Optimization of inhomogeneous electron correlation factors in periodic solids

A method is presented for the optimization of one-body and inhomogeneous two-body terms in correlated electronic wave functions of Jastrow-Slater type. The most general form of inhomogeneous correlation term which is compatible with crystal symmetry is used and the energy is minimized with respect to all parameters using a rapidly convergent iterative approach, based on Monte Carlo sampling of the energy and fitting energy fluctuations. The energy minimization is performed exactly within statistical sampling error for the energy derivatives and the resulting one- and two-body terms of the wave function are found to be well-determined. The largest calculations performed require the optimization of over 3000 parameters. The inhomogeneous two-electron correlation terms are calculated for diamond and rhombohedral graphite. The optimal terms in diamond are found to be approximately homogeneous and isotropic over all ranges of electron separation, but exhibit some inhomogeneity at short- and intermediate-range, whereas those in graphite are found to be homogeneous at short-range, but inhomogeneous and anisotropic at intermediate- and long-range electron separation.Comment: 23 pages, 15 figures, 1 table, REVTeX4, submitted to PR

Reissner-Nordstrom Black Holes and Thick Domain Walls

We solve numerically equations of motion for real self-interacting scalar fields in the background of Reissner-Nordstrom black hole and obtained a sequence of static axisymmetric solutions representing thick domain walls charged black hole systems. In the case of extremal Reissner-Nordstrom black hole solution we find that there is a parameter depending on the black hole mass and the width of the domain wall which constitutes the upper limit for the expulsion to occur.Comment: 18 pages, 10 figures, accepted for Phys. Rev.

Harnessing the potential of ligninolytic enzymes for lignocellulosic biomass pretreatment

Abundant lignocellulosic biomass from various industries provides a great potential feedstock for the production of value-added products such as biofuel, animal feed, and paper pulping. However, low yield of sugar obtained from lignocellulosic hydrolysate is usually due to the presence of lignin that acts as a protective barrier for cellulose and thus restricts the accessibility of the enzyme to work on the cellulosic component. This review focuses on the significance of biological pretreatment specifically using ligninolytic enzymes as an alternative method apart from the conventional physical and chemical pretreatment. Different modes of biological pretreatment are discussed in this paper which is based on (i) fungal pretreatment where fungi mycelia colonise and directly attack the substrate by releasing ligninolytic enzymes and (ii) enzymatic pretreatment using ligninolytic enzymes to counter the drawbacks of fungal pretreatment. This review also discusses the important factors of biological pretreatment using ligninolytic enzymes such as nature of the lignocellulosic biomass, pH, temperature, presence of mediator, oxygen, and surfactant during the biodelignification process

Environmental movements in space-time: the Czech and Slovak republics from Stalinism to post-socialism

To demonstrate the role of space and time in social movements, the paper analyses the evolution and context of the environmental movement in the Czech and Slovak republics from 1948 to 1998. It shows that the movement's identity was formed under socialism and that political opportunity and resource availability changed markedly over time, as did its organisational and spatial structure. The movement played a significant part in the collapse of the socialist regime, but in the 1990s was marginalised in the interests of building a market economy and an independent Slovakia. Nevertheless a diverse and flexible range of groups existed by the late 1990s. The successive space-times allow analysis of the multiple and changing variables that influence the geography of social movements

Widespread occurrence of expressed fungal secretory peroxidases in forest soils

Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and hemethiolate peroxidases (e. g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e. g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter-and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation

Measurement of IgE Antibody by an Antigen-Binding Assay: Correlation with PK Activity and IgG and IgA Antibodies to Allergens

Abstract A quantitative radioimmunoassay for IgE antibodies (ab) is described. The assay measures IgE antigen-binding activity (BA) by using purified allergens radiolabeled with 125I, IgE myeloma serum as a source of carrier protein, and monospecific goat anti-IgE (anti-IgE) to precipitate the IgE. IgE BA for the Group I protein of rye grass pollen (Rye I) was measured in the serum of patients with grass pollen hay fever who had never received immunotherapy. Values for IgE BA were found to correlate well with radioallergosorbent technique (RAST) results (rs = 0.89, p&amp;lt;0.001). By assaying IgE-rich fractions, pure IgG, and whole serum, we found a good correlation between IgE BA, Prausnitz-Küstner (PK) activity, and total IgE. A positive PK test could be elicited with 0.05 ml of dilutions containing as little as 1 or 2 units IgE BA for Rye I/ml. PK testing was more sensitive than either RAST or the antigen-binding assay. Estimates based on the quantity of antigen bound in antigen excess suggested that 1 unit IgE BA represented 0.1 ng IgE ab. With higher concentrations of antigen (up to 1 µg/ml), however, estimates suggested that 1 unit IgE BA represented as much as 0.4 ng IgE ab. These higher estimates appeared to correlate reasonably well with estimates based on RAST elution or RAST absorption. The assay for IgE BA was directly comparable with assays for IgG BA and IgA BA. Results of these assays on sera from the patients showed that IgG BA for Rye I was detectable in 25 of 25 IgE BA in 24 of 25, and IgA BA in 21 of 25. Quantitatively we found a characteristic pattern IgG BA &amp;gt; IgE BA &amp;gt; IgA BA (geometric mean values 862, 214, and 60.2 units/ml, respectively). In keeping with this there was a highly significant quantitative correlation between IgG BA and IgE BA (r = 0.72, p&amp;lt;0.001). None of the sera from nonallergic persons contained detectable IgA or IgE BA for Rye I; however, 20% of these sera (10 of 48) contained IgG BA.</jats:p