Variable Ultra-broadband and Narrowband Composite Polarization Retarders

We propose and experimentally demonstrate novel types of composite sequences of half-wave and quarter-wave polarization retarders, either permitting operation at ultra-broad spectral bandwidth or narrow bandwidth. The retarders are composed of stacked standard half-wave retarders and quarter-wave retarders of equal thickness. To our knowledge, these home-built devices outperform all commercially available compound retarders, made of several birefringent materials.Comment: 5 figures, 9 page

Диагностика и лечение травматических повреждений пищевода

Catedra chirurgie nr. 2, clinica 2, USMF „Nicolae Testemiţanu”Traumatic iatrogenic injuries and spontaneous ruptures of the esophagus are always serious, and are sometimes followed by pronounced and irreversible complications which include postoperative mortality rates of 30% in the first 24 hours and 60% after 24 hours. Perforation of the esophagus during esophagoscopy with fiber optic endoscopes was found in 0.007% of the observations, while the frequency of blind probing scar stricture of such damage increased by 15%.Травматические повреждения пищевода ятрогенного характера, как и спонтанный разрыв пищевода, считаются наиболее тяжелыми травмами. После таких травм наступают выраженные, иногда необратимые осложнения, с высокой послеоперационной летальностью, в первые 24 часа до 30%, а среди больных, оперированных позднее 24 часов после повреждения, показатель осложнений достигает 60%. Перфорация пищевода при эзофагоскопии эндоскопами на волоконной оптике встречается в 0,007% наблюдений, а при слепом бужировании его рубцовой стриктуры частота такого повреждения возрастает до 15%

Highly efficient broadband conversion of light polarization by composite retarders

Driving on an analogy with the technique of composite pulses in quantum physics, we propose highly efficient broadband polarization converters composed of sequences of ordinary retarders rotated at specific angles with respect to their fast-polarization axes.Comment: 5 pages, 3 figures; check JOSA A 201

Abdominal wall hernias after laparoscopic cholecystectomy

USMF ”N. Testemițanu”, Catedra chirurgie 2, Clinica chirurgie II, SCM ”Sfînta Treime”, Chișinău, Republica Moldova, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Scopul studiului: colecistectomia laparoscopică a fost rapid acceptată și dominată de un proses tehnic avansat ca alternativă a colecistectomiei clasice în tratamentul litiazei veziculare, însă până în prezent nu sunt definitiv studiate consecințele postoperatorii.Material și metode: Studiul se bazează pe o analiză a 502 bolnavi operați în clinică laparoscopic, dintre care pentru colecistită cronică calculoasă – 398, iar pentru colecistită acută calculoasă – 104. În 24 cazuri au fost depistate hernii poslaparoscopice, din care 8 pacienti au fost operați în diferite instituții medico-sanitare publice, iar în 4 cazuri au fost operați de urgență după hotarele țării. Femei au fost 480, bărbați – 22, cu vîrsta medie de 48,2 ani.Rezultate: Eventrații postoperatorii au fost la 24 pacienți. Mai frecvent herniile au avut loc în lotul de bolnavi operați în mod urgent pentru colecistită acută calculoasă – 18 cazuri, la cei cu colecistita cronică calculoasă eventrațiile au fost în 6 cazuri. La 8 bolnavi herniile au fost multiple (2), în regiunea epigastrală și ombilicală. Un rol important în dezvoltarea heniilor a avut starea peretelui abdominal, vîrsta, obezitatea, cînd situația intraoperatorie a impus lărgirea plăgii din cauza vezicii biliare cu pereții ingroșați și mărită, flegmonos schimbată, cât și prezența calculilor mari în ea și nesuturarea defectului aponeurotic. Hernioplastia s-a efectuat sub anestezie locală cu soluție 0,3% Lidocaină 60-80 ml cu țesuturi proprii în 20 cazuri, iar în 4 cazuri s-a efectuat sub anestezie generală oro-traheală cu plasă sintetică de propilen. În perioada postoperatorie precoce și tardivă complicații nu s-au înregistrat. Concluzii: Pentru prevenirea herniilor postoperatorii după colecistectomia laparoscopică este obligatoriu să se sutureze aponeuroza în toate cazurile după înlăturarea trocarelor cît și a vezicii biliare, ca metode de preîntîmpinare a herniilor peretelui abdominal.Aim: Laparoscopic cholecystectomy was quickly accepted and dominated by a technically advanced process as an alternative to conventional cholecystectomy in the treatment of gallbladder lithiasis, but so far the postoperative consequences have not been definitively studied. Material and methods: The study is based on an analysis of 502 patients that were operated using laparoscopic surgery, from them with chronic cholecystitis -398, and for acute calculus cholecystitis – 104. In 24 hernia cases were detected after laparoscopic operations, from which 8 patients were operated on in different public medical institutions, and in 4 cases patients were operated abroad. The study has 480 cases – women, men - 22, average age 48.2 years. Results: Postoperative eventrations occurred at 24 patients. More frequently hernias occurred in the group of patients that were operated urgently for acute calculus cholecystitis -18 cases, for those patients which had chronic calculus cholecystitis eventrations happened in 6 cases. 8 patients had multiple hernias(2), in epigastric and umbilical region. An important role in hernias development had the abdominal wall condition, age, obesity, when the intraoperative situation required a widening of the surgical wound due to enlarged gallbladder with thickened walls, with phlegmon changes, and the presence of large stones in it and no sutures of the aponeurotic defect. The plasty of hernia was performed under local anesthesia with 0.3 % Lidocaine solution 60-80 ml with own tissue in 20 cases, and in 4 cases was performed under general oro-tracheal anesthesia with propylene synthetic mesh. During the early and late postoperative periods, no complications were observed. Conclusions: To prevent postoperative hernia after laparoscopic cholecystectomy is mandatory in all cases to put aponeurotic sutures after removal of trocars as well as of gallbladder, as a method of preventing abdominal wall hernias

Broadband Faraday Isolator

Driving on an analogy with the technique of composite pulses in quantum physics, we propose a broadband Faraday rotator and thus a broadband optical isolator, which is composed of sequences of ordinary Faraday rotators and achromatic quarter-wave plates rotated at the predetermined angles.Comment: submitted to JOSA A, comments are welcom

Полиорганная недостаточность в хирургии

Department of Surgery N 2, State University of Medicine and Pharmacy "Nicolae Testemitanu"Multiple organ insufficiency syndromes complicate the postoperative evolution in urgent surgery in 10-28% of cases. In purulent complications of acute abdominal inflammatory diseases, its frequency can be up to 60%. Difficulties in appropriate diagnoses and treatment and high lethality, which can be up to 95%, determined the actuality of this study. The main cause of multiple organ insufficiency syndromes are infectious complications, particularly in inadequate management, which cause immune, metabolic, and homeostatic disturbances. Синдром полиорганной недостаточности осложняет течение послеоперационного периода в 10-28% случаев. При гнойных осложнениях острых воспалительных заболеваний органов брюшной полости, частота его достигает 60%. Трудность своевременной диагностики и лечения, высокая летальность, достигающая 95%, обусловили особую актуальность и сложность исследования этой проблемы. Основной причиной развития синдрома полиорганной недостаточности являются инфекционные осложнения, особенно при их несвоевременной диагностике или неадекватном лечении, вызывающие нарушения иммунного статуса больных, метаболизма, а также системы гомеостаза