, because other procedures adopted were more effective. From this decision the Radiological Protection Reactor Team, set up a dose assessment program to ensure them remained in low values based on principles established in national and international standards. The purpose of this paper is to analyze the individual doses of OEI (Occupationally Exposed Individual), which will be checked increasing doses resulting from recent changes in reactor operation regime and suggested viable safety and protection options, in the first instance to reducing the doses in question aimed at the goal of reaching acceptable doses belonging to the reference level of 3 mSv/y taken by the reactor facility.
6

Evolução das doses no ambiente do Reator IEA-R1 e tendências com base nos resultados atuais / The evolution of doses in THE IEA-R1 reactor environment and tendencies based on the current results

Eduardo Yoshio Toyoda 19 May 2016 (has links)
O Ipen/Cnen-SP possui um Reator de Pesquisa(IEA-R1) em operação desde 1957. Ele utiliza água leve como blindagem, moderador e como fluido refrigerante, o volume desta piscina é de 273m3. Até 1995 a operação do Reator era descontinua, ou seja, operava diariamente sendo desligado no final do dia, a uma potência de 2,0 MW. A partir daquele ano, após algumas modificações de segurança, o Reator passou a operar de forma continua, ou seja, de segunda-feira a quarta-feira sem ser desligado, totalizando 64 horas semanais. A potência também foi aumentando até 4,5 MW em 2012. Em virtude dessas alterações, a saber, operação contínua e do aumento da potência, as doses dos trabalhadores aumentaram e por isso foram realizados vários estudos para diminui-las. Estudos demonstraram que uma das principais limitações para operação de um reator em potência elevada, provém das radiações gama emitidas pelo sódio-24. Outros elementos como magnésio-27, Alumínio-28, Argônio-51, contribuem de forma considerável para a atividade da água da piscina. A introdução de uma camada de água quente em sua superfície, estável e isenta de elementos radioativos com 1,5m a 2m de espessura constituiria uma blindagem às radiações provenientes dos elementos radioativos dissolvidos na água. Estudos de otimização provaram que a instalação da camada quente não era necessária para o regime e potência atual de operação do Reator, pois outros procedimentos adotados eram mais eficazes. A partir desta decisão o serviço de Proteção Radiológica do Reator IEA-R1, montou um programa de avaliação das doses para certificar-se de que elas se mantinham em valores razoáveis baseados em princípios estabelecidos em normas nacionais e internacionais. O intuito deste trabalho é realizar uma análise das doses individuais dos IOE (Individuo Ocupacionalmente Expostos), considerando as mudanças no regime de operação do Reator e sugerir opções de proteção e segurança, viáveis em primeira instância, para reduzir as doses analisadas, visando se chegar aos níveis de referencia de 3 mSv/ano adotados pela instalação em apreço. / The IPEN / CNEN-SP have a Nuclear Research Reactor-NRR named IEA-R1, in operation from 1957. It is an open swimming pool reactor using light water as shielding, moderator and as cooling, the volume of this pool is 273m3.Until 1995 the reactor operated daily at a power of 2,0 MW. From June of that year, after a few safety modifications the reactor began operating in continuous way from Monday to Wednesday without shutdown totalizing 64 hours per week and the power was increased to 4,5MW also. Because of these changes, continuous operation and increased power, workers´ doses would tend to increase. In the past several studies were conducted seeking ways to reduce the workers´ doses. A study was made on the possibility to introduce a shielding at the top of the reactor core with a hot water layer. Studies have shown that a major limitation for operating a reactor at high power comes from the gamma radiation emitted by the sodium-24. Other elements such as magnesium-27, aluminum-28, Argon-51, contribute considerably to the water activity of the pool. The introduction of a hot water layer on the swimming pool would form a layer of surface, stable and free of radioactive elements with a 1.5m to 2m thickness creates a shielding to radiation from radioactive elements dissolved in water. Optimization studies proved that the installation of the hot layer was not necessary for the regime and the current power reactor operation, because other procedures adopted were more effective. From this decision the Radiological Protection Reactor Team, set up a dose assessment program to ensure them remained in low values based on principles established in national and international standards. The purpose of this paper is to analyze the individual doses of OEI (Occupationally Exposed Individual), which will be checked increasing doses resulting from recent changes in reactor operation regime and suggested viable safety and protection options, in the first instance to reducing the doses in question aimed at the goal of reaching acceptable doses belonging to the reference level of 3 mSv/y taken by the reactor facility.
7

Cálculo independente das unidades monitoras e tempos de tratamento em radioterapia

MUELLER, MARCIO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:40Z (GMT). No. of bitstreams: 1 10283.pdf: 9865329 bytes, checksum: 191fbb39805c2da7c652e51119c0e642 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
8

Dosimetria termoluminescente de neutrons com fluorita natural

MUCCILLO, REGINALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:54Z (GMT). No. of bitstreams: 1 01009.pdf: 1210828 bytes, checksum: 081f4bbe930a4a873ba638585746e8b9 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
9

Cálculo independente das unidades monitoras e tempos de tratamento em radioterapia

MUELLER, MARCIO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:40Z (GMT). No. of bitstreams: 1 10283.pdf: 9865329 bytes, checksum: 191fbb39805c2da7c652e51119c0e642 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
10

Dosimetria termoluminescente de neutrons com fluorita natural

MUCCILLO, REGINALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:54Z (GMT). No. of bitstreams: 1 01009.pdf: 1210828 bytes, checksum: 081f4bbe930a4a873ba638585746e8b9 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP

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