Percolation transition of hydration water at hydrophilic surfaces

An analysis of water clustering is used to study the quasi-2D percolation transition of water adsorbed at planar hydrophilic surfaces. Above the critical temperature of the layering transition (quasi-2D liquid-vapor phase transition of adsorbed molecules) a percolation transition occurs at some threshold surface coverage, which increases with increasing temperature. The location of the percolation line is consistent with the existence of a percolation transition at the critical point. The percolation threshold at a planar surface is weakly sensitive to the size of the system when its lateral dimension increases from 80 to 150 A. The size distribution of the largest water cluster shows a specific two-peaks structure in a wide range of surface coverage : the lower- and higher-size peaks represent contributions from non-spanning and spanning clusters, respectively. The ratio of the average sizes of spanning and non-spanning largest clusters is about 1.8 for all studied planes. The two-peak structure becomes more pronounced with decreasing size of the planar surface and strongly enhances at spherical surfaces.Comment: 17 pages, 11 figure

Dielectric spectroscopy of water at low frequencies: The existence of an isopermitive point

We have studied the real part of the dielectric constant of water from 100 Hz to 1 MHz. We have found that there is a frequency where the dielectric constant is independent of temperature, and called this the isopermitive point. Below this point the dielectric constant increases with temperature, above, it decreases. To understand this behavior, we consider water as a system of two species: ions and dipoles. The first give rise to the so called Maxwell-Wagner-Sillars effect, the second obey the Maxwell-Boltzmann statistics. At the isopermitive point the effect of both mechanisms in the dielectric response compensate each other.Comment: 4 pages, 4 figures, submitted to Chem. Phys. Let

A Novel Liver-targeted Testosterone Therapy for Sarcopenia in Androgen Deprived Men With Prostate Cancer.

Objective: Androgen deprivation therapy (ADT) reduces muscle and bone mass, increasing frailty in men with prostate cancer. The liver mediates the whole body anabolic effects of testosterone. Based on first-pass metabolism, liver-targeted testosterone treatment (LTTT) entails oral delivery of a small dose of testosterone that does not raise peripheral blood testosterone levels. LTTT reduces blood urea and stimulates protein anabolism in hypogonadal men and postmenopausal women. We investigated whether LTTT prevents loss of lean and bone mass during ADT. Method: A 6-month, double-blind, placebo-controlled study of testosterone 40 mg/day in 50 men. Primary outcome measures were lean mass and bone mineral content (BMC). Testosterone, urea and prostate-specific antigen (PSA) were monitored. Patients were withdrawn if PSA exceeded 4 ng/mL. Results: 42 patients completed the study. Mean (95% CI) testosterone rose during LTTT but not placebo treatment [∆ 2.2 (1.3-3.0) vs -0.7 (-1.5 to 0.2) nmol/L; P < 0.01]. Mean PSA level did not change significantly during either treatment. Blood urea fell [∆ -0.4 (-0.9 to -0.1) mmol/L] during LTTT but not placebo [∆ 0.05 (-0.8 to 0.9) mmol/L]. BMC [∆ 49 (5 to 93) g; P < 0.02] and lean mass [∆ 0.8 (-0.1 to 1.7) kg; P = 0.04) increased compared to placebo. Five patients on LTTT withdrew from increased PSA levels, all returning to baseline levels. Conclusion: LTTT shows promise as a simple therapy for preventing sarcopenia and bone loss during ADT. LTTT may induce reversible PSA rise in some patients. Further studies are required to optimize LTTT dose in ADT. LTTT has potential application in other catabolic states in men and women

Surface critical behavior of fluids: Lennard-Jones fluid near weakly attractive substrate

The phase behavior of fluids near weakly attractive substrates is studied by computer simulations of the coexistence curve of a Lennard-Jones (LJ) fluid confined in a slitlike pore. The temperature dependence of the density profiles of the LJ fluid is found to be very similar to the behavior of water near hydrophobic surfaces (Brovchenko et al. J.Phys.: Cond.Matt. v.16, 2004). A universal critical behavior of the local order parameter, defined as the difference between the local densities of the coexisting liquid and vapor phases at some distance z from the pore walls, Deltarho(z) = (rho_l(z) - rho_v(z))/2, is observed in a wide temperature range and found to be consistent with the surface critical behavior of the Ising model. Near the surface the dependence of the order parameter on the reduced temperature tau = (T_c - T)/T_c obeys a scaling law ~ tau^(beta_1) with a critical exponent beta_1 of about 0.8, corresponding to the ordinary surface transition. A crossover from bulk-like to surface-like critical behavior with increasing temperature occurs, when the correlation length is about half the distance to the surface. Relations between the ordinary and normal transitions in Ising systems and the surface critical behavior of fluids are discussed.Comment: 14 pages, 19 figures, submitted to PR

Enterosorbent based on montmorillonite as a promising tool in the treatment and prevention of intestinal disorders in pigs

The article discusses the treatment and prevention of feed toxicosis of pigs. A composition based on montmorillonite-containing minerals is considered as a promising enterosorbent in combination with the drug vievitin in the treatment of pig dysentery. Studies have shown that the complex use of vievitin with a sorbent by giving individually in 100 ml of drinking water at doses of 5.6 (second group) and 11.1 (third group) mg/kg body weight for vievitin and 400 mg/kg body weight bodies for the sorbent provided a high therapeutic effect in the treatment of piglets suffering from dysentery. Recovery, respectively, was 90.8 an

DEVELOPMENT OF RESOURCE-SAVING TECHNOLOGY OF PROCESSING OF TECHNOGENIC RAW MATERIALS FOR EXTRACTION OF VALUABLE COMPONENTS AT METALLURGICAL PROCESSING

The paper deals with the problem of the use of dispersed metal-containing waste. A method of dust-like waste treatment is proposed, which is characterized by low energy consumption and high productivity. The high efficiency of the extraction of metal component from the agglomerated materialВ работе рассмотрена проблема использования дисперсных металлсодержащих отходов. Предложен способ окускования пылевидных отходов, который отличается низкими энергозатратами и высокой производительностью. Показана высокая эффективность извлечения металлического компонента из окускованного материала

EXTRUSION PRODUCTION OF BRIQUETTES BASED ON PEAT RAW MATERIALS

The paper presents the importance of using energy from local fuels, including peat. Considered use of peat briquettes and briquettes based on peat and various carbon fillers. It is shown that the best quality indicators is the output of using petroleum coke.В работе изложена важность использования в энергетике местных видов топлива, включая торф. Рассмотрено использование, как торфяных брикетов, так и брикетов на основе торфа и различных углеродистых наполнителей. Показано, что наилучшие качественные показатели имеет продукция с использованием нефтяного кокса

ВЛИЯНИЕ ОЖИРЕНИЯ НА РАЗВИТИЕ И ПРОГРЕССИЮ ЗЛОКАЧЕСТВЕННЫХ НОВООБРАЗОВАНИЙ: ОБЗОР СОВРЕМЕННЫХ ДАННЫХ И НОВЫХ ТЕРАПЕВТИЧЕСКИХ МИШЕНЕЙ

Background. Type 2 diabetes mellitus, obstructive sleep apnea, osteoarthritis and certain types of cancer are known to correlate with obesity. The mechanisms underlying the link between metabolic disorders and cancer remain obscure, yet assuming a potentially important role of reduced insulin sensitivity, altered glucose metabolism in tumor cells (the so-called Warburg effect), changes in the spectrum of secreted adipokines or interaction with their cognitive receptors as well as changes in steroid sex hormone production.Material and methods. A search for articles published in peer-reviewed journals indexed in pubmed, Wos, scopus and Rsci was carried out. More than 150 articles devoted to the study of the relationship between metabolic disorders and tumor progression were analyzed, of which 69 were included in this review.Results. The main strategy of anticancer therapy is to suppress the proliferation of tumor cells and metastasis. However, one should take into consideration a significant role of additional factors that can enhance side effects of anticancer therapy, ensure the resistance of tumor cells to chemotherapy or change cancer cell metabolic profile. New data recently emerging in the literature indicate an important function of proteins such as t-cadherin and urokinase receptor (upar) and their possible involvement in the regulation of tumor cell metabolism, in particular, sensitivity to insulin and adipose tissue hormones. The review encompasses recent data on the involvement of t-cadherin and upar in the regulation of metabolism and proposes a model explaining the relationship between these proteins and metabolic disorders associated with the processes of carcinogenesis and chemoresistance of cancer cells.Conclusion. Understanding of the factors and mechanisms that support obesity and metabolic disorders is relevant both for the development of cancer preventive measures and optimization of therapeutic strategies for combating cancer.Актуальность. Известно, что диабет 2-го типа, синдром обструктивного апноэ сна, остеоартроз и ряд злокачественных новообразований коррелируют с ожирением. Механизмы, обусловливающие взаимосвязь метаболических нарушений с возникновением злокачественных опухолей, пока неизвестны; значительную роль может играть изменение чувствительности к инсулину и факторам роста, изменение спектра секретируемых адипокинов или особенности их взаимодействия с рецепторами, изменение содержания стероидных половых гормонов в организме, а также особенности метаболизма глюкозы в опухолевых клетках (так называемый эффект Варбурга).Материал и методы. Проведен поиск источников, включая научные, клинические и обзорные статьи, опубликованные в рецензируемых журналах, индексируемых в pubmed, Wos, scopus и РИНЦ. Проанализировано более 150 статей, посвященных изучению взаимосвязи метаболических нарушений с опухолевой прогрессией, из которых 69 включены в данный обзор.Результаты. Основная стратегия лечения опухолевых заболеваний заключается в подавлении пролиферации опухолевых клеток и процессов метастазирования. Возможно, что значительную роль в этих процессах играет ряд факторов, способных усиливать побочные эффекты противоопухолевой терапии, поддерживать резистентность опухолевых клеток или изменять их метаболический профиль. Имеются новые данные о функции таких белков, как Т-кадгерин и рецептор урокиназы (upaR), и их возможном участии в регуляции метаболизма опухолевых клеток, в частности чувствительности к инсулину и гормонам жировой ткани. Помимо адипокинов как уже известных посредников, участвующих в канцерогенезе, в обзоре описаны новые данные о роли Т-кадгерина и урокиназного рецептора upaR в регуляции обменных процессов. Предложена модель, объясняющая взаимосвязь этих белков и метаболических нарушений, ассоциированных с процессами канцерогенеза и химиорезистентности опухолевых клеток.Заключение. Понимание факторов и механизмов, поддерживающих ожирение и нарушения метаболизма, с точки зрения их роли в канцерогенезе актуально как для разработки профилактических мер, так и для оптимизации терапевтических стратегий борьбы с опухолевыми заболеваниями