1,751 research outputs found

    PND43 Cost-Effectiveness of Subcutaneous Verse Intramuscular Interferon Beta-1A In Portugal Based on the Findings of Cochrane Collaboration Review of First-Line Treatments for Relapsing-Remitting Multiple Sclerosis

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    This paper considers the potential impact that the nascent technology of quantum computing may have on society. It focuses on three areas: cryptography, optimization, and simulation of quantum systems. We will also discuss some ethical aspects of these developments, and ways to mitigate the risks

    Impact of COVID-19 outbreak on nurses’ mental health: a prospective cohort study

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    Objectives: To evaluate variations in nurses’ sleep quality and symptoms of depression, anxiety and stress during the COVID-19 outbreak, and to evaluate whether the presence of potential risk factors influenced these symptoms over time. Methods: This prospective cohort study surveyed nurses three times – surveying personal factors, working conditions, family dynamics, and attitude towards COVID-19 – between March 31 and May 4, 2020. Nurses’ mental health was assessed through Depression Anxiety Stress Scales – short version (DASS-21); their sleep quality was assessed through a 5-point Likert scale question. Results: Nurses' sleep quality and symptoms of depression, anxiety and stress presented a positive variation over the COVID-19 outbreak. The only factors which are directly related to the COVID-19 outbreak and that were associated with the positive variation in nurses’ symptoms of depression, anxiety and stress were the fear to infect others and the fear to be infected (higher fear of being infected or to infect someone corresponded to increased symptoms of depression, anxiety and stress). Conclusions: Although the COVID-19 outbreak seems to have had an immediate impact on nurses' mental health, a psychological adaptation phenomenon was also observed. Future research should focus on assessing nurses’ symptoms of depression, anxiety and stress, after the COVID-19 pandemic, in order to compare and contrast the findings with the results of our study.info:eu-repo/semantics/publishedVersio

    Nurses’ mental health during the covid-19 outbreak: a cross-sectional study

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    Objective: To describe nurses’ mental health status during the Covid-19 outbreak and to explore the factors that might accentuate the negative consequences on their mental health. Methods: We conducted an online survey to evaluate demographic variables, working conditions, family dynamics, and mental health variables in nurses working in healthcare settings, in Portugal, during the Covid-19 outbreak. Results: Portuguese nurses presented higher depression, anxiety and stress levels, when compared to the Portuguese general population, during the outbreak. Overall, nurses who did not consider the quantity and quality of personal protective equipment as adequate presented significantly higher levels of depression, anxiety, and stress. Conclusions: Our results suggest that nurses’ mental health status seems to be particularly affected by the Covid-19 outbreak and that some modifiable elements might accentuate the impacts on their mental health.info:eu-repo/semantics/publishedVersio

    Buyer-seller conflict and cooperation in marketing channels: port wine distribution

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    The main purpose of this study is to research buyer-seller conflict and cooperation in distribution channels. Based on a multidimensional case study, eight research hypotheses were formulated. Some quantitative research was conducted, based on a questionnaire sent to 101 port wine producers and distribution companies (61 answered properly – 31 producers and 29 distributors – which gave the authors a 60% rate of response, considered to be very good for these types of studies; those 101 port wine producers and distributors initially chosen were the most important in Europe, considering the volume of production and sales, and constituting, for that reason, a convenience sample). A binary probit model was developed to analyze the data. The results of the study demonstrate that when conflict is ongoing and intense it prevents the development of cooperative relationships. A trustworthy company is more likely to solve conflicts. When trust and adaptation capabilities increase, so does potential cooperation. The results also show that the presence of a foreign sales representative in the team does not exert a negative influence on cooperation. Finally, cooperation can be considered as an important means of developing skills and resources, which can then be applied to existing transaction relationships

    Impact of physical layer impairments on multi-degree CDC ROADM-based optical networks

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    Nowadays, optical network nodes are usually based on reconfigurable optical add/drop multiplexers (ROADMs). Due to exponential growth of internet data traffic, ROADMs have evolved to become more flexible, with multi-degree and their add/drop structures are now more complex with enhanced features, such as colorless, directionless and contentionless (CDC). In this work, the impact of in-band crosstalk, optical filtering and amplified spontaneous emission noise on the performance of an optical network based on multi-degree CDC ROADMs is studied considering 100-Gb/s polarisation division multiplexing quadrature phase-shift keying signals for the fixed grid. We show that, an optical signal can pass through a cascade of 19 CDC ROADMs, based on a route and select architecture with 16-degree, until an optical signal-to-noise ratio (OSNR) penalty of 1 dB due to in-band crosstalk is reached. We also show that the ASE noise addition, due to the increase of the number of CDC ROADMs, is more harmful in terms of OSNR penalty than in-band crosstalk.info:eu-repo/semantics/acceptedVersio

    CDC ROADM design tradeoffs due to physical layer impairments in optical networks

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    In this work, we assess the impact of several physical layer impairments (PLIs) on the performance of optical networks based on colorless, directionless and contentionless reconfigurable optical add/drop multiplexers (ROADMs), through Monte-Carlo simulation, and considering polarization division multiplexing 4 and 16 quadrature amplitude modulation (QAM) signals, at 28 GBaud, for 37.5 GHz optical channels. The PLIs taken into account are the amplified spontaneous emission noise, optical filtering, in-band crosstalk and nonlinear interference noise caused by Kerr effect. A detailed model of the ROADM node is built considering two typical ROADM architectures, broadcast and select (B&S) and route and select (R&S), and two different add/drop structures, multicast switches (MCSs) and wavelength selective switches (WSSs), resulting in four different ROADM node scenarios. Our results have shown that for 16QAM signals, the B&S ROADMs with WSSs-based add/drop structures is the scenario that has the best relation cost/performance, foreseeing its use in metro networks, while for 4QAM signals, the R&S ROADM with WSSs-based add/drop structure scenario allows a larger ROADM cascade at an expectable lower cost anticipating its implementation in long-haul networks

    Aromatic L-Aminoacid Decarboxylase Deficiency A Defect of the Neurotransmitter Metabolism with Severe Neurological Impairment

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    A descarboxilase dos L-aminoácidos aromáticos, um enzima piridoxina dependente, é responsável pela conversão da L-dopa em dopamina e do 5 hidroxitriptofano em serotonina. A deficiência desse enzima, um erro inato do metabolismo dos neurotransmissores, resulta numa doença autossómica recessiva com manifestações neurológicas graves. Os dois casos apresentados de deficiência da descarboxilase dos L-aminoácidos aromáticos, entidade pela primeira vez descrita no nosso país, apresentam características clínicas semelhantes, resultantes da disfunção do metabolismo aminérgico: hipotonia, distonia, atraso no desenvolvimento psicomotor, episódios de movimentos oculógiros, irritabilidade e instabilidade vasomotora. A tomografia computadorizada e a ressonância magnética cerebrais foram normais em ambos os casos. Os exames bioquímicos e o estudo da actividade enzimática permitiram fazer o diagnóstico de deficiência da descarboxilase dos L-aminoácidos aromáticos. O nosso objectivo é chamar a atenção para a necessidade de investigar os defeitos do metabolismo dos neurotransmilissores na presença de Uma doença neurológica crónica sem etiologia conhecida. A importância de colocar este diagnóstico diferencial, o mais precocemente possível, advém das possibilidades de terapêutica, aconselhamento genético adequado e diagnóstico pré-natal, já hoje existentes

    Aluminum matrix texture and particle characterization in Al-Al3Ti FGMs produced by a centrifugal solid-particle method

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    The centrifugal solid-particle method has proved to be effective in producing functionally graded materials (FGMs). In this study, Al-Al3Ti FGMs, were produced by this centrifugal method, from an Al-5 wt % Ti master alloy. Applied centrifugal forces were 30, 60 and 120G (units of gravity). Samples from the outer surface of each specimen were cut and aluminum matrix texture analyzed by Schulz reflection method. Analysis of the resulting pole figures indicates a preferred orientation along the (200) plane for the aluminum matrix crystals. Furthermore, increasing the applied centrifugal force enhances the orientation effect. Al3Ti platelet orientation and area fraction at the samples’ outer surface along three observation planes were also measured. The Al3Ti platelets in the outer region are orientated perpendicular to the centrifugal force direction along two of the observed planes, also an increase in centrifugal force leads to an increase in orientation in those two planes. The intermetallic particle volume fraction also increases with higher applied centrifugal force, although not significantly. A correlation appears to exist between particle orientation and the preferred orientation of the matrix.(undefined
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