The hydrogenation of metals upon interaction with water

Hydrogen evolution at 600 deg and 5 x 10 to the 7th power - 10 to the 6th power torr from AVOOO Al samples, which were pickled in 10 percent NaOH, is discussed. An H evolution kinetic equation is derived for samples of equal vol. and different surfaces (5 and 20 sq cm). The values of the H evolution coefficient K indicated an agreement with considered H diffusion mechanism through an oxide layer. The activation energy for the H evolution process, obtained from the K-temp. relation, was 13,000 2000 cal/g-atom

ON SOME PROBLEMS OF DISSERTATION OPPONENCY

Introduction. Currently, there is a restructuring of the system of training scientific and scientific-pedagogical personnel of the highest qualification. A number of the top-ranking universities and research institutes are given the right to award their own academic degrees. However, the overwhelming majority of dissertational councils (about 2000) continue to work under the guidance and in accordance with the regulatory documents of the Higher Attestation Commission. Therefore, the improvement of the existing system is still relevant. The aims of this article are the following: to consider the main problems and trends emerging in the process of opposing dissertations; to find out the difficulties and their causes; to define possible ways to reduce current problems. Methodology and research methods. The methods involve: analysis of normative documents and scientific publications; methods of expert assessments, self-reflection and synthesis of personal experience of the author. Results and scientific novelty. The main objectives and the existing drawbacks of the work of official opponents are identified. The following questions that arise when opposing dissertations are discussed: the choice and appointment of official opponents by the Dissertation Council, the specifics of the opponents’ performance in the defense process and the payment for their work. It is noted that increasing requirements for opposing dissertations and opponents themselves, increasing the responsibility of opponents leads to additional difficulties in their work, in particular, the increase in labour costs that are not adequately compensated. It is concluded that many problems in opposing dissertations are objective in nature and cannot be overcome only by the forces of the opponent himself. Possible ways of solving the detected problems are indicated. Accordingly, along with increasing requirements and responsibilities in regulatory documents, a complex of the organizational and technological measures should be provided to facilitate the work of the opponent, his additional stimulation, including the financial one.Practical significance. The author believes that the approaches and recommendations proposed in this article will help to increase the effectiveness of the opponents’ work and, accordingly, assessment system enhancement of the research consistency and academic degrees awarding.Введение. В настоящее время в России происходит перестройка системы подготовки и аттестации научных и научно-педагогических кадров. Ряду сильнейших вузов и НИИ уже предоставлено право самостоятельно присуждать ученые степени. Однако подавляющая часть диссертационных советов (около 2000) продолжает работать под руководством Высшей аттестационной комиссии (ВАК) и в соответствии со старыми нормативными актами, поэтому многие вопросы реорганизации и совершенствования сложившейся системы остаются пока открытыми и сохраняют свою актуальность. Цели публикации – обсудить основные тенденции процесса оппонирования диссертационных изысканий, выявить его сложности и причины их возникновения; обозначить возможные варианты нивелирования имеющихся проблем. Методы и методики. В ходе исследования использовались анализ содержания нормативных документов и научных публикаций, методы экспертных оценок, рефлексии и обобщения личного опыта автора. Результаты и научная новизна. Обозначены основные задачи и существующие недостатки деятельности оппонентов. Рассмотрены вопросы, связанные с выбором и назначением диссертационными советами официальных оппонентов, спецификой их труда и его оплатой. Показано, что возросшие требования к оппонированию диссертаций и самим оппонентам привели к существенному увеличению их трудовых и временных затрат, которые практически не компенсируются. Сделан вывод о том, что многие сложности оппонирования, препятствующие подготовке качественных отзывов на диссертации, носят объективный характер и не могут быть преодолены силами самих оппонентов. В связи с этим, наряду с повышением, их ответственности в нормативных документах следует предусмотреть комплекс организационных и технологических мер, облегчающих решение текущих задач оппонирования и направленных на его дополнительное, в том числе финансовое, стимулирование. Практическая значимость. Автор рассчитывает, что предложенные им подходы к решению обнаруженных проблем и рекомендации, изложенные в данной статье, будут способствовать повышению эффективности функционирования института оппонирования, совершенствованию системы оценки состоятельности научных исследований и присуждения научных степеней.

Statistical analysis of Fisher et al. PBPK model of trichloroethylene kinetics.

Two physiologically based pharmacokinetic models for trichloroethylene (TCE) in mice and humans were calibrated with new toxicokinetic data sets. Calibration is an important step in model development, essential to a legitimate use of models for research or regulatory purposes. A Bayesian statistical framework was used to combine prior information about the model parameters with the data likelihood to yield posterior parameter distributions. For mice, these distributions represent uncertainty. For humans, the use of a population statistical model yielded estimates of both variability and uncertainty in human toxicokinetics of TCE. After adjustment of the models by Markov chain Monte Carlo sampling, the mouse model agreed with a large part of the data. Yet, some data on secondary metabolites were not fit well. The posterior parameter distributions obtained for mice were quite narrow (coefficient of variation [CV] of about 10 or 20%), but these CVs might be underestimated because of the incomplete fit of the model. The data fit, for humans, was better than for mice. Yet, some improvement of the model is needed to correctly describe trichloroethanol concentrations over long time periods. Posterior uncertainties about the population means corresponded to 10-20% CV. In terms of human population variability, volumes and flows varied across subject by approximately 20% CV. The variability was somewhat higher for partition coefficients (between 30 and 40%) and much higher for the metabolic parameters (standard deviations representing about a factor of 2). Finally, the analysis points to differences between human males and females in the toxicokinetics of TCE. The significance of these differences in terms of risk remains to be investigated

Looking for a time independent Hamiltonian of a dynamical system

In this paper we introduce a method for finding a time independent Hamiltonian of a given dynamical system by canonoid transformation. We also find a condition that the system should satisfy to have an equivalent time independent formulation. We study the example of damped oscillator and give the new time independent Hamiltonian for it, which has the property of tending to the standard Hamiltonian of the harmonic oscillator as damping goes to zero.Comment: Some references added, LATEX fixing

Modeling GRB 050904: Autopsy of a Massive Stellar Explosion at z=6.29

GRB 050904 at redshift z=6.29, discovered and observed by Swift and with spectroscopic redshift from the Subaru telescope, is the first gamma-ray burst to be identified from beyond the epoch of reionization. Since the progenitors of long gamma-ray bursts have been identified as massive stars, this event offers a unique opportunity to investigate star formation environments at this epoch. Apart from its record redshift, the burst is remarkable in two respects: first, it exhibits fast-evolving X-ray and optical flares that peak simultaneously at t~470 s in the observer frame, and may thus originate in the same emission region; and second, its afterglow exhibits an accelerated decay in the near-infrared (NIR) from t~10^4 s to t~3 10^4 s after the burst, coincident with repeated and energetic X-ray flaring activity. We make a complete analysis of available X-ray, NIR, and radio observations, utilizing afterglow models that incorporate a range of physical effects not previously considered for this or any other GRB afterglow, and quantifying our model uncertainties in detail via Markov Chain Monte Carlo analysis. In the process, we explore the possibility that the early optical and X-ray flare is due to synchrotron and inverse Compton emission from the reverse shock regions of the outflow. We suggest that the period of accelerated decay in the NIR may be due to suppression of synchrotron radiation by inverse Compton interaction of X-ray flare photons with electrons in the forward shock; a subsequent interval of slow decay would then be due to a progressive decline in this suppression. The range of acceptable models demonstrates that the kinetic energy and circumburst density of GRB 050904 are well above the typical values found for low-redshift GRBs.Comment: 45 pages, 7 figures, and ApJ accepted. Revised version, minor modifications and 1 extra figur

Avoiding spurious feedback loops in the reconstruction of gene regulatory networks with dynamic bayesian networks

Feedback loops and recurrent structures are essential to the regulation and stable control of complex biological systems. The application of dynamic as opposed to static Bayesian networks is promising in that, in principle, these feedback loops can be learned. However, we show that the widely applied BGe score is susceptible to learning spurious feedback loops, which are a consequence of non-linear regulation and autocorrelation in the data. We propose a non-linear generalisation of the BGe model, based on a mixture model, and demonstrate that this approach successfully represses spurious feedback loops

Competence-based approach while teaching fundamental science subjects at medical university

The aim of the study is to analyze the features of the competence approach application in the theoretical and natural science subjects’ teaching in medical school.Methods. The method of expert estimation is used in order to find out main tendencies and problems arising in the course of professional competencies development. The implementation of problem-oriented method in fundamental disciplines’ teaching is applied.Results. The effect of the competence approach on educational process is shown in the teaching experience of pathological anatomy and statistics. The problems and complicating factors faced by teacher are identified. The basic approaches facilitating the development of professional competencies based on a fixed time allotted for studying a particular discipline are proposed.Scientific novelty and practical significance. The proposed approaches and practical recommendations will enable to form more efficiently the competences in fundamental disciplines. The implementation of competence approach in teaching the fundamental science subjects requires adjustments of substantial and methodological levels of training including the active use of information technologies and a substantial increase in the role of seminars and self-studies. The advantage of the proposed approaches concludes in their universality: with some adjustment, they can be used in teaching other subjects, regardless of the specifics and the type of educational institution.Цель статьи – анализ особенностей применения компетентностного подхода в преподавании теоретических и естественнонаучных дисциплин в медицинском вузе. Методы. При выявлении основных тенденций и проблем, возникающих при выработке профессиональных компетенций, использовалась экспертная оценка. Для формирования компетенций по фундаментальным дисциплинам применялся проблемно-ориентированный подход к обучению. Результаты. Показано влияние компетентностного подхода на учебный процесс на примере подготовки по дисциплинам «Патологическая анатомия» и «Статистика». Описаны проблемы, возникающие у преподавателя, и факторы, осложняющие обучение. Предложены возможные варианты выработки профессиональных компетенций с учетом фиксированного времени, отпущенного на изучение конкретной дисциплины. Научная новизна и практическая значимость. Предложенные подходы и практические рекомендации позволят более эффективно формировать компетенции по фундаментальным дисциплинам. Реализация компетентностного подхода в преподавании теоретических и естественнонаучных дисциплин требует корректировки содержательного и методического уровней обучения с активным использованием информационных технологий и существенным повышением роли практических и самостоятельных занятий. Достоинство предлагаемых подходов заключается в их универсальности: при определенной адаптации они могут быть использованы для обучения другим дисциплинам независимо от специфики и вида образовательного учреждени

PROBLEMS OF IT DEPARTMENT IN A MEDICAL UNIVERSITY

The aim of the study is the analysis of the problems faced by heads and staff of IT departments in medical universities. Methodology and research methods. The methods involve expert estimation, analysis and generalization of practical work experience of IT departments. Results and scientific novelty. The main aspects and specifics of professional activity of IT departments of modern medical schools are designated. The approaches to the definition of the hierarchy of goals in the professional activities of the department, as well as quantitative and qualitative indicators that assess the effectiveness of their achievements are analyzed. The contradictions arising between long-term and short-term goals of the IT department are highlighted. The main challenges which heads of IT departments can deal with in the course of day-to-day management work planning are described. The problems arising in educational, educational-methodical and scientific work of department, in its economic activity, solution of personnel affairs, and aspects of material support are considered. The possible solutions to these problems are proposed. Practical significance. The results of the analysis, proposed approaches and practical recommendations will enable to better organize the work of the IT department in a medical school. The advantage of the proposed approaches consists in their versatility: with some adjustment, they can be used by other departments, regardless of the specifics and the type of educational institution.Цель статьи - проанализировать типичные проблемы, с которыми сталкиваются руководители и коллективы кафедр информационных технологий в медицинских вузах. Методики. В ходе работы использовались экспертная оценка, анализ и обобщение опыта деятельности кафедр информационных технологий. Результаты и научная новизна. Обозначены основные аспекты и специфика профессиональной деятельности кафедры информационных технологий современного медицинского вуза. Намечены подходы к определению иерархии целей данной деятельности, а также количественных и качественных показателей оценки результативности их достижения. Показаны противоречия, возникающие между долгосрочными и краткосрочными целями развития кафедры. Описаны основные трудности, с которыми сталкивается руководитель кафедры при планировании текущей работы. Рассмотрены проблемы, возникающие в учебной, учебно-методической и научной работе кафедры, в ее экономической деятельности, решении кадровых вопросов и вопросов материально-технического обеспечения. Предложены возможные пути нивелирования выявленных проблем. Практическая значимость. Сформулированы практические рекомендации по более эффективной организации работы кафедры информационных технологий в медицинском вузе. Достоинство рекомендаций заключается в их универсальности: при определенной адаптации они могут быть использованы другими кафедрами независимо от их профиля и вида образовательного учреждения

TEACHING MATHEMATICAL DISCIPLINES AT THE MEDICAL UNIVERSITY

Introduction. In programs of training of students of medical specialties, Mathematics is a subject of basic education, i.e. non-core discipline. However, studying Mathematics is extremely important for future physicians, as recently there has been an impetuous development of mathematization in the field of health care. Today, a set of the new medical devices, the equipment and high technologies are being developed based on the mathematical modeling, analysis and forecasting. Mathematical methods are widely applied to diagnostics, development of life-support systems and the description of various biological processes both at the molecular level,  and at the level of a whole organism, its systems, bodies and tissues. The solution of many medical tasks in the field of taxonomy, genetics, and organization of medical service is impossible without knowledge of mathematics. Unfortunately, along with the evident importance of mathematical preparation for a medical profession, its need is poorly realized not only by junior students, but even by some teachers of specialized departments of medical schools. The aim of the publication is to discuss the problems that arise in the teaching of mathematical disciplines to students at a medical school and to suggest possible solutions to these problems. Methodology and research methods. The study is based on the use of modeling of the educational process. The methods of analysis, generalization and the method of expert assessments were applied in the course of the research. Results and scientific novelty. The aspects of mathematical preparation at the university are considered on the basis of the application of the multiplicative model of training quality. It is shown that the main students’ learning difficulties in Mathematics are connected with the following factors: the initial level of mathematical preparation of students and their motivation; outdated methods of Mathematics teaching and academic content designing which is being complicated by existing imbalance between the amount of training material and time frame for its studying. The authors suppose that it is possible to improve the quality of education through the increase or redistribution of the number of teaching hours; stimulation students’ motivation; enhancement of content and methodical components of teaching by means of active use of electronic resources and information technologies. Teachers should aspire to avoid excessive mathematical formalism as well to form in students the skills of independent work through the use of mathematical and computer methods. Practical significance. The authors come to the conclusion that the transition from traditional teaching to the teaching through the technological application of mathematical methods in medical practice and independent conduction of medical research is required for improvement the quality of Mathematics teaching of future physicians. Введение. В программах подготовки студентов медицинских специальностей математика является предметом базового образования, т. е. непрофильной дисциплиной. Однако ее изучение крайне важно для будущих врачей, так как в последнее время происходит стремительная математизация области здравоохранения. Появляется множество новых медицинских приборов, техники и высоких технологий, основанных на математическом моделировании, анализе и прогнозировании. Математические методы широко применяются для диагностики, разработок систем жизнеобеспечения и описания различных биологических процессов как на молекулярном уровне, так и на уровне целостного организма, его систем, органов и тканей. Без знания математики невозможно решение многих медицинских задач в областях таксономии, генетики, организации медицинской службы. К сожалению, при всей очевидной значимости математической подготовки для профессии врача ее необходимость слабо осознается не только студентами младших курсов, но и некоторыми преподавателями специализированных кафедр медицинских вузов. Цель публикации – обсуждение проблем, возникающих при преподавании математики в медицинском университете, и возможных путей их решения. Методология и методики. Представленная в статье работа основана на моделировании учебного процесса. В ходе исследования использовались методы анализа, обобщения и метод экспертных оценок. Результаты и научная новизна. Аспекты математической подготовки в медицинском вузе рассмотрены на основе универсальной мультипликативной модели качества обучения. Показано, что основные трудности освоения студентами программ математических дисциплин связаны с такими факторами, как низкий исходный (школьный) уровень математических знаний учащихся, их мотивация к обучению, во многом устаревшие методики преподавания математики и содержание курсов, формирование которого осложняется существующим дисбалансом между объемом учебного материала и временем, предусмотренным для его изучения. Повысить качество обучения, с точки зрения авторов, можно за счет увеличения или перераспределения учебных часов, стимулирования мотивации студентов, совершенствования содержательной и методической компонент преподавания посредством активного привлечения электронных ресурсов и использования информационных технологий. Преподавателям следует избегать излишнего математического формализма и стремиться к формированию у студентов навыков самостоятельной работы с помощью математико-компьютерных методов. Практическая значимость. Резюмируется, что для повышения качества обучения математике будущих врачей требуется переход от классического преподавания дисциплины к обучению способам технологического применения математических методов в медицинской практике и при самостоятельном проведении медицинских исследований

Hidden Markov Models and their Application for Predicting Failure Events

We show how Markov mixed membership models (MMMM) can be used to predict the degradation of assets. We model the degradation path of individual assets, to predict overall failure rates. Instead of a separate distribution for each hidden state, we use hierarchical mixtures of distributions in the exponential family. In our approach the observation distribution of the states is a finite mixture distribution of a small set of (simpler) distributions shared across all states. Using tied-mixture observation distributions offers several advantages. The mixtures act as a regularization for typically very sparse problems, and they reduce the computational effort for the learning algorithm since there are fewer distributions to be found. Using shared mixtures enables sharing of statistical strength between the Markov states and thus transfer learning. We determine for individual assets the trade-off between the risk of failure and extended operating hours by combining a MMMM with a partially observable Markov decision process (POMDP) to dynamically optimize the policy for when and how to maintain the asset.Comment: Will be published in the proceedings of ICCS 2020; @Booklet{EasyChair:3183, author = {Paul Hofmann and Zaid Tashman}, title = {Hidden Markov Models and their Application for Predicting Failure Events}, howpublished = {EasyChair Preprint no. 3183}, year = {EasyChair, 2020}