a new Pc-C boundary section

The widespread, terminal Ediacaran Dengying Formation (~ 551–~ 542 Ma) of South China hosts one of the most prominent negative carbonate carbon isotope excursions in Earth's history and thus bears on the correlation of the Precambrian–Cambrian boundary worldwide. The dominantly carbonate strata of the Dengying Formation are largely studied for their unique preservation of its terminal Ediacaran fauna but their geochemical context is poorly known. This study presents the first high-resolution stable isotope record (δ13C, δ18O) of calcareous siliciclastic shallow-water deposits of the Gaojiashan section (Shaanxi Province). The section includes (in ascending order) the Algal Dolomite Member, the Gaojiashan Member and the Beiwan Member of the Dengying Formation. Our data record a major δ13Ccarb negative excursion to −6 ‰ in the uppermost Gaojiashan Member which is comparable in shape and magnitude to the global Precambrian–Cambrian boundary negative δ13C excursion. Our data set is consistent with a "shallow-water anoxia" scenario which is thought to contribute to the "Cambrian explosion". The stratigraphic occurrence of Cloudina and a large negative δ13C excursion suggest that the Precambrian–Cambrian boundary is located near the top of the Gaojiashan Member and, consequently, that overlying carbonates and dolomites of the Beiwan Member are of earliest Cambrian age. Thus the Gaojiashan section may represent a new shallow-water section spanning the Precambrian–Cambrian boundary. Although bio- and chemostratigraphic data support this novel interpretation, we cannot exclude the possibility that the key excursions may represent a local perturbation indicating a restricted-basin environment

Разработка способов, алгоритмов и программ обнаружения и исправления пакетных или независимых ошибок при передаче данных по каналам связи

Настоящая научно-квалификационная работа посвящена разработке способов, алгоритмов и программ обнаружения и исправления ошибок при передаче данных по каналам связи для обеспечения целостности и надёжности передаваемых команд и данных между устройствами вычислительно техники, а также при считывании данных из запоминающих устройств.The present scientific and qualification work is devoted to the development of methods, algorithms and programs for detecting and correcting errors in the transmission of data over communication channels to ensure the integrity and reliability of the transmitted commands and data between computing devices, as well as when reading data from memory devices

TRAIP is a regulator of the spindle assembly checkpoint.

Accurate chromosome segregation during mitosis is temporally and spatially coordinated by fidelity-monitoring checkpoint systems. Deficiencies in these checkpoint systems can lead to chromosome segregation errors and aneuploidy, and promote tumorigenesis. Here, we report that the TRAF-interacting protein (TRAIP), a ubiquitously expressed nucleolar E3 ubiquitin ligase important for cellular proliferation, is localized close to mitotic chromosomes. Its knockdown in HeLa cells by RNA interference (RNAi) decreased the time of early mitosis progression from nuclear envelope breakdown (NEB) to anaphase onset and increased the percentages of chromosome alignment defects in metaphase and lagging chromosomes in anaphase compared with those of control cells. The decrease in progression time was corrected by the expression of wild-type but not a ubiquitin-ligase-deficient form of TRAIP. TRAIP-depleted cells bypassed taxol-induced mitotic arrest and displayed significantly reduced kinetochore levels of MAD2 (also known as MAD2L1) but not of other spindle checkpoint proteins in the presence of nocodazole. These results imply that TRAIP regulates the spindle assembly checkpoint, MAD2 abundance at kinetochores and the accurate cellular distribution of chromosomes. The TRAIP ubiquitin ligase activity is functionally required for the spindle assembly checkpoint control

Антиоксиданты в яблочном соке

We examined to what degree the visualization of anatomic structures in the human knee is improved using 3.0-T magnetic resonance imaging (MRI) and many element RF receive coils as compared to 1.5 T. We imaged 20 knees at 1.5 and 3.0 T using T2-weighted STIR, T2-weighted gradient echo, T1-weighted spin-echo, true-FISP and T2-weighted fast spin echo techniques in conjunction with 32-element RF coil arrays. The 3.0-T examination was considerably faster than its 1.5-T counterpart. A superior subjective visibility at 3.0 T vs 1.5 T was found in 27 of 50 evaluated structures (meniscus, ligaments) with the exception of true-FISP techniques. The 3.0-T examination provided a better visibility (evaluated by blinded consensus-reading by two radiologists) of small structures such as the ligamentum transversum genu. Also, cartilage was better delineated at 3.0 T. A 23% increased average signal-to-noise ratio as assessed using a temporal filter was observed at 3.0 T as compared to 1.5 T. At 3.0 T, imaging of the human knee is faster and results in a subjective visibility of anatomic structures that is superior to and competitive with 1.5 T

Влияние ширины реза на радиальную проекцию силы резания

В статье обосновывается влияние ширины реза на проекцию составляющей силы резания на плоскость, перпендикулярную оси вращения геохода. Рассмотрена актуальность исследования. Для постановки цели и задач исследования определена проекция составляющей силы резания на плоскость, перпендикулярную оси вращения геохода. На основании проведенного исследования построена зависимость радиальной проекции силы резанию ножевого исполнительного органа геохода (RИО.СВ) от от x до Rг

Quasi-equilibria in one-dimensional self-gravitating many body systems

The microscopic dynamics of one-dimensional self-gravitating many-body systems is studied. We examine two courses of the evolution which has the isothermal and stationary water-bag distribution as initial conditions. We investigate the evolution of the systems toward thermal equilibrium. It is found that when the number of degrees of freedom of the system is increased, the water-bag distribution becomes a quasi-equilibrium, and also the stochasticity of the system reduces. This results suggest that the phase space of the system is effectively not ergodic and the system with large degreees of freedom approaches to the near-integrable one.Comment: 21pages + 7 figures (available upon request), revtex, submitted to Physical Review

Ten‐Year Secular Trends in Youth Violence: Results From the Philadelphia Youth Risk Behavior Survey 2003‐2013

BACKGROUNDYouth violence reduction is a public health priority, yet few studies have examined secular trends in violence among urban youth, who may be particularly vulnerable to numerous forms of violence. This study examines 10‐year secular trends in the prevalence of violence‐related behaviors among Philadelphia high school students.METHODSRepeated cross‐sectional data were analyzed from 5 waves of the Philadelphia Youth Risk Behavior Survey (YRBS) from 2003 to 2013. Sex‐specific multivariate regression models were used to examine secular trends in multiple types of violence, accounting for age, race/ethnicity, and sampling strategy.RESULTSIn 2013, the most prevalent violent behavior was physical fighting among boys (38.4%) and girls (32.7%). Among girls, the prevalence of sexual assault and suicide attempts declined between 2003 and 2013 (β = −0.13, p = .04 and β = −0.14, p = .007, respectively). Among boys, significant declines in carrying a weapon (β = −0.31, p < .001), carrying a gun (β = −0.16, p = .01), and physical fighting (β = −0.35, p = .001) were observed.CONCLUSIONSWhereas the prevalence of some forms of violence stabilized or declined among Philadelphia youth during 2003‐2013 time span, involvement in violence‐related behaviors remains common among this population. Continued surveillance and evidence‐based violence reduction strategies are needed to address violence among urban youth.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136403/1/josh12491_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136403/2/josh12491.pd

TRAINING FOR THE BIKE TO RUN TRANSITION IN TRIATHLON

The purpose of this study was to examine the effect of a practice regimen that targets the bike-to-run transition for triathlons; known as brick workouts. The principle of specificity suggests that since this skill is a critical transition in a triathlon, having further impact on the subsequent running section, practicing this skill is vital for success. Moreover, the identification of performance parameters that quantify a successful transition will serve to maximize practice efficiency. Subjects (N=12) performed either brick workouts or single event training, to examine their effects on the bike-run transition. Our results indicate that the brick workouts had a positive effect by eliciting an increased adaptability in knee behavior in response to the transition from cycling to running. Quicker adoption of efficient running mechanics may ensue, leading to less fatigue and greater performance

Polysomes of bovine anterior pituitary gland and their role in hormone and protein biosynthesis

This article does not have an abstract