A stepwise Bayesian estimator for the total number of distinct species in finite populations: sampling by elements

A stepwise Bayesian estimator for the total number of distinct species in the region of investigation is constructed when sampling by elements is used to collect the sample of species. The species in the region are supposed to be divided into two groups: the first containing those species the researcher believes are present in the region and the second group containing the species in the region which are completely unknown to the researcher. The abundance values of the second group are supposed to follow a Dirichlet distribution. Under this model, the obtained stepwise Bayesian estimator is an extension of that proposed by Lewins & Joanes (1984). When the negative binomial distribution is chosen as a prior distribution for the true value T of species in the region, the stepwise estimator takes a simple form. It is then shown that the estimator proposed by Hill (1979) is a particular case and that the stepwise Bayesian estimator can also be similar to the estimator proposed by Mingoti (1999) for quadrat sampling. Some results of a simulation study are presented as well as one application using abundance data and another in the estimation of population size when capture and recapture methods are used.     

Analysis of ergonomic furniture made of wood and sub-products from renewable forests

The furniture ergonomic evaluation was carried out through the use of questionnaires and forms in industries. For the ergonomic product analysis, it was used the methodology "Object Ergonomics - Ergonomic System Technical Reading" (design goals and management actions), and measurements of products. The values achieved were compared with the standard dimensions, and the compliance or non-compliance of the furniture to it was assessed. In relation to the dimensions of the bed, the following variables did not comply with the norms: external and internal length, external and internal width, height and width of the sidebar and distance to the floor. The dimensions of these variables were above the recommended values. The double bed was inadequate for management actions and maintenance. Since the kitchen cabinet is a product that went through physical testing and follows national standards; the finish used is powder coating. The kitchen cabinet proved to be appropriate in all design requirements and for management actions. Both furniture pieces were inadequate, considering the difficulty for maintenance when a product or part of it was damaged. It was recommended the creation of regulatory standards for the production of safe and comfortable furniture.     

Sleep patterns and sleepiness of working college students

The double journey (work and study) may result or aggravate health problems, including sleep disturbances, as observed in previous studies with high school students. The aim of this study is to analyze the sleep-wake cycle and perceived sleepiness of working college students during weekdays. Twenty-three healthy college male students, 21-24 years old, working during the day and attending classes in the evening, participated in this study. During five consecutive days, the students filled out daily activities logs and wore actigraphs. Mean sleeping time was lower than 6 hours per night. No significant differences were observed in the sleep-wake cycle during the weekdays. The observed lack of changes in the sleepwake cycle of these college students might occur as participants were not on a free schedule, but exposed to social constraints, as was the regular attendance to evening college and day work activities. Sleepiness worsened over the evening school hours. Those results show the burden carried by College students who perform double activities - work and study.     

Quality of diet of working college students

Considering the scarcity of studies with young workers and the role of diet in the prevention of chronic diseases, the objective of the study was to assess the quality of diet of working college students. The present study investigated 43 university students, aged between 18 and 25 years old who had systematically being involved in a working activity in the past 6 months, paid or unpaid, at least 6 hours daily, five days a week. Dietary intake measured by seven dietary records covering every day of the week was used to calculate the Brazilian Healthy Eating Index Revised (B-HEIR). It was observed a low B-HEIR score (53.43,±7.81) indicating a risk of a poor quality of diet, with high intake of sodium and sugar and low consumption of fruits and whole grains. This poor quality of diet can result in an inadequate nutritional status that may increase the risk of obesity and chronic diseases.     

ERGOBERÇO® (Ergonomics Crib)--evaluation of the prototype for a adaptation to safety's variables and comfort

The crib is the infantile furniture more mentioned in infantile accidents. In spite of the existence of several models, many of them are not appropriate to their users and considered insecure. The objective of this study was to structure the prototype of ERGOBER?O?, considering technical norms and evaluation in loco of the prototype through structured interview answered by the participants of the research. The prototype was evaluated as safer, resistant and comfortable than the crib used by the mothers and participant users of the study. The aspects with larger acceptance index were the movable grating and the compact base, defined for the users as facilitators of the use and attribute of safety of the prototype. Even the prototype having been very appraised and accept for the users, it will be necessary to restructure the prototype so that the same can still be adapted more the users' needs, being, besides insurance and comfortable, with compatible aesthetic pattern with the expectation of these.     

A note on the sample size required in sequential tests for the generalized binomial distribution

In this paper, we discuss the sample size needed to perform Wald's sequential statistical test for the proportion of non-conforming items generated by a process when the results of the inspections are correlated and the generalized binomial distribution proposed by Madsen (1993) is used. It will be shown that, in the presence of correlation, the sample size increases as the value of the coefficient of correlation increases--being much higher for processes with small failure rates.     

Bayesian estimator for the total number of distinct species when quadrat sampling is used

A Bayesian estimator for the total number of distinct species present in the region of investigation is constructed when the quadrat sampling procedure is used to collect a sample of species. The estimator is based on a model similar to that used by Mingoti and Meeden, and uses as a special case the zero truncated negative binomial distribution as a prior distribution for the true number S of distinct species in the region. Confidence intervals are also obtained. Simple comparisons with the first-order jackknife estimator and the empirical Bayesian estimator are performed.