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1.
Chinese Journal of Radiological Medicine and Protection ; (12): 784-789, 2021.
Article in Chinese | WPRIM | ID: wpr-910394

ABSTRACT

Nanodosimetry, a new discipline developed on the basis of microdosimetry, is based on the structural characteristics of particle tracks and studies on the probability distribution of ionization pairs in a specific volume to characterize the damage degree of DNA strand. Now nanodosimetric quantities, which may be measured, gradually form the concept such as ionization cluster size, ionizing cluster size distribution and complementary cumulative probability distribution etc. This paper aims to establish and explain the relationship between nanodosimetry and DNA damage and repair. On the basis of reviewing the current measurement and calculation method of nanodosimetry, this paper summarized the development trend and application prospect of nanodosimetry, and put forward the future research direction of nanodosimetry.

2.
Ciênc. rural ; 47(2): 20160170, 2017. tab, graf
Article in English | LILACS | ID: biblio-828462

ABSTRACT

ABSTRACT: The aim of this study was to identify soybean sowing dates on which there was low water surplus risk. The crop was raised on a Haplic Planosol soil in the Central Depression of Rio Grande do Sul, Brazil. Soybean development simulations and daily water balances were calculated for different sowing dates from August 1968 to July 2012. Water surplus data was subjected to BoxPlot analyses and Scott-Knott tests at a 5% error probability. Exponential, gamma, lognormal, normal and Weibull functions were tested and the best fits to the data were obtained for both subperiods and total cycle. The highest number of fits for the development cycle and subperiods were obtained using the gamma and weibull functions, respectively. For sowing carried out after November 1, there was a low water surplus risk in the sowing-emergence subperiod. The risk of water surplus during the development cycle decreased with the advance of the sowing date.


RESUMO: O objetivo deste trabalho foi identificar as datas de semeadura com menor risco de ocorrência de excesso hídrico para a cultura da soja, em um Planossolo Háplico na Depressão Central do Rio Grande do Sul. A simulação do desenvolvimento da soja e o balanço hídrico sequencial diário foram realizados para diferentes datas de semeadura em cada ano do período de agosto de 1968 a julho de 2012. Os dados dos dias de excesso hídrico, obtidos para o ciclo da cultura, foram submetidos à análise BoxPlot e teste de Scott-Knott a 5% de probabilidade de erro. Foram testadas as funções exponencial, gama, lognormal, normal e weibull, verificando-se a de melhor ajuste aos dados obtidos para os subperíodos e ciclo total. O maior número de ajustes para o ciclo de desenvolvimento e para os subperíodos foram obtidos para as funções gama e weibull, respectivamente. As semeaduras, realizadas após o dia primeiro de novembro, apresentam menor risco de ocorrência de excesso hídrico no subperíodo semeadura-emergência. O risco de ocorrência de excesso hídrico para o ciclo de desenvolvimento é decrescente, conforme o avanço da data de semeadura.

3.
Article in English | IMSEAR | ID: sea-165358

ABSTRACT

Background: Due to severe pain, patients are impatient in several wings sporadically and more frequently in emergency wing of the hospitals. To efficiently administer in such environment and the hospital management seeks helpful strategies. The queuing concepts and related methodologies can help as this article has demonstrated by an analysis and interpretation of real data from a hospital in Malta. Methods: The queuing concepts are probabilistic and statistical ideas based approach. They require configuration of the rate and pattern of arriving patients, the rate and pattern of the service, the number of channels serving, the capacity of the waiting room, and the criterion for selecting patients for service etc. New ideas are presented in this article to manage in various scenarios of real life emergency operations. The pertinent queuing concepts and tools are made easier for the readers to comprehend and practice in their own situations in which they notice that the patients are impatient in their waiting. Results: Using the new ideas and formulas of this article, the data in the emergency wing of a hospital in Malta (a largest island of an archipelago situated in the center of the Mediterranean with a total population of a million) are analyzed and interpreted. The results clearly explain why there were a prolonged waiting times at the emergency department creating public dissatisfaction and patients were leaving without waiting to be seen. The total time spent by non-urgent patients with nurse and casualty officer is more in the second shift and lesser and lesser in the third and fourth shifts. The interactive time with a nurse by patient is statistically same in all three types: life-threatening, non-life threatening but urgent, and non-urgent. Very strikingly, the patients in all three groups wait longer to be seen by the nurse in shift three and lesser time in shifts two or four. Conclusion: In 21st century with flourishing globalized medical tourism, a standardized approach to minimize efficiently the waiting time in emergency and other wings of the hospitals in developing as much as in developed nations is a necessity as this auricle has pointed out. The impediments and the remedies for an efficient standardization are overdue.

4.
Ciênc. rural ; 39(8): 2428-2434, nov. 2009. tab
Article in Portuguese | LILACS | ID: lil-529899

ABSTRACT

Os objetivos deste estudo foram ajustar e selecionar funções de densidade probabilística que caracterizem a estrutura diamétrica desse fragmento e das espécies: Cedrela fissilis (Cedro), Luehea divaricata (Açoita Cavalo), Gochnatia polymorpha (Cambará), Sebastiania commersoniana (Branquilho) e Casearia sylvestris (Cafezeiro) de um fragmento de Floresta Ombrófila Mista com 15,24ha, localizado em Curitiba, Paraná. Para avaliar a distribuição diamétrica dessa floresta e das cinco espécies selecionadas, foram ajustadas sete funções probabilísticas para intervalos de classe de 5cm. Segundo os critérios de seleção adotados, o modelo que melhor representou a distribuição diamétrica para toda a floresta, o cedro, o cambará e o branquilho foi o de Weber; para o cafezeiro, a função Gamma (Adaptada) foi a mais eficiente e para o açoita cavalo nenhuma dessas funções foi aderente. O branquilho, o açoita cavalo, o cafezeiro e a floresta como um todo apresentaram distribuição em "J" invertido ou decrescente. Entretanto, o cedro e o cambará apresentaram distribuição tendendo à unimodalidade com forte assimetria à direita.


The objective of this study was to adjust and select probability density functions that characterize the diametric structure of this forest fragment and for the species: Cedrela fissilis, Luehea divaricata, Gochnatia polymorpha, Sebastiania commersoniana and Casearia sylvestris for a 15.24 hectare fragment of Mixed Ombrophylous Forest, located in Curitiba, State of Paraná. In order to evaluate the diametric distributions of this forest and the five selected species, seven probability functions were adjusted for 5cm class intervals. According to the criteria of selection adopted, the model that best represented the diametric distributions for the whole forest, Cedrela fissilis, Gochnatia polymorpha and Sebastiania commersoniana was the Weber model; for Casearia sylvestris, the Gamma function (adapted) was the most efficient, and for Luehea divaricata, none of these functions showed adherence. The Sebastiania commersoniana, Luehea divaricata, Casearia sylvestris and the forest as a whole showed inverted "J" or decreasing distribution, while, Cedrela fissilis and Gochnatia polymorpha showed an almost unimodal distribution with a strong asymmetry to the right.

5.
Ciênc. agrotec., (Impr.) ; 31(5): 1297-1302, set.-out. 2007. graf, tab
Article in Portuguese | LILACS | ID: lil-466518

ABSTRACT

Estudos probabilísticos envolvendo variáveis climáticas são de extrema importância para as atividades da agropecuária, construção civil, turismo, transporte, dentre outros. Visando contribuir para o planejamento da agricultura irrigada, este trabalho teve como objetivos comparar distribuições de probabilidade ajustadas às séries históricas decendiais e mensais, e estimar as precipitações prováveis para o município de Barbacena, MG. Foram estudados os meses de dezembro, janeiro e fevereiro, no período de 1942 a 2003, constituindo-se séries históricas com 62 anos de observações. As lâminas diárias foram totalizadas em períodos mensais e decendiais, sendo aplicadas as distribuições log-Normal 2 parâmetros, log-Normal 3 parâmetros e Gama. Para avaliar a adequabilidade das distribuições, nos períodos estudados, utilizou-se o teste de Qui-quadrado (chi2), ao nível de 5 por cento de significância. As precipitações prováveis foram estimadas para cada período estudado utilizando a distribuição que apresentou o menor valor de chi2, nos níveis de probabilidade de excedência de 75, 90 e 98 por cento. A distribuição Gama foi a que melhor se ajustou aos dados. O estudo de precipitações prováveis é uma boa ferramenta no auxílio da tomada de decisão quanto ao planejamento e uso da irrigação.


Probabilistic studies involving climatic variables are of extreme importance for farming activities, construction, tourism, among others. Seeking to contribute for the planning of irrigate agriculture, this work had as objectives to compare adjusted probability distribution models to the monthly and decennial historical series and to estimate the probable rainfall for the Barbacena County, Minas Gerais State, Brazil. Rainfall data of December, January and February, from 1942 to 2003, were studied, constituting historical series with 62 years of observations. Daily rainfall depths were added for 10 and 30 days, applying Gama, log-Normal 2 and log-Normal 3 parameters probability distribution models. Probability distributions models, were compared with Qui-square statistical test, at 5 percent significance level. Probable rainfall was estimated for each period, using the best distribution, which was evaluated based on the smallest Qui-square value, for the probability occurrence levels of 75, 90 and 98 percent. Gama probability distribution was the most adequate model.

6.
Neotrop. entomol ; 32(1): 107-115, Jan.-Mar. 2003. tab
Article in Portuguese | LILACS | ID: lil-513440

ABSTRACT

O conhecimento do modelo de distribuição espacial de pragas na cultura é fundamental para estabelecer um plano adequado de amostragem seqüencial e, assim, permitir a correta utilização das estratégias de controle e a otimização das técnicas de amostragem. Esta pesquisa objetivou estudar a distribuição espacial de lagartas de Alabama argillacea (Hübner) na cultura do algodoeiro, cultivar CNPA ITA-90. A coleta de dados ocorreu durante o ano agrícola de 1998/99 na Fazenda Itamarati Sul S.A., localizada no município de Ponta Porã, MS, em três diferentes áreas de 10.000 m² cada uma. Cada área amostral foi composta de 100 parcelas com 100 m² cada. Foi realizada semanalmente a contagem das lagartas pequenas, médias e grandes, encontradas em cinco plantas por parcela. Os índices de agregação (razão variância/média e índice de Morisita), o teste de qui-quadrado com o ajuste dos valores encontrados e esperados às distribuições teóricas de freqüência (Poisson, binomial positiva e binomial negativa), mostraram que todos os estádios das lagartas estão distribuídos de acordo com o modelo de distribuição contagiosa, ajustando-se ao padrão da Distribuição Binomial Negativa durante todo o período de infestação.


The knowledge of the dispersion pattern of the pests on a crop is fundamental for establishing an appropriated sequential sampling method. Also it permits the correct utilization of control strategies and optimization of sampling techniques. The objective of this research was to determine the spatial distribution of larvae of Alabama argillacea (Hübner) on cotton crop, CNPA ITA-90 cultivar. During the 1998/99 growing season a sampling system was applied in three experimental areas located at Itamarati Sul S.A. farm in the region of Ponta Porã, estate of Mato Grosso do Sul, Brazil. The areas measured 1 ha and contained 100 plots with 100 m². In a weekly basis the number of small, medium and large larvae were counted on five plants per plot. The aggregation indexes (variance/mean ratio and Morisita index), the chi-square test and the adjust of observed and expected values to theoretical distributions of frequencies (Poisson, positive binomial and negative binomial) showed that all stages of cotton leafworm larvae were distributed according to the contagious model, fitting the Negative Binomial Distribution during the whole period of infestation.

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