Time-domain Brillouin Scattering as a Local Temperature Probe in Liquids

We present results of time-domain Brillouin scattering (TDBS) to determine the local temperature of liquids in contact to an optical transducer. TDBS is based on an ultrafast pump-probe technique to determine the light scattering frequency shift caused by the propagation of coherent acoustic waves in a sample. Since the temperature influences the Brillouin scattering frequency shift, the TDBS signal probes the local temperature of the liquid. Results for the extracted Brillouin scattering frequencies recorded at different liquid temperatures and at different laser powers - i.e. different steady state background temperatures- are shown to demonstrate the usefulness of TDBS as a temperature probe. This TDBS experimental scheme is a first step towards the investigation of ultrathin liquids measured by GHz ultrasonic probing.Comment: arXiv admin note: substantial text overlap with arXiv:1702.0107

Development of effective anti-inflammatory drug candidates among novel thiazolopyridines

In an effort to develop novel anti-inflammatory agents, a series of thiazolo[4,5-b]pyridines were synthesized and modified at the N3 position. The structures of the obtained compounds were confirmed by 1H NMR spectroscopy and elemental analysis. The synthesized substances were preselected via molecular docking­ to be tested for their anti-inflammatory activity in vitro. Evaluation of compounds using the carrageenan-induced rat paw edema method showed strong anti-inflammatory action of some compounds (1, 2, 8) which exceeded that of ibuprofen

Optical precursors in transparent media

We theoretically study the linear propagation of a stepwise pulse through a dilute dispersive medium when the frequency of the optical carrier coincides with the center of a natural or electromagnetically induced transparency window of the medium (slow-light systems). We obtain fully analytical expressions of the entirety of the step response and show that, for parameters representative of real experiments, Sommerfeld-Brillouin precursors, main field and second precursors "postcursors" can be distinctly observed, all with amplitudes comparable to that of the incident step. This behavior strongly contrasts with that of the systems generally considered up to now

СИНТЕЗ ТА ПРОТИЗАПАЛЬНІ ВЛАСТИВОСТІ ДЕЯКИХ С5 ЗАМІЩЕНИХ 3-МЕТИЛ-4-ТІОКСО-ТІАЗОЛІДИН-2-ОНІВ

Introduction. The study of the reactivity of 4-thiazolidone derivatives and the implementation of their chemical transformations is a promising area for the search for new biologically active substances. This is due to the wide range of biological activity of this class of compounds, as well as the presence of a number of reactive centers, which allows for various modifications of the original structure. Taking into account these circumstances, the synthesis of new substances as potential drug-like molecules among this class of compounds is relevant. The aim of the study – to synthesize some C5 substituted derivatives of 3-methyl-4-thioxo-thiazolidin-2-one for pharmacological screening in vivo of their anti-inflammatory activity. Research Methods. Organic synthesis, 1H NMR spectroscopy, elemental analysis, pharmacological screening were performed. Results and Discussion. The synthetic part of the work consisted in the structural modification of 3-methyl-4-thioxo-thiazolidin-2-one. The active methylene group at the C5 position of the said scafold exhibits CH-acidic properties and allows to carry out the azo coupling reaction with aryldiazonium salts to give the corresponding 3-methyl-5-(aryl-hydrazones)-4-thioxo-thiazolidin-2-ones. The structure of the obtained compounds and the interpretation of the performed chemical studies were confirmed by the data of elemental analysis and 1H NMR spectroscopy. The study of the effect of synthesized substances on the course of the exudative phase of inflammation was performed on the basis of the carrageenan model of inflammatory edema of the paws of white rats. The presence of an inflammatory reaction was established with a change in the volume of the limb by the oncometric method at the beginning of the experiment and 4 hours after the introduction of the phlogogenic agent. For comparison, the anti-inflammatory effect of Ibuprofen was studied under similar conditions. The synthesized compounds have anti-inflammatory properties, and some of them in terms of activity are close to or exceed the comparison drug. Conclusions. As a result of structural modification of 3-methyl-4-thioxo-thiazolidin-2-one at position C5, a series of novel 3-methyl-5-(aryl-hydrazone)-4-thioxo-thiazolidin-2-ones was synthesized. The studies carried out on the anti-inflammatory activity of the synthesized compounds demonstrate the potential to search for anti-inflammatory agents among this class of compounds. We are continuing to study the reactivity and chemical transformations with the prospect of studying the biological activity of this class of compounds.Вступление. Изучение реакционной способности производных 4-тиазолидона и осуществление их химических превращений является перспективным направлением поиска новых биологически активных веществ. Это обусловлено широким спектром биологической активности указанного класса соединений, а также наличием ряда реакционно способных центров, позволяющих проводить разностороннюю модификацию исходной структуры. Принимая во внимание данные обстоятельства, актуальным является синтез новых веществ как потенциальных биомолекул среди указанного класса соединений. Цель исследования – провести синтез некоторых C5 замещенных производных 3-метил-4-тиоксо-тиазолидин-2-она для фармакологического скрининга in vivo их противовоспалительной активности. Методы исследования. Проведено органический синтез, 1Н ЯМР-спектроскопию, элементный анализ, фармакологический скрининг. Результаты и обсуждение. Синтетическая часть работы заключалась в структурной модификации 3-метил-4-тиоксо-тиазолидин-2-она. Активная метиленовая группа в положении C5 указанного скафолда проявляла СН-кислотные свойства и позволила апробировать ее в реакции азосочетания с солями арилдиазония с получением соответствующих 3-метил-5-(арил-гидразоно)-4-тиоксо-тиазолидин-2-онов. Строение полученных соединений и интерпретация проведенных химических исследований подтверждены данными элементного анализа и 1Н ЯМР-спектроскопии. Влияние синтезированных веществ на протекание экссудативной фазы воспаления изучали на основе карагениновой модели воспалительного отека лап белых крыс. Наличие воспалительной реакции устанавливали по изменению объема конечности онкометричным методом в начале опыта и через 4 ч после введения флогогенного агента. Для сравнения в аналогичных условиях изучали противовоспалительный эффект известного противовоспалительного лекарственного средства – ибупрофена. Полученные результаты фармакологического скрининга показали, что синтезированные соединения обладают противовоспалительными свойствами, а некоторые из них по показателям активности приближаются к или превышают препарат ­сравнения. Выводы. В результате структурной модификации 3-метил-4-тиоксо-тиазолидин-2-она по положению C5 синтезировано серию новых 3-метил-5-(арил-гидразоно)-4-тиоксо-тиазолидин-2-онов. Проведенные исследования противовоспалительной активности синтезированных соединений демонстрируют потенциал поиска противовоспалительных агентов среди указанного класса соединений. Мы продол­жаем исследовать реакционную способность, а также химические превращения с перспективой изучения биологической активности этого класса соединений.Вступ. Вивчення реакційної здатності похідних 4-тіазолідону та здійснення їх хімічних перетворень є перспективним напрямком пошуку нових біологічно активних речовин. Це зумовлено широким спектром біологічної активності вказаного класу сполук, а також наявністю ряду реакційно здатних центрів, що дає змогу проводити різносторонню модифікацію вихідної структури. З огляду на дані обставини, актуальним є синтез нових речовин як потенційних біомолекул серед вказаного класу сполук. Мета дослідження – провести синтез деяких C5 заміщених похідних 3-метил-4-тіоксо-тіазолідин-2-ону для фармакологічного скринінгу in vivo їх протизапальної активності. Методи дослідження. Проведено органічний синтез, 1Н ЯМР-спектроскопію, елементний аналіз, фармакологічний скринінг. Результати й обговорення. Синтетична частина роботи полягала у структурній модифікації 3-метил-4-тіоксо-тіазолідин-2-ону. Активна метиленова група в положенні C5 зазначеного скафолду проявляла СН-кислотні властивості та дозволила апробувати її в реакції азосполучення із солями арилдіазонію з отриманням відповідних 3-метил-5-(арил-гідразоно)-4-тіоксо-тіазолідин-2-онів. Будову одержаних сполук та інтерпретацію проведених хімічних досліджень підтверджено даними елементного аналізу та 1Н ЯМР-спектроскопії. Вплив синтезованих речовин на перебіг ексудативної фази запалення вивчали на основі карагенінової моделі запального набряку лап білих щурів. Наявність запальної реакції встановлювали за зміною об’єму кінцівки онкометричним методом на початку досліду і через 4 год після введення флогогенного агента. Для порівняння за аналогічних умов вивчали протизапальний ефект відомого протизапального лікарського засобу – ібупрофену. Отримані результати фармакологічного скринінгу показали, що синтезовані сполуки володіють протизапальними властивостями, а деякі з них за показниками активності наближаються до або перевищують препарат порівняння. Висновки. У результаті структурної модифікації 3-метил-4-тіоксо-тіазолідин-2-ону за положенням C5 синтезовано серію нових 3-метил-5-(арил-гідразоно)-4-тіоксо-тіазолідин-2-онів. Проведені дослідження протизапальної активності синтезованих сполук демонструють потенціал пошуку протизапальних агентів серед зазначеного класу сполук. Ми продовжуємо досліджувати реакційну здатність, а також хімічні перетворення з перспективою вивчення біологічної активності цього класу сполук

Interpolated wave functions for nonadiabatic simulations with the fixed-node quantum Monte Carlo method

Simulating nonadiabatic effects with many-body wave function approaches is an open field with many challenges. Recent interest has been driven by new algorithmic developments and improved theoretical understanding of properties unique to electron-ion wave functions. Fixed-node diffusion Monte Caro is one technique that has shown promising results for simulating electron-ion systems. In particular, we focus on the CH molecule for which previous results suggested a relatively significant contribution to the energy from nonadiabatic effects. We propose a new wave function ansatz for diatomic systems which involves interpolating the determinant coefficients calculated from configuration interaction methods. We find this to be an improvement beyond previous wave function forms that have been considered. The calculated nonadiabatic contribution to the energy in the CH molecule is reduced compared to our previous results, but still remains the largest among the molecules under consideration.Comment: 7 pages, 3 figure

Provision for Sanitary Epidemiological Welfare of the Population of the Jewish Autonomous Region during High Water and Post-Flooding Period

Put forward was operational protocol as regards Rospotrebnadzor institutions policies in the territory of the Jewish Autonomous Region for the prevention of epidemiological implications during the post-flooding period in reference to infectious diseases. Carried out were control measures over infection morbidity rate, drinking water quality, disinfection of water supply sources, as well as sewage systems. Actions undertaken made it possible to prevent cluster cases of infectious diseases both in the flooded areas and at the temporal accommodation sites; to provide control over acute intestinal and natural-focal disease incidence, keeping it to the level of long-term average annual indexes; and to supply the population with drinking water of high quality

Distinct Campylobacter fetus lineages adapted as livestock pathogens and human pathobionts in the intestinal microbiota

Campylobacter fetus is a venereal pathogen of cattle and sheep, and an opportunistic human pathogen. It is often assumed that C. fetus infection occurs in humans as a zoonosis through food chain transmission. Here we show that mammalian C. fetus consists of distinct evolutionary lineages, primarily associated with either human or bovine hosts. We use whole-genome phylogenetics on 182 strains from 17 countries to provide evidence that C. fetus may have originated in humans around 10,500 years ago and may have "jumped" into cattle during the livestock domestication period. We detect C. fetus genomes in 8% of healthy human fecal metagenomes, where the human-associated lineages are the dominant type (78%). Thus, our work suggests that C. fetus is an unappreciated human intestinal pathobiont likely spread by human to human transmission. This genome-based evolutionary framework will facilitate C. fetus epidemiology research and the development of improved molecular diagnostics and prevention schemes for this neglected pathoge

Investigation of the Enteric Pathogenic Potential of Oral Campylobacter concisus Strains Isolated from Patients with Inflammatory Bowel Disease

BACKGROUND: Campylobacter concisus, a bacterium colonizing the human oral cavity, has been shown to be associated with inflammatory bowel disease (IBD). This study investigated if patients with IBD are colonized with specific oral C. concisus strains that have potential to cause enteric diseases. METHODOLOGY: Seventy oral and enteric C. concisus isolates obtained from eight patients with IBD and six controls were examined for housekeeping genes by multilocus sequence typing (MLST), Caco2 cell invasion by gentamicin-protection-assay, protein analysis by mass spectrometry and SDS-PAGE, and morphology by scanning electron microscopy. The whole genome sequenced C. concisus strain 13826 which was isolated from an individual with bloody diarrhea was included in MLST analysis. PRINCIPAL FINDINGS: MLST analysis showed that 87.5% of individuals whose C. concisus belonged to Cluster I had inflammatory enteric diseases (six IBD and one with bloody diarrhea), which was significantly higher than that in the remaining individuals (28.6%) (P<0.05). Enteric invasive C. concisus (EICC) oral strain was detected in 50% of patients with IBD and none of the controls. All EICC strains were in Cluster 1. The C. concisus strain colonizing intestinal tissues of patient No. 1 was closely related to the oral C. concisus strain from patient No. 6 and had gene recombination with the patient's own oral C. concisus. The oral and intestinal C. concisus strains of patient No. 3 were the same strain. Some individuals were colonized with multiple oral C. concisus strains that have undergone natural recombination. CONCLUSIONS: This study provides the first evidence that patients with IBD are colonized with specific oral C. concisus strains, with some being EICC strains. C. concisus colonizing intestinal tissues of patients with IBD at least in some instances results from an endogenous colonization of the patient's oral C. concisus and that C. concisus strains undergo natural recombination

Ionic liquids at electrified interfaces

Until recently, “room-temperature” (<100–150 °C) liquid-state electrochemistry was mostly electrochemistry of diluted electrolytes(1)–(4) where dissolved salt ions were surrounded by a considerable amount of solvent molecules. Highly concentrated liquid electrolytes were mostly considered in the narrow (albeit important) niche of high-temperature electrochemistry of molten inorganic salts(5-9) and in the even narrower niche of “first-generation” room temperature ionic liquids, RTILs (such as chloro-aluminates and alkylammonium nitrates).(10-14) The situation has changed dramatically in the 2000s after the discovery of new moisture- and temperature-stable RTILs.(15, 16) These days, the “later generation” RTILs attracted wide attention within the electrochemical community.(17-31) Indeed, RTILs, as a class of compounds, possess a unique combination of properties (high charge density, electrochemical stability, low/negligible volatility, tunable polarity, etc.) that make them very attractive substances from fundamental and application points of view.(32-38) Most importantly, they can mix with each other in “cocktails” of one’s choice to acquire the desired properties (e.g., wider temperature range of the liquid phase(39, 40)) and can serve as almost “universal” solvents.(37, 41, 42) It is worth noting here one of the advantages of RTILs as compared to their high-temperature molten salt (HTMS)(43) “sister-systems”.(44) In RTILs the dissolved molecules are not imbedded in a harsh high temperature environment which could be destructive for many classes of fragile (organic) molecules