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

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

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 /

A Hierarchical Taxonomy of Psychopathology Can Transform Mental Health Research

For more than a century, research on psychopathology has focused on categorical diagnoses. Although this work has produced major discoveries, growing evidence points to the superiority of a dimensional approach to the science of mental illness. Here we outline one such dimensional system—the Hierarchical Taxonomy of Psychopathology (HiTOP)—that is based on empirical patterns of co-occurrence among psychological symptoms. We highlight key ways in which this framework can advance mental-health research, and we provide some heuristics for using HiTOP to test theories of psychopathology. We then review emerging evidence that supports the value of a hierarchical, dimensional model of mental illness across diverse research areas in psychological science. These new data suggest that the HiTOP system has the potential to accelerate and improve research on mental-health problems as well as efforts to more effectively assess, prevent, and treat mental illness.FSW – Publicaties zonder aanstelling Universiteit Leide