Pigeons prefer signals for reinforcement that require greater effort (or time) to obtain over those that require less effort to obtain (T. S. Clement, J. Feltus, D. H. Kaiser, & T. R. Zentall, 2000). Preference was attributed to contrast (or to the relatively greater improvement in conditions) produced by the appearance of the signal when it was preceded by greater effort. In Experiment 1, the ...

OBJECTIVE To assess the sensitivity, specificity, and feasibility of a new chemiluminescence immunoassay (CLIA) in the diagnosis of syphilis. METHODS At first, a retrospective study was conducted, using 135 documented cases of syphilis and 30 potentially interfering samples and 80 normal sera. A prospective study was also performed by testing 2, 071 unselected samples for routine screening fo...

Reputable pig breeding programmes have been very successful in reducing production costs over the last twenty years through significant genetic progress in a wide variety of traits including growth, feed conversion, reduced backfat thickness and, over the last decade, litter size and litters per sow per year [1] . However, with some notable exceptions, genetic progress in many meat and eating q...

A field experiment was conducted in the experimental field of Genetics and Plant Breeding Department, Sher-e Bangla Agricultural University, Dhaka, Bangladesh to study variability in 10 F4 lines obtained through intervarietal crosses along with 8 released varieties of Brassica rapa. Significant variation was observed among all the genotypes for all the characters studied. Considering genetic pa...

This document describes the trends in network monitoring technology and the requirements of emerging network monitoring applications, and outlines challenges and potential directions for next generation monitoring systems. We also discuss our experiences in designing the SCAMPI monitoring platform.

BACKGROUND Measurements of aldosterone have become more common since the recognition that primary aldosteronism is a more frequent cause of hypertension than previously believed. Our aim was to compare concentrations reported by 4 assays for samples obtained after saline infusion during dynamic testing. METHODS We tested 104 participants (27 with primary aldosteronism, 30 with essential hyper...

Douglas-fir is the most commercially important timber species in the US Pacific Northwest due to its ecological prevalence and its superior wood attributes, especially strength and stiffness properties that make it highly prized for structural applications. Its economic significance has led to extensive establishment and management of plantations over the last few decades. Cultural treatments a...

The importance of decreasing costs of production increases as the swine industry becomes more competitive. Costs of production can be decreased through an organized selection program focused on genetic improvement in economic traits. The most competitive producers will use a swine-breeding program, which minimizes cost of production and maximizes return on investment. A clear understanding of g...