The parallax distorsion via a weak microlensing effect

Parallax measurements allow distances to celestial objects to be determined. Coupled with measurement of their position on the celestial sphere, it gives a full three-dimensional picture of the location of the objects relative to the observer. The distortion of the parallax value of a remote source affected by a weak microlensing is considered. This means that the weak microlensing leads to distortion of the distance scale. It is shown that the distortions to appear may change strongly the parallax values in case they amount to several microseconds of arc. In particular, at this accuracy many measured values of the parallaxes must be negative.Comment: 34 LaTeX pages, 12 PostScript figure (epsfig.sty

Microarcsecond instability of the celestial reference frame

The fluctuation of the angular positions of reference extragalactic radio and optical sources under the influence of the irregular gravitational field of visible Galactic stars is considered. It is shown that these angular fluctuations range from a few up to hundreds of microarcseconds. This leads to a small rotation of the celestial reference frame. The nondiagonal coefficients of the rotation matrix are of the order of a microarcsecond. The temporal variation of these coefficients due to the proper motion of the foreground stars is of the order of one microsecond per 20 years. Therefore, the celestial reference frame can be considered inertial and homogeneous only to microarcsecond accuracy. Astrometric catalogues with microarcsecond accuracy will be unstable, and must be reestablished every 20 years.Comment: 5 pages, 2 figures, accepted to MNRA

Звуковой барьер как фактор внешнего воздействия на механические системы навигационной аппаратуры

Проаналізовано режим розповсюдження акустичного випромінювання високої інтенсивності, вище 180 дБ, при подоланні літальними апаратами звукового бар’єру, що супроводжується звуковим ударом (хлопком), окреслена структура і фізико-механічні характеристики явища. Введено нове поняття «хлопка» як зовнішнього збурюючого чиннику впливу на прилади та системи командно-вимірювального комплексу рухомих об’єктів. Будується розрахункова модель пружної взаємодії акустичного удару з бортовою апаратурою літальних апаратів. З’ясовується ступінь впливу акустичної хвилі на пілотажно-навігаційне обладнання з метою встановлення природи дії ударної хвилі та визначення шляхів ефективного нівелювання цього впливу. Звертається увага на найбільш уразливий елемент інерціальних приладів – підвіс гіроскопа, пружно-напружений стан якого сприймається за вхідну величину.We consider the mode of propagation acoustic radiation of high intensity, more than 180 dB, when overcoming with aircraft sound barrier, accompanied by a sound blow (slap), outlined the structure and physical-mechanical characteristics of the phenomenon. A new term "slap" as an external disturbing factor effects on devices and systems for command and measurement complex moving objects. We construct a calculation model of elastic interaction of the acoustic impact of aircraft onboard equipment. Turns out the impact of acoustic waves in navigation and flight equipment to determine the nature of the shock wave and identify ways of effectively leveling this influence. Pays attention to the most vulnerable element of inertial devices – suspension of gyroscope, elastic-stress state which is perceived by the input value.Проанализирован режим распространения акустического излучения высокой интенсивности, более 180 дБ, при преодолении летательными аппаратами звукового барьера, сопровождается звуковым ударом (хлопком), приведена структура и физико-механические характеристики явления. Введено понятие «хлопка» как внешнего возмущающего фактора влияния на приборы и системы командно-измерительного комплекса движущихся объектов. Строится расчетная модель упругого взаимодействия акустического удара с бортовой аппаратурой летательных аппаратов. Определяется степень влияния акустической волны на пилотажно-навигационное оборудование с целью установления природы воздействия ударной волны и определение путей эффективного нивелирования этого влияния. Обращается внимание на наиболее чувствительный элемент инерциальных приборов – подвес гироскопа, упруго-напряженное состояние которого, воспринимается как входная величина

Are Sanctions on Offenses Against Objects of Flora and Fauna Perfect?

The article draws attention to the shortcomings of the construction of sanctions rules on crimes that infringe on the objects of flora and fauna. Taking into account the nature and degree of public danger, the acts of this group are classified by the legislator as crimes of small, medium gravity and serious crimes. The severity of the criminal act is indicated by the sanction of the criminal law norm. The analysis of the sanctions of this group of criminal acts showed that their design is far from perfect. The drawbacks are obvious both in the construction of single and alternative sanctions, as well as sanctions with an additional type of punishment. For example, when designing appropriate sanctions, the legislator equally often uses a fine and imprisonment; sanctions of the rules on crimes that infringe on flora and fauna are not all alternative; the degree of alternative is manifested in different ways; there is diversity in the legislator’s approaches to determining the number of additional penalties and their status in the framework of crimes of small gravity, medium gravity and serious crimes, as well as between these categories of criminal acts. According to the author, the legislator does not have clear criteria for designing sanctions, which undoubtedly negatively characterizes the quality of the criminal law in general

Effects of Chronic Oral Administration of Midazolam on Memory and Circadian Rhythms in Rats

Studies have shown the ability of benzodiazepine drugs to cause memory loss in animals and humans. Midazolam is a benzodiazepine commonly administered intravenously during surgical procedures because it reacts rapidly, causes anterograde amnesia, and has few side effects. It has also been used in palliative medicine where, among others, an oral route has been employed for chronic administration of the drug. The current study evaluated the effects of chronic orally administered midazolam on spatial working memory and procedural memory in control and experimental female rats over a threeweek experimental period utilizing the Morris water maze. Sample and test run times to a submerged platform in the maze were recorded daily. In addition, activity wheels attached to each cage were employed to monitor daily circadian activity of the animals. Spatial working memory was not impaired in either group. However, procedural memory amnesia occurred in animals receiving the drug indicative of a consolidation or retrieval problem. Concerning circadian rhythms, a phase-shift was noted in experimental animals possibly indicating that time of day of drug administration is important. The findings of the present study could shed insight into altered reactions observed in humans who have received midazolam as a component of treatment in palliative medicine

The Turks on medieval arab maps : 9th-10th centuries

The Arab medieval maps depict various kinds of Turks. Muḥammad al-Khwārizmī mentioned the Turks and Toguzguz as the population of two Scythias of Ptolemy – the inner and outer sides of the mountain Imaus. However, al-Khwārizmi did not associate the location of Scythia (Askutiya) with this mountain. The circular world maps of al-Balkhī, al-Iṣṭakhrī and Ibn Ḥawqal show the various Turk peoples around Caspian and Aral Seas

International volunteering as a mean of youth development of BRICS countries

В статье представлен ряд положений, сформулированных авторами на основе эмпирических исследований международного студенческого волонтерства, проведенных в 2015–2016 гг. (всероссийский онлайнопрос молодых волонтеров-активистов, глубинные полуформализованные интервью со студентами, имеющими опыт участия в международных волонтерских проектах). По мнению авторов, международное волонтерство реализует важные социальные функции, повышает конкурентоспособность выпускников на рынке труда. В докладе описаны перспективы развития международного волонтерства студентов стран БРИКС, выявлен его потенциал в развитии человеческого капитала молодежи данных стран.The article represents a number of suggestions based on the empirical research of international student volunteering held in 2015–2016 (Russian online poll of young volunteers, activists, in-depth interviews with students who have experience of participation in international volunteer projects). According to the authors, the international volunteering implements important social functions for students, improves their competitiveness in the labor market. The article suggests the prospects for the development of international volunteering students of BRICS countries, describes its potential in the development of the human capital of young people.Статья написана при поддержке РГНФ, проект № 16-03-00016 «Динамика российского волонтерства: перспективные практики, проблемы и возможности управления»

Ocean loading effects from tidal tilt observations in Lanzarote Island

Comunicación presntada a la 3ª Asamblea Hispano-Portuguesa de Geodesia y Geofísica = 3ª Assembleia Luso-Espanhola de Geodesia e Geofisica, celebrada en Valencia entre el 4 y el 8 de febrero de 2002.Since 1995 two short base-length horizontal pendulums are continuously recording at the station Cueva de los Verdes (Geodynamics laboratory of Lanzarote). Both tilt-meters are modified from the classical Ostrovsky pendulums and are adapted to the local features of the station. The tilt-meters have a working range of measurements of +-20seconds of arc and can resolve up to one second of arc. Such technical properties allow determining the precise tilt response to Earth tides. The tidal tilt models obtained show an important influence from ocean tides. Thus, the estimated amplitude for the main harmonic constituents is of some 4-5 times larger than values measured at continental stations. In this work, the ocean loading and attraction effect, which are computed from global ocean tidal models supplemented with precise regional and local ones will be evaluated. Hence, tidal tilt observations can be corrected from this effect.Peer reviewe

Pivoting of microtubules driven by minus-end-directed motors leads to spindle assembly

Background At the beginning of mitosis, the cell forms a spindle made of microtubules and associated proteins to segregate chromosomes. An important part of spindle architecture is a set of antiparallel microtubule bundles connecting the spindle poles. A key question is how microtubules extending at arbitrary angles form an antiparallel interpolar bundle. Results Here, we show in fission yeast that microtubules meet at an oblique angle and subsequently rotate into antiparallel alignment. Our live- cell imaging approach provides a direct observation of interpolar bundle formation. By combining experiments with theory, we show that microtubules from each pole search for those from the opposite pole by performing random angular movement. Upon contact, two microtubules slide sideways along each other in a directed manner towards the antiparallel configuration. We introduce the contour length of microtubules as a measure of activity of motors that drive microtubule sliding, which we used together with observation of Cut7/kinesin-5 motors and our theory to reveal the minus-end- directed motility of this motor in vivo. Conclusion Random rotational motion helps microtubules from the opposite poles to find each other and subsequent accumulation of motors allows them to generate forces that drive interpolar bundle formation

Formation of Anthropometric, Functional and Psychophysiological Indicators in Students of Medical Colleges under the Influence of Physical Activity

Purpose: to define the dynamics of physical development indicators among medical college students in 2017 and to compare it with the results of the previous study of 2005. Method: The inclusion criteria were: no health complaints at the time of the examination, no chronic diseases in family medical history, no deviations from the norm in clinical and laboratory tests. The selected young men were examined by medical specialists (neuropathologist, ophthalmologist, otolaryngologist, therapist, surgeon); detailed clinical, laboratory and diagnostic tests were conducted: X-ray; spirography; electrocardiography; dental examination; ultrasound examination (cardiovascular, thyroid, abdominal, urological); biochemical blood testing. The participants were subdivided into two groups: Group 1 (students (n=140) who studied at Zhytomyr Medical College in 2004-2005) and Group 2 (students (n=150) who studied at Zhytomyr Medical Institute in 2016-2017). Results: According to the results of studying the dynamics of anthropometric, functional and psychophysiological indicators of physical development among Ukrainian medical college students (n=290; 17-21 years old) in 2017, comparing them with the results of the previous study, conducted in 2005, the tendency to gain in body mass in average values from (0.88 ± 0.26) to (2.7 ± 0.67), in body mass index from (0.88 ± 0.26) to (1.38 ± 0.38), in the fat component from (8.70 ± 0.22) to (9.36 ± 0.21) was established. Conclusions: An increase in body mass index, the fat component in medical college students was revealed, which is related to problems in the quality of the students' diet. Though the muscle mass has increased, and the study indicates that there is insufficient physical activity; sustainability and concentration of attention indicators tend to decrease under the influence of intensification of the educational process. The dynamics of the indicators under analysis indicates the stabilization of the growth process in Ukrainian male students