Double-K-vacancy states in electron-impact single ionization of metastable two-electron N5+(1s2s 3S1) ions

The role of hollow states intermediately produced in electron-impact ionization of metastable He-like N5+(1s2s3S1) ions has been investigated in detail. A crossed-beam setup and suitable experimental techniques were employed for the measurement of accurate absolute cross sections and precise energy-scan data. Fine structures arising from K-shell excitations and associated resonances have been observed for this two-electron ion with less than ±0.5 eV uncertainty on the energy scale. Fine details, such as interference of the reaction pathways of direct ionization and excitation with capture of the incident electron followed by double-Auger decay, could be revealed. Ab initio calculations based on the convergent close coupling (CCC) approach are in good agreement with the experiment

Simulation of a GOx-GCH4 Rocket Combustor and the Effect of the GEKO Turbulence Model Coefficients

In this study, a single injector methane-oxygen rocket combustor is numerically studied. The simulations included in this study are based on the hardware and experimental data from the Technical University of Munich. The focus is on the recently developed generalized k–w turbulence model (GEKO) and the effect of its adjustable coefficients on the pressure and on wall heat flux profiles, which are compared with the experimental data. It was found that the coefficients of ‘jet’, ‘near-wall’, and ‘mixing’ have a major impact, whereas the opposite can be deduced about the ‘separation’ parameter Csep, which highly influences the pressure and wall heat flux distributions due to the changes in the eddy-viscosity field. The simulation results are compared with the standard k–# model, displaying a qualitatively and quantitatively similar behavior to the GEKO model at a Csep equal to unity. The default GEKO model shows a stable performance for three oxidizer-to-fuel ratios, enhancing the reliability of its use. The simulations are conducted using two chemical kinetic mechanisms: Zhukov and Kong and the more detailed RAMEC. The influence of the combustion model is of the same order as the influence of the turbulence model. In general, the numerical results present a good or satisfactory agreement with the experiment, and both GEKO at Csep = 1 or the standard k–# model can be recommended for usage in the CFD simulations of rocket combustion chambers, as well as the Zhukov–Kong mechanism in conjunction with the flamelet approach

In vitro fertilization as a method of infertility treatment in women with type 1 diabetes mellitus

Some patients with type 1 diabetes have anovulation, tubal occlusion, male factor and other causes of infertility which require IVF procedure. We examined 20 women with type 1 diabetes, in which pregnancy occurred as a result of ART, at the stage IVF protocol planning, during pregnancy course and delivery. One of the patients underwent IVF procedure twice. Mean age of the patients who applied to the Department of assisted reproductive technologies was 33±6 years, duration of infertility varied from 3 to 15 years. Two patients were performed donor oocytes transfer (patients with Turner Syndrome and Swyer Syndrome). In 70% of patients the method of CSII was used. Assessment of carbohydrate metabolism was based on the level of glycated hemoglobin A1c (HbA1c), plasma glucose level measured at least 8 times a day and results of continuous glucose monitoring (CGM). 18 singleton pregnancies and three multiple gestations (dichorionic diamniotic twins) occurred as a result of IVF. In 12 women delivery occurred on the 37–39th weeks of gestation, in 9 patients pregnancy was terminated on the 34–36th weeks. In all the cases it was live birth. Birth weight above the 90th percentile had 6 newborns

БИФИДОГЕННЫЕ СВОЙСТВА БИОТЕХНОЛОГИЧЕСКОГО АНАЛОГА ЛАКТОФЕРРИНА ЧЕЛОВЕКА

Background:  Recent research shows that the growth and development of the gastrointestinal  tract of children fed by breast milk is more intense than that of the formula fed, since the human lactoferrin contained in the breast milk is a factor that stimulates cell growth. Therefore, the possibility of using exogenous lactoferrin will be of great importance in the nutrition of infants.Objektive: To study the bifidogenic properties of the biotechnological analogue of human lactoferrin. Methods: Kinetics of growth and CFU titer of bifidobacterial culture in the presence of a biotechnological analogue of human lactoferrin (0,05–5 mg /ml) was determined.Results: It has been shown that different concentrations of the protein can have both a stimulating (for B. bifidum and B. infantis) and inhibitory (for B. longum) effect on the growth of bifidobacteria, which is due to the affinity of lactoferrin binding to them. It seems important to further study the stimulating effect of this protein on the growth of lactobacilli in the intestine of the child.Conclusion:  Due to bifidogenic and high bactericidal action, lactoferrin can be effective in feeding newborns.Обоснование.   Новейшие исследования  показывают,  что  рост  и развитие  желудочно-кишечного  тракта  детей, вскармливаемых  материнским молоком,  происходит  интенсивнее,  чем у вскармливаемых  молочными смесями, поскольку содержащийся в нем лактоферрин человека является фактором, стимулирующим клеточный рост. Именно поэтому возможность  использования экзогенного лактоферрина  будет иметь большую значимость в питании грудных детей.Цель  исследования — изучить бифидогенные  свойства биотехнологического аналога  лактоферрина человека.Методы. Определялась кинетика роста и КОЕ-титр культивирования бифидобактерий в присутствии биотехнологического  аналога лактоферрина человека.Результаты. Показано, что различные концентрации данного белка (0,05–5 мг/мл) могут оказывать как стимулирующее (для Bifidobacterium bifidum и Bifidobacterium infantis), так и ингибирующее (для Bifidobacterium longum) действие в отношении роста бифидобактерий,  что обусловлено аффинностью  связывания с ними лактоферрина. Представляется  важным дальнейшее изучение стимулирующего эффекта  этого белка на рост лактобацилл в кишечнике ребенка.Заключение. Благодаря  бифидогенному и выраженному бактерицидному действию лактоферрин может быть использован в лечебном питании новорожденных

Influence of Polyisobutylene Kerosene Additive on Combustion Efficiency in a Liquid Propellant Rocket Engine

The combustion of kerosene with the polymer additive polyisobutylene (PIB) was experimentally investigated. The aim of the study was to measure the effect of PIB kerosene on the efficiency of combustion chamber cooling and the combustion efficiency of the liquid propellant for a rocket engine operating on kerosene and gaseous oxygen (GOX). The study was conducted on an experimental rocket engine using kerosene wall film cooling in the combustion chamber. Fire tests showed that the addition of polyisobutylene to kerosene had no significant effect on the combustion efficiency. However, analysis of the wall temperature measurement results showed that the use of PIB kerosene is more effective for film cooling than pure kerosene, which can increase the efficiency of combustion chamber cooling and subsequently increase its reliability and reusability. Thus, the findings of this study are expected to be of use in further investigations of wall film cooling efficiency

Electron impact ionization of ground-state and metastable Li+ ions

Direct ionization of ground-state Li+(1s2 1S0) and metastable Li+(1s2s 3S1) ions by electron impact has been studied in the energy range from threshold to 1000 eV using state-of-the-art experimental and theoretical approaches. Absolute cross sections obtained by crossing a beam of Li+(1s2) ions with a beam of electrons and results of convergent close coupling (CCC) calculations agree within experimental error bars of approximately 10%. Mixed beams of Li+(1s2) and Li+(1s2s 3S) ions were also prepared and apparent cross sections were measured. Good agreement with CCC theory is obtained assuming suitable fractions of metastable ions in the parent beam

Indirect contributions to electron-impact ionization of Li+ (1s2s S1 3) ions: Role of intermediate double- K -vacancy states

Fine details of the cross section for electron-impact ionization of metastable two-electron Li+ (1s2s 3S1) ions are scrutinized by both experiment and theory. Beyond direct knockoff ionization, indirect ionization mechanisms proceeding via formation of intermediate double-K-vacancy (hollow) states either in a Li+ ion or in a neutral lithium atom and subsequent emission of one or two electrons, respectively, can contribute to the net production of Li2+ ions. The partial cross sections for such contributions are less than 4% of the total single-ionization cross section. The characteristic steps, resonances, and interference phenomena in the indirect ionization contribution are measured with an experimental energy spread of less than 0.9 eV and with a statistical relative uncertainty of the order of 1.7%, requiring a level of statistical uncertainty in the total single-ionization cross section of better than 0.05%. The measurements are accompanied by convergent-close-coupling calculations performed on a fine energy grid. Theory and experiment are in remarkable agreement concerning the fine details of the ionization cross section. Comparison with previous R-matrix results is less favorable

BIFIDOGENIC PROPERTIES OF A BIOTECHNOLOGICAL ANALOGUE OF HUMAN LACTOFERRIN

Background:  Recent research shows that the growth and development of the gastrointestinal  tract of children fed by breast milk is more intense than that of the formula fed, since the human lactoferrin contained in the breast milk is a factor that stimulates cell growth. Therefore, the possibility of using exogenous lactoferrin will be of great importance in the nutrition of infants.Objektive: To study the bifidogenic properties of the biotechnological analogue of human lactoferrin. Methods: Kinetics of growth and CFU titer of bifidobacterial culture in the presence of a biotechnological analogue of human lactoferrin (0,05–5 mg /ml) was determined.Results: It has been shown that different concentrations of the protein can have both a stimulating (for B. bifidum and B. infantis) and inhibitory (for B. longum) effect on the growth of bifidobacteria, which is due to the affinity of lactoferrin binding to them. It seems important to further study the stimulating effect of this protein on the growth of lactobacilli in the intestine of the child.Conclusion:  Due to bifidogenic and high bactericidal action, lactoferrin can be effective in feeding newborns

Physics book: CRYRING@ESR

The exploration of the unique properties of stored and cooled beams of highly-charged ions as provided by heavy-ion storage rings has opened novel and fascinating research opportunities in the realm of atomic and nuclear physics research. Since the late 1980s, pioneering work has been performed at the CRYRING at Stockholm (Abrahamsson et al. 1993) and at the Test Storage Ring (TSR) at Heidelberg (Baumann et al. 1988). For the heaviest ions in the highest charge-states, a real quantum jump was achieved in the early 1990s by the commissioning of the Experimental Storage Ring (ESR) at GSI Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt (Franzke 1987) where challenging experiments on the electron dynamics in the strong field regime as well as nuclear physics studies on exotic nuclei and at the borderline to atomic physics were performed. Meanwhile also at Lanzhou a heavy-ion storage ring has been taken in operation, exploiting the unique research opportunities in particular for medium-heavy ions and exotic nuclei (Xia et al. 2002)