The generalized log-gamma mixture model with covariates: local influence and residual analysis

In a sample of censored survival times, the presence of an immune proportion of individuals who are not subject to death, failure or relapse, may be indicated by a relatively high number of individuals with large censored survival times. In this paper the generalized log-gamma model is modified for the possibility that long-term survivors may be present in the data. The model attempts to separately estimate the effects of covariates on the surviving fraction, that is, the proportion of the population for which the event never occurs. The logistic function is used for the regression model of the surviving fraction. Inference for the model parameters is considered via maximum likelihood. Some influence methods, such as the local influence and total local influence of an individual are derived, analyzed and discussed. Finally, a data set from the medical area is analyzed under the log-gamma generalized mixture model. A residual analysis is performed in order to select an appropriate model

Bias-corrected Pearson estimating functions for Taylor`s power law applied to benthic macrofauna data

Estimation of Taylor`s power law for species abundance data may be performed by linear regression of the log empirical variances on the log means, but this method suffers from a problem of bias for sparse data. We show that the bias may be reduced by using a bias-corrected Pearson estimating function. Furthermore, we investigate a more general regression model allowing for site-specific covariates. This method may be efficiently implemented using a Newton scoring algorithm, with standard errors calculated from the inverse Godambe information matrix. The method is applied to a set of biomass data for benthic macrofauna from two Danish estuaries. (C) 2011 Elsevier B.V. All rights reserved.FAPESPCNPq (Brazil)Danish Natural Science Research Counci

Efficacy of banana plantlet production by micropropagation

A produção de mudas de bananeira (Musa spp.) através de cultura de tecidos está se tomando uma prática comum em diversas regiões do mundo. No entanto, a ocorrência de variação sornaclonal tem sido um dos principais problemas na utilização deste tipo de material em grande escala. Uma das possíveis causas da ocorrência da variação somaclonal seria o tempo em que o material permanece na cultura in vitro, isto é, o número de subcultivos. Com o objetivo de se determinar qual o potencial de produção de mudas a partir do cultivo de ápices meristemáticos e o comportamento de diferentes clones in vitro, realizouse a cultura de nove ápices meristemáticos, extraídos de rizomas, coletados no campo, da variedade Nanicão, em meio MS suplementado com 4,5 mg/L de BAP, por seis subcultivos, em intervalos de 4 semanas. As avaliações foram feitas em cada subcultura, pela contagem do número de mudas produzidas. Pôdese verificar que os clones se comportam de maneira diferente no cultivo in vitro, existindo ciones que apresentam alta taxa de produção de mudas e ciones que produzem uma quantidade bastante baixa de mudas, embora todo o material tenha sido tratado de maneira homogênea. A produção média de mudas foi de 676 plantas por ápice meristemático em seis subcultivos, tendose obtido 1.850 mudas no clone mais produtivo e 143 mudas no clone menos produtivo. Estes dados podem ser úteis para as empresas, no momento de selecionarem os meristemas mais promissores no início da cultura, e nos cálculos econômicos do preço de cada muda individualmente.The use of banana (Musa spp.) plant production by tissue culture is increasing throughout the world. However the occurrence of somaclonal variation has been one of the most important problems affecting the commercial value of the plants. A reason for the somaclonal variation can be the time of permanence of the culture in vitro, i.e., the number of subcultures. With the aim of evaluating the effectiveness of banana plant production from shoot tip in vitro, and the behavior of vegetative apices coming from different rhizomes of cv. Nanicio, nine shoot tips were cultured in MS medium supplemented with 4.5 mg/L BAP for six subcultures at fourweek intervals. The evaluations were done at each subculture by counting the number of new shoots produced. The results show that shoot tips coming from different rhizomes behave differently under in vitro conditions, some being highly productive and others producing a much smaller number of plants under similar culture conditions. The average number of plants produced was 676 per shoot tip after six subcultures, with 1,850 plants produced by the most productive, against 143 plants produced by the lowest productive one. These data can be very useful for micropropagation companies in the screening of the most promissor shoot tips in the beginning of the culture and in the economic calculations of the individual plantlets prices

Intraguild predation Influences oviposition behavior of blow flies (diptera: Calliphoridae)

The objective of the present study was to determine whether blow flies (Diptera: Calliphoridae) are able to identify larvae of an intraguild predator species in the substrate and avoid laying eggs there. Blow flies oviposited in traps with different treatments: substrate only and substrate with larvae of Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), or Chrysomya putoria (Wiedemann, 1830). Ch. megacephala, Ch. putoria, and Lucilia eximia (Wiedemann, 1819) avoided laying eggs in the trap containing Ch. albiceps larvae. Cochliomyia macellaria (Fabricius, 1775) did not oviposit differently in each substrate but had overall low abundance. The prevalence of species on corpses may be influenced by the ability of the species to detect the presence of other species, mainly predators. In this sense, intraguild predation may result in misinterpretations of a crime scene and should be considered when assessing the minimum postmortem interval115520972102FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2012/02027-0; 2014/03310-3; 2006/55075-

Novel sources of witches` broom resistance (causal agent Moniliophthora perniciosa) from natural populations of Theobroma cacao from the Brazilian Amazon

Witches` broom is a severe disease of Theobroma cacao L. (cacao), caused by the basidiomycete Moniliophthora perniciosa. The use of resistant cultivars is the ultimate method of control, but there are limited sources of resistance. Further, resistance from the most widely used source (`Scavina 6`) has been overcome after a few years of deployment. New sources of resistance have been intensively searched for in the Amazon basin. Here, we evaluated for witches` broom resistance, cacao accessions from various natural cacao populations originally collected in the Brazilian Amazon. Resistance of 43 families was evaluated under nursery and/or field conditions by artificial or natural infection, respectively, based on disease incidence. Screening for resistance by artificial inoculation under nursery conditions appeared to be efficient in identifying these novel resistance sources, confirmed by natural field evaluation over a nine-year period. The increase in natural field infection of `Scavina 6` was clearly demonstrated. Among the evaluated families with the least witches` broom incidence, there were accessions originally collected from distinct river basins, including the Jamari river (`CAB 0371`; `CAB 0388`; `CAB 0392`; and `CAB 0410`); Acre (`CAB 0169`); Javari (`CAB 0352`); Solimes (`CAB 0270`); and from the Purus river basin, the two most outstanding resistant accessions, `CAB 0208` and `CAB 0214`. The large genetic diversity found in cacao populations occurring at river basins from Acre and Amazonas states, Brazil, increased the chance that the selected resistant accessions would be genetically more dissimilar, and represent distinct sources of resistance to M. perniciosa from `Scavina 6`.CEPLACMinistry of AgricultureAmerican Cocoa Research InstituteMinistry of Science and Technology[PP-G7]CNP