Optical transition radiation in fused quartz under external acoustic field

In the present paper we have investigated the optical transition radiation in a plate excited by a longitudinal acoustic wave. The spectral-angular density of the radiated energy is calculated. The numerical examples are given for a plate of fused quartz. These results show that the acoustic waves allow to control the parameters of the radiation. In particular, new resonance peaks appear in the spectral distribution of the radiation intensity. The height of the peaks can be tuned by choosing the parameters of the acoustic wave

Восстановление оттока желчи при повреждении гепатикохоледоха и несостоятельности билиобилиарного анастомоза после лапароскопической холецистэктомии

The aspect of injuring bile ducts during laparoscopic cholecystectomy is still of current concern. Causes of this complication include insufficient experience of surgical team, poor knowledge of topographic anatomy of subhepatic space, particularly when perivesical inflammatory infiltrate presents, inadequate approach conversion and so on. Most of patients with bile duct injuries undergo repeated operation in the same surgical unit where cholecystectomy was performed. In many cases, this results in a shortening of the segment of the common hepatic duct, which is favorable for restoration. Subsequent reconstructive surgery is usually performed in the worse conditions with a high risk of complications such as failure of sutures, biliary fistula, anastomotic stricture, etc. Most specialists recommend to abstain from primary reconstruction of the biliary tree in hospitals with no proper experience in hepatobiliary surgery and to perform only the external drainage of subhepatic space with subsequent admission of patient to a specialized clinic. We report a case of a young woman who suffered an excision of hepaticocholedochus fragment during laparoscopic cholecystectomy. A primary reconstructive surgery (hepatico-hepaticoanastomosis) was performed in the same clinic and resulted in external fistula of the common hepatic duct. The subsequent operation (hepaticoejunostomy) was performed in a specialized department of the regional clinical hospital. The woman underwent right-sided hypochondrium laparotomy with debridement of postoperative scar tissues. The stumps of common bile duct were mobilized in compact inflammatory infiltrate. The operation ended with distal stump closure and hepaticoenteroanastomosis formation. The patient was discharged with recovery. Six months later, her condition was satisfactory, and she was engaged in occupational activity.Проблема повреждений желчных протоков во время лапароскопической холецистэктомии не теряет свою актуальность. Причины осложнений: недостаточный опыт хирургической бригады, ограниченные знания топографической анатомии подпеченочного пространства, особенно в условиях перивезикального воспалительного инфильтрата, несвоевременная конверсия доступа и прочее.Большую часть больных с травмой желчных протоков повторно оперируют в хирургических отделениях, где выполняют холецистэктомию. Нередко это заканчивается несостоятельностью билиобилиарного анастомоза и приводит к укорочению перспективного для восстановления сегмента общего печеночного протока.Последующую реконструктивную операцию выполняют в худших условиях с высокой вероят­ностью различного рода осложнений (несостоятельность швов, желчный свищ, стриктура анастомоза и прочее). Большинство авторов рекомендуют воздержаться от первичных реконструкций билиарного дерева в стационарах без должного опыта гепатобилиарной хирургии и ограничиться санацией и наружным дренированием подпеченочного пространства с последующим направлением пациента в специализированные клиники. Представлено клиническое наблюдение лечения молодой женщины, которой во время лапароскопической холецистэктомии иссечен фрагмент гепатикохоледоха.В этой же клинике выполнена первичная реконструктивная операция (гепатикогепатикоанастомоз), после которой сформировался наружный свищ общего печеночного протока. Очередная операция проведена в специализированном отделении областной клинической больницы. Выполнена комбинированная правосторонняя подреберная лапаротомия с иссечением после­операционного рубца. В плотном воспалительном инфильтрате с напластованием фибрина мобилизованы культи общего печеночного протока. Дистальная культя ушита. Сформирован гепатикоэнтероанастомоз. Пациентка выписана с выздоровлением. При осмотре через 6 месяцев состояние удовлетворительное, работает по специальности

Experimental investigation of optical transition radiation in amorphous quartz

Optical transition radiation (OTR) in amorphous quartz is investigated experimentally for electrons with energies 7.5MeV. It is shown that the Cherenkov radiation and OTR can be separated at specific conditions. The linear polarization of OTR is investigated and it is shown that the polarization is radial. The results of measurements for the spectral distribution of OTR have shown the maximum intensity of radiation at the wavelengths in the range 320–500 nm

ADAPT study: adaptation of evidence-informed complex population health interventions for implementation and/or re-evaluation in new contexts: protocol for a Delphi consensus exercise to develop guidance

Introduction Complex population health interventions that are effective in one context may not be effective elsewhere, and may even be harmful. As such, an intervention may require adaptation to ensure it fits with a new context. To date, there is no overarching guidance to help researchers to adapt and evaluate interventions in new contexts, and no criteria to support research funders or journals assess proposed or reported adaptations or evaluation. There is limited assistance for policy-makers and practitioners to decide if evidence-informed interventions are appropriate to their context, or if adaptation and further evaluation is needed. This Delphi exercise will contribute to the development of guidance for these communities to support the adaptation, implementation and/or re-evaluation of complex population health interventions in new contexts. Methods We will conduct a Delphi consensus exercise to gather expert opinion from researchers, research funders, journal editors and policy-makers. Expert opinion will be sought on: appropriate definitions and concepts, identifying key methodological considerations and establishing adaptations and processes to be undertaken during adaptation of complex population health interventions in new contexts. Ethics and dissemination Ethics approval for the Delphi exercise has been obtained from the University of Glasgow and and the RAND institutional research board. Dissemination of the results of this study will be through peer-reviewed publications, workshops at national and international conferences, and a summary of the guidance developed for key organisations and stakeholders

Influence of temperature gradient on diffracted X-ray spectrum in quartz crystal

In this work characteristics of hard X-ray (with energy higher than 30 keV) were investigated. In the experiment we measured spectra of X-ray reflected by a quartz monocrystal in Laue geometry under influence of the temperature gradient. The measurements were made by the spectrometer BDER-KI-11K with 300 eV resolution on the 17.74 keV spectral line of Am241 and the spectrometer XR-100CR with 270 eV resolution on the same spectral line. An existence of temperature gradient leads to increasing of the diffracted beam intensity. The intensity was measured dependently on the temperature of one of the edge of the crystal

Influence of temperature gradient on diffracted X-ray spectrum in quartz crystal

In this work characteristics of hard X-ray (with energy higher than 30 keV) were investigated. In the experiment we measured spectra of X-ray reflected by a quartz monocrystal in Laue geometry under influence of the temperature gradient. The measurements were made by the spectrometer BDER-KI-11K with 300 eV resolution on the 17.74 keV spectral line of Am241 and the spectrometer XR-100CR with 270 eV resolution on the same spectral line. An existence of temperature gradient leads to increasing of the diffracted beam intensity. The intensity was measured dependently on the temperature of one of the edge of the crystal

Test of the CLAS12 RICH large scale prototype in the direct proximity focusing configuration

A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c up to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Laboratory. The adopted solution foresees a novel hybrid optics design based on aerogel radiator, composite mirrors and high-packed and high-segmented photon detectors. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). We report here the results of the tests of a large scale prototype of the RICH detector performed with the hadron beam of the CERN T9 experimental hall for the direct detection configuration. The tests demonstrated that the proposed design provides the required pion-to-kaon rejection factor of 1:500 in the whole momentum range.Comment: 15 pages, 23 figures, to appear on EPJ