The digestion of monosaccharide residues of the cell walls of oat and vetch hays by rumen contents in vitro

The extent and pattern of digestion of oat hay (Avena sativa L.) and vetch hay (Vicia sativa L.) monosaccharides by rumen contents was studied in vitro. The ratios of matrix polysaccharides to lignin were 1.25:1 and 3.82:1 in the vetch and oat hays, respectively. Glucose, xylose and uronic acids were the main sugars in both plants, comprising about 90% of the total monosaccharides. Glucose, xylose and arabinose were mainly confined to the cell walls (CW), whereas galactose and uronic acids were found in high proportions in the soluble fraction. Vetch had a particularly high uronic acid content (14.4 g 100 g^?1 DM), of which 71% was pectic material. The ratios of CW-glucose to CW-xylose were 2.23:1 and 3.74:1 in the oat CW and vetch CW, respectively. Based on monosaccharide analyses of the CW material, it is suggested that the degree of branching of the matrix polysaccharides is about twice as high in vetch as in oat hay. Total glucose and xylose were more digestible in oat than in vetch hay, whereas most of the minor sugars and the total uronic acids were more digestible in the vetch. Irrespective of species, CW glucose was more digestible than CW xylose. The digestibilities of CW glucose, CW xylose and CW uronic acid were: 61.0, 55.3, 51.5, 34.3 and 62.7, 42.6 for the oat hay and vetch hay, respectively. Following the pattern of digestion, CW arabinose and CW glucose were digested faster than CW xylose and CW uronic acid, irrespective of plant species. The extent of digestion at 12 h of incubation of these sugars was higher in vetch than in oat hay. It is suggeted that the concentration ratio of rapidly to slowly degradable CW sugars, in a given plant, is a major determinant of the rate of CW digestion by rumen microorganisms.     

Self‐Assembly of Perovskite for Fabrication of Semitransparent Perovskite Solar Cells

This work reports on the preparation of semitransparent perovskite solar cells. The cells transparency is achieved through a unique wet deposition technique that creates perovskite grids with various dimensions. The perovskite grid is deposited on a mesoporous TiO₂ layer, followed by hole transport material deposition and evaporation of a semitransparent gold film. Control of the transparency of the solar cells is achieved by changing the perovskite solution concentration and the mesh openings. The semitransparent cells demonstrate 20–70% transparency with a power conversion efficiency of 5% at 20% transparency. This is the first demonstration of the possibility to create a controlled perovskite pattern using a direct mesh‐assisted assembly deposition method for fabrication of a semitransparent perovskite‐based solar cell.     

Dry Autoclaving for the Nanofabrication of Sulfides,Selenides, Borides,Phosphides, Nitrides,Carbides, and Oxides

This review compiles various nanostructures fabricated by a distinct “dry autoclaving” approach, where the chemical reactions are carried out without solvents; above the dissociation temperature of the chemical precursor(s) at elevated temperature in a closed reactor. The diversity to fabricate carbides (SiC, Mo₂C, WC), oxides (VOx‐C, ZnO, Eu₂O₃, Fe₃O₄, MoO₂), hexaborides (LaB₆, CeB₆, NdB₆, SmB₆, EuB₆, GdB₆), nitrides (TiN, NbN, TaN), phosphides (PtP₂, WP), sulfides (ZnS, FeS/C, SnS/C, WS₂, WS₂/C), and selenides (Zn_1‐xMn_xSe/C, Cd_1‐xMn_xSe/C), with various shapes and sizes is accounted with plausible applications. This unique single‐step, solvent‐free synthetic process opens up a new route in the growing nanomaterials science; owing to its considerable advantages on the existing approaches.     

Activation of a plant plasma membrane Ca2+ channel by TGalpha1, a heterotrimeric G protein alpha-subunit homologue

Trinucleotide repeats in several human genes have been found to undergo spontaneous variation in repeat numbers in succeeding generations. Expansion of the repeat beyond a certain length causes specific pathological disorders. So far, a naturally occurring triplet repeat instability of transcribed sequences has been reported only from humans. However, the signal peptide encoding region of the receptor tyrosine kinase gene Xmrk from fish of the genus Xiphophorus contains a CTG repeat that differs in length even between closely related individuals. The consequence of this variability is signal peptides with shorter or longer hydrophobic core regions reaching, in some individuals, the critical maximum length for functional protein export or even exceeding it. In one stock, animals that are homozygous for such an allele were extremely rare, indicating that the triplet repeat length variability of the Xmrk gene of Xiphophorus may indeed have an influence on the function of the gene product and, under certain conditions, may affect the fitness of the individual.     

Measurement of acoustoelastic coefficients of Rayleigh waves in steel alloys

An ultrasonic technique to determine the acoustoelastic coefficients of Rayleigh waves in steel alloys is described. The technique is based on the measurement of the time of flight of Rayleigh waves over a fixed surface distance as a function of applied stress. Measurements on AISI 1080 carbon steel, AISI 4130 alloy steel, and 316L stainless steel specimens are reported. Time of flight resolution and repeatability as well as temperature effects are discussed insofar as they influence the applicability of ultrasonic methods to the measurement of applied and residual biaxial surface stresses in steel.     

Electrical Characterization of Individual Cesium Lead Halide Perovskite Nanowires Using Conductive AFM

Perovskite nanostructures have attracted much attention in recent years due to their suitability for a variety of applications such as photovoltaics, light-emitting diodes (LEDs), nanometer-size lasing, and more. These uses rely on the conductive properties of these nanostructures. However, electrical characterization of individual, thin perovskite nanowires has not yet been reported. Here, conductive atomic force microscopy characterization of individual cesium lead halide nanowires is presented. Clear differences are observed in the conductivity of nanowires containing only bromide and nanowires containing a mixture of bromide and iodide. The differences are attributed to a higher density of crystalline defects, deeper trap states, and higher inherent conductivity for nanowires with mixed bromide–iodide content.     

Effect of inorganic constituents on chemical oxygen demand—I. Bromides are unneutralizable by mercuric sulfate complexation

Chemical oxygen demand (COD) assays are widely used for the estimation of the organic carbon content of water and wastewater. The procedure is subject to interference by free halogen ions, the oxidation of which creates artificially high COD values. As part of an investigation of the interferences involved in the COD determination of chemical industries wastewaters, we found that mercuric sulfate complexation, the standard procedure for neutralizing the halogen effects, is suitable for chlorides but is not applicable to bromides. This observation is true both in the presence or absence of chloride or ammonia. Care should therefore be exercised in the interpretation of COD data for bromide-containing samples.     

Design methodology of refractive index engineering by implantation of high-energy particles in electro-optic materials

Slab waveguides were constructed in K(1-x)Li(x)Ta(1-y)Nb(y)O(3) crystals by the implantation of (12)C(+4) ions at 30 MeV and (16)O(+5) ions at 30 and 40 MeV. The waveguides were characterized by a prism coupler setup. A refractive index drop of 10.9% was observed in a layer formed by the implantation of (16)O(+5) ions at 30 MeV. The carbon-implanted waveguides were found to be thermally stable after annealing at 450 degrees C. A semiempirical formula for predicting the change in the refractive index given the parameters of the implantation process was developed. It is argued that the combination of the basic implantation process with the semiempirical formula can be developed to become a generic method for constructing complex electro-optic circuits with a wave-guided architecture.     

Inhibition of HSV‐1 Attachment,Entry, and Cell‐to‐Cell Spread by Functionalized Multivalent Gold Nanoparticles

The use of modified nanoparticles in interactions with biological targets is attracting rapidly increasing attention. In this Full Paper, the application of gold nanoparticles capped with mercaptoethanesulfonate (Au‐MES NPs) as effective inhibitors of Herpes simplex virus type 1 infection based on their ability to mimic cell‐surface‐receptor heparan sulfate is described. Mechanistic studies reveal that Au‐MES NPs interfere with viral attachment, entry, and cell‐to‐cell spread, thereby preventing subsequent viral infection in a multimodal manner. The ligand multiplicity achieved with carrier nanoparticles is crucial in generating polyvalent interactions with the virus at high specificity, strength, and efficiency. Such multivalent‐nanoparticle‐mediated inhibition is a promising approach for alternative antiviral therapy.