Search results for "Screening"
showing 10 items of 1150 documents
Vacuum correlators at short distances from lattice QCD
2021
Non-perturbatively computing the hadronic vacuum polarization at large photon virtualities and making contact with perturbation theory enables a precision determination of the electromagnetic coupling at the $Z$ pole, which enters global electroweak fits. In order to achieve this goal ab initio using lattice QCD, one faces the challenge that, at the short distances which dominate the observable, discretization errors are hard to control. Here we address challenges of this type with the help of static screening correlators in the high-temperature phase of QCD, yet without incurring any bias. The idea is motivated by the observations that (a) the cost of high-temperature simulations is typica…
On the strength of the U A (1) anomaly at the chiral phase transition in N f = 2 QCD
2016
We study the thermal transition of QCD with two degenerate light flavours by lattice simulations using $O(a)$-improved Wilson quarks. Temperature scans are performed at a fixed value of $N_t = (aT)^{-1}=16$, where $a$ is the lattice spacing and $T$ the temperature, at three fixed zero-temperature pion masses between 200 MeV and 540 MeV. In this range we find that the transition is consistent with a broad crossover. As a probe of the restoration of chiral symmetry, we study the static screening spectrum. We observe a degeneracy between the transverse isovector vector and axial-vector channels starting from the transition temperature. Particularly striking is the strong reduction of the split…
Calibration and Characterization of the IceCube Photomultiplier Tube
2010
Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resoluti…
First search for extremely high energy cosmogenic neutrinos with the IceCube Neutrino Observatory.
2010
We report on the results of the search for extremely-high energy (EHE) neutrinos with energies above $10^7$ GeV obtained with the partially ($\sim$30%) constructed IceCube in 2007. From the absence of signal events in the sample of 242.1 days of effective livetime, we derive a 90% C.L. model independent differential upper limit based on the number of signal events per energy decade at $E^2 \phi_{\nu_e+\nu_\mu+\nu_\tau}\simeq 1.4 \times 10^{-6}$ GeV cm$^{-2}$ sec$^{-1}$ sr$^{-1}$ for neutrinos in the energy range from $3\times10^7$ to $3\times10^9$ GeV.
Three-Body Coulomb Effects in the Direct Coulomb Breakup of 8B into 7Be + p in the Field of a 208Pb Ion
1999
The amplitude for the Coulomb breakup of a light nucleus in the field of a highly charged ion is considered in the framework of the distorted wave approach, with particular emphasis being laid on correctly taking into account the three-body Coulomb interactions in the final state. Numerical calculations have been performed for the double differential cross section for the reaction 208Pb(8B, 7Be p)208Pb. They clearly demonstrate the importance of long-range three-body Coulomb correlations in the astrophysically interesting regime when the ejectiles have the extremely small relative energies.
Saponins from the Roots of Nylandtia spinosa
2007
From the roots of Nylandtia spinosa, four new triterpene saponins, 3- O-beta- d-glucopyranosylpresenegenin 28- O-beta- d-galactopyranosyl-(1-->4)-[alpha- l-arabinopyranosyl-(1-->3)]-beta- d-xylopyranosyl-(1-->4)-[beta- d-apiofuranosyl-(1-->3)]-alpha- l-rhamnopyranosyl-(1-->2)-beta- d-fucopyranosyl ester ( 1), 3- O-beta- d-glucopyranosylpresenegenin 28- O-beta- d-galactopyranosyl-(1-->4)-[alpha- l-arabinopyranosyl-(1-->3)]-beta- d-xylopyranosyl-(1-->4)-alpha- l-rhamnopyranosyl-(1-->2)-beta- d-fucopyranosyl ester ( 2), 3- O-beta- d-glucopyranosylpresenegenin 28- O-beta- d-apiofuranosyl-(1-->4)-[beta- d-galactopyranosyl-(1-->2)]-beta- d-xylopyranosyl-(1-->4)-alpha- l-rhamnopyranosyl-(1-->2)-be…
Immunoanalytical methods for ochratoxin A monitoring in wine and must based on innovative immunoreagents.
2020
Immunochemical methods are highly deployed in analytical laboratories worldwide for monitoring the incidence of mycotoxins in the food chain. Nevertheless, most conventional immunoassays for ochratoxin A (OTA), including commercial kits, show limitations to robustly determine this mycotoxin in grape-derived products below regulated levels (2 ng/mL). Herein, two rapid tests for sensitive OTA determination in wine and must were developed capitalizing on a collection of bioconjugates from innovative synthetic haptens and monoclonal antibodies with subnanomolar affinity. The ELISA (LOD = 8 pg/mL) showed excellent performance in recovery studies, and it was applied to survey commercial wines and…
Knowledge and attitudes of general population belonging to pharmacies of the Province of Palermo regarding the colorectal carcinoma screening: Result…
2020
Colorectal cancer (CC) is one of the leading cause of deaths every year. Oncological screening are health and social intervention that aims to diagnose a disease in an early stage. Although the high sensitivity and specificity of the colorectal cancer screening (CCS), the adherence in the Southern Italian Administrative Regions is low. A cross-sectional study on a sample of subjects belonging to five pharmacies located in the Province of Palermo, Italy, was conducted between June 2019 and February 2020 in order to evaluate knowledge and attitudes of general population regarding CC and CCS. A higher knowledge score among population interviewed was significantly associated with residency in P…
Neoadjuvant therapy for breast cancer
2019
Objective: To evaluate the frequency of neoadjuvant therapy (NT) in women with stage I–III breast cancer in Italy and whether it is influenced by biological characteristics, screening history, and geographic area. Methods: Data from the High Resolution Study conducted in 7 Italian cancer registries were used; they are a representative sample of incident cancers in the study period (2009–2013). Included were 3546 women aged <85 years (groups <50, 50–69, 70–64, and 75+) with stage I–III breast cancer at diagnosis who underwent surgery. Women were classified as receiving NT if they received chemotherapy, target therapy, and/or hormone therapy before the first surgical treatment. Logistic…
Comparison of prostate cancer survival in Germany and the USA: can differences be attributed to differences in stage distributions?
2016
Objectives To better understand the influence of prostate-specific antigen (PSA) screening and other health system determinants on prognosis of prostate cancer, up-to-date relative survival (RS), stage distributions, and trends in survival and incidence in Germany were evaluated and compared with the United States of America (USA). Patients and methods Incidence and mortality rates for Germany and the USA for the period 1999-2010 were obtained from the Centre for Cancer Registry Data at the Robert Koch Institute and the USA Surveillance Epidemiology and End Results (SEER) database. For analyses on stage and survival, data from 12 population-based cancer registries in Germany and from the SE…