998 research outputs found

    The flammability of electronic components in spacecraft environments Final report, 15 Mar. - 15 Oct. 1968

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    Mathematical model for combustion at zero gravity in spacecraft environment

    An Outline of a Progressive Resolution to the Euro-area Sovereign Debt Overhang: How a Five year Suspension of the Debt Burden Could Overthrow Austerity

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    The present study puts forward a plan for solving the sovereign debt crisis in the euro area (EA) in line with the interests of the working classes and the social majority. Our main strategy is for the European Central Bank (ECB) to acquire a significant part of the outstanding sovereign debt (at market prices) of the countries in the EA and convert it to zero-coupon bonds. No transfers will take place between individual states; taxpayers in any EA country will not be involved in the debt restructuring of any foreign eurozone country. Debt will not be forgiven: individual states will agree to buy it back from the ECB in the future when the ratio of sovereign debt to GDP has fallen to 20 percent. The sterilization costs for the ECB are manageable. This model of an unconventional monetary intervention would give progressive governments in the EA the necessary basis for developing social and welfare policies to the benefit of the working classes. It would reverse present-day policy priorities and replace the neoliberal agenda with a program of social and economic reconstruction, with the elites paying for the crisis. The perspective taken here favors social justice and coherence, having as its priority the social needs and the interests of the working majority

    Fingering Instability in Combustion

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    A thin solid (e.g., paper), burning against an oxidizing wind, develops a fingering instability with two decoupled length scales. The spacing between fingers is determined by the P\'eclet number (ratio between advection and diffusion). The finger width is determined by the degree two dimensionality. Dense fingers develop by recurrent tip splitting. The effect is observed when vertical mass transport (due to gravity) is suppressed. The experimental results quantitatively verify a model based on diffusion limited transport

    Value of speckle-tracking echocardiography changes in monitoring myocardial dysfunction during treatment of sepsis: potential prognostic implications

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    Speckle-tracking echocardiography (STE) has been increasingly used for detection of sepsis-related myocardial dysfunction. However, the impact of strain changes during sepsis treatment has not been defined. This study assessed STE at admission and during the treatment of patients with sepsis to evaluate its changes as a potential factor for predicting in-hospital outcome. This study included 26 patients with sepsis who underwent STE echocardiography on day 1 and 7 during treatment. Myocardial deformation of both ventricles was assessed using global longitudinal strain. The endpoint was in-hospital mortality. The mean age was 51.4±18.3 years, and 54% were female. The average SOFA score at T0 was 8.6±3.8 points and at day 7 was 4.9±4.7 points. The left ventricular (LV) ejection fraction at baseline was 65.6±9.1%, without changes in echocardiographic parameters during treatment. LV and RV longitudinal strain increased significantly in the patients who survived (− 18.8±3.6 at D1 vs − 20.8±2.5 at D7; p=0.003; and −21.3±4.9 at D1 vs − 24.3±5.8 at D7; p=0.035, respectively), whereas strain values remained unchanged in those who died. After adjustment for the SOFA score, RV longitudinal strain at admission was associated with in-hospital mortality [adjusted odds ratio (OR) 0.760; 95% confidence interval (CI) 0.591–0.977; p −0.033]. STE improved significantly after the first week of treatment in patients with sepsis who survived compared with those patients who died during hospitalization. RV strain at admission predicted in-hospital mortality. An improvement in STE during sepsis treatment appears to be a useful tool for predicting in-hospital outcome

    Emulation of Condensed Fuel Flames Using a Burning Rate Emulator (BRE) in Microgravity

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    The Burning Rate Emulator (BRE) is a gaseous fuel burner developed to emulate the burning of condensed phase fuels. The current study details several tests at the NASA Glenn 5-s drop facility to test the BRE technique in microgravity conditions. The tests are conducted for two burner diameters, 25 mm and 50 mm respectively, with methane and ethylene as the fuels. The ambient pressure, oxygen content and fuel flow rate are additional parameters. The microgravity results exhibit a nominally hemispherical flame with decelerating growth and quasi-steady heat flux after about 5 seconds. The BRE burner was evaluated with a transient analysis to assess the extent of steady-state achieved. The burning rate and flame height recorded at the end of the drop are correlated using two steady-state purely diffusive models. A higher burning rate for the bigger burner as compared to theory indicates the significance of gas radiation. The effect of the ambient pressure and oxygen concentration on the heat of gasification are also examined

    Generation y and job market : perceptions of Tourism student of the Federal Fluminense University.

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    Atualmente, nota-se a busca por um modelo de gest?o de pessoas capaz de gerenciar a diversidade presente no espa?o laboral. Considera-se que as empresas apresentam uma pluralidade de indiv?duos com caracter?sticas distintas, tais como ra?a, etnia, g?nero, idade, que influenciam, de maneira significativa, a din?mica das gest?es. Entre a diversidade, destaca-se a quest?o das diferen?as geracionais presentes no universo das organiza??es. Trazendo esses aspectos para a realidade do turismo, nota-se o quanto ? importante compreender como as gera??es, especialmente a Y, est?o se inserindo no mercado de trabalho. Assim, objetiva-se com este trabalho analisar as percep??es da gera??o Y com rela??o ao mercado de trabalho. Para isso , foi realizada uma pesquisa bibliogr?fica e emp?rica, de car?ter qualitativo, empregando-se o m?todo do grupo focal aplicado com alunos da Universidade Federal Fluminense. Os principais resultados obtidos foram o singular modo de trabalhar da gera??o Y nas organiza??es, a incompreens?o das demais gera??es diante das particularidades e atua??es da gera??o Y no contexto organizacional e o distanciamento existente entre o Curso de Turismo da Universidade Federal Fluminense e a realidade do mercado de trabalho.Currently, there is a search for a model of people management that can manage this diversity in the work space. It is considered that companies have a plurality of individuals with different characteristics, such as race, ethnicity, gender, age, among others, which influence significantly the dynamics of its efforts. Bringing these aspects to the reality of Tourism, stands out how important it is to understand how these generations, especially Generation Y, are inserted in the labor market. Thus, the aim of this paper includes researching the perceptions of Generation Y with respect to the labor market. For its fulfillment, a literature and qualitative empirical research was conducted using the method of focus group. The main results were the natural way of working Millennials within organizations, the incomprehension of other generations ahead of the special features and performances of Generation Y in the organizational context and the gap between the Tourism Programme of Universidade Federal Fluminense and reality of the labor market

    Topographical Organization of Mu and Beta Band Activity Associated with Hand and Foot Movements in Patients with Perirolandic Lesions

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    To study the topographical organization of mu and beta band event-related desynchronization (ERD) associated with voluntary hand and foot movements, we used magnetoencephalographic (MEG) recordings from 19 patients with perirolandic lesions. Synthetic aperture magnetometry (SAM) was used to detect and localize changes in the mu (7 - 11 Hz) and beta (13 - 30 Hz) frequency bands associated with repetitive movements of the hand and foot and overlaid on individual coregistered magnetic resonance (MR) images. Hand movements showed homotopic and contralateral ERD at the sensorimotor (S/M) cortex in the majority of cases for mu and to a lesser extent for beta rhythms. Foot movements showed an increased heterotopic distribution with bilateral and ipsilateral ERD compared to hand movements. No systematic topographical segregation between mu and beta ERD could be observed. In patients with perirolandic lesions, the mu and beta band spatial characteristics associated with hand movements retain the expected functional-anatomical boundaries to a large extent. Foot movements have altered patterns of mu and beta band ERD, which may give more insight into the differential functional role of oscillatory activity in different voluntary movements

    Frailty and mortality : Utility of Frail-VIG index in ED short-stay units for older adults

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    Frailty assessment allows the identification of patients at risk of death. The aim here was to study the ability of Frail-VIG Index (FI-VIG) in order to discriminate frailty groups of older adults and garner its correlation with mortality in an Emergency-Department Short-Stay Unit (ED-SSU). Our observational, single-center, prospective study consecutively included patients over 65-years-old admitted between March 1, 2021, and April 30, 2021. 302 patients were included (56 % women), mean age 83 ± 8 years, and 39.1 % of them had a functional disability whilst 16.5 % of them had dementia. A total of 174 patients (58 %) met the frailty criteria (FI-VIG ≥ 0.2): 111 (63.8 %) had mild frailty (FI-VIG 0.2-0.36), 52 (29.9 %) had moderate frailty (FI-VIG 0.36-0.55), and 11 (6.3 %) had advanced frailty (FI-VIG > 0.55). Mortality at 30 days, 6 months, and 1 year was analyzed: no frailty was 6.3 %, 10.8 %, and 12.5 %, respectively; mild frailty was 10.8 %, 22.5 %, and 22.5 %, respectively; moderate frailty was 25 %, 34.6 %, and 42.3 %, respectively; advanced frailty was 36.4 %, 54.5 %, and 3.6 %, respectively. This shows the significant differences between the groups (1-year mortality p < 0.001). Mild frailty vs. non-frail HR was 2.47 (95 %CI 1.12-5.46), moderate frailty vs. non-frail HR was 6.93 (95 %CI 3.16-15.23), and advanced frailty vs. non-frail HR was 11.29 (95 %CI 3.54-36.03). The mean test time was 7 min. There was a strong correlation between frailty degree and mortality at 1, 6, and 12 months. FI-VIG is fast and easy-to-use in this setting. It is routine implementation in ED-SSUs could enable early risk stratification
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