Neutron reflection from the liquid helium surface.

The reflection of neutrons from a helium surface has been observed for the first time. The 4He surface is smoother in the superfluid state at 1.54 K than in the case of the normal liquid at 2.3 K. In the superfluid state we also observe a surface layer ~200 Å thick which has a subtly different neutron scattering cross-section, which may be explained by an enhanced Bose-Einstein condensate fraction close to the helium surface. The application of neutron reflectometry described in this paper creates new and exciting opportunities for the surface and interfacial study of quantum fluids

Influence of the liquid helium meniscus on neutron reflectometry data

Neutron reflectometry offers a unique opportunity for the direct observation of nano-stratification in 3He-4He mixtures in the ultra-low temperature limit. Unfortunately the results of recent experiments could not be well-modelled on account of a seemingly anomalous variation of reflectivity with momentum transfer. We now hypothesize that this effect is attributable to an optical distortion caused by the liquid’s meniscus near the container wall. The validity of this idea is tested and confirmed through a subsidiary experiment on a D2O sample, showing that the meniscus can significantly distort results if the beam size in the horizontal plane is comparable with, or bigger than, the diameter of the container. The meniscus problem can be eliminated if the beam size is substantially smaller than the diameter of the container, such that reflection takes place only from the flat region of the liquid surface thus excluding the meniscus tails. Practical measures for minimising the meniscus distortion effect are discussed

Plasma dispersion of multisubband electron systems over liquid helium

Density-density response functions are evaluated for nondegenerate multisubband electron systems in the random-phase approximation for arbitrary wave number and subband index. We consider both quasi-two-dimensional and quasi-one- dimensional systems for electrons confined to the surface of liquid helium. The dispersion relations of longitudinal intrasubband and transverse intersubband modes are calculated at low temperatures and for long wavelengths. We discuss the effects of screening and two-subband occupancy on the plasmon spectrum. The characteristic absorption edge of the intersubband modes is shifted relatively to the single-particle intersubband separation and the depolarization shift correction can be significant at high electron densities

Polaron effects in electron channels on a helium film

Using the Feynman path-integral formalism we study the polaron effects in quantum wires above a liquid helium film. The electron interacts with two-dimensional (2D) surface phonons, i.e. ripplons, and is confined in one dimension (1D) by an harmonic potential. The obtained results are valid for arbitrary temperature ($T$), electron-phonon coupling strength ($\alpha$), and lateral confinement ($\omega_{0}$). Analytical and numerical results are obtained for limiting cases of $T$, $\alpha$, and $\omega_{0}$. We found the surprising result that reducing the electron motion from 2D to quasi-1D makes the self-trapping transition more continuous.Comment: 6 pages, 7 figures, submitted to Phys. Rev.

Mission of journalism: motives of evolution

В статье рассматривается феномен миссии журналистики в современной ее трактовке, адекватной специфике постиндустриального общества. Характеризуются два контрарных типа существования и функционирования массмедиа — медиарежим и медиарынок. Обозначаются две парадигмы журналистской деятельности, соответствующие режимным и рыночным свойствам инфосреды. Определяются мутации миссии журналистики при переходе из медиарежима в медиарынок.The article reviews the phenomenon of journalism mission in its modern interpretation, which corresponds with the postindustrial society’s specifics. Two contrasting types of existence and functioning of mass media are described: the media regime and the media market. Two paradigms of journalistic activity, relevant in terms of the regime and market characteristics of the info&sphere, are presented. The mutations of the journalism mission are defined while moving from the media regime to the media market

Modern Press in New Media Sphere

В постиндустриальном обществе существенно трансформируется духовно-практическая отрасль социального воспроизводства. Быстро осуществляется диверсификация инструментального арсенала информационно-вещательной сферы социума. Основательно мутирует в информационном обществе журналистика как профессиональная деятельность и система массмедиа. Модернизируется современная пресса: идеологически (содержательно) – от информатора к интегратору, координатору, регулятору общественной жизни и технологически (формально) – от печатно-электронного контента к цифровому аналогу. Меняются юридические «правила игры» в традиционном и инновационном медиапространстве.The spiritual and practical branch of social reproduction is significantly transformed in the post-industrial society. The diversification of the instrumental arsenal of the information and broadcasting sphere of society is quickly implemented. Journalism as a professional activity and mass media system is fundamentally mutating in the information society. Modern press is being modernized: ideologically (in content) – from an informant to an integrator, coordinator, regulator of public life, and technologically (formally) - from printed and online content to a digital analog. Legal «rules of the game» are changing in traditional and innovative media space

Trends of Disposition «Authorities - Press»

В статье рассматриваются причинно-следственные механизмы социально-политического симбиоза власти и прессы. Устанавливается зависимость характера атмосферы в обществе от контактности структур политики и журналистики. Выявляется российская специфика глобальной диспозиции «власть — пресса» в связи с возможностью государственного учредительства СМИ. Выделяются сравнительно-типологическим методом виды отношений власти и прессы — апологетика, антагонистика, конструктивистика. Характеризуются тренды развития общества на основе конструктивного взаимодействия власти и прессы.The article analyzes the cause-and-effect mechanisms of the socio-political symbiosis of authorities and press. The dependence of the nature of the public sentiment from the in-touch capabilities of politics and journalism structures is identified. The Russian specificity of the global disposition between authorities and press is revealed in connection with the possibility of the governmental foundation of mass media. The types of relations between authorities and press — apologetics, antagonistics, constructivistics — are marked out by the comparative-typological method. The development trends of society are characterized on the basis of constructive interaction between authorities and press

Long-Term Oscillations of Sunspots and a Special Class of Artifacts in SOHO(MDI) and SDO(HMI) Data

A specific type of artifacts, that originate due to displacement of the image of a moving object along the digital (pixel) matrix of receiver are analyzed in detail. The criteria of appearance and the influence of these artifacts on the study of long-term oscillations of sunspots are deduced. The obtained criteria suggest us methods for reduction or even elimination of these artifacts. It is shown that the use of integral parameters can be very effective against the artifact distortions. The simultaneous observations of sunspot magnetic field and ultraviolet intensity of the umbra have given the same periods for the long-term oscillations. In this way the real physical nature of the oscillatory process, which is independent of the artifacts have been confirmed again. A number of examples considered here confirm the dependence between the periods of main mode of the sunspot magnetic field long-term oscillations and its strength. The dependence was derived earlier from both the observations and the theoretical model of the shallow sunspot. The anti-phase behavior of time variations of sunspot umbra area and magnetic field of the sunspot demonstrates that the umbra of sunspot moves in long-term oscillations as a whole: all its points oscillate with the same phase.Comment: 25 pages, 12 figure

Риск-адаптированный подход к скринингу рака предстательной железы

Mass prostatic specific antigen (PSA) testing (population-based PSA screening) has remained controversial, nevertheless there are men cohorts likely to benefit from PSA screening. Heritable factors contribute to 60 % risk for developing familial prostate cancer. Despite the fact that its clinical application is challenging due to polygenic inheritance, advances in new generation sequencing technologies permit identifying highly penetrant germline mutations in genes BRCA1, BRCA2, CHEK2, HOXB13 and MMR associated with tremendous increase in risk of developing the prostate cancer. Several germline mutations are associated with clinically aggressiveness of disease and shortened survival. Targeted screening that is based on family history and genomic aberrations should be the next step towards the precision medicine. Men at elevated risk should been performed for early detection are those with familiar history of prostate cancer, or BRCA1, BRCA2, CHEK2, HOXB13 and MMR pathogenic germline mutation carriers, or first line relatives diagnosed with certain types of cancer. Systematic PSA testing in 1–2 years among germline mutation carriers men beginning at age 45 years would contribute to increase in early detection of localized prostate cancer resulting in more chance of curative treatment and improve survival ratesОстается неоднозначным вопрос целесообразности ПСА-тестирования у всего мужского населения (популяционный ПСА-скрининг), однако есть категории мужчин, для которых скрининг рака предстательной железы дает очевидные преимущества. Наследуемые факторы обусловливают до 60% риска развития РПЖ. Основным препятствием для применения в клинической практике остается смешанный тип наследования, однако с применением технологий секвенирования нового поколения стала доступна детекция высокопенетрантных герминальных мутаций в генах BRCA1, BRCA2, MMR, HOXB13 и CHEK2, многократно повышающих риск заболевания, часть из которых ассоциированна с агрессивным течением болезни и короткой продолжительностью жизни. Направленный скрининг с учетом семейного анамнеза и геномной информации должен стать следующим шагом в направлении прецизионной медицины. Группы риска для ранней диагностики должны включать  мужчин как с семейными формами РПЖ, так и носителей герминальных мутаций в генах BRCA1, BRCA2, CHEK2, HOXB13 или MMR, а также тех, чьи кровные родственники первой линии страдали некоторыми злокачественными опухолями. Регулярное ПСА-тестирование с интервалом 1-2 года начиная с возраста 45 лет у мужчин, имеющих вышеуказанные мутации, приведет к большей выявляемости РПЖ на ранних стадиях, что даст возможность проведения куративного лечения и таким образом повысить выживаемость больных

О стадировании онкоурологических заболеваний по обновленной TNM-классификации 8-го издания

On January 1, 2018, an updated 8th edition of the international TNM Classification of Malignant Tumors comes into effect. The classification was developed by 2 leading organizations: the American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC). Based on consensus conferences of the International Society for Urological Pathology (ISUP) which reconsidered the current approaches to pathomorphology and staging of malignant tumors of the prostate (2009), kidneys (2012), testicles and penis (2015), the World Health Organization approved the new morphological classification of tumors of the urinary and male reproductive systems. At the first time, the TNM Classification indicates evidence level.С 1 января 2018 г. вступает в силу действие обновленной международной TNM-классификации злокачественных опухолей 8-го издания, созданной 2 ведущими организациями: Американским объединенным комитетом по изучению рака (AJCC) и Международным противораковым союзом (UICC). На основании консенсусных конференций Международного общества уропатологов (ISUP), пересмотревших текущие подходы к патоморфологии и стадированию злокачественных опухолей предстательной железы (2009 г.), почек (2012 г.), яичек и полового члена (2015 г.), Всемирной организацией здравоохранения утверждена современная морфологическая классификация опухолей мочевыделительной и мужской половой систем. Впервые в TNM-классификации указан уровень доказательности