81 resultados para 13077-021


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Everyday functioning is an important outcome for studies of the developmental psychopathology of adolescence. An unbiased, well-validated, and easy-to-use instrument to specifically assess normal adolescent functioning is not yet available. The current study aimed to introduce and validate the Multidimensional Adolescent Functioning Scale

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The goal of this paper is to undertake a panel data investigation of long-run Granger causality between electricity consumption and real GDP for seven panels, which together consist of 93 countries. We use a new panel causality test and find that in the long-run both electricity consumption and real GDP have a bidirectional Granger causality relationship except for the Middle East where causality runs only from GDP to electricity consumption. Finally, for the G6 panel the estimates reveal a negative sign effect, implying that increasing electricity consumption in the six most industrialised nations will reduce GDP. © 2010 Elsevier Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Precise and reliable modelling of polymerization reactor is challenging due to its complex reaction mechanism and non-linear nature. Researchers often make several assumptions when deriving theories and developing models for polymerization reactor. Therefore, traditional available models suffer from high prediction error. In contrast, data-driven modelling techniques provide a powerful framework to describe the dynamic behaviour of polymerization reactor. However, the traditional NN prediction performance is significantly dropped in the presence of polymerization process disturbances. Besides, uncertainty effects caused by disturbances present in reactor operation can be properly quantified through construction of prediction intervals (PIs) for model outputs. In this study, we propose and apply a PI-based neural network (PI-NN) model for the free radical polymerization system. This strategy avoids assumptions made in traditional modelling techniques for polymerization reactor system. Lower upper bound estimation (LUBE) method is used to develop PI-NN model for uncertainty quantification. To further improve the quality of model, a new method is proposed for aggregation of upper and lower bounds of PIs obtained from individual PI-NN models. Simulation results reveal that combined PI-NN performance is superior to those individual PI-NN models in terms of PI quality. Besides, constructed PIs are able to properly quantify effects of uncertainties in reactor operation, where these can be later used as part of the control process. © 2014 Taiwan Institute of Chemical Engineers.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we propose a GARCH-based unit root test that is flexible enough to account for; (a) trending variables, (b) two endogenous structural breaks, and (c) heteroskedastic data series. Our proposed model is applied to a range of time-series, trending, and heteroskedastic energy variables. Our two main findings are: first, the proposed trend-based GARCH unit root model outperforms a GARCH model without trend; and, second, allowing for a time trend and two endogenous structural breaks are important in practice, for doing so allows us to reject the unit root null hypothesis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The worldwide prevalence of leishmaniasis is increasing because of ecologic changes and increased medical profession awareness. Furthermore, solitary cases have been recently reported in Western countries. The authors describe the epidemiology, mode of transmission, and diagnosis of leishmaniasis and present 4 oral cases treated with systemic, localized, or combined therapy. The authors suggest that clinicians should maintain a high index of suspicion for atypical, resistant, oral and perioral lesions in individuals with a history of traveling in certain geographic regions. After diagnosis, treatment should be determined jointly by experts from the fields of oral and maxillofacial surgery, oral medicine, and dermatology based on leishmaniasis species and clinical presentation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Previous studies on handedness have often reported functional asymmetries in corticomotor excitability (CME) associated with voluntary movement. Recently, we have shown that the degree of post-exercise corticomotor depression (PED) and increase in short-interval cortical inhibition (SICI) after a repetitive finger movement task was less when the task was performed at a maximal voluntary rate (MVR) than when it was performed at a submaximal sustainable rate (SR). In the current study, we have compared the time course of PED and SICI in the dominant (DOM) and nondominant (NDOM) hands after an MVR and SR finger movement task to determine the influence of hand dominance and task demand. We tracked motor-evoked potential (MEP) amplitude from the first dorsal interosseous muscle of the DOM and NDOM hand for 20 min after a 10-s index finger flexion-extension task at MVR and SR. For all hand-task combinations, we report a period of PED and increased SICI lasting for up to 8 min. We find that the least demanding task, one that involved index finger movement of the DOM hand at SR, was associated with the greatest change in PED and SICI from baseline (63.6±5.7% and 79±2%, P<0.001, PED and SICI, respectively), whereas the most demanding task (MVR of the NDOM hand) was associated with the least change from baseline (PED: 88.1±3.6%, SICI: 103±2%; P<0.001). Our findings indicate that the changes in CME and inhibition associated with repetitive finger movement are influenced both by handedness and the degree of demand of the motor task and are inversely related to task demand, being smallest for an MVR task of the NDOM hand and greatest for an SR task of the DOM hand. The findings provide additional evidence for differences in neuronal processing between the dominant and nondominant hemispheres in motor control.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study aimed to investigate the association of obsessive-compulsive symptoms with clinical and neurocognitive features in patients with schizophrenia. This study enrolled 163 people with schizophrenia who were receiving risperidone monotherapy. Comorbid obsessive-compulsive symptoms were assessed using the Yale-Brown Obsessive-Compulsive Scale, and subjects with a score≥10 constituted the obsessive-compulsive symptom group (n=30, 18.4%). The learning index was significantly higher in patients with obsessive-compulsive symptoms than in those without such symptoms after adjusting for age, stage (early and chronic), duration of illness, and CDSS score. However, there was no significant interaction between obsessive-compulsive symptoms and stage of illness. Scores on Positive and Negative Syndrome Scale, Calgary Depression Scale for Schizophrenia, and Beck Depression Inventory were significantly higher in the obsessive-compulsive symptom group. In addition, the Subjective Well-being under Neuroleptic Treatment score was significantly lower in the obsessive-compulsive symptom group. In conclusion, comorbid obsessive-compulsive symptoms in patients with schizophrenia were associated with a higher learning ability without a significant interaction with stage of illness. However, schizophrenia patients with obsessive-compulsive symptoms had more severe psychotic and depressive symptoms and poorer quality of life.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study aimed to investigate the association of obsessive-compulsive symptoms with clinical and neurocognitive features in patients with schizophrenia. This study enrolled 163 people with schizophrenia who were receiving risperidone monotherapy. Comorbid obsessive-compulsive symptoms were assessed using the Yale-Brown Obsessive-Compulsive Scale, and subjects with a score ≥ 10 constituted the obsessive-compulsive symptom group (n=30, 18.4%). The learning index was significantly higher in patients with obsessive-compulsive symptoms than in those without such symptoms after adjusting for age, stage (early and chronic), duration of illness, and CDSS score. However, there was no significant interaction between obsessive-compulsive symptoms and stage of illness. Scores on Positive and Negative Syndrome Scale, Calgary Depression Scale for Schizophrenia, and Beck Depression Inventory were significantly higher in the obsessive-compulsive symptom group. In addition, the Subjective Well-being under Neuroleptic Treatment score was significantly lower in the obsessive-compulsive symptom group. In conclusion, comorbid obsessive-compulsive symptoms in patients with schizophrenia were associated with a higher learning ability without a significant interaction with stage of illness. However, schizophrenia patients with obsessive-compulsive symptoms had more severe psychotic and depressive symptoms and poorer quality of life.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Broad antifungal structure-activity relationships governing epoxy-endoperoxides 2 and 3 and their parent endoperoxides 1 are reported. Their inhibitory activity against Candida albicans in conjunction with hemolytic activity and/or growth inhibition of cultured mammalian cells are reported. This information provided guidance for the further development of endoperoxide and epoxy-endoperoxides as topical antifungal agents.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Abstract We report that a prestressing technique similar to that traditionally used in prestressed concrete can improve the mechanical performance of flax fibre spun yarn reinforced polymer-matrix composites. Prestressing a low twist yarn not only introduces tension to the constituent fibres and compressive stress to the matrix similar as in prestressed concretes, but also causes changes to the yarn structure that lead to the rearrangement of fibres within the yarn. Prestressing increases the fibre packing density in yarn, causes fibre straightening, and reduces fibre obliquity in yarn (improved fibre alignment along yarn axis). All these changes contribute positively to the mechanical properties of the natural fibre yarn reinforced composites. Crown

Relevância:

10.00% 10.00%

Publicador:

Resumo:

ABSTRACT
This paper addresses the strain ageing effects on the mechanical properties of the partially damaged structural mild steel. Since repairing partly damaged structures may not occur immediately, the strain ageing effect can significantly influence the structural behaviour. The changes due to this effect have not so far been considered in the civil engineering design guidelines. In order to investigate strain ageing effects, two-stage experimental tests are carried out on the mild-steel specimens. In the first stage, partial damage is made using quasi-static loading. During the second stage, the strength and ductility of the specimens are examined after 2 and 7 days ‘ageing’ at room temperature and the results are compared with the corresponding no-age samples. The microstructure of the specimens is examined using scanning electron microscopy (SEM). To illustrate the effect of strain ageing on the global behaviour of steel structures, a numerical example is provided in which strain ageing impacts on loading capacity and deflection of a steel beam. Finally, the stress–strain relation of partially damaged mild-steel material incorporating strain ageing effects is expressed by calibrating the parameters of Ramberg–Osgood model.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

To better understand the effects of prolonged bed-rest in women, 24 healthy women aged 25 to 40 years participated in 60-days of strict 6° head-down tilt bed-rest (WISE-2005). Subjects were assigned to either a control group (CON, n=8) which performed no countermeasure, an exercise group (EXE, n=8) undertaking a combination of resistive and endurance training or a nutrition group (NUT, n=8), which received a high protein diet. Using peripheral quantitative computed tomography (pQCT) and dual X-ray absorptiometry (DXA), bone mineral density (BMD) changes at various sites, body-composition and lower-leg and forearm muscle cross-sectional area were measured up to 1-year after bed-rest. Bone loss was greatest at the distal tibia and proximal femur, though losses in trabecular density at the distal radius were also seen. Some of these bone losses remained statistically significant one-year after bed-rest. There was no statistically significant impediment of bone loss by either countermeasure in comparison to the control-group. The exercise countermeasure did, however, reduce muscle cross-sectional area and lean mass loss in the lower-limb and also resulted in a greater loss of fat mass whereas the nutrition countermeasure had no impact on these parameters. The findings suggest that regional differences in bone loss occur in women during prolonged bed-rest with incomplete recovery of this loss one-year after bed-rest. The countermeasures as implemented were not optimal in preventing bone loss during bed-rest and further development is required.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND AND AIM: There is limited data on the effects of inactivity (prolonged bed-rest) on parameters of endocrine and metabolic function; we therefore aimed to examine changes in these systems during and after prolonged (56- day) bed-rest in male adults. SUBJECTS AND METHODS: Twenty healthy male subjects underwent 8 weeks of strict bed-rest and 12 months of follow-up as part of the Berlin Bed Rest Study. Subjects were randomized to an inactive group or a group that performed resistive vibration exercise (RVE) during bed-rest. All outcome parameters were measured before, during and after bed-rest. These included body composition (by whole body dual X-ray absorptiometry), SHBG, testosterone (T), estradiol (E2), PRL, cortisol (C), TSH and free T3 (FT3). RESULTS: Serum SHBG levels decreased in inactive subjects but remained unchanged in the RVE group (p<0.001). Serum T concentrations increased during the first 3 weeks of bed-rest in both groups (p<0.0001), while E2 levels sharply rose with re-mobilization (p<0.0001). Serum PRL decreased in the control group but increased in the RVE group (p=0.021). C levels did not change over time (p≥0.10). TSH increased whilst FT3 decreased during bed-rest (p all ≤0.0013). CONCLUSIONS: Prolonged bed-rest has significant effects on parameters of endocrine and metabolic function, some of which are related to, or counteracted by physical activity.