892 research outputs found

    The peculiar velocity field: constraining the tilt of the Universe

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    A large bulk flow, which is in tension with the Lambda Cold Dark Matter (Λ\LambdaCDM) cosmological model, has been observed. In this paper, we provide a physically plausible explanation of this bulk flow, based on the assumption that some fraction of the observed dipole in the cosmic microwave background is due to an intrinsic fluctuation, so that the subtraction of the observed dipole leads to a mismatch between the cosmic microwave background (CMB) defined rest frame and the matter rest frame. We investigate a model that takes into account the relative velocity (hereafter the tilted velocity) between the two frames, and develop a Bayesian statistic to explore the likelihood of this tilted velocity. By studying various independent peculiar velocity catalogs, we find that: (1) the magnitude of the tilted velocity uu is around 400 km/s, and its direction is close to what is found from previous bulk flow analyses; for most catalogs analysed, u=0 is excluded at about the 2.5σ2.5 \sigma level;(2) constraints on the magnitude of the tilted velocity can result in constraints on the duration of inflation, due to the fact that inflation can neither be too long (no dipole effect) nor too short (very large dipole effect); (3) Under the assumption of a super-horizon isocurvature fluctuation, the constraints on the tilted velocity require that inflation lasts at least 6 e-folds longer (at the 95% confidence interval) than that required to solve the horizon problem. This opens a new window for testing inflation and models of the early Universe from observations of large scale structure.Comment: 7 pages, 7 figures, match the published version in Phys.Rev.

    THE PREVALENCE AND CAUSE OF NON-CONTACT INJURY MECHANISMS IN U.S. MEN’S RUGBY-7S

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    The aim of this study was to prospectively report non-contact injury incidence and causes in U.S. men’s Rugby-7s players (n=446) over 2010-2015, using the Rugby Injury Survey & Evaluation (RISE) methodology. Non-contact injuries (time-loss 25%; medical attention 75%) had higher rates among backs (62%; 28.4/1000ph) than forwards (38%; 23.2/1000ph; RR:1.22; p=0.05). Non-contact injuries resulted in an average of 48.7days (d) absence from sport (classic non-contact 48.1d; other non-contact 77.0d). Acute injuries (85%) were most common during attempts to elude a tackle (31%) and in running/open play (48% overall; from 35% in 2010, 41% in 2011, 52% in 2012, 43% in 2013, 46% in 2014, 70% in 2015). Most non-contact injuries (44%) occurred during the first two tournament matches. These results provide much needed data on Rugby-7s, impacting emerging countries

    THE INCIDENCE AND NATURE OF NON-CONTACT INJURIES IN U.S. WOMEN’S RUGBY-7S

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    The aim of this study was to prospectively determine non-contact injury incidence and mechanisms among U.S. amateur women’s Rugby-7s. Non-contact injuries occurred frequently among the U.S. women population (26.5/1000ph; 29% of all injuries; n=167). The incidence of non-contact injuries occurred at similar rates among backs (58%, 23.9/1000ph, CI:19.1-29.6) and forwards (42%, 19.3/1000ph, CI:14.4-25.3; RR:1.04, p=0.816). Non-contact injuries resulted in 58.4 mean days absence from play. This study demonstrates a greater proportion of match injuries among U.S. amateur women Rugby-7 participants were related to non-contact mechanism when compared to International women participants. Therefore, U.S. women Rugby-7 players would benefit from prevention programs to minimize non-contact injury risks

    USA WOMENS RUGBY SEVENS CONTACT INJURY RISK FACTORS

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    The purpose of the study was to identify the rates and causes of contact injuries in U.S. women’s Rugby-7s tournament players (2010-2015) and present guidelines for injury prevention to reduce the risk of injury in this emerging female contact-sport athlete. Data were captured using the Rugby Injury Survey & Evaluation (RISE) methodology. Contact injuries were frequent over the study period (direct=56%; indirect=38%, unknown=6%). Contact injuries overall were similar among positions (

    BIOMECHANICAL CONTACT INJURY INFLUENCES IN USA MENS RUGBY-7S

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    The aim of this study was to prospectively report injury incidence and contact mechanisms in U.S. men’s under-19 to elite Rugby-7s players (n=852) over 2010-2015, using the Rugby Injury Survey & Evaluation (RISE) methodology. Contact injuries occurred with frequency (Overall, including time-loss and medical attention=55.4/1000ph; time-loss=17.2/1000ph;

    The many alternative faces of macrophage activation

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    Monocytes and macrophages provide the first line of defense against pathogens. They also initiate acquired immunity by processing and presenting antigens and provide the downstream effector functions. In large gene expression datasets from multiple cells and tissues, it is possible to identify sets of genes that are co-regulated with the transcription factors that regulate them. In macrophages, they include lineage-specific genes, interferon-responsive genes, early inflammatory genes, and those associated with endocytosis. Macrophages enter tissues and alter their function to deal with a wide range of challenges related to development and organogenesis, tissue injury, malignancy, sterile or pathogenic inflammatory stimuli. These stimuli alter gene expression to produce activated macrophages that are better equipped to eliminate the cause of their influx, and to restore homeostasis. Activation or polarization states of macrophages have been classified as classical and alternative or M1 and M2. These proposed states of cells are not supported by large-scale transcriptomic data, including macrophage-associated signatures from large cancer tissue datasets, where the supposed markers do not correlate with other. Individual macrophage cells differ markedly from each other, and change their functions in response to doses and combinations of agonists and time. The most studied macrophage activation response is the transcriptional cascade initiated by the TLR4 agonist lipopolysaccharide (LPS). This response is reviewed herein. The network architecture is conserved across species, but many of the target genes evolve rapidly and differ between mouse and human. There is also considerable divergence in the sets of target genes between mouse strains, between individuals and in other species such as pigs. The data and publication deluge related to macrophage activation requires the development of new analytical tools, and ways of presenting information in an accessibl

    The Diverse Function of Macrophages in Renal Disease

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    Experimental and human studies indicate that macrophages play a key role within the diseased kidney and represent a target for novel therapies. This brief review outlines the involvement and nature of macrophages in renal disease and highlights the phenotypic plasticity of these cells and their responsiveness to the renal microenvironment

    Cytochalasin B-induced membrane vesicles convey angiogenic activity of parental cells

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    Naturally occurring extracellular vesicles (EVs) play essential roles in intracellular communication and delivery of bioactive molecules. Therefore it has been suggested that EVs could be used for delivery of therapeutics. However, to date the therapeutic application of EVs has been limited by number of factors, including limited yield and full understanding of their biological activities. To address these issues, we analyzed the morphology, molecular composition, fusion capacity and biological activity of Cytochalasin B-induced membrane vesicles (CIMVs). The size of these vesicles was comparable to that of naturally occurring EVs. In addition, we have shown that CIMVs from human SH-SY5Y cells contain elevated levels of VEGF as compared to the parental cells, and stimulate angiogenesis in vitro and in vivo

    Detected fluctuations in SDSS LRG magnitudes: Bulk flow signature or systematic?

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    In this paper we search for a signature of a large scale bulk flow by looking for fluctuations in the magnitudes of distant LRGs. We take a sample of LRGs from the Sloan Digital Sky Survey with redshifts of z>0.08 over a contiguous area of sky. Neighboring LRG magnitudes are averaged together to find the fluctuation in magnitudes as a function of R.A.. The result is a fluctuation of a few percent in flux across roughly 100 degrees. The source of this fluctuation could be from a large scale bulk flow or a systematic in our treatment of the data set, or the data set itself. A bulk flow model is fitted to the observed fluctuation, and the three bulk flow parameters, its direction and magnitude: alpha_b, delta_b, v_b are constrained. We find that the bulk flow direction is consistent with the direction found by other authors, with alpha_b 180, delta_b -50. The bulk flow magnitude however was found to be anomalously large with v_b>4000km/s. The LRG angular selection function cannot be sufficiently taken into account in our analysis with the available data, and may be the source of either the anomalous magnitude of the bulk flow signal, or possibly the entire fluctuation. However, the fluctuation indicates a bulk flow direction very close to those found using other data sets and analyses. Further investigation with upcoming data is required to confirm this detection.Comment: 10 pages, 7 figures, 1 table. V2: citations added to the introduction and a paragraph to the discussion. V3: Accepted by MNRAS. 1 figure, additional clarifications, discussion and references adde
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