336 research outputs found
Search for Standard Model Higgs Boson Production in Association with a W Boson using a Neural Network
We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector that correspond to an integrated luminosity of approximately 1.9 inverse fb. We select events consistent with a signature of a single charged lepton, missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method, a jet probability tagging method, and a neural network filter. We use kinematic information in an artificial neural network to improve discrimination between signal and background compared to previous analyses. The observed number of events and the neural network output distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching fraction ranging from 1.2 to 1.1 pb or 7.5 to 102 times the standard model expectation for Higgs boson masses from 110 to $150 GeV/c^2, respectively.We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (pp̅ →W±H→ℓνbb̅ ) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector that correspond to an integrated luminosity of approximately 1.9 fb-1. We select events consistent with a signature of a single charged lepton (e±/μ±), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method, a jet probability tagging method, and a neural network filter. We use kinematic information in an artificial neural network to improve discrimination between signal and background compared to previous analyses. The observed number of events and the neural network output distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching fraction ranging from 1.2 to 1.1 pb or 7.5 to 102 times the standard model expectation for Higgs boson masses from 110 to 150 GeV/c2, respectively.Peer reviewe
Triple-Tube-Ostomy: A Novel Technique for the Surgical Treatment of Iatrogenic Duodenal Perforation
Although duodenal perforation is currently an infrequent complication of medical procedures, its incidence in the future predictably will increase as endoscopic treatment of duodenal neoplasms becomes more frequently used. In some cases, duodenal perforation is difficult to treat even surgically. We report here a novel technique called ‘triple-tube-ostomy’ for the treatment of iatrogenic duodenal perforation. Since November 2009, there have been three cases of iatrogenic perforation of the duodenum, due to various causes, which we have treated with our novel technique. The main principles of the technique are biliary diversion, decompression of the duodenum, and early enteral nutrition. All patients who underwent the triple-tube-ostomy procedure had good postoperative courses, with few complications. The novel surgical technique we describe in this report is safe, reliable, easy to learn and perform, and led to a good postoperative course in all cases where we performed it
Tissue microarray analysis of eIF4E and its downstream effector proteins in human breast cancer
Correction to Kleiner HE, Krishnan P, Tubbs J, Smith M, Meschonat C, Shi R, Lowery-Nordberg M, Adegboyega P, Unger M, Cardelli J et al: Tissue microarray analysis of eIF4E and its downstream effector proteins in human breast cancer. J Exp Clin Cancer Res 2009, 28:5
Do Herbivores Eavesdrop on Ant Chemical Communication to Avoid Predation?
Strong effects of predator chemical cues on prey are common in aquatic and marine ecosystems, but are thought to be rare in terrestrial systems and specifically for arthropods. For ants, herbivores are hypothesized to eavesdrop on ant chemical communication and thereby avoid predation or confrontation. Here I tested the effect of ant chemical cues on herbivore choice and herbivory. Using Margaridisa sp. flea beetles and leaves from the host tree (Conostegia xalapensis), I performed paired-leaf choice feeding experiments. Coating leaves with crushed ant liquids (Azteca instabilis), exposing leaves to ant patrolling prior to choice tests (A. instabilis and Camponotus textor) and comparing leaves from trees with and without A. instabilis nests resulted in more herbivores and herbivory on control (no ant-treatment) relative to ant-treatment leaves. In contrast to A. instabilis and C. textor, leaves previously patrolled by Solenopsis geminata had no difference in beetle number and damage compared to control leaves. Altering the time A. instabilis patrolled treatment leaves prior to choice tests (0-, 5-, 30-, 90-, 180-min.) revealed treatment effects were only statistically significant after 90- and 180-min. of prior leaf exposure. This study suggests, for two ecologically important and taxonomically diverse genera (Azteca and Camponotus), ant chemical cues have important effects on herbivores and that these effects may be widespread across the ant family. It suggests that the effect of chemical cues on herbivores may only appear after substantial previous ant activity has occurred on plant tissues. Furthermore, it supports the hypothesis that herbivores use ant chemical communication to avoid predation or confrontation with ants
Tumor Associated Stromal Cells Play a Critical Role on the Outcome of the Oncolytic Efficacy of Conditionally Replicative Adenoviruses
The clinical efficacy of conditionally replicative oncolytic adenoviruses (CRAd) is still limited by the inefficient infection of the tumor mass. Since tumor growth is essentially the result of a continuous cross-talk between malignant and tumor-associated stromal cells, targeting both cell compartments may profoundly influence viral efficacy. Therefore, we developed SPARC promoter-based CRAds since the SPARC gene is expressed both in malignant cells and in tumor-associated stromal cells. These CRAds, expressing or not the Herpes Simplex thymidine kinase gene (Ad-F512 and Ad(I)-F512-TK, respectively) exerted a lytic effect on a panel of human melanoma cells expressing SPARC; but they were completely attenuated in normal cells of different origins, including fresh melanocytes, regardless of whether cells expressed or not SPARC. Interestingly, both CRAds displayed cytotoxic activity on SPARC positive-transformed human microendothelial HMEC-1 cells and WI-38 fetal fibroblasts. Both CRAds were therapeutically effective on SPARC positive-human melanoma tumors growing in nude mice but exhibited restricted efficacy in the presence of co-administered HMEC-1 or WI-38 cells. Conversely, co-administration of HMEC-1 cells enhanced the oncolytic efficacy of Ad(I)-F512-TK on SPARC-negative MIA PaCa-2 pancreatic cancer cells in vivo. Moreover, conditioned media produced by stromal cells pre-infected with the CRAds enhanced the in vitro viral oncolytic activity on pancreatic cancer cells, but not on melanoma cells. The whole data indicate that stromal cells might play an important role on the outcome of the oncolytic efficacy of conditionally replicative adenoviruses.Facultad de Ciencias Veterinaria
Plasma phosphorylated-tau181 as a predictive biomarker for Alzheimer’s amyloid, tau and FDG PET status
Plasma phosphorylated-tau181 (p-tau181) showed the potential for Alzheimer’s diagnosis and prognosis, but its role in detecting cerebral pathologies is unclear. We aimed to evaluate whether it could serve as a marker for Alzheimer’s pathology in the brain. A total of 1189 participants with plasma p-tau181 and PET data of amyloid, tau or FDG PET were included from ADNI. Cross-sectional relationships of plasma p-tau181 with PET biomarkers were tested. Longitudinally, we further investigated whether different p-tau181 levels at baseline predicted different progression of Alzheimer’s pathological changes in the brain. We found plasma p-tau181 significantly correlated with brain amyloid (Spearman ρ = 0.45, P 18.85 pg/ml) at baseline had a higher risk of pathological progression in brain amyloid (HR: 2.32, 95%CI 1.32–4.08) and FDG PET (3.21, 95%CI 2.06–5.01) status. Plasma p-tau181 may be a sensitive screening test for detecting brain pathologies, and serve as a predictive biomarker for Alzheimer’s pathophysiology
Time-Resolved FRET -Based Approach for Antibody Detection - A New Serodiagnostic Concept
Peer reviewe
Production of dust by massive stars at high redshift
The large amounts of dust detected in sub-millimeter galaxies and quasars at
high redshift pose a challenge to galaxy formation models and theories of
cosmic dust formation. At z > 6 only stars of relatively high mass (> 3 Msun)
are sufficiently short-lived to be potential stellar sources of dust. This
review is devoted to identifying and quantifying the most important stellar
channels of rapid dust formation. We ascertain the dust production efficiency
of stars in the mass range 3-40 Msun using both observed and theoretical dust
yields of evolved massive stars and supernovae (SNe) and provide analytical
expressions for the dust production efficiencies in various scenarios. We also
address the strong sensitivity of the total dust productivity to the initial
mass function. From simple considerations, we find that, in the early Universe,
high-mass (> 3 Msun) asymptotic giant branch stars can only be dominant dust
producers if SNe generate <~ 3 x 10^-3 Msun of dust whereas SNe prevail if they
are more efficient. We address the challenges in inferring dust masses and
star-formation rates from observations of high-redshift galaxies. We conclude
that significant SN dust production at high redshift is likely required to
reproduce current dust mass estimates, possibly coupled with rapid dust grain
growth in the interstellar medium.Comment: 72 pages, 9 figures, 5 tables; to be published in The Astronomy and
Astrophysics Revie
First measurement of the |t|-dependence of coherent J/ψ photonuclear production
The first measurement of the cross section for coherent J/ψ photoproduction as a function of |t|, the square of the momentum transferred between the incoming and outgoing target nucleus, is presented. The data were measured with the ALICE detector in ultra-peripheral Pb–Pb collisions at a centre-of-mass energy per nucleon pair sNN=5.02TeV with the J/ψ produced in the central rapidity region |y|<0.8, which corresponds to the small Bjorken-x range (0.3−1.4)×10−3.
The measured |t|-dependence is not described by computations based only on the Pb nuclear form factor, while the photonuclear cross section is better reproduced by models including shadowing according to the leading-twist approximation, or gluon-saturation effects from the impact-parameter dependent Balitsky–Kovchegov equation. These new results are therefore a valid tool to constrain the relevant model parameters and to investigate the transverse gluonic structure at very low Bjorken-x.publishedVersio
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