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1.
Appl Radiat Isot ; 198: 110832, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37182393

RESUMO

Proton induced reaction data are needed in the optimization of various radioisotope production routes, among others. In this work, the evaluation of proton-induced reactions on 111Cd between 1 and 100 MeV using the TALYS code system within an iterative Bayesian Monte Carlo (iBMC) framework, is presented. The method involves the simultaneous variation of a large number of nuclear reaction models included in the TALYS code system as well as their parameters. Each random TALYS calculation yields a vector of calculated values of cross section observables as well as the angular distributions, among others, which were compared with corresponding vectors of carefully selected differential experimental data for reaction channels where data were available. The random nuclear data file with the maximum likelihood function value obtained from combining the individual χ2s computed for the considered reaction channels was chosen as the parent vector and the starting point for the generation of a further set of random TALYS calculations. This was repeated multiple times until a targeted convergence of 5% was reached. The final evaluated file was compared with available experimental data from the EXFOR database as well as with the evaluations from the TENDL-2021 and JENDL5.0 libraries, and found to compare favorably.


Assuntos
Braquiterapia , Cádmio , Prótons , Teorema de Bayes , Radioisótopos
2.
Radiat Prot Dosimetry ; 126(1-4): 35-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17496294

RESUMO

In recent years, an increasing number of applications involving fast neutrons have been developed or are under consideration, e.g. radiation treatment of cancer, neutron dosimetry at commercial aircraft altitudes, soft-error effects in computer memories, accelerator-driven transmutation of nuclear waste and energy production and determination of the response of neutron detectors. Data on light-ion production in light nuclei such as carbon, nitrogen and oxygen are particularly important in calculations of dose distributions in human tissue for radiation therapy at neutron beams, and for dosimetry of high-energy neutrons produced by high-energy cosmic radiation interacting with nuclei (nitrogen and oxygen) in the atmosphere. When studying neutron dose effects, it is especially important to consider carbon and oxygen, since they are, by weight, the most abundant elements in human tissue. Preliminary experimental double-differential cross sections of inclusive light-ion (p, d, t, (3)He and alpha) production in carbon induced by 96-MeV neutrons have been presented. Energy spectra were measured at eight laboratory angles: 20, 40, 60, 80, 100, 120, 140 and 160 degrees. Measurements were performed at The Svedberg Laboratory (TSL), Uppsala, using the dedicated MEDLEY experimental setup. The authors have earlier reported experimental double-differential cross sections of inclusive light-ion production in oxygen. In this paper, the deduced kerma coefficients for oxygen has been presented and compared with reaction model calculations.


Assuntos
Carbono/química , Modelos Químicos , Nêutrons , Oxigênio/química , Monitoramento de Radiação/métodos , Carbono/efeitos da radiação , Simulação por Computador , Oxigênio/efeitos da radiação , Doses de Radiação
3.
Thorac Cardiovasc Surg ; 36(1): 1-4, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3287681

RESUMO

In order to detect changes in renal perfusion and function in the postoperative period of open heart surgery, a prospective study of 21 patients following open heart surgery was performed. Cardiac output, renal blood flow, glomerular filtration and renal function parameters were determined during intermittent positive pressure ventilation (IPPV), and during spontaneous ventilation (SV). During IPPV, renal perfusion was found to be substantially decreased. The glomerular filtration rate was also reduced, but to a lesser extent, implying that the changes were due to a selective increase in postglomerular vascular resistance. The clearances of urea and creatinine were decreased during IPPV, but the clearances of osmoles and potassium were higher. The reabsorption of sodium, potassium and osmoles were also decreased during IPPV, but not that of urea. These findings are consistent with the development of increased renal venous pressure during IPPV, caused by impeded venous return to the heart. In the low cardiac output range a cardiac index in excess of 0.5l/min/m2 during IPPV seems necessary to achieve the same renal perfusion as during SV.


Assuntos
Ponte de Artéria Coronária , Ventilação com Pressão Positiva Intermitente/efeitos adversos , Rim/fisiopatologia , Respiração com Pressão Positiva/efeitos adversos , Injúria Renal Aguda/etiologia , Humanos , Perfusão , Cuidados Pós-Operatórios , Estudos Prospectivos , Urodinâmica
4.
Scand J Thorac Cardiovasc Surg ; 21(3): 207-13, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3438717

RESUMO

A multivariate analysis of 130 consecutive patients operated during one month in our hospital was carried out to determine the influence of age and blood flow during cardiopulmonary bypass on the renal response to cardiac surgery. The postoperative level of serum creatinine could be related to three variables: preoperative serum creatinine, age and lowest blood flow during cardiopulmonary bypass. A higher blood flow is needed during cardiopulmonary bypass in older patients and in patients with a raised pre-operative serum creatinine to prevent deterioration in renal function postoperatively. A nomogram is given for the lowest blood flow during CPB, corrected for age and the pre-operative serum creatinine level, which will result in a desired postoperative serum creatinine of 110 mumol/l.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Rim/fisiologia , Adulto , Fatores Etários , Idoso , Circulação Sanguínea , Creatinina/sangue , Humanos , Pessoa de Meia-Idade
5.
Thorac Cardiovasc Surg ; 33(5): 283-7, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2416082

RESUMO

The influence of 51 preoperative, peroperative and postoperative variables on the development of serious acute renal failure (ARF) following open heart surgery was studied. Although a large number of significant variables was found, a logit-model with only 2 explanatory variables showed an almost perfect fit. With this model the chances of serious ARF up to 90% were estimated. The results suggest that a critical circulation is the main cause of serious ARF. Furthermore, a reduced ability to cope with a critical circulation without renal failure plays an important role in the pathogenesis. There is a higher risk of serious ARF for patients older than 70, especially when circulatory support with dopamine is needed.


Assuntos
Injúria Renal Aguda/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/mortalidade , Idoso , Humanos , Modelos Biológicos , Complicações Pós-Operatórias , Estatística como Assunto
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