Defect formation and thermal stability of H in high dose H implanted ZnO

We studied the structural properties, defect formation, and thermal stability of H in hydrothermally grown ZnO single crystals implanted with H- dose ranging from 2.5×10¹⁶ to 1×10¹⁷ cm⁻². H implantation is found to create deformed layers with a uniaxial strain of 0.5–2.4% along the c-axis in ZnO, for the low and high dose, respectively. About 0.2–0.4% of the original implanted H concentration can still be detected in the samples by secondary ion mass spectrometry after annealing at a temperature up to 800 °C. The thermally stable H is tentatively attributed to H related defect complexes involving the substitutional H that are bound to O vacancies and/or the highly mobile interstitial H that are bound to substitutional Li occupying Zn vacancies as the samples are cooled slowly from high temperature annealing. H implantation to a dose of 1×10¹⁷ cm⁻² and followed by annealing at 800 °C, is found to result in the formation of vacancy clusters that evolved into faceted voids with diameter varying from 2 to 30 nm. The truncations around the voids form more favorably on the O-terminated surface than on the Zn-terminated surface, suggesting that O is a preferred surface polarity for the internal facets of the voids in the presence of H.Financial support from the Australian Research Council and the Norwegian Research Council (FRINATEK program) is acknowledged

Study of a novel type of the optical modes in VCSELs

We study novel side-emitting modes in VCSEL microcavities. These modes correspond to π-shaped propagation along the mesa diameter, reflection from angled mesa walls and bottom Bragg reflector. We believe this study of π-modes is important for optimization of VCSEL design for improvement of efficiency

Minority and mode conversion heating in (3He)-H JET plasma

Radio frequency (RF) heating experiments have recently been conducted in JET (He-3)-H plasmas. This type of plasmas will be used in ITER's non-activated operation phase. Whereas a companion paper in this same PPCF issue will discuss the RF heating scenario's at half the nominal magnetic field, this paper documents the heating performance in (He-3)-H plasmas at full field, with fundamental cyclotron heating of He-3 as the only possible ion heating scheme in view of the foreseen ITER antenna frequency bandwidth. Dominant electron heating with global heating efficiencies between 30% and 70% depending on the He-3 concentration were observed and mode conversion (MC) heating proved to be as efficient as He-3 minority heating. The unwanted presence of both He-4 and D in the discharges gave rise to 2 MC layers rather than a single one. This together with the fact that the location of the high-field side fast wave (FW) cutoff is a sensitive function of the parallel wave number and that one of the locations of the wave confluences critically depends on the He-3 concentration made the interpretation of the results, although more complex, very interesting: three regimes could be distinguished as a function of X[He-3]: (i) a regime at low concentration (X[He-3] < 1.8%) at which ion cyclotron resonance frequency (ICRF) heating is efficient, (ii) a regime at intermediate concentrations (1.8 < X[He-3] < 5%) in which the RF performance is degrading and ultimately becoming very poor, and finally (iii) a good heating regime at He-3 concentrations beyond 6%. In this latter regime, the heating efficiency did not critically depend on the actual concentration while at lower concentrations (X[He-3] < 4%) a bigger excursion in heating efficiency is observed and the estimates differ somewhat from shot to shot, also depending on whether local or global signals are chosen for the analysis. The different dynamics at the various concentrations can be traced back to the presence of 2 MC layers and their associated FW cutoffs residing inside the plasma at low He-3 concentration. One of these layers is approaching and crossing the low-field side plasma edge when 1.8 < X[He-3] < 5%. Adopting a minimization procedure to correlate the MC positions with the plasma composition reveals that the different behaviors observed are due to contamination of the plasma. Wave modeling not only supports this interpretation but also shows that moderate concentrations of D-like species significantly alter the overall wave behavior in He-3-H plasmas. Whereas numerical modeling yields quantitative information on the heating efficiency, analytical work gives a good description of the dominant underlying wave interaction physics

Роль эндоваскулярных и эндобилиарных методов в лечении осложнений после трансплантации печени

Liver transplantation is the treatment of choice for patients with end-stage liver disease or acute liver failure. However, vascular complications, such as hepatic artery stenosis and/or thrombosis, graft portal vein stenosis and biliodigestive strictures following liver transplantation are still common despite improvements and innovations in surgical techniques. These complications can lead to graft damage or even death, and they are  caused by many factors. Although minimally invasive interventional radiology is an optional treatment for such post-liver transplant complications, there is little research on this method of treatment.Трансплантация печени является признанным методом лечения пациентов с терминальной стадией заболеваний печени или острой печеночной недостаточностью. Однако сосудистые осложнения, такие как стеноз и/или тромбоз печеночной артерии, стеноз воротной вены трансплантата и билиодигестивные стриктуры, после трансплантации печени все еще часто встречаемы, несмотря на улучшения и инновации в хирургических методах. Данные осложнения могут приводить к повреждениям трансплантата или даже к летальному исходу. Этиология данных осложнений является многофакторной. Хотя малоинвазивная интервенционная радиология для лечения данных осложнений после трансплантации печени является опциональным вариантом лечения, существует достаточно малое количество проведенных исследований данного метода лечения

Лечение стриктур билиодигестивного анастомоза после трансплантации левого латерального сектора печени

Many studies have shown that biliary complications after transplantation of the left lateral segment (LLS) of the liver reduce graft and recipient survival. Thus, timely correction of biliary complications, and strictures in particular, improves long-term outcomes in transplantation. Objective: to analyze our own experience in correcting biliary strictures in LLS graft transplantation. Materials and methods. From February 2014 to April 2020, 425 LLS grafts were transplanted in children. 19 (4.5%) patients were diagnosed with biliary strictures at different times after transplantation (from 0.2 to 97 months). Results. Biliary strictures were more often formed a year after transplantation (17.8 ± 23.9 months). In 14 out of the 19 patients, internal-external biliary drainage was successfully performed with phased replacement of the catheter with one that was larger in diameter (from 8.5 Fr to 14 Fr). The catheters were removed in 8 patients after completion of the treatment cycle. Restenosis was not observed during follow-up (13 ± 8.7 months) after the internal-external biliary drainage catheter had been removed. In 5 cases, antegrade passage of a guide wire through the stricture was unsuccessful. As a result, biliary reconstruction was performed in 4 (21.1%) patients and retransplantation was required in 1 (5.3%) patient. Conclusion. An antegrade minimally invasive approach can successfully eliminate biliary strictures in most children after liver LLS graft transplantation. The proposed technique is effective and safe.Введение. Билиарные осложнения после трансплантации левого латерального сектора (ЛЛС) печени, согласно многим исследованиям, негативно влияют на выживаемость трансплантатов и реципиентов. Таким образом, своевременная коррекция билиарных осложнений, и в частности стриктур, позволяет улучшить отдаленные результаты трансплантации. Цель. Проанализировать собственный опыт лечения билиарных стриктур при трансплантации ЛЛС печени. Материалы и методы. С февраля 2014-го по апрель 2020 года проведено 425 трансплантаций ЛЛС печени детям. У 19 (4,5%) пациентов диагностированы стриктуры желчных протоков в разные сроки после трансплантации (от 0,2 до 97 мес.). Результаты. Билиарные стриктуры чаще формировались через год после трансплантации (17,8 ± 23,9 мес.). У 14 из 19 было успешно проведено наружно-внутреннее дренирование желчных протоков с этапной заменой дренажа на больший диаметр (с 8,5 до 14 Fr). Дренажи удалены у 8 пациентов после завершения цикла лечения. За период наблюдения (13 ± 8,7 мес.) после удаления дренажа рестенозов не отмечалось. В 5 случаях антеградное прохождение стриктуры не удалось, в связи с чем в 4 (21,1%) случаях выполнена билиарная реконструкция и в 1 (5,3%) случае потребовалась ретрансплантация. Выводы. Антеградный мини-инвазивный подход позволяет успешно устранить билиарные стриктуры у большинства детей после трансплантации ЛЛС печени. Предложенный алгоритм лечения является эффективным и безопасным

Eczema: tactics of choice external therapy

The therapeutic effects of synthetic tannins are based on their binding action, as well as on their anti-pruritic, antimicrobial and anti-inflammatory effects. Materials and methods. A clinical study of Neotanin spray, Neotanin lotion (suspension) and Neotanin cream was carried out in 8 clinical centres during the period from June, 2017 to January, 2018. The study had an open and non-comparative character. The study included 68 patients of both sex es aged from 1 month to 80 years suffering from eczema dermatosis in the acute weeping phase, including cases with complications after secondary infections (including eczema elements localized on the face). Before the study, information on the clinical history, demographic data, co-morbidities, physical examination data of the patients was collected. The treatment regimen included 2 stages: 1) Neotanin in the spray or lotion (suspension) form 3–4 times per day during 1–5 days, up to the full drying of eczema elements; 2) Neotanin in the cream form 3 times per day, up to the disappearance of the clinical manifestations of skin dermatosis. The duration of the study ranged from 5 to 14 days: the study was completed when a patient had achieved remission. The criteria for assessing the drug efficacy were as follows: dynamics of subjective complaints, objective assessment of the patient's condition (the presence and severity of clinical symptoms), dynamics of the Dermatology Life Quality Index (DLQI). Results. Neotanin preparations showed a high efficacy in the acute and subacute stages of the inflammatory process as an antipruritic agent. Itching stopped within 5 minutes after the drug application, with the antipruritic effect lasting for an average of 3–4 hours. In 85 % of the patients, marked excoriations were absent on the 3rd day of treatment. Neotanin demonstrated a pronounced anti-inflammatory effect. In 92 % of the patients, the symptoms of erythema and edema were significantly reduced one week after the beginning of treatment, with the manifestations of inflammatory exudation being conclusively decreased. One week following the beginning of treatment, 100 % of the patients demonstrated no oozing lesions. The absence of serious undesirable effects in the patients during the study evidences to the good tolerability and safety of this drug

Characterization of ion cyclotron resonance heating in presence of the ITER-like wall in JET

Carbon is not compatible with the long term use required for plasma facing components in future fusion reactors of the tokamak type e.g. from the point of view of erosion and tritium retention.Wand Be were chosen as plasma facing materials for ITER. JET was equipped with beryllium (as opposed to C or C-coated) walls in the shutdown of 2010-2011. To sustain the very high heat loads inevitably falling on it and thus excluding the use of metals with a low melting point such as Be and in spite of the fact that its radiation is significant because of its large Z, a Tungsten (W) orW-coated divertor was simultaneously installed. The recent JET campaign has focused on characterizing high density high temperature operation with this "ITER-like" wall (ILW). One of the questions that needed to be answered is whether the auxiliary heating methods do not lead to unacceptable high levels of impurity influx preventing fusion-relevant operation. This paper briefly reports on two aspects of the present understanding of ion cyclotron resonance heating (ICRH) or radio frequency (RF) heating in presence of the ILW: ICRH-specific impurity influx and heating performance. They are complementing related discussions on heat loads, and on plasmaWcontent and possible sources. A much more extensive study will be published elsewhere

Fernando SEBASTIÁN AGUILAR, Nueva Evangelización. Fe, cultura y política en la España de hoy, Ed. Encuentro, Madrid 1991, 302 pp. [RECENSIÓN]

\u3cp\u3eThe most recent JET campaign has focused on characterizing operation with the «ITER-like» wall. One of the questions that needed to be answered is whether the auxiliary heating methods do not lead to unacceptably high levels of impurity influx, preventing fusion-relevant operation. In view of its high single pass absorption, hydrogen minority fundamental cyclotron heating in a deuterium plasma was chosen as the reference wave heating scheme in the ion cyclotron domain of frequencies. The present paper discusses the plasma behavior as a function of the minority concentration X[H] in L-mode with up to 4MW of RF power. It was found that the tungsten concentration decreases by a factor of 4 when the minority concentration is increased from X[H] ≈ 5% to X[H] % 20% and that it remains at a similar level when X[H] is further increased to 30%; a monotonic decrease in Beryllium emission is simultaneously observed. The radiated power drops by a factor of 2 and reaches a minimum at X[H] ≈ 20%. It is discussed that poor single pass absorption at too high minority concentrations ultimately tailors the avoidance of the RF induced impurity influx. The edge density being different for different minority concentrations, it is argued that the impact ICRH has on the fate of heavy ions is not only a result of core (wave and transport) physics but also of edge dynamics and fueling.\u3c/p\u3

Исследование качества жизни родственных доноров фрагмента печени в отдаленном послеоперационном периоде

Introduction. Quality of life (QoL) is a new promising area of clinical medicine that provides the opportunity to assess the state of health of the patient and to have a notion of the surgery effects based on the parameters which are lying at the intersection of scientific approach of the surgeons and subjective point of view of the patient.Materials and methods. The study included 52 living-related liver fragment donors operated between 2009 and 2014. Donors were surveyed after 2–5 years from the surgery. Comparison group was formed by healthy volunteers, students of the Medical University. The Russian version of the non-specific SF-36 questionnaire was used to assess QoL.Results. Donors in the postoperative period have demonstrated a high level of physical parameter (57.65 ± 3.8). Parameter of psychological health in the postoperative period was (52.01 ± 5.2). These figures are comparable with the results in the comparison group (p &gt; 0.05). All donors have returned to normal life.Conclusions. Overall results of this study were similar to those of the foreign colleagues which confirm the high safety of liver resection surgery and the efficacy of SF-36 questionnaire in the assessment of quality of life of the living-related liver fragment donors.Введение. Оценка качества жизни (КЖ) – новое перспективное направление клинической медицины, предоставляющее возможность оценить состояние здоровья пациента и составить представление о последствиях оперативного вмешательства по параметрам, которые находятся на стыке научного подхода хирургов и субъективной точки зрения пациента.Материалы и методы. В исследование были включены 52 родственных донора фрагмента печени, оперированных в период с 2009-го по 2014 год. Доноры опрашивались спустя 2–5 лет после оперативного вмешательства. В качестве группы сравнения выступили здоровые добровольцы – студенты медицинского университета. Для оценки качества жизни применялась русскоязычная версия неспецифического опросника SF-36.Результаты. Доноры в послеоперационном периоде продемонстрировали высокий уровень физического параметра (57,65 ± 3,8). Психологический параметр здоровья в послеоперационном периоде составил 52,01 ± 5,2. Данные показатели сопоставимы с результатами в группе сравнения (р &gt; 0,05). Все доноры вернулись к нормальной жизнедеятельности.Выводы. Результаты настоящего исследования схожи с данными зарубежных коллег, что подтверждает безопасность операции эксплантации фрагментов печени и эффективность опросника SF-36 в оценке качества жизни родственных доноров фрагмента печени