Observation of asymmetric spectrum broadening induced by silver nanoparticles in a heavy-metal oxide glass

We demonstrate experimentally and support by a theoretical analysis an effect of asymmetric spectrum broadening, which results from doping of silver nanoparticles into a heavy-glass matrix, 90(0.5WO3-0.3SbPO4-0.2PbO)-10AgCl. The strong dispersion of the effective nonlinear coefficient of the composite significantly influences the spectral broadening via the self-phase modulation, and leads to a blue upshift of the spectrum. Further extension of the spectrum towards shorter wavelengths is suppressed by a growing loss caused by the plasmon resonance in the silver particles. The red-edge spectral broadening is dominated by the stimulated Raman Scattering.Comment: Accepted for publishing epl13477; EPL Journal 201

Optical control of electron spin coherence in CdTe/(Cd,Mg)Te quantum wells

Optical control of the spin coherence of quantum well electrons by short laser pulses with circular or linear polarization is studied experimentally and theoretically. For that purpose the coherent electron spin dynamics in a n-doped CdTe/(Cd,Mg)Te quantum well structure was measured by time-resolved pump-probe Kerr rotation, using resonant excitation of the negatively charged exciton (trion) state. The amplitude and phase shifts of the electron spin beat signal in an external magnetic field, that are induced by laser control pulses, depend on the pump-control delay and polarization of the control relative to the pump pulse. Additive and non-additive contributions to pump-induced signal due to the control are isolated experimentally. These contributions can be well described in the framework of a two-level model for the optical excitation of the resident electron to the trion.Comment: 15 pages, 18 figure

Effectiveness of pantoprazole for the treatment of erosive and ulcerative gastroduodenal lesions in patients taking dual antiplatelet therapy after emergency PCI

The effectiveness of proton pump inhibitors (PPIs) in patients with erosive and ulcerative lesions of the upper gastrointestinal tract (GIT), receiving dual antiplatelet therapy, is poorly evaluated. Aim. To determine the efficacy of PPIs in treatment of erosive and ulcerative lesions of stomach and duodenum in patients receiving dual antiplatelet therapy with aspirin and clopidogrel after urgent percutaneous coronary intervention (PCI) related to acute coronary syndromes (ACS). Methods. The study included 42 patients, whom urgent PCI related to ACS was performed. Duodenal and gastric erosive and ulcer lesions were found with gastroduodenoscopy in all of patients. Biopsy of antrum mucosae were evaluated to detect Helicobacter pilory (Hp). Repeated gastroduodenoscopy was provided through a month. Patients received dual antiplatelet therapy with aspirin and clopidogrel, and pantoprazole 40 mg per day for prevention of erosive-ulcer complications. Results. By gastroduodenoscopy 10-14 days after ACS erosive gastritis or duodenitis was identified in 38 (90,5%) patients, gastric ulcer - in 4 (9.5%) patients. Hp infection was detected in 62% of cases (26 patients). Abdominal pain and/or dyspeptic syndromes were noted in 18 (42,9%) patients. After one month clinical signs of abdominal and dyspeptic syndromes were eliminated in all of patients. There were no bleeding from the upper GIT. Complete epithelization of gastric and duodenal lesions was achieved in 22 (52.4%) patients. A significant inverse correlation was found between endoscopic criteria of effectiveness and Hp infection (r = - 0,36, p = 0.021), endoscopic criteria of effectiveness and smoking (r = - 0,5, p = 0.002). Conclusion. The short course of pantoprazole for treatment of erosive and ulcerative gastric and duodenal lesions in patients taking dual antiplatelet therapy after ACS and urgent PCI is effective only in half of cases. Smoking cessation and eradication therapy in the presence of Hp infection can enhance the efficacy of treatment.Эффективность ингибиторов протонной помпы (ИПП) у пациентов с зрозивно-язвенными поражениями верхних отделов желудочно-кишечного тракта (ЖКТ), принимающих двойную антитромбоцитарную терапию, изучена недостаточно. Цель. Оценка эффективности применения пантопразола при лечении эрозивно-язвенных поражений желудка и ДПК у пациентов, получающих двойную антитромбоцитарную терапию аспирином и клопидогрелем после проведения неотложных чрескожных коронарных вмешательств (ЧКВ) в связи с острыми коронарными синдромами (ОКС). Материалы и методы. Обследованы 42 пациента, которым в связи с ОКС проведено неотложное ЧКВ. У всех пациентов при фиброгастродуоденоскопии (ФГДС) выявлены эрозивно-язвенные поражения желудка и ДПК. Биоптаты слизистой антрального отдела желудка исследовались для выявления Helicobacter pilory (Нр). Повторная ФГДС проводилась через один месяц. Пациентам назначали двойную антитромбоцитарную терапию аспирином и клопидогрелем, а для профилактики эрозивно-язвенных осложнений - пантопразол 40 мг в сутки. Результаты. При проведении ФГДС через 10-14 дней после ОКС у 38 (90,5%) пациентов выявлен эрозивный гастрит или дуоденит, у 4 (9,5%) пациентов - язва желудка. Нр инфекция выявлена в 62% случаев (26 пациентов). Абдоминальный болевой и/или диспепсический синдромы отмечены у 18 (42,9%) больных. Через один месяц клинические проявления абдоминального болевого и диспепсического синдромов устранены у всех пациентов. Кровотечений из верхних отделов ЖКТ не отмечено. Полная эпителизация поражений желудка и ДПК достигнута у 22 (52,4%) пациентов. Выявлена достоверная обратная корреляция между эндоскопическим критерием эффективности и Нр инфекцией (г = - 0,36, р = 0,021), эндоскопическим критерием эффективности и курением (г = - 0,5, р = 0,002). Заключение. Короткий курс терапии пантопразолом при лечении эрозивно-язвенных поражений желудка и ДПК у пациентов, принимающих двойную антитромбоцитарную терапию после перенесенного ОКС и неотложного ЧКВ, эффективен лишь в половине случаев. Отказ от курения и проведение эрадикационной терапии при наличии Нр-инфекции могут способствовать повышению эффективности лечения

Additional criteria for stratifying the ischemic stroke risk in patients with atrial fibrillation and one non-sex-related score on the CHA2DS2-VASC scale due to arterial hypertension

Purpose. Identification of characteristics, not included in the CHA2DS2-VASc scale, affecting the risk of ischemic stroke in patients with atrial fibrillation (AF) and one non-sex-related risk factor (RF), due to arterial hypertension (AH), of thromboembolic events on this scale.Цель. Выявление не входящих в шкалу CHA2DS2-VASc характеристик, влияющих на риск ишемического инсульта у пациентов с фибрилляцией предсердий (ФП) и одним не связанным с половой принадлежностью фактором риска (ФР) тромбоэмболических осложнений по этой шкале, обусловленным артериальной гипертонией (АГ) Материалы и методы. Проведено исследование «случай-контроль» по данным ретроспективного анализа историй болезни пациентов с ФП

СОРБЦИОННОЕ ИЗВЛЕЧЕНИЕ РЕНИЯ ИЗ ХРОМСОДЕРЖАЩИХ СУЛЬФАТНЫХ РАСТВОРОВ НИЗКООСНОВНЫМИ АНИОНИТАМИ СYBBER

Low-basic Cybber anionites with various functional groups and matrix type are tested for recovery of rhenium from multicomponent sulfuric acid solutions. It is established that anionite SX002 manifests an increased capacity during the sorption from solutions with a low Re content, while anionite ALX220 is applicable to recover Re at its high concentrations in the solution. The ionic background of the industrial solution affects the capacity of sorbents with respect to rhenium. When studying the kinetic characteristics, it is revealed that sorption processes on ionites are limited by the internal diffusion. The tests of ionites as applied to Cr-containing solutions indicate the possibility of using anionites ALX220 and SX002 to recover rhenium.Для извлечения рения из многокомпонентных серно-кислотных растворов опробованы образцы низкоосновных анионитов Cybber с различными функциональными группами и типом матрицы. Установлено, что анионит SX002 проявляет повышенную емкость при сорбции из растворов с низким содержанием Re, а ALX220 применим для извлечения Re при его высоких концентрациях в растворе. Ионный фон технологического раствора оказывает влияние на емкость сорбентов по рению. При изучении кинетических характеристик выявлено, что процессы сорбции на ионитах лимитируются внутренней диффузией. Проверка ионитов на технологических Cr-содержащих растворах свидетельствует о возможности применения анионитов ALX220 и SX002 для извлечения рения

Genetic diversity of wheat (Triticum aestivum L.) plants-regenerants produced by anther culture

The study of genetic diversity of wheat (Triticum aestivum L.) plants-regenerants produced by anther culture method from hybrids involved in the Latvian wheat breeding programme was performed. Flow cytometry was used to test ploidy of 3×103 cells of each green plantregenerant, and universal retrotransposon based iPBS (inter primer binding sites) method were used to establish genetic diversity of plants-regenerants. Progenies of 13 genetically distant hybrids were involved in the study. Most of plants-regenerants have leaves with mixoploid cells. Seeds were formed only by plants-regenerants that had cells with (2n = 6x) ploidy. Majority of fertile plantsregenerants have more than 40 % of hexaploid (6x) cells. The percentage of 6x cells in plants-regenerants and diversity in cell ploidy demonstrated association with mother plant (hybrid) genotype. Percent of spontaneous diplodization was also genotype-dependent. In this experiment colchicine treatment had no significant influence on outcome of fertile plants- regenerants. New dominant allele in a hybrid plant was found in comparison with both parents what indicated possible retrotransposon moving. Genetic diversity of the plants-regenerants obtained in anther culture is a combination of parent’s allele segregation and somaclonal variation

Mechanism of Disruption of the Amt-GlnK Complex by PII-Mediated Sensing of 2-Oxoglutarate

GlnK proteins regulate the active uptake of ammonium by Amt transport proteins by inserting their regulatory T-loops into the transport channels of the Amt trimer and physically blocking substrate passage. They sense the cellular nitrogen status through 2-oxoglutarate, and the energy level of the cell by binding both ATP and ADP with different affinities. The hyperthermophilic euryarchaeon Archaeoglobus fulgidus possesses three Amt proteins, each encoded in an operon with a GlnK ortholog. One of these proteins, GlnK2 was recently found to be incapable of binding 2-OG, and in order to understand the implications of this finding we conducted a detailed structural and functional analysis of a second GlnK protein from A. fulgidus, GlnK3. Contrary to Af-GlnK2 this protein was able to bind both ATP/2-OG and ADP to yield inactive and functional states, respectively. Due to the thermostable nature of the protein we could observe the exact positioning of the notoriously flexible T-loops and explain the binding behavior of GlnK proteins to their interaction partner, the Amt proteins. A thermodynamic analysis of these binding events using microcalorimetry evaluated by microstate modeling revealed significant differences in binding cooperativity compared to other characterized PII proteins, underlining the diversity and adaptability of this class of regulatory signaling proteins

Dianthracenylazatrioxa[8]circulene: synthesis, characterization and application in OLEDs

A soluble, green-blue fluorescent, pi-extended azatrioxa[8]circulene was synthesized by oxidative condensation of a 3,6-dihydroxycarbazole and 1,4-anthraquinone by using benzofuran scaffolding. This is the first circulene to incorporate anthracene within its carbon framework. Solvent-dependent fluorescence and bright green electroluminescence accompanied by excimer emission are the key optical properties of this material. The presence of sliding pi-stacked columns in the single crystal of dianthracenylazatrioxa[8]circulene is found to cause a very high electron-hopping rate, thus making this material a promising n-type organic semiconductor with an electron mobility predicted to be around 2.26 cm(2) V-1 s(-1). The best organic light-emitting diode (OLED) device based on the dianthracenylazatrioxa[8]circulene fluorescent emitter has a brightness of around 16 000 Cd m(-2) and an external quantum efficiency of 3.3 %. Quantum dot-based OLEDs were fabricated by using dianthracenylazatrioxa[8]circulene as a host matrix material.Peer reviewe

Влияние комплекса хитозан-ß-циклодекстрин с левофлоксацином на микрофлору ран и толстого кишечника осетра

The authors in the article presented the results of determining the effectiveness of using the chitosan-ß-cyclodextrin complex with levofloxacin in the healing of mechanical wounds of valuable commercial fish sturgeons and their feeding. The experiment was conducted based on the “Progressive biotechnologies in aquaculture” research laboratory of the Saratov State University of Genetics, Biotechnology and Engineering. N.I. Vavilov. The microflora of incised wounds and the large intestine of sturgeon fingerlings under the influence of fluoroquinolone, represented by levofloxacin based on cyclodextrin, included in the shell of high-molecular chitosan, was studied. The studied microbiological indicators were chosen to determine that changes in the total number of microorganisms show the nature of the course of the inflammatory/pathological process, which contributes to the development of microorganisms (including opportunistic pathogens) and lactic acid bacteria in the intestine. Therefore, they are essential physiological indicators of the formation of “ intestinal immunity. It was found that the use of cyclodextrin with levofloxacin in the treatment of incised wounds in sturgeons leads to a significant decrease in the total microbial number (TMC) on their surface (by 10 thousand times compared to the group without treatment). It has been shown that using cyclodextrin with levofloxacin in feeding sturgeons reduces the total microbial number in the large intestine. This complex is characterised by good solubility and bioavailability for fish. The future study results can be used in aquaculture to treat mechanical injuries received during transportation and sorting in the rearing process in fish.Представлены результаты определения эффективности применения комплекса хитозан-ß-циклодекстрин с левофлоксацином в заживлении механических ран ценных промысловых рыб – осетров и их кормлении. Эксперимент проводили на базе научно-исследовательской лаборатории «Прогрессивные биотехнологии в аквакультуре» Саратовского государственного университета генетики, биотехнологии и инженерии им. Н.И. Вавилова. Исследовалась микрофлора резаных ран и толстого кишечника сеголетков осетров под действием фторхинолона, представленного левофлоксацином на основе циклодекстрина, включенного в оболочку высокомолекулярного хитозана. Исследуемые микробиологические показатели были выбраны для определения на том основании, что изменения общего количества микроорганизмов показывают характер течения воспалительного/патологического процесса, способствующего развитию микроорганизмов (в т.ч. условно-патогенных) и молочнокислых бактерий в кишечнике, поэтому являются важными физиологическими показателями формирования «кишечного иммунитета». Было обнаружено, что применение при лечении резаных ран у осетров циклодекстрина с левофлоксацином приводит к значительному уменьшению общего микробного числа (ОМЧ) на их поверхности (в 10 тыс. раз по сравнению с группой без лечения). Показано, что использование в кормлении осетров циклодекстрина с левофлоксацином также снижает общее микробное число в толстом кишечнике. Данный комплекс характеризуется хорошей растворимостью и биодоступностью для рыб. Результаты исследования в перспективе могут найти применение в аквакультуре при лечении механических травм, полученных при перевозке и сортировке в процессе выращивания, у рыб