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Kinds of Subsample Selected AbstractsSequencing of DSM-IV criteria of nicotine dependenceADDICTION, Issue 8 2009Denise B. Kandel ABSTRACT Aims To determine whether there is a sequence in which adolescents experience symptoms of nicotine dependence (ND) as per the DSM-IV. Design A two-stage design was implemented to select a multi-ethnic target sample of adolescents from a school survey of 6th,10th graders from the Chicago Public Schools. The cohort was interviewed at home five times with structured computerized interviews at 6-month intervals over a 2-year period. Participants Subsample of new tobacco users (n = 353) who had started to use tobacco within 12 months prior to wave 1 or between waves 1 and 5. Measurements and statistical methods Monthly histories of DSM-IV symptoms of ND were obtained. Log-linear quasi-independence models were estimated to identify the fit of different cumulative models of progression among the four most prevalent dependence criteria (tolerance, impaired control, withdrawal, unsuccessful attempts to quit), indexed by specific symptoms, by gender and race/ethnicity. Findings Pathways varied slightly across groups. The proportions who could be classified in a progression pathway not by chance ranged from 50.7% to 68.8%. Overall, tolerance and impaired control appeared first and preceded withdrawal; impaired control preceded attempts to quit. For males, tolerance was experienced first, with withdrawal a minor path of entry; for females withdrawal was experienced last, tolerance and impaired control were experienced first. For African Americans, tolerance by itself was experienced first; for other groups an alternative path began with impaired control. Conclusions The prevalence and sequence of criteria of ND fit our understanding of the neuropharmacology of ND. The order among symptoms early in the process of dependence may differ from the severity order of symptoms among those who persist in smoking. [source] DESTINATION EFFECTS: RESIDENTIAL MOBILITY AND TRAJECTORIES OF ADOLESCENT VIOLENCE IN A STRATIFIED METROPOLIS,CRIMINOLOGY, Issue 3 2010PATRICK SHARKEY Two landmark policy interventions to improve the lives of youth through neighborhood mobility,the Gautreaux program in Chicago and the Moving to Opportunity (MTO) experiments in five cities,have produced conflicting results and have created a puzzle with broad implications: Do residential moves between neighborhoods increase or decrease violence, or both? To address this question, we analyze data from a subsample of adolescents ages 9,12 years from the Project on Human Development in Chicago Neighborhoods, a longitudinal study of children and their families that began in Chicago,the site of the original Gautreaux program and one of the MTO experiments. We propose a dynamic modeling strategy to separate the effects of residential moving across three waves of the study from dimensions of neighborhood change and metropolitan location. The results reveal countervailing effects of mobility on trajectories of violence; whereas neighborhood moves within Chicago lead to an increased risk of violence, moves outside the city reduce violent offending and exposure to violence. The gap in violence between movers within and outside Chicago is explained not only by the racial and economic composition of the destination neighborhoods but also by the quality of school contexts, adolescents' perceived control over their new environment, and fear. These findings highlight the need to simultaneously consider residential mobility, mechanisms of neighborhood change, and the wider geography of structural opportunity. [source] Spatial analysis of dental trauma in 12-year-old schoolchildren in Curitiba, BrazilDENTAL TRAUMATOLOGY, Issue 4 2008Simone Tetu Moysés A geographic information system (GIS) was used, built by means of ArcView GIS 3.2 software and geographical databases of streets and districts defined within the boundaries of the city of Curitiba, provided by Curitiba's Institute of Research and Public Planning (IPPUC). The database used in the study was compiled based on an epidemiological survey undertaken in 1998 on a sample of 2126 schoolchildren 12 years old, residing in outlying urban suburbs distributed over 29 micro-areas in the city of Curitiba. The cases selected for this study were those with a history of dental trauma, thereby comprising a subsample of 327 schoolchildren. The spatial location of the schoolchildren's homes enabled the events to be visualized on a cartographic basis. The variables of gender, aetiology of the trauma and areas of substandard living conditions were included in the analysis and construction of thematic maps, thus making possible a descriptive analysis of the spatial distribution of dental trauma in the city. Intra-urban differentials were identified in the prevalence of dental trauma in 12-year-old schoolchildren in Curitiba. A greater concentration of occurrences was observed in the eastern region of the city, especially in areas of substandard living conditions. It was possible to conclude that socio-environmental and geophysical factors are associated with the determination of dental trauma in the city of Curitiba, pointing to the need for the development of public policies especially aimed at areas and populations at greater risk. [source] Psychometric evaluation of the mini-social phobia inventory (Mini-SPIN) in a treatment-seeking sample,DEPRESSION AND ANXIETY, Issue 6 2007Justin W. Weeks M.A. Abstract The Mini-Social Phobia Inventory (Mini-SPIN) is a 3-item, self-rated screening instrument to assess social anxiety disorder, but its psychometric properties have not yet been examined in a sample seeking treatment for psychiatric disorders. We analyzed responses from 291 adults who telephoned the Adult Anxiety Clinic of Temple (AACT) seeking treatment for social anxiety or generalized anxiety and worry. The Mini-SPIN demonstrated strong internal consistency. Support for the convergent validity of the Mini-SPIN was provided by moderate correlations with several self-report measures and a clinician-administered measure of social anxiety completed by the subsample of callers who later came to the AACT for evaluation. Furthermore, the Mini-SPIN correlated significantly with two of three measures of functional disability, but not with a measure of life satisfaction. Correlations with measures of other constructs were nonsignificant, providing support for the discriminant validity of the Mini-SPIN. In addition, a cutoff score of 6 on the Mini-SPIN yielded strong sensitivity and diagnostic efficiency in the subsample of treatment seekers that later completed pretreatment evaluation, although the specificity of this cutoff score was not optimal in this sample. Overall, the Mini-SPIN demonstrated sound psychometric properties in this treatment-seeking sample. Depression and Anxiety 24:382,391, 2007. Published 2006 Wiley-Liss, Inc. [source] Posttraumatic stress disorder and the structure of common mental disordersDEPRESSION AND ANXIETY, Issue 4 2002Brian J. Cox Ph.D. Abstract Krueger [1999: Arch Gen Psychiatry 56:921,926] identified a three-factor structure of psychopathology that explained the covariation or grouping of common mental disorders found in the U.S. National Comorbidity Survey (NCS) [Kessler et al., 1994: Arch Gen Psychiatry 51:8,19]. These three fundamental groupings included an externalizing disorders factor and two internalizing disorders factors (anxious-misery and fear). We extended this research through the examination of additional data from a large subsample of the NCS (n=5,877) that contained diagnostic information on posttraumatic stress disorder (PTSD). Factor analytic findings revealed that PTSD showed no affinity with the fear factor defined by panic and phobic disorders, and instead loaded on the anxious-misery factor defined primarily by mood disorders. An identical pattern of results emerged for both lifetime PTSD and 12-month PTSD prevalence figures. Implications of these findings for the classification of PTSD and research on its etiology are briefly discussed. © 2002 Wiley-Liss, Inc. [source] The relationship between childhood trauma history and the psychotic subtype of major depressionACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010B. A. Gaudiano Gaudiano BA, Zimmerman M. The relationship between childhood trauma history and the psychotic subtype of major depression. Objective:, Increasing evidence exists linking childhood trauma and primary psychotic disorders, but there is little research on patients with primary affective disorders with psychotic features. Method:, The sample consisted of adult out-patients diagnosed with major depressive disorder (MDD) at clinic intake using a structured clinical interview. Patients with MDD with (n = 32) vs. without psychotic features (n = 591) were compared as to their rates of different types of childhood trauma. Results:, Psychotic MDD patients were significantly more likely to report histories of physical (OR = 2.81) or sexual abuse (OR = 2.75) compared with non-psychotic MDD patients. These relationships remained after controlling for baseline differences. Within the subsample with comorbid post-traumatic stress disorder, patients with psychotic MDD were significantly more likely to report childhood physical abuse (OR = 3.20). Conclusion:, Results support and extend previous research by demonstrating that the relationship between childhood trauma and psychosis is found across diagnostic groups. [source] Regional and local influence of grazing activity on the diversity of a semi-arid dung beetle communityDIVERSITY AND DISTRIBUTIONS, Issue 1 2006Jorge M. Lobo ABSTRACT This study analyses the effect of resource availability (i.e. sheep dung) on dung beetle communities in an arid region of Central Spain, both at regional and at local scales. A total of 18 sites within 600 km2 were sampled for the regional analysis and 16 sites within the 30 km2 of an Iberian municipality were sampled for the local analysis. Spatial and environmental characteristics of sampling sites were also compiled at both scales, including measures of grazing activity (livestock density at regional scale, and two counts of rabbit and sheep dung at local scale). At a regional scale, any environmental or spatial variable can help to explain the variation in abundance. However, species richness was related to summer precipitation and composition was related to elevation. At local scale, abundance is not significantly related to any of the environmental variables, but species richness was related to the local amount of sheep dung (27% of variance). The amount of dung in a 2-km buffer around the site accounts for 27,32% of variance in abundance and 60,65% of variance in species richness. The presence of the flock with the highest sheep density explains 53% of abundance variability and 73% of species richness variance. A cluster analysis of localities identified two main groups, one characterized by a lower abundance and species richness that can be considered a nested subsample of the species-rich group. The mean and maximum amount of sheep dung in the sites separated by less than 2 km are the only significant explanatory variables able to discriminate both groups. These results suggest that grazing intensity (and the associated increase in the amount of trophic resources) is a key factor in determining local variation in the diversity and composition of dung beetle assemblages. However, dung beetle assemblages are not spatially independent at the analysed resolution, and the amount of dung in the surroundings seems to be more important for locally collected species than the dung effectively found in the site. Although differences in the availability and quantity of trophic resources among nearby sites could be affecting the population dynamics and dispersion of dung beetles within a locality, sites with larger populations, and greater species numbers would not be able to exercise enough influence as to bring about a complete local faunistic homogenization. [source] Changes in alcohol consumption and beverage preference among adolescents after the introduction of the alcopops tax in GermanyADDICTION, Issue 7 2010Stefanie Müller ABSTRACT Aims The aim of this study is to assess the contribution of the alcopops tax to changes in alcohol consumption and beverage preference among adolescents in Germany. We hypothesize that the decrease of alcohol intake by alcopops is substituted by an increase of alcohol intake by other alcoholic beverages. Design Data came from the German 2003 (n = 10 551) and 2007 (n = 10 598) cross-sectional study of the European School Survey Project on Alcohol and other Drugs (ESPAD). Participants A propensity score-matched subsample of 9th and 10th graders (n = 4694) was used for the analyses. Measurement Alcohol consumption within the last 7 days was assessed by a beverage-specific quantity,frequency index. An individual's beverage preference was assigned for the beverage that had the highest share in total alcohol consumption. Multiple regression analyses were used to assess changes in alcohol consumption; changes in beverage preference were tested using multinomial logistic regression. Findings While alcopop consumption declined after the alcopops tax was implemented, consumption of spirits increased. Changes in beverage preference revealed a decrease in alcopop preference and an increase in the preference for beer and spirits. Conclusions Results indicate a partial substitution of alcopops by spirits and a switch in preference to beverages associated with riskier drinking patterns. Effective alcohol policies to prevent alcohol-related problems should focus upon the reduction of total alcohol consumption instead of regulating singular beverages. [source] A randomized trial of the effects of two novel nicotine replacement therapies on tobacco withdrawal symptoms and user satisfactionADDICTION, Issue 7 2010Hayden McRobbie ABSTRACT Aims To determine effects on craving, user satisfaction, and consumption patterns of two new nicotine replacement therapies (NRT) used for eight hours after overnight tobacco abstinence. Design In a within-subject, cross-over trial participants were randomly assigned Zonnic® nicotine mouth spray (1 mg/spray), Zonnic® nicotine lozenge (2.5 mg), Nicorette® gum (4 mg) and placebo lozenge on each of four study days. Setting University research unit. Participants Forty-seven dependent adult smokers. Measurements Participants rated their urges to smoke, irritability, concentration and restlessness before and during the first hour of product use on a 100-point scale. A subsample of 11 participants provided blood samples for nicotine analysis. Findings All active products reduced craving significantly more than placebo (mean reductions of 28.6, 25.8, 24.7 and 8.9 points for mouth spray, gum, lozenge and placebo). Mouth spray relieved craving faster than placebo and gum with significant reductions within five minutes of use (mean differences of ,14.5 (95% CI: ,23.0 to ,6.0) and ,10.6 (95% CI: ,19.1 to ,2.1) with placebo and gum respectively. Mouth spray produced a faster time to maximum plasma nicotine concentration (14.5 minutes, 95% CI: 8.0 to 21.0) compared to the lozenge (30.3 minutes, 95% CI: 21.1 to 39.5) and gum (45.8 minutes, 95% CI: 36.2 to 55.4). Maximum concentrations of blood nicotine were higher with mouth spray (10.0 ng/ml) and lozenge (10.8 ng/ml) compared to gum (7.8 ng/ml). Both lozenge and mouth spray were well tolerated. Conclusions The mouth spray and lozenge are at least as effective as 4 mg nicotine gum in relieving craving suggesting that they are likely to be effective in aiding smoking cessation. The mouth spray may be particularly useful for acute craving relief. [source] Mental disorders as risk factors for substance use, abuse and dependence: results from the 10-year follow-up of the National Comorbidity SurveyADDICTION, Issue 6 2010Joel Swendsen ABSTRACT Aims The comorbidity of mental disorders and substance dependence is well documented, but prospective investigations in community samples are rare. This investigation examines the role of primary mental disorders as risk factors for the later onset of nicotine, alcohol and illicit drug use, abuse and dependence with abuse. Design The National Comorbidity Survey (NCS) was a nationally representative survey of mental and substance disorders in the United States carried out in 1990,92. The NCS-2 re-interviewed a probability subsample of NCS respondents in 2001,03, a decade after the baseline survey. Participants A total of 5001 NCS respondents were re-interviewed in the NCS-2 (87.6% of baseline sample). Results Aggregate analyses demonstrated significant prospective risks posed by baseline mental disorders for the onset of nicotine, alcohol and illicit drug dependence with abuse over the follow-up period. Particularly strong and consistent associations were observed for behavioral disorders and previous substance use conditions, as well as for certain mood and anxiety disorders. Conditional analyses demonstrated that many observed associations were limited to specific categories of use, abuse or dependence, including several mental disorders that were non-significant predictors in the aggregate analyses. Conclusions Many mental disorders are associated with an increased risk of later substance use conditions, but important differences in these associations are observed across the categories of use, abuse and dependence with abuse. These prospective findings have implications for the precision of prevention and treatment strategies targeting substance use disorders. [source] Symptoms of nicotine dependence in a cohort of Swedish youths: a comparison between smokers, smokeless tobacco users and dual tobacco usersADDICTION, Issue 4 2010Ann Post ABSTRACT Aims To determine whether symptoms of nicotine dependence, addiction and withdrawal symptoms differ between exclusive smokers, exclusive snus (moist snuff) users and dual users. Design A cross-sectional survey of a cohort subsample. Setting County of Stockholm, Sweden. Participants Current exclusive smokers (n = 466), exclusive snus users (n = 209) and dual users (n = 144), mean age 17.6 years. Measurements Self-reported life-time experience of nicotine dependence and withdrawal symptoms in periods of discontinued tobacco use. Selected items from the modified Fagerstöm Tolerance Questionnaire (mFTQ), the Hooked on Nicotine Checklist (HONC) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Findings The odds ratio of endorsing each of four mFTQ items as well as the HONC item investigating the risk of feeling addicted to tobacco was two to five-fold higher for exclusive snus users and for dual users compared to exclusive smokers. One DSM-IV item (difficult to refrain from use) was elevated among dual users compared to smokers. Dual users reported the highest prevalence of any withdrawal symptom in contrast to exclusive snus users, who reported a lower risk of withdrawal symptoms compared to exclusive smokers. Conclusions Smokeless tobacco users show symptoms of nicotine dependence at least as frequently as cigarette smokers. Symptoms of nicotine dependence and of withdrawal during quit attempts are particularly frequent in the subgroup of users who combine smokeless tobacco with smoking. [source] The international monetary system in the last and next 20 yearsECONOMIC POLICY, Issue 47 2006Barry Eichengreen SUMMARY The evolution of exchange rate regimes The last two decades have seen far-reaching changes in the structure of the international monetary system. Europe moved from the European Monetary System to the euro. China adopted a dollar peg and then moved to a basket, band and crawl in 2005. Emerging markets passed through a series of crises, leading some to adopt regimes of greater exchange rate flexibility and others to rethink the pace of capital account liberalization. Interpreting these developments is no easy task: some observers conclude that recent trends are confirmation of the ,bipolar view' that intermediate exchange rate arrangements are disappearing, while members of the ,fear of floating school' conclude precisely the opposite. We show that the two views can be reconciled if one distinguishes countries by their stage of economic and financial development. Among the advanced countries, intermediate regimes have essentially disappeared; this supports the bipolar view for the group of countries for which it was first developed. Within this subgroup, the dominant movement has been toward hard pegs, reflecting monetary unification in Europe. While emerging markets have also seen a decline in the prevalence of intermediate arrangements, these regimes still account for more than a third of the relevant subsample. Here the majority of the evacuees have moved to floats rather than fixes, reflecting the absence of EMU-like arrangements in other parts of the world. Among developing countries, the prevalence of intermediate regimes has again declined, but less dramatically. Where these regimes accounted for two-thirds of the developing country subsample in 1990, they account for a bit more than half of that subsample today. As with emerging markets, the majority of those abandoning the middle have moved to floats rather than hard pegs. The gradual nature of these trends does not suggest that intermediate regimes will disappear outside the advanced countries anytime soon. , Barry Eichengreen and Raul Razo-Garcia [source] Anxiety and depression among abstainers and low-level alcohol consumers.ADDICTION, Issue 9 2009The Nord-Trøndelag Health Study ABSTRACT Aims The aim of this study was to examine the levels of anxiety and depression among individuals consuming low levels of alcohol. Design Prospective and cross-sectional population-based study. Setting and participants This study employed data from the Nord-Trøndelag Health Survey (HUNT-2, n = 38 930). Measurements Alcohol consumption was measured by self-report of usual alcohol consumption during a 2-week period. Low-level alcohol consumption was defined as self-reported abstainers and non-abstainers currently consuming no alcohol. Anxiety and depression were measured using the Hospital Anxiety and Depression Rating Scale. Potential explanatory variables included somatic illness and symptoms, health-related behaviour, socio-economic status and social activity. In a subsample (n = 20 337), we also looked at the impact of previous heavy drinking among abstainers ('sick-quitting'). Findings A U-shaped association between alcohol consumption and the risk of anxiety and depression was found. Abstention was related to increased odds for both case-level anxiety [1.34, 95% confidence interval (CI) 1.19,1.52] and depression (1.52, 95% CI 1.30,1.77). This association was accounted for partly by adjustments for socio-economic status, social network, somatic illness, age (depression only), gender (anxiety only) and ,sick-quitting'. We also identified significant differences between participants who label themselves as abstainers compared to those who report no usual alcohol consumption, but who do not label themselves as abstainers. Conclusions The risk of case-level anxiety and depression is elevated in individuals with low alcohol consumption compared to those with moderate consumption. Individuals who label themselves as abstainers are at particularly increased risk. This increased risk cannot fully be explained by somatic illness, social activity or ,sick-quitting'. [source] Early weaning and alcohol disorders in offspring: biological effect, mediating factors or residual confounding?ADDICTION, Issue 8 2009Rosa Alati ABSTRACT Aims This study explores associations between early weaning and alcohol use disorders in youth and mechanisms by which these associations may operate. Design We used data from the Mater University Study of Pregnancy and its outcomes, an Australian birth cohort study based in Brisbane. Setting and participants: This study is based on a subsample of 2370 participants for whom complete data were available at age 21 years. Length and method of breastfeeding were assessed at 6 months. Measurements Alcohol use disorders were assessed at age 21 using the life-time version of the Composite International Diagnostic Interview,computerized version (CIDI-Auto). We adjusted for maternal age, marital status, education, alcohol, tobacco use, anxiety, depression and maternal attitudes towards the baby. Attention Deficit and Hyperactivity Disorders (ADHD) and Intellect Quotient (IQ) were measured with the Child Behaviour Checklist (5 years) and the Ravens SM (14 years), respectively. Findings Those who had been weaned within 2 weeks of being born and breastfed at regular intervals were at increased risk of meeting criteria for alcohol use disorders at age 21 [odds ratio (OR) 1.71, 95% confidence interval (CI):1.07, 2.72]. Conclusion This study confirms a small but robust association between early weaning and increased risk of alcohol use disorders. [source] Socio-demographic risk factors for alcohol and drug dependence: the 10-year follow-up of the national comorbidity surveyADDICTION, Issue 8 2009Joel Swendsen ABSTRACT Aims Continued progress in etiological research and prevention science requires more precise information concerning the specific stages at which socio-demographic variables are implicated most strongly in transition from initial substance use to dependence. The present study examines prospective associations between socio-demographic variables and the subsequent onset of alcohol and drug dependence using data from the National Comorbidity Survey (NCS) and the NCS Follow-up survey (NCS-2). Design The NCS was a nationally representative survey of the prevalence and correlates of DSM-III-R mental and substance disorders in the United States carried out in 1990,2002. The NCS-2 re-interviewed a probability subsample of NCS respondents a decade after the baseline survey. Baseline NCS socio-demographic characteristics and substance use history were examined as predictors of the first onset of DSM-IV alcohol and drug dependence in the NCS-2. Participants A total of 5001 NCS respondents were re-interviewed in the NCS-2 (87.6% of baseline sample). Findings Aggregate analyses demonstrated significant associations between some baseline socio-demographic variables (young age, low education, non-white ethnicity, occupational status) but not others (sex, number of children, residential area) and the subsequent onset of DSM-IV alcohol or drug dependence. However, conditional models showed that these risk factors were limited to specific stages of baseline use. Moreover, many socio-demographic variables that were not significant in the aggregate analyses were significant predictors of dependence when examined by stage of use. Conclusions The findings underscore the potential for socio-demographic risk factors to have highly specific associations with different stages of the substance use trajectory. [source] A taxometric study of alcohol abuse and dependence in a general population sample: evidence of dimensional latent structure and implications for DSM-VADDICTION, Issue 5 2009Tim Slade ABSTRACT Aims To explore, with the aid of taxometric analysis, whether alcohol abuse and alcohol dependence are each conceptualized most effectively as single latent dimensions or distinct latent categories. Design Data were taken from a nationally representative cross-sectional epidemiological survey of psychiatric and substance use disorders. Setting General population of Australia. Participants A subsample of all respondents who had consumed at least 12 drinks in the year prior to the survey and who had consumed at least three drinks on at least one single day (n = 4920 of a possible 10 641). Measurements DSM-IV criteria for alcohol abuse and dependence were assessed with the Composite International Diagnostic Interview, version 2.1. Two independent taxometric procedures, MAXimum EIGenvalue (MAXEIG) and mean above minus below a cut (MAMBAC), together with analysis of simulated dimensional and categorical data sets, were carried out. Findings Consistent evidence was found for a single latent dimension underlying the symptoms of alcohol dependence. Less consistent evidence of dimensionality was found for the symptoms of alcohol abuse. Conclusions These findings support the growing consensus regarding the need for continuous measures of alcohol use disorders to complement the traditional categorical representations in upcoming versions of the major psychiatric classification systems. [source] In vivo exposure to microcystins induces DNA damage in the haemocytes of the zebra mussel, Dreissena polymorpha, as measured with the comet assayENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2007Guillaume Juhel Abstract The Comet assay was used to investigate the potential of the biotoxin microcystin (MC) to induce DNA damage in the freshwater zebra mussel, Dreissena polymorpha. Mussels maintained in the laboratory were fed daily, over a 21-day period, with one of four strains of the cyanobacterium, Microcystis aeruginosa. Three of the strains produced different profiles of MC toxin, while the fourth strain did not produce MCs. The mussels were sampled at 0, 7, 14, and 21 days by withdrawing haemocytes from their adductor muscle. In addition, a positive control was performed by exposing a subsample of the mussels to water containing cadmium chloride (CdCl2). Cell viability, measured with the Fluorescein Diacetate/Ethidium Bromide test, indicated that the MC concentrations, to which the mussels were exposed, were not cytotoxic to the haemocytes. The Comet assay performed on the haemocytes indicated that exposure to CdCl2 produced a dose-responsive increase in DNA damage, demonstrating that mussel haemocytes were sensitive to DNA-damaging agents. DNA damage, measured as percentage tail DNA (%tDNA), was observed in mussels exposed to the three toxic Microcystis strains, but not in mussels exposed to the nontoxic strain. Toxin analysis of the cyanobacterial cultures confirmed that the three MC-producing strains exhibit different toxin profiles, with the two MC variants detected being MC-LF and MC-LR. Furthermore, the DNA damage that was observed appeared to be strain-specific, with high doses of MC-LF being associated with a higher level of genotoxicity than low concentrations of MC-LR. High levels of MC-LF also seemed to induce relatively more persistent DNA damage than small quantities of MC-LR. This study is the first to demonstrate that in vivo exposure to MC-producing strains of cyanobacteria induces DNA damage in the haemocytes of zebra mussels and confirms the sublethal toxicity of these toxins. Environ. Mol. Mutagen., 2007. © 2006 Wiley-Liss, Inc. [source] Relationship between soil copper content and copper content of selected crop plants in central ChileENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2001Ricardo Badilla-Ohlbaum Abstract A survey of copper levels in agricultural soils of central Chile revealed two soil clusters,one with a mean copper level of 162 mg/kg and one with a mean copper level of 751 mg/kg of soil. Samples of soils from both soil clusters were characterized on the basis of physicochemical characteristics, and copper extractability was compared by saturation and CaCl2 extraction as well as an acid-leaching procedure (TCLP). We also measured the copper content of various tissues of tomato (Lycopersicon esculentum) and onion (Allium cepa) crops growing on these soils. Other than copper levels, soils from the two clusters were quite similar, with slightly greater levels of molybdenum and cadmium in the high-copper soils. Within each cluster, extracted copper levels and total soil copper levels were not correlated. However, the three extraction procedures solubilized significantly more copper from the high-Cu soils. Mineralogical characterization of the soil particles and depth profiles of soil metal levels in a subsample of sites suggested that highly insoluble copper ore and mining wastes might account for the high copper levels. Neither total nor extractable copper levels allowed statistical prediction of the levels of copper in plant tissue. The edible tissues of both crops had the same mean copper content, regardless of the copper soil level. However, copper contents of stems and leaves were significantly higher for plants growing on the high-Cu soils. These results show that in these soils, high copper levels are associated with very insoluble copper species and thus low bioavailability of copper to crop plants. [source] Financial stress, smoking cessation and relapse: results from a prospective study of an Australian national sampleADDICTION, Issue 1 2006Mohammad Siahpush ABSTRACT Aims Our aim was to examine the association between financial stress and subsequent smoking cessation among smokers, and relapse among ex-smokers. Design and participants Data came from the first two waves of the Household Income and Labour Dynamics in Australia (HILDA) survey. The size of the subsample of smokers was 2076, and that of ex-smokers was 2717. Data collection was based on face-to-face interviews. Measurement Eight questionnaire items (e.g. difficulty paying electricity, gas or telephone bills and going without meals due to shortage of money) were used to construct a nine-point financial stress index. Findings Smokers with more financial stress were less likely to quit, with the odds of quitting reducing by 13% (95% CI: 4,21%; P = 0.008) per unit of the financial stress index. Ex-smokers with more financial stress were more likely to relapse (P < 0.001). Conclusions Special programmes may have to be implemented to counter the potentially adverse effects of tobacco price increases on smokers who have financial stress and fail to quit smoking. [source] Most smokeless tobacco use is not a causal gateway to cigarettes: using order of product use to evaluate causation in a national US sampleADDICTION, Issue 8 2003Lynn T. Kozlowski ABSTRACT Aims, To evaluate non-causal and causal patterns of smokeless tobacco (SLT) and cigarette use; to assess the prevalence of ,non-gateway' and possible ,gateway' patterns of SLT use. Design and setting, Data from the Cancer Control Supplement to the 1987 National Health Interview Survey, a representative survey of non-institutionalized adults in the United States. From reported age at first use, participants were categorized by type and sequence of tobacco product use. SUDAAN 8.0.1 was used for statistical analyses. Participants, Males aged 18,34 (n = 3454), weighted to provide estimates of the US population. A subsample of males aged 23,34 (n = 2614) was analyzed to minimize the possibility of future product switching. Measurements, Smoking status, smokeless tobacco (snuff, chewing tobacco, both) use status, age at regular use of cigarettes, age at first use of smokeless tobacco. Findings, Of those 23,34-year-olds who had ever used SLT with or without cigarettes, 77.2% (95% CI: 71.3, 83.3) were classifiable as non-gateway users in that 35.0% (95% CI: 29.9, 40.1) had only used SLT and 42.2% (95% CI: 36.8, 47.7) had used cigarettes first. Cigarette use in younger cohorts was less common, despite increased SLT use. Those who used cigarettes before moist snuff were 2.1 times more likely to have quit smoking (95% CI 1.21,6.39) than cigarette-only users. Conclusions, The large majority of SLT users are non-gateway users. Causal gateway effects should be of minor concern for policy. SLT may be more likely to prevent smoking than cause it. [source] The neuroanatomy of grapheme,color synesthesiaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2009Lutz Jäncke Abstract Grapheme,color synesthetes perceive particular colors when seeing a letter, word or number (grapheme). Functional neuroimaging studies have provided some evidence in favor of a neural basis for this type of synesthesia. Most of these studies have reported extra activations in the fusiform gyrus, which is known to be involved in color, letter and word processing. The present study examined different neuroanatomical features (i.e. cortical thickness, cortical volume and cortical surface area) in a sample of 48 subjects (24 grapheme,color synesthetes and 24 control subjects), and revealed increased cortical thickness, volume and surface area in the right and left fusiform gyrus and in adjacent regions, such as the lingual gyrus and the calcarine cortex, in grapheme,color synesthetes. In addition, we set out to analyze structural connectivity based on fractional anisotropy (FA) measurements in a subsample of 28 subjects (14 synesthetes and 14 control subjects). In contrast to the findings of a recent neuroanatomical study using modern diffusion tensor imaging measurement techniques, we did not detect any statistically significant difference in FA between synesthetes and non-synesthetes in the fusiform gyri. Our study thus supports the hypothesis of local anatomical differences in cortical characteristics in the vicinity of the V4 complex. The observed altered brain anatomy in grapheme,color synesthetes might be the anatomical basis for this particular form of synesthesia but it is also possible that the detected effects are a consequence (rather than the primary cause) of the life-long experience of grapheme,color synesthesia. [source] Personality variable differences between disease clustersEUROPEAN JOURNAL OF PERSONALITY, Issue 2 2003G. Matthews Previous studies of personality and health have focused mainly on the influence of psychological factors on single diseases such as cancer and coronary heart disease (CHD), thereby neglecting the problem of comorbidity (i.e. the combination of different diseases). The main focus of the present study was the discrimination between single- and multiple-disease conditions on the basis of personality traits. An extensive battery of personality scales implicated in health was administered to a sample of n=5133 individuals of both genders between the ages of 40 and 65. Subjects also reported their health or illness status. A factor analysis of the personality scales yielded five dimensions clearly interpretable as "Emotional Lability", "Type A Behaviour", "Behavioural Control", "Locus of Control over Diseases", and "Psychoticism". Hierarchical cluster analyses of the subsample of participants who reported suffering from more than one disease led to eight clusters representing individuals with different combinations of diseases. Generally, there were very few significant differences between healthy and single-disease participants with regard to personality. However, mean factor scores calculated for "Emotional Lability" were higher across the multiple-disease groups than in the healthy and single-disease groups. No other personality factor showed this trend. In general the results reported here show the important role negative affectivity (e.g. Emotional Lability, Neuroticism, Depression) plays in differentiating between single and multiple diseases. Copyright © 2003 John Wiley & Sons, Ltd. [source] Sampling and analytical plus subsampling variance components for five soil indicators observed at regional scaleEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2009B. G. Rawlins Summary When comparing soil baseline measurements with resampled values there are four main sources of error. These are: i) location (errors in relocating the sample site), ii) sampling errors (representing the site with a sample of material) iii) subsampling error (selecting material for analysis) and iv) analytical error (error in laboratory measurements). In general we cannot separate the subsampling and analytical sources of error (since we always analyse a different subsample of a specimen), so in this paper we combine these two sources into subsampling plus analytical error. More information is required on the relative magnitudes of location and sampling errors for the design of effective resampling strategies to monitor changes in soil indicators. Recently completed soil surveys of the UK with widely differing soils included a duplicate site and subsampling protocol to quantify ii), and the sum of iii) and iv) above. Sampling variances are estimated from measurements on duplicate samples , two samples collected on a support of side length 20 m separated by a short distance (21 m). Analytical and subsampling variances are estimated from analyses of two subsamples from each duplicate site. After accounting for variation caused by region, parent material class and land use, we undertook a nested analysis of data from 196 duplicate sites across three regions to estimate the relative magnitude of medium-scale (between sites), sampling and subsampling plus analytical variance components, for five topsoil indicators: total metal concentrations of copper (Cu), nickel (Ni) and zinc (Zn), soil pH and soil organic carbon (SOC) content. The variance components for each indicator diminish by about an order of magnitude from medium-scale, to sampling, to analytical plus subsampling. Each of the three fixed effects (parent material, land use and region) were statistically significant for each of the five indicators. The most effective way to minimise the overall uncertainty of our observations at sample sites is to reduce the sampling variance. [source] Relational Factors and Family Treatment Engagement among Low-Income, HIV-Positive African American MothersFAMILY PROCESS, Issue 1 2003Victoria B. Mitrani Ph.D. Clinically derived hypotheses regarding treatment engagement of families of low-income, HIV-positive, African American mothers are tested using univariate and multivariate logistic regression models. Predictors are baseline family relational factors (family support, mother's desire for involvement with family, and family hassles) and mother's history of substance dependence. The study examines a subsample of 49 mothers enrolled in a clinical trial testing the efficacy of Structural Ecosystems Therapy (SET). SET is a family-based intervention intended to relieve and prevent psychosocial distress associated with HIV/AIDS. Participants in the subsample were randomly assigned to SET and attended at least two therapy sessions. Findings reveal that family relational factors predicted family treatment engagement (family support, p < 004; mother's desire for involvement with family, p < 008; family hassles, p < 027). Family support predicted family treatment engagement beyond the prediction provided by the other relational factors and the mother's own treatment engagement (p < 016). History of substance dependence was neither associated with family treatment engagement nor family support. Post hoc analyses revealed that family hassles (p < 003) and mother's desire for involvement with family (p < 018) were differentially related to family treatment engagement in low-versus high-support families. Implications for clinical practice and future research are discussed. [source] Risk Changes around Calls of Convertible BondsFINANCIAL REVIEW, Issue 3 2010Luis García-Feijóo G14; G32 Abstract We examine changes in equity and asset betas around convertible bond calls and report two major findings. First, calling firms exhibit an increase in asset betas following the call. We argue that the finding is consistent with the implications of the sequential financing theory but not of the backdoor equity financing theory. Second, abnormal returns at call announcements are negative only for the subsample of firms that also exhibit an increase in equity beta. We conclude that risk changes help explain the market reaction to convertible bond calls. [source] Lake responses to reduced nutrient loading , an analysis of contemporary long-term data from 35 case studiesFRESHWATER BIOLOGY, Issue 10 2005ERIK JEPPESEN Summary 1. This synthesis examines 35 long-term (5,35 years, mean: 16 years) lake re-oligotrophication studies. It covers lakes ranging from shallow (mean depth <5 m and/or polymictic) to deep (mean depth up to 177 m), oligotrophic to hypertrophic (summer mean total phosphorus concentration from 7.5 to 3500 ,g L,1 before loading reduction), subtropical to temperate (latitude: 28,65°), and lowland to upland (altitude: 0,481 m). Shallow north-temperate lakes were most abundant. 2. Reduction of external total phosphorus (TP) loading resulted in lower in-lake TP concentration, lower chlorophyll a (chl a) concentration and higher Secchi depth in most lakes. Internal loading delayed the recovery, but in most lakes a new equilibrium for TP was reached after 10,15 years, which was only marginally influenced by the hydraulic retention time of the lakes. With decreasing TP concentration, the concentration of soluble reactive phosphorus (SRP) also declined substantially. 3. Decreases (if any) in total nitrogen (TN) loading were lower than for TP in most lakes. As a result, the TN : TP ratio in lake water increased in 80% of the lakes. In lakes where the TN loading was reduced, the annual mean in-lake TN concentration responded rapidly. Concentrations largely followed predictions derived from an empirical model developed earlier for Danish lakes, which includes external TN loading, hydraulic retention time and mean depth as explanatory variables. 4. Phytoplankton clearly responded to reduced nutrient loading, mainly reflecting declining TP concentrations. Declines in phytoplankton biomass were accompanied by shifts in community structure. In deep lakes, chrysophytes and dinophytes assumed greater importance at the expense of cyanobacteria. Diatoms, cryptophytes and chrysophytes became more dominant in shallow lakes, while no significant change was seen for cyanobacteria. 5. The observed declines in phytoplankton biomass and chl a may have been further augmented by enhanced zooplankton grazing, as indicated by increases in the zooplankton : phytoplankton biomass ratio and declines in the chl a : TP ratio at a summer mean TP concentration of <100,150 ,g L,1. This effect was strongest in shallow lakes. This implies potentially higher rates of zooplankton grazing and may be ascribed to the observed large changes in fish community structure and biomass with decreasing TP contribution. In 82% of the lakes for which data on fish are available, fish biomass declined with TP. The percentage of piscivores increased in 80% of those lakes and often a shift occurred towards dominance by fish species characteristic of less eutrophic waters. 6. Data on macrophytes were available only for a small subsample of lakes. In several of those lakes, abundance, coverage, plant volume inhabited or depth distribution of submerged macrophytes increased during oligotrophication, but in others no changes were observed despite greater water clarity. 7. Recovery of lakes after nutrient loading reduction may be confounded by concomitant environmental changes such as global warming. However, effects of global change are likely to run counter to reductions in nutrient loading rather than reinforcing re-oligotrophication. [source] The effect of fixed-count subsampling on macroinvertebrate biomonitoring in small streamsFRESHWATER BIOLOGY, Issue 2 2000Craig P. Doberstein Summary 1When rigorous standards of collecting and analysing data are maintained, biological monitoring adds valuable information to water resource assessments. Decisions, from study design and field methods to laboratory procedures and data analysis, affect assessment quality. Subsampling - a laboratory procedure in which researchers count and identify a random subset of field samples - is widespread yet controversial. What are the consequences of subsampling? 2To explore this question, random subsamples were computer generated for subsample sizes ranging from 100 to 1000 individuals as compared with the results of counting whole samples. The study was done on benthic invertebrate samples collected from five Puget Sound lowland streams near Seattle, WA, USA. For each replicate subsample, values for 10 biological attributes (e.g. total number of taxa) and for the 10-metric benthic index of biological integrity (B-IBI) were computed. 3Variance of each metric and B-IBI for each subsample size was compared with variance associated with fully counted samples generated using the bootstrap algorithm. From the measures of variance, we computed the maximum number of distinguishable classes of stream condition as a function of sample size for each metric and for B-IBI. 4Subsampling significantly decreased the maximum number of distinguishable stream classes for B-IBI, from 8.2 for fully counted samples to 2.8 classes for 100-organism subsamples. For subsamples containing 100,300 individuals, discriminatory power was low enough to mislead water resource decision makers. [source] Measuring Monetary Policy in Germany: A Structural Vector Error Correction ApproachGERMAN ECONOMIC REVIEW, Issue 3 2003Imke Brüggemann Monetary policy; cointegration; structural VAR analysis Abstract. A structural vector error correction (SVEC) model is used to investigate several monetary policy issues. While being data-oriented the SVEC framework allows structural modeling of the short-run and long-run properties of the data. The statistical model is estimated with monthly German data for 1975,98 where a structural break is detected in 1984. After splitting the sample, three stable long-run relations are found in each subsample which can be interpreted in terms of a money-demand equation, a policy rule and a relation for real output, respectively. Since the cointegration restrictions imply a particular shape of the long-run covariance matrix this information can be used to distinguish between permanent and transitory innovations in the estimated system. Additional restrictions are introduced to identify a monetary policy shock. [source] Gender Wage Differences in West Germany: A Cohort AnalysisGERMAN ECONOMIC REVIEW, Issue 4 2002Bernd Fitzenberger A comprehensive descriptive analysis of gender wage differences over a long time period does not exist for West Germany. Using an empirical approach which explicitly takes into account changes of wage distributions for both males and females as well as life,cycle and birth cohort effects, we go beyond conventional decomposition techniques of the average gender wage gap. The paper provides stylized facts of the level and dynamics of the gender wage gap from 1975,95. The empirical analysis is based upon the IAB employment subsample. Our findings confirm the importance of distributional effects relating to skill level and employment status. While life,cycle wage growth is in general much lower for females compared to males, comparing their estimated time trends implies that the gender wage gap has narrowed substantially in the lower part of the wage distribution especially for low, and medium,skilled females but much less so in the upper part of the wage distribution. Surprisingly, we do not find any cohort effects for wages of female employees. [source] Experiences of seeking help from health professionals in a sample of women who experienced domestic violenceHEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 1 2003Loraine Bacchus BSc MA PhD Abstract The present paper describes a qualitative study of women who suffered domestic violence. The aim was to explore their experiences of seeking help from health professionals and assess their psychological health. Purposive sampling was used to select a subsample from a larger sample of women who were screened for domestic violence as part of a study undertaken at Guy's and St Thomas' Hospitals in London, UK. In-depth, semi-structured interviews were conducted with the subsample of women during the postpartum period (up to 14 months). Interviews were conducted in women's homes and general practitioners' (GPs) surgeries. The sample consisted of 10 women who had experienced domestic violence in the past 12 months (including the current pregnancy), and six women who had experienced domestic violence in the past 12 months but not the current pregnancy. The main outcome measures included: women's experiences of seeking help from health professionals; and assessment for postnatal depression, post-traumatic stress disorder (PTSD) and psychological distress. Women scored highly on measures of postnatal depression and PTSD. With regard to seeking help, there was a tendency for women to regard GPs, and accident and emergency staff as less helpful compared with health visitors in responding to domestic violence. Lack of privacy, continuity of care and time constraints were dominant themes which emerged from women's contacts with health professionals. Very few women voluntarily disclosed domestic violence to a health professional and even fewer were asked directly about domestic violence by one. It is important for health professionals to enquire about domestic violence in a sensitive manner and provide a response that takes into accounts the complexity of women's needs. Domestic violence training is necessary to equip health professionals with the knowledge and skills they need to respond to domestic violence more effectively. [source] | ||||||||||||||||||||||||||||||||||||||||