An ergonomic evaluation of infant life jackets: Donning time & donning accuracy

Canada is considering the development of a new standard for infant/child life jackets. Eight currently available (approved and non-approved) infant/child life jackets were procured for evaluation. Fifty-six participants were chosen as a sample of convenience from the general public for testing. The life jackets were divided into two groups of four, which were donned on a soft infant manikin procured from the Red Cross. In 224 attempts at donning, only 43 (19%) attempts resulted in the life jacket being donned correctly in less than 1 min. Only one life jacket came close to a good design and passed the life jacket standard for donning time and accuracy. Failure rates were observed across all the participants irrespective of age, gender, experience with children and experience with recreational marine equipment. Accuracy and speed of donning the life jacket were hampered as the number of donning sub-tasks increased. It was concluded that it is possible to design a life jacket that can be donned correctly in under 1 min. The life jacket must be of simple, intuitive design and fall naturally into the anatomical shape of the child. A minimum number of ties, zips and clips should be used in the design, and if such connectors are used they should be color coded or of different shapes and sizes to avoid confusion.     

藏在深山人未识：—介绍几个Delphi控件／工具

本文将重点介绍低价Delphi控件中的几个有趣的工具。涉及的内容有:异常处理,实现拖放,以及如何在应用程序申加入“每日一帖”对话框。     

Risk aversion in rats (Rattus norvegicus) under varying levels of resource availability.

Five male Wistar rats chose between a certain prospect and an uncertain prospect having equal expected value under varying levels of resource (water) availability. In contrast to results found with granivorous birds and common shrews (Sorex araneus), the rats did not switch from risk aversion (choosing the certain prospect) to risk preference (choosing the uncertain prospect) as resource availability varied from surplus to deficit, even though deficits were maintained for extended periods of time. Rather, Ss displayed an approximately constant level of risk aversion throughout. Explanations for these differences are offered in terms of procedural differences between this and earlier studies and in terms of differential behavioral patterns of relatively large organisms with large internal resource stores relative to their daily resource requirements. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thrombospondin-1 expression in human myometrium before and during pregnancy, before and during labor, and in human myometrial cells in culture

The activation of latent transforming growth factor beta (L-TGFbeta) is essential for the action of TGFbeta, which, in turn, is involved in the regulation of expression of some progesterone-responsive genes. One mechanism by which TGFbeta is activated involves thrombospondin (TSP), a protein that binds extracellular proteins. Immunoreactive TSP (irTSP) protein and TSP-1 mRNA in myometrial tissues of ovulatory and pregnant women were localized by immunohistochemistry and in situ hybridization. IrTSP and TSP-1 mRNA were randomly distributed in myometrial smooth muscle cells of some, but not all, tissues of pregnant women at term before labor; but in some areas of most of these tissues, irTSP was intense and commonly localized extracellularly. Intense irTSP and TSP-1 mRNA in myocytes were more common in myometrium during labor. In myometrium from ovulatory women (n = 26), irTSP was localized primarily in vascular smooth muscle cells and was detected occasionally in scattered myocytes. Little TSP-1 mRNA was demonstrable by in situ hybridization in vessels or myocytes of myometrial tissue from ovulatory women (n = 7). By Northern analysis of total RNA, TSP-1 mRNA was detected in myometrial tissue of pregnant women and in human myometrial smooth muscle cells in culture. The levels of TSP-1 mRNA in myometrial tissues of pregnant women during labor (n = 18) were greater than those in myometrium at > 37 wk gestation before labor began (n = 25, p < 0.001). The ratios of TSP-1 to glyceraldehyde 3-phosphate dehydrogenase mRNAs in 3 myometrial tissues during oxytocin-induced labor were not statistically different from those in myometrium during spontaneous labor but were greater than those in myometrium before labor (p < 0.05). The level of TSP-1 mRNA in confluent human myometrial cells in culture was relatively high, was increased by treatment with fetal bovine serum, and was decreased by treatment with platelet-derived growth factor or activators of adenylyl cyclase or protein kinase C. Myometrial cells in culture constitute a useful model for studying the regulation of TSP-1 gene expression in human myometrium.     

Behavioral genetics and evolutionary psychology: unified perspective on personality research

Behavioral geneticists and evolutionary psychologists have generally pursued human behavioral analyses with little theoretical or methodological exchange. However, significant benefits might accrue from increased communication between these disciplines. The primary goals of this article are (1) to identify meaningful junctures between behavioral genetics and evolutionary psychology, (2) to describe behavioral genetic research designs and their applications to evolutionary analyses, and (3) to reassess current personality research in light of behavioral genetic and evolutionary concepts and techniques. The five-factor model of personality is conceptualized as subsuming variation in normative species-typical systems with adaptive functions in the human environment of evolutionary adaptation. Considered as universal evolved mechanisms, personality systems are often seen in dynamic conflict within individuals and as highly compartmentalized in their functioning between settings. However, genetically influenced individual differences in personality may also be understood within an evolutionary framework. Studies of the heritability of personality traits indicate broad-sense heritabilities in the 0.40-0.50 range with evidence of substantial nonadditive genetic variation and nonshared environmental influences. Evidence indicates that evolutionary theory (e.g., inclusive fitness theory) predicts patterns of social interaction (e.g., cooperation and bereavement) in relatives. Furthermore, variation in personality may constitute a range of viable strategies matching the opportunities available in the complex niche environment of human societies. Within this wide range of viable strategies, personality variation functions as a resource environment for individuals in the sense that personality variation is evaluated according to the interests of the evaluator (e.g., friendships, coalitions, or mate choice).     

Fabrication of high frequency two-dimensional nanoactuators forscanned probe devices

The authors have developed an integrated silicon process that uses suspended single crystal silicon (SCS) structures to fabricate x-y capacitive translators and high aspect ratio conical tips for scanned probe devices. The integrated nanomechanical device design and the process sequence include methods to form integrated tunneling tip pairs and to produce electrical isolation, contacts, and conductors. Each device occupies a nominal area of 40 μm×40 μm. These devices include a novel self-aligned tip-above-a-tip tunneling structure and capacitive x-y translators defined by electron beam lithography and the thermal oxidation of silicon. The x-y translators produce a maximum x-y displacement of ±200 nm for an applied voltage of 55 V. The low mass (2×10^-13 kg), rigid structure has a measured fundamental mechanical resonant frequency of 5 MHz     

Using strain rate sensitivity measurements to determine phase relations in A430 stainless steel

Precision strain rate sensitivity measurements have been used to determine the solid solution component of interstitials in ferritic stainless steel. The measurements are based on activation volume of dislocation-solute interaction. Under an instantaneous strain rate change, a load drop occurs which is inversely proportional to the activation volume. By correlating the measured response with heat treatments a pseudo-binary Nb(C,N) solvus was determined. Such a phase diagram for a specific stainless steel alloy is useful for delineating hot-working conditions. The technique was also able to detect the presence of fine Guinier-Preston zone type of precipitates that formed during quenching and were aligned with the {001} planes of the matrix.