Formation of Turing structures in catalytic surface reactions: The facetting of Pt(110) in CO+O₂

The Pt(110) surface facets during the catalytic oxidation of CO, if reaction conditions are adjusted such that the CO‐induced 1×1⇄1×2 phase transition can take place simultaneously. A detailed low‐energy electron diffraction beam profile analysis revealed that regularly spaced (430) and (340) facets are formed with a lateral periodicity of ∼70 lattice units along the [11̄0] direction. This result, together with the observation that the facetted surface is only stable under reaction conditions, indicates a dissipative structure of the Turing type. Such structures, which are stationary but exhibit a periodic variation of the concentration variables in space, have so far almost exclusively been discussed theoretically. The interpretation of the facetted surface as a Turing structure could be confirmed by a Monte Carlo simulation based on the Langmuir Hinshelwood mechanism of catalytic CO oxidation and the CO‐induced 1×1⇄1×2 phase transition

Rigidity analysis of HIV-1 protease

We present a rigidity analysis on a large number of X-ray crystal structures of the enzyme HIV-1 protease using the 'pebble game' algorithm of the software FIRST. We find that although the rigidity profile remains similar across a comprehensive set of high resolution structures, the profile changes significantly in the presence of an inhibitor. Our study shows that the action of the inhibitors is to restrict the flexibility of the beta-hairpin flaps which allow access to the active site. The results are discussed in the context of full molecular dynamics simulations as well as data from NMR experiments.Comment: 4 pages, 3 figures. Conference proceedings for CMMP conference 2010 which was held at the University of Warwic

Educational profession-oriented propaedeutic Russian language course as a basis of coming of international students of pre-university training stage into the educational medium of the higher medical institution

Цель статьи - рассмотреть некоторые способы и методы (фреймовый подход) формирования лингвокультурологической медицинской компетенции иностранных учащихся предвузовского этапа на занятиях по русскому языку общелитературного стиля в соответствии со спецификой их будущего обучения в русскоязычной среде медицинского вуза. Актуальность исследования заключается в том, что учебный пропедевтический курс русского языка, ориентированный на изучение иностранными учащимися языка медицинской науки, является важнейшим и необходимым условием для их обучения в медицинском университете. Преподавание основывается на использовании общедидактических и методических принципов начального обучения русскому языку будущих студентов- медиков, которые способствуют дальнейшему усвоению и совершенствованию учебно- профессиональных знаний в условиях русской языковой среды медицинского вуза. В процессе исследования были использованы следующие методы: теоретический и практический анализ научной литературы по методике преподавания иностранного языка и русского как иностранного, аудиовизуальное наблюдение, беседы с иностранными студентами, пробное обучение. Результаты. В процессе изучения русского языка иностранные учащиеся приобретают новые знания, расширяется их эрудиция, кругозор. Иностранные учащиеся предвузовского этапа входят в мир языка медицинской науки, знакомясь с элементами её лингвистической, коммуникативной и культурологической базы. Выводы: пропедевтический курс русского языка закладывает основы знаний о специфике изучения медицины на русском языке, которые помогут иностранным учащимся предвузовского этапа подготовки спустя год войти в образовательную среду медицинского университета.The aim of the research is to consider some ways and methods (frame approach) of forming lingual- cultural medical competence of international students of pre-University training stage at the Russian Language classes in accordance with the specifics of their future learning in Russian-speaking medium of higher medical institution. Relevance of the study lies in the fact that educational propaedeutic course of the Russian Language, focused on training foreign students the language of medical science, is the most important and necessary condition for their studying in the medical university. Training is based on the usage of general didactic and methodical principles of elementary level of teaching Russian the future medical students, which promoting further learning and mastering the educational-professional knowledge in the conditions of Russian speaking environment of higher medical institution. The author has used the following methods: theoretical and practical analysis of scientific literature on methods of teaching foreign language and Russian as a foreign language, audio-visual monitoring, interviews with foreign students, experimental teaching. Results. When learning Russian the international students get knowledge, enlarge their erudition, the outlook. International students of pre-University training stage come into the world of the Language of medical science, becoming acquainted with the elements of its linguistic, communicative and cultural base. Conclusion. The propaedeutic course of Russian lays foundations of knowledge of specifics of learning medicine in Russian, which will help international students of pre-university training stage to be admitted to the educational environment of medical University after the first year of studying

Adsorption induced reconstruction of the Cu(110) surface

The formation of the O/Cu(110)-(2 × 1) and H/Cu(110)-(1 × 2) superstructures has been investigated by a LEED beam profile analysis. The oxygen induced reconstruction proceeds at later stages by creation of holes on flat terraces. This could not be observed at the hydrogen induced missing row reconstruction. The formation of the missing row structure proceeds most probably via nucleation at steps and subsequent growth of (1 × 2) islands. The influence of different distributions of steps and islands on beam profiles is discussed

Trauma Immediately Preceding REM-Behavior Disorder:A Valuable Prognostic Marker?

Background: The definition of rapid eye movement (REM) sleep behavior disorder (RBD) has varied over the years. Rapid eye movement sleep behavior disorder can be considered isolated or idiopathic or can occur in the context of other disorders, including trauma-associated sleep disorder (TSD) and overlap parasomnia. However, whether trauma in RBD carries any prognostic specificity is currently unknown. Study Objectives: To test the hypothesis that RBD secondary to trauma is less likely to result in the development of neurodegeneration compared to idiopathic RBD (iRBD) without trauma in the general population. Methods: A retrospective cohort study of 122 consecutive RBD patients (103 males) at two tertiary sleep clinics in Europe between 2005 and 2020 was studied. Patients were diagnosed as having iRBD by video polysomnography (vPSG) and had a semi-structured interview at presentation, including specifically eliciting any history of trauma. Patients with secondary RBD to recognized causes were excluded from the study. Patients with iRBD were categorized into three groups according to reported trauma history: (1) No history of trauma, (2) traumatic experience at least 12 months prior to RBD symptom onset, and (3) traumatic experience within 12 months of RBD symptom onset. Idiopathic RBD duration was defined as the interval between estimated onset of RBD symptoms and last hospital visit or death. Follow-up duration was defined as the interval between iRBD diagnosis and last hospital visit or death. Results: In a follow-up period of up to 18 years, no patient who experienced trauma within 12 months preceding their iRBD diagnosis received a diagnosis of a neurodegenerative disorder (n = 35), whereas 38% of patients without trauma within the 12 months of symptom onset developed a neurodegenerative illness. These patients were also significantly more likely to have a family history of α-synucleinopathy or tauopathy. Conclusions: The development of RBD within 12 months of experiencing a traumatic life event, indistinguishable clinically from iRBD, did not lead to phenoconversion to a neurodegenerative disorder even after 18 years (mean follow up 6 years). We suggest that a sub-type of RBD be established and classified as secondary RBD due to trauma. Additionally, we advocate that a thorough psychological and trauma history be undertaken in all patients presenting with dream enactment behaviors (DEB)

Исследование реологических свойств растворов ксантановой смолы и крахмала для оценки межмолекулярного взаимодействия данных реагентов в биополимерных буровых растворах

Работа направленна на разработку систем биополимерных растворов для бурения горизонтальных участков скважин с повышенной эффективностью очистки ствола.The work is aimed to develope systems of biopolymer drilling fluids for horizontal drilling with increased efficiency of wellbore cleaning

Two-domains bulklike Fermi surface of Ag films deposited onto Si(111)-(7x7)

Thick metallic silver films have been deposited onto Si(111)-(7x7) substrates at room temperature. Their electronic properties have been studied by using angle resolved photoelectron spectroscopy (ARPES). In addition to the electronic band dispersion along the high-symmetry directions, the Fermi surface topology of the grown films has been investigated. Using ARPES, the spectral weight distribution at the Fermi level throughout large portions of the reciprocal space has been determined at particular perpendicular electron-momentum values. Systematically, the contours of the Fermi surface of these films reflected a sixfold symmetry instead of the threefold symmetry of Ag single crystal. This loss of symmetry has been attributed to the fact that these films appear to be composed by two sets of domains rotated 60$^o$ from each other. Extra, photoemission features at the Fermi level were also detected, which have been attributed to the presence of surface states and \textit{sp}-quantum states. The dimensionality of the Fermi surface of these films has been analyzed studying the dependence of the Fermi surface contours with the incident photon energy. The behavior of these contours measured at particular points along the Ag $\Gamma$L high-symmetry direction puts forward the three-dimensional character of the electronic structure of the films investigated.Comment: 10 pages, 12 figures, submitted to Physical Review