Preparation of alumina nanoparticle suspensions with narrow particle size distribution

Dynamic light scattering (DLS) was applied to the study of the process of the preparing deaggregated water suspensions of alumina nanopowders with specific surface areas of 20-140 m2/g. Nanopowders were prepared by the electric explosion of wire and laser evaporation and, according to electron microscopy (TEM), consisted of nonagglomerated spherical nanoparticles with lognormal size distribution. According to DLS, nonsedimenting water suspensions of alumina nanoparticles, stabilized by sodium citrate at a 5 mM concentration, contain substantial fraction of aggregates. The dynamics of the change in the mean average size of aggregates under exhaustive ultrasound treatment of suspensions with 10 g/l concentration for 1.5-4 h by two types of ultrasonic processors was studied. It was shown that the mean average size of aggregates exponentially diminishes by 1.5-2 times and the fraction of individual particles in suspension enlarges from 45 to 85%. Sequentially centrifuging the suspension at 18000 g separates the remaining aggregates and results in suspensions of individual alumina nanoparticles. Particle size distributions in these suspensions obtained by TEM and DLS are the same within experimental error. © 2013 Pleiades Publishing, Ltd

ЗМІНА ВЛАСТИВОСТЕЙ СУХИХ МОЛОЧНИХ ПРОДУКТІВ ЗА ВІДНОВЛЕННЯ

The change of properties of dry milk canned food has been researched in the recovery process. Optimum process regimes have been found. The studies have been used dry fat–free milk and dry dessert mixes (dry mixes for ice cream and dry mixes for pudding). The possibility of using different types of solvent (fat–free milk and drinking water) has been researched in the restoration of dry milk products. Solids content in the restored product have been changed from 8,0 % to 20,0 %. The thermal stability and the course of restoration of dry milk canned food were controlled. Use of drinking water in the recovery is optimal to ensure quality of finished products. It has been established that recovery of skimmed milk (to prevent technological risks) must comply solids content of 15,0 %. Organoleptic and physico–chemical parameters become stable for 30–60 minutes for dry dessert mixes; 60–90 minutes – for dry fat–free milk during the recovery of mixes. The densities of the recovered mixes were 1100±4 kg/m3 – for dry mixes for ice cream; 1091±3 kg/m3 – for pudding; 1033±3 kg/m3 – for dry fat–free milk. Dynamic viscosities were 78,1±0.1; 71,3±0.1; 1,6±0,1 Pa∙s∙10–3respectively.Исследовано изменение свойств молочных консервов в процессе восстановления и определены оптимальные режимы процесса. Для анализа были использованы сухое обезжиренное молоко и сухие смеси десертного назначения (сухие смеси для мороженого и сухие смеси для пудинга). Исследована возможность использования различных видов растворителя: обезжиренного молока и воды питьевой – в процессе восстановления сухих консервов. В восстановленном продукте изменяли содержание сухих веществ от 8,0 до 20,0 %. Контролировали термостойкость полученных восстановленных смесей и ход их восстановления. Для обеспечения стабильного качества готовых продуктов оптимальным есть использование для восстановления питьевой воды. Установлено, что восстановление сухого обезжиренного молока для предотвращения технологических рисков целесообразно проводить до содержания сухих веществ в восстановленной смеси 15,0 %. Обнаружено, что восстановленные смеси приобретают стабильные значения органолептических и физико–химических показателей за 30–60 минут для сухих десертных смесей и за 60–90 минут – для сухого обезжиренного молока. Плотность восстановленных смесей составляла 1100±4 кг/м3 – в сухой смеси для мороженого; 1091±3 кг/м3– для пудинга; 1033±3 кг/м3– для сухого обезжиренного молока. Динамическая вязкость составляла 78,1±0,1; 71,3±0,1; 1,6±0,1 Па∙с∙10–3 соответственно.Досліджено зміну властивостей молочних консервів у процесі відновлення та визначено оптимальні режими процесу. У дослідженнях використано сухе знежирене молоко та сухі суміші десертного призначення (сухі суміші для морозива та сухі суміші для пудингу). Досліджено можливість використання різних видів розчинника: знежиреного молока та води питної – у процесі відновлення сухих консервів. Змінювали вміст сухих речовин (від 8,0 до 20, 0 %) у відновленому продукті. Контролювали термостійкість отриманих відновлених сумішей та перебіг їх відновлення. Для забезпечення стабільної якості готових продуктів оптимальним у відновленні є використання питної води. Встановлено, що відновлення сухого знежиреного молока для запобігання технологічних ризиків доцільно проводити до вмісту сухих речовин у відновленій суміші 15,0 %. Дослідження перебігу відновлення виявили, що відновлені суміші набувають стабільних значень органолептичних та фізико–хімічних показників за 30–60 хвилин для сухих сумішей десертного призначення та за 60–90 хвилин – для сухого знежиреного молока. Густина відновлених сумішей становила: 1100±4 кг/м3 – в сухій суміші для морозива; 1091±3 кг/м3 – для пудингу; 1033±3 кг/м3– для сухого знежиреного молока. Динамічна в’язкість становила 78,1±0,1; 71,3±0,1; 1,6±0,1 Па∙с∙10–3 відповідно. &nbsp

EVALUATION OF CYTOKINE-MEDIATED MECHANISMS INVOLVED IN DEVELOPMENT OF RESPIRATORY MUSCLE DYSFUNCTION IN THE PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Respiratory muscle (RM) strength was studied in 85 men with exacerbations of chronic obstructive pulmonary disease (COPD). The strength indicators of expiratory (MEP) and inspiratory pressure (MIP, SNIP) in oral cavity were registered by means of the MicroRPM device (CareFusion, UK), as well as intranasal pressure levels by SNIP test. The measured MEP, MIP и SNIP values were compared to the proper indices. Serum concentrations of cytokines (IL-4, IL-6, IL-10, IL-17A, IL-21, TNFα, IFNγ and TGF-β) were determined. The results of the study were processed by means of canonical analysis and by clustering methods. Expiratory RM dysfunction was recorded in mild COPD, expiratory-inspiratory RM dysfunction was recorded in moderate COPD and the diaphragm dysfunction was recorded in severe COPD. Three groups of patients with different combinations of RM strength indicators and immune parameters were identified by means of cluster analysis. The cytokine profile in the first cluster was characterized by maximal concentrations of IL-17A, IL-21, TNFα and TGF-β, whereas RM strength indexes showed minimal values. In the second cluster, a decrease of RM strength indicators by 25-40% against control was associated with a sharp rise of IL-6, along with moderate increase of IL-21 and TGF-βconcentrations. In the third cluster, maximal levels of IL-6, IL-10 and IFNγwere registered, along with low levels of IL-17A, IL-21 and TGF-β concentrations, whereas MEP, MIP и SNIP values did not sufficiently differ from their levels in second cluster. The results of canonical and correlation analysis indicated to interconnections between either certain cytokines, or their pool with the RM strength indicators, dyspnea severity and functional state of COPD patients, thus suggesting involvement of cytokine-mediated mechanisms in pathogenesis of the respiratory muscle dysfunction

Epistemological models in understanding cultural and civilizational specificity

The article proposes a methodology for linking the formation-evolutionary, cultural-civilizational, ethnological, and cultural-anthropological models in understanding the changes of complicated sociocultural system

The effect of preventive immunotherapy on indicators of cellular immunity of high-class martial art athletes depending on the level of sporting achievements

Objective: to evaluatethe preventive immunotherapy's (PIT) influence on indicators of cellular immunity of highly qualified combat athletes, depending on the level of sporting achievements. Materials and methods: research included 79 sportsmen with average age of 25,2 years, average weight 76,9 kg, sports experience no less than 10 years and sports rank no less than master of sports. Participants were stratified by the level of achievements in sports. The group 1 with highest level of achievements consisted of 31 sportsmen, each of who earned victory or a prize place on biggest international competitions (such as championships of Europe, World and Olympic Games). Remaining 48 participants didn't have such achievements, but theywere a part of national team (Group 2). PIT included probiotic - Fervital, a complex preparation of omega 3-6-9 fatty acids, vitamin-mineral complex - the Alphabet-biorhythm; antioxidant complex - Ubigold Q10 (coenzyme Q + vitamin E); antihypoxant - Hypoxen; sedative - Novo-Passit; adaptogenic drug - Gerimax Ginseng; polyenzyme complex - Wobenzym. Results: there was a great balance of cellular immunity in the group 1 before the PIT due to the higher content of CD4+ and CD19+ cells. A statistically significant increase in the relative content of CD3+ and CD8+ cells and a decrease in the relative and absolute content of CD16+ cells was detected against the background of PIT in the group l. But the group 2, on the contrary, showed an increase in the relative and absolute content of CD16+ cells. Conclusions: the obtained results showed a different reaction in the both groups to the conducted preventive immunotherapy, which, apparently, was due to the initial difference in the biochemical, genetic, psychological potential of athletes of these two groups

Biochemical indicators of sports achievements in highly qualified wrestlers

Objective: to conduct comparative analysis of blood biochemical parameters (urea, ALT, AST, creatinkinase, cortisol, testosterone and testosterone / cortisol ratio) in groups of high­class wrestlers with different levels of sports achievements.Materials and methods: male athletes (n = 78), members of the Russian national team in one of the types of wrestling (the average age is 25.2 (21.5–28.9) years, the average weight is 76.9 (68.4–83.4) kg) were recruited to this study. The examined athletes were divided into two groups according to their sporting achievements. The first one — SHA group (super­high achievements) which included athletes (n = 19) who had victories and prizes at the largest international competitions (European, World, Olympic Games), and the second group — MNT group (members of the national team) which included athletes that did not have similar achievements (n = 59). The following biochemical parameters were studied: urea, creatine kinase, ALT, AST, testosterone, cortisol, anabolic index (AI).Results: the absolute values of all metabolites in the examined athletes were within the reference intervals. Statistically significant differences in most of the biochemical parameters were revealed between the compared groups in terms of the level of sports achievements. The SHA group showed a statistically significant shift in relation to MNT group, in direction of increasing the level of metabolites that characterize the predominance of anabolic processes — ALT, testosterone, AI. Metabolite levels, increase which reflects catabolic processes activity and inadequate or insufficient adaptation processes, in the SHA group were significantly lower than in the MNT group. The above changes of the absolute values of biochemical parameters were confirmed by correlation analysis.Conclusions: the obtained results allow us to state the optimal adaptation of this sport, the adequacy of metabolic processes in the group of highly qualified athletes

Combining specificity determining and conserved residues improves functional site prediction

<p>Abstract</p> <p>Background</p> <p>Predicting the location of functionally important sites from protein sequence and/or structure is a long-standing problem in computational biology. Most current approaches make use of sequence conservation, assuming that amino acid residues conserved within a protein family are most likely to be functionally important. Most often these approaches do not consider many residues that act to define specific sub-functions within a family, or they make no distinction between residues important for function and those more relevant for maintaining structure (e.g. in the hydrophobic core). Many protein families bind and/or act on a variety of ligands, meaning that conserved residues often only bind a common ligand sub-structure or perform general catalytic activities.</p> <p>Results</p> <p>Here we present a novel method for functional site prediction based on identification of conserved positions, as well as those responsible for determining ligand specificity. We define Specificity-Determining Positions (SDPs), as those occupied by conserved residues within sub-groups of proteins in a family having a common specificity, but differ between groups, and are thus likely to account for specific recognition events. We benchmark the approach on enzyme families of known 3D structure with bound substrates, and find that in nearly all families residues predicted by SDPsite are in contact with the bound substrate, and that the addition of SDPs significantly improves functional site prediction accuracy. We apply SDPsite to various families of proteins containing known three-dimensional structures, but lacking clear functional annotations, and discusse several illustrative examples.</p> <p>Conclusion</p> <p>The results suggest a better means to predict functional details for the thousands of protein structures determined prior to a clear understanding of molecular function.</p

Movement Protein Pns6 of Rice dwarf phytoreovirus Has Both ATPase and RNA Binding Activities

Cell-to-cell movement is essential for plant viruses to systemically infect host plants. Plant viruses encode movement proteins (MP) to facilitate such movement. Unlike the well-characterized MPs of DNA viruses and single-stranded RNA (ssRNA) viruses, knowledge of the functional mechanisms of MPs encoded by double-stranded RNA (dsRNA) viruses is very limited. In particular, many studied MPs of DNA and ssRNA viruses bind non-specifically ssRNAs, leading to models in which ribonucleoprotein complexes (RNPs) move from cell to cell. Thus, it will be of special interest to determine whether MPs of dsRNA viruses interact with genomic dsRNAs or their derivative sRNAs. To this end, we studied the biochemical functions of MP Pns6 of Rice dwarf phytoreovirus (RDV), a member of Phytoreovirus that contains a 12-segmented dsRNA genome. We report here that Pns6 binds both dsRNAs and ssRNAs. Intriguingly, Pns6 exhibits non-sequence specificity for dsRNA but shows preference for ssRNA sequences derived from the conserved genomic 5′- and 3′- terminal consensus sequences of RDV. Furthermore, Pns6 exhibits magnesium-dependent ATPase activities. Mutagenesis identified the RNA binding and ATPase activity sites of Pns6 at the N- and C-termini, respectively. Our results uncovered the novel property of a viral MP in differentially recognizing dsRNA and ssRNA and establish a biochemical basis to enable further studies on the mechanisms of dsRNA viral MP functions

DIRAC Experiment and Test of Low-Energy QCD

The low-energy QCD predictions to be tested by the DIRAC experiment are revised. The experimental method, the setup characteristics and capabilities, along with first experimental results are reported. Preliminary analysis shows good detector performance: alignment error via $\Lambda$ mass measurement $m_\Lambda = 1115.6 MeV/c^2$ with $\sigma = 0.92 MeV/c^2$, $p \pi^-$ relative momentum resolution $\sigma_Q \approx 2.7 MeV/c$, and evidence for $\pi^