Self-modeling ordinal regression with time invariant covariates - An application to prostate cancer data.

In a prostate cancer study, the severity of genito-urinary (bladder) toxicity is assessed for patients who were given different doses of radiation. The ordinal responses (severity of side effects) are recorded longitudinally along with the cancer stage of a patient. Differences among the patients due to time-invariant covariates are captured by the parameters.

Asymptotic behavior of the scaled mutation rate estimators.

Important aspects of population evolution have been investigated using nucleotide sequences. Under the neutral Wright-Fisher model, the scaled mutation rate represents twice the average number of new mutations per generations and it is one of the key parameters in population genetics. In this study, we present various methods of estimation of this parameter, analytical studies of their asymptotic behavior as well as comparisons of the distribution's behavior of these estimators through simulations.

Network analysis reveals contrasting effects of intraspecific competition on individual vs. population diets.

Optimal foraging theory predicts that individuals should become more opportunistic when intraspecific competition is high and preferred resources are scarce. This density-dependent diet shift should result in increased diet breadth for individuals as they add previously unused prey to their repertoire. As a result, the niche breadth of the population as a whole should increase.

Build-up mechanisms determining the topology of mutualistic networks.

The frequency distribution of the number of interactions per species (i.e., degree distribution) within plant-animal mutualistic assemblages often decays as a power-law with an exponential truncation.

[Prevalence of cardiovascular risk factors in child and adolescent students in the city of Maceió].

Objective: To determine the prevalence of systemic arterial hypertension (SAH), "risk of overweight," overweight, sedentary lifestyle, and smoking in children and adolescents from 7 to 17 years of age, of both sexes, in public and private schools in the city of Marceió, in the state of Alagoas.

Methods: A cross-sectional epidemiological study with sampling from a population pool was carried out. It comprised elementary and middle schools, randomly selected.