859 resultados para American Red Cross
Resumo:
This study examines the cultural value orientations (VOs) of employees (managerial and non-managerial) working in three categories of organizations (professional, technical and local services) in India, Poland, Russia and the USA. The analysis is conducted at both the national and organizational levels. The paper hypothesizes cultural differences at the country level and cultural similarities among employees working for professional and technical oriented organizations and divergence in the VOs of employees working for local services organizations. It also hypothesizes differences in the VOs of managerial and non-managerial employees in the four countries. The investigation has been conducted with the help of a questionnaire survey of 1,852 respondents. The outcomes of the analysis show that there are both cross-country cultural differences and similarities among the VOs of employees of the four nations. Further, significant cultural convergence emerges in the VOs of employees working for both professional and technical organizations, however, no significant cultural similarities or differences are observed for employees of service-based organizations in the four countries. There are some similarities emerging between managerial employees in the research countries. The research contributes to the fields of cross-cultural management, international management and international human resource management.
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Culture, trust and prejudice may impact cross-cultural mentoring relationships among African American students attending colleges in the United States. By recognizing the cultural perceptions and differences that exist, mentors and protégés may develop a better understanding of each other’s culture so as to enhance mentoring outcomes and student success.
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A study of 556 students at colleges and universities in Australia, Hong Kong and Singapore explored the relationship between attitude towards the United States and brand attitudes and preferences. Singaporean student attitudes towards both the US Government and US people were higher than were those of the Australian and Hong Kong students. Coke, Nike and McDonald's were among both the most-liked and disliked US brands among the international students, a finding suggesting that brands may possess both a 'lovemark' status, as described in the literature, and its opposite — 'loathemark' status — within the same demographic group. US brand preference scores did not offer support for the belief that international consumers 'vote with their pocketbooks' by refusing to purchase US brands if they have a negative attitude towards the United States. Among Hong Kong and Singaporean students, favourable attitudes towards the purchase of US brands was found to be positively related to favourability towards the US Government.
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Past studies of software maintenance issues have largely concentrated on the average North American firm. While they have made a substantial contribution to good information system management practice, it is believed that further segmentation of sample data and cross-country comparisons will help to identify patterns of behaviour more akin to many less average organizations in North America and elsewhere. This paper compares the Singapore maintenance scene with the reported North American experience. Comparisons are also made between: Government organizations, Singapore corporations and multinational corporations (MNCs); mainframe and minicomputer installations; and fourth-generation language (4GL) and non-4GL computer installations. Study findings, while in many cases were similar to earlier US studies, do show the importance of Singapore's young application portfolio, the widespread usage of 4GLs and the severe maintenance personnel problems.
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To date, biodegradable networks and particularly their kinetic chain lengths have been characterized by analysis of their degradation products in solution. We characterize the network itself by NMR analysis in the solvent-swollen state under magic angle spinning conditions. The networks were prepared by photoinitiated cross-linking of poly(dl-lactide)−dimethacrylate macromers (5 kg/mol) in the presence of an unreactive diluent. Using diffusion filtering and 2D correlation spectroscopy techniques, all network components are identified. By quantification of network-bound photoinitiator fragments, an average kinetic chain length of 9 ± 2 methacrylate units is determined. The PDLLA macromer solution was also used with a dye to prepare computer-designed structures by stereolithography. For these networks structures, the average kinetic chain length is 24 ± 4 methacrylate units. In all cases the calculated molecular weights of the polymethacrylate chains after degradation are maximally 8.8 kg/mol, which is far below the threshold for renal clearance. Upon incubation in phosphate buffered saline at 37 °C, the networks show a similar mass loss profile in time as linear high-molecular-weight PDLLA (HMW PDLLA). The mechanical properties are preserved longer for the PDLLA networks than for HMW PDLLA. The initial tensile strength of 47 ± 2 MPa does not decrease significantly for the first 15 weeks, while HMW PDLLA lost 85 ± 5% of its strength within 5 weeks. The physical properties, kinetic chain length, and degradation profile of these photo-cross-linked PDLLA networks make them most suited materials for orthopedic applications and use in (bone) tissue engineering.
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Impedance cardiography is an application of bioimpedance analysis primarily used in a research setting to determine cardiac output. It is a non invasive technique that measures the change in the impedance of the thorax which is attributed to the ejection of a volume of blood from the heart. The cardiac output is calculated from the measured impedance using the parallel conductor theory and a constant value for the resistivity of blood. However, the resistivity of blood has been shown to be velocity dependent due to changes in the orientation of red blood cells induced by changing shear forces during flow. The overall goal of this thesis was to study the effect that flow deviations have on the electrical impedance of blood, both experimentally and theoretically, and to apply the results to a clinical setting. The resistivity of stationary blood is isotropic as the red blood cells are randomly orientated due to Brownian motion. In the case of blood flowing through rigid tubes, the resistivity is anisotropic due to the biconcave discoidal shape and orientation of the cells. The generation of shear forces across the width of the tube during flow causes the cells to align with the minimal cross sectional area facing the direction of flow. This is in order to minimise the shear stress experienced by the cells. This in turn results in a larger cross sectional area of plasma and a reduction in the resistivity of the blood as the flow increases. Understanding the contribution of this effect on the thoracic impedance change is a vital step in achieving clinical acceptance of impedance cardiography. Published literature investigates the resistivity variations for constant blood flow. In this case, the shear forces are constant and the impedance remains constant during flow at a magnitude which is less than that for stationary blood. The research presented in this thesis, however, investigates the variations in resistivity of blood during pulsataile flow through rigid tubes and the relationship between impedance, velocity and acceleration. Using rigid tubes isolates the impedance change to variations associated with changes in cell orientation only. The implications of red blood cell orientation changes for clinical impedance cardiography were also explored. This was achieved through measurement and analysis of the experimental impedance of pulsatile blood flowing through rigid tubes in a mock circulatory system. A novel theoretical model including cell orientation dynamics was developed for the impedance of pulsatile blood through rigid tubes. The impedance of flowing blood was theoretically calculated using analytical methods for flow through straight tubes and the numerical Lattice Boltzmann method for flow through complex geometries such as aortic valve stenosis. The result of the analytical theoretical model was compared to the experimental impedance measurements through rigid tubes. The impedance calculated for flow through a stenosis using the Lattice Boltzmann method provides results for comparison with impedance cardiography measurements collected as part of a pilot clinical trial to assess the suitability of using bioimpedance techniques to assess the presence of aortic stenosis. The experimental and theoretical impedance of blood was shown to inversely follow the blood velocity during pulsatile flow with a correlation of -0.72 and -0.74 respectively. The results for both the experimental and theoretical investigations demonstrate that the acceleration of the blood is an important factor in determining the impedance, in addition to the velocity. During acceleration, the relationship between impedance and velocity is linear (r2 = 0.98, experimental and r2 = 0.94, theoretical). The relationship between the impedance and velocity during the deceleration phase is characterised by a time decay constant, ô , ranging from 10 to 50 s. The high level of agreement between the experimental and theoretically modelled impedance demonstrates the accuracy of the model developed here. An increase in the haematocrit of the blood resulted in an increase in the magnitude of the impedance change due to changes in the orientation of red blood cells. The time decay constant was shown to decrease linearly with the haematocrit for both experimental and theoretical results, although the slope of this decrease was larger in the experimental case. The radius of the tube influences the experimental and theoretical impedance given the same velocity of flow. However, when the velocity was divided by the radius of the tube (labelled the reduced average velocity) the impedance response was the same for two experimental tubes with equivalent reduced average velocity but with different radii. The temperature of the blood was also shown to affect the impedance with the impedance decreasing as the temperature increased. These results are the first published for the impedance of pulsatile blood. The experimental impedance change measured orthogonal to the direction of flow is in the opposite direction to that measured in the direction of flow. These results indicate that the impedance of blood flowing through rigid cylindrical tubes is axisymmetric along the radius. This has not previously been verified experimentally. Time frequency analysis of the experimental results demonstrated that the measured impedance contains the same frequency components occuring at the same time point in the cycle as the velocity signal contains. This suggests that the impedance contains many of the fluctuations of the velocity signal. Application of a theoretical steady flow model to pulsatile flow presented here has verified that the steady flow model is not adequate in calculating the impedance of pulsatile blood flow. The success of the new theoretical model over the steady flow model demonstrates that the velocity profile is important in determining the impedance of pulsatile blood. The clinical application of the impedance of blood flow through a stenosis was theoretically modelled using the Lattice Boltzman method (LBM) for fluid flow through complex geometeries. The impedance of blood exiting a narrow orifice was calculated for varying degrees of stenosis. Clincial impedance cardiography measurements were also recorded for both aortic valvular stenosis patients (n = 4) and control subjects (n = 4) with structurally normal hearts. This pilot trial was used to corroborate the results of the LBM. Results from both investigations showed that the decay time constant for impedance has potential in the assessment of aortic valve stenosis. In the theoretically modelled case (LBM results), the decay time constant increased with an increase in the degree of stenosis. The clinical results also showed a statistically significant difference in time decay constant between control and test subjects (P = 0.03). The time decay constant calculated for test subjects (ô = 180 - 250 s) is consistently larger than that determined for control subjects (ô = 50 - 130 s). This difference is thought to be due to difference in the orientation response of the cells as blood flows through the stenosis. Such a non-invasive technique using the time decay constant for screening of aortic stenosis provides additional information to that currently given by impedance cardiography techniques and improves the value of the device to practitioners. However, the results still need to be verified in a larger study. While impedance cardiography has not been widely adopted clinically, it is research such as this that will enable future acceptance of the method.
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Quantum dot - plasmon waveguide systems are of interest for the active control of plasmon propagation, and consequently, the development of active nanophotonic devices such as nano-sized optical transistors. This paper is concerned with how varying aspect ratio of the waveguide crosssection affects the quantum dot - plasmon coupling. We compare a stripe waveguide with an equivalent nanowire, illustrating that both waveguides have a similar coupling strength to a nearby quantum dot for small waveguide cross-section, thereby indicating that stripe lithographic waveguides have strong potential use in quantum dot –plasmon waveguide systems. We also demonstrate that changing the aspect ratio of both stripe and wire waveguides can increase the spontaneous emission rate of the quantum dot into the plasmon mode, by up to a factor of five. The results of this paper will contribute to the optimisation of quantum dot - plasmon waveguide systems and help pave the way for the development of active nanophotonics devices.
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Objective: The purpose of this study was to address (1) the existence of an association between menopausal status and the health-related quality of life (HRQOL) in Australian and Japanese women and (2) the relative contributions of menopausal status, modifiable lifestyle risk factors, health, and sociodemographic factors on HRQOL. Design: The Australian and Japanese Midlife Women's Health Study (AJMWHS) was a multisite, population-based study conducted in 2001 to 2002. Measures were conducted on data collected from a survey questionnaire used for a sample of women from Australia and Japan. HRQOL was assessed with seven subscales from the Short Form-36. Results: The differences seen in physical functioning, general health, and vitality are significant. The results support an effect of country of residence on physical functioning and general health. The impact of menopausal status on HRQOL was significantly associated with bodily pain and role-emotional. The country of residence did have a modifying effect on the relationship between menopausal status and physical functioning. After control for confounders, there was a significant difference between Australian and Japanese women for HRQOL. Menopausal status was not associated with HRQOL in the areas of general health and physical functioning. Modifiable lifestyle risk factors contributed more highly to HRQOL for the Australian women than for the Japanese women. If the women had a lowered body mass index, undertook physical activity, consumed dietary phytoestrogens, and used alcohol, their physical functioning seemed to be better. Differences were seen in the contributions to HRQOL in these areas, with lower body mass index in the Australian women and physical activity in the Japanese women being the highest predictors. Somatic and psychological symptoms seem to negatively affect both Japanese and Australian women's physical functioning, contributing more than sociodemographic factors, menopausal status, and behavioral determinants combined to general health and physical functioning. Conclusions: It is important that that consideration be given to incorporating the same tool within the cross-cultural design of studies so that comparisons between cultures and patterns of healthy aging can be made. The research suggests that there seems to be variations across Australian and Japanese midlife women in some areas of HRQOL and some factors that contribute to these areas.
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The main constituents of red mud produced in Aluminio city (S.P. – Brazil) are iron, aluminium and silicon oxides. It has been determined that the average particle diameter for this red mud is between 0.05 and 0.002mm. It is observed that a decrease in the percentage of smaller particles occurs at temperatures greater than 400°C. This observation corresponds with the thermal analysis and X-ray diffraction (XRD) data, which illustrate the phase transition of goethite to hematite. A 10% mass loss is observed in the thermal analysis patterns due to the hydroxide – oxide phase transitions of iron (primary phase transition) and aluminium (to a lesser extent). The disappearance and appearance of the different phases of iron and aluminium confirms the decomposition reactions proposed by the thermal analysis data. This Brazilian red mud has been classified as mesoporous at all temperatures except between 400 and 500°C where the classification changes to micro/mesoporous.
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A range of varying chromophore nitroxide free radicals and their nonradical methoxyamine analogues were synthesized and their linear photophysical properties examined. The presence of the proximate free radical masks the chromophore’s usual fluorescence emission, and these species are described as profluorescent. Two nitroxides incorporating anthracene and fluorescein chromophores (compounds 7 and 19, respectively) exhibited two-photon absorption (2PA) cross sections of approximately 400 G.M. when excited at wavelengths greater than 800 nm. Both of these profluorescent nitroxides demonstrated low cytotoxicity toward Chinese hamster ovary (CHO) cells. Imaging colocalization experiments with the commercially available CellROX Deep Red oxidative stress monitor demonstrated good cellular uptake of the nitroxide probes. Sensitivity of the nitroxide probes to H2O2-induced damage was also demonstrated by both one- and two-photon fluorescence microscopy. These profluorescent nitroxide probes are potentially powerful tools for imaging oxidative stress in biological systems, and they essentially “light up” in the presence of certain species generated from oxidative stress. The high ratio of the fluorescence quantum yield between the profluorescent nitroxide species and their nonradical adducts provides the sensitivity required for measuring a range of cellular redox environments. Furthermore, their reasonable 2PA cross sections provide for the option of using two-photon fluorescence microscopy, which circumvents commonly encountered disadvantages associated with one-photon imaging such as photobleaching and poor tissue penetration.
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In this study, magnetohydrodynamic natural convection boundary layer flow of an electrically conducting and viscous incompressible fluid along a heated vertical flat plate with uniform heat and mass flux in the presence of strong cross magnetic field has been investigated. For smooth integrations the boundary layer equations are transformed in to a convenient dimensionless form by using stream function formulation as well as the free variable formulation. The nonsimilar parabolic partial differential equations are integrated numerically for Pr ≪1 that is appropriate for liquid metals against the local Hartmann parameter ξ . Further, asymptotic solutions are obtained near the leading edge using regular perturbation method for smaller values of ξ . Solutions for values of ξ ≫ 1 are also obtained by employing the matched asymptotic technique. The results obtained for small, large and all ξ regimes are examined in terms of shear stress, τw, rate of heat transfer, qw, and rate of mass transfer, mw, for important physical parameter. Attention has been given to the influence of Schmidt number, Sc, buoyancy ratio parameter, N and local Hartmann parameter, ξ on velocity, temperature and concentration distributions and noted that velocity and temperature of the fluid achieve their asymptotic profiles for Sc ≥ 10:0.
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As a growing number of nations embark on a path to democracy, criminologists have become increasingly interested and engaged in the challenges, concerns, and questions connecting democracy with both crime and criminal justice. Rising levels of violence and street crime, white collar crime and corruption both in countries where democracy is securely in place and where it is struggling, have fuelled a deepening skepticism as to the capacity of democracy to deliver on its promise of security and justice for all citizens. What role does crime and criminal justice play in the future of democracy and for democratic political development on a global level? The editors of this special volume of The Annals realized the importance of collecting research from a broad spectrum of countries and covering a range of problems that affect citizens, politicians, and criminal justice officials. The articles here represent a solid balance between mature democracies like the U.S. and U.K. as well as emerging democracies around the globe – specifically in Latin America, Africa and Eastern Europe. They are based on large and small cross-national samples, regional comparisons, and case studies. Each contribution addresses a seminal question for the future of democratic political development across the globe. What is the role of criminal justice in the process of building democracy and instilling confidence in its institutions? Is there a role for unions in democratizing police forces? What is the impact of widespread disenfranchisement of felons on democratic citizenship and the life of democratic institutions? Under what circumstances do mature democracies adopt punitive sentencing regimes? Addressing sensitive topics such as relations between police and the Muslim communities of Western Europe in the wake of terrorist attacks, this volume also sheds light on the effects of terrorism on mature democracies under increasing pressure to provide security for their citizens. By taking a broad vantage point, this collection of research delves into complex topics such as the relationship between the process of democratization and violent crime waves; the impact of rising crime rates on newly established as well as secure democracies; how crime may endanger the transition to democracy; and how existing practices of criminal justice in mature democracies affect their core values and institutions. The collection of these insightful articles not only begins to fill a gap in criminological research but also addresses issues of critical interest to political scientists as well as other social and behavioral scientists and scholars. Taking a fresh approach to the intersection of crime, criminal justice, and democracy, this volume of The Annals is a must-read for criminologists and political scientists and provides a solid foundation for further interdisciplinary research.