A variational formulation is used to calculate the sound absorption in order to incorporate the interaction between several absorbing patches of arbitrary shape. In particular, this formulation is applied to small periodic patches. The absorption characteristics are governed by the radiation impedance, Z(r), which is a function of the absorber's geometry and the incidence angle, together with the

One of the main problems in using parabolic concentrators with standard photovoltaics (PV) cells is the highly non-uniform illumination of the cells. The non-uniform irradiation causes high resistive losses in the standard cells due to their relatively high series resistance. This results in a considerably lowered efficiency. To solve the problem, we introduce three different structured reflectors

An evaluation and review of a structurally related group of fragrance materials. (C) 2007 Published by Elsevier Ltd.

The recycling heparan sulfate (HS)-containing proteoglycan glypican-1 (Gpc-1) is processed by nitric oxide (NO)-catalyzed deaminative cleavage of its HS chains at N-unsubstituted glucosamines. This generates anhydromannose (anMan)-containing HS degradation products that can be detected by a specific antibody. Here we have attempted to identify the intracellular compartments where these products ar

Aquaporins are water channel proteins that facilitate the movement of water and other small solutes across biological membranes. Plants usually have large aquaporin families, providing them with many ways to regulate the water transport. Some aquaporins are regulated post-translationally by phosphorylation. We have previously shown that the water channel activity of SoP1P2;1, an aquaporin in the p

Background: Several studies have found correlations between diabetes and an increased prevalence of periodontitis. Objective: To analyse, in a group of subjects with type 2 diabetes (T2D), (i) the association between medical characteristics and severe periodontal disease and (ii) dental care habits and knowledge of oral health. Methods: One hundred and ninety-one subjects with T2D were examined. B

Inhibition of oxidative metabolism is often found to decrease contractility of systemic vascular smooth muscle, but not to reduce global [Ca(2+)](i). In the present study, we probe the hypothesis that it is associated with an altered pattern of intracellular Ca(2+) oscillations (waves) influencing force development. In the rat tail artery, mitochondrial inhibitors (rotenone, antimycin A, and cyani

A parallel finite element approach for analyzing micromechanical problems with periodic unit cells is discussed. The method uses a direct solution strategy so that general periodic boundary conditions can be treated using a two-step domain decomposition strategy. The speedup results show a good performance of the method on coarse-grained problems, i.e. for cases where the computational work done o

We present the first study of dipole and quadrupole moments of liquid water calculated using coupled cluster/molecular mechanics (COMM) methods. CUMM methods are used to calculate the total dipole moment of the water dimer and the results are compared to the corresponding ab initio quantum mechanical calculations. For liquid water we find that the introduction of polarization effects are very impo

Abstract in UndeterminedThe effects of harvesting on the long-term mass balances of calcium (Ca), magnesium (Mg) and potassium (K) were evaluated on a regional level in Sweden. A new high-resolution weathering database was used together with estimates of total deposition, losses through harvest and leaching. Estimates were made for pine and spruce separately and for two harvesting intensity scenar