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Different Measures (different + measure)
Kinds of Different Measures Selected AbstractsComparing Structural Equation Models That Use Different Measures of the Level of Response to AlcoholALCOHOLISM, Issue 5 2010Marc A. Schuckit Background:, The two measures of a low level of response (LR) to alcohol, an alcohol challenge and the retrospective Self-Report of the Effects of Alcohol questionnaire (SRE), each identify individuals at high risk for heavy drinking and alcohol problems. These measures also perform similarly in identifying subjects with unique functional brain imaging characteristics. However, few data are available regarding whether alcohol challenge-based and SRE-based LRs operate similarly in structural equation models (SEMs) that search for characteristics, which help to mediate how LR impacts alcohol outcomes. Methods:, Two hundred and ninety-four men from the San Diego Prospective Study were evaluated for their LR to alcohol using alcohol challenges at ,age 20. At ,age 35, the same subjects filled out the SRE regarding the number of drinks needed for effects 15 to 20 years earlier. The two different LR scores for these men were used in SEM analyses evaluating how LR relates to future heavy drinking and to drinking in peers (PEER), alcohol expectancies (EXPECT), and drinking to cope (COPE) as potential mediators of the LR to drinking pattern (ALCOUT) relationships. Results:, While the 2 LR measures that were determined 15 years apart related to each other at a modest level (r = 0.17, p < 0.01), the SEM results were similar regardless of the LR source. In both alcohol challenge-based and SRE-based LR models, LR related directly to ALCOUT, with partial mediation from PEER and COPE, but not through EXPECT in these 35-year-old men. Conclusions:, Consistent with the >60% overlap in prediction of outcomes for the 2 LR measures, and with results from functional brain imaging, alcohol challenge- and SRE-based LR values operated similarly in SEM models in these men. [source] Different measures of risk perceptions yield different patterns of interaction for combinations of hazards: smoking, family history and cardiac eventsJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 5 2004David P. French Abstract Some combinations of hazards yield disease rates greater than would be expected from the risk attributable to each hazard in isolation. However, perceptions are often more consistent with the combined risk being seen as less than the sum of the individual factors, raising concerns over the validity of some measures of risk perception. Here, 249 adults estimated the risk of cardiac events for four hypothetical men, described as having high or low levels of smoking and family history of heart disease. Three distinct measures were used. A 9-point scale produced a strong sub-additive interaction, a 101-point scale produced a weaker sub-additive interaction, and an unbounded scale produced no interaction. In this study, as in all previous research, scales with relatively few points (here a 9-point scale) yield sub-additive interactions. Given the consistency of results yielded by such scales, irrespective of context, it is concluded that these scales are not valid for perceptions of multiple risk factors. Copyright © 2004 John Wiley & Sons, Ltd. [source] Does Monetary Policy Have Asymmetric Effects on Stock Returns?JOURNAL OF MONEY, CREDIT AND BANKING, Issue 2-3 2007SHIU-SHENG CHEN monetary policy; stock returns; Markov-switching This paper investigates whether monetary policy has asymmetric effects on stock returns using Markov-switching models. Different measures of a monetary policy stance are adopted. Empirical evidence from monthly returns on the Standard & Poor's 500 price index suggests that monetary policy has larger effects on stock returns in bear markets. Furthermore, it is shown that a contractionary monetary policy leads to a higher probability of switching to the bear-market regime. [source] Comparing Democrats and Republicans on Intrinsic and Extrinsic ValuesJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 3 2009Kennon M. Sheldon Although claimed differences in values have played a prominent role in recent U.S. politics, the value systems of typical Republicans and Democrats have not been evaluated within a relevant dimensional framework. In 4 studies, party members were compared on extrinsic (money, popularity, image) and intrinsic (intimacy, helping, growth) values. Republicans were consistently higher on extrinsic relative to intrinsic values, a pattern suggested by past research to be personally and socially problematic. In Study 4, Republicans were also lower in a different measure of prosocial values, derived from social-dilemma research. All studies found an interaction such that only nonreligious Republicans were lower than Democrats on the intrinsic value of helping needy others. Implications for contemporary political discourse are discussed. [source] Susceptibility of Common and Rare Plant Species to the Genetic Consequences of Habitat FragmentationCONSERVATION BIOLOGY, Issue 3 2007OLIVIER HONNAY diversidad genética; endogamia; fragmentación de hábitat; sistema reproductivo; tamaño poblacional Abstract:,Small plant populations are more prone to extinction due to the loss of genetic variation through random genetic drift, increased selfing, and mating among related individuals. To date, most researchers dealing with genetic erosion in fragmented plant populations have focused on threatened or rare species. We raise the question whether common plant species are as susceptible to habitat fragmentation as rare species. We conducted a formal meta-analysis of habitat fragmentation studies that reported both population size and population genetic diversity. We estimated the overall weighted mean and variance of the correlation coefficients among four different measures of genetic diversity and plant population size. We then tested whether rarity, mating system, and plant longevity are potential moderators of the relationship between population size and genetic diversity. Mean gene diversity, percent polymorphic loci, and allelic richness across studies were positively and highly significantly correlated with population size, whereas no significant relationship was found between population size and the inbreeding coefficient. Genetic diversity of self-compatible species was less affected by decreasing population size than that of obligate outcrossing and self-compatible but mainly outcrossing species. Longevity did not affect the population genetic response to fragmentation. Our most important finding, however, was that common species were as, or more, susceptible to the population genetic consequences of habitat fragmentation than rare species, even when historically or naturally rare species were excluded from the analysis. These results are dramatic in that many more plant species than previously assumed may be vulnerable to genetic erosion and loss of genetic diversity as a result of ongoing fragmentation processes. This implies that many fragmented habitats have become unable to support plant populations that are large enough to maintain a mutation-drift balance and that occupied habitat fragments have become too isolated to allow sufficient gene flow to enable replenishment of lost alleles. Resumen:,Las poblaciones pequeñas de plantas son más propensas a la extinción debido a la pérdida de variación genética por medio de la deriva génica aleatoria, el incremento de autogamia y la reproducción entre individuos emparentados. A la fecha, la mayoría de los investigadores que trabajan con erosión genética en poblaciones fragmentadas de plantas se han enfocado en las especies amenazadas o raras. Cuestionamos si las especies de plantas comunes son tan susceptibles a la fragmentación del hábitat como las especies raras. Realizamos un meta análisis formal de estudios de fragmentación que reportaron tanto tamaño poblacional como diversidad genética. Estimamos la media general ponderada y la varianza de los coeficientes de correlación entre cuatro medidas de diversidad genética y de tamaño poblacional de las plantas. Posteriormente probamos si la rareza, el sistema reproductivo y la longevidad de la planta son moderadores potenciales de la relación entre el tamaño poblacional y la diversidad genética. La diversidad genética promedio, el porcentaje de loci polimórficos y la riqueza alélica en los estudios tuvieron una correlación positiva y altamente significativa con el tamaño poblacional, mientras que no encontramos relación significativa entre el tamaño poblacional y el coeficiente de endogamia. La diversidad genética de especies auto compatibles fue menos afectada por la reducción en el tamaño poblacional que la de especies exogámicas obligadas y especies auto compatibles, pero principalmente exogámicas. La longevidad no afectó la respuesta genética de la población a la fragmentación. Sin embargo, nuestro hallazgo más importante fue que las especies comunes fueron tan, o más, susceptibles a las consecuencias genéticas de la fragmentación del hábitat que las especies raras, aun cuando las especies histórica o naturalmente raras fueron excluidas del análisis. Estos resultados son dramáticos porque muchas especies más pueden ser vulnerables a la erosión genética y a la pérdida de diversidad genética como consecuencia de los procesos de fragmentación que lo se asumía previamente. Esto implica que muchos hábitats fragmentados han perdido la capacidad para soportar poblaciones de plantas lo suficientemente grandes para mantener un equilibrio mutación-deriva y que los fragmentos de hábitat ocupados están tan aislados que el flujo génico es insuficiente para permitir la reposición de alelos perdidos. [source] Why do Employment Rates Differ Across the Regions of Britain?ECONOMIC OUTLOOK, Issue 5 2004Article first published online: 29 OCT 200 Both unemployment and non-employment in Great Britain fell steadily after 1993. The ratio of jobs to the working age population , the employment rate , rose. But the increasing regional dispersion of employment rates remains a puzzle. By 2000,01, this dispersion was close to its 1974 and 1985 peak levels, though it has narrowed since 2001. This paper by John Muellbauer & Gavin Cameron1 examines this puzzle in the context of different measures of the employment rate and examines what we know and what we do not know about what drives relative employment rates across the British regions. It summarises the findings from an econometric study and examines the outlook for relative employment across the British regions. [source] A CROSS-COUNTRY ANALYSIS OF EXPORT PRICES IN OECD COUNTRIESECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 4 2006ABBAS VALADKHANI This article distinguishes the extent to which export price variation consists of global versus country-specific changes for fourteen OECD countries. We find that sharp changes in global export prices are evidently becoming more important for many of the OECD countries over the last twenty-five years as compared with the previous twenty-five year period. The article also finds that, by a number of different measures, whilst Australia's export price growth has apparently become more highly associated with world export prices in recent years, it nonetheless continues to have one of the more volatile set of export prices among OECD countries. [source] Does Entrepreneurship Capital Matter?ENTREPRENEURSHIP THEORY AND PRACTICE, Issue 5 2004David B. Audretsch Economics has identified three types of capital as the drivers of economic growth,physical capital, human capital, and knowledge capital. This article introduces the concept of entrepreneurship capital and suggests that it is also an important factor shaping the economic performance of an economy. We define entrepreneurship capital as those factors influencing and shaping an economy's milieu of agents in such a way as to be conducive to the creation of new firms. The hypothesis that entrepreneurship capital is positively linked to economic growth is then tested by examining the relationship between several different measures of entrepreneurship capital and regional economic performance, measured as per-capita income for Germany. The empirical evidence suggests that there is indeed a positive link between entrepreneurship capital and regional economic performance. These results suggest a new direction for public policy that focuses on instruments to enhance entrepreneurship capital. [source] REVIEW: Understanding the construct of impulsivity and its relationship to alcohol use disordersADDICTION BIOLOGY, Issue 2 2010Danielle M. Dick ABSTRACT There are well-established links between impulsivity and alcohol use in humans and other model organisms; however, the etiological nature of these associations remains unclear. This is likely due, in part, to the heterogeneous nature of the construct of impulsivity. Many different measures of impulsivity have been employed in human studies, using both questionnaire and laboratory-based tasks. Animal studies also use multiple tasks to assess the construct of impulsivity. In both human and animal studies, different measures of impulsivity often show little correlation and are differentially related to outcome, suggesting that the impulsivity construct may actually consist of a number of more homogeneous (and potentially more meaningful) subfacets. Here, we provide an overview of the different measures of impulsivity used across human and animal studies, evidence that the construct of impulsivity may be better studied in the context of more meaningful subfacets, and recommendations for how research in this direction may provide for better consilience between human and animal studies of the connection between impulsivity and alcohol use. [source] REVIEW: Impulsivity as a determinant and consequence of drug use: a review of underlying processesADDICTION BIOLOGY, Issue 1 2009Harriet De Wit ABSTRACT Impulsive behaviors are closely linked to drug use and abuse, both as contributors to use and as consequences of use. Trait impulsivity is an important determinant of drug use during development, and in adults momentary ,state' increases in impulsive behavior may increase the likelihood of drug use, especially in individuals attempting to abstain. Conversely, acute and chronic effects of drug use may increase impulsive behaviors, which may in turn facilitate further drug use. However, these effects depend on the behavioral measure used to assess impulsivity. This article reviews data from controlled studies investigating different measures of impulsive behaviors, including delay discounting, behavioral inhibition and a newly proposed measure of inattention. Our findings support the hypothesis that drugs of abuse alter performance across independent behavioral measures of impulsivity. The findings lay the groundwork for studying the cognitive and neurobiological substrates of impulsivity, and for future studies on the role of impulsive behavior as both facilitator and a result of drug use. [source] Public Sector Decentralisation: Measurement Concepts and Recent International Trends,FISCAL STUDIES, Issue 3 2005Dan Stegarescu Abstract This paper deals with the problems encountered in defining and measuring the degree of fiscal decentralisation. Drawing on a recent analytical framework of the OECD, different measures of tax autonomy and revenue decentralisation are presented which consider the tax-raising powers of sub-central governments. Taking account of changes in the assignment of decision-making competencies over the course of time, new time series of annual data on the degree of fiscal decentralisation are provided for 23 OECD countries over the period between 1965 and 2001. It is shown that common measures usually employed tend to overestimate the extent of fiscal decentralisation considerably. Evidence is also provided of increasing fiscal decentralisation in a majority of OECD countries during the last three decades. [source] Analyzing the Relationship Between Smoking and Coronary Heart Disease at the Small Area Level: A Bayesian Approach to Spatial ModelingGEOGRAPHICAL ANALYSIS, Issue 2 2006Jane Law We model the relationship between coronary heart disease and smoking prevalence and deprivation at the small area level using the Poisson log-linear model with and without random effects. Extra-Poisson variability (overdispersion) is handled through the addition of spatially structured and unstructured random effects in a Bayesian framework. In addition, four different measures of smoking prevalence are assessed because the smoking data are obtained from a survey that resulted in quite large differences in the size of the sample across the census tracts. Two of the methods use Bayes adjustments of standardized smoking ratios (local and global adjustments), and one uses a nonparametric spatial averaging technique. A preferred model is identified based on the deviance information criterion. Both smoking and deprivation are found to be statistically significant risk factors, but the effect of the smoking variable is reduced once the confounding effects of deprivation are taken into account. Maps of the spatial variability in relative risk, and the importance of the underlying covariates and random effects terms, are produced. We also identify areas with excess relative risk. [source] Carbon emission and sequestration by agricultural land use: a model study for EuropeGLOBAL CHANGE BIOLOGY, Issue 6 2002L. M. Vleeshouwers Abstract A model was developed to calculate carbon fluxes from agricultural soils. The model includes the effects of crop (species, yield and rotation), climate (temperature, rainfall and evapotranspiration) and soil (carbon content and water retention capacity) on the carbon budget of agricultural land. The changes in quality of crop residues and organic material as a result of changes in CO2 concentration and changed management were not considered in this model. The model was parameterized for several arable crops and grassland. Data from agricultural, meteorological, soil, and land use databases were input to the model, and the model was used to evaluate the effects of different carbon dioxide mitigation measures on soil organic carbon in agricultural areas in Europe. Average carbon fluxes under the business as usual scenario in the 2008,2012 commitment period were estimated at 0.52 tC ha,1 y,1 in grassland and ,0.84 tC ha,1 y,1 in arable land. Conversion of arable land to grassland yielded a flux of 1.44 tC ha,1 y,1. Farm management related activities aiming at carbon sequestration ranged from 0.15 tC ha,1 y,1 for the incorporating of straw to 1.50 tC ha,1 y,1 for the application of farmyard manure. Reduced tillage yields a positive flux of 0.25 tC ha,1 y,1. The indirect effect associated with climate was an order of magnitude lower. A temperature rise of 1 °C resulted in a ,0.05 tC ha,1 y,1 change whereas the rising CO2 concentrations gave a 0.01 tC ha,1 y,1 change. Estimates are rendered on a 0.5 × 0.5° grid for the commitment period 2008,2012. The study reveals considerable regional differences in the effectiveness of carbon dioxide abatement measures, resulting from the interaction between crop, soil and climate. Besides, there are substantial differences between the spatial patterns of carbon fluxes that result from different measures. [source] Suboptimal provision of preventive healthcare due to expected enrollee turnover among private insurersHEALTH ECONOMICS, Issue 4 2010Bradley Herring Abstract Many preventive healthcare procedures are widely recognized as cost-effective but have relatively low utilization rates in the US. Because preventive care is a present-period investment with a future-period expected financial return, enrollee turnover among private insurers lowers the expected return of this investment. In this paper, I present a simple theoretical model to illustrate the suboptimal provision of preventive healthcare that results from insurers ,free riding' off of the provision from others. I also provide an empirical test of this hypothesis using data from the Community Tracking Study's Household Survey. I use lagged market-level measures of employment-induced insurer turnover to identify variation in insurers' expectations and test for the effect of turnover on several different measures of medical utilization. As expected, I find that turnover has a significantly negative effect on the utilization of preventive services and has no effect on the utilization of acute services used as a control. Copyright © 2009 John Wiley & Sons, Ltd. [source] Maternal health: does prenatal care make a difference?HEALTH ECONOMICS, Issue 5 2006Karen Smith Conway Abstract This research attempts to close an important gap in health economics regarding the efficacy of prenatal care and policies designed to improve access to that care, such as Medicaid. We argue that a key beneficiary , the mother , has been left completely out of the analysis. If prenatal care significantly improves the health of the mother, then concluding that prenatal care is ,ineffective' or that the Medicaid expansions are a ,failure' is premature. This paper seeks to rectify the oversight by estimating the impact of prenatal care on maternal health and the associated cost savings. We first set up a joint maternal,infant health production framework that informs our empirical analysis. Using data from the National Maternal and Infant Health Survey, we estimate the effects of prenatal care on several different measures of maternal health such as body weight status and excessive hospitalizations. Our results suggest that receiving timely and adequate prenatal care may increase the probability of maintaining a healthy weight after the birth and, perhaps for blacks, of avoiding a lengthy hospitalization after the delivery. Given the costs to society of obesity and hospitalization, these are benefits worth exploring before making conclusions about the effectiveness of prenatal care , and Medicaid. Copyright © 2006 John Wiley & Sons, Ltd. [source] Employed Family Physician Satisfaction and Commitment to Their Practice, Work Group, and Health Care OrganizationHEALTH SERVICES RESEARCH, Issue 2 2010Ben-Tzion Karsh Objective. Test a model of family physician job satisfaction and commitment. Data Sources/Study Setting. Data were collected from 1,482 family physicians in a Midwest state during 2000,2001. The sampling frame came from the membership listing of the state's family physician association, and the analyzed dataset included family physicians employed by large multispecialty group practices. Study Design and Data Collection. A cross-sectional survey was used to collect data about physician working conditions, job satisfaction, commitment, and demographic variables. Principal Findings. The response rate was 47 percent. Different variables predicted the different measures of satisfaction and commitment. Satisfaction with one's health care organization (HCO) was most strongly predicted by the degree to which physicians perceived that management valued and recognized them and by the extent to which physicians perceived the organization's goals to be compatible with their own. Satisfaction with one's workgroup was most strongly predicted by the social relationship with members of the workgroup; satisfaction with one's practice was most strongly predicted by relationships with patients. Commitment to one's workgroup was predicted by relationships with one's workgroup. Commitment to one's HCO was predicted by relationships with management of the HCO. Conclusions. Social relationships are stronger predictors of employed family physician satisfaction and commitment than staff support, job control, income, or time pressure. [source] Retrograde amnesia and the volume of critical brain structuresHIPPOCAMPUS, Issue 8 2003M.D. Kopelman Abstract There are many controversies concerning the structural basis of retrograde amnesia (RA). One view is that memories are held briefly within a medial temporal store ("hippocampal complex") before being "consolidated" or reorganised within temporal neocortex and/or networks more widely distributed within the cerebral cortex. An alternative view is that the medial temporal lobes are always involved in the storage and retrieval (reactivation) of autobiographical memories (multiple trace theory). The present study used quantitative magnetic resonance imaging (MRI) in 40 patients with focal pathology/volume loss in different sites, to examine the correlates of impairment on three different measures of RA. The findings supported the view that widespread neural networks are involved in the storage and retrieval of autobiographical and other remote memories. Brain volume measures in critical structures could account for 60% of variance on autobiographical memory measures (for incidents and facts) in diencephalic patients and for 60,68% of variance in patients with frontal lesions. Significant correlations with medial temporal lobe volume were found only in the diencephalic group, in whom they were thought to reflect thalamic changes, but not in patients with herpes encephalitis or hypoxia in whom the temporal lobes were particularly implicated. The latter finding fails to support one of the main predictions of multiple trace theory, as presently expounded. © 2003 Wiley-Liss, Inc. [source] Psychological essentialism and cultural variation: children's beliefs about aggression in the United States and South AfricaINFANT AND CHILD DEVELOPMENT, Issue 2 2008Jessica W. Giles Abstract The present study compared indigenous South African versus African-American schoolchildren's beliefs about aggression. Eighty 7,9 year olds (40 from each country) participated in interviews in which they were asked to make inferences about the stability, malleability, and causal origins of aggressive behaviour. Although a minority of participants from both countries endorsed essentialist beliefs about aggression, South African children were more likely than American children to do so. Results also revealed some degree of coherence in children's patterns of beliefs about aggression, such that children responded across superficially different measures in ways that appear theoretically consistent. The authors consider these findings in light of debates concerning the role of cultural forces in shaping person perception. Copyright © 2007 John Wiley & Sons, Ltd. [source] Convergence between physiological, facial and verbal self-report measures of affective empathy in childrenINFANT AND CHILD DEVELOPMENT, Issue 3 2007Xenia Anastassiou-Hadjicharalambous Abstract The present study investigated the degree of convergence between three different measures of vicarious affective responsiveness (affective empathy),verbal self-report, facial expression and change in heart rate,in typically developing children (N=29, aged 8,10 years), when presented with an emotionally evocative film. Although convergence between physiological and verbal measures was only at chance levels, convergence between facial and physiological measures, and between facial and verbal measures was statistically significant, but low (,=0.30 and 0.22, respectively, p<0.01). These findings have important implications for the assessment of empathy in children and indicate that generalization of results across methods should be undertaken with caution. Copyright © 2007 John Wiley & Sons, Ltd. [source] Core Inflation and Monetary PolicyINTERNATIONAL FINANCE, Issue 3 2001Marianne Nessén What are the implications of targeting different measures of inflation? We extend a basic theoretical framework of optimal monetary policy under inflation targeting (Svensson 1997) to include several components of CPI inflation, and analyse the implications of using different measures of inflation as the target variable , headline CPI inflation, core inflation, and CPI excluding interest rates. Our main results are the following. First, barring the interest rate component, temporary shocks to inflation do not affect optimal monetary policy under any regime. Second, indirect (second-round) effects of disturbances on target variables need to be accounted for properly. Simply excluding seemingly temporary disturbances from the reaction function risks leading to inappropriate policy responses. Third, it may be optimal to respond to changes in one measure of inflation even if the target is defined in terms of another. Fourth, the presence of the direct interest rate component in the CPI tends to push optimal monetary policy in an expansionary direction. The net effect, considering also the traditional channel, however, depends on the nature of the initial disturbance. [source] A methodological and operative framework for the evaluation of an e-health projectINTERNATIONAL JOURNAL OF HEALTH PLANNING AND MANAGEMENT, Issue 1 2008Luca Buccoliero Abstract Assessing public sector ICT investments represents the premise for successful implementation of an e-health strategy. The recent literature stresses the importance of going beyond the mere financial and/or technical dimensions of the analysis. Consequently, the paper proposes an example of e-health project evaluation aiming to develop measures which get close to the notion of benefits to the different stakeholders involved: top management, patients, local community. The case study refers to an Italian health care organization that implemented a project of digitalization of its clinical reports production few years ago. Based on on-field research, different approaches are used to assess costs and benefits from different stakeholders' perspectives. The results of a multidimensional evaluation are reported to emphasize the need for different measures to assess the sustainability of an e-health project according to the financial convenience, the social role of the organization, and the contingent situation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Adding an Alcohol-Related Risk Score to an Existing Categorical Risk Classification for Older Adults: Sensitivity to Group DifferencesJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2007Sandra R. Wilson PhD OBJECTIVES: To evaluate a new alcohol-related risk score for research use. DESIGN: Using data from a previously reported trial of a screening and education system for older adults (Computerized Alcohol-Related Problems Survey), secondary analyses were conducted comparing the ability of two different measures of risk to detect postintervention group differences: the original categorical outcome measure and a new, finely grained quantitative risk score based on the same research-based risk factors. SETTING: Three primary care group practices in southern California. PARTICIPANTS: Six hundred sixty-five patients aged 65 and older. MEASUREMENTS: A previously calculated, three-level categorical classification of alcohol-related risk and a newly developed quantitative risk score. RESULTS: Mean postintervention risk scores differed between the three experimental conditions: usual care, patient report, and combined report (P<.001). The difference between the combined report and usual care was significant (P<.001) and directly proportional to baseline risk. The three-level risk classification did not reveal approximately 57.3% of the intervention effect detected by the risk score. The risk score also was sufficiently sensitive to detect the intervention effect within the subset of hypertensive patients (n=112; P=.001). CONCLUSION: As an outcome measure in intervention trials, the finely grained risk score is more sensitive than the trinary risk classification. The additional clinical value of the risk score relative to the categorical measure needs to be determined. [source] Role of larval host plants in the climate-driven range expansion of the butterfly Polygonia c-albumJOURNAL OF ANIMAL ECOLOGY, Issue 3 2007BRIGITTE BRASCHLER Summary 1Some species have expanded their ranges during recent climate warming and the availability of breeding habitat and species' dispersal ability are two important factors determining expansions. The exploitation of a wide range of larval host plants should increase an herbivorous insect species' ability to track climate by increasing habitat availability. Therefore we investigated whether the performance of a species on different host plants changed towards its range boundary, and under warmer temperatures. 2We studied the polyphagous butterfly Polygonia c-album, which is currently expanding its range in Britain and apparently has altered its host plant preference from Humulus lupulus to include other hosts (particularly Ulmus glabra and Urtica dioica). We investigated insect performance (development time, larval growth rate, adult size, survival) and adult flight morphology on these host plants under four rearing temperatures (18,28·5 °C) in populations from core and range margin sites. 3In general, differences between core and margin populations were small compared with effects of rearing temperature and host plant. In terms of insect performance, host plants were generally ranked U. glabra U. dioica > H. lupulus at all temperatures. Adult P. c-album can either enter diapause or develop directly and higher temperatures resulted in more directly developing adults, but lower survival rates (particularly on the original host H. lupulus) and smaller adult size. 4Adult flight morphology of wild-caught individuals from range margin populations appeared to be related to increased dispersal potential relative to core populations. However, there was no difference in laboratory reared individuals, and conflicting results were obtained for different measures of flight morphology in relation to larval host plant and temperature effects, making conclusions about dispersal potential difficult. 5Current range expansion of P. c-album is associated with the exploitation of more widespread host plants on which performance is improved. This study demonstrates how polyphagy may enhance the ability of species to track climate change. Our findings suggest that observed differences in climate-driven range shifts of generalist vs. specialist species may increase in the future and are likely to lead to greatly altered community composition. [source] A Preliminary Investigation into the Utility of the Adult Behavior Checklist in the Assessment of Psychopathology in People with Low IQJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 5 2007Nienke H. Tenneij Background, Achenbach & Rescorla (2003) recently developed the Adult Behavior Checklist (ABCL) to assess psychopathology in the general population. The ABCL should be completed by a proxy informant. The use of proxy informants, instead of self-reporting, makes the ABCL potentially suitable for the assessment of psychopathology in adults with intellectual disability. The aim of the present study was to examine reliability and validity of the ABCL in 124 adults with mild intellectual disability or low IQ, and severe challenging behaviour referred for residential treatment. Methods, The ABCL was completed by two independent informants to assess inter-rater reliability. To examine the validity of the ABCL, its relationship with three measures of functioning was assessed. Furthermore, association between scales of the ABCL and DSM-IV axis I disorders was examined. Results, The ABCL was reliable in terms of internal consistency of its scales, and inter-rater reliability. Relationships between clusters of axis I DSM-IV disorders and scales of the ABCL were found as expected. Moreover, ABCL scales predicted different measures of functioning. Conclusions, The ABCL appears to be a reliable and valid measure to assess psychopathology in persons with mild intellectual disabilities or low IQ, admitted for treatment in facilities for adults with mild intellectual disability and severe challenging behaviour. [source] Repeatability of chick growth and food provisioning in Manx shearwaters Puffinus puffinusJOURNAL OF AVIAN BIOLOGY, Issue 5 2005Catherine M. Gray In animals that produce few offspring during their lifetime, the ability to raise high-quality offspring through the provision of parental care is particularly important for individual fitness. In this paper, we use repeatability analysis of data from two separate time-periods, in the 1970s and the 1990s, to examine parental and environmental effects on chick growth and food provisioning in a long-lived seabird, the Manx shearwater Puffinus puffinus. We test the hypothesis that asymptotic body masses of chicks are most strongly influenced by an individual's genotype, with growth rates intermediate and food provisioning rates most strongly affected by environmental conditions during growth. Peak body masses of chicks raised by the same parents showed significant repeatability in both samples, whereas mass growth rates up to the attainment of peak mass showed significant repeatability only in the 1970s. Several different measures of food provisioning by parents showed no individual consistency in either time-period, in keeping with our predictions. Food provisioning rate was a major determinant of annual variation in chick growth, and so it may seem surprising that Manx shearwaters showed repeatable patterns of chick growth but not of food provisioning, and several possible explanations for this pattern are discussed. [source] The evolutionary species pool hypothesis and patterns of freshwater diatom diversity along a pH gradientJOURNAL OF BIOGEOGRAPHY, Issue 3 2005Jason Pither Abstract Aim, To interpret the unimodal relationship between diatom species richness and lake pH within the context of the evolutionary species pool hypothesis (SPH). We test the following primary prediction arising from the SPH: the size of the potential species pool (PSP) will increase along a gradient representing the historical commonness of different pH environments (pH commonness). To do this we assume that the present-day spatial dominance of near-neutral pH conditions compared with acidic and alkaline conditions reliably mimics the relative spatial availabilities of historical pH conditions among freshwater lakes. We also determine whether local richness represents a constant proportion of PSP size along the pH commonness gradient. Location, Two hundred and thirty-four lakes distributed over a 405,000 km2 region of the north-eastern United States of America. Methods, Sediment diatom morphospecies lists and pH data were acquired from the US Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) website. Using 248 morphospecies that occurred in at least 10 of the 234 lakes, four different measures of PSPs were calculated along the pH gradient. Local species richness was equated with the number of species occurring within the lake. Alpha diversity was equated with the average species richness of lakes with similar pH values. A combination of statistical methods were employed, including correlations, quadratic regression and piecewise regression. Results, PSP size increased significantly with pH commonness for all four measures of PSP size, thus supporting the primary prediction of the evolutionary SPH. Local richness comprised a larger proportion of the PSP within acidic lakes than within circumneutral lakes. Alpha diversity and lake species richness both increased significantly with pH commonness, but the former did so in a two-step fashion. We test and reject several alternative contemporary time-scale explanations for our findings. Main Conclusions, Our findings are consistent with the hypothesis that diatom taxonomic richness is presently lower within acidic and highly alkaline lakes than in circumneutral lakes owing to the limited opportunity in space and/or time for the evolution of suitably adapted species. Whereas ecological processes can explain why certain species are excluded from particular habitats, e.g. acidic lakes, they cannot account for why so few species are adapted to those habitats in the first place. [source] The Market Evaluation of Information in Directors' TradesJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 1-2 2002David Hillier The purpose of this paper is to examine the propensity, characteristics and performance of directors' trades. Consistent with prior research we show that on average, directors outperform the market. However, we also find that there exist a large number of trades which do not share these abnormal share price returns and consequently have little information content. This has important consequences for market participants who use director trading activity as a signal for their own trading strategies. Using different measures of directors' trades based on trade characteristics, we report that purchases by directors are more informative than sales. In addition, the number of directors trading within a twenty day window and the percentage of the directors' holding that is being traded are both important factors in the abnormal share price performance following the trade. [source] Functional and molecular MR imaging of angiogenesis: Seeing the target, seeing it workJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002Michal NeemanArticle first published online: 16 JAN 200 Abstract Intensive research over the last years led to the discovery of multiple molecular pathways and intricate regulatory network controlling the growth and regression of blood vessels in general and angiogenesis in particular. The difficulties in elucidation of the regulation of angiogenesis, stems from the inherent complexity due to participation of many cell types, under a dominant impact of physiological and environmental effects of flow, perfusion, and oxygenation. Major advances were achieved with the use of sophisticated transgenic mice models engineered so as to provide spatially and temporally controlled expression of specific factors alone or in combination. In vivo analysis of these models frequently requires the use of non-invasive imaging modalities for measurement of functional parameters of the vasculature along with dynamic molecular information. Optical methods are extensively applied for the study of angiogenesis [Brown et al., 2001] but provide very limited tissue penetration. MRI offers the advantage of being non-invasive with uniform and relatively high spatial resolution for deep tissues. Multiple MRI approaches for monitoring angiogenesis were developed over the last years, each looking at a particular step in the process. The aim of this paper is to analyze the clinical, pharmaceutical, and biological needs for imaging of angiogenesis, and to critically evaluate the strengths and weaknesses of functional and molecular imaging for monitoring angiogenesis. The inherent problem of validation of different measures of angiogenesis, and the advantages and limitations associated with application of MRI based methods, as surrogates for other measurements of angiogenesis will be discussed. The terms molecular imaging and functional imaging are frequently loosely defined with a significant overlap between the two. For the sake of this paper we will apply a narrower definition of both terms, where molecular imaging will apply to methods directed towards detection of specific biological molecules that participate directly in (regulation of) a physiological process; while functional imaging will be used to describe those methods that aim to detect the physiological response to a defined (molecular) stimulus. J. Cell. Biochem. Suppl. 39: 11,17, 2002. © 2002 Wiley-Liss, Inc. [source] Costs of resistance: genetic correlations and potential trade-offs in an insect immune SystemJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2004S. C. Cotter Abstract Theory predicts that natural selection will erode additive genetic variation in fitness-related traits. However, numerous studies have found considerable heritable variation in traits related to immune function, which should be closely linked to fitness. This could be due to trade-offs maintaining variation in these traits. We used the Egyptian cotton leafworm, Spodoptera littoralis, as a model system to examine the quantitative genetics of insect immune function. We estimated the heritabilities of several different measures of innate immunity and the genetic correlations between these immune traits and a number of life history traits. Our results provide the first evidence for a potential genetic trade-off within the insect immune system, with antibacterial activity (lysozyme-like) exhibiting a significant negative genetic correlation with haemocyte density, which itself is positively genetically correlated with both haemolymph phenoloxidase activity and cuticular melanization. We speculate on a potential trade-off between defence against parasites and predators, mediated by larval colour, and its role in maintaining genetic variation in traits under natural selection. [source] Credit demand in Mozambican manufacturingJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 1 2010Bruce Byiers Abstract This paper uses two industrial firm surveys to identify the key determinants of credit demand in Mozambican manufacturing. We construct five different measures of being credit constrained and estimate desired debt demand. Besides firm size and ownership structure, we find evidence that general manager education and business association membership are associated with whether a firm is credit constrained or not. Using our preferred measure of credit constraint suggests that around 43 per cent of the firms surveyed are constrained, and these enterprises would almost triple their debt burden if borrowing constraints were relaxed. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||