Rapid Desensitization of Lipolysis in the Visceral and Subcutaneous Adipocytes of Rats

In adipocytes, short and long term stimulation of β adrenergic receptors (βAR) induces the desensitization to catecholamines, leading to a decrease in the intracellular accumulation of cAMP, but the roles played by this in lipolysis is not clear. In this study, we assessed the catecholamine-induced desensitization of lipolysis and compared this in adipocytes isolated from visceral and subcutaneous fat tissues of rats. When adipocytes were pretreated with isoproterenol (ISO), the norepinephrine (NE)-induced lipolysis was significantly reduced dose- and time-dependently. A similar reduction of the lipolytic response was also found in NE-, dobutamine-, terbutaline- or BRL37344-induced lipolysis. The ISO- and each βAR agonist-induced lipolysis in the visceral fat was not only higher than in the subcutaneous fat, but also markedly reduced by ISO- or NE-pretreatment. These results showed that short-term treatment of three subtypes of βAR by each agonist induces a rapid reduction in the lipolytic response to βAR stimulation. This suggests some common mechanism for the rapid desensitization of βAR-agonist-induced lipolysis, in contrast with previous reports on the characteristics of βAR subtypes. In addition, the regional difference of adipose tissue not only in inducing lipolysis but also in rapid desensitization was also apparent.     

Parallel BDD-based monolithic approach for acoustic fluid-structure interaction

Parallel BDD-based monolithic algorithms for acoustic fluid-structure interaction problems are developed. In a previous study, two schemes, NN-I + CGC-FULL and NN-I + CGC-DIAG, have been proven to be efficient among several BDD-type schemes for one processor. Thus, the parallelization of these schemes is discussed in the present study. These BDD-type schemes consist of the operations of the Schur complement matrix-vector (Sv) product, Neumann-Neumann (NN) preconditioning, and the coarse problem. In the present study, the Sv product and NN preconditioning are parallelized for both schemes, and the parallel implementation of the solid and fluid parts of the coarse problem is considered for NN-I + CGC-DIAG. The results of numerical experiments indicate that both schemes exhibit performances that are almost as good as those of single solid and fluid analyses in the Sv product and NN preconditioning. Moreover, NN-I + CGC-DIAG appears to become more efficient as the problem size becomes large due to the parallel calculation of the coarse problem.     

Interfacial characterization of joint between mild steel and aluminum alloy welded by resistance spot welding

The interfacial characteristics of resistance spot welded steel–aluminum alloy joint have been investigated using electron microscopy. The results reveal that reaction product FeAl₃ is generated in the peripheral region of the weld while a reaction layer consisting of Fe₂Al₅ adjacent to steel and FeAl₃ adjacent to aluminum alloy forms in the central region of the weld, and that the morphology and thickness of the reaction layer vary with the position at the welding interface.     

Ethos of independence across regions in the United States: The production-adoption model of cultural change.

Contemporary U.S. culture has a highly individualistic ethos. Nevertheless, exactly how this ethos was historically fostered remains unanalyzed. A new model of dynamic cultural change maintains that sparsely populated, novel environments that impose major threats to survival, such as the Western frontier in the United States during the 18th and 19th centuries, breed strong values of independence, which in turn guide the production of new practices that encourage self-promotion and focused, competitive work. Faced with few significant threats to survival, residents in traditional areas are likely to seek social prestige by adopting existing practices of other, higher status groups. Because of both the massive economic success of the frontier and the official endorsement of the frontier by the federal government, eastern residents of the United States in the 18th and 19th centuries may have actively adopted the frontier practices of independence, thus incorporating the frontier ethos of independence to form the contemporary U.S. national culture. Available evidence is reviewed, and implications for further research on cultural change are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of butt welding of polymeric materials based on softening and stirring effects by hot tool

In this study, new butt welding technique was proposed to join polymeric materials in which the polymeric material is softened by a heated tool due to the Joule effect heating of the electric current flow through the tool, and the coalescence of material is done by the stirring action due to the tool rotation. A 3 mm-thick Polycarbonate (PC) sheets were joined in various joining conditions, from which joining mechanism, mechanical properties of joints and process parameters affecting joint performance were investigated. In the experiments, in situ observation with a CCD camera and material temperature measurement during the process, as well as the observation of surface appearance and cross section of the joint and tensile test were performed for these purposes. It was shown from the in situ observation and material temperature measurement that the molten and softened region is formed around the weld tool. It was also shown that sufficient heat input was required to form sound joints with acceptable performance, which depended upon the joining speed and amount of electric current flow through the tool. The observation of joint appearance and cross section revealed that the joint with comparable thickness to base material was obtained under the condition of revolution pitch below 0.08 mm, defined by the ratio of joining speed to tool rotation. It is noticed that joints obtained from the proper conditions have the same mechanical properties as the base material, and that the process parameters of this method were tool rotation speed, welding speed and amount of electric current. These results suggest proposed method is useful for joining the polymeric materials.     

Water‐saving approaches for improving wheat production

The greatest fear of global climate change is drought. World‐wide, 61% of countries receive rainfall of less than 500 mm annually; domestication of wheat first occurred in such a semiarid region of southwestern Asia, and it seems that wheat foods originally came from dryland gardens. Wheat plants respond to drought through morphological, physiological and metabolic modifications in all plant parts. At the cellular level, plant responses to water deficit may result from cell damage, whereas other responses may correspond to adaptive processes. Although a large number of drought‐induced genes have been identified in a wide range of wheat varieties, a molecular basis for wheat plant tolerance to water stress remains far from being completely understood. The rapid translocation of abscissic acid (ABA) in shoots via xylem flux, and the increase of ABA concentration in wheat plant parts correlate with the major physiological changes that occur during plant response to drought. It is widely accepted that ABA mediates general adaptive responses to drought. For a relatively determinate target stress environment, and with stable genotype × environment interaction, the probability for achieving progress is high. This approach will be possible only after we learn more about the physiology and genetics of wheat plant responses to water stress and their interactions. The difficulties encountered by molecular biologists in attempting to improve crop drought tolerance are due to our ignorance in agronomy and crop physiology and not to lack of knowledge or technical expertise in molecular biology. Copyright © 2005 Society of Chemical Industry     

Effect of an Nb2O5 nanolayer coating on ZnO electrodes in dye-sensitized solar cells

Nanostructured porous zinc oxide electrodes for use in dye-sensitized solar cells (DSSCs) were coated with thin niobium oxide layers by using sol–gel transformation of niobium pentaethoxide in air. Coating solutions were prepared by mixing niobium pentaethoxide and ethanol. A dip-coating technique was adopted at a low withdrawal speed of 100 μm s⁻¹. The coated electrodes were then heat-treated at temperatures between 400 and 600 °C. The presence of niobium in the coated electrodes was confirmed by X-ray photoelectron spectroscopy. As expected, the niobium oxide layers worked as an energy barrier between the ZnO electrode and electrolyte. Open-circuit voltage (V_OC) of the cells using the coated electrodes was then enhanced up to 0.768 V, which was attributable to the suppression of the recombination of photogenerated electrons with oxidized species in electrolytes. An additional benefit of the coating was that grain growth of ZnO particles in the electrodes was hindered and short-circuit photocurrent density (J_SC) was kept relatively high due to large amounts of adsorbed dye. An overall light-to-electricity conversion efficiency was increased to a maximum of 5.19%, indicating that the proper coating technique was the key for improving the performance of ZnO-based DSSCs.     

Divergent consequences of success and failure in Japan and North America: An investigation of self-improving motivations and malleable selves.

Self-enhancing and self-improving motivations were investigated across cultures. Replicating past research, North Americans who failed on a task persisted less on a follow-up task than those who succeeded. In contrast, Japanese who failed persisted more than those who succeeded. The Japanese pattern is evidence for a self-improving orientation: Failures highlight where corrective efforts are needed. Japanese who failed also enhanced the importance and the diagnosticity of the task compared with those who succeeded, whereas North Americans did the opposite. Study 2 revealed that self-improving motivations are specific to the tasks on which one receives feedback. Study 3 unpackaged the cultural differences by demonstrating that they are due, at least in part, to divergent lay theories regarding the utility of effort. Study 4 addressed the problem of comparing cultures on subjective Likert scales and replicated the findings with a different measure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Seismic analysis of nuclear power plants by using three-dimensional finite element models: a review

ABSTRACT

Seismic design of nuclear power plants (NPPs) is important for ensuring their integrity during earthquakes. Seismic analysis has been conducted using lumped mass beam models (LMBMs) for the design of plants in Japan, whereas three-dimensional (3D) finite element models (FEMs) have been used for novel plants outside Japan. The purposes of this study are to organize issues related to the development and application of 3D FEMs for seismic analysis of Japanese NPPs and to indicate future study directions. To organize these issues, the authors systematically investigated: (1) international guides and standards related to seismic analysis and (2) 3D FEMs of novel NPPs outside Japan. By considering other studies on the issues, the authors suggest directions for future studies. Resolving the issues will contribute to application of 3D FEMs for seismic analysis in the design of Japanese NPPs.