Behaviorally functional opioid systems in infant rats: II. Evidence for pharmacological, physiological, and psychological mediation of pain and stress.

Two experiments, with 160 10-day-old Sprague-Dawley rat pups, examined the behavioral characteristics of the neonatal opioid system during distressful situations, using a modification of the hot-plate paw-lick test. Ss were analgesic to heat following intraperitoneal morphine (0.5 mg/kg). Subcutaneous naloxone (0.5 mg/kg) prevented the analgesia. Morphine analgesia was significantly greater in Ss group-isolated from the dam. Saline controls group-isolated from the dam exhibited longer latencies than their nest-housed siblings. Individual isolation for 5 min markedly increased paw-withdrawal latency, and this effect was naltrexone reversible. Analgesia was not seen when Ss were tested directly from the nest or when grouped with others for 5 min. It is suggested that the opioid systems for stress and pain are functional in 10-day-old rats and that short-term isolation from the dam is a probable natural stressor modulated by endogenous opioid release. (51 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Job control and job strain: A test of three models.

Examined the relationship between job control and job strain. Three models of that relationship provide a framework for the study hypotheses: (H1) Control is inversely related to job strain, (H2) job demands interact with job control such that job strain will be highest when job demands are high and job control is low, and (H3) strain increases as the discrepancy between actual and desired levels of job control increases. Study participants (N?=?316) were health care workers in 2 hospitals in the northeastern US. Objective measures of job control and job demands were obtained through supervisor evaluations of incumbents' job characteristics, and perceptual measures were obtained through incumbents' self-reports. Results provide support for Hypotheses 1 and 3; little support was found for an interaction between job control and job demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of low-temperature aging on AISI 444 steel

The consequences of aging at 400 and 475 °C on the mechanical properties, corrosion resistance, and magnetic properties of the ferritic stainless steel (SS) AISI 444 were investigated. Age hardening was measured as a function of aging time at both temperatures and was found to be more intense at 475 °C. The localized corrosion susceptibility increased, while the impact toughness decreased with aging time. These two effects were also more important at 475 °C. Unlike duplex SSs, AISI 444 did not present any variation in coercive force or Curie temperature with aging time. The effects on the Mössbauer spectra were also determined and analyzed.     

New approach for the prediction of azeotropy in binary systems

A new approach for the prediction of azeotrope formation between components in a mixture, that does not require vapor–liquid equilibrium calculations, is presented. The method employs neural networks to correlate azeotropic data for binary mixtures with a series of macroscopic and microscopic properties of the pure components, without explicit consideration of non-ideality of mixture. The model fails to make a clear prediction regarding azeotropy in only a relatively small number of situations in which structurally homologous molecules are known to exhibit quite distinct azeotropic behavior.     

Signal differentiation through a Green''s function approach

We introduce a new approach for the design of differential operators, based on the Green's function solution to a signal matching equation. Its use is illustrated by the construction of step-edge enhancement filters whose performance figures are comparable, and even superior, to those reported in the literature.     

Electrochemical characterization of titanium biomaterials using the Mini-cell System

The aim of this work was the electrochemical characterization of modified Titanium surfaces for implants with help of the Mini-cell System (MCS). The materials tested were Cp titanium specimens, designed for animal experiments, with 8 mm length and 4 mm diameter, with different surface conditions: one had machined surface, the other was blasted with a bioceramic (GB14+AP40) and the third was blasted with aluminum oxide. Roughness measurements were also made on the materials. The results showed that MCS has sensitivity to detect differences in the electrochemical point of view due to surface modifications. The differences between the materials are small, but systematic. The aluminum oxide blasted material had the highest current density, however due to the roughness increase. The material with bioceramics blasting had the highest chemical activity. The higher activity of the bioceramics treated surface was explained as (i) an interaction between the modified surface and electrolyte; or (ii) the calcium phosphate dissolves in the electrolyte and leaves the surface of the metal, and then the free metal reacts immediately to form new titanium oxide. These results may help to explain the biological effects observed by modified surfaces, in particular with bioceramics.     

A decomposition‐based approach to uncertainty analysis of feed‐forward multicomponent systems

To support effective decision making, engineers should comprehend and manage various uncertainties throughout the design process. Unfortunately, in today's modern systems, uncertainty analysis can become cumbersome and computationally intractable for one individual or group to manage. This is particularly true for systems comprised of a large number of components. In many cases, these components may be developed by different groups and even run on different computational platforms. This paper proposes an approach for decomposing the uncertainty analysis task among the various components comprising a feed‐forward system and synthesizing the local uncertainty analyses into a system uncertainty analysis. Our proposed decomposition‐based multicomponent uncertainty analysis approach is shown to be provably convergent in distribution under certain conditions. The proposed method is illustrated on quantification of uncertainty for a multidisciplinary gas turbine system and is compared to a traditional system‐level Monte Carlo uncertainty analysis approach. Copyright © 2014 John Wiley & Sons, Ltd.