1,977 research outputs found

    Comparison of solar radio and EUV synoptic limb charts during the present solar maximum

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    The present solar cycle is particular in many aspects: it had a delayed rising phase, it is the weakest of the last 100 years, and it presents two peaks separated by more than one year. To understand the impact of these characteristics on the solar chromosphere and coronal dynamics, images from a wide wavelength range are needed. In this work we use the 17~GHz radio continuum, formed in the upper chromosphere and the EUV lines 304 and 171~{\AA}, that come from the transition region (He II) and the corona (Fe IX, X), respectively. We analyze daily images at 304 and 171~{\AA} obtained by the Atmospheric Imaging Assembly (AIA). The 17~GHz maps were obtained by the Nobeyama Radioheliograph (NoRH). To construct synoptic limb charts, we calculated the mean emission of delimited limb areas with 100" wide and angular separation of 5∘5^\circ. At the equatorial region, the results show an hemispheric asymmetry of the solar activity. The northern hemisphere dominance is coincident with the first sunspot number peak, whereas the second peak occurs concurrently with the increase in the activity at the south. The polar emission reflects the presence of coronal holes at both EUV wavelengths, moreover, the 17~GHz polar brightenings can be associated with the coronal holes. Until 2013, both EUV coronal holes and radio polar brightenings were more predominant at the south pole. Since then they have not been apparent in the north, but thus appear in the beginning of 2015 in the south as observed in the synoptic charts. This work strengthens the association between coronal holes and the 17~GHz polar brightenings as it is evident in the synoptic limb charts, in agreement with previous case study papers. The enhancement of the radio brightness in coronal holes is explained by the presence of bright patches closely associated with the presence of intense unipolar magnetic fields.Comment: 6 pages, 5 figures. Acccepted for publication in Astronomy & Astrophysic

    Portuguese validation of the Cognitive Emotion Regulation Questionnaire short version in youth: Validity, reliability and invariance across gender and age

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    The Cognitive Emotion Regulation Questionnaire (CERQ) is a multidimensional measure widely used to access nine cognitive emotion regulation strategies. In this study, we examined the psychometric properties of the CERQ-Short Portuguese version. A sample of 1052 adolescents (aged 10-25 years old, 60.53% females) completed the CERQ-Short form, the Positive and Negative Affect Schedule, the Generalised Anxiety Disorder Scale, and the Patient Health Questionnaire. Confirmatory factor analyses showed that the nine latent dimensions of CERQ-Short provided an acceptable fit to the data. Measurement invariance (for gender and three age groups), reliability, and construct validity were adequate. The adaptative strategies were positively associated with higher positive affect, and maladaptive strategies with higher negative affect, symptoms of generalized anxiety, and depression. These results suggest that CERQ-Short is a valid and reliable measure for Portuguese-speaking samples. Moreover, CERQ-Short’s length makes it a cost-effective tool for both clinicians and researchers.info:eu-repo/semantics/acceptedVersio

    Ensaios de integridade estrutural de placas angulares de fixação de fracturas ósseas do fémur

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    Neste trabalho descreve-se o projecto de um dispositivo mecùnico desenvolvido para a realização de ensaios segundo a norma ASTM F384-00 (2000) de placas de osteossíntese anguladas. O dispositivo foi objecto de uma anålise estrutural usando o método dos elementos finitos. Algumas placas foram ensaiadas estaticamente e suas características mecùnicas, de acordo com a norma, determinadas

    Sodium dodecyl sulfate allows the persistence and recovery of biofilms of Pseudomonas fluorescens formed under different hydrodynamic conditions

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    The effect of the anionic surfactant sodium dodecyl sulfate (SDS) on Pseudomonas fluorescens biofilms was investigated using flow cell reactors with stainless steel substrata, under turbulent (Re=5200) and laminar (Re=2000) flow. Steady-state biofilms were exposed to SDS in single doses (0.5, 1, 3 and 7 mM) and biofilm respiratory activity and mass measured at 0, 3, 7 and 12 h after the SDS application. The effect of SDS on biofilm mechanical stability was assessed using a rotating bioreactor. Whilst high concentrations (7 mM) of SDS promoted significant biofilm inactivation, it did not significantly reduce biofouling. Turbulent and laminar flow-generated biofilms had comparable susceptibility to SDS application. Following SDS exposure, biofilms rapidly recovered over the following 12 h, achieving higher respiratory activity values than before treatment. This phenomenon of posttreatment recovery was more pronounced for turbulent flow-generated biofilms, with an increase in SDS concentration. The mechanical stability of the biofilms increased with surfactant application, except for SDS concentrations near the critical micellar concentration, as measured by biofilm removal due to an increase in external shear stress forces. The data suggest that although SDS exerts antimicrobial action against P. fluorescens biofilms, even if only partial and reversible, it had only limited antifouling efficacy, increasing biofilm mechanical stability at low concentrations and allowing significant and rapid recovery of turbulent flow-generated biofilms.Fundação para a CiĂȘncia e a Tecnologia (FCT

    Spatial accessibility and social inclusion: The impact of Portugal's last health reform

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    Health policies seek to promote access to health care and should provide appropriate geographical accessibility to each demographical functional group. The dispersal demand of health‐careservices and the provision for such services atfixed locations contribute to the growth of inequality intheir access. Therefore, the optimal distribution of health facilities over the space/area can lead toaccessibility improvements and to the mitigation of the social exclusion of the groups considered mostvulnerable. Requiring for such, the use of planning practices joined with accessibility measures. However,the capacities of Geographic Information Systems in determining and evaluating spatial accessibility inhealth system planning have not yet been fully exploited. This paper focuses on health‐care services planningbased on accessibility measures grounded on the network analysis. The case study hinges on mainlandPortugal. Different scenarios were developed to measure and compare impact on the population'saccessibility. It distinguishes itself from other studies of accessibility measures by integrating network data ina spatial accessibility measure: the enhanced two‐stepfloating catchment area. The convenient location forhealth‐care facilities can increase the accessibility standards of the population and consequently reducethe economic and social costs incurred. Recently, the Portuguese government implemented a reform thataimed to improve, namely, the access and equity in meeting with the most urgent patients. It envisaged,in terms of equity, the allocation of 89 emergency network points that ensured more than 90% of thepopulation be within 30 min from any one point in the network. Consequently, several emergency serviceswere closed, namely, in rural areas. This reform highlighted the need to improve the quality of the emergencycare, accessibility to each care facility, and equity in their access. Hence, accessibility measures becomean efficient decision‐making tool, despite its absence in effective practice planning. According to anapplication of this type of measure, it was possible to verify which levels of accessibility were decreased,including the most disadvantaged people, with a larger time of dislocation of 12 min between 2001 and 2011

    Contextual determinants of HR professionals’ self-perceptions of unethical HRM practices

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    This study examined human resources (HR) professionals’ self-perceptions of ethically questionable human resource management (HRM) practices (i.e., a disregard for the individual, favoring those in power, and discrimination). The research sought specifically to determine how these perceptions are influenced by their organizations’ ethical infrastructure and corporate social responsibility (CSR) practices. Data were collected from 134 HR professionals using an anonymous structured questionnaire. The scope of organizations’ ethics programs and the degree of importance given to developing an ethical infrastructure were found to predict the level of acceptance of unethical HRM practices related to discrimination. These practices are also less acceptable to professionals from organizations that are perceived as more socially responsible regarding their employees. Additional studies with larger samples are needed to determine more clearly not only the influence of contextual determinants but also the practical consequences of high levels of acceptance of unethical practices in HRM. Organizations can decrease their HR professionals’ acceptance of ethically questionable HRM practices by developing and emphasizing a strong ethical infrastructure and CSR practices, especially those affecting employees. HR professionals’ perceptions of ethical issues have rarely been analyzed using empirically tested methods. By surveying HR professionals, this study contributes to a fuller understanding of their perceptions regarding the ethics of their own practices. The results show that contextual determinants play an important role in predicting the level of acceptance of unethical HRM practices, especially those leading to discrimination.info:eu-repo/semantics/publishedVersio

    Using a glass-fibre reinforced polymer composite in the production of sustainable water storage vessels

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    The quest for sustainability by rethinking materials, products and production strategies is an enormous challenge currently laid upon the economic sector. Materials selection plays a critical role in this challenge. The present work describes a technological, environmental and economic study of the production of a water storage glass-fibre reinforced composite vessel. The vessel was evaluated via a Life Cycle Assessment/Life Cycle Costing (LCA/LCC) integrated model. The most significant life cycle phase was found to be the raw materials production, in which the Fossil fuels, Respiratory inorganics and Climate change were the relevant impact categories. The vessel environmental and economic performances could be improved if an end of life (EoL) option different from landfill had been chosen. The present work describes a new integrated way of analysing the environmental and economic performances of a structural product full life cycle. It also highlights the role and importance of fibre reinforced polymer composites in the quest for sustainable products.FCT projeto SFRH/BD/60852/2009 e IPC projeto UID/CTM/50025/201
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