ALTERNATIVE SAMPLING STRATEGY FOR A RANDOM OPTIMIZATION ALGORITHM

Alternative sampling procedures are compared to the pure random search method. It is shown that the efficiency of the algorithm can be improved with respect to the expected number of steps to reach an epsilon-neighborhood of the optimal point.

Sino-aortic denervation causes right atrial beta adrenoceptor down-regulation

Rat isolated right atria obtained 1 wk after sinoaortic denervation were less sensitive to the chronotropic actions of beta-agonists than were tissues obtained from animals that underwent sham surgery or no surgery at all. The potencies, but not the maximal responses for two high efficacy agonists, norepinephrine and isoproterenol, were reduced about 3- to 4-fold. Sinoaortic denervation (SAD) caused about a 3-fold decrease in potency and about a 60% decrease in maximal response for a low efficacy agonist, prenalterol. The changes in the actions of these agonists occurred in the absence of any changes in the subtype of beta receptor mediating the chronotropic response. The results of analyses of the data for prenalterol showed that SAD caused a decrease in the operational efficacy of this agonist without any changes in its K-D value for beta-1 adrenoceptors. SAD had no effect on the responses of the tissue to blockade of uptake 1 and uptake 2, suggesting no compensatory changes in the removal processes caused the decreased potency. The results of radioligand binding assays showed that SAD caused a decrease in the maximal binding of I-125-cyanopindolol without altering its K-D. Also, the results of competition binding assays confirmed the lack of effect of SAD on the K-D for prenalterol. The SAD-induced changes in the actions of agonists acting at right atrial beta-1 receptors were caused by a down-regulation of beta-1 adrenoceptors, which probably occurred in response to SAD-induced increases in sympathetic tone.

VSSI (X)over-bar charts with sampling at fixed times

A standard (X) over bar chart for controlling the process mean takes samples of size no at specified, equally-spaced, fixed-time points. This article proposes a modification of the standard (X) over bar chart that allows one to take additional samples, bigger than no, between these fixed times. The additional samples are taken from the process when there is evidence that the process mean moved from target. Following the notation proposed by Reynolds (1996a) and Costs (1997) we shortly call the proposed (X) over bar chart as VSSIFT (X) over bar chart: where VSSIFT means variable sample size and sampling intervals with fixed times. The (X) over bar chart with the VSSIFT feature is easier to be administered than a standard VSSI (X) over bar chart that is not constrained to sample at the specified fixed times. The performances of the charts in detecting process mean shifts are comparable.

A Top-Down Approach for Distribution Loss Evaluation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Direct and indirect top-down effects of previous contact with an enemy on the feeding behavior of blowfly larvae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of survey methods for sampling anuran species richness in the neotropics.

Species richness is central to ecological theory, with practical applications in conservation, environmental management and monitoring. Several techniques are available for measuring species richness and composition of amphibians in breeding pools, but the relative efficacy of these methods for sampling high-diversity Neotropical amphibian fauna is poorly understood. I evaluated seven studies from south and south-eastern Brazil to compare the relative and combined effectiveness of two methods for measuring species richness at anuran breeding pools: acoustic surveys with visual encounter of adults and dipnet surveys of larvae. I also compared the relative efficacy of each survey method in detecting species with different reproductive modes. Results showed that both survey methods underestimated the number of species when used separately; however, a close approximation of the actual number of species in each breeding pool was obtained when the methods were combined. There was no difference between survey methods in detecting species with different reproductive modes. These results indicate that researchers should employ multiple survey methods that target both adult and larval life history stages in order to accurately assess anuran species richness at breeding pools in the Neotropics.

The carpal pad as an alternative sampling site for blood glucose testing in dogs

To investigate the feasibility and validity of sampling blood from the carpal pad in hospitalised healthy and diabetic dogs. METHODS The carpal pad was compared to the ear as a sampling site in 60 dogs (30 healthy and 30 diabetic dogs). RESULTS Lancing the pads was very well tolerated. The average glucose concentrations in blood samples obtained from the ears and carpal pads exhibited a strong positive correlation (r = 0.938) and there were no significant differences between them (P = 0.914). In addition, 98.3% of the values obtained were clinically acceptable when assessed by the error grid analysis. CLINICAL SIGNIFICANCE The carpal pad is a good alternative sampling site for home monitoring, especially in animals with a soft and/or light-coloured pad.