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A spatial survival analysis was performed to identify some of the factors that influence the survival of patients with COVID-19 in the states of Guerrero, México, and Chihuahua. The data that we analyzed correspond to the period from 28 February 2020 to 24 November 2021. A Cox proportional hazards frailty model and a Cox proportional hazards model were fitted. For both models, the estimation of the parameters was carried out using the Bayesian approach. According to the DIC, WAIC, and LPML criteria, the spatial model was better. The analysis showed that the spatial effect influences the survival times of patients with COVID-19. The spatial survival analysis also revealed that age, gender, and the presence of comorbidities, which vary between states, and the development of pneumonia increase the risk of death from COVID-19. [ABSTRACT FROM AUTHOR]

Objective: To evaluate three proportions of alcohol in traps with one and three windows and two different colors to capture Hypothenemus hampei Ferrari in Coffea arabica L. plants. Design/methodology/approach: The experiment followed a completely randomized design with a complete factorial arrangement and four replications. From March to July 2007, three mixtures of ethyl: methyl alcohol were evaluated in different proportions (1: 0, 0: 1 and 1: 1). In addition, green and transparent traps were used, designed with a single or three windows. The number of captured coffee berry borers, water loss, attractant evaporation and damaged fruits percentage was evaluated. The data were analyzed through an analysis of variance and a test of means differences (Tukey, p ≤ 0.05). Results: The mixture of ethyl: methyl alcohol 1: 1 was the best, with an average catch of 980 trapped - insects week-1. The single window of transparent color traps was the most efficient to avoid water loss, with an average loss of 1,129.79 mL and 905 mL respectively. Limitations on study/implications: The design and color of the traps did not influence the capture efficiency and the evaporation of the attractant during the evaluated months. Therefore, it should be further evaluated during other important phenological stages for the crop. Findings/conclusions: Transparent color traps with a window and 1: 1 ethyl: methyl alcohol were efficient for capturing H. hampei and lowering their population. [ABSTRACT FROM AUTHOR]

In this work, a simulation study is conducted to evaluate the performance of Bayesian estimators for the log–linear exponential regression model under different levels of censoring and degrees of collinearity for two covariates. The diffuse normal, independent Student-t and multivariate Student-t distributions are considered as prior distributions and to draw from the posterior distributions, the Metropolis algorithm is implemented. Also, the results are compared with the maximum likelihood estimators in terms of the mean squared error, coverages and length of the credibility and confidence intervals. [ABSTRACT FROM PUBLISHER]