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.

SU-E-J-137: A Theoretical Model for the Analysis of Residual Motion Artifacts in 4D CT Scans

PURPOSE

The purpose of this study was to analysis the residual motion artifact in 4D-CT scan using a simple one-dimension theoretical model.

METHODS

In order to evaluate the target displacement at each phase image, We used phantom (Dynamic Thorax Phantom, CIRS, Norfolk, VA) which could control programmable regular 1D sine motion and belt type respiratory monitoring system. 2cm diameter spherical target was inserted in the phantom and then we set-up regular 1D sine motion and adjusted three level of amplitude (10, 20, 30 mm) with fixed period (4s). Four dimensional (4D) CT images were acquired by CT scanner (Sensation Open, Siemens Medical Systems, Forchheim, Germany) with a slice thickness of 1.5 mm and 0.1 pitch in helical mode. Respiratory monitoring system (AZ-733V, Anzai MEDICAL) was placed on the abdominal surface of phantom, and the respiratory signal was acquired. CorePLAN (RTP, SC&J) software was used to acquire static target diameter and each ten phase diameters.

RESULTS

The displacements (?S) peak at the 20∼30% or 70∼80% phases, and are minimized at the 50% phase. This is because the target velocity is minimum at 50% phase and maximum at 30 and 70% phases; hence, the large image blur. The measured diameters of target are compared to the simulation results and we observed similar trends of target diameter change.

CONCLUSIONS

In this study, we presented simple one-dimensional model to analyze the residual motion artifact in 4D-CT scan. The model was used to explain the effect of residual motion on each phase target displacement and also shown that residual motion artifact was affected that the target velocity at each phase. Lastly based on this model, we developed simulation program and acquired similar results of target displacement compared with measured data. This research was supported by Leading Foreign Re-search Institute Recruitment Program through the National Research Foundation of Korea (NFR) (Grant No. K20901000001-09E0100-00110,) and the program of Basic Atomic Energy Research Institute (BAERI) which is a part of the Nuclear R and D Programs (No.20110006324) funded by the Ministry of Education, Science and Technol-ogy(MEST).

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.

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.

Chronic insulin therapy reduces adipose tissue macrophage content in LDL-receptor-deficient mice

AIMS/HYPOTHESIS

Insulin has anti-inflammatory effects in short-term experiments. However, the effects of chronic insulin administration on inflammation are unknown. We hypothesised that chronic insulin administration would beneficially alter adipose tissue inflammation and several circulating inflammatory markers.

METHODS

We administered two forms of long-acting insulin, insulin glargine (A21Gly,B31Arg,B32Arg human insulin) and insulin detemir (B29Lys[ε-tetradecanoyl],desB30 human insulin), to LDL-receptor-deficient mice. After 8 weeks on a diet that causes obesity, hyperglycaemia, adipose tissue macrophage accumulation and atherosclerosis, the mice received subcutaneous glargine, detemir or NaCl (control) for 12 weeks. Serum amyloid A (SAA) and serum amyloid P (SAP), metabolic variables, adipose tissue macrophages and aortic atherosclerosis were evaluated.

RESULTS

Weight gain was equivalent in all groups. The glycated haemoglobin level fell equivalently in both insulin-treated groups. Plasma cholesterol and triacylglycerol levels, and hepatic triacylglycerol level significantly improved in the glargine compared with the detemir or control groups. Levels of mRNA expression for monocyte chemotactic protein-1 and F4/80, a macrophage marker, in adipose tissue were decreased only in the glargine group (p < 0.05). Visceral adipose tissue macrophage content decreased in both insulin groups (p < 0.05), whereas atherosclerosis decreased only in the glargine group. Circulating SAA and SAP did not decrease in either insulin-treated group, but IL-6 levels fell in the glargine-treated mice.

CONCLUSIONS/INTERPRETATION

While chronic insulin administration did not decrease SAA and SAP, administration of glargine but not detemir insulin improved dyslipidaemia, IL-6 levels and atherosclerosis, and both insulins reduced macrophage accumulation in visceral adipose tissue. Thus, chronic insulin therapy has beneficial tissue effects independent of circulating inflammatory markers in this murine model of diet-induced obesity and diabetes.

A hypoxia-dependent upregulation of hypoxia-inducible factor-1 by nuclear factor-κB promotes gastric tumour growth and angiogenesis

BACKGROUND

The underlying mechanisms involved in the activation of hypoxia-inducible factor-1 (HIF-1) in gastric cancer remain unclear. As nuclear factor-κB (NF-κB) as well as HIF-1 have been implicated in angiogenesis of various cancers, we investigated their relationship in gastric cancer.

METHODS

Nuclear expressions of HIF-1α and NF-κB/RelA were assessed in 251 human gastric carcinoma specimens by immunohistochemical tissue array analysis. Stable human gastric cancer cells, infected with a retroviral vector containing super-suppressive mutant form of IκBα (IκBαM), were used for animal studies as well as cell culture experiments. Xenografted tumours were measured and IκBαM effects on angiogenesis and HIF-1α activation were assessed by immunohistochemistry, western blotting, luciferase reporter assay, and semiquantitative reverse transcription-polymerase chain reaction. In addition, NF-κB effects on the HIF-1α degradation and synthesis were examined.

RESULTS

Hypoxia-inducible factor-1α activation positively correlated with RelA activation in clinical gastric cancer samples (P<0.001). The IκBαM overexpression suppressed tumour growth, microvessel density, and HIF-1α activation in xenografted tumours. Cell culture experiments showed that hypoxia-induced HIF-1α expression was reduced by NF-κB inhibition under hypoxic conditions at the translational level.

CONCLUSION

The hypoxia-dependent activation of the NF-κB/HIF-1α/VEGF pathway contributes, at least in part, to gastric cancer promotion via enhancement of angiogenesis.

Drosophila G9a is implicated in germ cell development

In Drosophila ovaries, germline stem cells (GSCs) divide asymmetrically in the germaria to produce daughter GSCs and cystoblasts. Single cystoblasts differentiate to form germline cysts with 16 germline cells, all of which are connected by the fusome, a vesiculated structure critical for oocyte specification. We here show that histone H3K9 methyltransferase dg9a is associated with spectrosome/fusome formation in the germarium; dG9a(13414) mutant ovaries have disorganized spectrosome/fusome in about half the germaria, with reduced levels of hu-li tai shao and alpha-SPECTRIN proteins. We found that the amount of germline cells within cysts was reduced and that oocyte determination often failed in egg chambers of the dG9a(13414) mutant ovaries. These results suggest that a mutation in dG9a gene gives rise to anomalous spectrosome/fusome structures, which in turn lead to faulty germ-cell development in Drosophila ovaries.

Distributed modelling of urban runoff using a meta-channel concept

Hydraulic flood routing is advantageous for computational accuracy; however, it requires individual calculations of an extensive pipe network in the case of a two-dimensional analysis. In this study, a method for considering the characteristics of a two-dimensional pipe network has been developed using the meta-channel concept to simplify the detailed calculations involved in the estimation of runoff from urban catchments. In essence, the meta-channel concept turns a two-dimensional pipe network into a one-dimensional pipe with an effective hydraulic geometry. Once such geometry has been identified, the flood routing can then be performed for an urban drainage system. A nonlinear diffusion wave equation, derived from the Saint-Venant equation, was used for flood routing, with an explicit method used for the numerical solution. The celerity and diffusion coefficients, which are two parameters of the diffusion wave equation, were estimated for the Goonja drainage from a two-dimensional pipe network using the meta-channel concept. A comparison of the results of the meta-channel-based pipe routing with the distributed SWMM simulation and observed data, showed close similarities, and identified the applicability of the meta-channel concept in an urban drainage setting.

Phase II study of irinotecan, 5-fluorouracil (5-FU) and leucovorin combination chemotherapy in taxane and cisplatin-based chemotherapy-refractory metastatic gastric cancer

e15599

Background: The role of the second line chemotherapy in advanced gastric cancer was not clear, but possibility of prolongation of survival is open question. Irinotecan is promising agents in gastric cancer and this phase II study evaluated the efficacy and safety of combination chemotherapy with irinotecan, high dose of 5-fluorouracil (5-FU) and leucovorin in taxane and cisplatin based chemotherapy refractory metastatic gastric cancer. Methods: Eligible criteria were as followed; histologic confirmed adenocarcinoma of stomach, previously treated with taxane and cisplatin, age≥18, Eastern Clinical Oncology Group (ECOG) performance status of 1 or less, adequate organ function. Irinotecan (150 mg/m2) as a 30-min infusion and leucovorin (200 mg/m2) as a 15-min infusion were given on day 1, followed by 5-FU 400 mg/m2bolus infusion then 5-FU 2,400 mg/m2 as a 48-hour continuous infusion. This cycle was repeated every 2 weeks until disease progression or unacceptable toxicities. Results: Thirty-four patients were enrolled. The median age was 57 years (range 27–73 years), and the ECOG performance status of all patients was 1. All patients were evaluable for safety and survival and twenty seven patients (79.4%) were evaluable for tumor response. The overall response rate was 18.5% (95% CI: 3.9–33.1). The median progression free survival and overall survival were 4.6 (95% CI: 2.4–6.9) and 9.3 months (95% CI: 5.2–13.4), respectively. Greater than grade 3 haematological toxicities were neutropenia in nine (26.5%), febrile neutropenia in one (2.9%) and thrombocytopenia in one patient (2.9%). The major non-haematological toxicity was asthenia, but most of patients showed grade 1 or 2. Greater than grade 3 non- haematological toxicities were elevated AST/ALT in four (11.8%), hyperbilirubinemia in two (5.9%), nausea in two patients (5.9%). Conclusions: This results showed that the combination chemotherapy with irinotecan, 5-FU and leucovorin was well tolerated and active in taxane and cisplatin refractory patients.

No significant financial relationships to disclose.