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Drive
Kinds of Drive Terms modified by Drive Selected AbstractsDRIVE,Dispatching Requests Indirectly through Virtual EnvironmentCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2010Hyung Won Choi Abstract Dispatching a large number of dynamically changing requests directly to a small number of servers exposes the disparity between the requests and the machines. In this paper, we present a novel approach that dispatches requests to servers through virtual machines, called Dispatching Requests Indirectly through Virtual Environment (DRIVE). Client requests are first dispatched to virtual machines that are subsequently dispatched to actual physical machines. This buffering of requests helps to reduce the complexity involved in dispatching a large number of requests to a small number of machines. To demonstrate the effectiveness of the DRIVE framework, we set up an experimental environment consisting of a PC cluster and four benchmark suites. With the experimental results, we demonstrate that the use of virtual machines indeed abstracts away the client requests and hence helps to improve the overall performance of a dynamically changing computing environment. Copyright © 2009 John Wiley & Sons, Ltd. [source] INTRODUCING DESIRABLE TRANSGENES INTO INSECT POPULATIONS USING Y-LINKED MEIOTIC DRIVE,A THEORETICAL ASSESSMENTEVOLUTION, Issue 4 2007Yunxin Huang The use of genetic drive mechanisms to replace native mosquito genotypes with individuals bearing antipathogen transgenes is a potential strategy for repressing insect transmission of human diseases such as malaria and dengue. Antipathogen transgenes have been developed and tested, but efficient gene drive mechanisms are lacking. Here we theoretically assess the feasibility of introducing antipathogen genes into wild Aedes aegypti populations by using a naturally occurring meiotic drive system. We consider the release of males having both a Y-linked meiotic drive gene and an X-linked drive-insensitive response allele to which an antipathogen gene is linked. We use mathematical models and computer simulations to determine how the post-introduction dynamics of the antipathogen gene are affected by specific genetic characteristics of the system. The results show that when the natural population is uniformly sensitive to the meiotic drive gene, the antipathogen gene may be driven close to fixation if the fitness costs of the drive gene, the insensitive response allele, and the antipathogen gene are low. However, when the natural population has a small proportion of an X-linked insensitive response allele or an autosomal gene that strongly reduces the effect of the drive gene, the antipathogen gene does not spread if it has an associated fitness cost. Our modeling results provide a theoretical foundation for further experimental tests. [source] MEIOTIC DRIVE AND SEX CHROMOSOME CYCLINGEVOLUTION, Issue 5 2004David W. Hall Abstract , Sex-linked meiotic drive is found in a broad variety of taxa, including insects, birds, and mammals. In populations of some species, we see four types of sex chromosomes segregating: normal and driving X chromosomes and susceptible and resistant Y chromosomes. A theoretical analysis shows that a stable four-chromosome equilibria is a more common outcome in these systems than previously recognized. Cycling of sex chromosome frequencies and associated changes in the sex ratio are other predicted outcomes. The absence of cycling in nature may be due to migration among populations. [source] WHAT FEATURES DRIVE RATED BURGER CRAVEABILITY AT THE CONCEPT LEVEL?JOURNAL OF SENSORY STUDIES, Issue 1 2004JACQUELINE BECKLEY ABSTRACT This paper deals with the analysis of drivers for self-defined craveability assessed in an Internet-based, conjoint analysis task. The stimuli comprised 36 descriptions of restaurant hamburgers, including product features, benefits, restaurant names, and emotional reactions that might ensue after eating the hamburger. Elements were combined into concepts by experimental design, and the resulting concepts evaluated by 145 respondents, on the attribute of craveability. Models relating the presence/absence of concept elements to ratings revealed that statements about the hamburger itself were the most powerful, but that no single element was highest across all the respondents. Segmentation of the 145 individuals by the pattern of their individual utilities revealed four key segments. These are Elaborates who may be sensory-oriented and respond strongly to product descriptions; Classics who like the notion of a grilled hamburger; Imaginers who respond to restaurant name and advertising copy; and Emotionals who respond to statements about food to descriptions how the eater feels after consumption. [source] STRIVE FOR 5 MEMBERSHIP DRIVENURSING IN CRITICAL CARE, Issue 4 2010Vicky Quinn No abstract is available for this article. [source] ERECTILE FUNCTION, SEXUAL DRIVE, AND EJACULATORY FUNCTION ALTER RECONSTRUCTIVE SURGERY FOR ANTERIOR URETHRAL STRICTURE DISEASEBJU INTERNATIONAL, Issue 6 2007Javier Ponce De León No abstract is available for this article. [source] The relationship between ,workaholism', basic needs satisfaction at work and personalityEUROPEAN JOURNAL OF PERSONALITY, Issue 1 2010Cecilie Schou Andreassen Abstract The aim of this study was to examine correlates of ,workaholism' components (Work Involvement, Drive, Enjoyment of Work). A cross-occupational sample of 661 Norwegian employees in six different organizations completed a web-based survey measuring ,workaholism', basic needs satisfaction at work and personality. Needs satisfaction at work was positively related to Enjoyment of Work, and negatively to Drive. Conscientiousness was positively related to all ,workaholism' components; Extraversion and Openness to Work Involvement and Enjoyment of Work; and Neuroticism to Drive. Negative relations were found between Neuroticism and Enjoyment of Work, and Agreeableness and Drive. Although the associations were rather weak, the findings give reason to differentiate between enthusiastic and non-enthusiastic ,workaholic' characteristics, which were consistent with predictions taken from central theories on ,workaholism'. Copyright © 2009 John Wiley & Sons, Ltd. [source] Association of 5-HTT gene polymorphism, platelet MAO activity, and drive for thinness in a population-based sample of adolescent girlsINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 5 2008Kirsti Akkermann MSc Abstract Objective: Several lines of evidence suggest that alterations in serotonergic activity contribute to the pathophysiology of abnormal eating behaviors. Since platelet monoamine oxidase (MAO) activity and the 5-HT transporter gene promoter polymorphism (5-HTTLPR) have been associated with eating disorders, the knowledge from a population-based sample may provide useful information which changes in 5-HT function observed in eating disorders represent trait vs. state effects. Method: The sample was based on both cohorts of the Estonian Children Personality, Behavior and Health Study (ECPBHS). The current study was conducted during the second follow-up where altogether 82% from the original sample was recruited. EDI-2 subscales,Drive for Thinness and Bulimia,were used to determine eating attitudes and behaviors. Platelet MAO activity was measured and the participants were genotyped for the 5-HTTLPR. Results: Allelic variation of 5-HTTLPR or platelet MAO activity were not independently associated with drive for thinness or binge eating, but girls homozygous for the 5-HTTLPR long allele and with high platelet MAO activity, both considered indicators of a higher capacity 5-HT system, exhibited higher scores of drive for thinness. Conclusion: The results suggest that drive for thinness is the highest in girls with the presence of two markers of higher serotonergic capacity. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008 [source] Eating problems, body image disturbances, and academic achievement: Preliminary evaluation of the eating and body image disturbances academic interference scaleINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2008Tovah Yanover MA Abstract Objective: To examine the relationships between a new scale, the Eating and Body Image Disturbances Academic Interference Scale (EBIDAIS), and measures of eating disturbance, body image, and academic achievement. Method: One thousand five hundred eighty-four college undergraduates completed the measures in an online survey and were awarded class credit for their participation. Measures included the Eating Disorder Inventory Bulimia, Drive for Thinness, Body Dissatisfaction, and Perfectionism subscales. Grade point average (GPA) was also reported. Results: Academic interference and GPA were significantly correlated, indicating that higher interference scores were related to lower GPA. EBIDAIS was also significantly correlated with drive for thinness, bulimia, and body dissatisfaction, but was not significantly associated with perfectionism. The correlation between interference and GPA was substantially higher for a subsample of individuals who scored in the elevated range on eating and body dissatisfaction. Conclusion: Academic interference may be a relatively unexamined, but potentially important, outcome for individuals who experience eating problems and body image disturbance. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2008 [source] Body dissatisfaction and drive for thinness in young adult twinsINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2005Anna Keski-Rahkonen MD Abstract Objective We explored correlates of the Eating Disorder Inventory subscales Body Dissatisfaction (BD) and Drive for Thinness (DT) and genetic and environmental influences on these traits. Method In a population-based sample of 4,667 Finnish twins aged 22,27 years, we conducted twin modeling to explore genetic and environmental contributions to body dissatisfaction and drive for thinness. Logistic regression was used for the correlational analysis. Results Various eating and body size-related factors and psychosomatic symptoms were significantly associated with high body dissatisfaction and drive for thinness in both genders. In women, early puberty onset, early initiation of sexual activity, and multiple sex partners were statistically significant risk factors of body dissatisfaction. In gender-specific univariate twin models, additive genes accounted for 59.4% (95% confidence interval [CI] = 53.2,64.7%) of the variance in body dissatisfaction and for 51.0% (95% CI = 43.7,57.5%) of the variance in drive for thinness among females, but for none of the variance among males. Discussion There are very distinct gender differences in the heritability patterns of body dissatisfaction and drive for thinness in young adults. © 2005 by Wiley Periodicals, Inc. [source] A prospective study of disordered eating among sorority and nonsorority womenINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2004Kelly C. Allison Abstract Objective The current study examined disordered eating prospectively among sorority and nonsorority women. Method University women were surveyed during their first, second, and third undergraduate years. Disordered eating, depression, self-esteem, body mass index (BMI), and ideal weight were measured. Results Disordered eating did not differ between the groups before women joined sororities. By Time 3, sorority women reported higher Eating Disorder Inventory (EDI) Drive for Thinness subscale scores than nonsorority women, but the EDI Bulimia and Body Dissatisfaction subscales did not differ. BMI, ideal weights, depression, and self-esteem did not differ. Conclusions Women who join sororities are similar to those who do not in their baseline levels of disordered eating, but they maintain more rigorous attitudes and behaviors regarding dieting over the course of their higher education. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 35: 354,358, 2004. [source] PRODUCTION AND RELEASE OF GEOSMIN BY THE CYANOBACTERIUM OSCILLATORIA SPLENDIDA ISOLATED FROM A PHOENIX WATER SOURCEJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Hu, Q.1, Sommerfeld, M.1 Lowry, D.1, Dempster, T.1, Westerhoff, P.2, Baker, L.3, Bruce, D. & Nguyen, M. L.2 1Department of Plant Biology and 2Department of Civil and Environmental Engineering, Arizona State University, Tempe, Arizona 85287; 3Baker Environmental Consulting, 8001 Greenwood Drive, Moundview, MN 55112 Geosmin is a common component of the off-flavors detected in the drinking water supply sources of metropolitan Phoenix (Arizona). A cyanobacterium, Oscillatoria splendida, was isolated from source water during incidents of elevated geosmin production and was implicated as a cause of earthy/musty off-flavors in the drinking water. Production of geosmin was found to be constitutive in O. splendida during all growth stages. Effects of environmental parameters on the growth characteristics, and on production and release of geosmin by O. splendida, was studied under laboratory conditions. The specific growth rate and cell-bound geosmin increased with increasing temperature from 12 to 26 °C, the range of water temperatures that occur in the drinking water supply. On a per-chlorophyll a basis, however, more geosmin was released from the cells at lower temperatures. An inverse relationship was evident between light intensity and O. splendida growth and the release of geosmin. Cell-bound geosmin, however, was higher at higher light intensities. Dark incubation initially stimulated the biosynthesis of geosmin, whereas a prolonged period of darkness (2-3 weeks) resulted in massive release of geosmin into the culture medium from lysis and cellular decomposition. Dissolved nitrogen appeared to be the limiting nutrient for O. splendida in the local water supply source. When nitrate was added to laboratory cultures, both growth and geosmin production increased. These results will be discussed in context with episodes of off-flavors in drinking waters in metropolitan Phoenix, Arizona. [source] Influence of Alcohol Use Experience and Motivational Drive on College Students' Alcohol-Related CognitionALCOHOLISM, Issue 8 2009Roisin M. O'Connor Background:, Cognitive processes are thought to be pivotal to risk for heavy drinking. However, few studies have examined the alcohol cue-activated positive and negative semantic memory networks that may be pivotal to drinking behavior. Moreover, much is to be understood about the influences of cognitive processes, particularly in high-risk drinking samples such as college students. The current study examines the sequential process of alcohol cues activating valenced semantic memory networks, and the influences of prior drinking experience and individual differences in motivational drive on this automatic (implicit) cognitive process. Methods:, Participants (N = 138, 52% women) were college freshmen prescreened to represent the full range of drinking experience (i.e., current abstainers, light and heavy drinkers). Participants completed self-reports of past month alcohol use, and individual differences in behavioral inhibition system (BIS) and behavioral approach/activation system (BAS). Alcohol cue-elicited positive and negative semantic memory networks were assessed using a priming task. Results:, Results from the priming task revealed that for light drinkers alcohol cues were equally as likely to activate positive and negative semantic memory networks, suggesting relatively neutral cue-elicited alcohol attitudes. Conversely, for heavy drinkers, alcohol cues more readily activated positive relative to negative semantic memory networks, suggesting relatively positive cue-elicited alcohol attitudes. Furthermore, positive alcohol cue-elicited semantic memory networks (positive attitudes) were evident for individuals characterized by a strong BAS and weak BIS (as hypothesized) and those characterized by a weak BAS and weak BIS. Conclusions:, The findings suggest that alcohol-cue elicited positive semantic memory networks may be pivotal to risk for heavy drinking. Specifically, it is via the influence on this cognitive process that prior drinking experience and individual differences in motivational drive, respectively, may maintain and predispose individuals to risk for heavy alcohol use. [source] Poverty and Downward Mobility in the Land of OpportunityAMERICAN ANTHROPOLOGIST, Issue 3 2001Catherine Kingfisher Falling from Grace: Downward Mobility in the Age of Affluence. Katherine S. Newman. Berkeley; University of California Press, 1999. 328 pp. "So You Think. Drive. Cadillac?": Welfare Recipients' Perspectives on the System and Its Reform. Karen Seccombe. Boston: Allyn and Bacon, 1999. 246 PP. Braving the Street: The Anthropology of Homelessness. Irene Glasser and Rae Bridgman. New York: Berghahn Books, 1999. 132 pp. [source] The Comparative Effects of Drive and Test Stimulus Intensity on Myocardial Excitability and VulnerabilityPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2000HOWARD S. FRIEDMAN The number and intensity of stimuli that set basic cycle length in cardiac electrophysiological studies can influence the electrical properties assessed by extrastimuli. The relative contribution of drive (S1) and test (S2) stimulus intensity in defining myocardial excitability and vulnerability has not been reported. The purpose of this investigation was to assess this interaction and to determine whether a trial and ventricular findings differed. The effects of S1 and S2 intensity on a trial and ventricular stimulus-intensity-refractory-period curves were determined in open-chest dogs: comparisons were made between curves with S1 intensity varied between diastolic threshold (DT) and 10 mA and S2 intensity maintained at DT and those with S, intensity maintained at DT and S2 intensity varied between DT and 10 mA. S1 -S2 was held constant and S1 -S2 varied. The effects of different stimulation sites, cycle length, number of stimulations, and neural blockade were assessed. S3 intensity amplification shifted atrial stimulus-intensity-refractory period curves in the direction of increased excitability and vulnerability; the changes were, more pronounced than those obtained by modulating S2 intensity. The changes produced by increasing S1 intensity were evident at different cycle lengths and were enhanced by an increased number of stimulations, but were not evident when S1 and S2 were delivered at different atrial sites. Although beta-blockade attenuated the effects of increasing S1 intensity somewhat, the addition of cholinergic blockade virtually abolished it. Ventricular refractoriness was also changed by modulation of S1 intensity, but the changes were less striking. In the atrium, modulation of S1 intensity has greater effects of stimulus-intensity-refractory-period relations than modulation ofS2 intensity; in the ventricle, the converse is true. [source] Migration and diversity in Roman Britain: A multidisciplinary approach to the identification of immigrants in Roman York, EnglandAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Stephany Leach Abstract Previous anthropological investigations at Trentholme Drive, in Roman York identified an unusual amount of cranial variation amongst the inhabitants, with some individuals suggested as having originated from the Middle East or North Africa. The current study investigates the validity of this assessment using modern anthropological methods to assess cranial variation in two groups: The Railway and Trentholme Drive. Strontium and oxygen isotope evidence derived from the dentition of 43 of these individuals was combined with the craniometric data to provide information on possible levels of migration and the range of homelands that may be represented. The results of the craniometric analysis indicated that the majority of the York population had European origins, but that 11% of the Trentholme Drive and 12% of The Railway study samples were likely of African decent. Oxygen analysis identified four incomers, three from areas warmer than the UK and one from a cooler or more continental climate. Although based on a relatively small sample of the overall population at York, this multidisciplinary approach made it possible to identify incomers, both men and women, from across the Empire. Evidence for possible second generation migrants was also suggested. The results confirm the presence of a heterogeneous population resident in York and highlight the diversity, rather than the uniformity, of the population in Roman Britain. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] Mulholland Drive (2001): A self-psychology perspectiveTHE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 2 2007Joseph Barbera [source] Issues in the Drive to Measure Liabilities at Fair ValueAUSTRALIAN ACCOUNTING REVIEW, Issue 21 2000MICHAEL E. BRADBURY This paper compares the discussion on liability measurement in Accounting The0y Monograph 10 with the liability measurement requirements in recent international proposals on accounting for financial instruments. Rather than conducting a detailed review of the Monograph, the paper examines three major issues which wawant amplifjing, extending or criticising: What is "fair value"? Why fair value liabilities? Should fair value include an entity's own credit risk? The focus is on financial liabilities such as "plain vanilla" debt; other financial liabilities, such as insurance obligations, pensions, wawanties and environmental damage restoration involve additional considerations and are therefore not considered. [source] Assessment of male sexual function by the Brief Sexual Function InventoryBJU INTERNATIONAL, Issue 2 2006ARNSTEIN MYKLETUN OBJECTIVE To present normative data from Norway using the Brief Male Sexual Function Inventory (BSFI, the first patient self-administered questionnaire to assess male sexuality, and used in the USA) in men aged 20,79 years, examine the psychometric properties of the BSFI, explore the impact of sexual function and other variables on overall sexual satisfaction, and compare American and Norwegian normative data. SUBJECTS AND METHODS From public official address lists 3500 men aged 20,79 years were invited to take part in an anonymous questionnaire study, including the BSFI. Altogether 1185 (34%) responded, and the response rates varied with age. RESULTS There was increasingly reduced sexual function concerning drive, erection, ejaculation, and problem assessment with age, and most of the age-effect started at >50 years old. Overall sexual satisfaction followed the same trend, but with a weaker association with age. Analyses of factor structure and internal consistency of the BSFI supported a one-factor solution with good internal consistency. Drive, erection, ejaculation, and problem assessment explained 28% of the variance in overall sexual satisfaction. Being younger and having a sexual partner were also associated with high scores of overall sexual satisfaction. American and Norwegian normative data in the BSFI dimensions were markedly similar. CONCLUSION The BSFI is a short and discrete screening tool for sexual function, and for most clinical and research purposes we recommend using the BSFI as a one-dimensional scale. [source] Directed Helical Growth: A Spring-Like Behavior of Chiral Block Copolymer with Helical Nanostructure Driven by Crystallization (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Mater. Crystalline helices (PLLA crystallization directed by helical confined microdomains) and crystalline cylinders (phase transformation of helical nano structures dictated by crystallization) are obtained by controlling the crystallization temperature of PLLA with respect to the glass transition temperature of PS in PS-PLLA block copolymers; this process is described by J.-W. Chiang et al. on page 448. A spring-like behavior of the PLLA helical nanostructures embedded in the PS matrix can be driven by crystallization, so as to dictate the transformation of the helices, resulting in crystalline cylinders that might represent a possible avenue for the design of switchable large-strain actuators. [source] A Spring-Like Behavior of Chiral Block Copolymer with Helical Nanostructure Driven by CrystallizationADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Yeo-Wan Chiang Abstract The crystallization of helical nanostructure resulting from the self-assembly of a chiral diblock copolymer, poly(styrene)- b -poly(L -lactide) (PS-PLLA), is studied. Various crystalline PS-PLLA nanostructures are obtained by controlling the crystallization temperature of PLLA (Tc,PLLA), at which crystalline helices and crystalline cylinders occur while Tc,PLLA,<,Tg,PS (the glass transition temperature of PS) and Tc,PLLA,,,Tg,PS, respectively. As evidenced by selected-area electron diffraction and two-dimensional X-ray diffraction results, the PLLA crystallites under confinement reveal a unique anisotropic character regardless of the crystallization temperature. On the basis of observed uniaxial scattering results the PLLA crystallites grown within the microdomains are identified as crystals with preferential growth directions either along the [100] or along the [110]-axes of the PLLA crystalline unit cell, at which the molecular chains and the growth direction are normal and parallel to the central axes of helices, respectively. The formation of this exclusive crystalline growth is attributed to the spatial confinement effect for crystallization. While Tc,PLLA,<,Tg,PS, owing to the directed crystallization by helical confinement, the preferential crystalline growth leads to the crystallization following a helical track with growth direction parallel to the central axes of helices through a twisting mechanism. Consequently, winding crystals with specific crystallographic orientation within the helical microdomains can be found. By contrast, while Tc,PLLA,,,Tg,PS, the preferential growth may modulate the curvature of microdomains by shifting the molecular chains to access the fast path for crystalline growth due to the increase in chain mobility. As a result, a spring-like behavior of the helical nanostructure can be driven by crystallization so as to dictate the transformation of helices, resulting in crystalline cylinders that might be applicable to the design of switchable large-strain actuators. [source] Legitimacy and the Privatization of Environmental Governance: How Non,State Market,Driven (NSMD) Governance Systems Gain Rule,Making AuthorityGOVERNANCE, Issue 4 2002Benjamin Cashore In recent years, transnational and domestic nongovernmental organizations have created non,state market,driven (NSMD) governance systems whose purpose is to develop and implement environmentally and socially responsible management practices. Eschewing traditional state authority, these systems and their supporters have turned to the market's supply chain to create incentives and force companies to comply. This paper develops an analytical framework designed to understand better the emergence of NSMD governance systems and the conditions under which they may gain authority to create policy. Its theoretical roots draw on pragmatic, moral, and cognitive legitimacy granting distinctions made within organizational sociology, while its empirical focus is on the case of sustainable forestry certification, arguably the most advanced case of NSMD governance globally. The paper argues that such a framework is needed to assess whether these new private governance systems might ultimately challenge existing state,centered authority and public policy,making processes, and in so doing reshape power relations within domestic and global environmental governance. [source] Conditional Heteroskedasticity Driven by Hidden Markov ChainsJOURNAL OF TIME SERIES ANALYSIS, Issue 2 2001Christian Francq We consider a generalized autoregressive conditionally heteroskedastic (GARCH) equation where the coefficients depend on the state of a nonobserved Markov chain. Necessary and sufficient conditions ensuring the existence of a stationary solution are given. In the case of ARCH regimes, the maximum likelihood estimates are shown to be consistent. The identification problem is also considered. This is illustrated by means of real and simulated data sets. [source] 2D Random Organization of Racemic Amino Acid Monolayers Driven by Nanoscale Adsorption Footprints: Proline on Cu(110),ANGEWANDTE CHEMIE, Issue 13 2010Matthew Forster In die Fußstapfen getreten: Racemisches (R,S) - Prolin bildet auf Cu(110) Reihen aus zufällig angeordneten chiralen Aminosäuren, was belegt, dass die Anordnung nicht durch die Molekülchiralität festgelegt wird. Vielmehr wird sie durch ein streng heterochirales Adsorptions-,Fußstapfen"-Templat bestimmt, in dem jede Adsorptionsposition von jedem der Enantiomere besetzt werden kann (siehe Bild), was eine ungeordnete zweidimensionale feste Lösung ergibt. [source] Degradation of Chlorocarbons Driven by Hydrodynamic CavitationCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 5 2007Z.-L. Wu Abstract To provide an efficient lab-scale device for the investigation of the degradation of organic pollutants driven by hydrodynamic cavitation, the degradation kinetics of chloroform and carbon tetrachloride and the increase of conductivity in aqueous solutions were measured. These are values which were not previously available. Under hydrodynamic cavitation conditions, the degradation kinetics for chlorocarbons was found to be pseudo first-order. Meanwhile, C-H and C-Cl bonds are broken, and Cl2, Cl., Cl, and other ions released can increase the conductivity and enhance the oxidation of KI in aqueous solutions. The upstream pressures of the orifice plate, the cavitation number, and the solution temperature have substantial effects on the degradation kinetics. A decreased cavitation number can result in more cavitation events and enhances the degradation of chlorocarbons and/or the oxidation of KI. A decrease in temperature is generally favorable to the cavitation chemistry. Organic products from the degradation of carbon tetrachloride and chloroform have demonstrated the formation and recombination of free radicals, e.g., CCl4, C2Cl4, and C2Cl6 are produced from the degradation of CHCl3. CHCl3 and C2Cl6 are produced from the degradation of CCl4. Both the chemical mechanism and the reaction kinetics of the degradation of chlorocarbons induced by hydrodynamic cavitation are consistent with those obtained from the acoustic cavitation. Therefore, the technology of hydrodynamic cavitation should be a good candidate for the removal of organic pollutants from water. [source] Entropy Effects in Atom Distribution and Electrochemical Properties of AuxPt1,x/Pt(111) Surface AlloysCHEMPHYSCHEM, Issue 7 2010Andreas Bergbreiter Abstract We report on the structural and electrochemical properties of AuxPt1,xsurface alloys prepared by Au vapour deposition onto Pt(111) followed by annealing to 1000 K. Driven by configurational entropy, Pt and Au atoms are distributed homogeneously over the surface. On the nm scale, however, atomically resolved scanning tunnelling microscopy images with chemical contrast reveal the formation of nm-sized Pt-rich and Au-rich aggregates, similar to the behaviour recently reported for PdxRu1,x/Ru(0001) [H. Hartmann, T. Diemant, A. Bergbreiter, J. Bansmann, H. E. Hoster, R. J. Behm, Surf. Sci. 2009, 603, 1439]. Based on the STM data, we determine the abundance of specific adsorption sites for different Au contents, and we derive effective pair interaction parameters that allow reproducing the lateral distribution in Monte Carlo simulations. Cyclic voltammograms of the surface alloys have many similarities with Pt(111). Had and OHad related features both decrease with increasing amount of Au. Both seem to adsorb only on Pt sites, but Had requires smaller ensembles of Pt atoms than OHad. The onset potential for Had -formation decreases with increasing Au content. This is can be explained by an effect of the Au atoms on the entropy of adsorption. [source] The Contribution of Chemoreflex Drives to Resting Breathing in ManEXPERIMENTAL PHYSIOLOGY, Issue 1 2001Safraaz Mahamed The contribution of automatic drives to breathing at rest, relative to behavioural drives such as ,wakefulness', has been a subject of debate. We measured the combined central and peripheral chemoreflex contribution to resting ventilation using a modified rebreathing method that included a prior hyperventilation and addition of oxygen to maintain isoxia at a PET,O2 (end-tidal partial pressure of oxygen) of 100 mmHg. During rebreathing, ventilation was unrelated to PET,CO2 (end-tidal partial pressure of carbon dioxide) in the hypocapnic range, but after a threshold PET,CO2 was exceeded, ventilation increased linearly with PET,CO2. We considered the sub-threshold ventilation to be an estimate of the behavioural drives to breathe (mean ± S.E.M. = 3.1 ± 0.5 l min,1), and compared it to ventilation at rest (mean ± S.E.M. = 9.1 ± 0.7 l min,1). The difference was significant (Student's paired t test, P < 0.001). We also considered the threshold PCO2 observed during rebreathing to be an estimate of the chemoreflex threshold at rest (mean ± S.E.M. = 42.0 ± 0.5 mmHg). However, PET,CO2 during rebreathing estimates mixed venous or tissue PCO2, whereas the resting PET,CO2 during resting breathing estimates Pa,CO2 (arterial partial pressure of carbon dioxide). The chemoreflex threshold measured during rebreathing was therefore reduced by the difference in PET,CO2 at rest and at the start of rebreathing (the plateau estimates the mixed venous PCO2 at rest) in order to make comparisons. The corrected chemoreflex thresholds (mean ± S.E.M. = 26.0 ± 0.9 mmHg) were significantly less (paired Student's t test, P < 0.001) than the resting PET,CO2 values (mean ± S.E.M. = 34.3 ± 0.5 mmHg). We conclude that both the behavioural and chemoreflex drives contribute to resting ventilation. [source] High-level distribution for the rapid production of robust telecoms software: comparing C++ and ERLANGCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2008J. H. Nyström Abstract Currently most distributed telecoms software is engineered using low- and mid-level distributed technologies, but there is a drive to use high-level distribution. This paper reports the first systematic comparison of a high-level distributed programming language in the context of substantial commercial products. Our research strategy is to reengineer some C++/CORBA telecoms applications in ERLANG, a high-level distributed language, and make comparative measurements. Investigating the potential advantages of the high-level ERLANG technology shows that two significant benefits are realized. Firstly, robust configurable systems are easily developed using the high-level constructs for fault tolerance and distribution. The ERLANG code exhibits resilience: sustaining throughput at extreme loads and automatically recovering when load drops; availability: remaining available despite repeated and multiple failures; dynamic reconfigurability: with throughput scaling near-linearly when resources are added or removed. Secondly, ERLANG delivers significant productivity and maintainability benefits: the ERLANG components are less than one-third of the size of their C++ counterparts. The productivity gains are attributed to specific language features, for example, high-level communication saves 22%, and automatic memory management saves 11%,compared with the C++ implementation. Investigating the feasibility of the high-level ERLANG technology demonstrates that it fulfils several essential requirements. The requisite distributed functionality is readily specified, even although control of low-level distributed coordination aspects is abrogated to the ERLANG implementation. At the expense of additional memory residency, excellent time performance is achieved, e.g. three times faster than the C++ implementation, due to ERLANG's lightweight processes. ERLANG interoperates at low cost with conventional technologies, allowing incremental reengineering of large distributed systems. The technology is available on the required hardware/operating system platforms, and is well supported. Copyright © 2007 John Wiley & Sons, Ltd. [source] Mechanisms of exercise-induced improvements in the contractile apparatus of the mammalian myocardiumACTA PHYSIOLOGICA, Issue 4 2010O. J. Kemi Abstract One of the main outcomes of aerobic endurance exercise training is the improved maximal oxygen uptake, and this is pivotal to the improved work capacity that follows the exercise training. Improved maximal oxygen uptake in turn is at least partly achieved because exercise training increases the ability of the myocardium to produce a greater cardiac output. In healthy subjects, this has been demonstrated repeatedly over many decades. It has recently emerged that this scenario may also be true under conditions of an initial myocardial dysfunction. For instance, myocardial improvements may still be observed after exercise training in post-myocardial infarction heart failure. In both health and disease, it is the changes that occur in the individual cardiomyocytes with respect to their ability to contract that by and large drive the exercise training-induced adaptation to the heart. Here, we review the evidence and the mechanisms by which exercise training induces beneficial changes in the mammalian myocardium, as obtained by means of experimental and clinical studies, and argue that these changes ultimately alter the function of the whole heart and contribute to the changes in whole-body function. [source] ECCD Experiments Using the Upgraded Launching System in Heliotron JCONTRIBUTIONS TO PLASMA PHYSICS, Issue 6-7 2010K. Nagasaki Abstract Electron cyclotron current drive (ECCD) experiments have been made in Heliotron J by using an upgraded EC launching system. A focused Gaussian beam is injected with the parallel refractive index, N||, ranging from -0.05 to 0.6. Ray tracing calculation shows that the EC power is more localized than that in the previous launching system. In the initial ECCD experiment, the EC injection angle has been successfully scanned as designed. Comparison between perpendicular and oblique launching experiments shows that for standard configuration, the EC current of 1 kA is driven at N|| , 0.3 in the Fisch-Boozer direction, and the bootstrap current flows up to 1 kA. A large increase in electron cyclotron emission (ECE) signals has been observed when the EC current was driven (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||