Parton Distributions in the Valon Model

The parton distribution functions determined by CTEQ at low $Q^2$ are used as inputs to test the validity of the valon model. The valon distributions in a nucleon are first found to be nearly $Q$ independent. The parton distribution in a valon are shown to be consistent with being universal, independent of the valon type. The momentum fractions of the partons in the valon add up separately to one. These properties affirm the validity of the valon model. The various distributions are parameterized for convenient application of the model.Comment: 9 pages + 9 figures in ep

Serum hepatocyte growth factor is associated with small vessel disease in Alzheimer's dementia

Background: While hepatocyte growth factor (HGF) is known to exert cell growth, migration and morphogenic effects in various organs, recent studies suggest that HGF may also play a role in synaptic maintenance and cerebrovascular integrity. Although increased levels of HGF have been reported in brain and cerebrospinal fluid (CSF) samples of patients with Alzheimer's disease (AD), it is unclear whether peripheral HGF may be associated with cerebrovascular disease (CeVD) and dementia. In this study, we examined the association of baseline serum HGF with neuroimaging markers of CeVD in a cohort of pre-dementia (cognitive impaired no dementia, CIND) and AD patients. Methods: Serum samples from aged, Non-cognitively impaired (NCI) controls, CIND and AD subjects were measured for HGF levels. CeVD (cortical infarcts, microinfarcts, lacunes, white matter hyperintensities (WMH) and microbleeds) were assessed by magnetic resonance imaging (MRI). Results: After controlling for covariates, higher levels of HGF were associated with both CIND and AD. Among the different CeVD MRI markers in CIND and AD, only small vessel disease, but not large vessel disease markers were associated with higher HGF levels. Conclusion: Serum HGF may be a useful peripheral biomarker for small vessel disease in subjects with cognitive impairment and AD

B Production Asymmetries in Perturbative QCD

This paper explores a new mechanism for B production in which a b quark combines with a light parton from the hard-scattering process before hadronizing into the B hadron. This recombination mechanism can be calculated within perturbative QCD up to a few nonperturbative constants. Though suppressed at large transverse momentum by a factor Lambda_QCD m_b/p_t^2 relative to b quark fragmentation production, it can be important at large rapidities. A signature for this heavy-quark recombination mechanism in proton-antiproton colliders is the presence of rapidity asymmetries in B cross sections. Given reasonable assumptions about the size of nonperturbative parameters entering the calculation, we find that the asymmetries are only significant for rapidities larger than those currently probed by collider experiments.Comment: 17 pages, LaTeX, 4 ps figures, tightenlines, sections added, final version accepted for publication in Phys. Rev.

Serum IL-8 is a marker of white-matter hyperintensities in patients with Alzheimer's disease

Introduction Neuroinflammation and cerebrovascular disease (CeVD) have been implicated in cognitive impairment and Alzheimer's disease (AD). The present study aimed to examine serum inflammatory markers in preclinical stages of dementia and in AD, as well as to investigate their associations with concomitant CeVD. Methods We performed a cross-sectional case–control study including 96 AD, 140 cognitively impaired no dementia (CIND), and 79 noncognitively impaired participants. All subjects underwent neuropsychological and neuroimaging assessments, as well as collection of blood samples for measurements of serum samples interleukin (IL)-6, IL-8, and tumor necrosis factor α levels. Subjects were classified as CIND or dementia based on clinical criteria. Significant CeVD, including white-matter hyperintensities (WMHs), lacunes, and cortical infarcts, was assessed by magnetic resonance imaging. Results After controlling for covariates, higher concentrations of IL-8, but not the other measured cytokines, were associated with both CIND and AD only in the presence of significant CeVD (CIND with CeVD: odds ratios [ORs] 4.53; 95% confidence interval [CI] 1.5–13.4 and AD with CeVD: OR 7.26; 95% CI 1.2–43.3). Subsequent multivariate analyses showed that among the types of CeVD assessed, only WMH was associated with higher IL-8 levels in CIND and AD (WMH: OR 2.81; 95% CI 1.4–5.6). Discussion Serum IL-8 may have clinical utility as a biomarker for WMH in AD. Longitudinal follow-up studies would help validate these findings

Regional Multiple Pathology Scores Are Associated with Cognitive Decline in Lewy Body Dementias

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Hydrologic Modeling and Delineation of Calumpang River Watershed using GIS and Hydrologic Model System

The Calumpang Bridge in CALABARZON Region, Southern Luzon Philippines did not withstand the river current brought by Super Typhoon Glenda (Rammasun) on July 2014, causing the destruction of one-third of the bridge, thus resulting to traffic congestion and economic distress for the residents and businessmen. This paper aims to create a calibrated hydrological model. Specifically, it focuses on delineating watershed, simulation based on observed flow data and validation that will be the basis for flood risk map for the river. The watershed has been delineated and it is calibrated, the basin was modeled using Hydrologic Model System and GIS Applications to determine hydrologic parameters which have spatial characteristic and to compute the peak Discharge and loss infiltration. The model delineated by the use of GIS software has been hydrologically corrected. The model describes the correlation of the rainfall, losses, time of concentration, Storage factor and amount of discharge. It shows that the amount of Rainfall at a given time dictates the amount of discharge the watershed generates. The higher the rainfall amount, the higher the discharge. The model was validated using Percentage Error and Rational Method, and due to the accuracy of the validated model, it provides a promising approach to Bridge Structural Design and Flood Risk Map Generation

The bard−uˉbar{d} - \bar{u} asymmetry of the proton in a Pion Cloud Model approach

We study the $bar{d} - \bar{u}$ asymmetry of the proton in a model approach in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that the asymmetry of the proton is consistently described by including only nucleon fluctuations to $|\pi N>$ and $|\pi \Delta>$ bound states. Predictions of the model closely agree with the recent experimental data of the E866/NuSea Collaboration.Comment: Final version. To appear in Phys. Rev.

Flavor Decomposition of the Polarized Quark Distributions in the Nucleon from Inclusive and Semi-inclusive Deep-inelastic Scattering

Spin asymmetries of semi-inclusive cross sections for the production of positively and negatively charged hadrons have been measured in deep-inelastic scattering of polarized positrons on polarized hydrogen and 3He targets, in the kinematic range 0.023<x<0.6 and 1 GeV^2<Q^2<10 GeV^2. Polarized quark distributions are extracted as a function of x for up $(u+u_bar) and down (d+d_bar) flavors. The up quark polarization is positive and the down quark polarization is negative in the measured range. The polarization of the sea is compatible with zero. The first moments of the polarized quark distributions are presented. The isospin non-singlet combination Delta_q_3 is consistent with the prediction based on the Bjorken sum rule. The moments of the polarized quark distributions are compared to predictions based on SU(3)_f flavor symmetry and to a prediction from lattice QCD.Comment: 14 pages, 6 figures (eps format), 10 tables in Latex New version contains tables of asymmetries and correlation matri

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio