Resilience to orthostasis and haemorrhage: A pilot study of common genetic and conditioning mechanisms

A major challenge presently is not only to identify the genetic polymorphisms increasing risk to diseases, but to also find out factors and mechanisms, which can counteract a risk genotype by developing a resilient phenotype. The objective of this study was to examine acquired and innate vagal mechanisms that protect against physical challenges and haemorrhages in 19 athletes and 61 non-athletes. These include examining change in heart rate variability (HF-HRV; an indicator of vagus activity) in response to orthostatic challenge, platelet count (PLT), mean platelet volume (MPV), and single-nucleotide polymorphisms in genes that encode several coagulation factors, PAI-1, and MTHFR. Individual differences in PLT and MPV were significant predictors, with opposite effects, of the profiles of the HF-HRV changes in response to orthostasis. Regular physical training of athletes indirectly (through MPV) modifies the genetic predisposing effects of some haemostatic factors (PAI-1 and MTHFR) on vagal tone and reactivity. Individual differences in vagal tone were also associated with relationships between Factor 12 C46T and Factor 11 C22771T genes polymorphisms. This study showed that genetic predispositions for coagulation are modifiable. Its potential significance is promoting advanced protection against haemorrhages in a variety of traumas and injuries, especially in individuals with coagulation deficits

Microstructure and mechanical properties of V-4Ti-4Cr alloy as a function of the chemical heat treatment regimes

The regularities of the formation of a heterophase structure and mechanical properties of V–4Ti–4Cr alloy as a function of thermomechanical and chemical heat treatments are studied. The regimes of thermomechanical treatment which provide the formation of a heterophase structure with a homogeneous volume distribution of oxycarbonitride nanoparticles with a size of about 10 nm and an increase in the volume content and thermal stability of this phase and which provide an increase in the temperature of alloy recrystallization are developed. The formation of the heterophase structure results in a substantial (up to 70%) increase in the short-term high-temperature strength of the alloy at T = 800°C. The increase in the strength is achieved while keeping a rather high level of plasticity

Constraints on the ionizing flux emitted by T Tauri stars

We present the results of an analysis of ultraviolet observations of T Tauri Stars (TTS). By analysing emission measures taken from the literature we derive rates of ionizing photons from the chromospheres of 5 classical TTS in the range ~10^41-10^44 photons/s, although these values are subject to large uncertainties. We propose that the HeII/CIV line ratio can be used as a reddening-independent indicator of the hardness of the ultraviolet spectrum emitted by TTS. By studying this line ratio in a much larger sample of objects we find evidence for an ionizing flux which does not decrease, and may even increase, as TTS evolve. This implies that a significant fraction of the ionizing flux from TTS is not powered by the accretion of disc material onto the central object, and we discuss the significance of this result and its implications for models of disc evolution. The presence of a significant ionizing flux in the later stages of circumstellar disc evolution provides an important new constraint on disc photoevaporation models.Comment: 8 pages, 5 figures. Accepted for publication in MNRA

DNA metabarcoding of benthic algae and associated eukaryotes from Lake Baikal in the face of rapid environmental changes

Here we report new data describing the biodiversity of phytobenthic communities based on DNA-metabarcoding using the 18S rDNA marker and the Illumina MiSeq system. The study was initiated due to the blooming of filamentous algae (mainly of the genus Spirogyra) and cyanobacteria in the coastal zone of Lake Baikal under climate change and anthropogenic impact. The composition and taxonomic diversity of algae and other organisms associated with them on different sites of Lake Baikal (near Bolshoi Ushkaniy Island, in Listvennichny Bay) and in the Kaya (within the city of Irkutsk, located in the same drainage basin as Lake Baikal) were determined using DNAmetabarcoding. About 15 thousand reads of the 18S rRNA marker were obtained by applying NGS (next-generation sequencing). The species of algae dominating in the number of reads, as well as the difficult-to-identify taxa (Stramenopiles, Alveolata, Euglenozoa, Chromista, Rhizaria, Amoebozoa, etc.), which play an important role in the functioning and formation of the structure of algal communities, were revealed. The Shannon index of the communities studied ranges from 1.56 to 2.72. The advantages and weaknesses of using DNA-metabarcoding based on the 18S rRNA gene fragment for studying the structure of algal communities are shown. The advantage of this method is the possibility to more fully determine the diversity of eukaryotes taxa, which are difficult to identify by morphology, without involving a large number of specialists, while the disadvantage of the method is the distortion that may occur during the PCR. Here, ways of solving this problem are proposed. The results of the study show that the analysis of the minor component of the eukaryotic community in samples (organisms with low biomass) consisting of a mixture of multicellular and unicellular organisms requires a read-depths of at least 100,000 sequences per sample. In general, the DNA-metabarcoding method is recommended for studying the structure of algal communities and eukaryotes associated with them

The Energy Level Shifts, Wave Functions and the Probability Current Distributions for the Bound Scalar and Spinor Particles Moving in a Uniform Magnetic Field

We discuss the equations for the bound one-active electron states based on the analytic solutions of the Schrodinger and Pauli equations for a uniform magnetic field and a single attractive $\delta({\bf r})$-potential. It is vary important that ground electron states in the magnetic field differ essentially from the analogous state of spin-0 particles, whose binding energy was intensively studied more than forty years ago. We show that binding energy equations for spin-1/2 particles can be obtained without using the language of boundary conditions in the $\delta$-potential model developed in pioneering works. We use the obtained equations to calculate the energy level displacements analytically and demonstrate nonlinear dependencies on field intensity. We show that the magnetic field indeed plays a stabilizing role in considered systems in a case of the weak intensity, but the opposite occurs in the case of strong intensity. These properties may be important for real quantum mechanical fermionic systems in two and three dimensions. We also analyze the exact solution of the Pauli equation for an electron moving in the potential field determined by the three-dimensional $\delta$-well in the presence of a strong magnetic field. We obtain asymptotic expressions for this solution for different values of the problem parameters. In addition, we consider electron probability currents and their dependence on the magnetic field. We show that including the spin in the framework of the nonrelativistic approach allows correctly taking the effect of the magnetic field on the electric current into account. The obtained dependencies of the current distribution, which is an experimentally observable quantity, can be manifested directly in scattering processes, for example.Comment: 31 pages, 10 figure

Сравнительное исследование фармакокинетики и биораспределения карбазольного соединения CBL0100 в составе различных топических лекарственных форм на морских свинках

An experimental drug CBL0100 is developed as an antifungal agent for topical application. In order to assess the effect of composition of the formulation on transdermal absorption, a comparative absorption study of its pharmacokinetics and biodistribution after a single topical application on the guinea pigs' skin. Two different formulations of CBL0100 (prototypes of final dosage forms for topical applications) - cream emulsion and polyethylene glycol vehicles with a content of active substance 1, 0,2 and 0,02% mass. in each of these formulations were used in the study. CBL0100 concentration in blood plasma and homogenates of organs and tissues of animals was analyzed by HPLC - MS/MS. During the preliminary blood-to-plasma partitioning in vitro experiment it was determined that CBL0100 is found mostly in the cell fraction of the blood, which, based upon the pharmacokinetic curves shape affects elimination from plasma. It was revealed that after a single topical application active compound enters the systemic circulation and intensively distributed into the spleen, liver, kidneys and lungs of guinea pigs. At the same time, its content in the muscular tissue and the heart is negligible; CBL0100 moderately penetrates into the brain. In general, it was shown that the emulsion composition provides improved bioavailability of CBL0100 compared to the polyethylene glycol composition.Экспериментальный препарат CBL0100 разрабатывается в качестве противогрибкового средства для местного применения. Для оценки влияния состава лекарственной формы на трансдермальное всасывание было проведено сравнительное исследование его фармакокинетики и биораспределения после однократного нанесения на кожу морских свинок. В исследовании использовали две различные прописи CBL0100 (прототипы готовых лекарственных форм для топических аппликаций) - крема на эмульсионной (ЭМ) и полиэтиленгликолевой (ПЭГ) основах с содержанием активного вещества 1, 0,2 и 0,02% по массe. Концентрацию активного вещества в плазме крови и гомогенатах органов и тканей животных определяли методом ВЭЖХ-МС/ МС. В предварительном эксперименте по изучению распределения CBL0100 между плазмой и клеточными компонентами крови in vitro установлено, что исследуемое соединение преимущественно обнаруживается в клеточной фракции крови, что, судя по форме фармакокинетических кривых, влияет на скорость его элиминации из плазмы. Показано, что после однократного накожного нанесения крема CBL0100 проникает в системный кровоток и интенсивно распределяется в селезёнку, печень, почки и лёгкие морских свинок. В то же время его содержание в мышечной ткани и сердце незначительно; в мозг CBL0100 проникает умеренно. Установлено, что пропись на ЭМ основе обеспечивает повышенную по сравнению ПЭГ основой биодоступность CBL0100

Life events as antecedents and triggers of manifestation and recurrence of mental and somatic disorders

The purpose of the study is to assess the difference between the type of stressful life events, distressing feelings and coping strategies that precede mental and somatic disorders.Цель исследования – оценить разницу между типом стрессогенных жизненных событий, дистрессирующих чувств и копинг-стратегий, предшествующих рецидивами или манифестациям психических и соматических расстройств