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The scattering of linear water waves by an infinitely long rectangular structure parallel to a vertical wall in oblique seas is investigated. Analytical expressions for the diffracted potentials are derived using the method of separation of variables. The unknown coefficients in the expressions are determined through the application of the eigenfunction expansion matching method. The expressions for wave forces on the structure are given. The calculated results are compared with those obtained by the boundary element method. In addition, the influences of the wall, the angle of wave incidence, the width of the structure, and the distance between the structure and the wall on wave forces are discussed. The method presented here can be easily extended to the study of the diffraction of obliquely incident waves by multiple rectangular structures. DOI: 10.1061/(ASCE)0733-950X(2006) 132:2(106) CE Database subject headings: Wave diffraction; Water waves; Wave forces; Analytical techniques; Hydraulic structures.

The influence of membrane lipid composition on the molecular activity of a major membrane protein (the sodium pump) was examined as a test of the membrane pacemaker theory of metabolism. Microsomal membranes from the kidneys of cattle (Bos taurus) and crocodiles (Crocodylus porosus) were found to possess similar sodium pump concentrations, but cattle membranes showed a four- to five(old higher enzyme ([Na.sup.+]-[K.sup.+]-ATPase) activity when measured at 37[degrees]C. The molecular activity of the sodium pumps (ATP/min) from both species was fully recoverable when delipidated pumps were reconstituted with membrane from the original source (same species). The results of experiments involving species membrane crossovers showed cattle sodium pump molecular activity to progressively decrease from 3,245 to 1,953 (P < 0.005) to 1,031 (P < 0.003) ATP/min when subjected to two cycles of delipidation and reconstitution with crocodile membrane as a lipid source. In contrast, the molecular activity of crocodile sodium pumps progressively increased from 729 to 908 (P < 0.01) to 1,476 (P = 0.01) ATP/min when subjected to two cycles of delipidation and reconstitution with cattle membrane as a lipid source. The lipid composition of the two membrane preparations showed similar levels of saturated (~31-34%) and monounsaturated (~23-25%) fatty acids. Cattle membrane had fourfold more n-3 polyunsaturated fatty acids (11.2 vs. 2.9%) but had a reduced n-6 polyunsaturate content (29 vs. 43%). The results support the membrane pacemaker theory of metabolism and suggest membrane lipids and their polyunsaturates play a significant role in determining the molecular activity of the sodium pump. endotherms; ectotherms; sodium-potassium-adenosinetriphosphatase; [[sup.3]H]ouabain binding: reconstitution; metabolism

Focuses on the observation of a strong dependence of Si doping on dimer arsenic flux and substrate temperature for GaAs films grown by molecular beam epitaxy. Dependence of Si doping levels on the cracking efficiency and substrate temperature; Correlation between measured carrier concentration of the grown films and cracker temperature.

Analyzes the growth of pseudomorphic zinc sulfur selenide layers on gallium arsenide (GaAs). Application of the molecular beam epitaxy; Dependence of the epilayer quality on zinc exposure to GaAs surface; Defect density of zinc; Formation of atomic scale smooth interface.

Investigates the growth of II-VI blue light-emitting diodes using short period superlattices (SPSL). Properties of SPSL blue light-emitting diodes; Application of molecular beam epitaxy; Components of the SPSL device.

Investigates wide band gap MgZnSSe grown on (001) gallium arsenide by molecular beam epitaxy. Derivation of mirrolike surface and low defect density; Observation of the composition modulation, tweedlike and strain contrasts; Presentation of a miscibility gap at high sulphur and magnesium compositions.

Examines the growth of Cd[sub 1-x]Zn[sub x]S diodes on gallium arsenide substrates by molecular beam epitaxy using elemental zinc, cadmium, and sulfur sources. Analysis of the incorporation competition between cadmium and zinc under different sulfur flux conditions; Sulfur etching of the GaAs substrates generating high density of pits on the surface.

Examines the microstructural study of molecular beam epitaxially grown zinc cadmium sulphide (ZnCdS) epilayers on gallium arsenide (GaAs) substrates. Effect of sulfur attacks on GaAs substrates; Propagation of fit formation in ZnCdS epilayers; Avoidance of pit formation by GaAs substrate capping.

Fabricates low-threshold buried-ridge laser diodes in II-VI semiconductors. Threshold current densities and voltages of the devices; Use of a self-aligned process resulting to a planar surface; Indication of the far-field patterns from the devices.