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Large Responses (large + response)
Selected AbstractsDevelopment of an oxide semiconductor thick film gas sensor for the detection of total volatile organic compoundsELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 10 2010Masahiro Kadosaki Abstract Since the amendment of the Building Standards Law in 2003, the installation of ventilators is compulsory in newly built houses, because many persons suffer from indoor air pollution caused by volatile organic compounds (VOCs). The goal of this research is to develop a gas sensor that can monitor the total VOC (TVOC) gases indoors and then to control the ventilator efficiently using the sensor. In order to develop a sensor that detects TVOC, the responses of four oxide semiconductor materials to 37 different VOC gases were studied. These materials showed small responses to halogenated and aliphatic hydrocarbon gases. As a result of improving the response to these gases, among four metal oxides examined, SnO2 and WO3 showed high sensitivities by the addition of Pd and Pt. The sensing properties of SnO2 for halogenated hydrocarbon gases were greatly improved by the addition of 0.5 wt% Pd. The sensing properties of SnO2 for aliphatic hydrocarbon gases were improved by the addition of 0.7 wt% Pt. In addition, a sensor element with the addition of both platinum and palladium, that is, Pt (0.5 wt%)-Pd (0.5 wt%)-SnO2, showed a large response to many of the VOC gases examined. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(10): 34,41, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10190 [source] Discreteness and the Welfare Cost of Labor Supply Tax Distortions*INTERNATIONAL ECONOMIC REVIEW, Issue 3 2003Keshab Bhattarai We compare the welfare costs of tax distortions of labor supply in one- and two-member household discrete and continuous choice labor supply (leisure consumption) models calibrated to the same aggregate uncompensated labor supply elasticities. In the discrete models, taxes induce a large response from a subset of the population, whereas the majority of the population exhibits unchanged behavior. In contrast, the majority of the population reacts to tax changes in continuous models. Discrete choice matters as the welfare costs of similar taxes vary significantly when individuals face discrete labor supply choices from when they choose working hours continuously. [source] How to create a large response from chaotic systems: Optimal forcing functions complement the natural dynamics of a systemCOMPLEXITY, Issue 4 2006Alfred W. Hübler No abstract is available for this article. [source] A substructure shaking table test for reproduction of earthquake responses of high-rise buildingsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2009Xiaodong Ji Abstract When subjected to long-period ground motions, high-rise buildings' upper floors undergo large responses. Furniture and nonstructural components are susceptible to significant damage in such events. This paper proposes a full-scale substructure shaking table test to reproduce large floor responses of high-rise buildings. The response at the top floor of a virtual 30-story building model subjected to a synthesized long-period ground motion is taken as a target wave for reproduction. Since a shaking table has difficulties in directly reproducing such large responses due to various capacity limitations, a rubber-and-mass system is proposed to amplify the table motion. To achieve an accurate reproduction of the floor responses, a control algorithm called the open-loop inverse dynamics compensation via simulation (IDCS) algorithm is used to generate a special input wave for the shaking table. To implement the IDCS algorithm, the model matching method and the H, method are adopted to construct the controller. A numerical example is presented to illustrate the open-loop IDCS algorithm and compare the performance of different methods of controller design. A series of full-scale substructure shaking table tests are conducted in E-Defense to verify the effectiveness of the proposed method and examine the seismic behavior of furniture. The test results demonstrate that the rubber-and-mass system is capable of amplifying the table motion by a factor of about 3.5 for the maximum velocity and displacement, and the substructure shaking table test can reproduce the large floor responses for a few minutes. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cardiac and coronary function in the Langendorff-perfused mouse heart modelEXPERIMENTAL PHYSIOLOGY, Issue 1 2009Melissa E. Reichelt The Langendorff mouse heart model is widely employed in studies of myocardial function and responses to injury (e.g. ischaemia). Nonetheless, marked variability exists in its preparation and functional properties. We examined the impact of early growth (8, 16, 20 and 24 weeks), sex, perfusion fluid [Ca2+] and pacing rate on contractile function and responses to 20 min ischaemia followed by 45 min reperfusion. We also assessed the impact of strain, and tested the utility of the model in studying coronary function. Under normoxic conditions, hearts from 8-week-old male C57BL/6 mice (2 mm free perfusate [Ca2+], 420 beats min,1) exhibited 145 ± 2 mmHg left ventricular developed pressure (LVDP). Force development declined by ,15% (126 ± 5 mmHg) with a reduction in free [Ca2+] to 1.35 mm, and by 25% (108 ± 3 mmHg) with increased pacing to 600 beats min,1. While elevated heart rate failed to modify ischaemic outcome, the lower [Ca2+] significantly improved contractile recovery (by >30%). We detected minimal sex-dependent differences in normoxic function between 8 and 24 weeks, although age modified contractile function in males (increased LVDP at 24 versus 8 weeks) but not females. Both male and female hearts exhibited age-related reductions in ischaemic tolerance, with a significant decline in recovery evident at 16 weeks in males and later, at 20,24 weeks, in females (versus recoveries in hearts at 8 weeks). Strain also modified tolerance to ischaemia, with similar responses in hearts from C57BL/6, 129/sv, Quackenbush Swiss and FVBN mice, but substantially greater tolerance in BALB/c hearts. In terms of vascular function, baseline coronary flow (20,25 ml min,1 g,1) was 50,60% of maximally dilated flows, and coronary reactive and functional hyperaemic responses were pronounced (up to 4-fold elevations in flow in hearts lacking ventricular balloons). These data indicate that attention to age (and sex) of mice will reduce variability in contractile function and ischaemic responses. Even small differences in perfusion fluid [Ca2+] also significantly modify tolerance to ischaemia (whereas modest shifts in heart rate do not impact). Ischaemic responses are additionally strain dependent, with BALB/c hearts displaying greatest intrinsic tolerance. Finally, the model is applicable to the study of vascular reactivity, providing large responses and excellent reproducibility. [source] Evolutionary biology of starvation resistance: what we have learned from DrosophilaJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2007S. RION Abstract Most animals face periods of food shortage and are thus expected to evolve adaptations enhancing starvation resistance (SR). Most of our knowledge of the genetic and physiological bases of those adaptations, their evolutionary correlates and trade-offs, and patterns of within- and among-population variation, comes from studies on Drosophila. In this review, we attempt to synthesize the various facets of evolutionary biology of SR emerging from those studies. Heritable variation for SR is ubiquitous in Drosophila populations, allowing for large responses to experimental selection. Individual flies can also inducibly increase their SR in response to mild nutritional stress (dietary restriction). Both the evolutionary change and the physiological plasticity involve increased accumulation of lipids, changes in carbohydrate and lipid metabolism and reduction in reproduction. They are also typically associated with greater resistance to desiccation and oxidative stress, and with prolonged development and lifespan. These responses are increasingly seen as facets of a shift of the physiology towards a ,survival mode', which helps the animal to survive hard times. The last decade has seen a great progress in revealing the molecular bases of induced responses to starvation, and the first genes contributing to genetic variation in SR have been identified. In contrast, little progress has been made in understanding the ecological significance of SR in Drosophila; in particular it remains unclear to what extent geographical variation in SR reflect differences in natural selection acting on this trait rather than correlated responses to selection on other traits. Drosophila offers a unique opportunity for an integrated study of the manifold aspects of adaptation to nutritional stress. Given that at least some major molecular mechanisms of response to nutritional stress seem common to animals, the insights from Drosophila are likely to apply more generally than just to dipterans or insects. [source] Corticosteroid Effects on Serotonin Responses in Granule Cells of the Rat Dentate GyrusJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2001Y. J. G. Karten Abstract Granule cells in the rat dentate gyrus contain mineralocorticoid and glucocorticoid receptors to which the adrenal hormone corticosterone binds with differential affinity. These cells also express various receptor-subtypes for serotonin (5-HT), including the 5-HT1A receptor which mediates a membrane hyperpolarization accompanied by a decrease in membrane resistance. Earlier studies have shown that removal of corticosterone by adrenalectomy, particularly in the dentate gyrus, results in enhanced expression of the 5-HT1A receptor mRNA and increased 5-HT1A receptor binding capacity. This was normalized by activation of mineralocorticoid receptors or concurrent activation of both receptor types. In the present, intracellular recording study in vitro, we examined if the altered levels of 5-HT1A receptor mRNA and protein are associated with changes in the response to 5-HT. We found that the hyperpolarization and resistance decrease induced in granule cells by a submaximal (10 µM) dose of 5-HT were unaltered 2,4 days after adrenalectomy, indicating a dissociation between corticosteroid actions on 5-HT1A receptor mRNA/protein levels and functional responses to 5-HT. Subsequent occupation of mineralocorticoid receptors in vitro significantly suppressed the 5-HT induced change in resistance, 1,4 h after steroid application. Compared to this, concurrent activation of glucocorticoid receptors led to large responses to 5-HT. This modulation by steroids was not observed with a higher dose of 5-HT (30 µM). The data suggest that with moderate amounts of 5-HT, corticosteroids affect the information flow through the dentate gyrus such that excitatory transmission is promoted with predominant mineralocorticoid receptor activation and attenuated with additional glucocorticoid receptor occupation. [source] | |||||||||||||