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Highlights: [•] The components do not strongly change the primary mesoporous texture of γ-Al2O3. [•] The nature and bond strength of the oxide precursors generate different S species. [•] Both tungsten reducibility and sulphur stability to oxidation determine the activity. [•] The KNiW system exhibits both features to moderate extent and the highest activity. [ABSTRACT FROM AUTHOR]

This paper is treating the problem of reducing energy consumption through heat integration system of bioreactors for antibiotics production. A scheme for heat integration with two heat tanks providing work in different time intervals is proposed. A practically feasible method for managing the processes of heat integration is designed. The task is formulated in terms of continuous nonlinear programming (NLP). The method has been applied to a real industrial process for the production of antibiotics. [ABSTRACT FROM AUTHOR]

In this study the problem of reduction of energy consumption in bioreactors system of antibiotics production by means of energy integration is considered. An energy integration scheme with two heat storage tanks ensuring the system operation at different time intervals is proposed. An approach for processes management of energy integration is developed. The problem is formulated in the terms of MINLP. The efficiency of proposed approach is illustrated on the example of the industry. [ABSTRACT FROM AUTHOR]

Two series of silver modified Ni-Mg materials were synthesized by precipitation-deposition on SiO2 support derived from two silica sources: diatomite activated at 800°C ( Series a; Mg/Ni = 0.1 and SiO2/Ni = 1.07) and synthetic water glass ( Series b; Mg/Ni = 0.1 and SiO2/Ni = 1.15). The modification with silver was made at three molar Ag/Ni ratios, namely 0.0025, 0.025, and 0.1. The effects of the source of the silica support and the silver presence and content on the nickel state in the silver modified reduced-passivated NiMg/SiO2 precursors of the vegetable oil hydrogenation catalyst were established by X-ray diffraction and X-ray photoelectron spectroscopy techniques. The passivation procedure was applied in order to protect the metallic nickel particles from further oxidation. The crystallization of the formed nickel hydrosilicate phases depends on the source of the silica support, more expressed in the diatomite supported samples. It was shown that the silver modification of the NiMg/SiO2 precursors enhances the reduction of the nickel hydrosilicates accompanied by formation of relatively smaller metallic nickel particles, more pronounced in the water glass supported precursors. The increase of the silver content in the water glass deposited samples is responsible for the metallic nickel dispersion increase. The higher content of the Ni0 particles on the surface of the diatomite deposited samples is in accordance with the higher stability of the larger metallic nickel crystallites to oxidation during the passivation step. On contrary, higher dispersed Ni0 particles on the surface of the water glass supported samples are more susceptible to the oxida [ABSTRACT FROM AUTHOR]

Few years ago the effectiveness of different Lactobacillus strains, with activity against different pathogens, was intensively studied. In particular, by producing metabolites such as acetic and lactic acid and thus lowering the pH, Lactobacillus strains inhibit the growth of bacterial pathogens and sometimes even kill them. In this study were included original Bulgarian dairy lactobacilli. The antibacterial activity against 8 test cultures and 8 clinical isolates was estimated by the agar diffusion method. We observed the inhibitory effect of growth of Bacillus subtilis, Bacillus alvei, Escherishia coli and Pseudomonas aeruginosa strains. The cells-free exponential cultures of non-neutralized (pH 3.9) and neutralized forms of the strain Lactobacillus sp. 50P1 showed highest activity. The active strain was identified as L. helveticus by classical and biochemical tests (API LAB 50CH kit). In addition to some technologically relevant properties the active strain 50P1 showed strong antibacterial effect against clinically isolated Pseudomonas aeruginosa and Bacillus alvei - an agricultural important bee pathogen. In conclusion, our results will form the basis for additional studies and possible further application of characterized L. helveticus 50P1 strain in clinical practice and/or veterinary medicine. [ABSTRACT FROM AUTHOR]

Abstract: One-component samples containing K, Ni, and various concentrations of Mo were prepared by incipient wetness impregnation technique. Bi- and tri- component samples have been prepared from the calcined one- and bi-component samples following the same procedure. The samples were characterized by SSA, FT-IR, DRS and Raman measurements. The decrease of the ratio Ni2+(Td)/Ni2+(Oh) with the increase of Mo loading and the re-dispersion of Mo phase after the Ni addition on the one-component Mo containing samples proved the occurrence of interactions between these components in the bi-component NiMo-containing samples. Most probably Ni–Mo–O surface species with different number of Mo-oxo and Ni-oxo entities are formed, depending on the Ni/Mo atomic ratio. It may be accepted, that the Ni2+ ions are partially localized into the molybdate layer without forming well-defined phases. Two kinds of K+ ions have been determined in the corresponding samples, interacting (“bounded” K+ ions) and not interacting (“free” K+ ions) with the rest of the supported phases. The potassium deposition increased the dispersion of Mo phase and influenced the coordination state of the Mo6+ and Ni2+ ions in the bi-component KMo-, KNi-containing samples and the tri-component KNiMo-containing samples. It provoked partial transformation of the polymeric Mo6+(Oh) species into monomeric Mo6+(Td) ones and Ni2+(Td) species predomination over Ni2+(Oh) ones. Most probably, new complex K–Ni–Mo–O species were formed on the support surface in the case of the tri-component samples. [Copyright &y& Elsevier]

Context: Antioxidant supplements are used for prevention of several diseases.Objective: To assess the effect of antioxidant supplements on mortality in randomized primary and secondary prevention trials. DATA SOURCES AND TRIAL SELECTION: We searched electronic databases and bibliographies published by October 2005. All randomized trials involving adults comparing beta carotene, vitamin A, vitamin C (ascorbic acid), vitamin E, and selenium either singly or combined vs placebo or vs no intervention were included in our analysis. Randomization, blinding, and follow-up were considered markers of bias in the included trials. The effect of antioxidant supplements on all-cause mortality was analyzed with random-effects meta-analyses and reported as relative risk (RR) with 95% confidence intervals (CIs). Meta-regression was used to assess the effect of covariates across the trials.Data Extraction: We included 68 randomized trials with 232 606 participants (385 publications).Data Synthesis: When all low- and high-bias risk trials of antioxidant supplements were pooled together there was no significant effect on mortality (RR, 1.02; 95% CI, 0.98-1.06). Multivariate meta-regression analyses showed that low-bias risk trials (RR, 1.16; 95% CI, 1.04[corrected]-1.29) and selenium (RR, 0.998; 95% CI, 0.997-0.9995) were significantly associated with mortality. In 47 low-bias trials with 180 938 participants, the antioxidant supplements significantly increased mortality (RR, 1.05; 95% CI, 1.02-1.08). In low-bias risk trials, after exclusion of selenium trials, beta carotene (RR, 1.07; 95% CI, 1.02-1.11), vitamin A (RR, 1.16; 95% CI, 1.10-1.24), and vitamin E (RR, 1.04; 95% CI, 1.01-1.07), singly or combined, significantly increased mortality. Vitamin C and selenium had no significant effect on mortality.Conclusions: Treatment with beta carotene, vitamin A, and vitamin E may increase mortality. The potential roles of vitamin C and selenium on mortality need further study. [ABSTRACT FROM AUTHOR]

Abstract: Investigations have been carried out on the changes in the corrosion behaviour of OC4004 stainless steel protected by an electrochemically deposited Ce2O3–CeO2 film. It may be assumed, on the basis of the obtained results, that in addition to exercising a screening effect, the cerium oxides film plays the role of an effective cathode stabilizing the steel passive state, i.e. its corrosion resistance without changing the zones of potentials where the steel is in a stable passive state. It has been concluded that in the cases when the Ce2O3–CeO2-protected stainless steel will be used as a construction material for catalytic converters designed for purification of nitric acid containing emissions, the corrosion will proceed at potentials, where the steel passive state will not be disturbed. Simultaneously, the presence of the Ce2O3–CeO2 coverage screens the accumulation on the SS/Ce2O3–CeO2 surface of iron/iron oxides and hydroxides, which could have a negative effect (as catalyst poisons), on the desired catalytic process. [Copyright &y& Elsevier]

Abstract: The one-, bi- and tri-component (K)(Ni)(Mo)/γ-Al2O3 systems are studied after water–gas shift reaction tests in the presence of sulfur in the feed. The samples are characterized after the calcination procedure (oxidic state) and after the catalytic activity test (tested state) by SSA, XRD, XPS and EPR measurements. The Mo4+, Mo5+ and Mo6+ oxidation states are registered on the surface of the tested samples. The different sulfur species such as: sulfide sulfur, oxysulfides, polysulfides, paramagnetic sulfur and sulfate sulfur are present on the sample surface in the reaction redox environment (CO, H2O, H2S, H2 and CO2 agents). The XPS and EPR characterization of the tested state points to the idea that both the molybdenum reducibility (i.e. the Mo4+/(Mo5+ +Mo6+) and Mo4+/Mo5+ ratios) and the sulfur lability (sulfide/sulfate ratio) represent informative indices in regard to the catalytic properties of the Mo-containing systems in the WGS reaction in case of sulfur presence in the feed mixture. [Copyright &y& Elsevier]

The case of a 72-year-old woman with a bleeding tumour in the region of the left knee is described. The clinical diagnosis was angiosarcoma. The histological examination showed an infiltrating tumour, consisting of two types of cells : stromal cells, resembling young connective tissue cells, and multinucleated giant cells. On the basis of the histological findings the tumour was classified as an osteoclastoma. The authors stress the fact that the tumour developed autochtoneously in the skin, rejecting the theory that the giant-cell tumour results from abnormal hyperplasia of osteoclasts. [ABSTRACT FROM AUTHOR]