Home About us Contact
|
Home About us Contact | ||
|
|
||
Older Cohort (older + cohort)
Selected AbstractsHomicide and schizophrenia: maybe treatment does have a preventive effectCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 1 2001Martin Erb Background Persons with schizophrenia have been found to be at increased risk for homicide as compared with the general population. The increased risk may be associated with the implementation of the policy of deinstitutionalization. Method Persons with schizophrenia who had committed or attempted homicide in the German state of Hessen from 1992 to 1996 and in the Federal Republic of Germany from 1955 to 1964 were compared. Results Schizophrenia increased the risk of homicide 16.6 times (95% CI 11.2,24.5) in the recent cohort and 12.7 times (95% CI 11.2,14.3) in the older cohort. These odds ratios are not statistically different. The lack of appropriate services for chronic high-risk patients and the non-use of mental health services by first episode, acutely psychotic patients were associated with homicide. Conclusion There has been no increase in the risk of homicide among persons with schizophrenia since the implementation of the policy of deinstitutionalization. The examination of the recent period suggests that the provision of specialized long-term care to persons with schizophrenia who are at high risk for violent behaviour and the use of mental health services by acutely psychotic persons may reduce the risk of homicide. Copyright © 2001 Whurr Publishers Ltd. [source] The association of snus and smoking behaviour: a cohort analysis of Swedish males in the 1990sADDICTION, Issue 9 2009Magnus Stenbeck ABSTRACT Background The European Union has banned sales of moist snuff (snus) in all member states, with the exception of Sweden. The ban is motivated by the potential adverse health effects of snus, but snus may also help people to avoid smoking or stop tobacco use. Aims The purpose of this study is to investigate the association between snus and smoking behaviour. Measurements The Swedish Survey of Living Conditions (ULF) health interview panel running from 1988/9 to 1996/7 was used to examine the gross and net flows between smoking and snus among Swedish males. Females were excluded from the analysis due to low snus prevalence. Contingency table models were used to investigate several hypotheses about the relationships between snus and smoking behaviour. Findings We found clear associations between the two habits. For the younger cohort (age 16,44 years), snus use contributed to approximately six smoking quitters per smoking starter attributable to snus. For the older cohort (age 45,84) there were slightly more than two quitters per starter. In terms of odds ratios, in the younger group smoking cessation attributable to snus was twice as common as smoking initiation, but in the older group the odds of starting smoking attributable to snus was 2.5 times higher than for quitting. Conclusions Snus contributed to the reduction of smoking among Swedish males in the 1990s. Snus had different effects among non-smokers and smokers in different age groups. [source] Estimating causal effects from observational data with a model for multiple biasINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2007Michael Höfler Abstract Conventional analyses of observational data may be biased due to confounding, sampling and measurement, and may yield interval estimates that are much too narrow because they do not take into account uncertainty about unknown bias parameters, such as misclassification probabilities. We used a simple, multiple bias adjustment method to estimate the causal effect of social anxiety disorder (SAD) on subsequent depression. A Monte Carlo sensitivity analysis was applied to data from the Early Developmental Stages of Psychiatry (EDSP) study, and bias due to confounding, sampling and measurement was modelled. With conventional logistic regression analysis, the risk for depression was elevated in the presence of SAD only in the older cohort (age 17,24 years at baseline assessment); odds ratio (OR) = 3.06, 95% confidence interval (CI) 1.64,5.70, adjusted for sex and age. The bias-adjusted estimate was 2.01 with interval limits of 0.61 and 9.71. Thus, given the data and the bias model used, there was considerably more uncertainty about the real effect, but the probability that SAD increases the risk for subsequent depression (OR > 1) was 88.6% anyway. Multiple bias modelling, if properly used, reveals the necessity for a better understanding of bias, suggesting a need to conduct larger and more adequate validation studies on instruments that are used to diagnose mental disorders. Copyright © 2007 John Wiley & Sons, Ltd. [source] Effect of Statin (HMG-Co-A-Reductase Inhibitor) Use on 1-Year Mortality and Hospitalization Rates in Older Patients with Cardiovascular Disease Living in Nursing HomesJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2002Charles B. Eaton MD OBJECTIVES: To quantify the effect of statins on 1-year mortality, hospitalizations, and decline in physical function among patients with cardiovascular disease (CVD) aged 65 and older living in nursing homes. DESIGN: Retrospective cohort study. SETTING: All Medicare/Medicaid certified nursing homes (N = 1,492) in Maine, New York, Mississippi, and South Dakota. PARTICIPANTS: We identified 51,559 older patients with CVD from a population database that merged sociodemographic data and functional, clinical, and drug treatments from more than 300,000 newly admitted nursing home residents from 1992 to 1997. Statin users (n = 1,313) were matched with nonusers (n = 1,313) in the same facilities. MEASUREMENTS: All-cause mortality, hospitalization, combined endpoint of mortality or hospitalization, and decline in physical function were determined at 1 year, and survival analysis was performed. RESULTS: Prevalence of statin use in this frail older cohort with CVD was 2.6%. Statin use varied by age, gender, comorbid condition, medication use, and cognitive and physical function. One-year mortality was 229/1,000 person-years in the statin group and 404/1,000 person-years in the nonusers, with an adjusted hazard rate ratio (HRR) of 0.69, 95% confidence interval (CI) = 0.58,0.81. The estimated number needed to treat was seven (95% CI = 5,13). This association with improved all-cause mortality was evident for women and men and for age groups 75 to 84, and 85 and older. CONCLUSION: Statin therapy is associated with improved clinical outcomes, including reduction in 1-year all-cause mortality, and the combined endpoint of death or hospitalization in a frail older population with CVD. Some caution should be taken in interpreting these results because potential bias from residual confounding could affect these results. [source] Alcohol Dependence and Reproductive Onset: Findings in Two Australian Twin CohortsALCOHOLISM, Issue 11 2008Mary Waldron Background:, Although early alcohol use is a strong predictor of future alcohol problems and adolescent drinking is associated with risky sexual behavior predictive of early childbearing, reproductive dysfunctions associated with delayed childbearing have been reported in adult drinkers. We examine the relationship between lifetime history of alcohol dependence (AD) and timing of first childbirth across reproductive development. Methods:, Data were drawn from two cohorts of Australian twins born between 1893 and 1964 (3634 female and 1880 male twins) and between 1964 and 1971 (3381 female and 2748 male twins). Survival analyses were conducted using Cox proportional hazards regression models predicting age at first childbirth from AD, with sociodemographic characteristics, regular smoking, history of psychopathology, and family and childhood risks included as control variables in adjusted models. Results:, Results suggest alcoholic women in both cohorts show overall delayed reproduction, with little effect of AD on timing of first reproduction in men. Effects of AD are particularly strong for women in the older cohort, where AD is associated with 73% decreased likelihood of first childbirth after age 29 [hazard ratio (HR) = 0.27, 95% CI: 0.10,0.75]. In adjusted models, effects reduce only slightly (HR = 0.29, 95% CI: 0.11,0.80). For women in the young cohort, AD is associated with delayed reproduction after age 24, with 40% decreased likelihood of first childbirth (HR = 0.60, 95% CI: 0.48,0.75). AD remains predictive in adjusted models, but without age interaction (HR = 0.72, 95% CI: 0.62,0.85). Conclusions:, Findings of delayed reproductive onset in alcoholic women are consistent with alcohol-related reproductive dysfunctions, although underlying mechanisms remain largely unknown. To better understand AD differences in reproductive onset, continued research on both biological and psychosocial risks is needed. [source] Spousal Concordance for Alcohol Dependence: Evidence for Assortative Mating or Spousal Interaction Effects?ALCOHOLISM, Issue 5 2007Julia D. Grant Background: Alcohol dependence (AD) is among the most common psychiatric disorders, and impacts the health and well-being of problem drinkers, their family members, and society as a whole. Although previous research has consistently indicated that genetic factors contribute to variance in risk for AD, little attention has been paid to nonrandom mating for AD. When assortative mating occurs for a heritable trait, spouses are genetically correlated and offspring are at increased risk of receiving high-risk genes from both parents. The primary goal of the present analyses is to test hypotheses about the source(s) and magnitude of spousal associations for AD using a twin-spouse design. Methods: DSM-IV AD (without the clustering criterion) was assessed via telephone interview for 5,974 twin members of an older cohort of the Australian Twin Register (born 1902,1964) and 3,814 spouses of the twins. Quantitative genetic modeling was used to determine the extent to which variability in risk for AD was influenced by genetic factors, the extent of spousal association for AD, and whether the association was attributable to assortative mating, reciprocal spousal interaction, or both processes. Results: Genetic factors explained 49% of the variance in risk for AD. There was no evidence of gender differences in the spousal interaction effect, the degree of rater bias, or the association between the twin's report of spouse AD and the spouse's AD phenotype. Either the assortative mating parameter or the spousal interaction parameter could be removed from the model without a significant decrement in fit, but both could not be dropped simultaneously, suggesting a lack of power to differentiate between these 2 causes of spousal correlation. When both effects were included in the model, the spousal correlation was 0.29, the assortative mating coefficient was 0.45 (i.e., "like marries like"), and the reciprocal spousal interaction coefficient was ,0.10 (i.e., after controlling for assortative mating, the additional impact of spousal interactions is slightly protective). Conclusions: These analyses provide evidence of significant spousal associations for AD, with assortative mating increasing spouse similarity and spousal interaction effects decreasing it after controlling for assortative mating. Although the genetic impact is modest, assortative mating results in an increased proportion of offspring exposed to 2 alcoholic parents and the associated detrimental environmental sequelae, and increases the likelihood of offspring inheriting high-risk genes from both parents. [source] Drinks of the Father: Father's Maximum Number of Drinks Consumed Predicts Externalizing Disorders, Substance Use, and Substance Use Disorders in Preadolescent and Adolescent OffspringALCOHOLISM, Issue 12 2002Stephen M. Malone Background The maximum number of drinks consumed in 24 hr seems to be an interesting phenotype related to alcoholism. The goal of the present study was to determine in an epidemiologic sample whether this measure of drinking history in fathers predicted externalizing behavioral disorders, substance use, and substance abuse in preadolescent and adolescent offspring and whether any such associations would be independent of paternal alcohol dependence diagnoses. Methods Subjects were male and female twins from both age cohorts of the Minnesota Twin Family Study, a population-based longitudinal study, and were approximately 11 or 17 years of age, respectively, upon study enrollment. In both age cohorts, diagnoses of conduct disorder, oppositional defiant disorder, and attention-deficit/hyperactivity disorder served as outcome measures. In addition, measures of lifetime substance use and of the presence of symptoms of substance abuse were derived for the 11-year-old cohort when subjects were approximately 14 years old and diagnoses of substance abuse were derived for the older cohort at age 17. An extension of logistic regression using generalized estimating equations served to assess whether paternal maximum alcohol consumption predicted filial outcome measures. Results Paternal maximum alcohol consumption was consistently associated with conduct disorder, substance use, and substance abuse or dependence in male and female offspring. These associations were not mediated by a primary effect of paternal alcoholism. Conclusions Paternal maximum alcohol consumption was uniquely associated with those offspring characteristics most reliably found in adolescent children of alcoholic parents. This phenotype might supplement DSM diagnoses of alcohol dependence to reduce the number of false positives in genetic research. [source] Relation between C-reactive protein levels and body composition in a multiethnic sample of school children in HawaiiAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Daniel E. Brown Objectives: Adipose cells secrete proinflammatory cytokines that stimulate hepatic production of C-reactive protein (CRP). CRP levels are associated with adiposity levels in adults, adolescents, and older children but not in young children (age 2,3). This study examined the relation between CRP, adiposity, and cardiovascular and metabolic variables including blood pressure, glucose, and blood lipids in two young cohorts of children, averaging ,5.5 and 8.5 years, respectively. Methods: Children (N = 125) from eight elementary schools in the multiethnic community of Hilo Hawaii were recruited to fill out questionnaires, undergo anthropometrics and air displacement plethysmography, have resting blood pressure measured, and provide a finger stick blood sample for analysis of CRP, glucose, and blood lipids. Results: There were no significant differences between the cohorts in ethnic make up, household income, or parents' educational attainment. No significant relation was found between CRP and either adiposity or cardiovascular/metabolic variables in the younger cohort. However, significant correlations were found between CRP and adiposity measures and blood pressure in the older cohort. There was no marked difference in association of CRP with BMI versus waist circumference or waist-to-hip ratio. In neither cohort was CRP significantly related to glucose or blood lipids. Conclusions: Both amount of fat mass and time duration for possessing the adipose tissue may be important factors in determining the relation between CRP and both adiposity and blood pressure. Am. J. Hum. Biol. 22:675,679, 2010. © 2010 Wiley-Liss, Inc. [source] The prenatal origins of lung cancer.AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2010People differ in their susceptibility to developing cancer on exposure to carcinogens such as tobacco. What causes this is largely unknown. One possibility is that it is determined by nutritional influences during development that permanently change the structure and function of the baby's body. We studied an older and a younger cohort, totaling 20,431 men and women, born in Helsinki during 1924,1933 and 1934,1944. Their body size at birth had been recorded. Of them, 385 had developed lung cancer. Smoking history was known for 6,822 people. At birth, babies who later developed lung cancer had a high ponderal index (birthweight/length3). This association was confined to people whose mother's height was below the median. Among these people in the older cohort, the hazard ratio associated with a ponderal index >30 kg/m3 was 3.1 (95% CI 1.6,5.9), in comparison to those with a ponderal index of 26 kg/m3 or less (P for trend < 0.001). The equivalent figures for the younger cohort were 2.9 (1.2,7.0, P for trend = 0.001) and this association was independent of smoking. We suggest that a high ponderal index in babies born to short mothers is the result of low amino acid delivery to the fetus in relation to glucose delivery. We hypothesize that this impairs the development of the babies' antioxidant systems and makes them vulnerable to oxidative stress in later life. This is the first evidence that fetal programming may determine vulnerability to carcinogens in humans. humans. Am. J. Hum. Biol. 2010. © 2010 Wiley-Liss, Inc. [source] Second Malignant Neoplasms in Patients Under 40 Years of Age With Laryngeal Cancer,THE LARYNGOSCOPE, Issue 4 2001James T. Albright MD Abstract Objectives/Hypothesis To determine the incidence of second malignant neoplasms (SMN) in patients under 40 years of age with invasive squamous cell carcinoma (SCC) of the larynx. Study Design Retrospective. Methods Using a National Cancer Institute tumor registry database encompassing 1973,1996, the incidence of SMN in patients under 40 years of age with laryngeal cancer was determined and compared with that of the registry's older, more traditional laryngeal cancer population. Median follow-up was 136 months. Results Among the 364 patients under the age of 40 years with laryngeal cancer, 30 (8.2%) had developed a secondary malignancy to date. In comparison, 4876 (21.4%) of 22,786 patients 40 years or older with laryngeal cancer were affected by an SMN. Kaplan-Meier analysis of the younger cohort projected 3.0%, 6.8%, and 10.7% relative risk of developing a SMN at any site over 5-, 10-, and 15-year periods, respectively, after index tumor diagnosis. Similar results for the older cohort were 14.2%, 28.1%, and 39.4% at 5, 10, and 15 years, respectively. Further Kaplan-Meier analysis demonstrated at least a fourfold increased risk for the development of secondary upper aerodigestive tract malignancies among older compared with younger patients. Conclusion Patients under 40 years of age with invasive SCC of the larynx are significantly less likely to develop a second malignancy than their older counterparts. [source] Three centuries of fire in montane pine-oak stands on a temperate forest landscapeAPPLIED VEGETATION SCIENCE, Issue 1 2010Serena R. Aldrich Abstract Question: What was the role of fire in montane pine-oak (Pinus-Quercus) stands under changing human land uses on a temperate forest landscape in eastern North America? Location: Mill Mountain in the central Appalachian Mountains, Virginia, US. Methods: A dendroecological reconstruction of fire history was generated for four stands dominated by xerophytic pine and oak species. The fire chronology began under presettlement conditions following aboriginal depopulation. Subsequent land uses included European settlement, iron mining, logging, and US Forest Service acquisition and fire protection. Results: Fires occurred approximately every 5 years until 1930 without any evidence of a temporal trend in fire frequency. Burning ceased after 1930. Area-wide fires affecting multiple pine stands were common, occurring at intervals of approximately 16 years. Most living pines became established during the late 1800s and early 1900s. Dead pines indicated that an older cohort established ca. 1730. Most hardwoods were established between the 1920s and 1940s. Conclusions: Except for fire protection, changes in land use had no discernible influence on fire frequency. Lightning ignitions and/or large fire extent may have been important for maintaining frequent burning in the 1700s, while fuel recovery may have constrained fire frequency during later periods. The disturbance regime appears to be characterized by frequent surface fires and occasional severe fires, insect outbreaks or other disturbances followed by pine recruitment episodes. Industrial disturbances appear to have had little influence on the pine stands. The greatest impact of industrial society is fire exclusion, which permitted hardwood establishment. [source] Older Australian women's use of dentists: A longitudinal analysis over 6 yearsAUSTRALASIAN JOURNAL ON AGEING, Issue 1 2010David W Sibbritt Aim:, To identify factors associated with dentist consultation by older Australian women. Methods:, Participants from the older cohort of the Australian Longitudinal Study on Women's Health which originally involved 12 432 older women. Results:, The percentage of women who consulted a dentist in the years 1999, 2002 and 2005 were 35%, 36% and 37%, respectively. Women were more likely to consult with a dentist if they lived in urban areas (RR = 1.26; 95% CI: 1.21, 1.32), were non-smokers (RR = 1.38; 95% CI: 1.21, 157), did not have diabetes (RR = 1.16; 95% CI: 1.08, 1.25), had better physical health (RR = 1.02 (95% CI: 1.01, 1.02). Women were less likely to consult with a dentist if they found it difficult to live on their income (RR = 0.90; 95% CI: 085, 0.95). Conclusion:, Access to dentists, cost of consultations and poor health appear to be significant factors influencing visits to a dentist by older Australian women. [source] Attrition in longitudinal studies: who do you lose?AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2006Anne F. Young Objective: To describe the risk factors for various types of attrition in three age cohorts of women in a longitudinal study and to discuss strategies to minimise attrition. Methods: Analysis of survey data from the Australian Longitudinal Study on Women's Health, collected by mailed questionnaire. In 1996, the study recruited and surveyed a national random sample of ,younger' (18,23 years, n=14,247), ,mid-age' (45,50 years, n=13,716), and ,older' women (70,75 years, n=12,432), and began a staggered cycle of mailed follow-up questionnaires: 1998 (mid-age), 1999 (older), 2000 (younger) and so on. Demographic, health and social risk factors for attrition were examined using multivariate analysis. Results: Attrition at survey 2 was highest among younger women (32%), mainly because of participants not being contactable (21%), and lower among the older (16%) and mid-age women (10%). At survey 1, the survey 2 non-respondents were more likely to report having less education, being born in a non-English-speaking country and being a current smoker, in all cohorts, and had poorer health (mid-age and older cohort) and more diffculty managing on their income (younger and mid-age). Conclusion: Although the magnitude of different types of attrition was found to differ by age, there were several risk factors for attrition that remained consistent. These fndings are important to inform future studies on ways to lessen or prevent systematic loss of participants. Implications: Recruitment and follow-up methods in longitudinal studies should be tailored to maximise retention of participants at higher risk of dropout. [source] Glucocorticoid receptor gene variant is associated with increased body fatness in youngstersCLINICAL ENDOCRINOLOGY, Issue 4 2009Paul G. Voorhoeve Summary Objective, Sensitivity to glucocorticoids is known to be highly variable between individuals and is partly determined by polymorphisms in the glucocorticoid receptor (GR) gene. We investigated the relationship between four GR gene polymorphisms and body composition during puberty and at young adult age. Design, An observational study with repeated measurements. Patients, Two comparable young Dutch cohorts with a generational difference of about 20 years were investigated. The first cohort consisted of 284 subjects born between 1961 and 1965. Measurements were performed from 13 to 36 years of age. The second cohort consisted of 235 subjects born between 1981 and 1989. Measurements were performed from 8 to 14 years of age. Measurements, Associations between height, weight, BMI, fat mass (FM) and fat-free mass and four well-known functional polymorphisms were investigated. Results, In boys in the younger cohort, the G-allele of the BclI polymorphism (haplotype 2) was associated with a higher body weight, weight-SDS, BMI, BMI-SDS and FM. These associations were not observed in the older cohort. Irrespective of genotype, the younger cohort showed a significantly higher total FM, body weight and BMI compared with the older cohort. Conclusions, Because the associations between the G-allele of the BclI polymorphism in the GR gene and body FM in boys were only found in a healthy young population, but not in a comparable, generally leaner cohort from an older generation, it is suggested that carriers of this polymorphism are likely to be more vulnerable to fat accumulation in today's obesity promoting environment, than noncarriers. [source] Baby boomer pharmacists: ageing and projections of retirementINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 3 2007Dr DJ Schofield associate professor, director of research Objective To identify ageing and retirement patterns of the pharmacy workforce since 1986 and the implications of those changes for future workforce planning. Method Australian Bureau of Statistics census data from 1986 to 2001 were used to examine ageing of the pharmacy workforce and attrition of pharmacists aged 50 years and over. The number of pharmacists to retire was projected over the next 20 years. Key findings The Australian pharmacy workforce has aged significantly since 1986 (P < 0.01). Forty-one per cent of pharmacists practising in 2001 are predicted to retire by 2026. Baby boomer pharmacists were more likely to work long hours (49+ per week) in 2001 than in 1986, and than generation X pharmacists in 2001. The proportion of women in pharmacy has increased from 39% in 1986 to over 50% in 2001. Women are still more likely to work part-time than males, although they are less likely to do so than they were in 1986. Conversely, the proportion of male pharmacists working part-time is rising. Conclusions With baby boomer and older cohorts currently making up 65% of the pharmacy workforce, their retirement will place increased pressure on a profession already facing severe shortages. The growing proportion of female pharmacists and their generally lower workforce participation mean the potential for continued pharmacy shortages. [source] Maximum Daily 6 Minutes of Activity: An Index of Functional Capacity Derived from Actigraphy and Its Application to Older Adults with Heart FailureJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2010Jason Howell BA OBJECTIVES: To compare the correlation between the maximum 6 minutes of daily activity (M6min) and standard measures of functional capacity in older adults with heart failure (HF) with that in younger subjects and its prognostic utility. DESIGN: Prospective, cohort study. SETTING: Tertiary care, academic HF center. PARTICIPANTS: Sixty, ambulatory, adults, New York Heart Association (NYHA) Class I to III, stratified into young (50.9 ± 9.4) and older cohorts (76.8 ± 8.0). MEASUREMENTS: Correlation between M6min and measures of functional capacity (6-minute walk test; 6MWT) and peak oxygen consumption (VO2) according to cardiopulmonary exercise testing in a subset of subjects. Survival analysis was employed to evaluate the association between M6min and adverse events. RESULTS: Adherence to actigraphy was high (90%) and did not differ according to age. The correlation between M6min and 6MWT was higher in subjects aged 65 and older than in those younger than 65 (correlation coefficient (r=0.702, P<.001 vs r=0.490, P=.002). M6min was also significantly associated with peak VO2 (r=0.612, P=.006). During the study, 26 events occurred (2 deaths, 10 hospitalizations, 8 emergency department visits, and 6 intercurrent illnesses). The M6min was significantly associated with subsequent events (hazard ratio=2.728, 95% confidence interval=1.10,6.77, P=.03), independent of age, sex, ejection fraction, NYHA class, brain natriuretic peptide, and 6MWT. CONCLUSION: The high adherence to actigraphy and association with standard measures of functional capacity and independent association with subsequent morbid events suggest that it may be useful for monitoring older adults with HF. [source] Bullying in school and adolescent sense of empowerment: an analysis of relationships with parents, friends, and teachers,JOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 3 2008Maury Nation Abstract We explore the development of bullying and victimization in school by investigating 11-, 13- and 15-year-olds' sense of interpersonal empowerment with parents, friends and teachers. A national sample of 4386 male and female students from 243 middle and secondary schools in Italy were surveyed. Boys were more likely than girls to be bullies and more likely to have been a bully/victim. Victimization and the likelihood of being both a bully and a victim declined with age. Bullying increased with age among boys whereas for girls it was slightly more prevalent at age 13 than ages 11 or 15. The sense of empowerment students experience with their teachers decreased in the older cohorts. Disempowered relationships with teachers consistently predicted bullying behaviour. Higher social competence was reported by 13- and 15-year-old bullies. Chronically bullied students had lower social competence in all age cohorts. Otherwise, predictors of victimization varied by age: 11-year-old victims felt less empowered by their teachers; 15-year-old victims reported more difficulties in negotiating cooperative relationships with parents. Bullies in all cohorts and younger bully/victims feel less empowered by their teachers. These findings suggest that students who are disempowered by teachers may either compensate by oppressing (bullying) peers or generalize the power differential with peers (become a victim). Copyright © 2007 John Wiley & Sons, Ltd. [source] Religion, social mobility and education in ScotlandTHE BRITISH JOURNAL OF SOCIOLOGY, Issue 3 2006Lindsay Paterson Abstract The relationship among religion, education and social mobility in Scotland is analysed statistically using the Scottish Household Survey of 2001. The large sample size allows much greater statistical power for this purpose than any previous source, and thus allows a more reliable assessment of claims that the stratifying effect of religion in Scotland may have declined. The questions investigated are as follows. What are the religious differences in the distributions of class origins and class destinations, in the movement between these (absolute mobility), and in the association of these (relative mobility, or social fluidity)? Do changes in social fluidity across cohorts vary among people with different religious affiliation? Are there religious differences in the association of origins and education, in the association of education and destinations, or in the role of education in social fluidity, and do any of these vary over cohorts? The conclusions are that, in younger cohorts, there is no religious difference in social status, and that in older cohorts Catholics are generally of lower status than Protestants and the non-religious. Social fluidity does not, however, vary among religious groups, even for older cohorts, and does not change over time. The reason for convergence in social status of religious groups over time is probably the equalizing of educational attainment among the groups: there is no evidence for any of the cohorts that the labour-market rewards to education differ by religion. [source] Landscape structure influences tree density patterns in fragmented woodlands in semi-arid eastern AustraliaAUSTRAL ECOLOGY, Issue 6 2009VALERIE J. DEBUSE Abstract Landscape and local-scale influences are important drivers of plant community structure. However, their relative contribution and the degree to which they interact remain unclear. We quantified the extent to which landscape structure, within-patch habitat and their confounding effects determine post-clearing tree densities and composition in agricultural landscapes in eastern subtropical Australia. Landscape structure (incorporating habitat fragmentation and loss) and within-patch (site) features were quantified for 60 remnant patches of Eucalyptus populnea (Myrtaceae) woodland. Tree density and species for three ecological maturity classes (regeneration, early maturity, late maturity) and local site features were assessed in one 100 × 10 m plot per patch. All but one landscape characteristic was determined within a 1.3-km radius of plots; Euclidean nearest neighbour distance was measured inside a 5-km radius. Variation in tree density and composition for each maturity class was partitioned into independent landscape, independent site and joint effects of landscape and site features using redundancy analysis. Independent site effects explained more variation in regeneration density and composition than pure landscape effects; significant predictors were the proportion of early and late maturity trees at a site, rainfall and the associated interaction. Conversely, landscape structure explained greater variation in early and late maturity tree density and composition than site predictors. Area of remnant native vegetation within a landscape and patch characteristics (area, shape, edge contrast) were significant predictors of early maturity tree density. However, 31% of the explained variation in early mature tree differences represented confounding influences of landscape and local variables. We suggest that within-patch characteristics are important in influencing semi-arid woodland tree regeneration. However, independent and confounding effects of landscape structure resulting from previous vegetation clearing may have exerted a greater historical influence on older cohorts and should be accounted for when examining woodland dynamics across a broader range of environments. [source] Optimal management of the New Zealand longfin eel (Anguilla dieffenbachii),AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 4 2005Graeme J. Doole Annual recruitment of the New Zealand longfin eel (Anguilla dieffenbachii) has decreased by 75 per cent since significant levels of commercial fishing began in the early 1970s. This motivates application of a multiple-cohort bioeconomic model to a New Zealand longfin eel fishery to investigate its optimal management and ascertain the suitability of existing regulatory policy. The use of historical harvest to calculate total allowable catch is asserted to be unsustainable based on recovery dynamics. In addition, individual transferable quota systems are argued to be fundamentally flawed for the protection of longfin fisheries because of high-grading, low-surplus production and a current lack of effective stock-assessment procedures. Area closure and the spatial definition of harvest rights are attractive alternatives given the territoriality of longfins and high larval spillover. The importance of unfished reserves is reinforced when significant uncertainties regarding population strength, harvest intensity and growth dynamics are considered. Restriction of exploitation to older cohorts in fished areas is demonstrated to maximise economic yield. [source] Cohort patterns in Canadian earnings: assessing the role of skill premia in inequality trendsCANADIAN JOURNAL OF ECONOMICS, Issue 4 2000Paul Beaudry In this paper we document the pattern of change in age-earnings profiles across cohorts and evaluate its implications. Using synthetic cohorts from the survey of Consumer Finances over the period 1971 to 1993, wwe show that the age-earnings profiles of Canadian men have been deteriorating for more recentcohorts in comparison with older cohorts. We find this pattern for both high school and university educated workers. In no case do we find evidence that the return to gaining experience has been increasing over time, nor do we find increased within-cohort dispersion of earnings. We view these findings as conflicting with the hypothesis that increased skill premia largely explain the observed increase in dispersion of male weekly earnings. JEL Classification: J31, O33 Ce mémoire documente le pattern de changements dans les relations âges-gains d'une cohorte à l'autre, et en analyse les implications. Utilisant des cohortes synthétiques pour la période 1971,93, on montre que les profils âges-gains des hommes au Canada se sont détériorés dans les cohortes les plus récentes. On ne trouve pas de résultats qui montreraient que le rendement sur l'expérience accumulée s'est accru dans le temps ou qu'il y a dispersion accrue des gains à l'intérieur des cohortes. Les auteurs suggèrent que ces résultats contredisent l'hypothèse que des primes accrues pour les habiletés expliqueraient l'accroissement qu'on a observé dans la dispersion des gains des hommes au Canada. [source] Cholesterol metabolism in 8 to 12-year-old children born preterm or at termACTA PAEDIATRICA, Issue 5 2003M Mortaz Studies in animals have indicated that cholesterol metabolism is susceptible to manipulation by diet and growth in early life. In humans, low birthweight has been associated with increased risk of coronary heart disease. Aim: To establish whether plasma lipids and indicators of cholesterol absorption, synthesis and breakdown differ in children born preterm and at term. Methods: Plasma total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triacylglycerols, apolipoprotein A1, apolipoprotein B, lathosterol (indicator of cholesterol synthesis), campesterol (indicator of cholesterol absorption), 7-, hydroxycholesterol (indicator of cholesterol breakdown) were measured in up to 407 children born preterm and 36 children born at term. Results: Children born preterm had lower cholesterol synthesis (p= 0.002) and lower cholesterol breakdown (p < 0.001) than those born at term, but their plasma cholesterol concentration was not significantly different. After adjusting for current size, birthweight and gestational age were significantly related to plasma lathosterol and 7-, hydroxycholesterol. However, when both birthweight and gestational age were adjusted, only gestational age remained significant. There were no significant differences in plasma campesterol between the two groups. Conclusion: Being born preterm may have a long-term effect on cholesterol metabolism in children 8,12 y later. Those born prematurely had lower cholesterol synthesis and breakdown, but their plasma cholesterol concentration was similar at this age. These parameters need to be studied in older cohorts. [source] Rectal cancer in young adults: a series of 102 patients at a tertiary care centre in IndiaCOLORECTAL DISEASE, Issue 5 2009J. Nath Abstract Objective, Rectal cancer in young patients is uncommon. There is little information on rectal cancer in young adults in India. The aim of this study was to determine the relative incidence of rectal cancer in young patients in India and identify any differences in histological grade and pathological stage between younger and older cohorts. Method, All adult patients presenting at a tertiary colorectal unit with primary rectal adenocarcinoma between September 2003 and August 2007 were included. Patients were divided into two groups: 40 years and younger, and older than 40 years. Details regarding patient demographics, preoperative assessment, management and tumour grade and stage were obtained from a prospectively maintained database. Results, One hundred and two of 287 patients (35.5%) were 40 or younger at presentation. Younger patients were more likely to present with less favourable histological features (52.0%vs 20.5% (P < 0.001)) and low rectal tumours (63.0%vs 50.0%) (P = 0.043), but were equally likely to undergo curative surgery compared to the older group (P = 0.629). Younger patients undergoing surgery had a higher pathological T stage (T0,2 18.9%, T3 62.3%, T4 19.7%vs 34.5%, 56.0%, 9.5%) (P = 0.027) and more advanced pathological N stage (N0 31.1%, N1 41.0%, N2 27.9%vs 53.4%, 26.7%, 17.2%) (P = 0.014). Conclusion, The relative number of young patients with rectal cancer in this Indian series is higher than figures reported in western populations. The reasons for this are not clear. The histopathological features of rectal tumours in young patients in this study are consistent with similar studies in Western populations. [source] | ||||||||||||||||||||||