111 research outputs found
Results of the study of the vestibular apparatus and the functions of the perception of space in cosmonauts (pre- and post-flight observations)
The effect of the set of space flight factors caused a change in the activity of the vestibular apparatus and the spatial perception function. More significant and longer shifts were observed during expeditions of great duration. The detected disorders (increase in reactivity of the otolithic apparatus, decrease in sensitivity of the cupula receptor, deterioration in the perception accuracy, etc.) had a definite tendency to be restored. The primary damage to the otolithic reflex (changes were found in practically all the subjects) is probably caused by the specific effect of zero gravitation, and apparently, may be one of the trigger mechanisms for discrepancy in the activity of the sensory systems, disorders in the correcting function of the cerebellum, and central vestibular formations
Towards the electron EDM search. Theoretical study of PbF
We report ab initio relativistic correlation calculations of potential curves
and spectroscopic constants for four lowest-lying electronic states of the lead
monofluoride. We also calculated parameters of the spin-rotational Hamiltonian
for the ground and the first excited states including P,T-odd and P-odd terms.
In particular, we have obtained hyperfine constants of the Pb nucleus.
For the state MHz, MHz and for
the A MHz, MHz. Our values of
the ground state hyperfine constants are in good agreement with the previous
theoretical studies. We discuss and explain seeming disagreement in the sign of
the constant with the recent experimental data. The effective
electric field on the electron , which is important for the planned
experiment to search for the electric dipole moment of the electron, is found
to be 3.3 * 10^{10} V/cm
Big Challenges in the History of Imperial Russia: Civilisational and Geopolitical Dimensions
The article was submitted on 19.02.2017.This article is devoted to one of the most complicated issues of Russian history, i. e. the challenges of modernity, which are viewed through the prism of the concept of modernisation (used to describe the transition from a traditional agrarian society to an industrial and urban one). A historical challenge is a complex category, not a simple action “to spite the arrogant neighbour”. One of the main reasons for its emergence is technological revolutions that fundamentally change the conditions of human communities. Typologies of challenges vary from natural and climatic to social and political. Russia has come across many of them. Civilisational, geopolitical, technological, socio-political, cultural, and ideological challenges are the most typical of the imperial period. Their research discusses the characteristics of the essence of a challenge, the need to understand it, respond to it, the struggle of opinions about the reaction to them, and the evaluation of the results achieved. As an example of this approach, the authors consider two of the aforementioned challenges. In Russian historiography, the concept of “challenges” is not uncommon, but quite often the reaction to them did not take into account the dynamics of modernisation. The method put forward by the authors, based on the “challenges and responses” scheme, makes it possible to bridge this gap and provides practically meaningful results without them being ready-made recipes. Preliminary conclusions about two of the indicated challenges demonstrate that they were only slowly understood by the Russian ruling elite, which resulted in the cataclysms of the First World War and the Revolution of 1917 that put Russia on the brink of a civilisational catastrophe, although one should not forget that in the course of the period under study the country turned into a power of world significance.Вызовы Нового времени в российской истории рассматриваются сквозь призму концепции модернизации – перехода от традиционного аграрного общества к индустриально-урбанизированному. Одна из главных причин возникновения исторических вызовов – технологические революции, принципиально меняющие условия существования человеческих сообществ. Показано, что типология вызовов, с которыми сталкивалась Россия, очень разнообразна – от природно-климатических до социально-политических. Наиболее типичными для имперского периода были цивилизационные, геополитические, технологические, социально-политические, культурно-мировоззренческие. Их исследование включает характеристику сущности вызова, необходимость его осознания и возможности ответа, борьбу мнений по поводу ответа, оценку достигнутых результатов. Обращено особое внимание на цивилизационный и геополитический аспекты. В российской историографии понятие «вызовы» не редкость, но ответы на них часто давались без учета модернизационной динамики. Предложенный метод анализа по схеме «вызов – ответ» поможет преодолеть такую ситуацию и дать практически значимые результаты. Вызовы с опозданием осознавались российской правящей элитой, что и привело в конечном счете к катаклизмам Первой мировой войны и революции 1917 г., поставивших Россию на грань цивилизационной катастрофы. При этом, по мнению авторов, надо оценивать усилия, приложенные населением страны, в результате которых она за рассматриваемый период добилась значительного прогресса, превратившись в державу мировой значимости
Proton acceleration in analytic reconnecting current sheets
Particle acceleration provides an important signature for the magnetic collapse that accompanies a solar flare. Most particle acceleration studies, however, invoke magnetic and electric field models that are analytically convenient rather than solutions of the governing magnetohydrodynamic equations. In this paper a self-consistent magnetic reconnection solution is employed to investigate proton orbits, energy gains, and acceleration timescales for proton acceleration in solar flares. The magnetic field configuration is derived from the analytic reconnection solution of Craig and Henton. For the physically realistic case in which magnetic pressure of the current sheet is limited at small resistivities, the model contains a single free parameter that specifies the shear of the velocity field. It is shown that in the absence of losses, the field produces particle acceleration spectra characteristic of magnetic X-points. Specifically, the energy distribution approximates a power law ~ξ-3/2 nonrelativistically, but steepens slightly at the higher energies. Using realistic values of the “effective” resistivity, we obtain energies and acceleration times that fall within the range of observational data for proton acceleration in the solar corona
Recyclizations of 2-aminobenzylimines and thioaroylhydrazones of N-substituted N-hydroxy-3-oxobutanamides
A universal scheme is proposed for the molecular design of heterocyclic recyclizations by replacing the exocyclic hydroxyl groups in exo-trig- ring-chain tautomeric molecules with substituted amines or hydrazines. The practical applicability of this approach is demonstrated by the condensations of 5-hydroxy-5-methyl-3-isoxazolidinones with thioaroyl-hydrazines and 2-aminomethylaniline. The condensation products were studied by modern 1H, 13C and 15N NMR spectroscopic methods using three solvents: CDCl3, DMSO[D6] and CD3CN. The solvent was found to have a strong effect to the relative amounts of the tautomers
ГОРМОНАЛЬНАЯ ТЕРАПИЯ ПРЕПАРАТОМ ЛЕЙПРОРЕЛИН (ЛЮКРИН-ДЕПО®) У БОЛЬНЫХ РАКОМ ПРЕДСТАТЕЛЬНОЙ ЖЕЛЕЗЫ
Leuproprelin acetate (Lucrin-depot) is an efficacious and safe luteinizing hormone-releasing hormone analogue, the efficiency of which has been proven in a number of large clinical studies. The agent exhibits a sustained release, is easy-to-use and well-tolerated, and causes minimal side effects. Lucrin-depot may be recommended for use as alone and in combination with other hormonal agents in patients with prostate cancer if androgenic deprivation is indicated.Лейпропрелина ацетат (Люкрин-депо) — результативный и безопасный аналог лютеинизирующего гормона рилизинггормона, эффективность которого доказана в ряде крупных клинических исследований. Препарат оказывает пролонгированное действие, удобен в использовании, дает минимальные побочные эффекты и хорошо переносится больными. Люкрин-депо может быть рекомендован для применения в качестве самостоятельной терапии или в комбинации с другими гормональными препаратами у пациентов с раком предстательной железы при наличии показаний к проведению андрогенной депривации
On Nonperturbative Calculations in Quantum Electrodynamics
A new approach to nonperturbative calculations in quantum electrodynamics is
proposed. The approach is based on a regular iteration scheme for solution of
Schwinger-Dyson equations for generating functional of Green functions. The
approach allows one to take into account the gauge invariance conditions (Ward
identities) and to perform the renormalization program. The iteration scheme
can be realized in two versions. The first one ("perturbative vacuum")
corresponds to chain summation in the diagram language. In this version in
four-dimensional theory the non-physical singularity (Landau pole) arises which
leads to the triviality of the renormalized theory. The second version
("nonperturbative vacuum") corresponds to ladder summation and permits one to
make non-perturbative calculations of physical quantities in spite of the
triviality problem. For chiral-symmetrical leading approximation two terms of
the expansion of the first-step vertex function over photon momentum are
calculated. A formula for anomalous magnetic moment is obtained. A problem of
dynamical chiral symmetry breaking (DCSB) is considered, the calculations are
performed for renormalized theory in Minkowsky space. In the strong coupling
region DCSB-solutions arise. For the renormalized theory a DCSB-solution is
also possible in the weak coupling region but with a subsidiary condition on
the value of .Comment: 31 pages, Plain LaTex, no figures. Journal version: some discussion
and refs. are adde
Comparative Analysis of DNA Replication Timing Reveals Conserved Large-Scale Chromosomal Architecture
Recent evidence suggests that the timing of DNA replication is coordinated across megabase-scale domains in metazoan genomes, yet the importance of this aspect of genome organization is unclear. Here we show that replication timing is remarkably conserved between human and mouse, uncovering large regions that may have been governed by similar replication dynamics since these species have diverged. This conservation is both tissue-specific and independent of the genomic G+C content conservation. Moreover, we show that time of replication is globally conserved despite numerous large-scale genome rearrangements. We systematically identify rearrangement fusion points and demonstrate that replication time can be locally diverged at these loci. Conversely, rearrangements are shown to be correlated with early replication and physical chromosomal proximity. These results suggest that large chromosomal domains of coordinated replication are shuffled by evolution while conserving the large-scale nuclear architecture of the genome
ОПРЕДЕЛЕНИЕ ФАКТОРОВ ПРОГНОЗА ЭФФЕКТИВНОСТИ ТЕРАПИИ БЕВАЦИЗУМАБОМ У БОЛЬНЫХ МЕТАСТАТИЧЕСКИМ ПОЧЕЧНО-КЛЕТОЧНЫМ РАКОМ
Background. The design and introduction of novel medicaments into clinical practice has confirmed that it is necessary to search for new prognostic factors to re-evaluate the clinical and biological properties of a tumor and to identify a subgroup of patients who will benefit from drug treatment. An individual approach and personalization of performed therapy will be able to substantially enhance its efficiency.Subjects and methods. Thirty-four oncology and urology research and health care institutions from 8 federal districts of the Russian Federation took part in the investigation. It enrolled 145 metastatic renal-cell cancer patients who had received targeted therapy with a combination of bevacizumab and interferon-α (IFN-α), in whom an objective response (complete or partial regression) or stabilization of tumor foci was recorded during at least 3-month treatment. The main task of the investigation was to estimate the clinical importance of chosen criteria (an interval from the diagnosis to start of treatment; physical activity according to the Karnofsky scale; a history of nephrectomy; the site and number of metastatic foci; the levels of hemoglobin, neutrophils, platelets, calcium, and alkaline phosphatase) as predictors for the efficiency of bevacizumab therapy.Results. The median follow-up was 9 months (interquartile range (IQR) 6–13 months). The duration of treatment varied between 3 to 22 months; the median was 9 months (IQR 6–13 months). Patients with 3-month progression were excluded from the investigation. A complete and partial responses were recorded in 5 (3.4 %) and 19 (13.1 %) patients, respectively; the tumor process was stabilized in 118 (81.4 %) patients. The median duration of response to therapy with a combination of bevacizumab and IFN-α was 7 months (IQR 5–10 months). The progression-free survival was significantly influenced by prognostic factors, such as hemoglobin and neutrophil levels, age, and time from the diagnosis to starting therapy (p < 0.05). A history of nephrectomy had a significant impact on overall survival (p < 0.05).Conclusion. Our findings suggest that a history of nephrectomy and elevated neutrophil and alkaline phosphatase levels affect the efficiency of performed treatment in terms of an objective response to therapy. The factors influencing progression-free survival included the levels of hemoglobin and neutrophils, age, and time to diagnosis to start therapy.Введение. Разработка и внедрение в клиническую практику новых лекарственных агентов подтвердили необходимость в поиске новых факторов прогноза с целью переоценки клинических и биологических свойств опухоли и определения подгруппы больных, которые получат оптимальную пользу от проводимого лекарственного лечения. Индивидуальный подход и персонализация проводимой терапии позволят существенно повысить ее эффективность.Материалы и методы. В исследовании приняли участие 34 научно-исследовательских и лечебно-профилактических учреждения онкологического и урологического профиля из 8 федеральных округов Российской Федерации. В исследование включили 145 больных метастатическим почечно-клеточным раком, получивших таргетную терапию комбинацией препаратов бевацизумаб и интерферон α (ИФН-α), у которых зарегистрировали объективный ответ (полная регрессия, частичная регрессия) или стабилизация опухолевых очагов за период лечения не менее 3 мес. Основная задача исследования – определение клинической значимости выбранных критериев (интервал от момента установления диагноза до начала лечения, статус физической активности по шкале Карновского, наличие нефрэктомии в анамнезе, локализация и количество метастатических очагов, уровень гемоглобина, нейтрофилов, тромбоцитов, кальция, щелочной фосфатазы) как предикторов эффективности терапии бевацизумабом.Результаты. Медиана времени наблюдения составила 9 мес (интерквартильный размах (IQR) 6–13 мес). Длительность проведения лечения варьировала от 3 до 22 мес, медиана составила 9 мес (IQR 6–13 мес). Больных с прогрессированием в течение 3 мес не включали в исследование. Полный ответ зарегистрировали у 5 (3,4 %) больных, частичный ответ – у 19 (13,1 %) пациентов, стабилизацию опухолевого процесса – у 118 (81,4 %). Медиана длительности ответа на терапию комбинацией препаратов бевацизумаб и ИФН-α составила 7 мес (IQR 5–10 мес). Достоверное влияние на выживаемость без прогрессирования оказывали такие прогностические факторы, как уровень гемоглобина, нейтрофилов, возраст и время от постановки диагноза до начала терапии (p < 0,05). Достоверное влияние на общую выживаемость оказывало наличие в анамнезе нефрэктомии (p < 0,05).Заключение. Согласно нашим данным на эффективность проводимого лечения по уровню объективного ответа на терапию влияют: наличие нефрэктомии в анамнезе, повышенный уровень нейтрофилов и щелочной фосфатазы. К факторам, влияющим на выживаемость без прогрессирования, относились уровень гемоглобина, уровень нейтрофилов, возраст и время от постановки диагноза до начала терапии
- …