Conventional superconductivity at 203 K at high pressures

A superconductor is a material that can conduct electricity with no resistance below its critical temperature (Tc). The highest Tc that has been achieved in cuprates1 is 133 K at ambient pressure2 and 164 K at high pressures3. As the nature of superconductivity in these materials has still not been explained, the prospects for a higher Tc are not clear. In contrast, the Bardeen-Cooper-Schrieffer (BCS) theory gives a guide for achieving high Tc and does not put bounds on Tc, all that is needed is a favorable combination of high frequency phonons, strong electron-phonon coupling, and a high density of states. These conditions can be fulfilled for metallic hydrogen and covalent compounds dominated by hydrogen4,5. Numerous calculations support this idea and predict Tc of 50-235 K for many hydrides6 but only moderate Tc=17 K has been observed experimentally7. Here we studied sulfur hydride8 where a Tc~80 K was predicted9. We found that it transforms to a metal at pressure ~90 GPa. With cooling superconductivity was found deduced from a sharp drop of the resistivity to zero and a decrease of Tc with magnetic field. The pronounce isotope shift of Tc in D2S is evidence of an electron-phonon mechanism of superconductivity that is consistent with the BCS scenario. The superconductivity has been confirmed by magnetic susceptibility measurements with Tc=203K. The high Tc superconductivity most likely is due to H3S which is formed from H2S under its decomposition under pressure. Even higher Tc, room temperature superconductivity, can be expected in other hydrogen-based materials since hydrogen atoms provide the high frequency phonon modes as well as the strong electron-phonon coupling

Experience in the implementation of palliative, combined and expanded operations in emergency surgery of gastric cancer

В статье рассмотрен опыт выполнения неотложных абдоминальных онкохирургических операций, выполненных на базе отделения абдоминальной онкологии за период 2012–2014 гг. Всего в исследование включен 51 больной, которым выполнены ургентные и срочные плановые операции по поводу осложнений рака желудка. Всего выполнено 27 паллиативных, 6 расширенных, 15 комбинированных операций. По-настоящему ургентных было только 2, во время которых были выполнены в обоих случаях гастрэктомии со спленэктомией без выполнения расширенных лимфодиссекций. Сделан вывод, что выполнение радикальных операций не увеличивает летальность при осложненном течении рака желудка. В мировой ургентной медицине используются различные классификации срочных, в т. ч. неотложных операций, наиболее унифицированной из которых является классификация WSES-2013. Традиционное, “отечественное” распределение неотложных онкологических операций на ургентные/срочные/плановые или даже чаще на ургентные/ плановые является устоявшимся и необходимым. Индивидуализация подхода к каждой ургентной операции, как и вообще тенденция к индивидуализации в онкологии, представляется неотъемлемым мотивом грядущих методологических перемен в неотложной онкохирургии.The article describes the experience of urgent oncosurgical abdominal operations carried out on the basis of Abdominal Oncology Department for the period 2012–2014 years. In total, the study included 51 patients, who underwent emergent and urgent elective surgery for complications of stomach cancer. Total holds 27 palliative, 6 advanced, 15 combined operations. The really emergent were only 2, during which were performed in both cases gastrectomy with splenectomy without performing extended lymph node dissection. It was concluded that the implementation of radical surgery does not increase mortality rate in complicated gastric cancer. In the world of emergent medicine there are used different classification approaches, including emergency operations, most of which is a unified classification WSES-2013. The traditional distribution of urgent cancer operations in urgent / emergency / routine or even more frequently in the urgent / routine is well established and necessary. Personalisation approach to each of urgent surgical case, as well as general trend towards individualization in oncology seems to be inherent motive of future methodological changes in emergency cancer surgery

колективна монографія

Кримінальний процесуальний кодекс 2012 року: ідеологія та практика правозастосування: колективна монографія / за заг. ред. Ю. П. Аленіна ; відпов. за вип. І. В. Гловюк. - Одеса : Видавничий дім «Гельветика», 2018. - 1148 с

Pyridinium bis(pyridine-jN)tetrakis(thiocyanato-cyanato-jN)ferrate(III)

In the title compound, (C5H6N)[Fe(NCS)4(C5H5N)2], the FeIII ion is coordinated by four thiocyanate N atoms and two pyridine N atoms in a trans arrangement, forming an FeN6 polyhedron with a slightly distorted octahedral geometry. Charge balance is achieved by one pyridinium cation bound to the complex anion via N—HS hydrogen bonding. The asymmetric unit consists of one FeIII cation, four thiocyanate anions, two coordinated pyridine molecules and one pyridinium cation. The structure exhibits – interactions between pyridine rings [centroid–centroid distances = 3.7267 (2), 3.7811 (2) and 3.8924 (2) A˚ ]. The N atom and a neighboring C atom of the pyridinium cation are statistically disordered with an occupancy ratio of 0.58 (2):0.42 (2).peerReviewe

The Condorcet paradox revisited

We analyze the Condorcet paradox within a strategic bargaining model with majority voting, exogenous recognition probabilities, and no discounting. Stationary subgame perfect equilibria (SSPE) exist whenever the geometric mean of the players' risk coefficients, ratios of utility differences between alternatives, is at most one. SSPEs ensure agreement within finite expected time. For generic parameter values, SSPEs are unique and exclude Condorcet cycles. In an SSPE, at least two players propose their best alternative and at most one player proposes his middle alternative with positive probability. Players never reject best alternatives, may reject middle alternatives with positive probability, and reject worst alternatives. Recognition probabilities represent bargaining power and drive expected delay. Irrespective of utilities, no delay occurs for suitable distributions of bargaining power, whereas expected delay goes to infinity in the limit where one player holds all bargaining power. Contrary to the case with unanimous approval, a player benefits from an increase in his risk aversion

High-Temperature Superconductivity in Hydrides: Experimental Evidence and Details

Since the discovery of superconductivity at ~ 200 K in H3S [1], similar or higher transition temperatures, Tcs, have been reported for various hydrogen-rich compounds under ultra-high pressures [2]. Superconductivity was experimentally proved by different methods, including electrical resistance, magnetic susceptibility, optical infrared, and nuclear resonant scattering measurements. The crystal structures of superconducting phases were determined by X-ray diffraction. Numerous electrical transport measurements demonstrate the typical behavior of a conventional phonon-mediated superconductor: zero resistance below Tc, shift of Tc to lower temperatures under external magnetic fields, and pronounced isotope effect. Remarkably, the results are in good agreement with the theoretical predictions, which describe superconductivity in hydrides within the framework of the conventional BCS theory. However, despite this acknowledgement, experimental evidences for the superconducting state in these compounds have recently been treated with criticism [3,4,5,6,7], which apparently stems from misunderstanding and misinterpretation of complicated experiments performed under very high pressures. Here, we describe in greater detail the experiments revealing high-temperature superconductivity in hydrides under high pressures. We show that the arguments against superconductivity [3,4,5,6,7] can be either refuted or explained. The experiments on the high-temperature superconductivity in hydrides clearly contradict the theory of hole superconductivity [8] and eliminate it [3].This article is published as Eremets, Mikhail I., Vasily S. Minkov, Alexander P. Drozdov, P. P. Kong, Vadim Ksenofontov, Sergii I. Shylin, Sergey L. Bud’ko et al. "High-temperature superconductivity in hydrides: experimental evidence and details." Journal of Superconductivity and Novel Magnetism 35, no. 4 (2022): 965-977. DOI: 10.1007/s10948-022-06148-1. Copyright 2022 The Author(s). Attribution 4.0 International (CC BY 4.0). Posted with permission. DOE Contract Number(s): AC02-07CH11358; AC02-07CH11358; SC0002613; 89233218CNA000001; DMR-1644779

High-Temperature Superconductivity in Hydrides : Experimental Evidence and Details

Since the discovery of superconductivity at ~ 200 K in H3S, similar or higher transition temperatures, Tcs, have been reported for various hydrogen-rich compounds under ultra-high pressures. Superconductivity was experimentally proved by different methods, including electrical resistance, magnetic susceptibility, optical infrared, and nuclear resonant scattering measurements. The crystal structures of superconducting phases were determined by X-ray diffraction. Numerous electrical transport measurements demonstrate the typical behavior of a conventional phonon-mediated superconductor: zero resistance below Tc, shift of Tc to lower temperatures under external magnetic fields, and pronounced isotope effect. Remarkably, the results are in good agreement with the theoretical predictions, which describe superconductivity in hydrides within the framework of the conventional BCS theory. However, despite this acknowledgement, experimental evidences for the superconducting state in these compounds have recently been treated with criticism, which apparently stems from misunderstanding and misinterpretation of complicated experiments performed under very high pressures. Here, we describe in greater detail the experiments revealing high-temperature superconductivity in hydrides under high pressures. We show that the arguments against superconductivity can be either refuted or explained. The experiments on the high-temperature superconductivity in hydrides clearly contradict the theory of hole superconductivity and eliminate it

Досвід виконання паліативних, комбінованих і розширених операцій у невідкладній хірургії раку шлунка

The article describes the experience of urgent oncosurgical abdominal operations carried out on the basis of Abdominal Oncology Department for the period 2012–2014 years. In total, the study included 51 patients, who underwent emergent and urgent elective surgery for complications of stomach cancer. Total holds 27 palliative, 6 advanced, 15 combined operations. The really emergent were only 2, during which were performed in both cases gastrectomy with splenectomy without performing extended lymph node dissection. It was concluded that the implementation of radical surgery does not increase mortality rate in complicated gastric cancer. In the world of emergent medicine there are used different classification approaches, including emergency operations, most of which is a unified classification WSES-2013. The traditional distribution of urgent cancer operations in  urgent / emergency / routine or even more frequently in the urgent / routine is well established and necessary. Personalisation approach to each of urgent surgical case, as well as general trend towards individualization in oncology seems to be inherent motive of future methodological changes in emergency cancer surgery.В статье рассмотрен опыт выполнения неотложных абдоминальных онкохирургических операций, выполненных на базе отделения абдоминальной онкологии за период 2012–2014 гг. Всего в исследование включен 51 больной, которым выполнены ургентные и срочные плановые операции по поводу осложнений рака желудка. Всего выполнено 27 паллиативных, 6 расширенных, 15 комбинированных операций. По-настоящему ургентных было только 2, во время которых были выполнены в обоих случаях гастрэктомии со спленэктомией без выполнения расширенных лимфодиссекций. Сделан вывод, что выполнение радикальных операций не увеличивает летальность при осложненном течении рака желудка. В мировой ургентной медицине используются различные классификации срочных, в т. ч. неотложных операций, наиболее унифицированной из которых является классификация WSES-2013. Традиционное, “отечественное” распределение неотложных онкологических операций на ургентные/срочные/плановые или даже чаще на ургентные/плановые является устоявшимся и необходимым. Индивидуализация подхода к каждой ургентной операции, как и вообще тенденция к индивидуализации в онкологии, представляется неотъемлемым мотивом грядущих методологических перемен в неотложной онкохирургии.У статті розглянуто досвід виконання невідкладних абдомінальних онкохірургічних операцій, виконаних на базі відділення абдомінальної онкології за період 2012-2014 рр. Всього в дослідження включений 51 хворий, яким виконані ургентні і термінові планові операції з приводу ускладнень раку шлунка. Всього виконано 27 паліативних, 6 розширених, 15 комбінованих операцій. По-справжньому ургентних було тільки 2, під час яких були виконані в обох випадках резекції шлунка з спленектомією без виконання розширених лімфодисекцій. Зроблено висновок, що виконання радикальних операцій не збільшує летальність при ускладненому перебігу раку шлунка. У світовій ургентній медицині використовуються різні класифікації термінових, в т. ч. невідкладних операцій, найбільш уніфікованої з яких є класифікація WSES-2013. Традиційний «вітчизняний» розподіл невідкладних онкологічних операцій на ургентні / термінові / планові або навіть частіше на ургентні / планові є усталеним і необхідним. Індивідуалізація підходу до кожної ургентної операції, як і взагалі тенденція до індивідуалізації в онкології, є невід'ємним мотивом прийдешніх методологічних змін в невідкладній онкохірургії