Structural and biochemical characterization of a novel ZntB (CmaX) transporter protein from Pseudomonas aeruginosa

The 2-TM-GxN family of membrane proteins is widespread in prokaryotes and plays an important role in transport of divalent cations. The canonical signature motif, which is also a selectivity filter, has a composition of Gly-Met-Asn. Some members though deviate from this composition, however no data are available as to whether this has any functional implications. Here we report the functional and structural analysis of CmaX protein from a pathogenic Pseudomonas aeruginosa bacterium, which has a Gly-Ile-Asn signature motif. CmaX readily transports Zn2+, Mg2+, Cd2+, Ni2+ and Co2+ ions, but it does not utilize proton-symport as does ZntB from Escherichia coli. Together with the bioinformatics analysis, our data suggest that deviations from the canonical signature motif do not reveal any changes in substrate selectivity or transport and easily alter in course of evolution

Verification and Improvement of Flamelet Approach for Non-Premixed Flames

Studies in the mathematical modeling of the high-speed turbulent combustion has received renewal attention in the recent years. The review of fundamentals, approaches and extensive bibliography was presented by Bray, Libbi and Williams. In order to obtain accurate predictions for turbulent combustible flows, the effects of turbulent fluctuations on the chemical source terms should be taken into account. The averaging of chemical source terms requires to utilize probability density function (PDF) model. There are two main approaches which are dominant in high-speed combustion modeling now. In the first approach, PDF form is assumed based on intuitia of modelliers (see, for example, Spiegler et.al.; Girimaji; Baurle et.al.). The second way is much more elaborate and it is based on the solution of evolution equation for PDF. This approach was proposed by S.Pope for incompressible flames. Recently, it was modified for modeling of compressible flames in studies of Farschi; Hsu; Hsu, Raji, Norris; Eifer, Kollman. But its realization in CFD is extremely expensive in computations due to large multidimensionality of PDF evolution equation (Baurle, Hsu, Hassan)

Experimental and Numerical Investigations of a Dual-Shaft Test Rig with Intershaft Bearing

This paper deals with an experimental study of a dual rotor test rig. This machine, which was developed and built at the Laboratoire de Tribologie et Dynamique des Systèmes, Ecole Centrale de Lyon, will be first presented. It is composed of two coaxial shafts that are connected by an intershaft bearing and rotate independently, each one driven by its own motor. Their lateral vibrations and whirling motion are coupled by the intershaft bearing. The experimental tests consisting in run-ups and the associated measured unbalance response of the dual rotor will be investigated. The influence of the rotation of each rotor on the critical speeds and the associated amplitudes will be discussed. Moreover, this paper presents a numerical model of the dual rotor. Correlations between the experimental and numerical tests will be investigated. The objective is to be able to predict phenomena observed in experiments, starting from a rather fine numerical model

Flamelet Model Application for Non-Premixed Turbulent Combustion

The current Final Report contains results of the study which was performed in Scientific Research Center 'ECOLEN' (Moscow, Russia). The study concerns the development and verification of non-expensive approach for modeling of supersonic turbulent diffusion flames based on flamelet consideration of the chemistry/turbulence interaction (FL approach). Research work included: development of the approach and CFD tests of the flamelet model for supersonic jet flames; development of the simplified procedure for solution of the flamelet equations based on partial equilibrium chemistry assumption; study of the flame ignition/extinction predictions provided by flamelet model. The performed investigation demonstrated that FL approach allowed to describe satisfactory main features of supersonic H 2/air jet flames. Model demonstrated also high capabilities for reduction of the computational expenses in CFD modeling of the supersonic flames taking into account detailed oxidation chemistry. However, some disadvantages and restrictions of the existing version of approach were found in this study. They were: (1) inaccuracy in predictions of the passive scalar statistics by our turbulence model for one of the considered test cases; and (2) applicability of the available version of the flamelet model to flames without large ignition delay distance only. Based on the results of the performed investigation, we formulated and submitted to the National Aeronautics and Space Administration our Project Proposal for the next step research directed toward further improvement of the FL approach

Spin Physics Experiments at NICA-SPD with polarized proton and deuteron beams

We propose to perform measurements of asymmetries of the Drell-Yan (DY) pairs production in collisions of non-polarized, longitudinally and transversally polarized protons and deuterons which provide an access to all leading twist collinear and TMD PDFs of quarks and anti-quarks in nucleons. The measurements of asymmetries in production of J/\Psi and direct photons will be performed as well simultaneously with DY using dedicated triggers. The set of these measurements will supply complete information for tests of the quark-parton model of nucleons at the QCD twist-two level with minimal systematic errors.Comment: Letter of Intent, 54 pages, 54 fugure

Cryo-EM structure of a tetrameric photosystem I from Chroococcidiopsis TS-821, a thermophilic, unicellular, non-heterocyst-forming cyanobacterium

Photosystem I (PSI) is one of two photosystems involved in oxygenic photosynthesis. PSI of cyanobacteria exists in monomeric, trimeric, and tetrameric forms, in contrast to the strictly monomeric form of PSI in plants and algae. The tetrameric organization raises questions about its structural, physiological, and evolutionary significance. Here we report the ∼3.72 Å resolution cryo-electron microscopy structure of tetrameric PSI from the thermophilic, unicellular cyanobacterium Chroococcidiopsis sp. TS-821. The structure resolves 44 subunits and 448 cofactor molecules. We conclude that the tetramer is arranged via two different interfaces resulting from a dimer-of-dimers organization. The localization of chlorophyll molecules permits an excitation energy pathway within and between adjacent monomers. Bioinformatics analysis reveals conserved regions in the PsaL subunit that correlate with the oligomeric state. Tetrameric PSI may function as a key evolutionary step between the trimeric and monomeric forms of PSI organization in photosynthetic organisms

Психологическая готовность специалиста к деятельности как педагогическая проблема

Introduction. The relevance of the article is due to the problem of increasing the requirements of modern society for the quality of professional training of graduates. The article talks about the need to form psychological readiness for the activities of young specialists as an integrated system of professional and personal qualities and properties, the result of which is expressed in the willingness of a specialist to solve current and promising work tasks.Purpose setting. The purpose of the study is to identify the key block of psychological readiness of a specialist to work in the logic of pedagogical science.Methodology and methods of the study. The analysis of scientific publications has shown that the problem of psychological readiness for professional activity is the subject of research by many scientists of general and military pedagogy. Based on the theoretical stage of the research, the authors came to the conclusion that the development of readiness for activity is facilitated by the special mental state of the individual and the presence of a model of actions and a focus on their implementation, which are determined by the availability of appropriate abilities and conditions necessary for the successful implementation of its activities, based on an understanding of the anticipatory reflection of reality, providing a preventive adaptation to the upcoming changes in external conditions or the formation of preparatory changes for future events. Therefore, psychological readiness for activity is a «preventive» adaptation to future labor events.Results. The results of the study include the description and analysis of the problem of psychological readiness for activity in the logic of psychology and pedagogy. The idea of the model of psychological readiness for activity, built on the principles of its implementation, is revealed; the content of each of its components is disclosed and the level criteria characteristic of each of them in the logic of high, medium and low is given. A step-by-step program for the formation of psychological readiness for activity is presented, including a diagnostic complex, the content of work at each stage, and options for the probabilistic result of preparedness.Conclusions. In the final part of the work, it is said that the research problem is practice-oriented and allows us to state that psychological readiness in activity contributes to ensuring high labor productivity, the development of professional qualities necessary for the work performed (initiative, active life position, organizational skills), high efficiency. Psychological readiness for activity is a «preventive» adaptation to future work events.Введение. Актуальность статьи обусловлена проблемой повышения требований современного общества к качеству профессиональной подготовки выпускников. В статье говорится о необходимости формировать психологическую готовность к деятельности молодых специалистов как интегрированную систему профессионально-личностных качеств и свойств, результат которой выражается в готовности специалиста решать актуальные и перспективные трудовые задачи.Постановка задачи. Цель исследования – выявление ключевого блока психологической готовности специалиста к деятельности в логике педагогической науки.Методика и методология исследования. Анализ научных публикаций показал, что проблема психологической готовности к профессиональной деятельности является предметом исследования многих ученых общей и военной педагогики. На основе проведенного теоретического этапа исследований авторы пришли к выводу о том, что развитию готовности к деятельности способствует особенное психическое состояние индивида, наличие у него модели действий и направленность на их реализацию, которые определяются наличием соответствующих способностей и условий, необходимых для успешного ее осуществления деятельности, опора на понимание опережающего отражения действительности, обеспечивающего предупредительное приспособление к предстоящим изменениям внешних условий или формирование подготовительных изменений для будущих событий. Поэтому психологическая готовность к деятельности представляет собой «предупредительное» приспособление к будущим трудовым событиям.К результатам исследования можно отнести описание и анализ проблемы психологической готовности к деятельности в логике психологии и педагогики. Раскрыты представление о модели психологической готовности к деятельности, построенной на принципах ее реализации; содержание каждого ее компонента и дана уровневая критериальная характеристика каждого из них в логике высокого, среднего и низкого. Представлена поэтапная программа формирования психологической готовности к деятельности, включающая диагностический комплекс, содержание работы на каждом этапе, и варианты вероятностного результата подготовленности.Выводы. В заключительной части работы говорится о том, что проблема исследования носит практико-ориентированный характер и позволяет констатировать, что психологическая готовность в деятельности способствует обеспечению высокой производительности труда, развитию профессиональных качеств, необходимых для выполняемой работы (инициативность, активная жизненная позиция, организаторские умения), высокая работоспособность. Психологическая готовность к деятельности представляет собой «предупредительное» приспособление к будущим трудовым событиям

Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS

The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda and anti-lambda produced in the current fragmentation region exhibit different behaviours as a function of x and xF . The measured x and xF dependences of D^lambda_LL are compatible with zero, while D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the frame of recent model calculations.Comment: 13 pages, 7 figure