Методика обработки изображения вращающейся капли при измерении межфазного натяжения жидкостей

Запропоновано методику цифрового оброблення зображення обертової краплі для отримання координат точок контуру обертової краплі, що використовуються для подальшого визначення міжфазного натягу рідин. Проаналізовано вплив різних факторів на результат оброблення зображення.The method digital image processing of spinning drop is offered for determination coordinates spinning drop shape points. Different factors has been analyzed that impacts to result image processing.Предложено методику цифровой обработки изображения вращающейся капли для получения координат точек контура вращающейся капли, что используются для дальнейшего определения межфазного натяжения жидкостей. Сделан анализ влияния разных факторов на результат обработки изображения

Influence of polymer excluded volume on the phase behavior of colloid-polymer mixtures

We determine the depletion-induced phase-behavior of hard sphere colloids and interacting polymers by large-scale Monte Carlo simulations using very accurate coarse-graining techniques. A comparison with standard Asakura-Oosawa model theories and simulations shows that including excluded volume interactions between polymers leads to qualitative differences in the phase diagrams. These effects become increasingly important for larger relative polymer size. Our simulations results agree quantitatively with recent experiments.Comment: 5 pages, 4 figures submitted to Physical Review Letter

Enhancement of Cardiac Store Operated Calcium Entry (SOCE) within Novel Intercalated Disk Microdomains in Arrhythmic Disease

Store-operated Ca2+ entry (SOCE), a major Ca2+ signaling mechanism in non-myocyte cells, has recently emerged as a component of Ca2+ signaling in cardiac myocytes. Though it has been reported to play a role in cardiac arrhythmias and to be upregulated in cardiac disease, little is known about the fundamental properties of cardiac SOCE, its structural underpinnings or effector targets. An even greater question is how SOCE interacts with canonical excitation-contraction coupling (ECC). We undertook a multiscale structural and functional investigation of SOCE in cardiac myocytes from healthy mice (wild type; WT) and from a genetic murine model of arrhythmic disease (catecholaminergic ventricular tachycardia; CPVT). Here we provide the first demonstration of local, transient Ca2+ entry (LoCE) events, which comprise cardiac SOCE. Although infrequent in WT myocytes, LoCEs occurred with greater frequency and amplitude in CPVT myocytes. CPVT myocytes also evidenced characteristic arrhythmogenic spontaneous Ca2+ waves under cholinergic stress, which were effectively prevented by SOCE inhibition. In a surprising finding, we report that both LoCEs and their underlying protein machinery are concentrated at the intercalated disk (ID). Therefore, localization of cardiac SOCE in the ID compartment has important implications for SOCE-mediated signaling, arrhythmogenesis and intercellular mechanical and electrical coupling in health and disease

Overturning established chemoselectivities : selective reduction of arenes over malonates and cyanoacetates by photoactivated organic electron donors

The prevalence of metal-based reducing reagents, including metals, metal complexes, and metal salts, has produced an empirical order of reactivity that governs our approach to chemical synthesis. However, this reactivity may be influenced by stabilization of transition states, intermediates, and products through substrate-metal bonding. This article reports that in the absence of such stabilizing interactions, established chemoselectivities can be overthrown. Thus, photoactivation of the recently developed neutral organic superelectron donor 5 selectively reduces alkyl-substituted benzene rings in the presence of activated esters and nitriles, in direct contrast to metal-based reductions, opening a new perspective on reactivity. The altered outcomes arising from the organic electron donors are attributed to selective interactions between the neutral organic donors and the arene rings of the substrates

Xenobiotic Metabolism in Mice Lacking the UDP-Glucuronosyltransferase 2 Family

UDP-Glucuronosyltransferases (UGTs) conjugate a glucuronyl group from glucuronic acid to a wide range of lipophilic substrates to form a hydrophilic glucuronide conjugate. The glucuronide generally has decreased bioactivity and increased water solubility to facilitate excretion. Glucuronidation represents an important detoxification pathway for both endogenous waste products and xenobiotics, including drugs and harmful industrial chemicals. Two clinically significant families of UGT enzymes are present in mammals: UGT1s and UGT2s. Although the two families are distinct in gene structure, studies using recombinant enzymes have shown considerable overlap in their ability to glucuronidate many substrates, often obscuring the relative importance of the two families in the clearance of particular substrates in vivo. To address this limitation, we have generated a mouse line, termed ΔUgt2, in which the entire Ugt2 gene family, extending over 609 kilobase pairs, is excised. This mouse line provides a means to determine the contributions of the two UGT families in vivo. We demonstrate the utility of these animals by defining for the first time the in vivo contributions of the UGT1 and UGT2 families to glucuronidation of the environmental estrogenic agent bisphenol A (BPA). The highest activity toward this chemical is reported for human and rodent UGT2 enzymes. Surprisingly, our studies using the ΔUgt2 mice demonstrate that, while both UGT1 and UGT2 isoforms can conjugate BPA, clearance is largely dependent on UGT1s

Maternal Plasma 25-Hydroxyvitamin D Concentrations and the Risk for Gestational Diabetes Mellitus

Background: Evidence is accumulating for a role of vitamin D in maintaining normal glucose homeostasis. However, studies that prospectively examined circulating concentrations of 25-hydroxyvitamin D (25-[OH] D) in relation to diabetes risk are limited. Our objective is to determine the association between maternal plasma 25-[OH] D concentrations in early pregnancy and the risk for gestational diabetes mellitus (GDM). Methods: A nested case-control study was conducted among a prospective cohort of 953 pregnant women. Among them, 57 incident GDM cases were ascertained and 114 women who were not diagnosed with GDM were selected as controls. Controls were frequency matched to cases for the estimated season of conception of the index pregnancy. Results: Among women who developed GDM, maternal plasma 25-[OH] D concentrations at an average of 16 weeks of gestation were significantly lower than controls (24.2 vs. 30.1 ng/ml, P<0.001). This difference remained significant (3.62 ng/ml lower on average in GDM cases than controls (P value = 0.018)) after the adjustment for maternal age, race, family history of diabetes, and pre-pregnancy BMI. Approximately 33% of GDM cases, compared with 14% of controls (P<0.001), had maternal plasma 25-[OH] D concentrations consistent with a pre-specified diagnosis of vitamin D deficiency (<20 ng/ml). After adjustment for the aforementioned covariates including BMI, vitamin D deficiency was associated with a 2.66-fold (OR (95% CI): 2.66 (1.01–7.02)) increased GDM risk. Moreover, each 5 ng/ml decrease in 25-[OH] D concentrations was related to a 1.29-fold increase in GDM risk (OR (95% CI): 1.29 (1.05–1.60)). Additional adjustment for season and physical activity did not change findings substantially. Conclusions: Findings from the present study suggest that maternal vitamin D deficiency in early pregnancy is significantly associated with an elevated risk for GDM

Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.

There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions

Властивості нервової системи та психоемоційний стан студентів вищих навчальних закладів ІІІ–ІV рівнів акредитації

Psycho-physiological indices of students have been investigated and analyzed: dynamic working capacity of the nervous system under conditions of time deficit; strength and lability of nervous processes (with application of tapping-test); autogenic parameters of the psycho-emotional state (according with Lusher method). 107 students of humanitarian specialties participated in the research. It has been found out, that medium strength and medium level of lability of the nervous system are being characteristic for students, as well as low level of psycho-emotional stability. Predominance of guys upongirls was reliable according with row of indexes. Lag from the indices of persons, that are specialized in improvement of possibilities of the nervous system and indices of the psycho-emotional state (karate sportsmen), confirms possibility of their development in students by means of karateИсследованы и проанализированы психофизиологические показатели студентов: динамическая работоспособность нервной системы при дефиците времени; сила и лабильность нервных процессов (с применением тэппинг-теста), аутогенные параметры психоэмоционального состояния (по методике Люшера). В исследовании участвовали 107 студентов гуманитарных специальностей. Установлено, что студентам присущи средняя сила и средний уровень лабильности нервной системы, низкая психоэмоциональная стойкость. Преобладание ребят над девушками было достоверным за рядом показателей. Отставание от показателей спортсменов, которые специализируются на совершенствовании возможностей нервной системы и показателей психоэмоционального состояния (спортсменов-каратистов), подтверждает вероятность их развития у студентов средствами каратэДосліджено і проаналізовано психофізіологічні показники студентів: динамічна працездатність нервової системи при дефіциті часу; сила та лабільність нервових процесів (із застосуванням теппінг-тесту), аутогенні параметри психоемоційного стану (за методикою Люшера). У дослідженні брали участь 107 студентів гуманітарних спеціальностей. З’ясовано, що студентам притаманні середня сила та середній рівень лабільності нервової системи, низька психоемоційна стійкість. Переважання хлопців над дівчатами було достовірним за низкою показників. Відставання від показників спортсменів, які спеціалізуються на удосконаленні можливостей нервової системи та показників психоемоційного стану (спортсменів-каратистів), підтверджує можливість їх розвитку у студентів засобами карат