Lignocellulosic biomass (LCB) is the most abundantly available bioresource amounting to about a global yield of up to 1. 3 billion tons per year. The hydrolysis of LCB results in the release of various reducing sugars which are highly valued in the production of biofuels such as bioethanol and biogas, various organic acids, phenols, and aldehydes. The majority of LCB is composed of biological polymers such as cellulose, hemicellulose, and lignin, which are strongly associated with each other by covalent and hydrogen bonds thus forming a highly recalcitrant structure. The presence of lignin renders the bio-polymeric structure highly resistant to solubilization thereby inhibiting the hydrolysis of cellulose and hemicellulose which presents a significant challenge for the isolation of the respective bio-polymeric components. This has led to extensive research in the development of various pretreatment techniques utilizing various physical, chemical, physicochemical, and biological approaches which are specifically tailored toward the source biomaterial and its application. The objective of this review is to discuss the various pretreatment strategies currently in use and provide an overview of their utilization for the isolation of high-value bio-polymeric components. The article further discusses the advantages and disadvantages of the various pretreatment methodologies as well as addresses the role of various key factors that are likely to have a significant impact on the pretreatment and digestibility of LCB.

In situ generated Cu nanoparticles catalyze the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH 4 very efficiently at room temperature with good recyclability up to four cycles. The precursor compound, formed by hydrothermal treatment of copper chloride with urea at 120 1C for 6 h, produces Cu nanoparticles on reduction with NaBH 4 during the course of the reaction. The synthesized precursor and the catalyst are characterized by various analytical techniques such as XRD, FTIR, TGA, SEM-EDX, TEM, and UV-visible spectroscopy.

To improve the accuracy of the fragment molecular orbital method (FMO), we introduce a new fragmentation scheme based on using frozen orbitals to describe fractioned bonds. By applying this scheme to a set of polyalanine systems of up to 40 residues for the alpha-helix and beta-strand isomers, we established its accuracy, which is considerably improved compared to the original hybrid orbital projection method used for detaching bonds in FMO. For instance, at the two-body FMO expansion with the 6-311G* basis set, the error was typically reduced 2-4 times, and for 6-31G* the accuracy increase was even larger (10 times in terms of the maximum error). For the Trp-cage protein (PDB file 1L2Y) with many charged residues, a fairly large error was observed, which was shown to become small with a larger fragment size or at the three-body level. Consequently, we applied the new scheme to the adsorption of toluene and phenol on a faujasite zeolite, and we demonstrated that good accuracy can be achieved in reproducing ab initio results.

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Prepubertal and postpubertal patients differ in their response to flutamide. In postpubertal patients, 6 weeks preoperative use is safe and leads to partial tumor regression. Tumor regression from adjacent vital structures may facilitate surgical excision and limit morbidity.

The sheet-like CuO shows enhanced catalytic activity, compared to polycrystalline CuO for the catalytic degradation of methylene blue and methyl orange.

Density functional theory (DFT) studies have revealed the energetically favorable reaction paths for oxidation of CO on Pd(4) cluster. Adsorption of various species such as O(2), 2O, O, CO, CO(2), and coadsorbate combinations, including O(2)+CO, 2O+CO, O+CO, and O+CO(2) on neutral, cationic, and anionic Pd(4) clusters were investigated. The results indicate that Pd(4)(+) and Pd(4) are more effective for catalyzing CO in comparison with Pd(4)(-). It is further observed that dissociated oxygen is a superior oxidant for CO oxidation on Pd(4)(q) (q = 0, 1, -1) than molecular and atomic oxygen.

We have been able to isolate the cyanobacterium Microcystis aeruginosa from water samples of ponds and river where patients of rhinosporidiosis were bathing. It is likely that this cyanobacterium is the causative agents of this disease. The bluish-green cells of M. aeruginosa also have a colorless small cell stage called nanocyte which has been detected in clear waters of all the pond and river samples studied. Both large cells and nanocytes of M. aeruginosa could be recognized inside the round bodies of rhinosporidiosis by light and electron microscopy. Further work on culturing this organism from excised samples and evaluation for drug therapy are in progress. It is hoped that, if therapy becomes available, no surgery would be required for this disease. It is suggested that the waters from ponds and lakes, as well as municipal and recreational waters, be checked for the nanocyte stage of M. aeruginosa. Etiological controversies of rhinosporidiosis have been reasonably solved. The new findings justify a change in the name "rhinosporidiosis" that had been associated with the fungus Rhinosporidium Seeberi.