Implementação de WDM com dispositivos semicondutores

Este trabalho utiliza uma estrutura pin empilhada, baseada numa liga de siliceto de carbono amorfo hidrogenado (a-Si:H e/ou a-SiC:H), que funciona como filtro óptico na zona visível do espectro electromagnético. Pretende-se utilizar este dispositivo para realizar a demultiplexagem de sinais ópticos e desenvolver um algoritmo que permita fazer o reconhecimento autónomo do sinal transmitido em cada canal. O objectivo desta tese visa implementar um algoritmo que permita o reconhecimento autónomo da informação transmitida por cada canal através da leitura da fotocorrente fornecida pelo dispositivo. O tema deste trabalho resulta das conclusões de trabalhos anteriores, em que este dispositivo e outros de configuração idêntica foram analisados, de forma a explorar a sua utilização na implementação da tecnologia WDM. Neste trabalho foram utilizados três canais de transmissão (Azul – 470 nm, Verde – 525 nm e Vermelho – 626 nm) e vários tipos de radiação de fundo. Foram realizadas medidas da resposta espectral e da resposta temporal da fotocorrente do dispositivo, em diferentes condições experimentais. Variou-se o comprimento de onda do canal e o comprimento de onda do fundo aplicado, mantendo-se constante a intensidade do canal e a frequência de transmissão. Os resultados obtidos permitiram aferir sobre a influência da presença da radiação de fundo e da tensão aplicada ao dispositivo, usando diferentes sequências de dados transmitidos nos vários canais. Verificou-se, que sob polarização inversa, a radiação de fundo vermelho amplifica os valores de fotocorrente do canal azul e a radiação de fundo azul amplifica o canal vermelho e verde. Para polarização directa, apenas a radiação de fundo azul amplifica os valores de fotocorrente do canal vermelho. Enquanto para ambas as polarizações, a radiação de fundo verde, não tem uma grande influência nos restantes canais. Foram implementados dois algoritmos para proceder ao reconhecimento da informação de cada canal. Na primeira abordagem usou-se a informação contida nas medidas de fotocorrente geradas pelo dispositivo sob polarização inversa e directa. Pela comparação das duas medidas desenvolveu-se e testou-se um algoritmo que permite o reconhecimento dos canais individuais. Numa segunda abordagem procedeu-se ao reconhecimento da informação de cada canal mas com aplicação de radiação de fundo, tendo-se usado a informação contida nas medidas de fotocorrente geradas pelo dispositivo sob polarização inversa sem aplicação de radiação de fundo com a informação contida nas medidas de fotocorrente geradas pelo dispositivo sob polarização inversa com aplicação de radiação de fundo. Pela comparação destas duas medidas desenvolveu-se e testou-se o segundo algoritmo que permite o reconhecimento dos canais individuais com base na aplicação de radiação de fundo.

Housework, paid work and psychiatric symptoms

OBJECTIVE: To evaluate the hypothesis that work burden, the simultaneous engagement in paid work and unpaid family housework, is a potential risk factor for psychiatric symptoms among women. METHODS: A cross-sectional study was carried out with 460 women randomly selected from a poor area of the city of Salvador, Brazil. Women between 18 to 70 years old, who reported having a paid occupation or were involved in unpaid domestic activities for their families, were eligible. Work burden-related variables were defined as: a) double work shift, i.e., simultaneous engagement in a paid job plus unpaid housework; and b) daily working time. Psychiatric symptoms were collected through a validated questionnaire, the QMPA. RESULTS: Positive, statistically significant associations between high (>7 symptoms) QMPA scores and either double work shift (prevalence ratio -- PR=2.04, 95% confidence interval -- CI: 1.16, 2.29) or more than 10 hours of daily work time (PR=2.29, 95% CI: 1.96, 3.43) were found after adjustment for age, marital status and number of pre-school children. CONCLUSIONS: Major correlates of high QMPA scores are work burden variables. Being married or having pre-school children are also associated with high QMPA scores only when associated with work burden.

Evaluation of the improvements on pharmacy technicians' work practices after implementation of operational procedures

Several antineoplasic drugs have been demonstrated to be carcinogenic or to have mutagenic and teratogenic effects. The greatest protection is achieved with the implementation of administrative and engineering controls and safety procedures. Objective: to evaluate the improvements on pharmacy technicians' work practices, after the implementation of operational procedures related to individual protection, biologic safety cabinet disinfection and cytotoxic drug preparation. Method: case-study in a hospital pharmacy undergoing a certification process. Six pharmacy technicians were observed during their daily activities. Characterization of the work practices was made using a checklist based on ISOPP and PIC guidelines. The variables studied concerning cleaning/disinfection procedures, personal protective equipment and procedures for preparing cytotoxic drugs. The same work practices were evaluated after four months of operational procedures implementation. Concordance between work practices and guidelines was considered to be a quality indicator (guidelines concordance practices number/total number of practices x 100). Results: improvements were observed after operational procedures implementation. An improvement of 6,25% in personal protective equipment practice was achieved by changing second pair of gloves every thirty minutes. The major progress, 10%, was obtained in disinfection procedure, where 80% of tasks are now realized according to guidelines.By now, we hot an improvement of only 1% at drug preparation procedure by placing one cytotoxic drug at a time inside the biological safety cabinet. Then, 85% of practices are according to guidelines. Conclusion: before operational procedures implementation 80,3% of practices were according to the guidelines, while now is 84,4%. This indicates that is necessary to review the procedures frequently in the benefit to reduce the risks associated with handling cytotoxic drugs and maintenance of drug specifications.

Mantle source heterogeneity, magma generation and magmatic evolution at Terceira Island (Azoresarchipelago): Constraints from elemental and isotopic (Sr, Nd, Hf, and Pb) data

This work addresses the present-day (<100 ka) mantle heterogeneity in the Azores region through the study of two active volcanic systems from Terceira Island. Our study shows that mantle heterogeneities are detectable even when "coeval" volcanic systems (Santa Barbara and Fissural) erupted less than 10 km away. These volcanic systems, respectively, reflect the influence of the Terceira and D. Joao de Castro Bank end-members defined by Beier et at (2008) for the Terceira Rift Santa Barbara magmas are interpreted to be the result of mixing between a HIMU-type component, carried to the upper mantle by the Azores plume, and the regional depleted MORB magmas/source. Fissural lavas are characterized by higher Ba/Nb and Nb/U ratios and less radiogenic Pb-206/Pb-204, Nd-143/Nd-144 and Hf-176/Hf-177, requiring the small contribution of delaminated sub-continental lithospheric mantle residing in the upper mantle. Published noble gas data on lavas from both volcanic systems also indicate the presence of a relatively undegassed component, which is interpreted as inherited from a lower mantle reservoir sampled by the ascending Azores plume. As inferred from trace and major elements, melting began in the garnet stability field, while magma extraction occurred within the spinel zone. The intra-volcanic system's chemical heterogeneity is mainly explained by variable proportions of the above-mentioned local end-members and by crystal fractionation processes. (C) 2011 Elsevier By. All rights reserved.

Working hours, work-life conflict and health in precarious and "permanent" employment

OBJECTIVE: The expansion of precarious employment in OECD countries has been widely associated with negative health and safety effects. Although many shiftworkers are precariously employed, shiftwork research has concentrated on full-time workers in continuing employment. This paper examines the impact of precarious employment on working hours, work-life conflict and health by comparing casual employees to full-time, "permanent" employees working in the same occupations and workplaces. METHODS: Thirty-nine convergent interviews were conducted in two five-star hotels. The participants included 26 full-time and 13 casual (temporary) employees. They ranged in age from 19 to 61 years and included 17 females and 22 males. Working hours ranged from zero to 73 hours per week. RESULTS: Marked differences emerged between the reports of casual and full-time employees about working hours, work-life conflict and health. Casuals were more likely to work highly irregular hours over which they had little control. Their daily and weekly working hours ranged from very long to very short according to organisational requirements. Long working hours, combined with low predictability and control, produced greater disruption to family and social lives and poorer work-life balance for casuals. Uncoordinated hours across multiple jobs exacerbated these problems in some cases. Health-related issues reported to arise from work-life conflict included sleep disturbance, fatigue and disrupted exercise and dietary regimes. CONCLUSIONS:This study identified significant disadvantages of casual employment. In the same hotels, and doing largely the same jobs, casual employees had less desirable and predictable work schedules, greater work-life conflict and more associated health complaints than "permanent" workers.

The impact of night work on subjective reports of well-being: an exploratory study of health care workers from five nations

OBJECTIVE: To carry out a survey data collection from health care workers in Brazil, Croatia, Poland, Ukraine and the USA with two primary goals: (1) to provide information about which aspects of well-being are most likely to need attention when shiftwork management solutions are being developed, and (2) to explore whether nations are likely to differ with respect to the impacts of night work on the well-being of workers involved in health care work. METHODS: The respondents from each nation were sorted into night worker and non-night worker groups. Worker perceptions of being physically tired, mentally tired, and tense at the end of the workday were examined. Subjective reports of perceived felt age were also studied. For each of these four dependent variables, an ANCOVA analysis was carried out. Hours worked per week, stability of weekly work schedule, and chronological age were the covariates for these analyses. RESULTS: The results clearly support the general proposal that nations differ significantly in worker perceptions of well-being. In addition, perceptions of physical and mental tiredness at the end of the workday were higher for night workers. For the perception of being physically tired at the end of a workday, the manner and degree to which the night shift impacts the workers varies by nation. CONCLUSIONS: Additional research is needed to determine if the nation and work schedule differences observed are related to differences in job tasks, work schedule structure, off-the-job variables, and/or other worker demographic variables.

Job control, job demands, social support at work and health among adolescent workers

OBJECTIVE: To evaluate physical and psychological dimensions of adolescent labor (such as job demands, job control, and social support in the work environment), and their relation to reported body pain, work injuries, sleep duration and daily working hours. METHODS: A total of 354 adolescents attending evening classes at a public school in São Paulo, Brazil, answered questionnaires regarding their living and working conditions (Karasek's Job Content Questionnaire, 1998), and their health status. Data collection took place in April and May 2001. Multiple logistic regression analysis was used to determine relations among variables. RESULTS: Psychological job demands were related to body pain (OR=3.3), higher risk of work injuries (OR=3.0) and reduced sleep duration in weekdays (Monday to Thursday) (p<0.01). Lower decision authority in the workplace (p=0.03) and higher job security (p=0.02) were related to longer daily working hours. CONCLUSIONS: It was concluded that besides physical stressors, psychological factors are to be taken into account when studying adolescent working conditions, as they may be associated with negative job conditions and health effects.

Cooperation mechanism for team-work based multi-agent system in dynamic scheduling through meta-heuristics

This paper describes a Multi-agent Scheduling System that assumes the existence of several Machines Agents (which are decision-making entities) distributed inside the Manufacturing System that interact and cooperate with other agents in order to obtain optimal or near-optimal global performances. Agents have to manage their internal behaviors and their relationships with other agents via cooperative negotiation in accordance with business policies defined by the user manager. Some Multi Agent Systems (MAS) organizational aspects are considered. An original Cooperation Mechanism for a Team-work based Architecture is proposed to address dynamic scheduling using Meta-Heuristics.

Work in progress: representar o «outro» segundo o pensamento antropofágico casos de estudo - Hans Staden e Les Maîtres Fous

O presente artigo analisa o filme de Luis Alberto Pereira «Hans Staden» (1999), baseado no livro de Hans Staden «Duas Viagens ao Brasil» (1557), e o documentário/filme «Les Maîtres Fous» (1955) de Jean Rouch, tendo em consideração o pensamento antropofágico. Estas obras focalizam o choque cultural entre “civilizado” e “selvagem”, entre ritual canibal e ritual antropofágico, entre o «Nós» e os «Outros», encontros que permitem uma análise mais concreta à concepção de alteridade. A representação cinematográfica permite uma aproximação ao conceito antropofágico de apropriação da cultura externa, para posteriormente a reproduzir numa interpretação segundo a concepção ocidental do que figuram os rituais em questão. O Movimento Antropófago, pelo seu carácter vanguardista, concilia a matriz fundadora brasileira e ao mesmo tempo enaltece a irreverência de análise, e neste artigo serve de fundamento teórico e prático à decomposição dos exemplos. O pensamento antropófago e a sua aplicabilidade aos exemplos seleccionados permitem também aprofundar o estudo sobre o imaginário europeu enquanto recriação de relatos datados de viajantes ou colonizadores, pois a manutenção de um acervo estereotipado historicamente serve como forma de “legitimar” concepções. As duas obras focalizam a representação indígena e africana - o “selvagem” - na construção do imaginário ocidental - “civilizado” - dicotomia que nos permite desmistificar relações interculturais.

Health, sleep and lack of time: relations to domestic and paid work in nurses

OBJECTIVE: To assess whether reported morbidity and complaints of lack of time and sleep are associated with the burden of professional work and housework among nurses. METHODS: A cross-sectional exploratory study was carried out among female nurses and nurse assistants (N=206) of a public hospital in Rio de Janeiro, Brazil. Data were collected by means of a questionnaire. The prevalence ratio and 95% confidence intervals were estimated. RESULTS: Mean duration of professional work and housework time was 40.4 and 31.6 hours/week, respectively. Long professional working time (over 44 hours/week) were associated with mild emotional disorders (PR=1.37; 95% CI: 1.05-1.80), complaints of lack of time for resting/leisure (PR=1.61; 95% CI: 1.31-1.97), housework (PR=1.48; 95% CI: 1.12-1.97), and childcare (PR=1.99; 95% CI: 1.51-2.63). Long housework time (over 28 hours/week) was associated with lower prevalence of lack of time for childcare (PR=0.62; 95% CI: 0.46-0.84). High housework load was associated with lack of personal time and complaints of varicose veins (PR=1.31; 95% CI: 1.14-1.50 and PR=1.31; 95% CI: 1.08-1.58, respectively). Complaints of varicose veins were also frequent among female nurses with a total work load above 84 hours (PR=1.30; 95% CI: 1.05-1.61), though this group has shown a lower prevalence of arterial hypertension and recurrent headaches (PR=0.35; 95% CI: 0.15-0.83 and PR=0.53; 95% CI: 0.32-0.89, respectively). CONCLUSIONS: Results suggest that both professional and home environments are relevant in the evaluation of work overload on nurses' health and their family and social life. It is stressed the need for instruments for analyzing total workload among female populations.

Motivations in volunteer work

The objective of this paper is to review and discuss the literature about volunteers’ motivations to donate their time to NGOs (Non Governmental Organisations). According to Parboteeah, Cullenb & Lim (2004) management research has not paid much attention to voluntarism, however, voluntarism is a substantial part of productive work for many societies. Wilson & Pimm (1996) show that in Great Britain about 39% of the adult population has been involved in some volunteer activity for some period of time. In the U.S.A. these values reach 50% (Wilson & Pimm, 1996). Considering the benefits that voluntarism can bring to an organisation, we understand that more attention must be devoted to this phenomenon. The more an organisation knows volunteers, the better this organisation will be able to meet the needs and expectations of these individuals. We present a literature review that illustrates and compares the different motivations associated with volunteer work. The paper includes a bibliographical databases search in specialised journals. The search used the key words “motivations” and “voluntarism” (in the heading and text body) and covered all numbers between 2000 and 2007. We identify the existence of repeated motivations (Holmberg & Söderlung, 2005; Prouteau & Wolff, 2008; Soupourmas & Ironmonger, 2001; Yavas & Riecken, 1997), which allow the establishment of a typology of volunteers’ motivations, based on four categories: altruism, social needs, self-esteem, learning and self-development. Finally we identify three main gaps in the literature that justify further research. First, research focusing on the differences between motivations related to volunteers’ "Attraction" versus "Retention" in NGO’s is nil. Second, the great majority of the studies rely on north American (USA and Canada) and Australian context, which demands for further research in European countries. Third, the majority of NGOs researched are related to sport, art or the environment, and it would be interesting to explore the relationship between motivation and NGO type. These questions may obtain interesting answers for NGO management, in particular with regard to volunteer attraction and retention.

Motivations and management factors of volunteer work in nonprofit organisations: a literature review

The objective of this paper is to review and discuss the literature about volunteers’ motivations to donate their time to NPOs and the management factors that can influence volunteer work. Firstly, the paper illustrates and compares the different types of motivation followed by a presentation of a typology that organises the volunteers’ motivations into four types: (i) altruism, (ii) belonging, (iii) ego and social recognition and (iv) development and learning. Secondly we discuss the key management factors in volunteering: recruitment, training and rewarding. Finally, we present four gaps in the literature that justify the scope for further research: (i) omission of differences between motivations related to volunteers’ "Attraction" versus "Retention"; (ii) focus of the research on the USA, UK and Australia context; (iii) absence of comparative analyses that relate motivations by NPO types and (iv) comprehension of how management factors (recruitment, training and rewarding) influence volunteers’ satisfaction and retention.

Recursos hidrominerais dos Açores: hidrogeologia e avaliação do potencial sócioeconómico

Tese de Doutoramento, Geologia (Hidrogeologia), 17 de Dezembro de 2013, Universidade dos Açores.

Percurso pedestre no Rio Este: contribuição para a educação ambiental e promoção do ensino experimental

O ensino praticado nas nossas escolas necessita ser mais consentâneo com os princípios e valores veiculados pela Educação Ambiental. Pretende-se, com este trabalho, levar os alunos a percepcionar a natureza com um olhar diferente, a estabelecer uma nova relação com o meio, adoptando uma postura pró-activa na defesa do espaço ribeirinho. Por meio de um percurso investigativo ao longo da margem esquerda de um troço do rio Este, na zona envolvente da Escola, os alunos de uma turma do 5º ano estudaram a flora autóctone existente na zona ribeirinha e recolheram amostras de água onde puderam aplicar processos de tratamento. Os temas abordados pertencem aos conteúdos leccionados nas aulas de Ciências da Natureza. Considerando que estas actividades podem ser importantes ferramentas na educação para o ambiente, elaborou-se para o grupo experimental um caderno de campo, que serviu de orientação ao estudo da flora, realizou-se uma actividade prática no laboratório, com a amostra da água recolhida. Posteriormente aplicou-se um teste, para conhecer o grau de conhecimento adquirido após a actividade e, no final, os alunos responderam a um inquérito para se conhecer o seu grau de satisfação. Ainda que os resultados do teste não mostrem diferenças significativas na aquisição de conhecimento em relação à turma não participante no projecto, a interpretação da paisagem mostrou-se um meio eficaz de envolver os alunos, desenvolver sensibilidades, construir conceitos, promover atitudes positivas que vão de encontro a uma Educação Ambiental ligada à cidadania.

Interpretation of gravity data to delineate structural features connected to low-temperature geothermal resources at Northeastern Portugal

A great number of low-temperature geothermal fields occur in Northern-Portugal related to fractured rocks. The most important superficial manifestations of these hydrothermal systems appear in pull-apart tectonic basins and are strongly conditioned by the orientation of the main fault systems in the region. This work presents the interpretation of gravity gradient maps and 3D inversion model produced from a regional gravity survey. The horizontal gradients reveal a complex fault system. The obtained 3D model of density contrast puts into evidence the main fault zone in the region and the depth distribution of the granitic bodies. Their relationship with the hydrothermal systems supports the conceptual models elaborated from hydrochemical and isotopic water analyses. This work emphasizes the importance of the role of the gravity method and analysis to better understand the connection between hydrothermal systems and the fractured rock pattern and surrounding geology. (c) 2013 Elsevier B.V. All rights reserved.