Application of DDPM in artificial intelligence image data augmentation of medical device / 中国医学装备

Medical device imaging data augmentation is a method of expanding existing datasets by generating new data samples,which is of great significance for improving the performance of artificial intelligence(AI)medical device-related models and clinical application effects.However,traditional data augmentation methods are usually limited by the quality,realism,and diversity of generated samples.Denoising diffusion probabilistic model(DDPM)is a generative model based on the noise diffusion process,and its main idea is to generate samples with high quality by modelling the sampling process of the target distribution as a process of progressive denoising from the noise distribution.The basic principles and working mechanisms of DDPM were reviewed,the application scenarios of this method in AI medical device data augmentation were analyzed,and its advantages,challenges,and future development directions were explored to provide a reference for the field of AI medical device data augmentation.

Application of Bayesian probabilistic linkage model in birth and death data linking / 上海预防医学

ObjectiveTo elucidate the principles and methods of the Bayesian probabilistic linkage model， and to demonstrate the effect of applying the model in linking birth and death data. MethodsThrough the Shanghai birth and death registration system， data of 199 025 infants born in 2017 and 1 512 infants who died in 2017 and 2018 were collected. After cleaning the data， the data were divided into monthly blocks and fully linked. The Jaro-Winkler algorithm and Euclidean distance were employed to measure the similarity of fields for matching. A Bayesian probabilistic linkage model was constructed and the linking effect was evaluated using a confusion matrix. ResultsUsing the Bayesian probabilistic linkage model， the birth and death data of infants were effectively linked， revealing that 36.71% of infants who died in Shanghai were born outside the city， and the probability of infant death was 2.6‰. The confusion matrix of the test set showed a recall rate of 0.86， precision of 0.76， and an F-score of 0.81. ConclusionThe practical application of Bayesian probabilistic linkage demonstrates a good model performance， enabling the establishment of birth-death cohorts that more accurately reflect the true levels of infant mortality. Utilizing this technique to integrate data from different departments can effectively improve research efficiency in the field of public health.

Probabilistic Tractography Between Nucleus Accumbens and Other Reward-related Brain Areas in Malay Female Adolescents

@#Introduction: Studies show that adolescents are more reward sensitive compared to other age groups. The nucleus accumbens (NAcc) has been identified as a key brain area involved in reward through its connectivity to other reward-related brain areas. Our study aimed to characterise the white matter structural connectivity of nucleus accumbens with brain areas that are most often associated with reward in female adolescents. Methods: Fifteen healthy female Malay adolescents were recruited and underwent diffusion-weighted brain scanning. Two behaviour scales were also given to verify typical reward responsiveness. Then, probabilistic tractography and NAcc segmentation were performed on the data using FMRIB Software Library (FSL). Probabilistic tractography was performed to determine the relative connection probability of nucleus accumbens (NAcc) to areas shown to be associated with reward, namely amygdala, anterior cingulate cortex (ACC), medial orbitofrontal cortex (mOFC), hippocampus, ventrolateral prefrontal cortex (vlPFC) and dorsolateral prefrontal cortex (dlPFC). Connectivity-based segmentation of NAcc was performed to determine the spatial distribution of its connectivity with the target brain areas according to the highest connection probability. Results: The highest relative connection probability was found between NAcc to mOFC, while the NAcc parcellation showed the widest distribution of connection to mOFC compared to the other five targets on both sides of the brain. Conclusion: Our findings demonstrated the strongest structural connectivity and widest distribution between NAcc and mOFC compared with other brain areas related to reward. This study’s findings could be used as baseline to compare with people with atypical reward circuit problems.

Dietary exposure assessment of deoxynivalenol in wheat flour and its products sold in Shanghai / 上海预防医学

ObjectiveTo investigate the pollution level of deoxynivalenol （DON） in wheat flour and its products sold in Shanghai， and to assess the health risks of DON exposure for residents in Shanghai who ingested DON from wheat flour and its products. MethodsRisk monitoring data of DON in wheat flour and its products sold in Shanghai from 2017 to 2021 were combined with the consumption data of wheat flour and its products by Shanghai residents. A probabilistic assessment method was used to assess dietary exposure of DON in wheat flour and its products. ResultsThe overall detection rate of DON in wheat flour and its products was 77.3% （1 041/1 347）， with a mean concentration of 226.3 μg·kg-1， P50 of 130.0 μg·kg-1 and a maximum value of 3 080.0 μg·kg-1. The mean daily exposure and 95th percentile daily exposure （by body weight） of DON from wheat flour and its products in Shanghai residents were 0.279 μg·kg-1 and 1.146 μg·kg， accounting for 27.9% and 114.6% of the daily tolerable intake of DON TDI， 1 μg·kg， respectively. The probability assessment results indicated that 6.1% of the whole population in Shanghai had DON exposure exceeding the TDI value. Among them， 12.8% of the population aged 6 years old and below， 16.4% of the population aged between 7 and 17 years old， 3.9% of the population aged between 18 and 59 years old and 3.2% of the population aged 60 years old and above exceeded the TDI value for daily DON exposure through wheat flour and its products. ConclusionCertain populations in Shanghai may face certain health risks from daily DON intake wheat flour and its products. Special attention should be paid to the health risk of daily DON exposure through wheat flour and its products for individuals age below 18 years old .

Enfermedades crónicas no transmisibles en Argentina: modelo y pronósticos por sexo y edad

Las enfermedades crónicas no transmisibles (ECNT) son padecimientos intransferibles por contacto de persona a persona y se caracterizan por su evolución generalmente lenta. En Argentina, son la principal causa de muerte y discapacidad, solo dos grupos de estas (cardiovasculares y cáncer) son responsables de la mitad del total de las muertes y del 27 % de los años de vida potencialmente perdidos (AVPP). El objetivo general de este trabajo cuantitativo, transversal y descriptivo es describir y analizar el perfil según edad y sexo de las tasas de mortalidad por ECNT en Argentina, a partir del modelo para datos funcionales (MDF) de Hyndman y Ullah (2007). Dicho método permite, además, pronosticar el comportamiento de los índices al considerar los cambios relacionados con la edad y la tendencia observada a través del tiempo. La diferencia relativa en la mortalidad entre el inicio del periodo de estudio (1985 a 2014) y el pronóstico para el año 2025 indica que, de continuar el comportamiento imperante, se alcanzarían descensos de alrededor del 50 % para hombres de entre 30 y 50 años y del 20 % para mujeres de entre 20 y 35 años. Estos resultados apuntan, de un modo más general, a que las tasas de mortalidad de los grupos etarios menores de 70 años, cuyas defunciones se denominan prematuras, son claramente descendentes para ambos sexos, aunque el caso de los hombres destaca, pues, si bien presentan mayores tasas de mortalidad por ECNT, el descenso es más marcado.

Chronic Non-Communicable Diseases (NCD) are diseases that are not transmitted from person to person and that are characterized by their generally slow evolution. In Argentina, NCDs are the main cause of death and disability, only two groups of causes (cardiovascular and cancer) are responsible for half of all deaths and 27 % of years of life potentially lost (YPLL). The general objective of this work, a quantitative, cross-sectional and descriptive study, is to describe and analyze the profile by age and sex of the mortality rates due to NCD in men and women in Argentina, based on the implementation of the model for functional data (MDF) by Hyndman and Ullah (2007). This model also makes it possible to forecast the behavior of mortality rates for both sexes, taking into account the changes related to age and the trend observed over time during the period 1985-2014. The relative difference in mortality between the beginning of the study period and the forecast for the year 2025 indicates that, if the prevailing behavior in rates continues, decreases of around 50 % would be achieved for men between 30 and 50 years of age. While for women the greatest decreases (of around 20 %) would be observed between the ages of 20 and 35. These results would indicate, in a more general way, that the behavior of the mortality rates of the age groups under 70 years, whose deaths are called ''premature", is of a clear decrease for both sexes, highlighting that, in the case of men, although they have higher NCD mortality rates, this decrease is more marked.

La fecundidad en la ciudad de Rosario, Argentina: proyecciones y retroproyecciones de la tasa global de fecundidad y las tasas específicas de fecundidad / Fertility in Rosario City, Argentina: Projections and retro-projections of the global fertility rate and specific fertility rates

Resumen El estudio que da lugar al presente artículo surge a partir de los resultados obtenidos en el marco de un convenio de colaboración firmado por la Dirección General de Estadística de la Municipalidad de Rosario y la Escuela de Estadística de la Facultad de Ciencias Económicas y Estadística de la Universidad Nacional de Rosario. Entre sus objetivos, se plantea el de obtener pronósticos probabilísticos de la fecundidad para la Ciudad de Rosario. Para ello, con base en estadísticas vitales, estimaciones y proyecciones de población se construyen escenarios probables, pasados y futuros, tanto para la tasa global de fecundidad como para las tasas específicas de fecundidad. Los resultados de este estudio, basados en la aplicación de modelos probabilísticos de pronóstico, permiten conocer estructuras y tendencias, pasadas y futuras de la fecundidad, de modo que puedan generarse diagnósticos que sean de utilidad para la evaluación y gestión del sistema de salud o bien para el desarrollo de nuevas políticas públicas. Los resultados indican que Rosario tuvo, tiene y seguirá teniendo un cambio en los patrones de fecundidad más rápido y marcado que el promedio nacional. Si bien este hecho es esperable, en un contexto signado por los avances en la salud pública, que permiten acceder a más y mejor atención en salud reproductiva, la metodología aquí empleada se basa únicamente en la extrapolación de las tendencias, por ello la retroproyección debe ser analizada cuidadosamente. Con posterioridad, en la sección metodológica, se presentan los modelos probabilísticos de pronóstico que se emplean para la obtención de resultados.

Abstract The study that gives rise to this article arises from the results obtained in the framework of a collaboration agreement signed by the Statistical Office of Rosario City and the School of Statistics of the Faculty of Economic Sciences and Statistics (National University of Rosario). Among its objectives is to obtain probabilistic fertility forecasts for Rosario City. For this, based on vital statistics, estimates and population projections, probable scenarios, past and future, are constructed, both for the global fertility rate and the specific fertility rates. The results of this study, based on the application of probabilistic prognostic models, allow to know structures and trends, past and future, of fertility, so that diagnoses can be generated that are useful for the evaluation and management of the health system or good for the development of new public policies. The results indicate that Rosario had, has and will continue to have a change in fertility patterns faster and more marked than the national average. Although this fact is to be expected in a context marked by advances in public health (which allow access to more and better reproductive health care), the methodology used here is based solely on the extrapolation of trends, therefore, the backprojection must be carefully analyzed.

Performance analysis of professional soccer goalkeepers by Composition of Probabilistic Preferences / Análise de desempenho de goleiros do futebol profissional por Composição Probabilística de Preferências / Análisis del rendimiento de porteros de fútbol profesional por Composición Probabilística de Preferencias

ABSTRACT This research aims to assist managers and technical commissions to choose professional soccer goalkeepers. A sample of 64 goalkeepers playing in Argentina and Brazil was studied. Their performance in the matches of two seasons were analyzed considering three criteria: goals against per minute played, percentage of goals and percentage of matches without conceded goals. The Composition of Probabilistic Preferences (CPP) was the method chosen for modeling, considering the random variability in the problem data and in football, considered one of the most unpredictable sports. CPP allowed to compare the choice based on the data analysis to the latest goalkeeper call-ups for these countries' national teams. The selected goalkeepers corresponded to those presenting the best individual performance, which confirms the model.

RESUMO Esta pesquisa teve como objetivo auxiliar gestores e comissões técnicas na escolha de goleiros do futebol profissional. Foi estudada uma amostra de 64 goleiros que atuam na Argentina e no Brasil. Foram analisados seus desempenhos em jogos de duas temporadas, considerando três critérios: gols sofridos por minutos jogados, percentual de gols evitados e percentual de partidas sem sofrer gols. A Composição Probabilística de Preferências foi o método escolhido para a modelagem, por considerar a variabilidade aleatória dos dados do problema e do futebol, considerado um dos esportes mais imprevisíveis. A aplicação comparou a escolha baseada na análise dos dados com as últimas convocações de goleiros para as seleções desses países. Os goleiros selecionados corresponderam aos de melhor desempenho individual, confirmando o modelo.

RESUMEN Esta investigación tuvo como objetivo ayudar a gerentes y comisiones técnicas para elegir a los porteros de fútbol profesional. Una muestra de 64 porteros de Argentina y Brasil fue estudiada. Las actuaciones en los partidos de dos temporadas fueran analizadas, considerando tres criterios: goles concedidos por minutos jugados, porcentaje de goles evitados y porcentaje de partidos en los que al portero no le encajaron goles. La Composición Probabilística de Preferencias fue el método elegido, considerando la variabilidad aleatoria de los datos del problema y del fútbol, considerado uno de los deportes más impredecibles. La aplicación comparó la muestra con las últimas convocatorias de porteros de las selecciones nacionales de estos países. Los porteros seleccionados correspondieron a los de mejor rendimiento individual, confirmando el modelo.

Discrimination of lung cancer and adjacent normal tissues based on permittivity by optimized probabilistic neural network / 南方医科大学学报

OBJECTIVE@#To propose a probabilistic neural network classification method optimized by simulated annealing algorithm (SA-PNN) to discriminate lung cancer and adjacent normal tissues based on permittivity.@*METHODS@#The permittivity of lung tumors and the adjacent normal tissues was measured by an open-ended coaxial probe, and the statistical dependency (SD) algorithm was used for frequency screening.The permittivity associated with the selected frequency points was taken as the characteristic variable, and SA-PNN was used to discriminate lung cancer and the adjacent normal tissues.@*RESULTS@#Three frequency points, namely 984 MHz, 2724 MHz and 2723 MHz, were selected by SD algorithm.SA-PNN was used to discriminate 200 samples with the permittivity at the 3 frequency points as the characteristic variable.After 10-fold cross-validation, the final discrimination accuracy was 92.50%, the sensitivity was 90.65%, and the specificity was 94.62%.@*CONCLUSIONS@#Compared with the traditional probabilistic neural network, BP neural network, RBF neural network and the classification discriminant analysis function (Classify) in MATLAB, the proposed SA-PNN has higher accuracy, sensitivity and specificity for discriminating lung cancer and the adjacent normal tissues based on permittivity.

Economic analysis of the risk of replacing corn grains (Zea mays) with pearl millet grains (Pennisetum glaucum) in the diet of feedlot cattle / Análise econômica do risco da substituição de grãos de milho (Zea mays) por grãos de milheto (Pennisetum glaucum) na dieta de bovinos confinados

ABSTRACT: The goal of the present study was to assess the economic viability relating to the risk of replacing corn with pearl millet in diets with 80% concentration for feedlot cattle confined for 89 days. Replacement levels were: 0, 33, 66, and 100%. The risk was estimated using Monte Carlo simulation, Spearman's rank correlation test between input variables, stochastic dominance, and analysis of sensitivity. The expected average values ± standard deviation for net present value (R$/animal) were ± 71.74 ± 283.32, 91.23 ± 285.18, 196.05 ± 273.79, and 223.80 ± 267.96 for diets containing 0, 33, 66, and 100% of pearl millet, respectively. The probability of ≥0 net present value was 63.4, 66.1, 78.4, and 82.4%, respectively. The net present values were statistically different (P<0.05), and the higher levels dominated the lower values. The items that most influenced the net present values were, in descending order, prices of unfinished and finished cattle, initial and final weights, prices of concentrate and forage, concentrate and forage consumption. Based on the results of the simulation, diet of 100% pearl millet exhibited the best economic viability.

RESUMO: O objetivo do estudo foi avaliar a viabilidade econômica relacionada ao risco da substituição de milho por milheto em dietas com 80% de concentrado no confinamento de bovinos por 89 dias. Os níveis de substituição foram: 0, 33, 66 e 100%. O risco foi estimado usando simulação de Monte Carlo, correlação de Spearman entre as variáveis ​​de entrada, dominância estocástica e análise de sensibilidade. Os valores médios esperados ± desvio padrão para o valor presente líquido (R$/animal) foram de ± 71,74 ± 283,32, 91,23 ± 285,18, 196,05 ± 273,79 e 223,80 ± 267,96 para dietas contendo 0, 33, 66 e 100% de milheto, respectivamente. A probabilidade de valor presente líquido ≥0 foi de 63,4, 66,1, 78,4 e 82,4%, respectivamente. Os valores presentes líquidos foram estatisticamente diferentes (p<0,05), e os níveis mais elevados dominaram os valores mais baixos. Os itens que mais influenciaram os valores presentes líquidos foram, em ordem decrescente, os preços de bovinos não terminados e acabados, pesos inicial e final, preços de concentrado e forragem, consumo de concentrado e forragem. Com base nos resultados da simulação, a dieta de 100% de milheto mostrou a melhor viabilidade econômica.

Aplicación de modelos paramétricos alternativos para el análisis de supervivencia de pacientes con cáncer / Application of alternative parametric models for the survival analysis of cancer patients

RESUMEN En el presente artículo se describe una metodología que permite tener un acercamiento a modelos probabilísticos alternativos para el análisis de supervivencia, con censura por la derecha, distintos a los que usualmente se estudian (distribución: exponencial, gamma, Weibull y log-normal), ya que es posible que los datos no se ajusten siempre con suficiente precisión por las distribuciones existentes. La metodología utilizada permite mayor flexibilidad de modelar observaciones extremas, ubicadas generalmente en la cola derecha de la distribución de los datos, lo cual admite que algunos eventos aún tengan la probabilidad de ocurrir, lo que no sucede con los modelos tradicionales y el estimador de Kaplan-Meier, el cual estima para los tiempos más prolongados, probabilidades de supervivencia aproximadamente iguales a cero. Para mostrar la utilidad de la propuesta metodológica, se consideró una aplicación con datos reales que relaciona tiempos de supervivencia de pacientes con cáncer de colon.

ABSTRACT This article describes a methodology that allows an approach to alternative right-censored probabilistic models for the analysis of survival, different to those usually studied (exponential, gamma, Weibull, and log-normal distribution) since it is possible that the data do not always fit with sufficient precision due to existing distributions. The methodology used allows for greater flexibility when modeling extreme observations, generally located in the right tail of data distribution, which admits that some events still have the probability of occurring, which is not the case with traditional models and the Kaplan-Meier estimator, which estimates for the longest times, survival probabilities approximately equal to zero. To show the usefulness of the methodological proposal, we considered an application with real data that relates survival times of patients with colon cancer (CC).

Automatic heart activity diagnosis based on Gram polynomials and probabilistic neural networks

The paper proposes a new approach to heart activity diagnosis based on Gram polynomials and probabilistic neural networks (PNN). Heart disease recognition is based on the analysis of phonocardiogram (PCG) digital sequences. The PNN provides a powerful tool for proper classification of the input data set. The novelty of the proposed approach lies in a powerful feature extraction based on Gram polynomials and the Fourier transform. The proposed system presents good performance obtaining overall sensitivity of 93%, specificity of 91% and accuracy of 94%, using a public database of over 3000 heart beat sound recordings, classified as normal and abnormal heart sounds. Thus, it can be concluded that Gram polynomials and PNN prove to be a very efficient technique using the PCG signal for characterizing heart diseases.

Do different sampling designs produce differences in the metrics of curimba, Prochilodus lineatus (Characiformes: Prochilodontidae)?

Probabilistic sampling, a classical recommendation for unbiased data, has been often overlooked. Fish sampling in reservoirs, unlike most rivers, can be accomplished by a variety of probabilistic sampling designs due to few restrictions in the choice of sampling sites (SSs). We evaluated whether population metrics of Prochilodus lineatus differ between fixed SSs (do not change with each sampling trip) and variable SSs (change with each sampling trip) in the Volta Grande (VGR) and Jaguara (JR) reservoirs of the Grande River, Paraná River basin, Brazil. We used gillnets to sample fish at nine probabilistic fixed SSs and nine probabilistic variable SSs per sampling trip. We conducted 25 sampling trips in VGR and 22 in JR during 2011 to 2015, and performed 35 analyses of 8 metrics for each reservoir. We found sampling design influenced only 7% of the analyses involving three metrics, apparently caused by biased data of fixed SSs. We attribute the small percentage of analyses influenced by sampling design to the low spatial heterogeneity of the reservoirs. The choice of the most appropriate sampling design seems to depend on the type of variation (temporal or spatial) that one wishes to detect, and the availability of time and financial resources.(AU)

A amostragem probabilística, uma recomendação clássica para dados não enviesados, tem sido frequentemente negligenciada. Reservatórios, diferentemente da maioria dos rios, permitem diversos desenhos amostrais probabilísticos para a amostragem de peixes por impor poucas restrições na escolha de pontos de coletas. Neste trabalho, avaliamos se métricas populacionais do Prochilodus lineatus diferem entre amostras de pontos fixos (não mudam a cada campanha) ou variáveis (mudam a cada campanha) nos reservatórios de Volta Grande (VGR) e Jaguara (JR), rio Grande, bacia do alto rio Paraná, Brasil. Amostramos os peixes com redes de emalhar em nove pontos fixos e nove pontos variáveis por campanha, todos probabilísticos. Foram 25 campanhas em RVG e 22 em RJ de 2011 a 2015. Para cada reservatório, fizemos 35 análises para 8 métricas. Encontramos influência do desenho amostral em apenas 7% das análises e em três métricas, aparentemente provocada por dados enviesados dos pontos fixos. Atribuímos a pequena porcentagem de análises influenciada pelo desenho amostral à baixa heterogeneidade espacial dos reservatórios. A escolha do desenho amostral mais apropriado parece depender, além disso, do tipo de variação (temporal ou espacial) que se deseja detectar, e a disponibilidade de tempo e de recurso financeiro.(AU)

Risk analysis of the economic viability of feedlot aberdeen angus steers fed with different proportions of concentrate / Análise de risco da viabilidade econômica do confinamento de novilhos aberdeen angus alimentados com diferentes proporções de concentrado

The economic viability of feedlot Aberdeen Angus steers fed with diets composed of different concentrate levels (CL) in dry matter (25, 40, 55 or 70%) was estimated using Monte Carlo simulation combined with Spearman rank correlation, considering nine random input variables, as well as stochastic dominance (DOM) and sensitivity (SENS) analyses. For the financial indicator simulation, net present value (NPV), cash flow with indicators of performance, and the probability distribution of all cost and income items (from 2003 to 2014) were used. Latin hypercube sampling and a Mersenne Twister random number generator was employed for the simulation, which included 2000 interactions. The expected mean values ± standard deviation for NPV (USD/animal) were 44.94 ± 68.01, 44.50 ± 69.25, 15.39 ± 69.22 and 54.20 ± 71.58 for the diets containing 25, 40, 55 and 70% CL, respectively. The probability of NPV 0 was 76.8, 76.0, 57.9 and 78.1%, respectively, from the smallest to largest CL. The DOM analysis showed that 25 and 40% CL have similar probability curves, the 70% level dominated the remaining and all CL dominated 55%. According to SENS analysis, the items that most influenced the NPV were, in decreasing order, finished and feeder cattle price, initial and final weights, concentrate and roughage price, concentrate intake, minimum rate of attractiveness and roughage intake. Based on the simulation results, the 70% CL showed a higher NPV and greater likelihood of economic viability. The probabilistic simulation technique is an interesting tool for decision-making in investment projects with beef cattle feedlot, therefore, further studies in this line of research is recommended.

Estimou-se o risco da viabilidade econômica do confinamento de novilhos Aberdeen Angus alimentados com dietas com diferentes níveis de concentrado (NC) na matéria seca (25, 40, 55 ou 70%), utilizando simulação de Monte Carlo associado com o uso de correlação de Spearman entre nove variáveis aleatórias de entrada, dominância estocástica (DOM) e análise de sensibilidade (SENS). Para a simulação do indicador financeiro Valor Presente Líquido (VPL), foi utilizado fluxo de caixa com indicadores de desempenho e distribuição de probabilidade de todos os itens de custos e receitas (anos de 2003 a 2014). Amostragem de Hipercubo Latino e gerador de números aleatórios Mersenne Twister foram utilizados para a simulação com 2.000 interações. Os valores médios esperados para VPL ± desvio padrão (USD/animal) foram de: 44,94 ± 68,01; 44,50 ± 69,25; 15,39 ± 69,22 e 54,20 ± 71,58, respectivamente, para 25, 40, 55 e 70% NC. As probabilidades do VPL 0 foram 76,8%; 76,0%; 57,9% e 78,1%, respectivamente, do menor para maior NC. A análise de DOM demonstrou que 25 e 40% de concentrado apresentam curvas de probabilidade similares; 70% dominou os demais e 55% foi dominado por todos os NC. De acordo com a SENS, os itens que mais influenciaram no VPL foram, em ordem decrescente, os preços do boi gordo e magro, os pesos final e inicial, preços do concentrado e do volumoso, consumo de concentrado, taxa mínima de atratividade e consumo de volumoso. Com base nos resultados de simulação, o NC de 70% apresentou maior VPL e maior probabilidade de viabilidade econômica. A técnica de simulação probabilística demonstrou ser interessante ferramenta para tomada de decisões em projetos de investimento com confinamento de bovinos de corte, sugerindo a expansão de estudos nesta linha de pesquisa.

Stochastic simulation of the economic viability of feedlot steers fed with different proportions of concentrate / Simulação estocástica da viabilidade econômica do confinamento de novilhos alimentados com diferentes proporções de concentrado

The economic viability of feedlot zebu bulls, slaughtered at 450 kg after 90 days of feeding with diets consisting of different proportions of concentrate in dry matter (40, 60 or 80%), was estimated using Monte Carlo simulations, with or without the inclusion of Spearman rank correlations among random input variables, stochastic dominance (DOM) and sensitivity analysis (SENS). The roughage used was chopped sugar cane. Cash flow with indicators of performance, and probability distributions of all items of cost and revenue (from 2003 to 2014), were used to stimulate net present value (NPV), the financial indicator. Latin hypercube sampling and a Mersenne Twister random number generator were employed for the simulation with 2000 interactions. The risk was found to be more accurately estimated when correlations between random input variables were included (probability of NPV 0 ± standard deviation was 35 ± 166.05% and 31 ± 139.75% for the simulation without and with correlation, respectively). Considering this result, DOM and SENS were only carried out including these correlations. The expected value for NPV was similar between the different levels of concentrate (average USD -62/animal and NPV 0 of 33%) according to DOM analysis of simulations including correlations. From the SENS analysis, the final weight, finished cattle price, feeder cattle price and initial weight were the items with the greatest influence on NPV, regardless of the level of concentrate used, followed by intake and the cost-related items of diet and minimum rate of attractiveness. Based on the results obtained by simulation, the direct benefit of feedlot could be classified as high risk, suggesting the increased use of Monte Carlo simulation for decision-making.

Estimou-se o risco da viabilidade econômica do confinamento de bovinos zebuínos abatidos com 450 kg após 90 dias de alimentação, com dietas com diferentes proporções de concentrado na matéria seca (40, 60 ou 80%), utilizando simulação de Monte Carlo associado ou não com o uso de correlação de Spearman entre as variáveis aleatórias de entrada, dominância estocástica (DOM) e análise de sensibilidade (SENS). O volumoso utilizado foi cana-deaçúcar picada. Para a simulação do indicador financeiro Valor Presente Líquido (VPL), foi utilizado fluxo de caixa com indicadores de desempenho e distribuição de probabilidade de todos os itens de custos e receitas (anos de 2003 a 2014). Amostragem de Hipercubo Latino e gerador de números aleatórios Mersenne Twister foram utilizados para a simulação com 2.000 interações. O risco foi estimado com maior precisão incluindo correlações entre variáveis aleatórias de entrada (probabilidades de VPL 0 ± desvio padrão foram 35 ± 166,05% and 31 ± 139,75% para a simulação com e sem correlação, respectivamente). A partir deste resultado, DOM e SENS foram realizadas apenas com correlação entre variáveis aleatórias de entrada. O valor esperado para VPL foi semelhante entre os diferentes níveis de concentrado (média de USD -62 / animal e VPL 0 de 33%), de acordo com a análise de DOM das simulações com correlação. Na SENS, independentemente do nível de concentrado usado, o peso final, os preços do boi gordo e magro e peso inicial foram os itens mais importantes a influenciar o VPL, seguido de consumo da dieta, preços da dieta e taxa mínima de atratividade. Com base nos resultados de simulação, poderia ser classificado o benefício direto de confinamento como de alto risco, sugerindo a expansão dos estudos com uso da técnica de simulação de Monte Carlo na tomada de decisões.

Predicting Recurrence in Cervical Cancer Patients Using Clinical Feature Analysis.

The paper demonstrates an analytic approach for prediction of recurrence in the cervical cancer patients using a probabilistic model. The techniques used for classification and prediction are based on recognizing typical and diagnostically most important test features relating to cervical cancer. The main contributions of the research involve predicting the probability of recurrences in no recurrence (First time detection) cases. The conventional statistical and machine learning tools are applied for the analysis. The experimental study demonstrates the feasibility and promising the proposed approach for the said cause with real data.

Pruebas bioquímicas tradicionales y de alta resolución para identificación manual de enterobacterias / Traditional and high-resolution biochemical tests for manual identification of enterobacteria / Provas bioquimicas tradicionais e de alta resolução para identificação manual de enterobacterias

Se comparó una serie tradicional de pruebas bioquímicas con una de alta resolución para identificar 500 cepas de enterobacterias utilizando un método probabilístico para interpretar los resultados. La serie tradicional estuvo formada por 10 pruebas (producción de ornitina descarboxilasa, lisina descarboxilasa, lisina desaminasa, ácido sulfhídrico, indol y gas, hidrólisis de urea, utilización de citrato y de malonato, y movilidad). La serie de alta resolución, también con 10 pruebas, se integró con las primeras 4 mencionadas en la serie tradicional y 6 de fermentación de hidratos de carbono (adonitol, L-arabinosa, celobiosa, L-ramnosa, rafinosa y sorbitol). Con la serie de alta resolución se asignaron identidades únicas a 445 cepas (351 con probabilidad de 1,0 y 94 con probabilidades entre 0,010 y 0,999), y de las restantes 55 cepas, a 53 y 2 se asignaron dos y tres identidades probables respectivamente. Con la serie tradicional se asignaron identidades únicas a 306 cepas (110 con probabilidad de 1,0 y 196 con probabilidades entre 0,001 y 0,999) y a 179 y 5 se asignaron dos y tres identidades probables respectivamente. Diez cepas no se pudieron identificar. Todos los indicadores analizados revelaron la superioridad de la serie de alta resolución. El método probabilístico permitió la comparación objetiva de ambas series.

A traditional series of biochemical tests-was compared to a high-resolution one in order to identify 500 strains of enterobacteria, using a probabilistic method for the interpretation of experimental results. The traditional series was formed by 10 tests (ornithine decarboxylase, lysine decarboxylase, lysine deaminase, sulfhydric acid, indol and gas production, urea hydrolysis, citrate and malonate utilization, and motility). The high-resolution one was also formed by 10 tests, including the first 4 tests mentioned above and 6 carbohydrate fermentation tests (adonitol, L-arabinose, cellobiose, L-rhamnose, raffinose, and sorbitol). With the high-resolution series, single identities were assigned to 445 strains (351 with a probability of 1.0 and 94 with probabilities in the range 0.010-0.999), and for the remaining strains two and three probable identities were assigned to 53 and 2 strains, respectively. With the traditional series, single identities were assigned to 306 strains (110 with a probability of 1.0 and 196 with probabilities in the 0.001-0.999 range), two and three probable identities were assigned to 179 and 5 strains respectively; 10 strains turned out to be non-identifiable. Every parameter of comparison used revealed the superiority of the high-resolution series. The probabilistic method for interpretation of experimental results allowed an objective comparison of both series.

Foi comparada uma série tradicional de testes bioquímicos com uma outra de alta resolução para identificar 500 cepas de enterobactérias usando uma abordagem probabilística para a interpretação dos resultados. A série tradicional consistiu em 10 testes (produção de ornitina descarboxilase, lisina descarboxilase, lisina desaminase, ácido sulfídrico, indol e gás, hidrólise da ureia, utilização de citrato e de malonato, e mobilidade). A série de alta resolução, também com 10 ensaios, integrou-se com as primeiras 4 mencionadas na série tradicional e 6 de fermentação de hidratos de carbono (adonitol, L-arabinose, celobiose, L-ramnose, rafinose e sorbitol). Com a série de alta resolução foram atribuídas identidades únicas a 445 cepas (351, com probabilidade 1,0, e 94, com probabilidade entre 0,010 e 0,999), e das restantes 55 cepas, a 53 e 2 foram atribuídas duas e três identidades possíveis, respectivamente. Com a série tradicional foram atribuídas identidades únicas a 306 cepas (110 com probabilidade de 1,0 e 196 com probabilidades entre 0,001 e 0,999) e a 179 e 5 foram atribuídas duas e três identidades prováveis, respectivamente. Dez cepas não puderam ser identificadas. Todos os indicadores analisados demonstraram a superioridade da série de alta resolução. O método probabilístico permitiu a comparação objetiva de ambas as séries.

Risk of symptomatic dengue for foreign visitors to the 2014 FIFA World Cup in Brazil

Brazil will host the FIFA World Cup™, the biggest single-event competition in the world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated 600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the 2014 event are theoretically at risk for dengue. We calculated the risk of dengue acquisition to non-immune international travellers to Brazil, depending on the football match schedules, considering locations and dates of such matches for June and July 2014. We estimated the average per-capita risk and expected number of dengue cases for each host-city and each game schedule chosen based on reported dengue cases to the Brazilian Ministry of Health for the period between 2010-2013. On the average, the expected number of cases among the 600,000 foreigner tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not only benefit individual travellers for adequate pre-travel preparations, but also provide valuable information for public health professionals and policy makers worldwide. Furthermore, estimates of dengue cases in international travellers during the World Cup can help to anticipate the theoretical risk for exportation of dengue into currently non-infected areas.

Dietary Habits and Exposure to Pesticides in Dutch Infants.

Background: Children are known to have higher dietary exposure levels to pesticide residues than adults due to higher consumption levels per kilogram bodyweight. Also social concern exists on the effects of these residues in young children, who are growing rapidly. To assess whether a certain compound may pose a risk for young children, it is important to have consumption levels of the foods that may contain the compound of interest in this age group. In the Netherlands food consumption data are available of children from 1 year onwards. However, the majority of children (if not all) already consume solid foods before age 1. Aims: Performance of a food consumption survey among Dutch infants aged 8 - 12 months gathering data on food consumption levels, and measuring and estimating the dietary exposure to selected pesticide residues Approach: Food consumption data were collected using a 1-daydietary record method. Weighing scales were provided, so that the amount consumed could be quantified accurately. During the study also duplicate portions of all the foods consumed by the children during the study day were collected. These duplicate portions were analysed for 19pesticides at the RIKILT - Institute of Food Safety to estimate the real intake of pesticides. Results: In total 373 infants (186 girls and 187 boys) were included. The fruit most eaten by this age group was banana (58%), followed by apple (34%), pear (28%) and kiwi (20%). Carrot (18%) was the most favorite vegetable, followed by broccoli (9%) and green beans (8%). Potato was also consumed frequently (49%). Of all the fruits and vegetables consumed by the children large portion sizes (LPs) were calculated at the level of the raw agricultural commodity. These LPs can be used in the point estimate approach to assess the acute dietary intake of toxic pesticide residues in the field of pesticide regulation. The infant food consumption database can also be used for probabilistic modelling of acute dietary exposure. Of 250 infants the duplicate portions were analysed for 19 pesticides. Of these samples a significant percentage (11%) had a low exposure to one or more pesticides. None of the exposures exceeded the toxicological reference level (acceptable daily intake (ADI) or acute reference dose (ARfD)). Conclusion: This study among infants resulted in a first impression of actual intake levels of pesticide residues by this age group in the Netherlands via the diet, an estimate of the LPs of fruits and vegetables consumed by young children for use in the point estimate approach and a database with consumption levels useful for probabilistic exposure assessments. Furthermore the duplicate portions collected can be used for the analysis of other compounds that may affect the development of young growing children (e.g. deoxynivalenol (DON), acrylamide, heavy metals). The complete report can be downloaded for free from http://edepot.wur.nl/44408. Full report is also available as ‘Supplementary File’.

Neuropsychological study of feedback learning in patients with schizophrenia / 中华行为医学与脑科学杂志

Objective To explore the pattern of feedback learning deficits in patients with schizophrenia.Methods Twenty-five patients with schizophrenia and 31 controls participated in the study of probabilistic stimulus selection task.The percentage of choose A and avoid B and individual training blocks of reach performance criterion were analyzed.Results There was no significant difference on the percentage ofchoose A between patient group and control group(control group:(66.13±26.31) ％ ; patient group:(63.75±20.57) ％ ; t=0.37,P=0.713).The percentage of avoid B in patient group was significantly lower than that in control group(control group:(62.10±27.10)％;patient group:(49.75±13.68)％; t=2.212,P=0.032).In addition,the training blocks of reach performance criterion in patient group was significantly greater than that in control group (control group:3.23±2.012;patient group:4.64±1.977; t=-2.635,P=0.011).Conclusion The deficits of feedback learning in patients with schizophrenia is largely due to the failure of avoiding negative feedback stimuli.Learning efficiency was lower in patients with schizophrenia than controls.

Validación del euroSCORE en la valoración del riesgo quirúrgico en un centro de referencia cardiovascular en Colombia / Validation of the EuroSCORE in assessing surgical risk in a Cardiovascular referral center in Colombia

Introducción y objetivos: El euroSCORE es el modelo predictivo de mortalidad en cirugía cardiovascular de mayor aceptación en todo el mundo. El objetivo del presente estudio fue validar estadísticamente este modelo tanto en sus variantes logística como aditiva, en un centro de referencia para cirugía cardiovascular en Colombia. Métodos: Estudio retrospectivo; se incluyeron a los pacientes de cirugía cardiaca mayor intervenidos durante los años 2007 a 2009 en el centro. Se determinó para cada paciente el riesgo de muerte tanto con el euroSCORE aditivo como con el logístico; se validó a partir de su capacidad de calibración y discriminación para comparar la mortalidad predicha con la observada, de manera global y para cada grupo de riesgo. Resultados: Se incluyeron 498 pacientes, 226 (45%) correspondientes a cirugía de revascularización miocárdica aislada y el resto a otras cirugías cardiovasculares mayores. La calibración del modelo fue de p = 0.8 para el aditivo y de 0.2 para el logístico. Las áreas bajo la curva receiver operating characteristic fueron de 0.85 para ambos modelos. La mortalidad global observada alcanzó el 7.03% mientras que la estimada fue 5.34% por el modelo logístico y 4.47% con el aditivo. Conclusiones: La predicción fue buena con los dos modelos, tanto de manera global como dentro de cada categoría de riesgo; el modelo logístico fue el más aproximado a la mortalidad observada. El euroSCORE ha sido validado satisfactoriamente en este centro de referencia en Colombia y los resultados permiten calificar bien el desempeño del programa de cirugía cardiovascular en este centro.

Introduction and objectives: The euroSCORE is the predictive model of mortality in cardiovascular surgery more accepted worldwide. The objective of the present study was to statistically validate this model in both its logistic and additive variants in a cardiovascular referral center in Colombia. Methods: We included patients undergoing major cardiac surgery consecutively during the period of years 2007 and 2009 in the center. The risk of death was determined separately for each patient for both the additive euroSCORE and the logistic model. The capacity calibration of the model and its discrimination were calculated by comparing the observed with the predicted mortality, both overall and for each risk group. Results: Were included 498 patients, 226 (45%) of isolated CABG, and the rest other major cardiovascular surgical procedures. The calibration of the model was satisfactory (p = 0.8 and 0.2 additive and logistic). The discrimination was calculated with an area under the curve AUC of 0.85 for both models. The overall mortality reached 7.03% while 5.34% was estimated by the logistic model, and 4.47% with the additive one. The prediction was good with the two models both for overall and within each risk category, but it was more accurate in the logistic model. Conclusions: The euroSCORE has been successfully validated in this cardiovascular referral center. The results allow us to properly qualify the performance of this cardiovascular surgery program of Colombia.