Упрочнение трибомодификацией вермикулитом

Приведены результаты исследований износостойкости трибосопряжения «коленчатый вал – вкладыш подшипника» судового дизеля после трибомодификации шеек вала (сталь 40Х твердостью 230 НВ) композитами на основе вермикулита. В результате модифицирования на поверхности стали формируется тонкопленочное износостойкое металлокерамическое покрытие.The results of researches of wear resistance of units of "cranked shaft – the bearing" marine diesel after tribomodification of the shaft (steel 40X with hardness 230 HB) composites based on vermiculite. In the result of the modification on the surface of the steel is formed thin-film wear-resistant ceramic-metal coating

Nanostructural organization of naturally occurring composites - part II: silica-chitin-based biocomposites

Investigations of the micro- and nanostructures and chemical composition of the sponge skeletons as examples for natural structural biocomposites are of fundamental scientific relevance. Recently, we show that some demosponges (Verongula gigantea, Aplysina sp.) and glass sponges (Farrea occa, Euplectella aspergillum) possess chitin as a component of their skeletons. The main practical approach we used for chitin isolation was based on alkali treatment of corresponding external layers of spicules sponge material with the aim of obtaining alkali-resistant compounds for detailed analysis. Here, we present a detailed study of the structural and physicochemical properties of spicules of the glass sponge Rossella fibulata. The structural similarity of chitin derived from this sponge to invertebrate alpha chitin has been confirmed by us unambiguously using physicochemical and biochemical methods. This is the first report of a silica-chitin composite biomaterial found in Rossella species. Finally, the present work includes a discussion related to strategies for the practical application of silica-chitin-based composites as biomaterials

Геопространственное распределение госпитальных ресурсов в региональных травматологических системах (обзор зарубежной литературы)

The review presents the results of foreign studies related to geospatial analysis and modeling of the distribution of trauma centers and helicopter emergency medical services in developed regional trauma systems. The optimal number and geographical location of the trauma centers in the region is determined taking into account the timing of the delivery of victims to the trauma centers of a high level, population density, hospitalization of patients with severe trauma, and the frequency of inter-hospital transfers. The distribution of hospital resources of the trauma system should be based on the needs of the population, and vary depending on the geographical and social characteristics of the region. В обзоре представлены результаты зарубежных исследований, касающихся геопространственного анализа и моделирования распределения травмоцентров и вертолетных баз скорой медицинской помощи в развитых региональных травматологических системах. Оптимальное количество и географическое расположение травмоцентров в регионе определяется с учетом сроков доставки пострадавших в травмоцентры высокого уровня, плотности населения, объема госпитализаций пациентов с тяжелой травмой, частоты межбольничных переводов. Распределение госпитальных ресурсов травматологической системы должно основываться на потребностях населения, варьировать в зависимости от географических и социальных особенностей региона.

Measurement of the K+→μ+νμγK^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma} decay form factors in the OKA experiment

A precise measurement of the vector and axial-vector form factors difference $F_V-F_A$ in the $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ decay is presented. About 95K events of $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ are selected in the OKA experiment. The result is $F_V-F_A=0.134\pm0.021(stat)\pm0.027(syst)$. Both errors are smaller than in the previous $F_V-F_A$ measurements.Comment: 9 pages, 8 figure

Факторы риска и профилактика нозокомиальной пневмонии при политравме

Nosocomial pneumonia (NK) is one of the most frequent complications of polytrauma leading to death. Meanwhile, the recommendations on prevention of NK in case of polytrauma have not been specified so far. This is due in large part to the lack of study of the pathophysiology of severe combined trauma. The review presents the results of modern experimental and clinical studies of the effect of shock, immune distress syndrome, posttraumatic immunosuppression, the phenomenon of mutual aggravation of lesions, age, sex, concomitant pathology on the risk of NK in polytrauma. The role of iatrogenic risk factors for NK in polytrauma – intubation of trachea and artificial lung ventilation (AVL), massive hemotransfusions, immobilization, the phenomenon of “second strike” after multiple surgeries has been determined. The most effective measures of NK prevention are reduction of the duration of AVL, prevention of oropharyngeal colonization and aspiration in case of AVL, use of inhalation antibacterial drugs, antishock measures, early mobilization of the patient, the earliest possible stable functional osteosynthesis by minimally traumatic methods. The data on the effectiveness of selective decontamination of intestines, probiotics and glucocorticosteroids for the prevention of NK in polytrauma are inconsistent. A promising area of NK prophylaxis may be the development of agents that regulate the complex mechanisms of immune response to polytrauma and prevent secondary acute lung injury and post-traumatic immunosuppression.Нозокомиальная пневмония (НКП) относится к наиболее частым осложнениям политравмы (ПТ), приводящим к смерти. Между тем рекомендации по профилактике НКП при ПТ к настоящему времени не конкретизированы. Во многом это связано с недостаточной изученностью патофизиологии тяжелой сочетанной травмы. В обзоре представлены результаты современных экспериментальных и клинических исследований влияния шока, иммунного дистресс-синдрома, посттравматической иммуносупрессии, феномена взаимного отягощения повреждений, возраста, пола, сопутствующей патологии на риск развития НКП при ПТ. Определена роль ятрогенных факторов риска НКП при ПТ – интубации трахеи и искусственная вентиляция легких (ИВЛ), массивные гемотрансфузии, иммобилизации, феномен «второго удара» после множественных операций. Наиболее эффективными мерами профилактики НКП являются сокращение продолжительности ИВЛ, предупреждение колонизации ротоглотки и аспирации при ИВЛ, применение ингаляционных антибактериальных препаратов, противошоковые мероприятия, ранняя мобилизация пациента, максимально ранний стабильно-функциональный остеосинтез малотравматичными методами. Данные об эффективности селективной деконтаминации кишечника, пробиотиков и глюкокортикостероидов для профилактики НКП при ПТ противоречивы. Перспективным направлением профилактики НКП может быть разработка средств, при помощи которых регулируются сложные механизмы иммунного ответа на ПТ и предупреждающих вторичное острое повреждение легких и посттравматическую иммуносупрессию

Search for leptonic decays of D0 mesons

We search for the flavor-changing neutral current decays D0\to mu+mu- and D0\to e+e-, and for the lepton-flavor violating decays D0\to e\pm mu\mp using 660 fb^-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no evidence for any of these decays. We obtain significantly improved upper limits on the branching fractions: B(D0\to mu+mu-)<1.4x10-7, B(D0\to e+e-)<7.9x10-8, and B(D0\to e+mu-)+B(D0\to mu+e-)<2.6x10-7 at 90% confidence level.Comment: 6 pages, 3 figure

Search for CP violation in the decays D(s)+→KS0π+D^+_{(s)} \to K_S^0\pi^+ and D(s)+→KS0K+D^+_{(s)} \to K_S^0K^+

We have searched for CP violation in the charmed meson decays $D^{+}_{(s)}\to K^0_S\pi^+$ and $D^{+}_{(s)}\to K^0_S K^+$ using 673 fb$^{-1}$ of data collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No evidence for CP violation is observed. We report the most sensitive CP asymmetry measurements to date for these decays: $A_{CP}^{D^+\to K^0_S\pi^+}=(-0.71\pm0.19\pm0.20)$, $A_{CP}^{D^+_s\to K^0_S\pi^+}=(+5.45\pm2.50\pm0.33)$, $A_{CP}^{D^+\to K^0_S K^+}=(-0.16\pm0.58\pm0.25)$, and $A_{CP}^{D^+_s\to K^0_S K^+}=(+0.12\pm0.36\pm0.22)$, where the first uncertainties are statistical and the second are systematic

Measurements of Charmless Hadronic b->s Penguin Decays in the pi+pi-K+pi- Final State and First Observation of B0 -> rho0K+pi-

We report measurements of charmless hadronic B^0 decays into the pi+pi-K+pi+ final state. The analysis uses a sample of 657x10^6 BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider at the Y(4S) resonance. The decay B^0 -> rho0 Kpi is observed for the first time; the significance is 5.0sigma and the corresponding partial branching fraction for M_Kpi in (0.75,1.20) GeV/c^2 is [2.8 +- 0.5(stat) +-0.5(syst)] x 10^{-6}. We also obtain the first evidence for B^0 -> f0Kpi with 3.5sigma significance and for B^0 -> pi+pi-K*0 with 4.5sigma significance. For the two-body decays B^0 -> rho0K*0 and B^0 -> f0K*0, the significances are 2.7sigma and 2.5sigma, respectively, and the upper limits on the branching fractions are 3.4x10^{-6} and 2.2x10^{-6} at 90% confidence level.Comment: 6 pages, 3 figures. accepted by PRD(RC

Evidence of time-dependent CP violation in the decay B0 to D*+D*-

We report a measurement of the CP-odd fraction and the time-dependent CP violation in B0 to D*+D*- decays, using 657.10^6 BBbar events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure a CP-odd fraction of Rperp=0.125+/-0.043(stat)+/-0.023(syst). From the distributions of the proper-time intervals between a B0to D*+D*- decay and the other B meson in the event, we obtain evidence of CP violation with measured parameters AD*+D*-=0.15+/-0.13(stat)+/-0.04(syst) and SD*+D*-=-0.96+/-0.25(stat)-0.16+0.13(syst).Comment: Published in PR

Study of the B→X(3872)(→D∗0Dˉ0)KB\to X(3872)(\to D^{*0}\bar D^0)K decay

We present a study of $B\to X(3872)K$ with X(3872) decaying to $D^{*0}\bar D^0$ using a sample of 657 million $B\bar B$ pairs recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. Both $D^{*0}\to D^0\gamma$ and $D^{*0}\to D^0\pi^0$ decay modes are used. We find a peak of $50.1^{+14.8}_{-11.1}$ events with a mass of $(3872.9^{+0.6 +0.4}_{-0.4 -0.5}){\rm MeV}/c^2$, a width of $(3.9^{+2.8 +0.2}_{-1.4 -1.1}){\rm MeV}/c^2$ and a product branching fraction ${\cal B}(B\to X(3872)K)\times{\cal B}(X(3872)\to D^{*0}\bar D^0)=(0.80\pm0.20\pm0.10)\times10^{-4}$, where the first errors are statistical and the second ones are systematic. The significance of the signal is $6.4\sigma$. The difference between the fitted mass and the $D^{*0}\bar D^0$ threshold is calculated to be $(1.1^{+0.6 +0.1}_{-0.4 -0.3}){\rm MeV}/c^2$. We also obtain an upper limit on the product of branching fractions ${\cal B}(B\to Y(3940)K)\times{\cal B}(Y(3940)\to D^{*0}\bar D^0)$ of $0.67\times10^{-4}$ at 90% CL.Comment: 7 pages, 3 figures, BELLE-CONF-0832 contributed to ICHEP 2008, revised and submitted to Phys. Rev. D R