Charge induced-defects in Poly (P-Phenylene Vinylene) (PPV)

We use a molecular dynamics method with semi-empirical quantum chemistry at the complete neglect of differential overlap (CNDO) level to study the charge-induced structural relaxation of poly(p-phenylene vinylene) (PPV) backbone, as a result of charge injection in light emitting diodes. Our results suggest that structural relaxation of PPV is accompanied by a local change in the electronic structure of the polymer leading to commonly known defects. The mobility of these defects along the polymer chains of different finite length was estimated from computer experiments. The charge rearrangement among the PPV atoms is also discussed

Peritonite por Rhizobium radiobacter

Rhizobium radiobacter (Agrobacterium radiobacter) is an aerobic Gram-negative rod belonging to Agrobacterium genus, a group of phytopathogenic bacteria present in the soil that has been implicated in human opportunistic infections. We report a clinical case of bacterial peritonitis in a 5-year-old child with chronic renal disease in peritoneal dialysis, who had a history of direct soil contact identified. The infection was treated with ceftazidime and piperaciline+tazobactam without relapses or the need to remove the peritoneal dialysis catheter

Systemic corticosteroid hypersensitivity in children

We describe 5 cases of immediate-type reactions to systemic corticosteroids observed during the last 2 decades in boys aged 2, 4, 8, 9, and 10 years. Symptoms ranged from generalized urticaria and angioedema to anaphylactic shock immediately after administration. Oral betamethasone was implicated in 2 cases, oral prednisolone in 2 cases, and intravenous prednisolone in 1 case. The parents of patient 5 refused the skin tests. The remaining patients underwent skin prick tests with the following undiluted corticosteroids: parenteral prednisolone, oral prednisolone, parenteral methylprednisolone, parenteral dexamethasone, parenteral hydrocortisone, and oral betamethasone. If the results were negative, intradermal tests were performed with the same drugs at increasing concentrations. Skin test results were positive for all suspect corticosteroids, thus indicating an immunoglobulin E-mediated mechanism. Two patients had positive skin test results to other corticosteroids, suggesting cross-reactivity. An oral challenge test was performed with deflazacort in 4 cases and with betamethasone in 1 case; the results were negative

Change mobility in conjugated polymer molecules

The use of conjugated polymers as active media in organic semiconductor devices demands a deep knowledge of the electronic processes involved at molecular level. Here we report the results obtained from self-consistent molecular dynamics calculations at the complete neglect of differential overlap level concerning intra-chain charge mobility for two well known polymers: polydiacetylene and poly(p-phenylene vinylene)

Quality of life in female users of antiageing cosmetic products/aesthetic treatments

Ageing is accompanied by physical changes, both at the physiological and appearance levels. The way people perceive these changes have important consequences on general health and quality of life (QoL). This study analysed the relationship between sociodemographic variables, psychological variables, use of antiageing cosmetic products/aesthetic treatments, and QoL.Le vieillissement s'accompagne de changements physiques, tant au niveau physiologique qu’au niveau de l'apparence. La façon dont les gens perçoivent ces changements a des conséquences importantes sur la santé générale et la qualité de vie (QdV). Cette étude a analysé la relation entre les variables sociodémographiques, les variables psychologiques, l'utilisation de produits cosmétiques anti-âge/soins esthétiques et la QdV. Méthodes: Cette étude transversale a inclus un échantillon de 271 femmes, âgées de 25 à 70 ans, utilisatrices de produits cosmétiques anti-âge et/ou de soins esthétiques. Les participants ont été évalués sur la morbidité psychologique (Hospit Anxiety and Depression Scale), les schémas d'apparence (Appearance Schemas Inventory - Revised), l'estime de soi (Roenberg Self-Esteem Scale), le perfectionnisme (Frost Multidimensional Perfectionism Scale), l'auto-perception du vieillissement (Brief Questionnaire sur les perceptions du vieillissement) et QdV (SF-12v2). Résultats: Être plus âgé et avoir un revenu du ménage plus élevé était associé à une meilleure qualité de vie. L'utilisation de produits raffermissants pour le visage, de produits de coloration capillaire et de soins solaires était également associée à une meilleure qualité de vie. La morbidité psychologique et le perfectionnisme ont contribué négativement à la qualité de vie, tandis que le revenu du ménage a contribué positivement. Les perceptions du vieillissement ont modéré la relation entre l'estime de soi et la qualité de vie. Conclusion: Selon les résultats, des programmes d'intervention visant à réduire la morbidité psychologique, à augmenter l'estime de soi, à promouvoir des schémas de perfectionnisme plus adaptatifs et à reconnaître le rôle de la perception de l'âge sont nécessaires pour améliorer la qualité de vie des femmes. L'influence de l'utilisation de produits cosmétiques pour prévenir/minimiser les signes du vieillissement doit être davantage perçue.This study was conducted at the Psychology Research Centre (PSI/01662), School of Psychology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (Ref.: UIDB/PSI/01662/2020

Usage patterns and self-esteem of female consumers of antiaging cosmetic products

The data presented in this study are available on request from the corresponding authors.Aging is an irreversible process of the human body, resulting from a progressive decrease in the biological functions of the organs, including the skin. This study analyzed the relationship between usage patterns of different types of anti-aging cosmetic products, sociodemographic variables, appearance schemes, psychological morbidity, perfectionism, and aging perception of aging with self-esteem. This cross-sectional study included a sample of 260 women, aged between 25 and 64 years, who are users of anti-aging cosmetics and/or aesthetic treatments. Participants were assessed on psychological morbidity (Hospital Anxiety and Depression Scale), appearance schemes (Appearance Schemas Inventory—Revised), perfectionism (Frost Multidimensional Perfectionism Scale), aging perceptions (Brief Aging Perceptions Questionnaire), and self-esteem (Rosenberg Self-Esteem Scale). The use of facial-firming cosmetics positively correlated with self-esteem. The results of regression analysis revealed that psychological morbidity and perfectionism contribute negatively to self-esteem, while marital status, professional status, and aging perceptions (positive consequences) contribute positively. According to the results, intervention programs to promote women’s self-esteem should focus on the reduction in psychological morbidity and the promotion of adaptive patterns of perfectionism and address aging perceptions. Longitudinal studies might help explain the complex relationship between the use of anti-aging cosmetic products and psychological variables, particularly self-esteem in women.This study was conducted at the Psychology Research Centre (PSI/01662), School of Psy chology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (Ref.: UIDB/01662/2020). This work was also supported by national funds from the European Regional Development Fund (ERDF) through the Northern Re gional Operational Programme (NORTE2020) under the project 47239-Cork2Cosmetic (NORTE-01- 0247-FEDER-047239). S.M. acknowledges the research fellowship (NORTE-01-0247-FEDER-047239), fully supported by national funding by Project 47239-Cork2Cosmetic (NORTE-01-0247-FEDER-047239)

Atomistic and mesoscopic modelling of electric charge evolution in polymers

We address some of the issues relating to charge transport in polymer based devices. We examine the effects of variable chain length on both intramolecular and intermolecular bipolar charge transport in polydiacetylene (PDA) and poly(para-phenylenevinylene) (PPV), which should apply more widely to other polymer systems. Self-consistent quantum molecular dynamics calculations have been used to provide information on charge transport properties of individual polymer strands. Generalised Monte-Carlo calculations, with specific description of the ensemble of polymer strands, have been used to assess the effects of texture on the competition between charge transport, trapping and recombination across the polymer slab. Our results show an unanticipated but important effect from relatively long-lived yet transient trapping

Dynamics of river plumes in the South Brazilian Bight and South Brazil

Research articleThe plumes from the rivers of the South Brazilian Bight (SBB) and South Brazil (SB) were studied using a realistic model configuration. River plume variability on continental shelves is driven by the input of river runoff into the shelf, by wind variability, and also by ambient currents and its seasonal variability, especially the Brazil Current, which are realistically modelled in this study. It is presented a simulation of 4 years using a nested configuration, which allows resolving the region around Florianópolis with very high resolution (∼150 m). The dispersion of river plumes was assessed not only with the hydrodynamical model results but also by using passive tracers whose dynamics was analyzed seasonally. Several dyes were released together with the river discharges. This approach allowed calculating the depths of the riverine freshwater, and the resulting regions affected by the plumes. Northward intrusions of waters from the southern region, under the potential influence of the distant La Plata river plume, were evaluated with a Lagrangian approach. The local river plumes are confined to the inner shelf, except south of 30°S where discharges from Lagoa dos Patos disperse over the shelf in the spring and summer. The Brazil Current flowing southward over the slope prevents the river plumes from interaction with oceanic mesoscale dynamics. The river plumes are, thus, mainly controlled by the wind forcing. The plumes from SBB are able to disperse until SB following the southward wind regime typical of the summer. And both the SB and La Plata river plumes are also able to reach SBB, forced by the northward wind typical of the winter season, until the latitude of 25.5°S. A low salinity belt (below 35) is present along the coastal region of SB and SBB year-round, supported by contributions from both the large and small rivers. The interaction between the different plumes influences the dispersion patterns, shielding the Florianṕolis coastal region from plumes of distant rivers, and dispersing the plume of SBB rivers away from Santa Catarina Island as it disperses southward during the summer months.Versión del edito

Retos en la Identificación de los Alumnos Superdotados: Cuestiones relacionadas con la Evaluación Psicológica.

This paper discusses issues related to the assessment of children and youth for the identification of giftedness, and presents specific rec-ommendations for educational measures in order to attend to the particular characteristics and needs of these students. We outline the most common difficulties related to the psychological assessment of these children, in-cluding the lack of adequate instruments for the assessment of the multiple dimensions of giftedness, as well as the shortage of training for this identi-fication. Regarding these difficulties, we describe some assessment procedures that assure higher levels of objectivity and validity in data, reducing the possibil-ity of false positives and false negatives in the identification of these stu-dents. In addition to psychological tests, we present the advantages of us-ing multiple informants and the contribution of different professionals and parents for this assessment. On the other hand, as we present giftedness as a result of a developmental process, it is important to conduct students’ as-sessment in phases, including an initial screening phase, followed by the sound assessment of students and nurturing. Finally, we present some sug-gestions for the advancement in giftedness identification and assessment, as a means to support the development of research in this area.Este artículo analiza los temas relacionados con la identificación de los estudiantes superdotados y recoge algunas recomendaciones específicas sobre medidas educativas, con el fin de responder a la diversidad de estos estudiantes. Se plantean las dificultades más comunes relacionadas con la evaluación psicológica de estos estudiantes, entre ellas la falta de instrumentos adecuados para la evaluación de las múltiples dimensiones de la superdotación y el talento, así como, la falta de formación que tienen los profesionales para esta identificación. Con respecto a estas dificultades, se describen algunos procedimientos de evaluación con el fin de asegurar mayores niveles de objetividad y validez de los datos, lo que reduce la posibilidad de falsos positivos y falsos negativos en la identificación de estos estudiantes. Además de las pruebas psicológicas, se presentan las ventajas del uso de diferentes fuentes de información y la contribución de los distintos profesionales y padres para esta evaluación. Por otro lado, es importante llevar a cabo la evaluación de los estudiantes superdotados por fases, incluyendo una fase de evaluación inicial (screening), seguida de la fase de diagnóstico o identificación; y la fase final, orientada a atender a la diversidad de estos estudiantes. Por último, se presentan algunas sugerencias para el avance en la identificación y evaluación de la superdotación, como un medio para apoyar el desarrollo de la investigación en este área.This article has been produced with the financial support by Spanish Ministry of Science and Technology (EDU2014-53646-R)

Impacto da capacidade cognitiva e das atribuições causais no rendimento escolar na matemática

A capacidade cognitiva e a motivação académica têm sido frequentemente assumidas como as variáveis do aluno mais determinantes da sua aprendizagem e rendimento escolar. Neste estudo, operacionalizando a capacidade cognitiva através de uma bateria de testes de raciocínio e a motivação através de uma escala de atribuições causais, analisa-se o impacto de ambas as variáveis psicológicas no rendimento dos alunos na disciplina de Matemática. A amostra é formada por todos os alunos do 6.° ano de escolaridade de uma escola privada, com contrato de associação, do distrito de Braga. Os resultados mostram que a capacidade cognitiva se apresenta como o melhor preditor do rendimento escolar, havendo ainda parte da variância do rendimento na matemática associada, em sentido negativo, à atribuição causal do sucesso à sorte. Este dado sugere que alunos que não atribuem o seu rendimento ao acaso apresentam, em geral, melhores classificações escolares.The cognitive ability and academic motivation have often been assumed as the most determinant variables of student learning and their school performance. ln this study, the operationalization of the cognitive ability through a battery of tests of reasoning and motivation through a scale of causal attributions, alIow us analyze the impact of both psychological variables in the student performance in mathematics. The sample consists of all students in the 6th grade at a private school, integrated in public system, in the district of Braga. The results showed that cognitive ability remains on the best predictor of academic performance, and part of students ' mathematics results variance is related negatively to causal attribution of success to luck. This last aspect shows that students who do not attribute their academic performance to random reasons have, in general, better academic results