Адсорбция водорода на чистых и допированных углеродных нанотрубках: DFT моделирование

Рассматривается адсорбция нескольких молекул водорода на внешней и внутренней поверхности комплекса "углеродная нанотрубка (9,9)@Li". Численные эксперименты проводились в пакете SIESTA в двух приближениях для обменно-корреляционного потенциала: приближении обобщенных градиентов (GGA) и приближении локальной электронной плотности (LDA). Моделирование показало, что добавление атома лития позволяет увеличить энергию адсорбции 3-4 молекул водорода (расположенных в первой координационной сфере Li) по сравнению со случаем сорбции на чистой поверхности углеродной нанотрубки. При этом энергии связи попадают в диапазон 200-700 мэВ/(молекулу Н[2]), обеспечивающий эффективность циклов сорбции/десорбции газа, только в случае внутренней сорбции

The Famenian reservoir limestones on core petrophysical and electron spin resonance data (Southern slope of South-Tatarian Arc)

This paper presents core data on the composition and reservoir properties of the Famenian carbonate rocks in typical well section on the southern slope of South-Tatarian Arc. The core data include structures, minerals, reservoir properties measurements from previous studies and geochemical signs, just received by method of electron spin resonance (ESR). Investigated intervals of 16 and 6 m thicknesses belong to the Famenian stage. The thickest interval is composed of grainstones and packstones. The second interval is composed of mainly packstones. The granulated fossils predominate in the studied limestones. Porous space is controlled by primary structure and also by leaching processes, secondary calcite mineralization and stylolites. The interval of 16 m concludes four layers on thin sections data and reservoir properties. The interval of 6 m belongs to one layer. ESR data have been obtained on 22 samples collected with step 0.6-1.2 m along the section. ESR spectra are characterized by narrow lines, pointing on marine genesis of carbonates. Paramagnetic centers of Mn2+ and SO2- have been observed as typical labels of rocks due by processes of carbonate sedimentation. A symbate behavior of Mn2+ and SO2- contents along the section correlates with reservoir characteristics increasing. A diverse behavior of Mn2+ and SO2- contents corresponds to reservoir characteristics decreasing. It can be explained by the unaltered carbonates in the first case and the altered carbonates in the second case because of the leaching, secondary crystallization, adding of the paramagnetic ions and redistribution of paramagnetic centers in new formed mineral phases

The Tournesian reservoir limestones on core petrophysical and geochemical data (Southern slope of South-Tatarian Arc)

This paper presents core data on the composition and reservoir properties of the Tourneisian carbonate rocks in typical well section on the southern slope of South-Tatarian Arc. The core data include structures, minerals, reservoir properties measurements from previous studies and geochemical signs, just received by method of electron spin resonance (ESR). Investigated interval of 12 m thickness belongs to an upper part of the Tourneisian stage. It is composed of two layers: upper grainstone layer (5 m) and lower packstone layer (7 m). The granulated fossils predominate in the studied limestones. A porous space is controlled by primary structures and also by leaching processes, a secondary calcite mineralization and stylolites. ESR data have been obtained on 21 samples collected with a step 0.4-0.6 m along the section. ESR spectra are characterized by narrow lines, pointing on a marine genesis of the carbonates. Paramagnetic centers of Mn 2+ and SO 2- have been observed as typical features of the rocks due by primary processes of carbonate sedimentation. A spatial distribution of limestones types, its geochemical and reservoir signatures is explained by the sedimentary succession of progradation type. The calcite mineralization and a distribution of Mn 2+ and SO 2- paramagnetic ions have been determined along the section profile simultaneously with reservoir zoning due by facies and a history of hydrocarbons

Characterization of Retinal Function using Microperimetry-Derived Metrics in both Adults and Children with RPGR-Associated Retinopathy

PURPOSE: To investigate microperimetry testing of RPGR-associated retinopathy in a cohort of children and adults. STUDY DESIGN: Prospective observational case series. METHODS: The coefficient of repeatability and intraclass correlation coefficient (ICC) of mean sensitivity (MS) were calculated for mesopic microperimetry. Best-corrected visual acuity (BCVA), contrast sensitivity (CS), MS, total volume (VTOT), and central 3-degree field volume (V3) from volumetric and topographic analyses were acquired. RESULTS: Seventy-six RPGR subjects (53 adults, 23 children) were recruited. The mean follow-up period was 2.8 years. The ICC values for MS, VTOT and V3 were 0.982 dB (95% confidence intervals, CI 0.969 to 0.989), 0.970 dB-sr (95% CI -0.02658 to 0.03691) and 0.986 dB-sr (95% CI 0.978 to 0.991), respectively. The r values for interocular MS, VTOT and V3, were 0.97 (P<0.01), 0.97 (P<0.01) and 0.98 (P<0.01) respectively, indicating strong inter-ocular correlation. The interocular correlation of progression for MS, VTOT and V3 was 0.81 (P<0.01), 0.64 (P<0.01) and 0.81 (P<0.01), respectively. There was no statistically significant difference in the interocular progression rates for MS or VTOT. V3 did show a statistically significant difference. Most patients lost retinal sensitivity rapidly during their second and third decades of life. CONCLUSIONS: The high degree of reproducibility of results and the good interocular correlation lends this modality to accurately monitoring disease progression, as well as supporting validation of the use of MP in assessing the outcomes of gene therapy clinical treatment trials

The usage of a binder system for frozen berries in the manufacture of confectionery

The aim of the research was to create binding systems for confectionery using gelling agents. The possibility of using partially hydrolyzed liquid egg white (egg hydrolyzate) in the binding system of gelling agents (egg hydrolyzate - agar (EG-A), egg hydrolyzate - starch (EG-S)) was determined to obtain the required mechanical characteristics when creating coatings, ornaments or fillers in confectionery with whole berries or pieces of fruit. In this regard, a technology has been developed for the hydrolysis of liquid egg white in the presence of an acidic reagent. The best rheological characteristics of the gelling agent from egg white were obtained under the following hydrolysis conditions: egg white : 1% HCl ratio = 1:2, process temperature - 66°C, duration - 40 minutes, the pH of the egg hydrolyzate was 6.53, the amount of dry solids was 11.78%. The newly created systems with agar (E406, Germany), chemically modified food starch (E1442, Germany) and hydrolyzed egg white (egg hydrolyzate) allow to adjust the properties of the coating for quick-frozen berries used in semi-finished confectionaries or cakes. It is established that the coating for quick-frozen berries, which includes a system consisting of 1% E406 and 0.5% egg hydrolyzate, should be carried out in 2 stages. In the first stage, a 10-minute exposure of the coating, which has a tensile strength of 580 g cm-2 , allows to create a strong capsule around the berry, which prevents the processes of destruction from proceeding. The second stage is necessary to obtain a uniform surface coating of the semi-finished mix from the berries. In this case, the tensile strength of the coating should be 480 g cm-2 . The system created from the E1442 and egg hydrolyzate gelling agents was also used in 2 stages when making cakes, which were subsequently baked at 180 °C. The content of the binding system in the coating applied to the test substrate was 6.9–7.7%, the effective viscosity of the coating was 120–180 Pa s. The content of the binding system in the coating of the surface of the berries in the second stage was 5.2–6.3% with effective viscosity values of 50–90 Pa s. Semi-finished berry products and ready-made baked cakes, produced with developed binding systems, can be stored at -8 °C for 10 to 12 days. After refrigerated storage, the separated moisture was not observed in the test samples. The absence of the phenomenon of syneresis with the indicated proportions of the introduction of gelling agents in coating systems has been established

Objective Evaluation of Proliferative Diabetic Retinopathy Using OCT

PURPOSE: To present the routine use of OCT and OCT angiography (OCTA) for the objective diagnosis and monitoring of proliferative diabetic retinopathy (PDR). DESIGN: Retrospective, observational case series. PARTICIPANTS: Patients with diabetic retinopathy imaged using a standardized PDR protocol. METHODS: Patients routinely imaged with a standardized PDR protocol between March 2017 and January 2019 were included. This included a 12×9-mm structural OCT volume centered on the macula and a 6×6-mm OCTA scan centered on the optic nerve head obtained using a Topcon swept-source system (DRI OCT-1 Triton, Topcon, Tokyo, Japan). Ultra-widefield fluorescein angiography (FA) was also performed when clinically indicated. The ground truth for each case was determined by merging the findings from biomicroscopy and imaging modalities to generate the maximum level of detection for each finding. MAIN OUTCOME MEASURES: Detection rates of new-onset, regression, and reactivation of neovascularization of the disc (NVD) and neovascularization elsewhere (NVE) using different modalities (biomicroscopy/color photography, structural OCT, B-scan OCTA, en face OCTA). Detection of progression of tractional retinal detachment (TRD). RESULTS: A total of 383 eyes of 204 patients were evaluated. After excluding patients without PDR or with insufficient image quality, 47 eyes of 35 patients were included. For the detection of new-onset NVD and NVE, structural OCT had the highest detection rate (100%) of all modalities. However, for the detection of regression or reactivation of neovascularization (NV), B-scan OCTA had the highest detection rate (100%). Structural OCT detected regression only in 45.5% of cases, resulting in a low detection rate of reactivation (12.5%). Among 10 eyes with TRD, OCT detected fovea-threatening TRD during follow-up in 7 eyes, resulting in vitrectomy. CONCLUSIONS: This study demonstrates the utility of novel multimodal imaging in the daily management of patients with PDR. Posterior pole structural OCT had the best detection rate for NV, and B-scan OCTA showed the most potential for objective monitoring of disease after treatment

Purinergic regulation of rat heart function in ontogeny

The effect of exogenous ATP and its analogs on heart function was studied in 14-100-day-old rats. Extracellular purines had a positive chronotropic effect on the heart. Intravenous administration of exogenous ATP and its stable analogs induced a dose-dependent increase in heart rate depending on animal age. The analysis of isometric contraction of myocardial strips demonstrated a dose-dependent positive inotropic effect of ATP. The family and subtype of the P2 receptors realizing the positive chronotropic and inotropic effects were identified using selective agonists and blockers. P2X receptors demonstrated the highest sensitivity during early postnatal ontogeny. The age-related pattern of the receptor response to exogenous purines indicated the heterochronic maturation of P2X and P2Y receptors in the myocardium. © 2008 MAIK Nauka

Dynamics of hormones influencing the power exchange at women with obesity at decrease in weight of the body

Work purpose: to study level of hormones influencing appetite and a power exchange at women with obesity initially and after decrease in weight of a body against reception sibutramini. Materials and methods: in research 56 women are included in middle age 42,9 (36,8; 49,3) years, IMT 34,6 (29,8; 37,3) kg/sq.m. To all patients clinical, laboratory and tool examination was conducted. Hormonal research, included: definition serotonini, leptini, ghrelini, endotelina-1, growth hormone. Results: at women with obesity the giperleptinemiya, the raised level serotonini, endotelina-1 is revealed. Decrease in weight of a body against reception sibutramini was accompanied by decrease in level leptin, ghrelin, endotelina-1, serotonin. Conclusions: in patients with obesity have significantly increased levels of leptin, serotonin, ghrelin compared with women of normal weight. Weight reduction of 5% from initial led to a significant improvement in levels of endothelin-1, adiponectin. The use of sibutramine do not have a negative impact on the level of endothelin-1 and adiponectin and more effectively in patients with a BUI of less than 35 kg/m2. Slow weight loss is associated with high levels of leptin, ghrelin, serotonin.Цель работы: изучить уровень гормонов, влияющих на аппетит и энергообмен, у женщин с ожирением исходно и после снижения массы тела на фоне приема сибутрамина. Материалы и методы: в исследование включено 56 женщин в возрасте 42,9 (36,8;49,3) лет, с ИМТ 34,6 (29,8:37,3) кг/м2. Всем пациенткам проводилось клиническое, лабораторное и инструментальное обследование. Гормональное исследование включало определение серотонина, лептина, грелина, эндотелина-1, гормона роста. Результаты: у женщин с ожирением выявлена гиперлептинемия, повышенный уровень серотонина, эндотелина-1. Уменьшение массы тела на фоне приема сибутрамина сопровождалось снижением уровня лептина, грелина, эндотелина-1, серотонина. Выводы: у пациенток с ожирением имеются значимо повышенные уровни лептина, серотонина, грелина по сравнению с женщинами нормального веса. Уменьшение веса на 5% от исходного привело к достоверному улучшению уровней эндотелина-1, адипонектина. Применение сибутрамина не оказывает негативного влияния на уровень эндотелина-1 и адипонектина и более эффективно у пациенток с ИМТ менее 35 кг/м2. Медленное снижение массы тела связано с высоким уровнем лептина, грелина, серотонина