915 research outputs found
Transverse momentum dependence of semi-inclusive pion production
Cross sections for semi-inclusive electroproduction of charged pions
() from both proton and deuteron targets were measured for
, GeV, , and GeV. For
GeV, we find the azimuthal dependence to be small, as expected
theoretically. For both and , the dependence from the
deuteron is found to be slightly weaker than from the proton. In the context of
a simple model, this implies that the initial transverse momenta width of
quarks is larger than for quarks and, contrary to expectations, the
transverse momentum width of the favored fragmentation function is larger than
the unfavored one.Comment: 15 pages, 4 figures. Fit form changed to include Cahn effect Minor
revisions. Added one new figur
The Onset of Quark-Hadron Duality in Pion Electroproduction
A large data set of charged-pion electroproduction from both hydrogen and
deuterium targets has been obtained spanning the low-energy residual-mass
region. These data conclusively show the onset of the quark-hadron duality
phenomenon, as predicted for high-energy hadron electroproduction. We construct
several ratios from these data to exhibit the relation of this phenomenon to
the high-energy factorization ansatz of electron-quark scattering and
subsequent quark-to- pion production mechanisms.Comment: 11 pages, 3 figures, accepted in Phys. Rev. Lett. Tables adde
MitoQ improves mitochondrial dysfunction in heart failure induced by pressure overload.
Heart failure remains a major public-health problem with an increase in the number of patients worsening from this disease. Despite current medical therapy, the condition still has a poor prognosis. Heart failure is complex but mitochondrial dysfunction seems to be an important target to improve cardiac function directly. Our goal was to analyze the effects of MitoQ (100 µM in drinking water) on the development and progression of heart failure induced by pressure overload after 14 weeks. The main findings are that pressure overload-induced heart failure in rats decreased cardiac function in vivo that was not altered by MitoQ. However, we observed a reduction in right ventricular hypertrophy and lung congestion in heart failure animals treated with MitoQ. Heart failure also decreased total mitochondrial protein content, mitochondrial membrane potential in the intermyofibrillar mitochondria. MitoQ restored membrane potential in IFM but did not restore mitochondrial protein content. These alterations are associated with the impairment of basal and stimulated mitochondrial respiration in IFM and SSM induced by heart failure. Moreover, MitoQ restored mitochondrial respiration in heart failure induced by pressure overload. We also detected higher levels of hydrogen peroxide production in heart failure and MitoQ restored the increase in ROS production. MitoQ was also able to improve mitochondrial calcium retention capacity, mainly in the SSM whereas in the IFM we observed a small alteration. In summary, MitoQ improves mitochondrial dysfunction in heart failure induced by pressure overload, by decreasing hydrogen peroxide formation, improving mitochondrial respiration and improving mPTP opening
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Identifying the physical features of marina infrastructure associated with the presence of non-native species in the UK
Marine invasive non-native species (NNS) are one of the greatest threats to global marine biodiversity, causing significant economic and social impacts. Marinas are increasingly recognised as key reservoirs for invasive NNS. They provide submersed artificial habitat that unintentionally supports the establishment of NNS introduced from visiting recreational vessels. While ballast water and shipping vectors have been well documented, the role of recreational vessels in spreading NNS has been relatively poorly studied. Identification of the main physical features found within marinas, which relate to the presence of NNS, is important to inform the development of effective biosecurity measures and prevent further spread. Towards this aim, physical features that could influence the presence of NNS were assessed for marinas throughout the UK in July 2013. Thirty-three marine and brackish NNS have been recorded in UK marinas, and of the 88 marinas studied in detail, 83 contained between 1 and 13 NNS. Significant differences in freshwater input, marina entrance width and seawall length were associated with the presence of NNS. Additionally, questionnaires were distributed to marina managers and recreational vessel owners to understand current biosecurity practices and attitudes to recreational vessel biosecurity. The main barriers to biosecurity compliance were cited as cost and time. Further work identifying easily distinguished features of marinas could be used as a proxy to assess risk of invasion. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00227-016-2941-8) contains supplementary material, which is available to authorized users
Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer
The differential cross-section for the process p(e,e'p)eta has been measured
at Q2 ~ 5.7 and 7.0 (GeV/c)2 for centre-of-mass energies from threshold to 1.8
GeV, encompassing the S11(1535) resonance, which dominates the channel. This is
the highest momentum transfer measurement of this exclusive process to date.
The helicity-conserving transition amplitude A_1/2, for the production of the
S11(1535) resonance, is extracted from the data. Within the limited Q2 now
measured, this quantity appears to begin scaling as 1/Q3 - a predicted, but not
definitive, signal of the dominance of perturbative QCD, at Q2 ~ 5 (GeV/c)2.Comment: LaTeX, 30 pages, 29 figures, uses longtable.sty, slashbox.sty,
ifthen.sty; (v2) corrected figure inclusions; (v3) changes in filenames for
prc and added Report-no; (v4) correction based on comments from referee
{small changes to abstract and conclusion, inserted figure 9, other small
changes to the text} (v5) very minor additions to improve clarit
Measurement of exclusive pion pair production in proton–proton collisions at √s=7 TeV with the ATLAS detector
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