Experimental study of laboratory-heated CM2 chondrites Mighei and Murchison

We conducted experimental heating of two CM2 chondrites, Murchison and Mighei, to study changes in their oxygen isotopic compositions and mineralogy and explore possible genetic relationships between MCCs and normal CMs

Isheyevo Meteorite: Genetic link between CH and CB chondrites?

Based on the mineralogy, petrography, bulk chemical, oxygen, and nintrogen isotopic compositions and 40Ar-39Ar age, Isheyevo is genetically related to CH and CB carbonaceous chondrites and provides a link between these group of pristine meteorites

The Effect of Adding Calcium Stearate on Wear-resistance of Ultra-high Molecular Weight Polyethylene

AbstractIn order to find an effective solid lubrication filler for the composites based on ultra-high molecular weight polyethylene, tribotechnical properties of UHMWPE and its blends with calcium stearate (С36Н70СаО4, CS) under dry friction, boundary lubrication and abrasion were studied. It is demonstrated that wear rate of UHMWPE-CS compositions under dry sliding friction decreases by more than 4 times as compared to pure UHMWPE while the mechanicals properties do not change substantially. Under abrasion conditions the wear rate of the stated composites rises with the increased content of the filler. The optimal filler weight fraction is determined in terms of ensuring maximum wear resistance. The wear mechanisms of UHMWPE-based polymer compounds with a solid lubrication filler under dry sliding friction conditions and abrasion are discussed

Ресурсоэффективные системы в управлении и контроле: взгляд в будущее: сборник научных трудов VII Международной конференции школьников, студентов, аспирантов, молодых ученых, 8 -13 октября 2018 г., г. Томск

В сборнике представлены материалы VII Международной конференции школьников, студентов, аспирантов, молодых ученых "Ресурсоэффективные системы в управлении и контроле: взгляд в будущее". Более 500 авторов из 35 вузов, предприятий и научных исследовательских университетов России, ближнего и дальнего зарубежья представили тезисы своих докладов, в которых рассматриваются актуальные проблемы неразрушающего контроля и технической диагностики, внедрения систем менеджмента, качества образования, управления в современной экономике. Материалы предназначены для специалистов, преподавателей, аспирантов и студентов вузов, а также для всех интересующихся проблемами ресурсоэффективных технологий

Reducible connections and non-local symmetries of the self-dual Yang-Mills equations

We construct the most general reducible connection that satisfies the self-dual Yang-Mills equations on a simply connected, open subset of flat $\mathbb{R}^4$. We show how all such connections lie in the orbit of the flat connection on $\mathbb{R}^4$ under the action of non-local symmetries of the self-dual Yang-Mills equations. Such connections fit naturally inside a larger class of solutions to the self-dual Yang-Mills equations that are analogous to harmonic maps of finite type.Comment: AMSLatex, 15 pages, no figures. Corrected in line with the referee's comments. In particular, restriction to simply-connected open sets now explicitly stated. Version to appear in Communications in Mathematical Physic

Ассоциация полиморфных вариантов гена мозгового нейротрофического фактора (BDNF rs6265) и гена переносчика глутамата второго типа (SLC1A2 rs4354668) с течением рассеянного склероза у пациентов, проживающих в Томской области

Background: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that affects people of working age and ultimately leads to disability. This disease is of polygenic origin. The role of factors related to the pathogenesis of the disease and affecting both neuroinflammation and remyelination is studied. Aims: Our goal was to investigate the association of single nucleotide polymorphisms BDNF rs6265 and SLC1A2 rs4354668 with the risk of occurrence, clinical manifestations and the course of MS.Materials and methods: The study included 302 patients with MS, 268 healthy volunteers were enrolled in a control group. The obtained blood was used for DNA extraction by standard phenol-chloroform method. The identification of allelic variants of genes SLC1A2 (rs4354668) and BDNF (rs6265) was performed by polymerase chain reaction.Results: When comparing the frequencies of genotypes and alleles of polymorphic variants of BDNF and SLC1A2 genes between the groups of MS patients and the control group, no statistically significant differences were revealed. Comparison of genotype and allele frequencies of patients depending on sex, age of onset of the disease also did not reveal statistically significant differences. The study of the association of polymorphic variant of the gene BDNF (rs6265) with clinical manifestations of the disease revealed the association of genotype CC with oculomotor and trigeminal disorders at the onset of the disease (F=7, p=0.017). The study of the polymorphic variant rs4354668 of the glutamate transporter gene SLC1A2 revealed the association of allele G with an earlier (within 5 years from the moment of debut) transition of the disease to the stage of secondary progression, despite the therapy with DMT (χ2=5.940; p=0.010; OR 1.58; 95% CI 1.09−2.29). Homozygous genotype of TT (χ2=6.393; p=0.041; OR 0.50; 95% CI 0.28−0.88) and allele T (χ2=5.940; p=0.010; OR 0.63; 95% CI 0.44−0.92) of the polymorphism rs4354668 of the glutamate transporter gene SLC1A2 are significantly more common in the group of patients with late transition (15 years or more from the moment of debut) to the secondary progressive course.Conclusions: In our study we revealed the relationship of the studied polymorphic variants of genes with clinical signs at the onset of the disease and with the clinical manifestations of MS in patients living in the Tomsk region.Обоснование. Рассеянный склероз ― аутоиммунное заболевание нервной системы, поражающее людей трудоспособного возраста и приводящее в конечном итоге к инвалидизации. В последние годы наблюдается рост числа больных, связанный как с истинным увеличением заболеваемости, так и с качеством диагностики.Цель исследования ― оценка ассоциации однонуклеотидных полиморфных вариантов генов BDNF rs6265 и SLC1A2 rs4354668 с риском возникновения, клиническими проявлениями и течением рассеянного склероза.Методы. В исследование было включено 302 пациента с рассеянным склерозом, 268 здоровых добровольцев составили группу контроля. Пациенты находились на лечении в неврологической клинике Сибирского государственного медицинского университета. Определение аллельных вариантов генов SLC1A2 (rs4354668) и BDNF (rs6265) проводили методом полимеразной цепной реакции. Амплификацию и анализ результатов осуществляли с помощью приборов StepOnePlus и Quant Studio 5 (Applied Biosystems, США).Результаты. При сравнении частоты генотипов и аллелей полиморфных вариантов генов BDNF и SLC1A2 между группами пациентов с рассеянным склерозом и группой контроля статистически значимых различий не выявлено. Сравнение частоты генотипов и аллелей пациентов в зависимости от пола, возраста начала заболевания также статистически значимых различий не выявило. При исследовании связи полиморфного варианта гена BDNF (rs6265) с клиническими проявлениями болезни найдена ассоциация генотипа СС с глазодвигательными и тригеминальными расстройствами в дебюте заболевания (F=7; p=0,017). При исследовании полиморфного варианта rs4354668 гена глутаматного транспортера SLC1A2 выявлена ассоциация аллеля G с более ранним (в течение 5 лет от момента дебюта) переходом заболевания в стадию вторичного прогрессирования, несмотря на терапию препаратами, изменяющими течение рассеянного склероза (χ2=5,940; р=0,010; OR 1,58; 95% CI 1,09−2,29). Гомозиготный генотип ТТ (χ2=6,393; р=0,041; OR 0,50; 95% CI 0,28−0,88) и аллель Т (χ2=5,940; р=0,010; OR 0,63; 95% CI 0,44−0,92) полиморфизма rs4354668 гена глутаматного транспортера SLC1A2 статистически значимо чаще встречаются в группе пациентов с поздним переходом (через 15 и более лет от момента дебюта) во вторично-прогрессирующее течение.Заключение. В нашем исследовании выявлена связь изучаемых полиморфных вариантов генов с клиническими признаками в дебюте заболевания и с особенностью течения заболевания у пациентов, проживающих на территории Томской области

Nitrogen functional chemistry of organic grains in CR Chondrites and IDPs

80th Annual Meeting of the Meteoritical Society (2017

Impact analysis of accidents on the traffic flow based on massive floating car data

The wide usage of GPS-equipped devices enables the mass recording of vehicle movement trajectories describing the movement behavior of the traffic participants. An important aspect of the road traffic is the impact of anomalies, like accidents, on traffic flow. Accidents are especially important as they contribute to the the aspects of safety and also influence travel time estimations. In this paper, the impact of accidents is determined based on a massive GPS trajectory and accident dataset. Due to the missing precise date of the accidents in the data set used, first, the date of the accident is estimated based on the speed profile at the accident time. Further, the temporal impact of the accident is estimated using the speed profile of the whole day. The approach is applied in an experiment on a one month subset of the datasets. The results show that more than 72% of the accident dates are identified and the impact on the temporal dimension is approximated. Moreover, it can be seen that accidents during the rush hours and on high frequency road types (e.g. motorways, trunks or primaries) have an increasing effect on the impact duration on the traffic flow

Investigation of Some Physical Properties of Accretion Induced Collapse in Producing Millisecond Pulsars

We investigate some physical characteristics of Millisecond Pulsar (MSP) such as magnetic fields, spin periods and masses, that are produced by Accretion Induced Collapse (AIC) of an accreting white dwarf (WD) in stellar binary systems. We also investigate the changes of these characteristics during the mass-transfer phase of the system in its way to become a MSP. Our approach allows us to follow the changes in magnetic fields and spin periods during the conversion of WDs to MSPs via AIC process. We focus our attention mainly on the massive binary WDs (M > 1.0Msun) forming cataclysmic variables, that could potentially evolve to reach Chandrasekhar limit, thereafter they collapse and become MSPs. Knowledge about these parameters might be useful for further modeling of the observed features of AIC.Comment: 9 Pages, 4 figure

Early carboniferous brachiopod faunas from the Baoshan block, west Yunnan, southwest China

38 brachiopod species in 27 genera and subgenera are described from the Yudong Formation in the Shidian-Baoshan area, west Yunnan, southwest China. New taxa include two new subgenera: Unispirifer (Septimispirifer) and Brachythyrina (Longathyrina), and seven new species: Eomarginifera yunnanensis, Marginatia cylindrica, Unispirifer (Unispirifer) xiangshanensis, Unispirifer (Septimispirifer) wafangjieensis, Brachythyrina (Brachythyrina) transversa, Brachythyrina (Longathyrina) baoshanensis, and Girtyella wafangjieensis. Based on the described material and constraints from associated coral and conodont faunas, the age of the brachiopod fauna from the Yudon Formation is considered late Tournaisian (Early Carboniferous), with a possibility extending into earlyViseacutean.<br /