974 resultados para 317-U1354A
Resumo:
The applicability of the Watson Hamiltonian for the description of nonlinear molecules—especially triatomic ones—has always been questioned, as the Jacobian of the transformation that leads to the Watson Hamiltonian, vanishes at the linear configuration. This results in singular behavior of the Watson Hamiltonian, giving rise to serious numerical problems in the computation of vibrational spectra, with unphysical, spurious vibrational states appearing among the physical vibrations, especially in the region of highly excited states. In this work, we analyze the problem and propose a simple way to confine the nuclear wavefunction in such a way that the spurious solutions are eliminated. We study the water molecule and observe an improvement compared with previous results. We also apply the method to the van der Walls molecule XeHe2.
Resumo:
The authors use a growth accounting framework to examine growth of the rapidly developing Chinese economy. Their findings support the view that, although feasible in the intermediate term, China's recent pattern of extensive growth is not sustainable in the long run. The authors believe that China will be able to sustain a growth rate of 8 to 9 percent for an extended period if it moves from extensive to intensive growth. They next compare potential growth in China with historical developments in the United States and the European Union. They discuss the differences in production structure and level of development across the three economies that may explain the countries' varied intermediate-term growth prospects. Finally, the authors provide an analysis of "green" gross domestic product and the role of natural resources in China's growth. © 2009, The Federal Reserve Bank of St. Louis.
Resumo:
A comprehensive study of the Debye-Huckel repulsive and ion wakefield induced attractive potentials around a dust grain is presented, including ion flow. It is found that the modified interaction potential (especially the attractive wakefield force) can cause instability of linear dust oscillations propagating in a dusty plasma crystal composed of dust grains in a horizontal arrangement suspended in the sheath region near a conducting wall (electrode). The dependence of dust lattice modes on the ion flow is studied, revealing instability of dust lattice modes for certain values of the ion flow speed. (C) 2003 Elsevier B.V. All rights reserved.
Resumo:
Drawing from the resource-based view and transaction costs economics, we develop a theoretical framework to explain why small and large firms face different levels of resource access needs and resource access capabilities, which mediate the relationship between firm size and hybrid governance. Employing a sample of 317 venture capital firms, drawn across six European countries, we empirically assess our framework in the context of venture capital syndication. We estimate a path model using structural equation modeling and find, consistent with our theoretical framework, mediating effects of different types of resource access needs and resource access capabilities between VC firm size and syndication frequency. These findings advance the small business literature by highlighting the trade-offs that size imposes on firms that seek to manage their access to external resources through hybrid governance strategies.
Resumo:
Travel literature's inherent intergenericity extends into the realm of the interaesthetic in Nicolas Bouvier's textual and photographic representations of Asia. Although produced as distinct narratives, successive editorial decisions and the layering of these two media in the mind of the reader have transformed Bouvier's already palimpsestic texts into fluid, phototextual constructs. This article will offer ‘contrapuntal’ readings of a selection of Bouvier's texts in relation to the photographs charting his intercultural encounters in China and Japan. Countering the relegation of these photographs to the conventional status of aide-mémoire, the article will consider the shifting relationships of complementarity, tension, or disjuncture between image and text. These relationships are characterised by slippage, subversion and paradox. Text does not ‘load’ image, and images do not illustrate text. Indeed, Bouvier's photographs frequently contest, modify, or debunk the textual narratives. Ultimately, the article will argue that Bouvier's representations of Asia, both textual and visual, offer a challenge to cultural essentialism, to self-other binaries, and to monolithic discourses of otherness.
Resumo:
The Towards a Revolution in COPD Health (TORCH) trial was an international clinical trial of chronic obstructive pulmonary disease (COPD) patients where cause of death was assigned by an independent committee. Comparison of death certificate data and adjudicated cause of death allows a unique opportunity to determine death certificate accuracy and frequency of COPD listing on death certificates of COPD patients. In this analysis, the authors determine the concordance between adjudicated cause of death and primary and secondary cause of death from death certificates. In 317 (80%) of informative deaths, the primary or secondary cause of death from certificates agreed with adjudicated cause of death. Only 229 (58%) of death certificates in these COPD patients listed COPD on the certificate. COPD was not listed on the death certificate in 21% of deaths adjudicated to be caused by COPD exacerbation. Compared with pulmonary causes, the listing of COPD on certificates occurred with less frequency than cardiovascular, cancer and other categories of death. The combined primary and secondary listing on death certificates has good concordance with actual cause of death. COPD is under-reported on death certificates, and this under-reporting is more frequent when the primary cause of death is not pulmonary.
Resumo:
Objective
To examine the extent to which the illness perceptions of Oesophageal cancer survivors and the illness perceptions of their carers explain the survivors' levels of psychological distress (in terms of anxiety and depression symptoms) relative to demographic and biomedical variables and patients' coping strategies.
Method
Everyone registered with the Oesophageal Patients' Association in the UK was mailed a questionnaire booklet containing questions about medical and demographic variables, the Illness Perception Questionnaire-Revised, the Cancer Coping Questionnaire, and the Hospital Anxiety and Depression Scale. Patients were asked to pass a modified version of the Illness Perception Questionnaire-Revised to someone they identified as a carer. Complete responses were received from 317 dyads.
Results
Regression models indicated that the variables measured could explain 56% of the variance in anxiety and 54% of the variance in depression. Patients' illness perceptions explained the majority of this variance. Positive focus coping strategies were also found to be important in explaining psychological well-being. Some of the carers' illness perceptions made a significant contribution to the explanation of the patients' levels of psychological distress, and in some instances, carer perceptions were found to moderate the relationship between patients' perceptions and psychological distress.
Conclusion
The findings suggest that cognition-based interventions could potentially be most effective in minimizing emotional distress among survivors of Oesophageal cancer. This study also shows that these interventions could usefully be delivered at the level of the patient–carer dyad.