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Stronger Effects (stronger + effects)
Selected AbstractsEffects of plant invasions on the species richness of abandoned agricultural landECOGRAPHY, Issue 6 2001Scott J. Meiners While exotic plant invasions are thought to lead to declines in native species, the long-term impacts of such invasions on community structure are poorly known. Furthermore, it is unknown how exotic plant invasions compare to invasions by native species. We present data from 40 yr of continuous vegetation sampling of 10 fields released from agriculture to examine the effects of invasions on species richness. The effects of both exotic and native species invasions on species richness were largely driven by variations among fields with most species not significantly affecting species richness. However, invasion and dominance by the exotics Agropyron repens, Lonicera japonica. Rosa multiflora. Trifolium pratense and the native Solidago canadensis were associated with declines in richness. Invasions by exotic and native species during old field succession have similar effects on species richness with dominance by species of either group being associated with loss of species richness. Exotic species invasions tended to have stronger effects on richness than native invasions. No evidence was found of residual effects of invasions because the impact of the invasion disappeared with the decline of the invading population. When pooled across species, heavy invasion by exotic species resulted in greater loss o species richness than invasion by native species. Studies of invasion that utilize multiple sites must account for variability among sites. In our study, had we no included field as a factor we would have incorrectly concluded that invasion consistently resulted in changes in species richness. [source] Real-time monitoring of intracellular calcium dynamic mobilization of a single cardiomyocyte in a microfluidic chip pertaining to drug discoveryELECTROPHORESIS, Issue 24 2007Xiujun Li Abstract A microfluidic method for real-time quantitative measurement of cellular response pertaining to drug discovery is reported. This method is capable of multiple-step liquid delivery for measuring the drug response of a single cardiomyocyte, due to the improved cell retention by a newly designed chip. The chip, which consists of a cell-retention chamber with a weir structure, was fabricated just by a one-photomask microfabrication procedure followed by on-chip etching. This method differs from the conventional method, which uses two-mask photolithography to fabricate the microchannel (deep etch) and the weir structure (shallow etch). The dimensions of the weir structure have been predicted by a mathematical model, and confirmed by confocal microscopy. Using this microfluidic method, the dynamic [Ca2+]i mobilization in a single cardiomyocyte during its spontaneous contraction was quantified. Furthermore, we measured the cellular response of a cardiomyocyte on (i) a known cardiotonic agent (caffeine), (ii) a cardiotoxic chemotherapeutic drug (daunorubicin), and (iii) an herbal anticancer drug candidate , isoliquiritigenin (IQ) based on the fluorescent calcium measurement. It was found that IQ had produced a less pronounced effect on calcium mobilization of the cardiomyocytes whereas caffeine and daunorubicin had much stronger effects on the cells. These three experiments on cardiomyocytes pertaining to drug discovery were only possible after the improved cell retention provided by the new chip design (MV2) required for multiple-step real-time cellular analysis on a microchip, as compared with our old chip design (MV1). [source] Quantifying the relationship between soil organic carbon and soil physical properties using shrinkage modellingEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2009P. Boivin Summary Changes in soil organic carbon (SOC) may strongly affect soil structure and soil physical properties, which in turn may have feedback effects on the soil microbial activity and SOC dynamics. Such interactions are still not quantitatively described and accounted for in SOC dynamics modelling. The objective of this study was to test the hypothesis that soil shrinkage curve (ShC) analysis allows the establishment of close relationships between soil physical properties and SOC. We sampled a rice-cropped vertisol, a cambisol under conventional tillage and no-tillage and a restored cambisol. Soil samples were analysed for clay and SOC content, bulk volume, hydro-structural stability and plasma and structural pore volumes changes on the full water content range using ShC analysis. Although the soils behaved differently according to their constituents and history, changes in SOC linearly affected most of the soil physical properties, with stronger effects than changes in clay content. The observed effects of increasing SOC, such as increasing hydro-structural stability, specific bulk volume and water retention, agreed well with previously reported results. However, using ShC measurement and modelling allowed the observation of all these different effects simultaneously for small changes in SOC, and in a single measurement. Moreover, the relation between SOC changes and physical properties could be quantified. ShC analysis may, therefore, be used to account for the effect of changes in SOC on soil physical properties. [source] The role of light for fish,zooplankton,phytoplankton interactions during winter in shallow lakes , a climate change perspectiveFRESHWATER BIOLOGY, Issue 5 2009METTE ELISABETH BRAMM Summary 1.,Variations in the light regime can affect the availability and quality of food for zooplankton grazers as well as their exposure to fish predation. In northern lakes light is particularly low in winter and, with increasing warming, the northern limit of some present-day plankton communities may move further north and the plankton will thus receive less winter light. 2.,We followed the changes in the biomass and community structure of zooplankton and phytoplankton in a clear and a turbid shallow lake during winter (November,March) in enclosures both with and without fish and with four different light treatments (100%, 55%, 7% and <1% of incoming light). 3.,In both lakes total zooplankton biomass and chlorophyll- a were influenced by light availability and the presence of fish. Presence of fish irrespective of the light level led to low crustacean biomass, high rotifer biomass and changes in the life history of copepods. The strength of the fish effect on zooplankton biomass diminished with declining light and the effect of light was strongest in the presence of fish. 4.,When fish were present, reduced light led to a shift from rotifers to calanoid copepods in the clear lake and from rotifers to cyclopoid copepods in the turbid lake. Light affected the phytoplankton biomass and, to a lesser extent, the phytoplankton community composition and size. However, the fish effect on phytoplankton was overall weak. 5.,Our results from typical Danish shallow eutrophic lakes suggest that major changes in winter light conditions are needed in order to have a significant effect on the plankton community. The change in light occurring when such plankton communities move northwards in response to global warming will mostly be of modest importance for this lake type, at least for the rest of this century in an IPCC A2 scenario, while stronger effects may be observed in deep lakes. [source] Social Identification and Interpersonal Communication in Computer-Mediated Communication: What You Do Versus Who You Are in Virtual GroupsHUMAN COMMUNICATION RESEARCH, Issue 1 2009Zuoming Wang This study investigates the influence of interpersonal communication and intergroup identification on members' evaluations of computer-mediated groups. Participants (N= 256) in 64 four-person groups interacted through synchronous computer chat. Subgroup assignments to minimal groups instilled significantly greater in-group versus out-group identification. One member in each group was instructed to exhibit interpersonally likable or dislikable behavior. Analysis revealed that confederates acting likably were more attractive than those acting dislikably regardless of their in-group or out-group status. Further results indicated that interpersonal behavior interacted with subgroup membership on identification shifts following online discussions. Interpersonal dynamics generally provided stronger effects on members in virtual groups than did intergroup dynamics, in contrast to predictions from previous applications of social identification to computer-mediated communication. Résumé L,identification sociale et la communication interpersonnelle dans la communication par ordinateur : Ce que vous faites et qui vous êtes dans les groupes virtuels Cette étude examine l'influence de la communication interpersonnelle et de l,identification intergroupe sur les évaluations que font les membres des groupes électroniques. Les participants (N= 256), divisés en 64 groupes de quatre personnes, ont interagi par le biais de clavardage (conversation électronique) en temps réel. L'assignation à des sous-groupes a produit une identification intragroupe beaucoup plus grande qu,une identification hors-groupe. Des instructions furent données à un membre de chaque groupe d'afficher des comportements interpersonnels agréables ou désagréables. L,analyse révèle que les collaborateurs agissant de façon agréable étaient plus attrayants que ceux agissant de façon désagréable et ce, indépendamment de leur statut intragroupe ou hors-groupe. Des résultats supplémentaires indiquent que le comportement interpersonnel et l'appartenance au sous-groupe ont joué sur les changements d,identification qui ont suivi les discussions en ligne. La dynamique interpersonnelle a généralement eu des effets plus forts sur les membres des groupes virtuels que la dynamique intergroupe, contrairement aux prédictions des applications précédentes de l'identification sociale à la communication par ordinateur. Abstract Soziale Identifikation und interpersonale Kommunikation in computervermittelter Kommunikation: Was du machst vs. Wer du bist in virtuellen Gruppen Diese Studie untersucht den Einfluss von interpersonaler Kommunikation und Gruppenidentifikation auf die Bewertung von computervermittelten Gruppen durch ihre Mitglieder. Die Teilnehmer (N= 256) in 64 4-Personen Gruppen interagierten in synchronen Computer-Chats. Gruppenaufgaben für Untergruppen bewirkte signifikant stärkere Identifikation in der Gruppe und nach außen. In jeder Gruppe wurde ein Teilnehmer instruiert, interpersonal angenehmes oder unangenehmes Verhalten an den Tag zu legen. Die Analyse zeigte, dass die instruierten Teilnehmer, die angenehm agierten, attraktiver wahrgenommen wurden, als die, die die unangenehm agierten, unabhängig von ihrem Status in oder außerhalb der Gruppe. Weitere Ergebnisse zeigen, dass interpersonales Verhaltes mit der Mitgliedschaft in Untergruppen bezüglich der Identifikationsverschiebung auf Online-Diskussionen folgend interagierte. Im Gegensatz zu Annahmen aus früheren Anwendungen sozialer Identifikation auf computervermittelte Kommunikation, zeigten interpersonale Dynamiken allgemein stärkere Effekte auf die Mitglieder in virtuellen Gruppen als auf die Gruppendynamik. Resumen La identificación Social y la Comunicación Interpersonal en la Comunicación Mediada por la Computadora: Lo Que Haces Versus Quién Eres en los Grupos Virtuales Este estudio investiga la influencia de la comunicación interpersonal y la identificación intergrupal en las evaluaciones de los miembros de grupos mediados por la computadora. Los participantes (N= 256) en 64 grupos de 4 personas interactuaron asincrónicamente a través de la computadora en un salón de charla. Las tareas de subgrupos para grupos mínimos inculcaron una identificación significativamente mayor con el grupo de pertenencia versus el grupo excluyente. Un miembro de cada grupo fue instruido para exhibir comportamientos interpersonales agradables y desagradables. El análisis reveló que los miembros de los grupos que actuaban en forma agradable fueron más atractivos que los que actuaban en forma desagradable a pesar de su estatus de grupo de pertenencia o excluyente. Más resultados indicaron que el comportamiento interpersonal interactuó con la membrecía del subgrupo en los cambios de identificación que siguieron a las discusiones online. Las dinámicas interpersonales proveyeron generalmente de efectos más fuertes sobre los miembros de grupos virtuales que sobre las dinámicas intergrupales, en contraste con las predicciones de previas aplicaciones de la identificación social de la comunicación mediada por la computadora. ZhaiYao Yo yak [source] Black and white and read all over: Race differences in reactions to recruitment Web sitesHUMAN RESOURCE MANAGEMENT, Issue 2 2008Caren B. Goldberg Based on signaling theory, this study examines the impact of Web-site design and content characteristics on applicants' intentions to pursue employment, the mediating effects of engagement with the Web site and attitude toward the organization, and the moderating effects of applicant race on these relationships. The design characteristics of ease of use and usefulness impact attraction indirectly through Web-site engagement and attitude toward the organization. Further, Web sites' parasocial interaction (allowance for two-way communication) predicts intentions to pursue both directly and indirectly through engagement and attitude toward the organization. Unexpectedly, diversity statements did not impact attraction in the full sample. Multigroup analyses revealed that many of the paths between the predictors of parasocial interaction and (to a lesser extent) diversity statements and the outcomes differed by race, with stronger effects observed for blacks than whites. Theoretical and practical implications are discussed. © 2008 Wiley Periodicals, Inc. [source] Interrelations between maternal smoking during pregnancy, birth weight and sociodemographic factors in the prediction of early cognitive abilitiesINFANT AND CHILD DEVELOPMENT, Issue 6 2006S. C. J. Huijbregts Abstract Maternal prenatal smoking, birth weight and sociodemographic factors were investigated in relation to cognitive abilities of 1544 children (aged 3.5 years) participating in the Québec Longitudinal Study of Children's Development. The Peabody Picture Vocabulary Test (PPVT) was used to assess verbal ability, the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) block design test to assess visuospatial ability, and the Visually Cued Recall (VCR) task to assess short-term memory. Prenatal smoking was related to performance on the WPPSI-R, the PPVT, and the VCR, although it did not independently predict any cognitive ability after maternal education was taken into account. Birth weight was a more robust predictor of all outcome measures and independently predicted VCR-performance. Birth weight interacted significantly with family income and maternal education in predicting visuospatial ability, indicating a greater influence of birth weight under relatively poor socio-economic conditions. Parenting and family functioning mediated associations between maternal education/family income and cognitive task performance under different birth weight conditions, although there were indications for stronger effects under relatively low birth weight. We conclude that investigations of moderating and mediating effects can provide insights into which children are most at risk of cognitive impairment and might benefit most from interventions. Copyright © 2006 John Wiley & Sons, Ltd. [source] Towards a multi-foci approach to workplace aggression: A meta-analytic review of outcomes from different perpetrators,JOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 1 2010M. Sandy Hershcovis Using meta-analysis, we compare three attitudinal outcomes (i.e., job satisfaction, affective commitment, and turnover intent), three behavioral outcomes (i.e., interpersonal deviance, organizational deviance, and work performance), and four health-related outcomes (i.e., general health, depression, emotional exhaustion, and physical well being) of workplace aggression from three different sources: Supervisors, co-workers, and outsiders. Results from 66 samples show that supervisor aggression has the strongest adverse effects across the attitudinal and behavioral outcomes. Co-worker aggression had stronger effects than outsider aggression on the attitudinal and behavioral outcomes, whereas there was no significant difference between supervisor, co-worker, and outsider aggression for the majority of the health-related outcomes. These results have implications for how workplace aggression is conceptualized and measured, and we propose new research questions that emphasize a multi-foci approach. Copyright © 2009 John Wiley & Sons, Ltd. [source] The mediating role of overall fairness and the moderating role of trust certainty in justice,criteria relationships: the formation and use of fairness heuristics in the workplaceJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 8 2009David A. Jones Theory suggests that perceptions of overall fairness play an important role in the justice judgment process, yet overall fairness is insufficiently studied. We derived hypotheses from fairness heuristic theory, which proposes that perceptions of overall fairness are influenced by different types of justice, are more proximal predictors of responses than specific justice types, and are used to infer trust when trust certainty is low. Results from Study 1 (N,=,1340) showed that employees' perceptions of overall fairness in relation to a senior management team mediated the relationships between specific types of justice and employee outcomes (e.g., affective commitment). In Study 2 (N,=,881), these mediated effects were replicated and trust certainty moderated the effect of overall fairness on trust as hypothesized. Study 2 also showed that, relative to procedural and informational justice, distributive and interpersonal justice had stronger effects on overall fairness. To explore how the organizational context may have influenced these findings, we performed qualitative analyses in Study 3 (N,=,268). Results suggested that, consistent with the quantitative findings from Study 2, some types of justice were more salient than others. We discuss the implications of our findings for theory, research, and practice. Copyright © 2008 John Wiley & Sons, Ltd. [source] EFFECT OF COPPER ON ALGAL COMMUNITIES FROM OLIGOTROPHIC CALCAREOUS STREAMS1JOURNAL OF PHYCOLOGY, Issue 2 2002Helena Guasch Two sets of experiments were done to quantify the effects of chronic copper exposure on natural peri- phyton in a nonpolluted calcareous river. The results of short-term (up to 6 h exposure) experiments corroborated the significance of pH on copper toxicity. Copper toxicity increased when pH was reduced from 8.6 to 7.7, and this was related to the effect of pH on copper speciation (free copper concentration increased from 0.2% to 2.3% of total copper). Longer term experiments demonstrated that periphyton communities exposed to copper under pH variation (8.2,8.6) were already affected at 10 ,g·L,1 (20,80 ng·L,1 Cu2+) after 12 days of exposure. Copper exposure caused stronger effects on structural (algal biomass and community structure) than on functional (photosynthetic efficiency) parameters of peri- phyton. Changes in community composition included the enhancement of some taxa (Gomphonema gracile), the inhibition of others (Fragilaria capucina and Phormidium sp.), and the appearance of filament malformations (Mougeotia sp.). The results of our study demonstrated that several weeks of exposure to copper (10,20 ,g·L,1) were sufficient to cause chronic changes in the periphyton of oligotrophic calcareous rivers. This degree of copper pollution can be commonly found in the Mediterranean region as a result of agricultural practices and farming activities. [source] The Evaluation of School-Based Violence Prevention Programs: A Meta-Analysis,JOURNAL OF SCHOOL HEALTH, Issue 9 2008Hyoun-Kyoung Park-Higgerson PhD ABSTRACT Background:, Youth violence and related aggressive behaviors have become serious public health issues with physical, economic, social, and psychological impacts and consequences. This study identified and evaluated the characteristics of successful school-based violence prevention programs. Methods:, Twenty-six randomized controlled trial (RCT), school-based studies that were designed to reduce externalizing, aggressive, and violent behavior between the 1st and 11th grades were analyzed for assessing the effects of 5 program characteristics by comparing results of intervention groups to control groups (no intervention) after intervention using a meta-analysis. Electronic databases and bibliographies were systematically searched, and a standardized mean difference was used for analysis. Results:, There was no significant difference between interventions, although programs that used non,theory-based interventions, focused on at-risk and older children, and employed intervention specialists had slightly stronger effects in reducing aggression and violence. Interventions using a single approach had a mild positive effect on decreasing aggressive and violent behavior (effect size =,0.15, 95% CI =,0.29 to ,0.02, p = .03). Conclusions:, Unlike previous individual study findings, this meta-analysis did not find any differential effects for 4 of the 5 program characteristics. In addition, the significant effect noted was contrary to expectation, exemplifying the complexity of identifying effective program strategies. This study adds to the current literature by assessing the program characteristics of RCT studies in an effort to determine what factors may affect school-based violence prevention program success. [source] Comparison of effects of in vivo nitrogen dioxide exposure starting from different periods on alveolar macrophage activity, assessed by a chemiluminescence technique in Brown-Norway ratsLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2006Takashi Kumae Abstract Nitrogen dioxide (NO2) has been extensively studied for its immune modulating effects on pulmonary cells. Alveolar macrophages (AMs) play an important role in pulmonary immunity. The Brown-Norway (BN) rat has been studied as a high-risk model of allergic diseases. In this study, BN rats were exposed to NO2 from the embryonic or weanling period (EP or WP, respectively). To evaluate the effects of NO2 exposure on pulmonary immunity, the activity levels of rat AMs were assessed as reactive oxygen species-generating capacity, measured by a chemiluminescence (CL) technique, and as cytokine-producing ability. Except for 0.2 ppm of NO2 exposure, the CL responses of AMs obtained from the WP group at 12 weeks old were suppressed significantly. Changes of the cytokine-producing levels suggest that inflammatory reactions are terminated at 12 weeks in the EP group. Correlations between the CL responses and the cytokine levels reveal that NO2 exposure may modulate the direction of AM activation. The CL technique is thought to be useful to evaluate changes in AM activity. In this study, the results suggest that, using the high-risk model of allergic diseases, NO2 exposure from the weanling period has stronger effects on AM activity.Copyright © 2006 John Wiley & Sons, Ltd. [source] RACIAL DIFFERENCES IN EMPLOYEE RETENTION: ARE DIVERSITY CLIMATE PERCEPTIONS THE KEY?PERSONNEL PSYCHOLOGY, Issue 1 2007PATRICK F. McKAY Given considerable racial differences in voluntary turnover (Bureau of Labor Statistics, 2006, Table 28), the present study examined the influence of diversity climate perceptions on turnover intentions among managerial employees in a national retail organization. The authors hypothesized that pro-diversity work climate perceptions would correlate most negatively with turnover intentions among Blacks, followed in order of strength by Hispanics and Whites (Hypothesis 1), and that organizational commitment would mediate these interactive effects of race and diversity climate perceptions on turnover intentions (Hypothesis 2). Results from a sample of 5,370 managers partially supported both hypotheses, as findings were strongest among Blacks. Contrary to the hypotheses, however, White men and women exhibited slightly stronger effects than Hispanic personnel. [source] Antiproliferative effects of different plant parts of Panax notoginseng on SW480 human colorectal cancer cellsPHYTOTHERAPY RESEARCH, Issue 1 2009Chong-Zhi Wang Abstract The chemical constituents and antiproliferative effects on SW480 human colorectal cancer cells of different plant parts of P. notoginseng were evaluated. The contents of saponins in extracts from root, rhizome, flower and berry of P. notoginseng were determined using high performance liquid chromatography. The contents and proportions of saponins were different among the four plant parts. Using the cell counting method, the antiproliferative effects were evaluated and the results indicated all four extracts, at 0.05,1.0 mg/mL, showed concentration-related antiproliferative effects on the cancer cells. The flower extract had stronger effects compared with the other three extracts; at 1.0 mg/mL, it inhibited the cell growth by 93.1% (p < 0.01). The antiproliferative effects of major saponins in notoginseng, notoginsenoside R1, ginsenosides Rb1, Rb3 and Rg1, were also evaluated, and the observed effects of major constituents support the pharmacological activities of extracts. The effects of notoginseng extracts on cell cycle and apoptosis of SW480 cells were determined using flow cytometry. Notoginseng extract can arrest the cells in S and G2/M phases. Remarkably apoptosis induction activities of notoginseng extracts were observed with the flower extract possessing the most potent effect, supporting the antiproliferative effect. Copyright © 2008 John Wiley & Sons, Ltd. [source] Rough Terrain: Spatial Variation in Campaign Contributing and VolunteerismAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 1 2010Wendy K. Tam Cho We examine spatial patterns of mass political participation in the form of volunteering and donating to a major statewide election campaign. While these forms of participation are predictably associated with the political and socioeconomic characteristics of the precincts in which the participants reside, we find that these statistical relationships are spatially nonstationary. High-income neighborhoods, for example, are associated with stronger effects on participation at some locations more than at others. By using geographically weighted regression (GWR) to specify local regression parameters, we are able to capture the heterogeneity of contextual processes that generate the geographically uneven flow of volunteers and contributors into a political campaign. Since spatial nonstationarity may well be a rule rather than an exception in the study of many political phenomena, social scientific analyses should be mindful that relationships may vary by location. [source] Corporate Political Contributions and Stock ReturnsTHE JOURNAL OF FINANCE, Issue 2 2010MICHAEL J. COOPER ABSTRACT We develop a new and comprehensive database of firm-level contributions to U.S. political campaigns from 1979 to 2004. We construct variables that measure the extent of firm support for candidates. We find that these measures are positively and significantly correlated with the cross-section of future returns. The effect is strongest for firms that support a greater number of candidates that hold office in the same state that the firm is based. In addition, there are stronger effects for firms whose contributions are slanted toward House candidates and Democrats. [source] Susceptibility to postidentification feedback is affected by source credibilityAPPLIED COGNITIVE PSYCHOLOGY, Issue 4 2009Elin M. Skagerberg How much a person is affected by postidentification feedback is dependent on the credibility of the person giving the feedback. Seven hundred and ninety participants across three experiments viewed a crime video, made judgments from a line-up, were provided with co-witness and/or outcome feedback (from police officers [high credibility] or children [low credibility]), and answered testimony-relevant questions (e.g. How good a view did you get of the person in the video?). The aim was to find out how high versus low credibility co-witness feedback affects a witness' retrospective judgments (Experiment 1) as well as estimations of these co-witnesses' judgments (Experiment 2). Experiment 1 showed that the feedback effect was only observed when the co-witness responses were attributed to a high credibility source. Experiment 2 showed that high credibility co-witnesses were estimated to score higher on the testimony-relevant questions as compared to low credibility co-witnesses. Experiment 3 showed that outcome feedback (e.g. ,you identified the suspect') produces stronger effects on testimony-relevant questions than co-witness feedback. The implications of these findings are that when postidentification feedback is present, it is important to determine the source of this feedback. Copyright © 2008 John Wiley & Sons, Ltd. [source] Smoking increases rheumatoid arthritis susceptibility in individuals carrying the HLA,DRB1 shared epitope, regardless of rheumatoid factor or anti,cyclic citrullinated peptide antibody statusARTHRITIS & RHEUMATISM, Issue 2 2010So-Young Bang Objective Smoking is associated with rheumatoid arthritis (RA) in individuals with the HLA,DRB1 shared epitope (SE). SE alleles have been shown to be predominantly associated with anti,cyclic citrullinated peptide (anti-CCP),positive RA. These risk factors have not been identified for anti-CCP,negative RA. The aim of this study was to investigate whether SE-containing HLA,DRB1 alleles, smoking, or the combination of these factors contributes to the development of RA, depending on the presence or absence of serologic markers, in a Korean population. Methods All of the patients with RA (n =1,482) and all of the control subjects (n = 1,119) were Korean. Four-digit HLA,DRB1 typing was performed by a conventional polymerase chain reaction,sequence-based typing method. Information about smoking history was obtained through a questionnaire. The patients with RA were tested for anti-CCP antibodies and rheumatoid factor (RF). Results The SE alleles had significant effects on anti-CCP antibody and RF formation. The DRB1*0901 allele was associated with the presence of anti-CCP antibodies (odds ratio [OR] 2.49) and RF (OR 2.09). SE alleles and smoking were associated with both anti-CCP,positive and anti-CCP,negative RA. The combination of smoking and double copies of the SE allele increased the risk of anti-CCP,positive RA 36.11-fold and increased the risk of anti-CCP,negative RA 12.29-fold, compared with the risk among nonsmokers not carrying SE alleles. Interactions between SE alleles and smoking were observed for both anti-CCP,positive and RF-positive RA, although the associations of RF-positive RA could be consequences of the underlying anti-CCP antibody status. Conclusion We demonstrated that the combination of SE alleles and smoking is associated with RA susceptibility regardless of anti-CCP antibody or RF status, but that the combination shows stronger effects in anti-CCP,positive/RF-positive patients with RA than in anti-CCP,negative/RF-negative patients with RA. The SE,smoking interactions were present in anti-CCP,positive and RF-positive RA. [source] Sociopsychological profiles of students that leave the ingroup or engage in social competitionASIAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 1 2009Agustin Echebarria-Echabe We present a study of the sociopsychological profiles of students who are disposed to engage in social competition on behalf of ingroup interests. Five predictors were selected: the advantageous or unfavourable context for ingroup interests, group identification, meritocracy, just-world beliefs, and social dominance orientation. It was found that those students who were prepared to invest personal resources on behalf of ingroup interests were characterized by a strong group identification and middle or low scores in the meritocracy and social dominance orientation. In contrast, students with the lowest disposition to social competition were defined by their low identification and/or middle-high scores in the meritocracy and social dominance orientation. Against our expectation, the manipulation of the favourable versus unfavourable situation of the ingroup did not have a significant influence. In order of their importance, the variables that showed stronger effects were group identification, followed by meritocracy, social dominance orientation, and world-just beliefs. [source] Testing for Temporal Asymmetry in the Price-Volume RelationshipBULLETIN OF ECONOMIC RESEARCH, Issue 4 2003Imad A. Moosa G14; C22 Abstract This paper presents some evidence for the presence of temporal asymmetry in the price-volume relationship in the crude oil futures market. By using threshold models we show that there is bidirectional causality between volume and prices, whereas the conventional model that assumes symmetry can only detect unidirectional causality. The results also show that the price-volume relationship is asymmetric, in the sense that negative price and volume changes have stronger effects (on each other) than positive changes. Some explanations for asymmetry in the price-volume relationship are suggested. [source] Classroom and Developmental Differences in a Path Model of Teacher Expectancy EffectsCHILD DEVELOPMENT, Issue 5 2001Margaret R. Kuklinski A path model of teacher expectancy effects was evaluated in a sample of 376 first- through fifth-grade urban elementary school children. The roles of two moderators (classroom perceived differential treatment environment and developmental differences) and one mediator (children's self-expectations) of teacher expectancy effects on children's year-end achievement were examined. Significant differences in effects and effect sizes are presented. Both classroom environment (high versus low in differential treatment, as seen through children's eyes) and developmental differences moderated the strength of teacher expectancy effects. Generally, stronger effects were found in classrooms in which expectancy-related cues were more salient to children, but developmental differences moderated which effect was most pronounced. A significant age-related decline in direct effects on ending achievement was interpreted as evidence that teacher expectations may tend to magnify achievement differences in the early grades, but serve to sustain them in later grades. Support for indirect effects (teacher expectations , children's self-expectations , ending achievement) was limited to upper elementary grade classrooms perceived as high in differential treatment. In contrast to prior research that emphasized small effect sizes, the present analyses document several instances of moderate effects, primarily in classrooms in which expectancy-related messages were most salient to children. These results underscore the importance of explicit attention to the inclusion of moderators, mediators, and multiple outcomes in efforts to understand teacher expectancy effects. [source] Low socioeconomic status as a risk factor for asthma, rhinitis and sensitization at 4 years in a birth cohortCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2005C. Almqvist Summary Background The relation between socioeconomic status and allergic diseases in childhood is controversial. Some studies have proposed childhood asthma to be more common in families with low socioeconomic status, while sensitization to airborne allergens seems to be more frequent in individuals with higher socioeconomic status in childhood. Objective To assess the relation between socioeconomic status and asthma, rhinitis and sensitization in an unselected prospective birth cohort. Methods Four thousand and eighty-nine families with children born 1994,1996 in predefined areas of Stockholm answered questionnaires on environmental factors, socioeconomic status (parental occupation), and symptoms of allergic disease at birth, 1, 2 and 4 years of age. Blood samples taken at 4 years from 2614 children were analysed for specific IgE to common airborne and food allergens. Odds ratios (OR) and 95% confidence intervals (CI) for various outcomes in relation to socioeconomic status were estimated with a multiple logistic regression model, adjusting for potential confounders such as heredity for allergic diseases, maternal smoking, short duration of breastfeeding and house construction. Results There was a decreasing risk of asthma and rhinitis with increasing socioeconomic status. The OR for asthma was 0.33 (95% CI 0.17,0.66) and for rhinitis 0.50 (0.32,0.79) comparing the highest and the lowest socioeconomic groups, with a tendency to stronger effects in those with heredity for allergic disease. The risk of sensitization to food allergens also decreased with increasing socioeconomic status; OR 0.65 (0.41,1.02) in the highest socioeconomic group (Ptrend=0.03), which was not clearly seen for airborne allergens. Conclusion Asthma, rhinitis and sensitization is more common in lower than in higher socioeconomic groups after adjustment for traditional risk factors. This may be related to additional uncontrolled differences in life style and environmental exposures between the groups, and calls for further studies. [source] | |||||||||||||||||||||||||