10,485 research outputs found
Thoracoabdominal aneurysm surgery. Update on "open" versus "hybrid" treatment and personal experience
Thoracoabdominal aneurysm surgery. Update on "open" versus "hybrid" treatment and personal experience
TLEP, first step in a long-term vision for HEP
The discovery of H(126) has renewed interest in circular e+e- colliders that
can operate as Higgs factories, which benefit from three unique
characteristics: i) high luminosity and reliability, ii) the availability of
several interaction points, iii) superior beam energy accuracy. TLEP is an e+e-
storage ring of 80-km circumference that can operate with very high luminosity
from the Z peak (90 GeV) to the top quark pair threshold (350 GeV). It can
achieve transverse beam polarization at the Z peak and WW threshold, giving it
unparalleled accuracy on the beam energy. A preliminary study indicates that an
80 km tunnel could be constructed around CERN. Such a tunnel would allow a 100
TeV proton-proton collider to be established in the same ring (VHE-LHC),
offering a long term vision.Comment: This is a contribution to the the Snowmass process 2013: Frontier
Capabilitie
A QCD sum rule calculation of the decay width
To understand the nature of the , recently observed in the mass
spectrum of the system by the D0 Collaboration, we have
investigated, in a previous work, a scalar tetraquark (diquak-antidiquark)
structure for it, within the two-point QCD sum rules method. The result found
for its mass agrees well with the experimental value. Encouraged by this
finding we now extend our calculations to obtain the decay width of
to using the three-point QCD sum rule. We obtain a value of
(20.4\pm8.7)\MeV, which, on comparing with the experimental value of
21.9\pm6.4 (\mbox{sta})^{+5.0}_{-2.5}(\mbox{syst}) \MeV/c^2, reinforces the
scalar four quark nature of .Comment: Minor modifications made. Some new discussions and references adde
Comments on "Wall-plug (AC) power consumption of a very high energy e+/e- storage ring collider" by Marc Ross
The paper arXiv:1308.0735 questions some of the technical assumptions made by
the TLEP Steering Group when estimating in arXiv:1305.6498 the power
requirement for the very high energy e+e- storage ring collider TLEP. We show
that our assumptions are based solidly on CERN experience with LEP and the LHC,
as well accelerators elsewhere, and confirm our earlier baseline estimate of
the TLEP power consumption.Comment: 6 page
Una via per tornare allo sviluppo: rendersi indispensabili nella rete
L’articolo esamina le potenzialità di crescita dell’industria italiana, al fine di individuare una miglior destinazione delle risorse disponibili per la ricerca.
Il contributo ruota attorno a due temi centrali: in primo luogo, nell’attuale scenario economico internazionale, la produzione di beni e servizi di maggior valore è prioritaria rispetto alla necessità di abbattimento dei costi di produzione; in secondo luogo, considerato il crescente ruolo delle catene di fornitura nella produzione dei beni di contenuto tecnologicamente avanzato, lo sviluppo economico di un determinato territorio richiede la specializzazione in alcuni dei nodi della rete di fornitura più che non la presenza in tutte le sue fasi. Ne discende l’obiettivo di rendersi indispensabili in quegli anelli del processo di produzione che manifestano rilevanti prospettive di crescita.
Il concetto di indispensabilità, con le sue ripercussioni sul benessere, viene analizzato mediante appositi modelli teorici. Vengono poi predisposti indicatori economico-statistici in grado di cogliere l’idea di indispensabilità, e di misurarne il livello per vari settori dell’economia italiana. Sulla base dei risultati dell’analisi, si derivano le implicazioni di policy in relazione all’allocazione dei contributi pubblici alla ricerc
Blood samples drawn for culture as a surrogate marker for case-mix adjustment of hospital antibiotic use.
Hospital antibiotic consumption is generally adjusted to occupancy. This study hypothesised that the number of blood culture samples could be a surrogate marker for case-mix adjustment. Antibiotic consumption was compared over 16 consecutive trimesters in one medical ward in terms of patient-days or blood culture samples. Compared with patient-days, measurement adjusted to blood culture samples detected three trimesters with an unusually high consumption, and one trimester with consumption falsely classified as high because of a high incidence of infections. Blood culture numbers enabled easy and accurate identification of periods with a drift in antibiotic consumption ina medical ward
A parallel Block Lanczos algorithm and its implementation for the evaluation of some eigenvalues of large sparse symmetric matrices on multicomputers
In the present work we describe HPEC (High Performance Eigenvalues Computation), a parallel software package for the
evaluation of some eigenvalues of a large sparse symmetric matrix. It implements an efficient and portable Block Lanczos
algorithm for distributed memory multicomputers. HPEC is based on basic linear algebra operations for sparse and dense
matrices, some of which have been derived by ScaLAPACK library modules. Numerical experiments have been carried out
to evaluate HPEC performance on a cluster of workstations with test matrices from Matrix Market and Higham’s collections.
A comparison with a PARPACKroutine is also detailed. Finally, parallel performance is evaluated on random matrices, using
standard parameters
Molecular Epidemiology of Pseudomonas aeruginosa in the Intensive Care Units – A Review
Pseudomonas aeruginosa is one of the leading nosocomial pathogens in intensive care units (ICU). This opportunist pathogen is commonly recovered from moist environments, and is also found colonizing 2.6 to 24% of hospitalized patients. We reviewed the recent literature that used highly discriminatory typing methods to precisely identify the reservoirs and modes of transmission of this microorganism in the ICU setting. In most ICUs, the endogenous flora was suspected to be the main source of infection compared to exogenous sources (other patients, the contaminated environment such as sinks or taps). However, the percentage of endogenous versus exogenous sources might vary considerably from one setting to another. Reasons for this include the compliance of health care workers to infection control measures, the contamination of the environment, and probably also the biology of the pathogen (intrinsic fitness factors). As P. aerugi-nosa is ubiquitous in the environment and colonizes up to 15% of hospitalized patients, eradication of the reservoir is difficult, if not impossible. Therefore, efforts should primarily focus on reinforcement of infection control measures to limit its transmission
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