Realistic Magnetohydrodynamical Simulation of Solar Local Supergranulation

Three-dimensional numerical simulations of solar surface magnetoconvection using realistic model physics are conducted. The thermal structure of convective motions into the upper radiative layers of the photosphere, the main scales of convective cells and the penetration depths of convection are investigated. We take part of the solar photosphere with size of 60x60 Mm in horizontal direction and by depth 20 Mm from level of the visible solar surface. We use a realistic initial model of the Sun and apply equation of state and opacities of stellar matter. The equations of fully compressible radiation magnetohydrodynamics with dynamical viscosity and gravity are solved. We apply: 1) conservative TVD difference scheme for the magnetohydrodynamics, 2) the diffusion approximation for the radiative transfer, 3) dynamical viscosity from subgrid scale modeling. In simulation we take uniform two-dimesional grid in gorizontal plane and nonuniform grid in vertical direction with number of cells 600x600x204. We use 512 processors with distributed memory multiprocessors on supercomputer MVS-100k in the Joint Computational Centre of the Russian Academy of Sciences.Comment: 6 pages, 5 figures, submitted to the proceedings of the GONG 2008 / SOHO XXI conferenc

Simulating Supersonic Turbulence in Magnetized Molecular Clouds

We present results of large-scale three-dimensional simulations of weakly magnetized supersonic turbulence at grid resolutions up to 1024^3 cells. Our numerical experiments are carried out with the Piecewise Parabolic Method on a Local Stencil and assume an isothermal equation of state. The turbulence is driven by a large-scale isotropic solenoidal force in a periodic computational domain and fully develops in a few flow crossing times. We then evolve the flow for a number of flow crossing times and analyze various statistical properties of the saturated turbulent state. We show that the energy transfer rate in the inertial range of scales is surprisingly close to a constant, indicating that Kolmogorov's phenomenology for incompressible turbulence can be extended to magnetized supersonic flows. We also discuss numerical dissipation effects and convergence of different turbulence diagnostics as grid resolution refines from 256^3 to 1024^3 cells.Comment: 10 pages, 3 figures, to appear in the proceedings of the DOE/SciDAC 2009 conferenc

Validated helioseismic inversions for 3-D vector flows

According to time-distance helioseismology, information about internal fluid motions is encoded in the travel times of solar waves. The inverse problem consists of inferring 3-D vector flows from a set of travel-time measurements. Here we investigate the potential of time-distance helioseismology to infer 3-D convective velocities in the near-surface layers of the Sun. We developed a new Subtractive Optimally Localised Averaging (SOLA) code suitable for pipeline pseudo-automatic processing. Compared to its predecessor, the code was improved by accounting for additional constraints in order to get the right answer within a given noise level. The main aim of this study is to validate results obtained by our inversion code. We simulate travel-time maps using a snapshot from a numerical simulation of solar convective flows, realistic Born travel-time sensitivity kernels, and a realistic model of travel-time noise. These synthetic travel times are inverted for flows and the results compared with the known input flow field. Additional constraints are implemented in the inversion: cross-talk minimization between flow components and spatial localization of inversion coefficients. Using modes f, p1 through p4, we show that horizontal convective flow velocities can be inferred without bias, at a signal-to-noise ratio greater than one in the top 3.5 Mm, provided that observations span at least four days. The vertical component of velocity (v_z), if it were to be weak, is more difficult to infer and is seriously affected by cross-talk from horizontal velocity components. We emphasise that this cross-talk must be explicitly minimised in order to retrieve v_z in the top 1 Mm. We also show that statistical averaging over many different areas of the Sun allows for reliably measuring of average properties of all three flow components in the top 5.5 Mm of the convection zone.Comment: 14 pages main paper, 9 pages electronic supplement, 28 figures. Accepted for publication in Astronomy & Astrophysic

Организация реабилитации больных острым коронарным синдромом в Красноярском крае

Aim. To evaluate the program of rehabilitation services for patients with ACS over the last six years in the Krasnoyarsk Region.Methods. Data from the National report on the key performance indicators of the Regional Vascular Centers and Primary Vascular Departments of the Krasnoyarsk Region from 2012 to 2017; National reports on the population health of the Krasnoyarsk Region from 2012 to 2017; reports of the healthcare institutions providing outpatient rehabilitation for patients with ACS in the Krasnoyarsk Region were included in the analysis.Results. Over the past six years the number of patients with ACS decreased in the Krasnoyarsk Region. There were 15,923 patients suffered from ACS in 2012, in 2013 - 13,119, in 2014 - 11,192, in 2015 - 11,019, in 2016 - 10,985, and in 2017 - 9,903. The number of patients with ACS decreased due to the exclusion of patients with unstable angina (UA), while the number of patients with acute myocardial infarction (AMI) remained constant and varied from 5,000 to 5,500 patients. The majority of ACS patients were treated in the Regional Vascular Centers and Primary Vascular Departments where they successfully underwent Phase 1 of the rehabilitation program. At di, all patients were referred to Phase 2 of the rehabilitation program (in-patient) performed in the sanatorium “Yenissei” and “Krasnoyarsk Zagoije”. Phase 3 of the rehabilitation program was provided in the Center of modern cardiology and Professorial Clinic of Krasnoyarsk State Medical University named after Professor V.F. Voino-Yasenetsky. The number of ACS patients who underwent rehabilitation after hospital discharge increased over the last years: 5.9% - in 2012, 8.8% - in 2013, 11.9% - in 2014, 13.1% - in 2015, 14.4% - in 2016, 17.1% in 2017.Conclusion. The majority of patients with acute coronary syndrome (76.4-81.2%) underwent Phase 1 (early in-patient) rehabilitation in the Regional Vascular Centers and Primary Vascular Departments. The number of ACS patients who underwent Phase 2 rehabilitation had been increasing annually. Over the past 6 years the percentage of patients had increased from 5.9% to 17.1%. However, only one-sixth of patients with ACS underwent Phase 3 rehabilitation after hospital discharge. Therefore, the improvements in the management of Phase 2 (in-patient) and Phase 3 the (outpatient) through the integration with the regional hospitals of the Krasnoyarsk Region, increase in the numbers of government contracts in Krasnoyarsk, and formation of the reliable continuity between Phase 2 and Phase rehabilitation are required.Цель. Проанализировать проведение реабилитационных мероприятий у пациентов с острым коронарным синдромом (ОКС) за последние шесть лет в Красноярском крае.Материалы и методы. Нами были проанализированы: «Отчеты об основных показателях регионального сосудистого центра (РСЦ) и первичных сосудистых отделений (ПСО).. .Красноярского края за 2012-2017 гг.»; «Государственные доклады о состоянии здоровья населения Красноярского края в 2012-2017 гг.»; отчеты лечебных учреждений, занимающихся реабилитацией пациентов ОКС на амбулаторном этапе в Красноярском крае.Результаты. В течение последних шести лет количество пациентов ОКС в Красноярском крае снижалось. В 2012 г. их было 15923 человека, в 2013 г. - 13119, в 2014 г. - 11192, 2015 г. - 11019, 2016 г. - 10985, 2017 г. - 9903. Количество больных с ОКС снизилось за счет пациентов с нестабильной стенокардией, количество больных с острым инфарктом миокарда все эти годы было постоянным и колебалось от 5 до 5,5 тысячи человек. Большинство пациентов с ОКС получали лечение в РСЦ или ПСО, где в полном объеме прошли первый этап реабилитации. После выписки из стационара пациенты проходили второй этап реабилитации в санаториях «Енисей» и «Красноярское Загорье», третий этап - в «Центре современной кардиологии» и Профессорской клинике медицинского университета. Количество пациентов с ОКС, прошедших реабилитацию после выписки из стационара, за эти годы увеличивалось: в 2012 г. 5,9%, в 2013 г. -8,8%, в 2014 г. - 11,9%, в 2015 г. - 13,1%, в 2016 г. - 14,4%, в 2017 г. - 17,1%.Заключение.Большинство пациентов с ОКС (76,4-81,2%) проходят в полном объеме первый (ранний стационарный) этап реабилитации в РСЦ/ПСО. Наблюдается ежегодный рост числа пациентов с ОКС, прошедших после выписки из стационара кардиореабилитацию. За 6 лет этот показатель увеличился с 5,9% до 17,1%. В то же время только одна шестая часть больных ОКС проходят реабилитационные мероприятия после выписки из клиники. Необходимо совершенствовать работу второго (стационарного) и третьего (амбулаторного) этапов реабилитации за счет вовлечения в процесс реабилитации лечебных учреждений в регионах края, увеличения объемов госзаказа в краевом центре и улучшения преемственности между вторым и третьим этапами реабилитации

Alterations in the nigrostriatal system following conditional inactivation of α-synuclein in neurons of adult and aging mice

The aetiology and pathogenesis of Parkinson’s disease (PD) are tightly linked to he gain-offunction of α-synuclein. However, gradual accumulation of α-synuclein aggregates in dopaminergic neurons of substantia nigra pars compacta (SNpc) leads to the depletion of the functional pool of soluble α-synuclein and therefore, creates a loss-of-function conditions, particularly in presynaptic terminals of these neurons. Studies of if and how this late-onset depletion of a protein involved in many important steps of neurotransmission contributes to PD progression and particularly, to worsening the nigrostriatal pathology at late stages of the disease are limited and obtained data are controversial. Recently we produced a mouse line for conditional knockout of the gene encoding α-synuclein and here we used its tamoxifen-inducible pan-neuronal inactivation to study consequences of the adult-onset (from the age of 6 months) and late-onset (from the age of 12 months) α-synuclein depletion to the nigrostriatal system. No significant changes of animal balance/coordination, the number of dopaminergic neurons in the SNpc and the content of dopamine and its metabolites in the striatum were observed after adult-onset α synuclein depletion but in ageing (18-month old) late-onset depleted mice we found significant reduction of major dopamine metabolites without changes to the content of dopamine itself. Our data suggest that this might be caused, at least partially, by reduced expression of aldehyde dehydrogenase ALDH1a1 and could lead to accumulation of toxic intermediates of dopamine catabolism. By extrapolating our findings to a potential clinical situation, we suggest that therapeutic downregulation of α-synuclein expression in PD patients is a generally safe option as it should not cause adverse side effects on the functionality of their nigrostriatal system. However, if started in aged patients, this type of therapy might trigger slight functional changes of the nigrostriatal system with potentially unwanted additive effect to already existing pathology

The Quiet-Sun Photosphere and Chromosphere

The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top, and small-scale vorticity. Classical 1D static radiation-escape modelling has been replaced by 3D time-dependent MHD simulations that come closer to reality. The solar chromosphere, in contrast, remains ill-understood although its pivotal role in coronal mass and energy loading makes it a principal research area. Its fine structure defines its overall structure, so that hard-to-observe and hard-to-model small-scale dynamical processes are the key to understanding. However, both chromospheric observation and chromospheric simulation presently mature towards the required sophistication. The open-field features seem of greater interest than the easier-to-see closed-field features.Comment: Accepted for special issue "Astrophysical Processes on the Sun" of Phil. Trans. Royal Soc. A, ed. C. Parnell. Note: clicking on the year in a citation opens the corresponding ADS abstract page in the browse

Dimebon Does Not Ameliorate Pathological Changes Caused by Expression of Truncated (1–120) Human Alpha-Synuclein in Dopaminergic Neurons of Transgenic Mice

Background: Recent clinical studies have demonstrated that dimebon, a drug originally designed and used as a non-selective antihistamine, ameliorates symptoms and delays progress of mild to moderate forms of Alzheimer’s and Huntington’s diseases. Although the mechanism of dimebon action on pathological processes in degenerating brain is elusive, results of studies carried out in cell cultures and animal models suggested that this drug might affect the process of pathological accumulation and aggregation of various proteins involved in the pathogenesis of proteinopathies. However, the effect of this drug on the pathology caused by overexpression and aggregation of alpha-synuclein, including Parkinson’s disease (PD), has not been assessed. Objective: To test if dimebon affected alpha-synuclein-induced pathology using a transgenic animal model. Methods: We studied the effects of chronic dimebon treatment on transgenic mice expressing the C-terminally truncated (1–120) form of human alpha-synuclein in dopaminergic neurons, a mouse model that recapitulates several biochemical, histopathological and behavioral characteristics of the early stage of PD. Results: Dimebon did not improve balance and coordination of aging transgenic animals or increase the level of striatal dopamine, nor did it prevent accumulation of alpha-synuclein in cell bodies of dopaminergic neurons. Conclusion: Our observations suggest that in the studied model of alpha-synucleinopathy dimebon has very limited effect on certain pathological alterations typical of PD and related diseases

Low level of expression of C-terminally truncated human FUS causes extensive changes in the spinal cord transcriptome of asymptomatic transgenic mice

A number of mutations in a gene encoding RNA-binding protein FUS have been linked to the development of a familial form of amyotrophic lateral sclerosis known as FUS-ALS. C-terminal truncations of FUS by either nonsense or frameshift mutations lead to the development of FUS-ALS with a particularly early onset and fast progression. However, even in patients bearing these highly pathogenic mutations the function of motor neurons is not noticeably compromised for at least a couple of decades, suggesting that until cytoplasmic levels of FUS lacking its C-terminal nuclear localisation signal reaches a critical threshold, motor neurons are able to tolerate its permanent production.In order to identify how the nervous system responds to low levels of pathogenic variants of FUS we produced and characterised a mouse line, L-FUS[1-359], with a low neuronal expression level of a highly aggregation-prone and pathogenic form of C-terminally truncated FUS. In contrast to mice that express substantially higher level of the same FUS variant and develop severe early onset motor neuron pathology, L-FUS[1-359] mice do not develop any clinical or histopathological signs of motor neuron deficiency even at old age. Nevertheless, we detected substantial changes in the spinal cord transcriptome of these mice compared to their wild type littermates. We suggest that at least some of these changes reflect activation of cellular mechanisms compensating for the potentially damaging effect of pathogenic FUS production. Further studies of these mechanism might reveal effective targets for therapy of FUS-ALS and possibly, other forms of ALS

C9ORF72 hexanucleotide repeat expansion in ALS patients from the Central European Russia population

Cohorts of amyotrophic lateral sclerosis (ALS) patients and control individuals of Caucasian origin from the Central European Russia (Moscow city and region) were analyzed for the presence of hexanucleotide repeat GGGGCC expansion within the first intron of the C9ORF72 gene. The presence of a large (>40) repeat expansion was found in 15% of familial ALS cases (3 of 20 unrelated familial cases) and 2.5% of sporadic ALS cases (6 of 238) but in none of control cases. These results suggest that the frequency of C9ORF72 hexanucleotide repeats expansions in the Central Europea