Influence of voluntary hypoventilation breathing on the functional state and physical working capacity of a person at different intensity regimes of physical load

Objective: to study the effect of voluntary hypoventilation breathing on the functional state and physical working capacity of a person under various physical load on a bicycle ergometer to failure. Materials and methods: in the survey 14 young volunteers took part in the survey performing physical work on the bicycle ergometer to the point of refusal. Surveys were conducted 4 times: 2 times before training in voluntary hypoventilation breathing and 2 times after. Voluntary hypoventilation breathing was taught for 30 days. Breathing trainings aimed at forming a subject's narrowed breathing underlied the training of voluntary hypoventilation breathing. The subjects' condition was examined sequentially during rest, 60 W warm-up, physical load and recovery after the load. The physical load was at 120 W or 160 W. During work ECG was recorded in two leads: I standard and V5 thoracic. Simultaneously, a pneumogram and EMG from the quadriceps muscle of the right thigh was recorded. The time of physical work to failure was measured. Before and after the examination, the breath-holding time by inhalation was measured. Results: voluntary hypoventilation breathing increased the hypoxic stability and physical working capacity of the subjects at 120 W and 160 W loads. The greater the load, the shorter the time of physical work to failure. Refusal to continue physical work occurred immediately after overcoming the threshold of aerobic-anaerobic metabolism. In contrast to the 120 W physical load, the 160 W load is accompanied by a higher excitability of the ECG sinus node, slower intraventricular conduction, a higher level of sympathetic influences on the heart, but a better oxygen supply of the myocardium. Conclusions: the greater intensity of physical activity, the more pronounced adaptive shifts in the body of subjects under the influence of voluntary hypoventilation breathing

Linear theory of nonlocal transport in a magnetized plasma

A system of nonlocal electron-transport equations for small perturbations in a magnetized plasma is derived using the systematic closure procedure of V. Yu. Bychenkov et al., Phys. Rev. Lett. 75, 4405 (1995). Solution to the linearized kinetic equation with a Landau collision operator is obtained in the diffusive approximation. The Fourier components of the longitudinal, oblique, and transversal electron fluxes are found in an explicit form for quasistatic conditions in terms of the generalized forces: the gradients of density and temperature, and the electric field. The full set of nonlocal transport coefficients is given and discussed. Nonlocality of transport enhances electron fluxes across magnetic field above the values given by strongly collisional local theory. Dispersion and damping of magnetohydrodynamic waves in weakly collisional plasmas is discussed. Nonlocal transport theory is applied to the problem of temperature relaxation across the magnetic field in a laser hot spot.Comment: 27 pages, 13 figure

RNF17 blocks promiscuous activity of PIWI proteins in mouse testes

PIWI proteins and their associated piRNAs protect germ cells from the activity of mobile genetic elements. Two classes of piRNAs-primary and secondary-are defined by their mechanisms of biogenesis. Primary piRNAs are processed directly from transcripts of piRNA cluster loci, whereas secondary piRNAs are generated in an adaptive amplification loop, termed the ping-pong cycle. In mammals, piRNA populations are dynamic, shifting as male germ cells develop. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, the piRNA population is transposon-poor and largely restricted to primary piRNAs derived from pachytene piRNA clusters. The transition from the embryonic to the adult piRNA pathway is not well understood. Here we show that RNF17 shapes adult meiotic piRNA content by suppressing the production of secondary piRNAs. In the absence of RNF17, ping-pong occurs inappropriately in meiotic cells. Ping-pong initiates piRNA responses against not only transposons but also protein-coding genes and long noncoding RNAs, including genes essential for germ cell development. Thus, the sterility of Rnf17 mutants may be a manifestation of a small RNA-based autoimmune reaction

To the question of research on hoisting equipment hydraulic drive dynamics by using it means in educational process

The program "Mobile Mining Hoisting Units Dynamics" has been developed. The programme proposed can be applied while teaching discipline "Dynamics of Mining Machines" to students of a master degree course in the direction 151000.68, also to those studying in specialty 130400.65 whose major is "Mining machinery and Equipment", "Electrification and automation of mining operations" in doing coursework and diploma projects on disciplines "Hydropneumatic electric drive" and "Dynamic Strength"Разработана программа «Динамика мобильных проходческих подъемных установок». Предложенная программа применима при изучении дисциплины «Динамика горных машин» для магистрантов, обучающихся по направлению 151000.68 «Технологические машины и оборудование» и студентов специальности 130400.65 специализаций «Горные машины и оборудование», «Электрификация и автоматизация горного производства» для выполнения курсового и дипломного проектирования по дисциплинам «Гидро- пневмо- электропривод» и «Динамика и прочность

Hypoventilation trainings combined with physical exercises and their influences on person's functional state in physical work to failure

Objective: to study the influence of hypoventilation's trainings combined with physical exercises on the person's functional state and its physical working capacity in physical work to failure. Materials and methods: 18 young men were examined, and it were divided into 2 groups: main (12 persons) and control (6 persons). Only subjects of the main group were studied to hypoventilation breathing in combination with physical exercises. Before and after the training all subjects performed load testing on a bicycle ergometer to failure under ECG, pneumogram and EMG monitoring. Results: hypoventilation breathing combined with physical exercises was increased the work's time to failure from 165,1±25,6 to 307,3±52,0 s (

Laser in the axial electric field as a tool to search for P-, T- invariance violation

We consider rotation of polarization plane of the laser light when a gas laser is placed in a longitudinal electric field (10~kV/cm). It is shown that residual anisotropy of the laser cavity 10^{-6} and the sensitivity to the angle of polarization plane rotation about 10^{-11} -10^{-12} rad allows one to measure an electron EDM with the sensitivity about 10^{-30} e cm.Comment: 12 page

ARP/wARP and molecular replacement: the next generation

A systematic test shows how ARP/wARP deals with automated model building for structures that have been solved by molecular replacement. A description of protocols in the flex-wARP control system and studies of two specific cases are also presented

Гидроакустическое устройство профилирования донного грунта с синтезированной апертурой

Introduction. Acoustic profiling is a conventional method for studying the geological structure of the seabed. To this end, a low-frequency acoustic profiler with an operating frequency range of 1…14 kHz can be used. However, under lower operating frequencies, the difficulty of achieving the required resolution arises. The problem of improving the angular resolution of a hydroacoustic device, particularly in the direction of the carrier movement, remains to be a priority task in the search and detection of objects on the seabed, as well as the study of the bottom soil structure. Angular resolution can be improved through several approaches, including an algorithm for synthesizing the antenna aperture based on the law of the phase change of the reflected signal. This approach is relevant in the design of highresolution hydroacoustic tools.Aim. To demonstrate the possibility of constructing a bottom soil profiling device, as well as the possibility of increasing its angular resolution based on an algorithm for synthesizing the antenna aperture of an acoustic profiler.Materials and methods. The study employed the groundwork data obtained for side-scan sonars with a synthetic aperture in terms of constructing an antenna device and the methods of radio-wave excitation developed for radar systems.Results. The possibility of synthesizing the antenna aperture for an acoustic profiler of the bottom soil was studied. An algorithm for synthesizing the antenna aperture was investigated along with phase distortions of the trajectory signal and their influence on the sonar image. The fundamental principles of processing the trajectory signal were considered.Conclusion. An approach to increasing the resolution of an acoustic profiler when performing search and survey tasks is proposed. The proposed design of the acoustic part of a profiling device can be used in the development of search and survey hydroacoustic devices with a high angular resolution.Введение. Акустическое профилирование является традиционным методом исследования геологического строения морского дна. Для этих целей используется низкочастотный акустический профилограф с рабочим диапазоном частот 1…14 кГц. Однако при понижении рабочих частот возникает проблема с достижением необходимой разрешающей способности.  Проблема повышения углового разрешения гидроакустического устройства, или, иначе говоря, повышение разрешающей способности в направлении движения носителя, является одной из приоритетных задач при поиске и обнаружении объектов на морском дне, исследовании структуры донного грунта. Существует несколько способов повышения углового разрешения, одним из которых является алгоритм синтезирования апертуры антенны, базирующийся на использовании закона изменения фазы отраженного сигнала, что является актуальным при проектировании гидроакустических средств высокого разрешения.Цель работы. Показать возможность построения устройства профилирования донного грунта, а также возможность повышения углового разрешения на основе алгоритма синтезирования апертуры антенны акустического профилографа.Материалы и методы. Исследование возможности построения устройства профилирования донного грунта с использованием алгоритма синтезирования апертуры антенны основано на заделе, полученном для гидролокаторов бокового обзора с синтезированной апертурой в части построения антенного устройства, а также на методах возбуждения радиоволн, разработанных для радиолокационных систем.Результаты. Исследована возможность применения синтезирования апертуры антенны для акустического профилографа донного грунта. Рассмотрен алгоритм синтезирования апертуры антенны, а также фазовые искажения траекторного сигнала и их влияние на гидролокационное изображение, а также основы обработки траекторного сигнала.Заключение. В работе предложен вариант повышения разрешающей способности акустического профилографа при выполнении поисково-обследовательских задач. Предлагаемый вариант построения акустической части устройства профилирования может быть использован при разработке поисково-обследовательских гидроакустических устройств с высоким угловым разрешением

An ATP-binding cassette-type cysteine transporter in Campylobacter jejuni inferred from the structure of an extracytoplasmic solute receptor protein

Campylobacter jejuni is a Gram-negative food-borne pathogen associated with gastroenteritis in humans as well as cases of the autoimmune disease Guillain Barre syndrome. C. jejuni is asaccharolytic because it lacks an active glycolytic pathway for the use of sugars as a carbon source. This suggests an increased reliance on amino acids as nutrients and indeed the genome sequence of this organism indicates the presence of a number of amino acid uptake systems. Cj0982, also known as CjaA, is a putative extracytoplasmic solute receptor for one such uptake system as well as a major surface antigen and vaccine candidate. The crystal structure of Cj0982 reveals a two-domain protein with density in the enclosed cavity between the domains that clearly defines the presence of a bound cysteine ligand. Fluorescence titration experiments were used to demonstrate that Cj0982 binds cysteine tightly and specifically with a K-d of similar to 10(-7) M consistent with a role as a receptor for a high- affinity transporter. These data imply that Cj0982 is the binding protein component of an ABC-type cysteine transporter system and that cysteine uptake is important in the physiology of C. jejuni