Self-Assembly of Supramolecules Consisting of Octyl Gallate Hydrogen Bonded to Polyisoprene-block-poly(vinylpyridine) Diblock Copolymers

Synchrotron radiation was used to investigate the self-assembly in two comb-shaped supramolecules systems consisting of octyl gallate (OG), i.e., 1-octyl-3,4,5-trihydroxybenzoate, hydrogen bonded to the pyridine groups of polyisoprene-block-poly(vinylpyridine) diblock copolymers. In the case of the 1,2-polyisoprene-block-poly(4-vinylpyridine)(OG)x system, self-assembly was only observed for x ≥0.5, where x denotes the number of OG molecules per pyridine group. For x = 0.5, 0.75, 1.0, and 1.2 the system self-assembled in the form of hexagonally ordered cylinders of P4VP(OG) throughout the entire temperature range of 25-200 °C investigated. For the 1,4-polyisoprene-block-poly(2-vinylpyridine)(OG)x system, on the other hand, a considerably more complex phase behavior was found, including the formation of cubic, hexagonally ordered cylinders and lamellar morphologies. In this case several order-order transitions were observed as a function of temperature, including a lamellar to lamellar transition involving a collapse of the layer thickness. The absence of hydrogen bonding between the octyl gallate molecules and the pyridine groups at elevated temperatures is argued to be a key factor for many of the phenomena observed.

Modern state and prospects of dermatoglyphics research in practice of medical-psychological examination of students and youth

The modern state and prospects of the medico-psychological examination of students and young people are analysed by a dermatoglyphics that allows drawing up the psychological portrait of a person. On the basis of typology of digital dermatoglyphics the development of the criteria system for prognostic estimation of physical capabilities of a human being is possible. According to the ratio of norm and pathology areas of the skin markings the hereditary diseases for future posterity, developmental abnormalities, different gene mutations, congenital development defects (limbs development defects as the special case), gender anomalies (sex determination), possible lethal cases, chromosome diseases and other cases can be forecasted with 99 % confidence

Redox-induced change in the ligand coordination mode

© 2014 American Chemical Society. The reaction of cobalt(II) pivalate with a spin-labeled Schiff base (HL1) in organic solvents formed trinuclear complex [Co3(Piv)2L1 2L2 2]·Solv (Solv is Me2CO and/or C7H16 and CH3CN) containing both nitroxide L1 and the product of its single-electron reduction, nitrone L2. The formation of [Co3(Piv)2L1 2L2 2] was a consequence of an unusual phenomenon, which we called "redox-induced change in the ligand coordination mode". A reduction of L1 to L2 led to a change in the set of donor atoms and even in the size of the metallocycle. This phenomenon was also found for mononuclear [CrL1 2L2] and [FeL1 2L2]·Me2CO

Dynamics of nonequilibrium quasiparticles in a double superconducting tunnel junction detector

We study a class of superconductive radiation detectors in which the absorption of energy occurs in a long superconductive strip while the redout stage is provided by superconductive tunnel junctions positioned at the two ends of the strip. Such a device is capable both of imaging and energy resolution. In the established current scheme, well studied from the theoretical and experimental point of view, a fundamental ingredient is considered the presence of traps, or regions adjacent to the junctions made of a superconducting material of lower gap. We reconsider the problem by investigating the dynamics of the radiation induced excess quasiparticles in a simpler device, i.e. one without traps. The nonequilibrium excess quasiparticles can be seen to obey a diffusion equation whose coefficients are discontinuous functions of the position. Based on the analytical solution to this equation, we follow the dynamics of the quasiparticles in the device, predict the signal formation of the detector and discuss the potentiality offered by this configuration.Comment: 16 pages, 5 figures Submitted to Superconducting Science and Technolog

Дыхательная реабилитация у больных вирусной пневмонией на фоне новой коронавирусной инфекции

Pulmonary rehabilitation in COVID-19 patients with pneumonia is associated with better treatment outcomes. However, existing protocols have never been evaluated in randomized control studies. The aim. To evaluate the effectiveness of newly-developed pulmonary rehabilitation protocol compared to basic Russian COVID-19 guidelines for patients with oxygenation index (OI) between 200 and 400 points without IMV. Methods. Based on literature reviews and own clinical experience, standard rehabilitation protocol was designed and tailored for specific needs of low-OI patients. Two clinical centers participated in the study and included total 73 patients in main group. Control group included 73 retrospective patients based in propensity score; this patients received standard protocol of early pneumonia activation from official COVID-19 guidelines. Ten-days clinical outcomes were assessed based on parameter distribution type. Results. Evidence show significant difference in required time of continuous oxygen support in (5.1 ± 3.3 vs 8.0 ± 4.6 days for main and control group respectively. Main group also had mildly better functional. We’ve observed less mortality in main group, but attribute it not to the program, but for growing experience of health professionals and decreased loads on health system. Malignancy as comorbidity was considered a significant cofactor also. Conclusion. New pulmonary rehabilitation protocol improves clinical outcomes in critical COVID-19 patients by decreasing the demand fox oxygen support.При использовании дыхательной реабилитации при пневмонии, ассоциированной с новой коронавирусной инфекцией (НКИ), отмечено улучшение результатов лечения. Однако типовые протоколы дыхательной реабилитации для тяжелых форм коронавирусной пневмонии по данным рандомизированных исследований до настоящего момента не оценивались. Целью рандомизированного клинического исследования, проведенного в 2 клинических центрах, явилось определение эффективности протокола дыхательной реабилитации у больных с индексом оксигенации < 400 и > 200 при самостоятельном дыхании или кислородной поддержке по сравнению с пациентами, у которых реабилитация не проводилась. Материалы и методы. В исследовании приняли участие пациенты (n = 146) с ДН, отобранные методом ретроспективной псевдорандомизации среди больных, проходивших лечение ранее. Разработан протокол из 5 последовательных упражнений дыхательной гимнастики. Пациентам основной группы (n = 73) к лечению в течение 10 дней добавлена исследуемая реабилитационная программа, затем оценивались результаты. Результаты. Получено достоверное различие продолжительности непрерывной кислородной поддержки между группами (5,1 ± 3,3 дня vs 8,0 ± 4,6 дня). При анализе в подгруппах важной самостоятельной ковариатой исхода оказалось наличие онкологического заболевания. Заключение. При использовании комплекса лечебной физической культуры в остром периоде течения НКИ повышается эффективность лечения за счет раннего снижения потребности в кислородной поддержке, ускоренной нормализации индекса оксигенации, повышения толерантности к физической нагрузке

In-situ SAXS study on the alignment of ordered systems of comb-shaped supramolecules:A shear-induced cylinder-to-cylinder transition

A tooth rheometer, designed to investigate in-situ the influence of large-amplitude oscillatory shear on the macroscopic orientation of complex fluids, is used to study the alignment of two supramolecular systems composed of a polyisoprene-block-poly(2-vinylpyi-idine) block copolymer with octyl gallate (OG) hydrogen bonded to the vinylpyridine block. The molecular ratio x between OG and pyridine groups in these two PI-b-P2VP(OG)(x) systems is 0.50 and 0.75, respectively. In both cases, a hexagonally ordered cylindrical self-assembly was revealed by small-angle X-ray scattering in a broad temperature range. The spacing of the hexagonal structure decreases significantly on heating and reversibly increases on cooling. In in-situ SAXS experiments, performed with the tooth rheometer, a gradual macroscopic alignment of the nanoscale structure is observed on heating for both supramolecular systems. The most striking feature is a shear-induced transition from one hexagonal structure to another, more aligned, hexagonal structure observed for PI-b-P2VP(OG)0.75 in the temperature range 120-140degreesC. The transition is accompanied by an abrupt reduction of the domain spacing and additionally by a decrease of the phase angle measured by the rheometer. In the PI-b-P2V-P(OG)(0.5) system a comparable reduction in the spacing is observed at 90-95degreesC. In this case, it coincides with the most intensive macroscopic alignment of the sample, proceeding in a continuous rather than discontinuous fashion. This behavior is discussed in terms of the breaking of the hydrogen bonds between OG and P2VP being facilitated by shear

Self-Assembly of Supramolecular Triblock Copolymer Complexes

Four different poly(tert-butoxystyrene)-b-polystyrene-b-poly(4-vinylpyridine) (PtBOS-b-PS-b-P4VP) linear triblock copolymers, with the P4VP weight fraction varying from 0.08 to 0.39, were synthesized via sequential anionic polymerization. The values of the unknown interaction parameters between styrene and tert-butoxystyrene and between tert-butoxystyrene and 4-vinylpyridine were determined from random copolymer blend miscibility studies and found to satisfy 0.031<χS,tBOS<0.034 and 0.39<χ4VP,tBOS<0.43, the latter being slightly larger than the known 0.30<χS,4VP≤0.35 value range. All triblock copolymers synthesized adopted a P4VP/PS core/shell cylindrical self-assembled morphology. From these four triblock copolymers supramolecular complexes were prepared by hydrogen bonding a stoichiometric amount of pentadecylphenol (PDP) to the P4VP blocks. Three of these complexes formed a triple lamellar ordered state with additional short length scale ordering inside the P4VP(PDP) layers. The self-assembled state of the supramolecular complex based on the triblock copolymer with the largest fraction of P4VP consisted of alternating layers of PtBOS and P4VP(PDP) layers with PS cylinders inside the latter layers. The difference in morphology between the triblock copolymers and the supramolecular complexes is due to two effects: (i) a change in effective composition and, (ii) a reduction in interfacial tension between the PS and P4VP containing domains. The small angle X-ray scattering patterns of the supramolecules systems are very temperature sensitive. A striking feature is the disappearance of the first order scattering peak of the triple lamellar state in certain temperature intervals, while the higher order peaks (including the third order) remain. This is argued to be due to the thermal sensitivity of the hydrogen bonding and thus directly related to the very nature of these systems.