Observation of direct-photon collective flow in Au + Au collisions at √s(NN)] = 200 GeV

The second Fourier component v(2) of the azimuthal anisotropy with respect to the reaction plane is measured for direct photons at midrapidity and transverse momentum (p(T)) of 1-12 GeV/c in Au + Au collisions at √s(NN)] = 200 GeV. Previous measurements of this quantity for hadrons with p(T) < 6 GeV/c indicate that the medium behaves like a nearly perfect fluid, while for p(T) > 6 GeV/c a reduced anisotropy is interpreted in terms of a path-length dependence for parton energy loss. In this measurement with the PHENIX detector at the Relativistic Heavy Ion Collider we find that for p(T) > 4 GeV/c the anisotropy for direct photons is consistent with zero, which is as expected if the dominant source of direct photons is initial hard scattering. However, in the p(T) < 4 GeV/c region dominated by thermal photons, we find a substantial direct-photon v(2) comparable to that of hadrons, whereas model calculations for thermal photons in this kinematic region underpredict the observed v(2).

Production of muons from heavy flavor decays at forward rapidity in pp and Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV

The ALICE Collaboration has measured the inclusive production of muons from heavy-flavor decays at forward rapidity, 2.5<y<4, in pp and Pb-Pb collisions at sqrt[s(NN)]=2.76  TeV. The p(t)-differential inclusive cross section of muons from heavy-flavor decays in pp collisions is compared to perturbative QCD calculations. The nuclear modification factor is studied as a function of p(t) and collision centrality. A weak suppression is measured in peripheral collisions. In the most central collisions, a suppression of a factor of about 3-4 is observed in 6<p(t)<10  GeV/c. The suppression shows no significant p(t) dependence.

J/ψ suppression at forward rapidity in Pb-Pb collisions at √s(NN) = 2.76 TeV

The ALICE experiment has measured the inclusive J/ψ production in Pb-Pb collisions at √s(NN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/ψ yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545 ± 0.032(stat) ± 0.083(syst) and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/ψ production from charm quarks in a deconfined partonic phase can describe our data.

Particle-yield modification in jetlike azimuthal dihadron correlations in Pb-Pb collisions at √s(NN)=2.76 TeV

The yield of charged particles associated with high-p(t) trigger particles (8<p(t)<15 GeV/c) is measured with the ALICE detector in Pb-Pb collisions at √s(NN)=2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jetlike correlation peaks in azimuthal dihadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta p(t)>3 GeV/c on the away side drops to about 60% of that observed in pp collisions, while on the near side a moderate enhancement of 20%-30% is found.

J/ψ polarization in pp collisions at √s=7 TeV

The ALICE Collaboration has studied J/ψ production in pp collisions at √s=7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/ψ polarization parameters λ(θ) and λ(φ) were obtained. The study was performed in the kinematic region 2.5<y<4, 2<p(t)<8 GeV/c, in the helicity and Collins-Soper reference frames. In both frames, the polarization parameters are compatible with zero, within uncertainties.

Extracorporeal membrane oxygenation following pediatric cardiac surgery: development and outcomes from a single-center experience

Extracorporeal membrane oxygenation (ECMO) has emerged as an effective mechanical support following cardiac surgery with respiratory and cardiac failure. However, there are no clear indications for ECMO use after pediatric cardiac surgery. We retrospectively reviewed medical records of 76 pediatric patients [mean age, 10.8 months (0–86); mean weight, 5.16 kg (1.16–16.5)] with congenital heart disease who received ECMO following cardiac surgery between January 1997 and October 2010. Forty-five patients were treated with an aggressive ECMO approach (aggressive ECMO group, April 2005–October 2010) and 31 with a delayed ECMO approach (delayed ECMO group, January 1997–March 2005). Demographics, diagnosis, operative variables, ECMO indication, and duration of survivors and non-survivors were compared. Thirty-four patients (75.5%) were successfully weaned from ECMO in the aggressive ECMO group and 26 (57.7%) were discharged. Conversely, eight patients (25.8%) were successfully weaned from ECMO in the delayed ECMO group and two (6.5%) were discharged. Forty-five patients with shunted single ventricle physiology (aggressive: 29 patients, delayed: 16 patients) received ECMO, but only 15 (33.3%) survived and were discharged. The survival rate of the aggressive ECMO group was significantly better when compared with the delayed ECMO group (p<0.01). Also, ECMO duration was significantly shorter among the aggressive ECMO group survivors (96.5 ± 62.9 h, p<0.01). Thus, the aggressive ECMO approach is a superior strategy compared to the delayed ECMO approach in pediatric cardiac patients. The aggressive ECMO approach improved our outcomes of neonatal and pediatric ECMO.

Carbenoxolone alters the morphology of adipose tissues and downregulates genes involved in adipogenesis, glucose transport and lipid metabolism in high-fat diet-fed mice

Glucocorticoid (GC) excess promotes adipose tissue accumulation, and 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) plays an important role in the local amplification of GC. Therefore, in this study, we investigated the effects of carbenoxolone (CBX), an 11β-HSD1 inhibitor, on morphological changes in visceral fat, and the expression of genes involved in adipogenesis and lipid metabolism in high-fat (HF) diet-fed mice. Mice were fed a HF diet from 5 weeks of age. At 10 weeks of age, the mice received an intraperitoneal injection of CBX or vehicle every day for 2 weeks. CBX decreased body weight and visceral fat mass, and improved insulin sensitivity in HF-fed mice. This was accompanied by reduced adipocyte size and a decrease in large-sized adipocytes in visceral fat. The expression of adipogenesis (PPARγ and C/EBPα), glucose transport (GLUT4) and lipid metabolism (LPL, ATGL, and HSL)-related genes were suppressed in CBX mice. CBX treatment induced beneficial morphological changes in visceral fat and decreased the expression of adipogenesis, glucose transport and lipid metabolism-related genes. These findings reveal a potential mechanism underling the effects of CBX on reduced fat accumulation and improved insulin sensitivity.

Measurements of higher order flow harmonics in Au+Au collisions at √s(NN)=200 GeV

Flow coefficients ν(n) for n=2, 3, 4, characterizing the anisotropic collective flow in Au+Au collisions at √s(NN)=200 GeV, are measured relative to event planes Ψ(n), determined at large rapidity. We report ν(n) as a function of transverse momentum and collision centrality, and study the correlations among the event planes of different order n. The ν(n) are well described by hydrodynamic models which employ a Glauber Monte Carlo initial state geometry with fluctuations, providing additional constraining power on the interplay between initial conditions and the effects of viscosity as the system evolves. This new constraint can serve to improve the precision of the extracted shear viscosity to entropy density ratio η/s.

Diminished regulatory T cells in cutaneous lesions of thymoma-associated multi-organ autoimmunity: a newly described paraneoplastic autoimmune disorder with fatal clinical course

Thymoma-associated multi-organ autoimmunity is a rare, autoimmune disease that causes colitis, liver dysfunction and cutaneous graft-versus-host (GVH)-like skin damage. This paraneoplastic autoimmune disorder may be due to inadequate T cell selection in the tumour environment of the thymus. Although sporadic case reports have revealed its clinical features, little is known about its pathological mechanism. By comparing the skin-infiltrating T cell subsets with those of GVH disease (GVHD) and other inflammatory skin diseases, we sought to elucidate the pathological mechanism of thymoma-associated multi-organ autoimmunity. Histopathological and immunohistochemical analysis of skin biopsies was performed for three patients with thymoma-associated multi-organ autoimmunity. Histopathological findings of thymoma-associated multi-organ autoimmunity were indistinguishable from those of patients with acute GVHD, although the aetiologies of these diseases are completely different. The frequency of regulatory T cells (T(regs)) is reduced in cutaneous lesions and CD8+ cytotoxic T lymphocytes that massively infiltrate into the epidermis of patients with thymoma-associated multi-organ autoimmunity. Additionally, the ratio of T helper type 17 (Th17) cells to CD4+ cells in patients with thymoma-associated multi-organ autoimmunity and acute GVHD was higher than that in healthy controls, but similar to that in psoriasis vulgaris patients. Similarity of the skin-infiltrating T cell subsets with those of acute GVHD suggested that skin damage in patients with thymoma-associated multi-organ autoimmunity might be induced by self-reactive cytotoxic T lymphocytes under the diminished suppressive capacity of T(regs).

Suppression of back-to-back hadron pairs at forward rapidity in d+Au collisions at √s(NN)=200 GeV

Back-to-back hadron pair yields in d+Au and p+p collisions at √s(NN)=200 GeV were measured with the PHENIX detector at the Relativistic Heavy Ion Collider. Rapidity separated hadron pairs were detected with the trigger hadron at pseudorapidity |η|<0.35 and the associated hadron at forward rapidity (deuteron direction, 3.0<η<3.8). Pairs were also detected with both hadrons measured at forward rapidity; in this case, the yield of back-to-back hadron pairs in d+Au collisions with small impact parameters is observed to be suppressed by a factor of 10 relative to p+p collisions. The kinematics of these pairs is expected to probe partons in the Au nucleus with a low fraction x of the nucleon momenta, where the gluon densities rise sharply. The observed suppression as a function of nuclear thickness, p(T), and η points to cold nuclear matter effects arising at high parton densities.

Reinvestigation of the synthesis of isoliquiritigenin: application of Horner-Wadsworth-Emmons reaction and Claisen-Schmidt condensation

Isoliquiritigenin [ILG, (E)-1] was readily prepared via the Horner-Wadsworth-Emmons reactions using β-ketophosphonates 5a, b. An improved protocol for the synthesis of (E)-1 via the Claisen-Schmidt condensation was also presented.

Pediatric perfusion in Japan: 2010 practice survey

We report here Japan’s first pediatric perfusion survey. It covers practices from January 2007 through December 2009. Of the 70 congenital heart centers contacted, 53 (76%) completed the survey. They reported performing 3,379 pediatric cardiopulmonary bypass (CPB) procedures in 2009, 3,408 in 2008, and 3,358 in 2007.Twenty-eight percent of all centers used CPB circuits with a priming volume between 151-200 ml. All centers used pre-bypass ultrafiltration and only 6% used retrograde autologous priming. A biomaterial-coated circuit was used by 78% of the centers, a roller pump as the arterial pump by 91%, vacuum-assisted venous drainage by 39%, dilutional ultrafiltration by 48%, and modified ultrafiltration at the end of the procedure by 30%. A regional oxygen saturation monitor was used by 69% of the centers and high flow (150-200 ml/kg/min) management with alpha-stat blood gas control was standard during moderate to normothermic CPBs. Crystalloid cardioplegia solution was used as myocardial protection by 56% of the centers, electronic recording of monitoring data by 51%. The centers performed 98 pediatric extracorporeal membrane oxygenation procedures in 2007, 109 in 2008, and 119 in 2009; 58% of the centers used a centrifugal pump. This survey provides a description of the current practice in Japan. Future surveys will identify trends and rate of change in practice.

Cold nuclear matter effects on J/ψ yields as a function of rapidity and nuclear geometry in d+A collisions at sqrt[s(NN)]=200 GeV

We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200  GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2<y<2.4) with high statistical precision and are compared with two theoretical models: one with nuclear shadowing combined with final state breakup and one with coherent gluon saturation effects. In order to remove model dependent systematic uncertainties we also compare the data to a simple geometric model. The forward rapidity data are inconsistent with nuclear modifications that are linear or exponential in the density weighted longitudinal thickness, such as those from the final state breakup of the bound state.

Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at sqrt(s(NN)) = 2.76  TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

Altered gene expressions of ghrelin, PYY, and CCK in the gastrointestinal tract of the hyperphagic intrauterine growth restriction rat offspring

Intrauterine growth restriction (IUGR) is associated with a substantially greater incidence of metabolic syndrome in adulthood. Animal studies have shown that IUGR offspring are hyperphagic during the early postnatal period and therefore exhibit obesity. The molecular mechanisms underlying food intake regulation in the gastrointestinal tract have not been clarified in IUGR. In the present study, we utilized a rat model of IUGR by restricting the food intake of the mother (50% of the normal intake, ad libitum; FR group) from day 7 of gestation until delivery. Pups from undernourished mothers were fostered by control mothers. We examined the food intake and assessed the gene expressions of ghrelin, peptide YY (PYY), and cholecystokinin (CCK) in the alimentary tract of male newborns (postnatal day1) and adult offspring (age, 7 months). Compared to the offspring whose mothers received the standard diet ad libitum (CON offspring), FR offspring were hyperphagic from the weaning time until the end of the experiment, and resulted in a heavier final weight. Both newborn and adult FR offspring had higher ghrelin gene expression in the stomach and higher ghrelin plasma levels than did the controls. Although the gastrointestinal gene expressions and plasma levels of the anorexic peptides, PYY and CCK, were elevated in the FR newborns, they decreased in the FR adults. Our findings suggest that the altered gene expressions of orexigenic and anorexigenic gut peptides in the gastrointestinal tract in the maternal undernutrition-induced IUGR offspring provide a potential mechanism to explain hyperphagia and obesity seen in these offspring.

Cross section and parity-violating spin asymmetries of W± boson production in polarized p + p collisions at sqrt[s] = 500 GeV

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = -0.86(-0.14) (+0.30) and A(L)(e-) = 0.88(-0.71) (+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p+p collisions at a center-of-mass energy of sqrt[s] = 500 GeV with the PHENIX detector at RHIC. These e± come mainly from the decay of W± and Z0 bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W± to the light quarks. The observed electron and positron yields were used to estimate W± boson production cross sections for the e± channels of σ(pp → W+ X) × BR(W+ → e+ ν(e)) = 144.1 ± 21.2(stat)(-10.3) (+3.4) (syst) ± 21.6(norm)  pb, and σ(pp → W- X) × BR(W- → e- ν[over ¯](e)) = 31.7 ± 12.1(stat)(-8.2) (+10.1) (syst) ± 4.8(norm)  pb.

Centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

The centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor of 2 from peripheral (70%-80%) to central (0%-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions.

Elliptic flow of charged particles in Pb-Pb collisions at sqrt[S(NN)] = 2.76 TeV

We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2<p t<5.0 GeV/c. The elliptic flow signal v₂, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087 ± 0.002(stat) ± 0.003(syst) in the 40%-50% centrality class. The differential elliptic flow v₂ p t reaches a maximum of 0.2 near p t =3 GeV/c. Compared to RHIC Au-Au collisions at sqrt[S(NN)] 200 GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase.

Charged-particle multiplicity density at midrapidity in central Pb-Pb collisions at sqrt[S(NN)] = 2.76 TeV

The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies.