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An integral equation method for a boundary value problem arising in unsteady water wave problems
In this paper we consider the 2D Dirichlet boundary value problem for Laplace’s equation in a non-locally perturbed half-plane, with data in the space of bounded and continuous functions. We show uniqueness of solution, using standard Phragmen-Lindelof arguments. The main result
is to propose a boundary integral equation formulation, to prove equivalence with the boundary value problem, and to show that the integral equation is well posed by applying a recent partial generalisation of the Fredholm alternative in Arens et al [J. Int. Equ. Appl. 15 (2003) pp. 1-35]. This then leads to an existence proof for the boundary value problem.
Keywords. Boundary integral equation method, Water waves, Laplace’
Study of a soft lander/support module for Mars missions. Volume 3 - Appendixes Final summary report
Soft lander support module for Mars missions - lunar module radar evaluation and vernier phase simulatio
Nucleon-Nucleon Scattering in a Harmonic Potential
The discrete energy-eigenvalues of two nucleons interacting with a
finite-range nuclear force and confined to a harmonic potential are used to
numerically reconstruct the free-space scattering phase shifts. The extracted
phase shifts are compared to those obtained from the exact continuum scattering
solution and agree within the uncertainties of the calculations. Our results
suggest that it might be possible to determine the amplitudes for the
scattering of complex systems, such as n-d, n-t or n-alpha, from the
energy-eigenvalues confined to finite volumes using ab-initio bound-state
techniques.Comment: 19 pages, 13 figure
Albumin concentrations are primarily determined by the body cell mass and the systemic inflammatory response in cancer patients with weight loss
The association between hypoalbuminemia and poor prognosis in patients with cancer is well recognized. However, the factors that contribute to the fall in albumin concentrations are not well understood. In the present study, we examined the relationship between circulating albumin concentrations, weight loss, the body cell mass (measured using total body potassium), and the presence of an inflammatory response (measured using C- reactive protein) in male patients (n=40) with advanced lung or gastrointestinal cancer. Albumin concentrations were significantly correlated with the percent ideal body weight (r=0.390, p lt 0.05), extent of reported weight loss (r=-0.492, p lt 0.01), percent predicted total body potassium (adjusted for age, height, and weight, r=0.686, p lt 0.001), and logo C-reactive protein concentrations (r=-0.545, p lt 0.001). On multiple regression analysis, the percent predicted total body potassium and log(10) C-reactive protein concentrations accounted for 63% of the variation in albumin concentrations (r(2) = 0.626, p lt 0.001). The interrelationship between albumin, body cell mass, and the inflammatory response is consistent with the concept that the presence of an ongoing inflammatory response contributes to the progressive loss of these vital protein components of the body and the subsequent death of patients with advanced cancer
Follow-up of a suspected excess of brain tumours among Namibian children
The original publication is available at http://www.samj.org.zaTo the Editor: The aim of this follow-up study was to further
investigate a suggested excess of childhood brain tumours
(CBT) among Herero children in Namibia from 1983 to 1988. Incidence rates of primary brain tumours among Herero
children were found to be 4 times higher than rates among
Namibian children in any of the 10 other tribal groups or
among children of European origin.
The causes of CBTs remain largely unknown. The only
established causes are ionizing radiation and predisposing
inherited syndromes. A particularly compelling hypothesis is
that exposure during gestation to N-nitroso compounds
(NOCs) may lead to the development of CBT. This hypothesis
was suggested by experimental work in which 100%
production of nervous system (NS) tumours in rat offspring
resulted from transplacental exposure to the neurocarcinogen
ethylnitrosourea (ENU) or to low levels of the precursor
compounds sodium nitrite and ethyl urea added to the food
and drinking water of pregnant rat
PATENTS, R&D AND LAG EFFECTS: EVIDENCE FROM FLEXIBLE METHODS FOR COUNT PANEL DATA ON MANUFACTURING FIRMS
Hausman, Hall and Griliches (1984) and Hall, Griliches and Hausman (1986) investigated whether there was a lag in the patent-R&D relationship for the U.S. manufacturing sector using 1970¿s data. They found that there was little evidence of anything but contemporaneous movement of patents and R&D. We reexamine this important issue employing new longitudinal patent data at the firm level for the U.S. manufacturing sector from 1982 to 1992. To address unique features of the data, we estimate various distributed lag and dynamic multiplicative panel count data models. The paper also develops a new class of count panel data models based on series expansion of the distribution of individual effects. The empirical analyses show that, although results are somewhat sensitive to different estimation methods, the contemporaneous relationship between patenting and R&D expenditures continues to be rather strong, accounting for over 60% of the total R&D elasticity. Regarding the lag structure of the patents-R&D relationship, we do find a significant lag in all empirical specifications. Moreover, the estimated lag effects are higher than have previously been found, suggesting that the contribution of R&D history to current patenting has increased from the 1970¿s to the 1980¿s.Innovative activity, Patents and R&D, Individual effects, count panel data methods.
ECONOMIC IMPACT EVALUATION OF GLOBAL MARKETING SUPPORT SERVICES - AN EXPORTS ASSISTANCE PROGRAM ON THE ECONOMY OF ARKANSAS
This study determines the impact of Global Marketing Support Services (GMSS) - an exports assistance program in assisting 13 small and medium sized businesses to export. The total impact of exports (direct, indirect and induced effects) on added value, employment, labor income and tax impacts in Arkansas are estimated using Impact Analysis for Planning (IMPLAN).International Relations/Trade,
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