Statistical anisotropy of CMB as a probe of conformal rolling scenario

Search for the statistical anisotropy in the CMB data is a powerful tool for constraining models of the early Universe. In this paper we focus on the recently proposed cosmological scenario with conformal rolling. We consider two sub-scenarios, one of which involves a long intermediate stage between conformal rolling and conventional hot epoch. Primordial scalar perturbations generated within these sub-scenarios have different direction-dependent power spectra, both characterized by a single parameter h^2. We search for the signatures of this anisotropy in the seven-year WMAP data using quadratic maximum likelihood method, first applied for similar purposes by Hanson and Lewis. We confirm the large quadrupole anisotropy detected in V and W bands, which has been argued to originate from systematic effects rather than from cosmology. We construct an estimator for the parameter h^2. In the case of the sub-scenario with the intermediate stage we set an upper limit h^2 < 0.045 at the 95% confidence level. The constraint on h^2 is much weaker in the case of another sub-scenario, where the intermediate stage is absent.Comment: 27 pages, 4 figures. Stronger constraint in case of sub-scenario A obtained. Version accepted for publication in JCA

Revisiting constraints on (pseudo)conformal Universe with Planck data

We revisit constraints on the (pseudo)conformal Universe from the non-observation of statistical anisotropy in the Planck data. The quadratic maximal likelihood estimator is applied to the Planck temperature maps at frequencies 143 GHz and 217 GHz as well as their cross-correlation. The strongest constraint is obtained in the scenario of the (pseudo)conformal Universe with a long intermediate evolution after conformal symmetry breaking. In terms of the relevant parameter (coupling constant), the limit is h^2 <0.0013 at 95% C.L. (using the cross-estimator). The analogous limit is much weaker in the scenario without the intermediate stage (h^2 \ln \frac{H_0}{\Lambda}<0.52) allowing the coupling constant to be of order one. In the latter case, the non-Gaussianity in the 4-point function appears to be a more promising signature.Comment: 13 pages, 2 figures. Appendix with detailed computation of the Fisher matrix adde

Effect of intermediate Minkowskian evolution on CMB bispectrum

We consider a non-inflationary early Universe scenario in which relevant scalar perturbations get frozen out at some point, but then are defrosted and follow a long nearly Minkowskian evolution before the hot era. This intermediate stage leaves specific imprint on the CMB 3-point function, largely independent of details of microscopic physics. In particular, the CMB bispectrum undergoes oscillations in the multipole l space with roughly constant amplitude. The latter is in contrast to the oscillatory bispectrum enhanced in the flattened triangle limit, as predicted by inflation with non-Bunch--Davies vacuum. Given this and other peculiar features of the bispectrum, stringent constraints imposed by the Planck data may not apply. The CMB 3-point function is suppressed by the inverse duration squared of the Minkowskian evolution, but can be of observable size for relatively short intermediate Minkowskian stage.Comment: 27 pages, 5 figures; references added, representation of the material improved; matches journal versio

Effect of magnetic field on the velocity autocorrelation and the caging of particles in two-dimensional Yukawa liquids

We investigate the effect of an external magnetic field on the velocity autocorrelation function and the "caging" of the particles in a two-dimensional strongly coupled Yukawa liquid, via numerical simulations. The influence of the coupling strength on the position of the dominant peak in the frequency spectrum of the velocity autocorrelation function confirms the onset of a joint effect of the magnetic field and strong correlations at high coupling. Our molecular dynamics simulations quantify the decorrelation of the particles' surroundings - the magnetic field is found to increase significantly the caging time, which reaches values well beyond the timescale of plasma oscillations. The observation of the increased caging time is in accordance with findings that the magnetic field decreases diffusion in similar systems

Integrated model of stochastic dynamics for control of a socio-ecological-oriented innovation economy

On the basis of modern mathematical models, methods and information and technologies, for example, an integrated stochastic nonlinear model of man-made processes and objects, suitable for the conditions of systemic crises, were investigated and developed. Considered in this article are some aspects of integration of a lot of domains and sectors of operation of modern complex systems which are functioning and developing in the present-day conditions of instability, crises and nonlinearity. In order to predict the development of the state of an innovation economy, the nonlinear integrated stochastic model of growthing dynamic in the phase space has been investigated and developed. In the article, problem of the optimization of the management of the activity of modern complex systems that develop and function regarding current conditions of the instability are considered. The prospect of further research based on the developed models is to conduct computer experiments and their practical usisng. The development and study of criterias, methods and models for optimal management of man-made objects and the creation of making decision systems based on the proposed integral models in the state space are also promising

Диагностика и лечение церебрального венозного тромбоза

 BACKGROUND This article is devoted to the discussion of a life-threatening and difficult to diagnose disease — cerebral venous thrombosis (CVT). The article lists clinical manifestations, features of diagnosis and treatment of CVT. Cerebral venous thrombosis is an emergency that requires a quick decision to start therapy in order to prevent the development of venous cerebral infarction, intracranial hemorrhage, severe disability and death. Cerebral venous thrombosis is a rare and rather difficult to recognize form of acute cerebrovascular accident (ACVA). Considering the variability of the clinical and radiological picture, as well as the large number of risk factors, CVT is a complex medical problem. Despite the fact that CVTs account for less than 1% of all ACVA, significant differences in treatment necessitatethe earliest possible differential diagnosis of CVT with arterial stroke. The diagnosis is often made with a delay due to a wide range of clinical manifestations, subacute onset of the disease, as well as low alertness of specialists in relation to CVT. In patients with cryptogenic stroke, CVT should be ruled out as a potential cause of stroke. Among other things, in the case of CVT, as in the case of thrombosis of the cerebral arteries, the establishment of the leading etiological factor is one of the priority tasks, the solution of which allows choosing the optimal means of secondary prevention. AIM OF STUDY Raising awareness of doctors of multidisciplinary hospitals about clinical manifestations, methods of diagnosis and treatment of CVT.MATERIAl AND METHODS To achieve this goal, the results of domestic and foreign scientific research on the diagno-sis and treatment of CVT were analyzed. Literature searches were carried out in electronic search engines Scopus, eLibrary, PubMed using the keywords: cerebral venous thrombosis, cryptogenic stroke, intracerebral hemorrhage, anticoagulant therapy, neurological imaging in cerebral venous thrombosis. For the analysis, scientific articles published between 1828 and 2020 were selected. Thirty percent of the analyzed works on the subject of CVT are not older than 5 years.CONClUSION Due to the various clinical manifestations and the absence of pathognomonic symptoms, neuroimaging plays a leading role in establishing the diagnosis. Early diagnosis of cerebral venous thrombosis and the use of anticoagulants lead to a decrease in disability and mortality.  АКТУАЛЬНОСТЬ    Данная статья посвящена обсуждению жизнеугрожающего и трудно диагностируемого заболевания — церебрального венозного тромбоза (ЦВТ). В статье указаны клинические проявления, особенности диагностики и лечения ЦВТ. Церебральный венозный тромбоз — неотложное состояние, требующее быстрого принятия решения о начале терапии с целью предотвращения развития венозного инфаркта мозга, внутричерепного кровоизлияния, тяжелой инвалидизации и смерти. Церебральные венозные тромбозы являются редкой и достаточно сложно распознаваемой формой острого нарушения мозгового кровообращения (ОНМК). Учитывая вариабельность клинической и радиологической картины, а также большое количество факторов риска, ЦВТ представляют сложную медицинскую задачу. Несмотря на то, что ЦВТ составляют менее 1% от всех ОНМК, значительные различия в лечении обуславливают необходимость максимально ранней дифференциальной диагностики ЦВТ с артериальным инсультом. Диагноз нередко устанавливают с опозданием по причине широкого спектра клинических проявлений, подострого начала заболевания, а также низкой настороженности специалистов в отношении ЦВТ. У пациентов с криптогенным инсультом необходимо исключить ЦВТ как потенциальную причину ОНМК. Помимо всего прочего, в случае ЦВТ, как и при тромбозах церебральных артерий, установление ведущего этиологического фактора является одной из приоритетных задач, решение которой позволяет выбрать оптимальное средство вторичной профилактики. ЦЕЛЬ РАБОТЫ    Повышение информированности врачей многопрофильных стационаров о клинических проявлениях, методах диагностики и лечения ЦВТ. МАТЕРИАЛ И МЕТОДЫ    Для достижения поставленной цели были проанализированы результаты отечественных и зарубежных научных исследований, посвященных диагностике и лечению ЦВТ. Поиск литературы проводили в электронных поисковых системах Scopus, eLibrary, PubMed по ключевым словам: церебральные венозные тромбозы, криптогенный инсульт, внутримозговое кровоизлияние, антикоагулянтная терапия, нейровизуализация при церебральном венозном тромбозе. Для анализа были отобраны научные статьи, опубликованные в период с 1828 по 2020 год. 30% проанализированных работ, посвященных теме ЦВТ, не старше 5 лет. ЗАКЛЮЧЕНИЕ    В связи с различными клиническими проявлениями и отсутствием патогномоничных симптомов, ведущая роль в установлении диагноза принадлежит нейровизуализации. Ранняя диагностика церебрального венозного тромбоза и применение антикоагулянтов приводит к снижению инвалидизации и летальности.

Cluster virial expansion for the equation of state of partially ionized hydrogen plasma

We study the contribution of electron-atom interaction to the equation of state for partially ionized hydrogen plasma using the cluster-virial expansion. For the first time, we use the Beth-Uhlenbeck approach to calculate the second virial coefficient for the electron-atom (bound cluster) pair from the corresponding scattering phase-shifts and binding energies. Experimental scattering cross-sections as well as phase-shifts calculated on the basis of different pseudopotential models are used as an input for the Beth-Uhlenbeck formula. By including Pauli blocking and screening in the phase-shift calculation, we generalize the cluster-virial expansion in order to cover also near solid density plasmas. We present results for the electron-atom contribution to the virial expansion and the corresponding equation of state, i.e. pressure, composition, and chemical potential as a function of density and temperature. These results are compared with semi-empirical approaches to the thermodynamics of partially ionized plasmas. Avoiding any ill-founded input quantities, the Beth-Uhlenbeck second virial coefficient for the electron-atom interaction represents a benchmark for other, semi-empirical approaches.Comment: 16 pages, 10 figures, and 5 tables, resubmitted to PR

БОТУЛИНОТЕРАПИЯ В ЛЕЧЕНИИ ХРОНИЧЕСКОЙ ГОЛОВНОЙ БОЛИ

ABSTRACT. The article deals with the use of botulinum toxin in the treatment of chronic headache. We present four clinical cases of patients who sought treatment in the “Pain Clinic” of N.V. Sklifosovsky Research Institute for Emergency Medicine with a chronic severe cephalgic syndrome of different genesis (migraine, tension headache, dystonia), which had not responded to outpatient treatment for a long time. The paper shows the change of pain in patients with various forms of headache after treatment with botulinum toxin type A, indicating the effectiveness of the method in these patients. РЕЗЮМЕ. Статья посвящена использованию ботулинотерапии в лечении хронической головной боли. Представлены 4 клинических наблюдения пациентов, обратившихся в «Клинику боли» НИИ скорой помощи им. Н.В. Склифосовского с хроническим выраженным цефалгическим синдромом различного генеза (мигрень, головная боль напряжения, дистония), который длительно не поддавался коррекции на амбулаторном этапе лечения. Отражена динамика болевого синдрома у пациентов с различными формами головной боли после лечения ботулиническим токсином типа А, свидетельствующая об эффективности использования метода ботулинотерапии у данной категории больных.

Причины головокружения у больных с подозрением на острое нарушение мозгового кровообращения

Background Acute dizziness may be the only symptom of stroke. Prevalence of this disease among patients with isolated dizziness differs significantly and depends on study design, inclusion criteria and diagnostic methods. In available investigations, we did not find any prospective studies where magnetic resonance imaging, positional maneuvers, and Halmagyi-Curthoys test had been used to clarify a pattern of diseases with isolated acute dizziness and suspected stroke.Aim of study To clarify the pattern of the causes of dizziness in patients with suspected acute stroke.Material and methods We examined 160 patients admitted to N.V. Sklifosovsky Research Institute for Emergency Medicine with suspected stroke and single or underlying complaint of dizziness. All patients were examined with assessment of neurological status, Dix-Hollpike and Pagnini-McClure maneuvers, HalmagyiCurthoys test, triplex scans of brachiocephalic arteries, transthoracic echocardiography, computed tomography (CT) and magnetic resonance imaging (MRI) of the brain with magnetic field strength 1.5 T. MRI of the brain was performed in patients without evidence of stroke by CT and in patients with stroke of undetermined etiology according to the TOAST classification.Results In 16 patients (10%), the cause of dizziness was a disease of the brain: ischemic stroke (n=14 (88%)), hemorrhage (n=1 (6%)), transient ischemic attack (TIA) of posterior circulation (n=1 (6%)). In 70.6% patients (n=113), the dizziness was associated with peripheral vestibulopathy: benign paroxysmal positional vertigo (n=85 (75%)), vestibular neuritis (n=19 (17%)), Meniere’s disease (n=7 (6%)), labyrinthitis (n=2 (1,3%)). In 6.9% patients (n=11), the cause of dizziness was hypertensive encephalopathy, 1.9% of patients (n=3) had heart rhythm disturbance, 9.4% of patients (n=15) had psychogenic dizziness, 0.6% of patients (n=1) had demyelinating disease, and 0.6% of patients (n=1) had hemic hypoxia associated with iron deficiency anemia.Conclusion In 70.6% patients with acute dizziness, admitted to hospital with a suspected stroke, peripheral vestibulopathy was revealed. Only 10% of patients had a stroke as a cause of dizziness.Актуальность Остро возникшее головокружение может быть единственным симптомом острого нарушения мозгового кровообращения (ОНМК). Частота данного заболевания среди пациентов с изолированным головокружением значительно различается и зависит от дизайна исследования, критериев включения и методов диагностики. В доступной литературе мы не обнаружили проспективных исследований, авторы которых применяли бы магнитно-резонансную томографию, позиционные маневры и тест Хальмаги–Кертойза для уточнения структуры заболеваний с изолированным остро возникшим головокружением и подозрением на ОНМК.Цель исследования. Определить структуру причин головокружения у больных с подозрением на ОНМК.Материал и методы. Обследовали 160 больных, поступивших с подозрением на ОНМК и госпитализированных в НИИ СП им. Н.В. Склифосовского с единственной или ведущей жалобой на головокружение. Всем больным определяли неврологический статус, проводили позиционные маневры Дикса– Холлпайка и МакКлюра–Пагнини, тест Хальмаги–Кертойза, выполняли триплексное сканирование брахиоцефальных артерий, трансторакальную эхокардиографию, компьютерную томографию (КТ) и магнитно-резонансную томографию (МРТ) головного мозга с индукцией магнитного поля 1,5 Тл. МРТ головного мозга проводили пациентам, у которых ОНМК не было подтверждено по данным КТ, и пациентам с ишемическим инсультом с неустановленным патогенетическим вариантом по классификации TOAST.Результаты У 16 пациентов (10%) причиной головокружения явились сосудистые заболевания головного мозга: ишемический инсульт (n=14; 88%), геморрагический инсульт (n=1; 6%), транзиторная ишемическая атака в вертебробазилярном бассейне (n=1; 6%). У 70,6% больных (n=113) причиной головокружения была периферическая вестибулопатия: доброкачественное пароксизмальное позиционное головокружение (n=85; 75%), вестибулярный нейронит (n=19; 17%), болезнь Меньера (n=7; 6%), лабиринтит (n=2; 1,3%). У 6,9% пациентов (n=11) причиной головокружения была гипертоническая энцефалопатия, у 1,9% (n=3) — нарушение ритма сердца, у 9,4% (n=15) — психогенное головокружение, у 0,6% (n=1) — демиелинизирующее заболевание, у 0,6 % (n=1) — гемическая гипоксия на фоне железодефицитной анемии.Выводы У 70,6% больных с остро возникшим головокружением, поступающих в стационар с подозрением на ОНМК, выявляют периферические вестибулопатии. Только у 10% пациентов причиной головокружения являются острые нарушения мозгового кровообращения