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Over the centuries there has been a growing trend of societies and it is possible to verify their economic growth. This growth has provided an increased pressure on natural resources, often over-reaching the boundaries of each country, which has called into question the level of environmental sustainability in different countries. Sustainability is understood as a complex concept involving ecological, social, economic dimensions and temporal urban processes. Therefore, Firmino (2009) suggests that the ecological footprint (EF) allows people to establish dependency relations between human activities and the natural resources required for such activities and for the absorption of waste generated. According to Bergh & Verbruggen (1999) the EF is an objective, impartial and one-dimensional indicator that enables people to assess the sustainability. The Superior Schools have a crucial role in building the vision of a sustainable future as a reality, because in transmitting values and environmental principles to his students, are providing that they, in exercising his professional activity, make decisions weighing the environmental values. This ensures improved quality of life. The present study aims to determine the level of environmental sustainability of the Academic Community of Lisbon College of Health Technology (ESTeSL), by calculating the EF, and describe whether a relation between Footprint and various socio-demographic characteristics of the subjects.

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Chromia (Cr2O3) has been extensively explored for the purpose of developing widespread industrial applications, owing to the convergence of a variety of mechanical, physical and chemical properties in one single oxide material. Various methods have been used for large area synthesis of Cr2O3 films. However, for selective area growth and growth on thermally sensitive materials, laser-assisted chemical vapour deposition (LCVD) can be applied advantageously. Here we report on the growth of single layers of pure Cr2O3 onto sapphire substrates at room temperature by low pressure photolytic LCVD, using UV laser radiation and Cr(CO)(6) as chromium precursor. The feasibility of the LCVD technique to access selective area deposition of chromia thin films is demonstrated. Best results were obtained for a laser fluence of 120 mJ cm(-2) and a partial pressure ratio of O-2 to Cr(CO)(6) of 1.0. Samples grown with these experimental parameters are polycrystalline and their microstructure is characterised by a high density of particles whose size follows a lognormal distribution. Deposition rates of 0.1 nm s(-1) and mean particle sizes of 1.85 mu m were measured for these films. (C) 2011 Elsevier B.V. All rights reserved.

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Síndrome de Waardenburg - Perda de audição: neurossensorial, uni ou bilateral; possibilidade de existir micrótia ou apêndices pré-auriculares; nariz achatado – alargamento da pirâmide nasal; alterações na pigmentação de pele, cabelo e olhos.

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The scaling exponent of 1.6 between anomalous Hall and longitudinal conductivity, characteristic of the universal Hall mechanism in dirty-metal ferromagnets, emerges from a series of CrO2 films as we systematically increase structural disorder. Magnetic disorder in CrO2 increases with temperature and this drives a separate topological Hall mechanism. We find that these terms are controlled discretely by structural and magnetic defect populations, and their coexistence leads to apparent divergence from exponent 1.6, suggesting that the universal term is more prevalent than previously realized.

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Este artigo compara o Sistema de Normalização Contabilística (SNC) e o Plano Oficial de Contabilidade (POC), no que respeita ao reconhecimento, mensuração e divulgação dos activos fixos tangíveis. Para o efeito, analisou-se os dois normativos e procedeu-se à elaboração de quadros comparativos. Verificou-se que, de um modo geral, o SNC não se afasta muito do POC, pelo facto deste último nos últimos anos, ter sofrido várias influências anglo-saxónicas, e o SNC baseia-se nas normas internacionais de contabilidade adaptadas pela União Europeia. No entanto, trata-se de um sistema mais complexo do que o POC, contemplando numa só norma, todas as disposições gerais relativamente a esta matéria e remetendo para outras normas o tratamento de situações específicas.

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O Traumatismo Cranioencefálico constitui a principal causa de morte e sequelas em pacientes politraumatizados, convertendo se, nos últimos anos, num importante problema de saúde pública. Smeltzer e Bare (2006), conceituam Traumatismo Craniano/Traumatismo Cranioencefálico (TCE) como uma lesão do crânio ou do cérebro que é suficientemente grave para interferir no seu funcionamento normal. Cerca de 4 a 30% dos ferimentos na cabeça envolvem a base do crânio sendo que há atingimento do osso temporal em 18 a 40%. Dependendo do tipo e da gravidade do traumatismo, podem ocorrer alterações estruturais e funcionais no sistema audiovestibular.

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Os bebés reagem aos sons externos ainda dentro da barriga da mãe e já são capazes de discriminar diferentes sons da fala e reconhecer a voz materna. Os bebés aprendem os sons específicos da língua a que estão expostos durante os primeiros 6 meses de vida. O diagnóstico audiológico no primeiro ano de vida é importante para um prognóstico favorável ao desenvolvimento da criança, oferecendo uma intervenção ainda no período crítico de manutenção e plasticidade funcional do sistema nervoso central.

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The deposition of highly oriented a-axis CrO(2) films onto Al(2)O(3)(0001) by atmospheric pressure (AP)CVD at temperatures as low as 330 C is reported. Deposition rates strongly depend on the substrate temperature, whereas for film surface microstructures the dependence is mainly on film thickness. For the experimental conditions used in this work, CrO(2) growth kinetics are dominated by a surface reaction mechanism with an apparent activation energy of (121.0 +/- 4.3) kJ mol(-1). The magnitude and temperature dependence of the saturation magnetization, up to room temperature, is consistent with bulk measurements.

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This work reports on the synthesis of CrO2 thin films by atmospheric pressure CVD using chromium trioxide (CrO3) and oxygen. Highly oriented (100) CrO2 films containing highly oriented (0001) Cr2O3 were grown onto Al2O3(0001) substrates. Films display a sharp magnetic transition at 375 K and a saturation magnetization of 1.92 mu(B)/f.u., close to the bulk value of 2 mu(B)/f.u. for the CrO2.

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In this work we report on the structure and magnetic and electrical transport properties of CrO2 films deposited onto (0001) sapphire by atmospheric pressure (AP)CVD from a CrO3 precursor. Films are grown within a broad range of deposition temperatures, from 320 to 410 degrees C, and oxygen carrier gas flow rates of 50-500 seem, showing that it is viable to grow highly oriented a-axis CrO2 films at temperatures as low as 330 degrees C i.e., 60-70 degrees C lower than is reported in published data for the same chemical system. Depending on the experimental conditions, growth kinetic regimes dominated either by surface reaction or by mass-transport mechanisms are identified. The growth of a Cr2O3 interfacial layer as an intrinsic feature of the deposition process is studied and discussed. Films synthesized at 330 degrees C keep the same high quality magnetic and transport properties as those deposited at higher temperatures.

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Chromium oxides, CrxOy, are of great interest due to the wide variety of their technological applications. Among them, CrO2 has been extensively investigated in recent years because it is an attractive compound for use in spintronic heterostructures. However, its synthesis at low temperatures has been a difficult task due to the metastable nature of this oxide. This is indeed essential to ensure interface quality and the ability to coat thermal-sensitive materials such as those envisaged in spintronic devices. Pulsed Laser Deposition (PLD) is a technique that has the potential to meet the requirements stated above. In this work, we describe our efforts to grow chromium oxide thin films by PLD from Cr8O21 targets, using a KrF excimer laser. The as-deposited films were investigated by X-ray diffraction and Rutherford backscattering spectrometry. Structural and chemical composition studies showed that the films consist of a mixture of amorphous chromium oxides exhibiting different stoichiometries depending on the processing parameters, where nanocrystals of mainly Cr2O3 are dispersed. The analyses do not exclude the possibility of co-deposition of Cr2O3 and a low fraction of CrO2.

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Here, we use Andreev reflection spectroscopy to study the spin polarization of high quality CrO2 films. We study the spin polarization as a function of growth temperature, resulting in grain size and electrical resistivity. In these films low temperature growth appears to be a necessary but not sufficient condition to guarantee the observation of high spin polarization, and this is only observed in conjunction with suppressed superconducting gap values and anomalously low interface properties. We suggest that this combination of observations is a manifestation of the long range spin triplet proximity effect. (C) 2007 American Institute of Physics.

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Neste trabalho, discutimos e analisamos as Demonstrações Financeiras (DF) elaboradas de acordo com a proposta do Sistema de Normalização Contabilística (SNC), apresentada pela Comissão de Normalização Contabilística (CNC), comparativamente com as DF preparadas de acordo com o Plano Oficial de Contabilidade (POC), em vigor em Portugal por imposição do Decreto-Lei n.º 410/89, de 21 de Novembro. Assim, marcamos separadamente os aspectos normativos que norteiam a execução dessas DF com referências comparativas entre elas, não com intuito de subjugar umas em detrimento de outras, mas de mostrar as suas diferenças em relação à essência, forma e finalidade. In this work, we discuss and analyze the Financial Reports (FR) made in accordance with the essay of Sistema de Normalização Contabilística (SNC) and presented by Comissão de Normalização Contabilística (CNC). In addition, we made a comparison with the FR prepared following the Plano Oficial de Contabilidade (POC) that is in use in Portugal by legal origin (Decreto-Lei n.º 410/89, de 21 de Novembro). Therefore, we emphasize the normative issues that drive FR construction with systematic comparisons between both. We do not aim to determine which one is the best normative, but to examine their differences related with essence, methods and goals.

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This work reports on the synthesis of chromium oxide thin films prepared by photodissociation of Cr(CO)(6) in an oxidizing atmosphere, using a pulsed UV laser (KrF, lambda = 248 nm). The experimental conditions, which should enable the synthesis of CrO2, are discussed and results on the deposition of CrxOy films on Al2O3 (0001) substrates are presented.

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This work reports on the synthesis of chromium (III, IV) oxides films by KrF laser-assisted CVD. Films were deposited onto sapphire substrates at room temperature by the photodissociation of Cr(CO)(6) in dynamic atmospheres containing oxygen and argon. A study of the processing parameters has shown that partial pressure ratio Of O-2 to Cr(CO)(6) and laser fluence are the prominent parameters that have to be accurately controlled in order to co-deposit both the crystalline oxide phases. Films consistent with such a two-phase system were synthesised for a laser fluence of 75 mJ cm(-2) and a partial pressure ratio of about 1. (c) 2005 Elsevier B.V. All rights reserved.