Extensive Information (extensive + information)

Distribution by Scientific Domains


Selected Abstracts


Smoking, nicotine dependence and mental health among young adults: a 13-year population-based longitudinal study

ADDICTION, Issue 1 2009
Willy Pedersen
ABSTRACT Aims To investigate prospectively the associations between daily smoking and nicotine dependence and anxiety, depression and suicide attempts. Methods Data were from the Young in Norway Longitudinal Study. A population-based sample (n = 1501) was followed for 13 years from ages 13,27 years. Data were gathered on smoking patterns and nicotine dependence; and depression, anxiety and parasuicide. Extensive information on socio-demographic factors, parental and family conditions, parental rearing practices, educational career, conduct problems, alcohol problems and use of illegal substances was also collected. Results Young adults who were nicotine-dependent had clearly elevated rates of anxiety, depression and parasuicide. These rates declined after controlling for a previous history of mental health problems and potential confounding factors. After adjustment, nicotine dependence was still associated with anxiety, depression and parasuicide. There was also a significant association with later depression in the group of non-dependent daily smokers. Measures of reduced mental health did not predict later smoking initiation or the development of nicotine dependence. Conclusions Mental health was reduced more seriously in nicotine-dependent smokers than in non-dependent smokers. These findings are consistent with the hypothesis that smoking, in particular nicotine dependence, influences mental health. [source]


Cannabis and crime: findings from a longitudinal study

ADDICTION, Issue 1 2010
Willy Pedersen
ABSTRACT Aim To examine the association between cannabis use during adolescence and young adulthood, and subsequent criminal charges. Methods Data were obtained from the Young in Norway Longitudinal Study. A population-based sample (n = 1353) was followed from 13 to 27 years of age. Data were gathered on cannabis use, alcohol consumption and alcohol problems, and use of other illegal substances such as amphetamines, cocaine and opiates. In addition, extensive information on socio-demographic, family and personal factors was collected. This data set was linked to individual-level information from official Norwegian crime statistics. Findings We found robust associations between cannabis use and later registered criminal charges, both in adolescence and in young adulthood. These associations were adjusted for a range of confounding factors, such as family socio-economic background, parental support and monitoring, educational achievement and career, previous criminal charges, conduct problems and history of cohabitation and marriage. In separate models, we controlled for alcohol measures and for use of other illegal substances. After adjustment, we still found strong associations between cannabis use and later criminal charges. However, when eliminating all types of drug-specific charges from our models, we no longer observed any significant association with cannabis use. Conclusions The study suggests that cannabis use in adolescence and early adulthood may be associated with subsequent involvement in criminal activity. However, the bulk of this involvement seems to be related to various types of drug-specific crime. Thus, the association seems to rest on the fact that use, possession and distribution of drugs such as cannabis is illegal. The study strengthens concerns about the laws relating to the use, possession and distribution of cannabis. [source]


Modelling the effects of loss of soil biodiversity on ecosystem function

GLOBAL CHANGE BIOLOGY, Issue 1 2002
H. W. Hunt
Abstract There are concerns about whether accelerating worldwide loss of biodiversity will adversely affect ecosystem functioning and services such as forage production. Theoretically, the loss of some species or functional groups might be compensated for by changes in abundance of other species or functional groups such that ecosystem processes are unaffected. A simulation model was constructed for carbon and nitrogen transfers among plants and functional groups of microbes and soil fauna. The model was based on extensive information from shortgrass prairie, and employed stabilizing features such as prey refuges and predator switching in the trophic equations. Model parameters were derived either from the literature or were estimated to achieve a good fit between model predictions and data. The model correctly represented (i) the major effects of elevated atmospheric CO2 and plant species on root and shoot biomass, residue pools, microbial biomass and soil inorganic nitrogen, and (ii) the effects on plant growth of manipulating the composition of the microbial and faunal community. The model was evaluated by comparing predictions to data not used in model development. The 15 functional groups of microbes and soil fauna were deleted one at a time and the model was run to steady state. Only six of the 15 deletions led to as much as a 15% change in abundance of a remaining group, and only two deletions (bacteria and saprophytic fungi) led to extinctions of other groups. Functional groups with greater effect on abundance of other groups were those with greater biomass or greater number of consumers, regardless of trophic position. Of the six deletions affecting the abundance of other groups, only three (bacteria, saprophytic fungi, and root-feeding nematodes) caused as much as 10% changes in indices of ecosystem function (nitrogen mineralization and primary production). While the soil fauna as a whole were important for maintenance of plant production, no single faunal group had a significant effect. These results suggest that ecosystems could sustain the loss of some functional groups with little decline in ecosystem services, because of compensatory changes in the abundance of surviving groups. However, this prediction probably depends on the nature of stabilizing mechanisms in the system, and these mechanisms are not fully understood. [source]


Modelling ecological half-lives for radiocaesium in Norwegian brown trout populations

JOURNAL OF APPLIED ECOLOGY, Issue 1 2000
Dag O. Hessen
Summary 1.,Models of ecological half-life may be valuable and cost-effective predictive tools for authorities setting restrictions on human consumption of freshwater fish after environmental releases of radioactivity. This work aimed to validate such a model for radioactive caesium (134Cs and 137Cs) in brown trout Salmo trutta populations. Data were drawn from lakes with a wide variability in abiotic and biotic factors and initial caesium load. 2.,In Norway, the highest fallout (more than 150 kBq m,2 of 137Cs) from the Chernobyl accident occurred in Oppland county, in south central Norway. Radioactivity was measured in more than 1800 samples of brown trout in nearly 100 localities in this region during 1986,95. 3.,The back-calculated maximum initial radioactivity on 1 January 1987 showed a strong regional variability (range 443,13 370; average 3855 Bq kg,1). Large variation in initial radioactivity was also recorded on a local scale (within 50 km). 4.,The ecological half-life model for caesium in brown trout populations for 1987,94/95 gave a close fit to real data from all localities with sufficient time series. Predicted half-lives ranged from 1·2 to 4·2 years (average 2·5) but 95% confidence limits were narrow (2·7 and 2·3 years). 5.,The overall variability in radioactivity levels over time was almost entirely related to the initial load and, with few exceptions, 88% of the changes in radioactivity was explained by the simple regression model. Modest variability in ecological half-life was not correlated with initial activity, and no clear effects of water quality or season could be detected. For most lakes, levels of radioactivity in brown trout appeared to be predictable, with high accuracy after a fallout event, without extensive information on population ecology and water quality. However, more detailed work may be required to assess patterns within individual lakes. [source]


Relocated Citizens' Perceptions and Attitudes Regarding Indoor Application of Toxic Agricultural Pesticides

JOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2000
Olurominiyi O. Ibitayo
This study investigates the viewpoints of relocated citizens regarding the effects of relocation, perceptions of the potential hazards of indoor application of a toxic agricultural pesticide , methyl parathion , and the efficacy of the risk information emphasizing the adverse health effects of this inappropriate use of the pesticide. The surveyed citizens were those relocated because the levels of the pesticide contaminant in their homes were high. Despite the extensive information , through the mass media and face-to-face warnings and activities such as assessment of contamination levels, decontamination of homes and relocation , the respondents, regardless of race, consistently perceived relatively low levels of risks from the indoor application of methyl parathion. The disruption of family life, loss of peace of mind and the loss of contaminated property were the most mentioned problems caused by the relocation. In contrast to past research, the disruption of social ties or networks was hardly mentioned. The results of this study suggest that the perceived personal benefits of home-use of methyl parathion, and the voluntariness and controllability of exposure may have been the overriding factors of the respondents' risk perception, more than the clarity, content, consistency, and credibility of the risk information. The fact that the relocation was temporary must have contributed to the low level of importance attached by the respondents to the disruption of social ties as one of the adverse effects of the relocation. [source]


Condensation routes to polyaniline and its analogs

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2007
H. K. Hall
Abstract To obtain polyanilines which are more structurally perfect than those obtainable by the oxidation of anilines, polycondensation procedures were investigated. Model reactions gave extensive information about yields and about the physical properties of the putative structural polymer units. Condensation of anthraquinones with aromatic diamines using titanium tetrachloride and the unique base, 1,4-diazabicyclo-[2.2.2]-octane Dabco, gave high molecular weight orange polyquinonimines. Alkoxy groups on the anthraquinone ring aided solubility and molecular weight, and appropriately positioned alkoxy groups afforded stereoregular polymers. A bisthiophene benzoquinone also polymerized successfully. Application of the same procedure to 2,5-dimethyl- p -benzoquinone gave stereoregular poly(arylene benzoquinonimines), close analogs of pernigrani line. The factors causing problems in achieving high yields and high molecular weight were identified. Recent synthetic developments in this field are discussed. Reduction of the obtained polyquinonimines proceeded smoothly to the leucoemeraldine analogs. Unlike the results from pernigraniline obtained by oxidative polymerization, no evidence for the formation of the electrically conductive emeraldine form was obtained. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4751,4763, 2007 [source]


Engagement in occupations among men and women with schizophrenia

OCCUPATIONAL THERAPY INTERNATIONAL, Issue 2 2006
Ulrika Bejerholm
Abstract This study describes engagement in daily occupations of 10 women and 10 men with schizophrenia. A 24-hour diary of time use and interview were used and analysed by content analysis. Three levels of occupational engagement were identified; (1) mainly disengaged throughout the day, (2) disengaged during some part of the day, and (3) largely engaged in occupations during the day. Each level of occupational engagement was related to a daily rhythm and a sense of meaning. The results of the content analysis showed that levels of engagement ranged from performing mostly quiet activities, alone, with little sense of meaning, to engaging in meaningful occupations that involved social interactions. In general female participants preferred activities in their home environment while males preferred activities outside their home environment. Although this study was limited by geographic and cultural boundaries, as well by the sample size, the results showed that being diagnosed as having schizophrenia does not necessarily mean having an impoverished lifestyle. Thus, it is important for occupational therapists to identify these variations in engagement in order to have a realistic point of departure in the evaluation process and in forming a therapeutic alliance with the client. In future research, methods need to be developed that can gather extensive information on how occupational engagement is related to health and well-being in individuals diagnosed with schizophrenia. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Data collected on maternal dietary exposures in the Danish National Birth Cohort

PAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2007
Sjúrdur Fródi Olsen
Summary Recent research suggests that the diet consumed in, or shortly before, pregnancy can potentially lead to maldevelopment and diseases in the offspring, which may become apparent at any time from the embryonic stage until old age. For example, maternal diet may affect the chance of twinning (and associated complications), malformation risk, brain development, and the offspring's fecundity and risk of contracting cardiovascular dieases and cancer in adult life. Prospectively designed longitudinal studies with sufficient size and data quality are much needed to substantiate or refute these hypotheses. At present, the Danish National Birth Cohort is likely to be the largest epidemiological database containing extensive information on maternal dietary exposures. By October 2002, 100 000 women had been recruited in early pregnancy, for long-term follow-up of themselves and their offspring. The present paper details the information available in the database on early nutritional exposures with emphasis on maternal dietary intake. We also present distributions of selected nutritional exposures. [source]


Signal generation and clarification: use of case,control data

PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 3 2001
David W. Kaufman ScD
Abstract Case-control surveillance systems are useful for ,signal' generation, i.e., signaling potential previously unidentified adverse effects of drugs. Two systems currently in operation, the Slone Epidemiology Unit's Case-Control Surveillance and the Birth Defects Study, have monitored drug effects since 1976. With extensive information on the diagnoses and covariates, the systems have the capacity to carry out in-depth analyses in which the outcome measure is more specifically defined and in which confounding is controlled, thus reducing the possibility of false alarms. Copyright © 2001 John Wiley & Sons, Ltd. [source]


From Adjuvant Therapy to Breast Cancer Prevention: BCPT and STAR

THE BREAST JOURNAL, Issue 3 2001
Barbara K. Dunn MD
Abstract: The continued widespread prevalence of breast cancer supports placing a high priority on research aimed at its primary prevention, particularly among women who are at increased risk for developing this disease. The suggestion of potential agents for the primary chemoprevention of breast cancer evolved out of the treatment setting. Extensive experience with tamoxifen, a first-generation selective estrogen receptor modulator (SERM) showing efficacy, first, in the treatment of advanced breast cancer and, subsequently, as adjuvant therapy for early stage disease established the safety of this agent. Cumulative data from multiple adjuvant studies documented the efficacy of tamoxifen in reducing second primary breast cancers in the contralateral breast, supporting its potential as a chemopreventive agent for breast cancer. The safety and second primary data on tamoxifen, together with extensive information on its pharmacokinetics, metabolism, and antitumor effects, as well as its potentially beneficial effects on lipid metabolism and osteoporosis, led the National Surgical Adjuvant Breast and Bowel Project (NSABP) to select tamoxifen for testing in the first prospective randomized phase III trial of the efficacy of a chemopreventive agent for preventing breast cancer in women at increased risk of the disease. Accordingly, in 1992 the NSABP started the Breast Cancer Prevention Trial (P-1) in which 13,388 women 35 years of age who were at increased risk of breast cancer according to Gail model risk factors [family history, age, and personal history (i.e., age at first birth, age at menarche, previous breast biopsies)] were randomized to tamoxifen 20 mg/day or placebo for 5 years. Through 69 months of follow-up tamoxifen reduced the risk of invasive breast cancer, primarily estrogen receptor-positive tumors, by 49% (two-sided p < 0.00001). Tamoxifen reduced the risk of noninvasive breast cancer by 50% (two-sided p < 0.002). In addition, tamoxifen reduced fractures of the hip, radius, and spine, but it had no effect on the rate of ischemic heart disease. As previously shown, the rates of endometrial cancer and vascular events increased with tamoxifen. With the P-1 results establishing tamoxifen as the standard of care for the primary chemoprevention of breast cancer in high-risk women, concern over the side effects of tamoxifen has prompted a continuing search for an agent that displays a more desirable efficacy/toxicity profile. Raloxifene, a second-generation SERM approved for the prevention of osteoporosis in postmenopausal women, displays antiestrogenic properties in the breast and possibly the endometrium, and estrogenic effects in the bone and on the lipid profile, suggesting it as a candidate for comparison with the chemopreventive standard, tamoxifen. Raloxifene will be compared to tamoxifen in an equivalency trial, the Study of Tamoxifen and Raloxifene (STAR) NSABP P-2, which began in July 1999 at almost 500 centers in North America. The plan is to randomize 22,000 postmenopausal women 35 years of age at increased risk of breast cancer by Gail criteria to tamoxifen 20 mg/day or raloxifene 60 mg/day for 5 years. Study endpoints include invasive and noninvasive breast cancer, cardiovascular disease, endometrial cancer, bone fractures, and vascular events. [source]


Effects of Viscous Dissipation on Heat Transfer between an Array of Long Circular Cylinders and Power Law Fluids

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 6 2007
R. P. Chhabra
Abstract The free surface model has been combined with the equations of motion and of thermal energy to investigate the role of viscous dissipation on heat transfer between banks of long cylinders and power law (shear-thinning and shear-thickening) fluids. The equations of motion cast in the stream function/vorticity formulation have been solved numerically using a second-order accurate finite difference method to obtain extensive information on the behaviour of local and surface-averaged Nusselt numbers over a range of Reynolds numbers 1 , 500, for a wide range of power law indices (0.4 , n , 2.0), Brinkman numbers (0 , Br , 5) and Prandtl numbers (Pr = 1, 1000) at two representative solid volume fractions corresponding to the porosities of e = 0.4 and 0.9. Two different thermal boundary conditions are considered at the cylinder surface: constant temperature (CT) and constant heat flux (CHF). The results presented herein provide a fundamental knowledge about the influence of viscous dissipation on the heat transfer characteristics. The results reported herein further show that the effect of Brinkman number on heat transfer is strongly conditioned by the thermal boundary condition, Prandtl number and the power law index. On a combiné le modèle de surface libre aux équations de mouvement et de transfert de chaleur afin d'étudier le rôle de la dissipation visqueuse sur le transfert de chaleur entre des rangées de cylindres longs pour des fluides de loi de puissance (rhéofluidifiants et rhéoépaississants). Les équations de mouvement formulées en fonction de courant/vorticité ont été résolues numériquement à l'aide d'une méthode de différences finies du second ordre, afin d'obtenir des informations détaillées sur le comportement des nombres de Nusselt locaux et moyennés en surface pour une gamme de nombres de Reynolds compris entre 1 et 500, une large gamme d'indices de loi de puissance (0,4 , n , 2,0), de nombres de Brinkman (0 , Br , 5) et de nombres de Prandtl (Pr = 1,1000) à deux fractions de volume de solides correspondant à une porosité de e = 0,4 et 0,9. Deux conditions aux limites thermiques ont été considérées à la surface du cylindre: la température constante (CT) et le flux de chaleur constant (CHF). Les résultats présentés permettent de rendre compte de l'influence de la dissipation visqueuse sur les caractéristiques du transfert de chaleur et l'effet du nombre de Brinkman sur le transfert de chaleur qui est fortement influencé par la condition aux limites thermique, le nombre de Prandtl et l'indice de loi de puissance. [source]


Intergenerational Welfare Participation in New Zealand

AUSTRALIAN ECONOMIC PAPERS, Issue 3 2003
Tim Maloney
New Zealand panel data, which provide extensive information on the benefit histories of parents and their children, are used to estimate an intergenerational correlation coefficient in social welfare dependency. Recent estimation techniques for addressing issues of measurement error are applied to this analysis. The long-term benefit histories of parents and instrumental variable techniques provide useful lower and upper-bound estimates of the true intergenerational correlation. Our results suggest that the true correlation coefficient between the welfare participation of parents and their offspring is somewhere between one-third and two-thirds, but probably much closer to the lower limit in this range. Approximately one-quarter of this effect appears to operate through the lower educational attainment of children reared in families receiving social welfare benefits. [source]


Alterations of intraretinal layers in acute central serous chorioretinopathy

ACTA OPHTHALMOLOGICA, Issue 5 2009
Christian Ahlers
Abstract. Purpose:, Optical coherence tomography (OCT) is restricted by its low scanning speed and limited resolution. High-definition raster-scanning OCT (HD-OCT) was used to evaluate changes in retinal microstructure in patients with acute central serous chorioretinopathy (CSCR) and to find new morphological features. Methods:, Eighteen patients with subretinal fluid accumulation caused by acute CSCR were imaged in a cross-sectional study design. High-speed frequency-domain HD-OCT was used to image an area of 6 × 6 mm in the macular retina. Three-dimensional analyses were performed using en-face imaging and section analysis of single HD-OCT scans. Results:, Detailed information about fluid accumulation can be obtained in all compartments. Discrete changes in reflectivity are visualized within the outer nuclear or plexiform layers in > 90% of patients. Subretinal fluid appears as a dome-shaped pool of fluid and is not associated with a loss of photoreceptor layer integrity. Deposits are demarcated beneath the outer cone segments. Multiple small pigment epithelial detachments are present in > 60% of patients. Conclusions:, High-definition OCT provides extensive information regarding precise topographic and layer-specific localization of discrete morphological changes. Along with well-known changes in the retinal microstructure, hyper-reflectivity can be imaged in the outer nuclear or plexiform layers and may represent intraretinal changes indicating the presence of subretinal pathologies or retinal maladjustment caused by the underlying pathology. [source]