Simultaneous electrolytic production of xylitol and xylonic acid from xylose

A new electrocatalytic process for simultaneous electrolytic production of xylitol and xylonic acid or the corresponding xylonate salts directly from -d-xylose in alkaline solutions of neutral salt as supporting electrolyte has been developed and presented. An electrocatalytically active cathode coating with essentially hydridic features has been employed to enhance Faradaic yields in xylitol production at low current densities by heterogeneous reaction of hydrogenation with H-adatoms, and the entire mechanism has been proved by experimental evidence. An anionic selective anodic coating for titanium substrate was also used to suppress oxygen evolution and optimize the xylonic acid production by direct oxidation with anodically generated bromine, and to carry out the electrode process at almost equilibrium potential. The kinetic effect of specifically adsorbable anions for decreasing cathodic current yields in xylitol production and the resulting necessity for membrane separation of catholyte from anolyte, with proper optimization of the supporting neutral salt composition, has also been emphasized.Paper partly presented at 39th and 40th ISE-Meetings at Glasgow UK, 1988 and Kyoto, Japan, 1989.     

Regulation of S100As Expression by Inflammatory Cytokines in Chronic Lymphocytic Leukemia

The calcium-binding proteins S100A4, S100A8, and S100A9 are upregulated in chronic lymphocytic leukemia (CLL), while the S100A9 promotes NF-κB activity during disease progression. The S100-protein family has been involved in several malignancies as mediators of inflammation and proliferation. The hypothesis of our study is that S100A proteins are mediators in signaling pathways associated with inflammation-induced proliferation, such as NF-κB, PI3K/AKT, and JAK/STAT. The mononuclear cells (MNCs) of CLL were treated with proinflammatory IL-6, anti-inflammatory IL-10 cytokines, inhibitors of JAK1/2, NF-κB, and PI3K signaling pathways, to evaluate S100A4, S100A8, S100A9, and S100A12 expression as well as NF-κB activation by qRT-PCR, immunocytochemistry, and immunoblotting. The quantity of S100A4, S100A8, and S100A9 positive cells (p < 0.05) and their protein expression (p < 0.01) were significantly decreased in MNCs of CLL patients compared to healthy controls. The S100A levels were generally increased in CD19⁺ cells compared to MNCs of CLL. The S100A4 gene expression was significantly stimulated (p < 0.05) by the inhibition of the PI3K/AKT signaling pathway in MNCs. IL-6 stimulated S100A4 and S100A8 protein expression, prevented by the NF-κB and JAK1/2 inhibitors. In contrast, IL-10 reduced S100A8, S100A9, and S100A12 protein expressions in MNCs of CLL. Moreover, IL-10 inhibited activation of NF-κB signaling (4-fold, p < 0.05). In conclusion, inflammation stimulated the S100A protein expression mediated via the proliferation-related signaling and balanced by the cytokines in CLL.     

Cocaprins, β-Trefoil Fold Inhibitors of Cysteine and Aspartic Proteases from Coprinopsis cinerea

We introduce a new family of fungal protease inhibitors with β-trefoil fold from the mushroom Coprinopsis cinerea, named cocaprins, which inhibit both cysteine and aspartic proteases. Two cocaprin-encoding genes are differentially expressed in fungal tissues. One is highly transcribed in vegetative mycelium and the other in the stipes of mature fruiting bodies. Cocaprins are small proteins (15 kDa) with acidic isoelectric points that form dimers. The three-dimensional structure of cocaprin 1 showed similarity to fungal β-trefoil lectins. Cocaprins inhibit plant C1 family cysteine proteases with K_i in the micromolar range, but do not inhibit the C13 family protease legumain, which distinguishes them from mycocypins. Cocaprins also inhibit the aspartic protease pepsin with K_i in the low micromolar range. Mutagenesis revealed that the β2-β3 loop is involved in the inhibition of cysteine proteases and that the inhibitory reactive sites for aspartic and cysteine proteases are located at different positions on the protein. Their biological function is thought to be the regulation of endogenous proteolytic activities or in defense against fungal antagonists. Cocaprins are the first characterized aspartic protease inhibitors with β-trefoil fold from fungi, and demonstrate the incredible plasticity of loop functionalization in fungal proteins with β-trefoil fold.     

Thermally Induced Microstructural Transformations of Fe72Si15B8V4Cu1 Alloy

Thermal stability, mechanism, and kinetics of thermally induced microstructural transformations and their effects on magnetic permeability of Fe₇₂Si₁₅B₈V₄Cu₁ alloy with combined amorphous/nanocrystalline structure were studied. DTA curves revealed two separated thermally activated exothermic events in the temperature ranges from 740 K to 820 K (467 °C to 547 °C) and 870 K to 930 K (597 °C to 657 °C). Crystalline phases present in the as-prepared and thermally treated alloy samples were identified, and their microstructural parameters were determined using XRD, while, to gain further insight into the mechanism of microstructural transformations, AFM and SEM–EDS analyses were performed. Deconvolution of the complex DTA peak into individual steps was conducted, and, in correlation with the results of microstructural analysis, kinetic triplets corresponding to individual transformation steps were determined, allowing for the estimation of the lifetimes of the alloy at different temperatures. Magnetic permeability measurements showed that, in spite of the influence of microstructural transformations on magnetic properties of the alloy, the favorable magnetic properties are retained over relatively a wide temperature range.

     

Determination of 200 °C Isothermal Section of Al-Ag-Ga Phase Diagram by Microanalysis,X-ray Diffraction,Hardness and Electrical Conductivity Measurements

Ternary Al-Ag-Ga system at 200 °C was experimentally and thermodynamically assessed. Isothermal section was extrapolated using optimized thermodynamic parameters for constitutive binary systems. Microstructure and phase composition of the selected alloy samples were analyzed using light microscopy, scanning electron microscopy combined with energy-dispersive spectrometry and x-ray powder diffraction technique. The obtained experimental results were found to be in a close agreement with the predicted phase equilibria. Hardness and electrical conductivity of the alloy samples from four vertical sections Al-Ag₈₀Ga₂₀, Al-Ag₆₀Ga₄₀, Ag-Al₈₀Ga₂₀ and Ag-Al₆₀Ga₄₀ of the ternary Al-Ag-Ga system at 200 °C were experimentally determined using Brinell method and eddy current measurements. Additionally, hardness of the individual phases present in the microstructure of the studied alloy samples was determined using Vickers microhardness test. Based on experimentally obtained results, isolines of Brinell hardness and electrical conductivity were calculated for the alloys from isothermal section of the ternary Al-Ag-Ga system at 200 °C.     

Palm Oil: A New Ethics of Visibility for the Production Landscape

The explosion of the palm oil industry in recent decades has transformed vast swathes of the Malaysian and Indonesian countryside. Milica Topalovic , Assistant Professor of Architecture and Territorial Planning at ETH Zurich, asserts that the resulting agro-industrial landscapes challenge the very concept of what is rural, and considers how such areas should be conceptualised.     

Molar Ratio of Phytic Acid and Zinc During Cereal Flake Production

The phytic acid content and distribution of phosphorus during cereal flaking were determined as well as the level of some minerals, and the molar ratios of phytic acid: zinc were calculated. Statistical analyses showed that there were no differences in the amount of total phosphorus, between oats and wheat and between rye and barley. The phytic/non-phytic phosphorus ratio was about 3 in wheat and oats, about 2 in barley and about 13 in rye. The technological processing did not affect ( P< 0·05) phytic acid content. The molar ratio of phytic acid: zinc for the flakes was only slightly below that of the whole grain, indicating that the technological process, primarily a hydrothermal treatment and flaking, did not improve zinc availability.