Charged rho meson production in neutrino-induced reactions at E_nu = 10 GeV

The neutrinoproduction of charged $\rho$ mesons on nuclei and nucleons is investigated for the first time at moderate energies ($\approx$ 10 GeV), using the date obtained with SKAT bubble chamber. No strong nuclear effects are observed in $\rho^+$ and $\rho^-$ production. The fractions of charged and neutral pions originating from $\rho$ decays are obtained and compared with higher energy data. From analysis of the obtained and available data on $\rho^+$ and $K^{*+}$(892) neutrinoproduction, the strangeness suppression factor in the quark string fragmentation is extracted: $\lambda_s = 0.18\pm0.03$. Estimations are obtained for cross sections of quasiexclusive single $\rho^+$ and coherent $\rho^+$ neutrinoproduction on nuclei. The estimated coherent cross section $\sigma_{\rho^+}^{coh}$ = (0.29$\pm0.16)\cdot 10^{-38}$ cm$^2$ is compatible with theoretical predictions.Comment: 7 pages, 6 figure

The total yields of K^+(892), Sigma^+(1385) and Sigma^0 in neutrino-induced reactions at <E_nu> = 10 GeV

Using the data obtained with SKAT bubble chamber, the total yields of $K^+(892)$, $\Sigma^+(1385)$ and $\Sigma^0$ are estimated for the first time in neutrino-induced reactions at moderate energies ($$ = 10.4 GeV). It is shown, that the recently observed \cite{ref1,ref2} enhancement of the $K^0$ and $\Lambda$ yields in $\nu A$ interactions (as compared to $\nu N$ interactions) is contributed only slightly by the $K^+(892)$ and $\Sigma^+(1385)$ production, respectively. The decay contribution to the $K^0$ and $\Lambda$ yields is found to be in qualitative agreement with higher energy ($\geq$ 40 GeV) data. It is shown, that the energy dependence of the $K^+(892)$ mean multiplicity in $\nu N$ interactions is approximately linear in the range of $\approx$ 10-60 GeV, while that for $\Sigma^0$ in $\nu A$ interactions (for $A$ = 20-21) is approximately logarithmic in the range of $\approx$ 10-150 GeV.Comment: 6 pages, 3 figure

A study of the nuclear medium influence on transverse momentum of hadrons produced in deep inelastic neutrino scattering

The influence of nuclear effects on the transverse momentum $(p_T)$ distributions of neutrinoproduced hadrons is investigated using the data obtained with SKAT propane-freon bubble chamber irradiated in the neutrino beam (with $E_{\nu}$ = 3-30 GeV) at Serpukhov accelerator. Dependences of $$on the kinematical variables of inclusive deep-inelastic scattering and of the produced hadrons are measured. It has been observed, that the nuclear effects cause an enhancement of$$ of hadrons (more pronounced for the positively charged ones) produced in the target fragmentation region at low invariant mass of the hadronic system (2 $< W <$ 4 GeV) or at low energies transferred to the current quark (2 $< \nu < 9$ GeV). At higher $W$ or $\nu$, no influence of nuclear effects on $$ is observed. Measurement results are compared with predictions of a simple model, incorporating secondary intranuclear interactions of hadrons (with a formation length extracted from the Lund fragmentation model), which qualitatively reproduces the main features of the data.Comment: 23 pages, 7 figure

The A - dependence of K0K^{0} and Λ\Lambda neutrinoproduction on nuclei

For the first time, the A- dependence of the production of $K^0$, $\Lambda$ and, for comparison, $\pi^-$ mesons is investigated in neutrinonuclear reactions, using the data obtained with SKAT bubble chamber. An exponential parametrization ($\sim A^{\beta}$) of the particle yields results in ${\beta}_{V^0} = 0.20 \pm 0.05$ for $V^0$ particles (combined $K^0$ and $\Lambda$), while for $\pi^-$ mesons the A- dependence is much weaker, ${\beta}_{\pi^-} = 0.068 \pm 0.007$. A nuclear enhancement of the ratio $K^0/\pi^-$ is found; this ratio increases from $0.055 \pm 0.013$ for $\nu N$- interactions up to $0.070 \pm 0.011$ at $A \approx 21$ and $0.099 \pm 0.011$ at $A \approx 45$. It is observed, that the multiplicity rise of $V^0$'s occures predominantely in the backward hemisphere of the hadronic c.m.s. It is shown, that the A- dependence of the nuclear enhancement of the ${\Lambda}^0$ and $\pi^-$ yields can be reproduced in the framework of a model, incorporating the secondary intranuclear interactions of pions originating from the primary $\nu N$- interactions, while only (29$\pm$9)% of that for $K^0$ at $A \approx 45$ can be attributed to intranuclear interactions.Comment: 18 pages, 8 figure

The yields of light meson resonances in neutrinonuclear interactions at <E_nu> = 10 GeV

The total yields of the all well-established light mesonic resonances (up to the $\phi$(1020) meson) are estimated in neutrinonuclear interactions at < E_nu > = 10 GeV, using the data obtained with SKAT bubble chamber. For some resonances, the yields in the forward and backward hemispheres in the hadronic c.m.s. are also extracted. From the comparison of the obtained and available higher-energy data, an indication is obtained that the resonance yields rise almost linearly as a function of the mean mass of the neutrinoproduced hadronic system. The fractions of pions originating from the light resonance decays are inferred.Comment: 15 pages, 7 figure

Гуморальный иммунитет к коклюшу в диадах «Мать и дитя»

Introduction. Infants younger than 3 months old are at high risk of severe pertussis, complications and pertussis-associated mortality. Newborns receive protection against pertussis from maternal antibodies transferred predominantly during late pregnancy. Neither disease, nor vaccination provides lifelong immunity against pertussis. So most of women have low antibody concentrations, leaving their newborn infant at a higher risk for disease in the first months of life.The aim of this study was to assess the concentration of antibodies against Вordetella pertussis among mother-baby dyads.Methods. We performed a cross-sectional study including 119 mother-baby dyads. Maternal antibodies were measured in venous blood specimens during the last trimester of pregnancy for women and in cord blood for newborn infants.Results. The median age was 30 (25; 34) years. The half of participants had unknown vaccination status (49,6%). Only 12,6% had a protective level (&gt;18 U/mL) of anti-pertussis antibodies, 74,8% of participants had a nonprotective (&lt;14 U/mL) level and 12,6% had an equivocal (14–18 U/mL) antibody concentrations. All newborns of seropositive women and 11,5% infants of women with an equivocal titers receive protection against pertussis. Transplacental transport ratio of antibodies against pertussis was higher in newborns of seropositive women.Conclusion. We revealed a huge proportion of pregnant women (87,4%) and newborns (77,3%) susceptible to pertussis. Maternal antibody level against pertussis was the major predictor of the antibody level in the infant.Введение. Дети первых 3 месяцев жизни – группа риска развития тяжёлых форм коклюша, осложнений и летальных исходов. Новорождённые получают защиту от коклюша трансплацентарно от матери, преимущественно в конце третьего триместра беременности. Ни перенесённая инфекция, ни вакцинация против коклюша не обеспечивают пожизненного иммунитета. Поэтому большинство женщин имеют низкие титры противококлюшных антител, а их новорождённые дети восприимчивы к данной инфекции в течение первых месяцев жизни.Цель: оценка концентрации антител к Вordetella pertussis в диадах «Мать и дитя».Методы. Мы провели поперечное исследование с включением 119 пар «Мать и дитя». Уровень материнских антител к коклюшу определялся в венозной крови женщины, в пуповинной крови оценивалась концентрация антител у ребёнка.Результаты. Медиана возраста составила 30 (25; 34) лет. Половина участниц не предоставили сведений о вакцинации против коклюша (49,6%). Только 12,6% имели защитный титр противококлюшных антител (&gt;18 ЕД/мл), у 74,8% участниц уровень антител был низким (&lt;14 ЕД/мл) и у 12,6% – неопределённым (14–18 ЕД/мл). Все дети серопозитивных женщин и 11,5% детей женщин с неопределённым уровнем антител получили защиту против коклюша от матери. Отношение концентрации антител в пуповинной и венозной крови было выше у серопозитивных женщин.Заключение. Мы выявили высокую долю беременных женщин (87,4%) и новорождённых (77,3%), восприимчивых к коклюшу. Трансплацентарная передача специфических антител была более эффективной при высоких титрах антител у матери.

МАЛОИЗВЕСТНЫЕ БАКТЕРИИ, ВЫДЕЛЕННЫЕ ПРИ ЗАБОЛЕВАНИЯХ ЧЕЛОВЕКА

The paper is devoted to the study of little-known and previously unknown bacteria isolated from patients with various diseases. Here we present the data on 22 strains that are little-known or previously unknown as human pathogens and isolated from patients with various diseases. Most of the isolates were found to have multiple antibiotic resistances. Moreover, in many conditions potentially pathogenic spore-forming bacteria were identified. Spore formation provides bacteria for survival in the environment and promotes high resistance to antiseptics and disinfectants. Spore-forming bacteria are high survival and especially dangerous as potential hospital-acquired infections because of its antibiotic resistance but the activity of this antibiotic therapy doesn’t concern microbial spores.Работа посвящена изучению малоизвестных и ранее не известных бактерий, изолированных у больных с патологиями различной локализации. Выделенные и изученные 22 штамма малоизвестных бактерий или вообще не описаны ранее как возбудители заболеваний человека, или обнаружены при патологии другой локализации. Большинство полученных бактерий обладает множественной  устойчивостью к различным  антибиотикам. При  разных  заболеваниях в материале обнаружено много потенциально-патогенных спорообразующих   бактерий. Спорообразование   обеспечивает бактериям  сохранение  жизнеспособности в окружающей среде и повышенную устойчивость к антисептикам и дезинфектантам. Спорообразующие бактерии хорошо   сохраняются   и особенно  опасны  в качестве потенциальных  возбудителей внутрибольничных   инфекций,   поскольку резистентны к антибиотикотерапии, активность которой не распространяется на микробные споры

Assessment of vitamin D level in the umbilical cord blood of the Arkhangelsk city infants born in winter time

Forthe child’s optimal growth and development, the normal provision with vitamin D isrequired. The vitamin D levelsin newborn depend directly on the mother’s provision with this vitamin, who is a single vitamin source for the child. The purpose of the study is to assess the provision with vitamin D in newborns of Arkhangelsk city in winter. 25(ОН)D determination in the blood serum of 55 newborns and their mothers was carried out using the method of the enzyme-linked immunosorbent assay at the laboratory of Arkhangelsk Children’s Regional Clinical Hospital. Resulting from the test carried out, only 4 (7%) children had the normal level of vitamin D, 36% (20 children) had the level corresponding to the deficiency: 14 (26% children) had the insufficiency of this vitamin, 17 (31% children) had a severe deficiency. The data obtained indicate the necessity to optimize the activities on the vitamin D deficiency prophylaxis in the pregnant women and support the prescription of vitamin D drugs to the newborns of Arkhangelsk city from the first days of the life