Lab Scale Fixed-Bed Reactor for Operando X-Ray Absorption Spectroscopy for Structure Activity Studies of Supported Metal Oxide Catalysts

Lab scale fixed-bed reactor is applied for operando transmission X-ray absorption spectroscopy (XAS) for structure-activity studies of supported metal oxide catalysts under real reaction conditions. This setup includes many properties of an optimal fixed-bed reactor for operando transmission XAS studies. For instance, it is usable in a wide range of temperature (up to 1,000°C), pressure and space velocity. Besides, this operando setup can be used for transmission XAS measurements in a wide edge energy range. The potential of this reactor for operando transmission XAS is demonstrated by, as examples, the three-way catalytic performance of Pd/Al2O3/CeZrO2 and Rh/Al2O

Multi-scale phase separation by explosive percolation with single-chromatin loop resolution.

The 2 m-long human DNA is tightly intertwined into the cell nucleus of the size of 10 μm. The DNA packing is explained by folding of chromatin fiber. This folding leads to the formation of such hierarchical structures as: chromosomal territories, compartments; densely-packed genomic regions known as Topologically Associating Domains (TADs), or Chromatin Contact Domains (CCDs), and loops. We propose models of dynamical human genome folding into hierarchical components in human lymphoblastoid, stem cell, and fibroblast cell lines. Our models are based on explosive percolation theory. The chromosomes are modeled as graphs where CTCF chromatin loops are represented as edges. The folding trajectory is simulated by gradually introducing loops to the graph following various edge addition strategies that are based on topological network properties, chromatin loop frequencies, compartmentalization, or epigenomic features. Finally, we propose the genome folding model - a biophysical pseudo-time process guided by a single scalar order parameter. The parameter is calculated by Linear Discriminant Analysis of chromatin features. We also include dynamics of loop formation by using Loop Extrusion Model (LEM) while adding them to the system. The chromatin phase separation, where fiber folds in 3D space into topological domains and compartments, is observed when the critical number of contacts is reached. We also observe that at least 80% of the loops are needed for chromatin fiber to condense in 3D space, and this is constant through various cell lines. Overall, ou

A Search for Possible Long Range Spin Dependent Interactions of the Neutron from Exotic Vector Boson Exchange

We present a search for possible spin dependent interactions of the neutron with matter through exchange of spin 1 bosons with axial vector couplings as envisioned in possible extensions of the Standard Model. This was sought using a slow neutron polarimeter that passed transversely polarized slow neutrons by unpolarized slabs of material arranged so that interactions would tilt the plane of polarization and develop a component along the neutron momentum. The result for the rotation angle, ϕ′=[2.8±4.6(stat.)±4.0(sys.)]×10−5 rad/m is consistent with zero. This result improves the upper bounds on the neutron-matter coupling g2A by about three orders of magnitude for force ranges in the mm– μm regime

Mixing Aβ(1-40) and Aβ(1-42) peptides generates unique amyloid fibrils

Recent structural studies show distinct morphologies for the fibrilsof Ab(1-42) and Ab(1-40), which are believed not to co-fibrillize.We describe here a novel, structurally-uniform 1 : 1 mixed fibrillarspecies, which differs from bothpure fibrils. It forms preferen-tially even when Ab(1-42) : Ab(1-40) peptides are mixed in a non-stoichiometric ratio

Эффективность вакцинации против COVID-19 в организованном коллективе: результаты проспективного исследования

   Objective: to assess the efficacy of COVID-19 vaccination against in organized group.   Materials and methods: A total of 122 adults, employees of a higher education institution participated in the study. Study participants were observed prospectively and filled out a questionnaire where they indicated their age, presence of chronic diseases, history of COVID-19 and vaccination status.   Findings: the study participants were divided into two groups: 59 vaccinated (48.36 %) and 63 unvaccinated (51.64 %) individuals with no differences in age between the groups. There were significantly fewer confirmed cases of COVID-19 in the vaccinated group (р = 0,0008457, df = 1; χ2 = 11,138), significant differences (p = 0.0084; df = 4; χ2 =13.678) were observed in the number of cases among study participants based on their vaccination status.   Conclusion: participants diagnosed with pneumonia were 75 % unvaccinated (p = 0,00729; df = 1; χ2 = 7,2). All hospitalized study participants were unvaccinated (p = 0,004678; χ2 =8,0). None of the vaccinated participants needed respiratory support (p = 0,0455; df = 1; χ2 = 4,0). Chronic disease in vaccinated subjects made a significant (p = 0,04563; df = 2; χ2 = 6,1743) impact on COVID-19 severity.   Цель: оценить эффективность вакцинации против COVID-19 в организованном коллективе.   Материалы и методы: в исследовании приняли участие 122 взрослых, сотрудников учреждения высшего образования. Участники исследования наблюдались проспективно, а также заполнили анкету, в которой указали возраст, наличие хронических заболеваний, анамнез по COVID-19 и статус вакцинации.   Результаты: участники исследования были разделены на две группы: 59 вакцинированных (48,36 %) и 63 невакцинированных (51,64 %) человека без различий в возрасте между группами. В группе вакцинированных было значительно меньше подтвержденных случаев COVID-19 (р = 0,0008457, df = 1; χ2 = 11,138), значительные различия (p = 0,0084; df = 4; χ2 = 13,678) наблюдались в количестве случаев заболевания среди участников исследования с учетом их статуса вакцинации.   Заключение: участники с диагнозом «Пневмония» в 75 % случаев были невакцинированными (p = 0,00729; df = 1; χ2 =7,2). Все госпитализированные участники исследования были не вакцинированы (p = 0,004678; χ2 =8,0). Ни один из вакцинированных участников не нуждался в респираторной поддержке (p = 0,0455; df = 1; χ2 = 4,0). Хронические заболевания у вакцинированных оказывали значимое (p = 0,04563; df = 2; χ2 = 6,1743) влияние на тяжесть COVID-19

Selective optogenetic stimulation of efferent fi bers in the vagus nerve of a large mammal

Background: Electrical stimulation applied to individual organs, peripheral nerves, or specific brain regions has been used to treat a range of medical conditions. In cardiovascular disease, autonomic dysfunction contributes to the disease progression and electrical stimulation of the vagus nerve has been pursued as a treatment for the purpose of restoring the autonomic balance. However, this approach lacks selectivity in activating function- and organ-specific vagal fibers and, despite promising results of many preclinical studies, has so far failed to translate into a clinical treatment of cardiovascular disease. Objective: Here we report a successful application of optogenetics for selective stimulation of vagal efferent activity in a large animal model (sheep). Methods and results: Twelve weeks after viral transduction of a subset of vagal motoneurons, strong axonal membrane expression of the excitatory light-sensitive ion channel ChIEF was achieved in the efferent projections innervating thoracic organs and reaching beyond the level of the diaphragm. Blue laser or LED light (>10 mW mm 2 ; 1 ms pulses) applied to the cervical vagus triggered precisely timed, strong bursts of efferent activity with evoked action potentials propagating at speeds of ~6 m s 1 . Conclusions: These findings demonstrate that in species with a large, multi-fascicled vagus nerve, it is possible to stimulate a specific sub-population of efferent fibers using light at a site remote from the vector delivery, marking an important step towards eventual clinical use of optogenetic technology for autonomic neuromodulation. © 2020 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/

Aging of the mammalian gastrointestinal tract: a complex organ system

Gastrointestinal disorders are a major cause of morbidity in the elderly population. The gastrointestinal tract is the most complex organ system; its diverse cells perform a range of functions essential to life, not only secretion, digestion, absorption and excretion, but also, very importantly, defence. The gastrointestinal tract acts not only as a barrier to harmful materials and pathogens but also contains the vast number of beneficial bacterial populations that make up the microbiota. Communication between the cells of the gastrointestinal tract and the central nervous and endocrine systems modifies behaviour; the organisms of the microbiota also contribute to this brain–gut–enteric microbiota axis. Age-related physiological changes in the gut are not only common, but also variable, and likely to be influenced by external factors as well as intrinsic aging of the cells involved. The cellular and molecular changes exhibited by the aging gut cells also vary. Aging intestinal smooth muscle cells exhibit a number of changes in the signalling pathways that regulate contraction. There is some evidence for age-associated degeneration of neurons and glia of the enteric nervous system, although enteric neuronal losses are likely not to be nearly as extensive as previously believed. Aging enteric neurons have been shown to exhibit a senescence-associated phenotype. Epithelial stem cells exhibit increased mitochondrial mutation in aging that affects their progeny in the mucosal epithelium. Changes to the microbiota and intestinal immune system during aging are likely to contribute to wider aging of the organism and are increasingly important areas of analysis. How changes of the different cell types of the gut during aging affect the numerous cellular interactions that are essential for normal gut functions will be important areas for future aging research

Оптические, механические и электрические характеристики теплового неохлаждаемого детектора болометрического типа на основе оксида ванадия

Determination of optical, mechanical and electrical characteristics is one of the decisive factors in the design of instrumentation structures of thermal uncooled bolometer-type detectors (microbolometers). The paper presents the results of optimization calculations by means of computer simulation of absorption, transmittance and reflection spectra of device structures of microbolometers based on thermosensitive vanadium oxide film by finite-difference time-domain method (FDTD). The characteristics of the investigated microbolometer structure were checked for compliance with mechanical and electrical requirements for this class of devices.Определение оптических, механических и электрических характеристик является одним из решающих факторов при проектировании приборных структур тепловых неохлаждаемых детекторов болометрического типа (микроболометров). В статье представлены результаты оптимизационных расчетов посредством компьютерного моделирования спектров поглощения, пропускания и отражения приборных структур микроболометров на основе термочувствительной пленки оксида ванадия методом конечных разностей во временной области (англ. finite-difference time-domain, FDTD). Выполнена проверка на соответствие характеристик исследуемой структуры микроболометра механическим и электрическим требованиям, предъявляемым к данному классу приборов

Расчет оптических параметров тонких пленок конструкционных материалов теплового неохлаждаемого детектора болометрического типа

The increased interest in utilizing uncooled thermal bolometer-type detectors (microbolometers) within the infrared or terahertz detection field is justified by their operational and technological characteristics, in particular: relatively low manufacturing cost, high detection efficiency, compatibility with silicon CMOS technology, and operation at room temperature. The performance of such detectors depends on optimizing critical parameters, which are dictated by both the geometrical design and the electrical, optical, and thermal properties of the materials used. The determination of optical parameters stands as a decisive factor in the design of microbolometer structures. This article delves into the examination of optical parameters of thin films of structural materials of microbolometer based on thermosensitive vanadium oxide film manufactured at JSC “INTEGRAL”. The investigation showcases the results of determining optical constants (refractive indexes n and absorption coefficients k) of thin films from the transmission curve by applying the reflection-transmission method. Furthermore, a comparison is carried out between the results of computer modeling of the transmission, reflection and absorption spectra – taking into account the obtained values of the coefficients n and k – and the empirical data from the in-situ experiment.Повышенный интерес к применению неохлаждаемых тепловых детекторов болометрического типа (микроболометров) в инфракрасном или терагерцовом поле обнаружения обоснован их эксплуатационными и технологическими характеристиками, в частности: относительно низкой стоимостью изготовления, высокой эффективностью обнаружения, совместимостью с кремниевой КМОП-технологией, работоспособностью при комнатной температуре. Характеристики таких детекторов зависят от оптимизации критических параметров, которые определяются геометрией конструкции, а также электрическими, оптическими и тепловыми свойствами применяемых материалов. Определение оптических параметров является одним из решающих факторов при проектировании приборных структур микроболометров. В статье исследованы оптические параметры тонких пленок конструкционных материалов микроболометра на основе термочувствительной пленки оксида ванадия, изготовленных в ОАО «ИНТЕГРАЛ». Приведены результаты определения посредством применения метода отражения-передачи оптических констант (коэффициентов преломления n и поглощения k) тонких пленок по кривой пропускания. Выполнено сравнение результатов компьютерного моделирования спектров пропускания, отражения и поглощения с учетом полученных значений коэффициентов n и k с данными натурного эксперимента