4,197 research outputs found
Solar cycle variation in solar f-mode frequencies and radius
Using data from the Global Oscillation Network Group (GONG) covering the
period from 1995 to 1998, we study the change with solar activity in solar
f-mode frequencies. The results are compared with similar changes detected from
the Michelson Doppler Imager (MDI) data. We find variations in f-mode
frequencies which are correlated with solar activity indices. If these changes
are due to variation in solar radius then the implications are that the solar
radius decreases by about 5 km from minimum to maximum activity.Comment: To appear in Solar Physic
TERC polymorphisms are associated both with susceptibility to colorectal cancer and with longer telomeres.
Shorter telomeres have been associated with increased risk of malignancy, including colorectal cancer (CRC). Telomere length is heritable and may be an intermediate phenotype linked to genetic susceptibility to CRC
Interleukin-33 regulates tissue remodelling and inhibits angiogenesis in the eye
Age-related macular degeneration (AMD) is the leading cause of central vision loss worldwide. Loss of retinal pigment epithelium (RPE) is a major pathological hallmark in AMD with or without pathological neovascularization. Although activation of the immune system is implicated in disease progression, pathological pathways remain diverse and unclear. Here, we report an unexpected protective role of a pro-inflammatory cytokine, interleukin-33 (IL-33) in ocular angiogenesis. IL-33 and its receptor (ST2) are expressed constitutively in human and murine retina and choroid. When RPE was activated, IL-33 expression was markedly elevated in vitro. We found that IL-33 regulated tissue remodelling by attenuating wound-healing responses, including reduction in migration of choroidal fibroblasts and retinal microvascular endothelial cells, and inhibition of collagen gel contraction. In vivo, local administration of recombinant IL-33 inhibited murine choroidal neovascularization (CNV) formation, a surrogate of human neovascular AMD, and this effect was ST2-dependent. Collectively, these data demonstrate IL-33 as a potential immunotherapy and distinguishes pathways for subverting AMD pathology
Two-neutron knockout from neutron-deficient Ar, S, and Si
Two-neutron knockout reactions from nuclei in the proximity of the proton
dripline have been studied using intermediate-energy beams of neutron-deficient
Ar, S, and Si. The inclusive cross sections, and also the
partial cross sections for the population of individual bound final states of
the Ar, S and Si knockout residues, have been determined
using the combination of particle and -ray spectroscopy. Similar to the
two-proton knockout mechanism on the neutron-rich side of the nuclear chart,
these two-neutron removal reactions from already neutron-deficient nuclei are
also shown to be consistent with a direct reaction mechanism.Comment: Phys. Rev. C, rapid communication, in pres
A survey of statistics in three UK general practice journal
Background
Many medical specialities have reviewed the statistical content of their journals. To our knowledge this has not been done in general practice. Given the main role of a general practitioner as a diagnostician we thought it would be of interest to see whether the statistical methods reported reflect the diagnostic process.
Methods
Hand search of three UK journals of general practice namely the British Medical Journal (general practice section), British Journal of General Practice and Family Practice over a one-year period (1 January to 31 December 2000).
Results
A wide variety of statistical techniques were used. The most common methods included t-tests and Chi-squared tests. There were few articles reporting likelihood ratios and other useful diagnostic methods. There was evidence that the journals with the more thorough statistical review process reported a more complex and wider variety of statistical techniques.
Conclusions
The BMJ had a wider range and greater diversity of statistical methods than the other two journals. However, in all three journals there was a dearth of papers reflecting the diagnostic process. Across all three journals there were relatively few papers describing randomised controlled trials thus recognising the difficulty of implementing this design in general practice
NLO Higgs boson production plus one and two jets using the POWHEG BOX, MadGraph4 and MCFM
We present a next-to-leading order calculation of Higgs boson production plus
one and two jets via gluon fusion interfaced to shower Monte Carlo programs,
implemented according to the POWHEG method. For this implementation we have
used a new interface of the POWHEG BOX with MadGraph4, that generates the codes
for generic Born and real processes automatically. The virtual corrections have
been taken from the MCFM code. We carry out a simple phenomenological study of
our generators, comparing them among each other and with fixed next-to-leading
order results.Comment: 27 pages, 21 figure
Automation of one-loop QCD corrections
We present the complete automation of the computation of one-loop QCD
corrections, including UV renormalization, to an arbitrary scattering process
in the Standard Model. This is achieved by embedding the OPP integrand
reduction technique, as implemented in CutTools, into the MadGraph framework.
By interfacing the tool so constructed, which we dub MadLoop, with MadFKS, the
fully automatic computation of any infrared-safe observable at the
next-to-leading order in QCD is attained. We demonstrate the flexibility and
the reach of our method by calculating the production rates for a variety of
processes at the 7 TeV LHC.Comment: 64 pages, 12 figures. Corrected the value of m_Z in table 1. In table
2, corrected the values of cross sections in a.4 and a.5 (previously computed
with mu=mtop/2 rather than mu=mtop/4). In table 2, corrected the values of
NLO cross sections in b.3, b.6, c.3, and e.7 (the symmetry factor for a few
virtual channels was incorrect). In sect. A.4.3, the labeling of the
four-momenta was incorrec
The Recognition of Excessive blood loss At ChildbirTh (REACT) Study: a twoâphase exploratory, sequential mixed methods inquiry using focus groups, interviews and a pilot, randomised crossover study
From Wiley via Jisc Publications RouterHistory: accepted 2021-04-16, pub-electronic 2021-05-27Article version: VoRPublication status: PublishedFunder: Research Trainees Coordinating Centre; Id: http://dx.doi.org/10.13039/501100000659; Grant(s): DRFâ2012â05â140Objectives: To explore how childbirthârelated blood loss is evaluated and excessive bleeding recognised; and to develop and test a theory of postpartum haemorrhage (PPH) diagnosis. Design: Twoâphase, exploratory, sequential mixed methods design using focus groups, interviews and a pilot, randomised crossover study. Setting: Two hospitals in North West England. Sample: Women (following vaginal birth with and without PPH), birth partners, midwives and obstetricians. Methods: Phase 1 (qualitative): 8 focus groups and 20 oneâtoâone, semiâstructured interviews were conducted with 15 women, 5 birth partners, 11 obstetricians, 1 obstetric anaesthetist and 19 midwives (n = 51). Phase 2 (quantitative): 11 obstetricians and ten midwives (n = 21) completed two simulations of fast and slow blood loss using a highâfidelity childbirth simulator. Results: Responses to blood loss were described as automatic, intuitive reactions to the speed, nature and visibility of blood flow. Health professionals reported that quantifying volume was most useful after a PPH diagnosis, to validate intuitive decisions and guide ongoing management. During simulations, PPH treatment was initiated at volumes at or below 200 ml (fast mean blood loss 79.6 ml, SD 41.1; slow mean blood loss 62.6 ml, SD 27.7). All participants treated fast, visible blood loss, but only half treated slow blood loss, despite there being no difference in volumes (difference 18.2 ml, 95% CI â5.6 to 42.2 ml, P = 0.124). Conclusions: Experience and intuition, rather than blood loss volume, inform recognition of excessive blood loss after birth. Women and birth partners want more information and open communication about blood loss. Further research exploring clinical decisionâmaking and how to support it is required. Tweetable abstract: During a PPH, clinical decisionâmaking is intuitive with clinicians treating as soon as excessive loss is recognised
Molecular Evolutionary Characterization of a V1R Subfamily Unique to Strepsirrhine Primates
Vomeronasal receptor genes have frequently been invoked as integral to the establishment and maintenance of species boundaries among mammals due to the elaborate one-to-one correspondence between semiochemical signals and neuronal sensory inputs. Here, we report the most extensive sample of vomeronasal receptor class 1 (V1R) sequences ever generated for a diverse yet
phylogenetically coherent group of mammals, the tooth-combed primates (suborder Strepsirrhini). Phylogenetic analysis confirms our intensive sampling from a single V1R subfamily, apparently unique to the strepsirrhine primates. We designate this subfamily as V1Rstrep. The subfamily retains extensive repertoires of gene copies that descend from an ancestral gene duplication that appears to have occurred prior to the diversification of all lemuriform primates excluding the basal genusDaubentonia (the aye-aye). We refer to the descendent clades as V1Rstrep-a and V1Rstrep-b. Comparison of the two clades reveals different amino acid compositions corresponding to the predicted ligand-binding site and thus potentially to altered functional profiles between the two. In agreement with previous studies of the mouse lemur (genus, Microcebus), the majority of V1Rstrep gene copies appear to be intact and under strong positive selection, particularly within transmembrane regions. Finally, despite the surprisingly high number of gene copies identified in this study, it is nonetheless probable that V1R diversity remains underestimated in these nonmodel primates and that
complete characterization will be limited until high-coverage assembled genomes are available
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