28 research outputs found
On direct measurement of the W production charge asymmetry at the LHC
The prospects for making a direct measurement of the W production charge
asymmetry at the LHC are discussed. A modification to the method used at the
Tevatron is proposed for measurements at the LHC. The expected sensitivity for
such a measurement to parton distribution functions is compared to that for a
measurement of the lepton charge asymmetry. The direct measurement approach is
found to be less useful for placing constraints on parton distribution
functions at the LHC than a measurement of the lepton charge asymmetry.Comment: 18 pages, 10 figures, v2: references and keywords updated v3:
Additional paragraph discussing inclusion of W asymmetry in global fits adde
Low Q^2 Jet Production at HERA and Virtual Photon Structure
The transition between photoproduction and deep-inelastic scattering is
investigated in jet production at the HERA ep collider, using data collected by
the H1 experiment. Measurements of the differential inclusive jet
cross-sections dsigep/dEt* and dsigmep/deta*, where Et* and eta* are the
transverse energy and the pseudorapidity of the jets in the virtual
photon-proton centre of mass frame, are presented for 0 < Q2 < 49 GeV2 and 0.3
< y < 0.6. The interpretation of the results in terms of the structure of the
virtual photon is discussed. The data are best described by QCD calculations
which include a partonic structure of the virtual photon that evolves with Q2.Comment: 20 pages, 5 Figure
Hadron Production in Diffractive Deep-Inelastic Scattering
Characteristics of hadron production in diffractive deep-inelastic
positron-proton scattering are studied using data collected in 1994 by the H1
experiment at HERA. The following distributions are measured in the
centre-of-mass frame of the photon dissociation system: the hadronic energy
flow, the Feynman-x (x_F) variable for charged particles, the squared
transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a
function of x_F. These distributions are compared with results in the gamma^* p
centre-of-mass frame from inclusive deep-inelastic scattering in the
fixed-target experiment EMC, and also with the predictions of several Monte
Carlo calculations. The data are consistent with a picture in which the
partonic structure of the diffractive exchange is dominated at low Q^2 by hard
gluons.Comment: 16 pages, 6 figures, submitted to Phys. Lett.
Measurement of D* Meson Cross Sections at HERA and Determination of the Gluon Density in the Proton using NLO QCD
With the H1 detector at the ep collider HERA, D* meson production cross
sections have been measured in deep inelastic scattering with four-momentum
transfers Q^2>2 GeV2 and in photoproduction at energies around W(gamma p)~ 88
GeV and 194 GeV. Next-to-Leading Order QCD calculations are found to describe
the differential cross sections within theoretical and experimental
uncertainties. Using these calculations, the NLO gluon momentum distribution in
the proton, x_g g(x_g), has been extracted in the momentum fraction range
7.5x10^{-4}< x_g <4x10^{-2} at average scales mu^2 =25 to 50 GeV2. The gluon
momentum fraction x_g has been obtained from the measured kinematics of the
scattered electron and the D* meson in the final state. The results compare
well with the gluon distribution obtained from the analysis of scaling
violations of the proton structure function F_2.Comment: 27 pages, 9 figures, 2 tables, submitted to Nucl. Phys.
A Purity Monitoring System for the H1 Liquid Argon Calorimeter
The ionization probes used for monitoring the liquid argon purity in the H1
calorimeter are described and results of their operation in tests at CERN and
during the period 1992 to the end of 1998 at HERA are given. The high
sensitivity of the charge measurements leads to refined charge collection
models, and to the observation of a variation of the ionization yield of our
electron sources with temperature.Comment: 26 pages, 14 figure
Psoas muscle mass, nutritional status, inflammation, and their relationship with prognosis in patients with pancreatic adenocarcinoma
Introduction: some factors have been shown to be associated with survival in patients with pancreatic adenocarcinoma. Recently, some studies suggested that malnutrition, muscle mass, and inflammation might have an effect on survival in patients with pancreatic malignancy. Objectives: to investigate the association between psoas muscle mass, inflammation, nutritional status at the time of diagnosis, and survival in patients with pancreatic adenocarcinoma. Methods: this retrospective study included 219 patients diagnosed with pancreatic carcinoma. The nutritional status, inflammation, and psoas muscle mass of the patients at the time of diagnosis were evaluated. Nutritional status was assessed using the Prognostic Nutritional Index (PNI). Leucocyte count and neutrophil/lymphocyte ratio (NLR) were used for inflammation assessment. Psoas muscle mass was calculated by using abdominal computed tomography images of the patients. Results: the mean age of patients (80 female and 139 male) was 66.6 ± 11.7 years. According to the PNI results, 155 patients had a normal nutritional status (70 %), whereas 64 patients were malnourished (30 %). The survival of the patients with normal nutritional status was significantly longer than that of those who were malnourished (p < 0.001). There was no significant relationship between psoas muscle area, leucocyte count, NLR, and survival time. Conclusion: the survival of pancreatic adenocarcinoma patients with malnutrition at the time of diagnosis was significantly shorter than for patients without malnutrition. © 2021 SENPE y©Arán Ediciones S.L.2-s2.0-85118131525PubMed: 3422376
Relationship between chromosomal aberrations and gene expressions in the p53 pathway in chronic lymphocytic leukemia
Chronic lymphocytic leukemia (CLL) is a neoplasm characterized by excessive accumulation of B lymphocytes in the peripheral blood, bone marrow and lymph nodes. We assessed the expressions of 22 genes in the p53 pathway in 30 CLL patients and 15 healthy subjects by a RT2 Profiler PCR (polymerase chain reaction) Array technique and their relation to cytogenetic aberrations detected by fluorescent in situ hybridization (FISH). Our Student’s t-test results indicated that ATM, ATR, BAX, CASP9, CDK4, CDKN2A, CHEK1, CHEK2, E2F3, MCL1, MDM2, MDM4, PCNA, RB1, P53 and BCL2 genes were statistically significant (p <0.001). For six genes (APAF1, CDKN1A, E2F1, GADD45A, PTEN and PTX3) were not statistically significant. The ATM, ATR, BAX, CASP9, CDK4, CDKN1A, CDKN2A, CHEK1, CHEK2, MDM2, MDM4, PCNA, RB1, P53, E2F1, GADD45A and BCL2 genes were found to be upregulated by the 2-ᐃᐃCt (relative fold change in gene expression) method. The highest up-regulation was detected in CDKN2A and BCL2 genes, 10.22- and 8.51-fold, respectively. On the other hand, the PTX3 gene with a fold regulation of 1.84 was found to the highest downregulation. Overall, the CDNK2A BCL2 and PTX3 genes are related to the mechanism of the disease in the p53 pathway and may be an important predictor of the prognosis of the disease. The BCL2 gene may be associated with increased risk of developing CLL. We suggest that the PTX3 gene may be considered as a marker associated with CLL disease. The CDKN2A gene expression seems to play a protective role in CLL
Relation between sarcopenia and dose-limiting toxicity in patients with metastatic colorectal cancer who received regorafenib
PMID = 3086838