248 research outputs found
Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at TeV
Inclusive transverse momentum spectra of primary charged particles in Pb-Pb
collisions at = 2.76 TeV have been measured by the ALICE
Collaboration at the LHC. The data are presented for central and peripheral
collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross
section. The measured charged particle spectra in and GeV/ are compared to the expectation in pp collisions at the same
, scaled by the number of underlying nucleon-nucleon
collisions. The comparison is expressed in terms of the nuclear modification
factor . The result indicates only weak medium effects ( 0.7) in peripheral collisions. In central collisions,
reaches a minimum of about 0.14 at -7GeV/ and increases
significantly at larger . The measured suppression of high- particles is stronger than that observed at lower collision energies,
indicating that a very dense medium is formed in central Pb-Pb collisions at
the LHC.Comment: 15 pages, 5 captioned figures, 3 tables, authors from page 10,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/98
Two-pion Bose-Einstein correlations in central Pb-Pb collisions at = 2.76 TeV
The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb
collisions at TeV at the Large Hadron Collider is
presented. We observe a growing trend with energy now not only for the
longitudinal and the outward but also for the sideward pion source radius. The
pion homogeneity volume and the decoupling time are significantly larger than
those measured at RHIC.Comment: 17 pages, 5 captioned figures, 1 table, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/388
The influence of blood on the efficacy of intraperitoneally applied phospholipids for prevention of adhesions
<p>Abstract</p> <p>Background</p> <p>The formation of adhesions following abdominal surgery is a well known problem. In previous studies we demonstrated the efficacy and safety of intraperitoneally applied phospholipids in order to prevent adhesion formation. This study evaluates the influence of blood on the efficacy of intraperitoneally applied phospholipids for prevention of adhesions.</p> <p>Methods</p> <p>In 40 Chinchilla rabbits adhesions were induced by median laparotomy, standardized abrasion of the visceral and parietal peritoneum in defined areas of the ventral abdominal wall and the caecum. The animals were randomly divided into four groups. They received either phospholipids 3.0% or normal saline (NaCl 0,9%) (5 ml/kg body weight). In 50% of the rabbits we simulated intraperitoneal bleeding by administration of blood (1,5 ml/kg body weight). The other half served as control group. Ten days following the operation the animals were sacrificed and adhesion formation was assessed by computer aided planimetry and histopathologic examination.</p> <p>Results</p> <p>The median adhesion surface area in the NaCl-group (n = 9) amounted to 68,72 mm<sup>2</sup>, in the NaCl+Blood-group (n = 10) 147,68 mm<sup>2</sup>. In the Phospholipid (PhL)-group (n = 9) the median adhesion surface area measured 9,35 mm<sup>2</sup>, in the PhL+Blood-group (n = 9) 11,95 mm<sup>2</sup>. The phospholipid groups had a significantly smaller adhesion surface area (p < 0.05).</p> <p>Conclusion</p> <p>Again these results confirm the efficacy of phospholipids in the prevention of adhesions in comparison to NaCl (p = 0,04). We also demonstrated the adhesion preventing effect of phospholipids in the presence of intraperitoneal blood.</p
Azimuthal anisotropy and correlations at large transverse momenta in and Au+Au collisions at = 200 GeV
Results on high transverse momentum charged particle emission with respect to
the reaction plane are presented for Au+Au collisions at =
200 GeV. Two- and four-particle correlations results are presented as well as a
comparison of azimuthal correlations in Au+Au collisions to those in at
the same energy. Elliptic anisotropy, , is found to reach its maximum at
GeV/c, then decrease slowly and remain significant up to
-- 10 GeV/c. Stronger suppression is found in the back-to-back
high- particle correlations for particles emitted out-of-plane compared to
those emitted in-plane. The centrality dependence of at intermediate
is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004
Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV
The results from the STAR Collaboration on directed flow (v_1), elliptic flow
(v_2), and the fourth harmonic (v_4) in the anisotropic azimuthal distribution
of particles from Au+Au collisions at sqrtsNN = 200 GeV are summarized and
compared with results from other experiments and theoretical models. Results
for identified particles are presented and fit with a Blast Wave model.
Different anisotropic flow analysis methods are compared and nonflow effects
are extracted from the data. For v_2, scaling with the number of constituent
quarks and parton coalescence is discussed. For v_4, scaling with v_2^2 and
quark coalescence is discussed.Comment: 26 pages. As accepted by Phys. Rev. C. Text rearranged, figures
modified, but data the same. However, in Fig. 35 the hydro calculations are
corrected in this version. The data tables are available at
http://www.star.bnl.gov/central/publications/ by searching for "flow" and
then this pape
Rapidity and Centrality Dependence of Proton and Anti-proton Production from Au+Au Collisions at sqrt(sNN) = 130GeV
We report on the rapidity and centrality dependence of proton and anti-proton
transverse mass distributions from Au+Au collisions at sqrt(sNN) = 130GeV as
measured by the STAR experiment at RHIC. Our results are from the rapidity and
transverse momentum range of |y|<0.5 and 0.35 <p_t<1.00GeV/c. For both protons
and anti-protons, transverse mass distributions become more convex from
peripheral to central collisions demonstrating characteristics of collective
expansion. The measured rapidity distributions and the mean transverse momenta
versus rapidity are flat within |y|<0.5. Comparisons of our data with results
from model calculations indicate that in order to obtain a consistent picture
of the proton(anti-proton) yields and transverse mass distributions the
possibility of pre-hadronic collective expansion may have to be taken into
account.Comment: 4 pages, 3 figures, 1 table, submitted to PR
Gender Nonconformity During Adolescence:Links with Stigma, Sexual Minority Status, and Psychosocial Outcomes
Both gender nonconformity and sexual minority status during adolescence are associated with elevated levels of victimization and harassment, experiences that have serious consequences for adolescent psychosocial outcomes. While gender nonconformity and sexual minority status reflect separate constructs, they are associated because (1) sexual minority youth report higher levels of gender nonconformity and (2) gender nonconformity is frequently used to attribute sexual minority status by others. Following from classic stigma theory, the current chapter focuses on the role of gender nonconformity in explaining variation in social exclusion and victimization among both sexual minority and sexual majority youth. Of particular interest is the potential for gender nonconformity to mediate or moderate the association between sexual minority status and individual mental health and wellbeing outcomes. Gender differences will also be discussed, focusing on differences between girls and boys in the links between sexual minority status, gender nonconformity, experiences of victimization, and negative psychosocial outcomes. Additionally, the emerging literature on conceptualizing gender nonconformity among trans and non-binary youth will be addressed. Finally, the current chapter will finish with a discussion of how and why gender nonconformity must be taken into consideration in the development of programs aimed at reducing homophobia among adolescent populations
New roles for renin and prorenin in heart failure and cardiorenal crosstalk
The renin-angiotensin-aldosterone-system (RAAS) plays a central role in the pathophysiology of heart failure and cardiorenal interaction. Drugs interfering in the RAAS form the pillars in treatment of heart failure and cardiorenal syndrome. Although RAAS inhibitors improve prognosis, heart failure–associated morbidity and mortality remain high, especially in the presence of kidney disease. The effect of RAAS blockade may be limited due to the loss of an inhibitory feedback of angiotensin II on renin production. The subsequent increase in prorenin and renin may activate several alternative pathways. These include the recently discovered (pro-) renin receptor, angiotensin II escape via chymase and cathepsin, and the formation of various angiotensin subforms upstream from the blockade, including angiotensin 1–7, angiotensin III, and angiotensin IV. Recently, the direct renin inhibitor aliskiren has been proven effective in reducing plasma renin activity (PRA) and appears to provide additional (tissue) RAAS blockade on top of angiotensin-converting enzyme and angiotensin receptor blockers, underscoring the important role of renin, even (or more so) under adequate RAAS blockade. Reducing PRA however occurs at the expense of an increase plasma renin concentration (PRC). PRC may exert direct effects independent of PRA through the recently discovered (pro-) renin receptor. Additional novel possibilities to interfere in the RAAS, for instance using vitamin D receptor activation, as well as the increased knowledge on alternative pathways, have revived the question on how ideal RAAS-guided therapy should be implemented. Renin and prorenin are pivotal since these are at the base of all of these pathways
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