4,821 research outputs found
Cutaneous clinico-pathological findings in three covid-19-positive patients observed in the metropolitan area of Milan, Italy
Production of Scalar Higgs Bosons Associated with Boson at the CERN LHC in the MSSM
We investigate the associated production of a scalar Higgs boson ( or
) with boson in the minimal supersymmetric extension of the standard
model (MSSM) at the CERN Large Hadron Collider (LHC), including the
contributions from annihilation at the tree level and gluon fusion
via quark and squark loops. We quantitatively analyze the total cross sections
in the mSUGRA scenario. For the production of associated with , we
find that in most of the parameter regions, the contributions from initial
and are at a level of one percent of the total cross section
and therefore almost insignificant. For the production of associated with
, the contributions from channel can be much larger than those
from light quark initial states. Especially for large , the
increment can reach about one order of magnitude. Thus, when considering the
associated production of and at the LHC, the contributions from
annihilation should be taken into account seriously.Comment: 19 pages, 8 figures, RevTeX4; one reference added, minor changes,
conclusion unchanged; Journal-ref adde
Virological rebound in human immunodeficiency virus-infected patients with or without residual viraemia: results from an extended follow-up
AbstractHuman immunodeficiency virus (HIV) -infected patients with HIV RNA loads of < 50 copies/mL were followed-up for a median (interquartile range) of 30.8 (11.7–32.9) months to study the effect of residual viraemia (RV) on virological rebound (VR). At baseline, 446 (60.3%) patients had undetectable HIV RNA (group A) and 293 (39.7%) had RV (1–49 HIV RNA copies/mL, group B) by kinetic PCR. VR occurred in 4 (0.9%) patients in group A and in 12 (4.1%) patients in group B (p 0.007). Time to VR was shorter among patients of group B (Log-rank test: p 0.003). However, the proportion of VR was extremely low also among patients with RV
The super-LHC
We review here the prospects of a long-term upgrade programme for the Large
Hadron Collider (LHC), CERN laboratory's new proton-proton collider. The
super-LHC, which is currently under evaluation and design, is expected to
deliver of the order of ten times the statistics of the LHC. In addition to a
non-technical summary of the principal physics arguments for the upgrade, I
present a pedagogical introduction to the technological challenges on the
accelerator and experimental fronts, and a review of the current status of the
planning.Comment: To appear in Contemporary Physic
Crystal slow extraction of positrons from DAΦNE: the SHERPA project
The SHERPA project aim is to develop an efficient technique to extract a positron beam from one of the accelerator rings composing the DAΦNE complex at the Frascati National Laboratory of INFN, setting up a new beam line able to deliver positron spills of O(ms) length, excellent beam energy spread and emittance. The most common approach to slowly extract from a ring is to increase betatron oscillations approaching a tune resonance in order to gradually eject particles from the circulating beam. SHERPA proposes a paradigm change using coherent processes in bent crystals to kick out positrons from the ring, a cheaper and less complex alternative. A description of this innovative nonresonant extraction technique is reported in this manuscript, including its performance preliminary estimation
Cutaneous manifestations of COVID-19: Report of three cases and a review of literature
Background: Various cutaneous manifestations have been observed in patients with COVID-19 infection. However, overall similarities in the clinical presentation of these dermatological manifestations have not yet been summarized. Objective: This review aims to provide an overview of various cutaneous manifestations in patients with COVID-19 through three case reports and a literature review. Methods: A literature search was conducted using PubMed, OVID, and Google search engines for original and review articles. Studies written in the English language that mentioned cutaneous symptoms and COVID-19 were included. Results: Eighteen articles and three additional cases reported in this paper were included in this review. Of these studies, 6 are case series and 12 are case report studies. The most common cutaneous manifestation of COVID-19 was found to be maculopapular exanthem (morbilliform), presenting in 36.1% (26/72) patients. The other cutaneous manifestations included: a papulovesicular rash (34.7%, 25/72), urticaria (9.7%, 7/72), painful acral red purple papules (15.3%, 11/72) of patients, livedo reticularis lesions (2.8%, 2/72) and petechiae (1.4%, 1/72). Majority of lesions were localized on the trunk (66.7%, 50/72), however, 19.4% (14/72) of patients experienced cutaneous manifestations in the hands and feet. Skin lesion development occurred before the onset of respiratory symptoms or COVID-19 diagnosis in 12.5% (9/72) of the patients, and lesions spontaneously healed in all patients within 10 days. Majority of the studies reported no correlation between COVID-19 severity and skin lesions. Conclusion: Infection with COVID-19 may result in dermatological manifestations with various clinical presentations, which may aid in the timely diagnosis of this infection
The Straw Tube Trackers of the PANDA Experiment
The PANDA experiment will be built at the FAIR facility at Darmstadt
(Germany) to perform accurate tests of the strong interaction through bar pp
and bar pA annihilation's studies. To track charged particles, two systems
consisting of a set of planar, closed-packed, self-supporting straw tube layers
are under construction. The PANDA straw tubes will have also unique
characteristics in term of material budget and performance. They consist of
very thin mylar-aluminized cathodes which are made self-supporting by means of
the operation gas-mixture over-pressure. This solution allows to reduce at
maximum the weight of the mechanical support frame and hence the detector
material budget. The PANDA straw tube central tracker will not only reconstruct
charged particle trajectories, but also will help in low momentum (< 1 GeV)
particle identification via dE/dx measurements. This is a quite new approach
that PANDA tracking group has first tested with detailed Monte Carlo
simulations, and then with experimental tests of detector prototypes. This
paper addresses the design issues of the PANDA straw tube trackers and the
performance obtained in prototype tests.Comment: 7 pages,16 figure
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