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51.
The aim of this study is to investigate the effects of exposure to aluminium on the cognitive sphere in a group of welders. Given the intrinsic complexity of the neurocognitive sphere, three different psychomotor variables were used for its investigation allowing the resulting problem to be naturally modelized into a multivariate framework and solved by a nonparametric combination of permutation tests (NPC test). In order to make the treated and control groups comparable, we also stratified the samples on the basis of a risk index that estimates the combined action of biological age and exposure time. Despite the fact that studies in the literature have reached conflicting results, our study highlights a significant drop in attention and memory performances in individuals exposed to aluminium. Finally, we identify a global criterion that summarises the information on the neurocognitive state by applying the nonparametric combination of dependent rankings method (NPC ranking).  相似文献   
52.
The theory of intertemporal consumption choice makes sharp predictions about the evolution of the entire distribution of household consumption, not just about its conditional mean. In the paper, we study the empirical transition matrix of consumption using a panel drawn from the Bank of Italy Survey of Household Income and Wealth. We estimate the parameters that minimize the distance between the empirical and the theoretical transition matrix of the consumption distribution. The transition matrix generated by our estimates matches remarkably well the empirical matrix, both in the aggregate and in samples stratified by education. Our estimates strongly reject the consumption insurance model and suggest that households smooth income shocks to a lesser extent than implied by the permanent income hypothesis. (JEL: D52, D91, I30)  相似文献   
53.
Statistical Methods & Applications - A measure of interrater absolute agreement for ordinal scales is proposed capitalizing on the dispersion index for ordinal variables proposed by Giuseppe...  相似文献   
54.
The aim of the present study was to explore the dimensions of alexithymia and attachment styles in a group of disordered gamblers and to evaluate the relationship between alexithymia, attachment styles, and the severity of gambling disorder. Sixty disordered gamblers diagnosed according to the diagnostic and statistical manual-5 filled out the Kurzfragebogen zum Glücksspielverhalten, the 20-Item Toronto Alexithymia Scale, and the Experiences in Close Relationships-Revised. Approximately 70 % of the sample displayed ‘intermediate’ and ‘severe’ gambling severity levels on the Kurzfragebogen zum Glücksspielverhalten, and 77 % showed ‘high’ or ‘borderline’ levels of alexithymia on the Toronto Alexithymia Scale (mean = 56.40). Regarding attachment styles, 70 % of the sample displayed an ‘insecure’ attachment, with a particularly high prevalence of the ‘fearful’ style (26.66 %). A linear regression analysis revealed that only the anxiety dimension of the Experiences in Close Relationships questionnaire predicted the severity of gambling. Our data appear to confirm that gambling disorder is characterised by emotional and relational dysregulation, and that pathological gambling behaviours may serve as external regulators of internal undifferentiated emotional states.  相似文献   
55.
Social Indicators Research - Providing unpaid informal care to someone who is ill or disabled is a common experience in later life. While a supportive and potentially rewarding role, informal care...  相似文献   
56.
An impounded estuarine marsh scheduled for restoration in 2003 and three nearby unimpounded marshes (Spartina alterniflora, S. patens/Iva frutescens, and Phragmites australis) in highly urbanized NY/NJ Harbor were studied to assess the impact of impoundment on marsh structure and function and to identify trajectories of ecosystem change following removal of the levee. Aboveground biomass was greater in the Phragmites and S. alterniflora marshes (706–809 g/m2) as compared to the S. patens/I. frutescens and impounded marshes (378–588 g/m2). Macro-organic matter (0–30 cm) was similar across all marshes (7452–9212 g/m2). The S. patens/Iva frutescens marsh had the lowest aboveground biomass, but contained more plant species (2.8 species/0.25 m2) and greater species diversity (H = 1.33) than the other marshes (1.3–2.0 species/0.25 m2, H = 0.16–0.78). Rates of sediment and nutrient accumulation were lower in the impounded marsh (335 g sediment/m2/yr, 97 g C/m2/yr, 6.5 g N/m2/yr, and 0.9 g P/m2/yr) than in the reference marshes (422–1515 g sediment/m2/yr; 111–160 g C/m2/yr; 7–10 g N/m2/yr; 1.6–2.8 g P/m2/yr). Our results indicate that the impounded marsh does not contain the high species diversity of the high marsh, nor does it provide the same level of functions as naturally inundated marshes. Reintroduction of tidal inundation to the impounded marsh will enhance water quality benefits and favor development of S. alterniflora salt marsh community structure.  相似文献   
57.
A prognostic index (PI) is usually derived from a regression model as a weighted mean of the covariates, with weights (partial scores) proportional to the parameter estimates. When a PI is applied to patients other than those considered for its development, the issue of assessing its validity on the new case series is crucial. For this purpose, Van Houwelingen (2000) proposed a method of validation by calibration, which limits overfitting by embedding the original model into a new one, so that only a few parameters will have to be estimated. Here we address the problem of PI validation and revision with the above approach when the PI has classification purposes and it represents the linear predictor of a Weibull model, derived from an accelerated failure time parameterization instead of a proportional hazards one, as originally described by Van Houwelingen. We show that the Van Houwelingen method can be applied in a straightforward manner, provided that the parameterization originally used in the PI model is appropriately taken into account. We also show that model validation and revision can be carried out by modifying the cut-off values used for prognostic grouping without affecting the partial scores of the original PI. This procedure can be applied to simplify the clinician's use of an established PI for classification purposes.  相似文献   
58.
59.
This paper advances the hypothesis that for a child to feel safe and to learn at school certain psychological conditions must be met. These conditions are described using concepts derived from psychoanalytic research and include; a background of SAFETY and a feeling of WELL BEING derived from a healthy ego with perceptual skills appropriate to the task, a HOLDING environment of adults who can respond appropriately to the child's developmental needs, an environment that provides CONTAINMENT and helps children process negativity in relationships, processes that help children regulate affect, value relationships, and leam to mentalise, in a SECURE ATTACHMENT experience, and finally, supports that encourage children to function as responsible members of a community organized as an OPEN SOCIAL SYSTEM.  相似文献   
60.
In this paper we aim at assessing the outcomes of the 2007 Italian reform of the complementary social security scheme and at identifying the determinants behind them. The reform provided workers with relevant incentives to switch the investment of about 7 per cent of their gross yearly wages from a firm‐managed scheme (which took the form of a termination indemnity payment, the Trattamento di Fine Rapporto scheme) to an external pension fund. We provide a theoretical framework to model the workers' problem of choosing between these two different forms of complementary social security schemes and we then perform an agent‐based simulation taking into account all the details of the reform. Differently from previous contributions, we stress the impact that the investment decision has on the financial health of firms and, consequently, on workers' employment stability. Our simulations are able to replicate the Italian data in terms of adhesion rates to complementary social security and also to identify some of the key determinants of that outcome, such as fiscal incentives, individual preferences, the working of both the Italian labour and the financial markets and the productive structure of the Italian economy.  相似文献   
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