About proof-search in intuitionistic natural deduction calculus using partial Skolemization

In this paper, automated proof search in single-conclusion sequential variant of intuitionistic and minimal predicate calculus is considered. In this algorithm, meta-variables and partial Skolemization are used. Theorems of soundness and completeness for the considered algorithm are proved. © Published under licence by IOP Publishing Ltd

Рентгенохирургия ятрогенного повреждения желчных протоков после лапароскопической холецистэктомии (опыт одного центра)

IM OF STUDY To show the possibilities of antegrade X-ray surgical techniques in the treatment of iatrogenic bile duct injuries after videolaparoscopic cholecystectomy.MATERIAL AND METHODS The study included 24 patients with “minor” and 20 patients with “major” (according to Strasberg) iatrogenic injuries of the extrahepatic biliary tract. Antegrade endobiliary intervention was performed in 26 patients, including the “bridge-procedure” variant preceding the reconstructive surgery. Endobiliary drains were maintained during the reconstructive surgery and in the early postoperative period to control the viability of the anastomosis.When a stricture of the biliodigestive anastomosis (BDA) was detected, balloon dilatation of the anastomotic area was performed. In the subgroup of “minor” injuries, external drainage of the subhepatic biloma in 18 people were supplemented with endoscopic papillotomy in 12 cases.RESULTS In all patients with “minor” injuries of the biliary tree, X-ray surgical techniques were effective. In 11 patients with “major” bile duct injuries, cholangiostomy drainage was gradually transformed into external-internal drainage. In 2 trauma cases of classes D and E temporary antegrade stenting of the duct injury area with a coated self-expanding endobiliary stent was performed. The follow-up period after removal of the antegrade frame drainage ranged from 8 months to 14 years. There were no stricture or failure of BDA.CONCLUSION Short-term external biliary drainage, including the use of rendezvous techniques, may be suffi cient to eliminate the failure of the cystic duct stump. Cholangiostomy drainage, temporary endobiliary stent allow preparing the patient for reconstructive intervention. Drainage marking of the damaged area facilitates the verifi cation of tubular structures in the reconstruction area. Preservation of drainage after reconstructive intervention is the prevention of failure of the biliodigestive anastomosis in the early postoperative period, the development of its stricture in the long term.ЦЕЛЬ Показать возможности антеградных рентгенхирургических методик в лечении ятрогенных по­вреждений желчных протоков после видеолапароскопической холецистэктомии.МАТЕРИАЛ И МЕТОДЫ В исследование включены 24 пациента с «малыми» и 20 пациентов с «большими» (по Strasberg) ятрогенными повреждениями внепеченочных желчных путей. Антеградное эндобилиарное вмешательство было выполнено 26 пациентам, в том числе в варианте “bridge-procedure”, предшествовавшем реконструктивной операции. Эндобилиарные дренажи сохранялись во время рекон­структивной операции и в раннем послеоперационном периоде для контроля состоятельности анастомоза. При выявлении стриктуры билиодигестивного анастомоза (БДА) выполняли баллонную дилатацию зоны анастомоза. В подгруппе «малых» повреждений наружное дренирование подпеченочной биломы у 18 человек было дополнено эндоскопической папиллотомией в 12 наблюдениях.РЕЗУЛЬТАТЫ У всех пациентов с «малыми» повреждениями желчного дерева рентгенохирургические методики оказались эффективными. У 11 пациентов с «большими» повреждениями желчных протоков холангиостомический дренаж этапно был трансформирован в наружно-внутренний. В 2 наблюдениях при травме классы D и Е использовали временное антеградное стентирование зоны повреждения протоков покрытым саморасширяющимся эндобилиарным стентом. Сроки наблюдения после удаления антеградного каркасного дренажа составили от 8 месяцев до 14 лет. Стриктуры и несостоятельности БДА отмечено не было.ЗАКЛЮЧЕНИЕ Кратковременное наружное билиарное дренирование, в том числе с применением «рандеву методик», может оказаться достаточным для устранения несостоятельности культи пузырного протока. Холангиостомический дренаж, временный эндобилиарный стент позволяют подготовить пациента к реконструктивному вмешательству. Дренажная маркировка зоны повреждения облегчает верификацию трубчатых структур в области реконструкции. Сохранение дренажа после реконструктивного вмешательства является профилактикой несостоятельности билиодигестивного анастомоза в раннем послеоперационном периоде, развития его стриктуры в отдаленные сроки

Modern Russian Labor Market and Disabled: Analysis of Statistical Data

The article, using the statistics of Federal state statistics service, Pension Fund and research Agency “HeadHunter”, shows the difficult situation in the labor market with the employment of people with disabilities of working age.В статье на основе статистических данных Росстата, Пенсионного фонда и исследования агентства HeadHunter показывается непростая ситуация на рынке труда с трудоустройством инвалидов трудоспособного возраста

Vortex shedding behind an obstacle in a channel under transition to turbulence in steady and pulsating flows

© Published under licence by IOP Publishing Ltd. Experimental research and DNS of separated flow over a spanwise semicylindrical rib mounted in a rectangular channel have been performed for the cases of steady and pulsating flow with transition to turbulence. Spiral motion of fluid behind the rib directed from the channel walls towards the channel symmetry plane has been shown to govern the formation of large vortices in the mixing layer starting from some critical Reynolds number. The mechanism of origination of such motion has been hypothesized. The effect of frequency and amplitude of forced freestream pulsations on the vortex pattern behind the rib has been described

Temperature-stable operation of a quantum dot semiconductor disk laser

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 93, 051104 (2008) and may be found at https://doi.org/10.1063/1.2968137.We demonstrate temperature-independent output characteristics of an optically pumped semiconductor disk laser (SDL) based on quantum dots (QDs) grown in the Stranski-Krastanow regime. The gain structure consists of a stack of 7×3 QD layers, each threefold group being located at an optical antinode position. The SDL emits at 1210nm independent of the pump power density. Threshold and differential efficiency do not dependent on heat sink temperature. Continuous-wave operation close to 300mW output power is achieved using the ground-state transition of the InGaAs QDs.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP6/016769/EU/Nano-Photonics Materials and Technologies for Multicolor High-Power Sources/NATA

Vertical-external-cavity surface-emitting lasers and quantum dot lasers

The use of cavity to manipulate photon emission of quantum dots (QDs) has been opening unprecedented opportunities for realizing quantum functional nanophotonic devices and also quantum information devices. In particular, in the field of semiconductor lasers, QDs were introduced as a superior alternative to quantum wells to suppress the temperature dependence of the threshold current in vertical-external-cavity surface-emitting lasers (VECSELs). In this work, a review of properties and development of semiconductor VECSEL devices and QD laser devices is given. Based on the features of VECSEL devices, the main emphasis is put on the recent development of technological approach on semiconductor QD VECSELs. Then, from the viewpoint of both single QD nanolaser and cavity quantum electrodynamics (QED), a single-QD-cavity system resulting from the strong coupling of QD cavity is presented. A difference of this review from the other existing works on semiconductor VECSEL devices is that we will cover both the fundamental aspects and technological approaches of QD VECSEL devices. And lastly, the presented review here has provided a deep insight into useful guideline for the development of QD VECSEL technology and future quantum functional nanophotonic devices and monolithic photonic integrated circuits (MPhICs).Comment: 21 pages, 4 figures. arXiv admin note: text overlap with arXiv:0904.369

Ni+-irradiated InGaAs/GaAs quantum wells: picosecond carrier dynamics

Room-temperature carrier dynamics as functions of heavy-ion implantation and subsequent thermal annealing were investigated for technologically important InGaAs/GaAs quantum wells (QWs) by means of a time-resolved up-conversion method. Sub-picosecond lifetimes were achieved at 10 MeV Ni+ doses of (20-50) x 1010 ions cm-2. The decay rates reached a maximum at the highest irradiation dose, yielding the shortest lifetime of the confined QW states of 600 fs. A simple theoretical model is proposed for the photodynamics of the carriers. The relaxation rate depended on the irradiation dose according to a power law of 1.2, while the irradiated and subsequently annealed samples exhibited a power law of 0.35. The results are qualitatively interpreted.Room-temperature carrier dynamics as functions of heavy-ion implantation and subsequent thermal annealing were investigated for technologically important InGaAs/GaAs quantum wells (QWs) by means of a time-resolved up-conversion method. Sub-picosecond lifetimes were achieved at 10 MeV Ni+ doses of (20-50) x 1010 ions cm-2. The decay rates reached a maximum at the highest irradiation dose, yielding the shortest lifetime of the confined QW states of 600 fs. A simple theoretical model is proposed for the photodynamics of the carriers. The relaxation rate depended on the irradiation dose according to a power law of 1.2, while the irradiated and subsequently annealed samples exhibited a power law of 0.35. The results are qualitatively interpreted.Room-temperature carrier dynamics as functions of heavy-ion implantation and subsequent thermal annealing were investigated for technologically important InGaAs/GaAs quantum wells (QWs) by means of a time-resolved up-conversion method. Sub-picosecond lifetimes were achieved at 10 MeV Ni+ doses of (20-50) x 1010 ions cm-2. The decay rates reached a maximum at the highest irradiation dose, yielding the shortest lifetime of the confined QW states of 600 fs. A simple theoretical model is proposed for the photodynamics of the carriers. The relaxation rate depended on the irradiation dose according to a power law of 1.2, while the irradiated and subsequently annealed samples exhibited a power law of 0.35. The results are qualitatively interpreted.Peer reviewe