1,260 research outputs found
Fermion Virtual Effects in Cross Section
We analyse the contribution of new heavy virtual fermions to the cross section. We find that there exists a relevant
interplay between trilinear and bilinear oblique corrections. The result
strongly depends on the chiral or vector--like nature of the new fermions. As
for the chiral case we consider sequential fermions: one obtains substantial
deviation from the Standard model prediction, making the effect possibly
detectable at or GeV linear colliders. As an example for
the vector--like case we take a SUSY extension with heavy charginos and
neutralinos: due to cancellation, the final effect turns out to be negligible.Comment: uuencoded, gz-compressed, tar-ed file. 8 pages, 4 EPS figures, uses
EPSFIG.ST
Testosterone insulin-like effects: an in vitro study on the short-term metabolic effects of testosterone in human skeletal muscle cells
Testosterone by promoting different metabolic pathways contributes to short-term homeostasis of skeletal muscle, the largest insulin-sensitive tissue and the primary site for insulin-stimulated glucose utilization. Despite evidences indicate a close relationship between testosterone and glucose metabolism, the molecular mechanisms responsible for a possible testosterone-mediated insulin-like effects on skeletal muscle are still unknown
Noncommutative Electrodynamics
In this paper we define a causal Lorentz covariant noncommutative (NC)
classical Electrodynamics. We obtain an explicit realization of the NC theory
by solving perturbatively the Seiberg-Witten map. The action is polynomial in
the field strenght , allowing to preserve both causality and Lorentz
covariance. The general structure of the Lagrangian is studied, to all orders
in the perturbative expansion in the NC parameter . We show that
monochromatic plane waves are solutions of the equations of motion to all
orders. An iterative method has been developed to solve the equations of motion
and has been applied to the study of the corrections to the superposition law
and to the Coulomb law.Comment: 13 pages, 2 figures, one reference adde
Many-core applications to online track reconstruction in HEP experiments
Interest in parallel architectures applied to real time selections is growing
in High Energy Physics (HEP) experiments. In this paper we describe performance
measurements of Graphic Processing Units (GPUs) and Intel Many Integrated Core
architecture (MIC) when applied to a typical HEP online task: the selection of
events based on the trajectories of charged particles. We use as benchmark a
scaled-up version of the algorithm used at CDF experiment at Tevatron for
online track reconstruction - the SVT algorithm - as a realistic test-case for
low-latency trigger systems using new computing architectures for LHC
experiment. We examine the complexity/performance trade-off in porting existing
serial algorithms to many-core devices. Measurements of both data processing
and data transfer latency are shown, considering different I/O strategies
to/from the parallel devices.Comment: Proceedings for the 20th International Conference on Computing in
High Energy and Nuclear Physics (CHEP); missing acks adde
NaNet: a Low-Latency, Real-Time, Multi-Standard Network Interface Card with GPUDirect Features
While the GPGPU paradigm is widely recognized as an effective approach to
high performance computing, its adoption in low-latency, real-time systems is
still in its early stages.
Although GPUs typically show deterministic behaviour in terms of latency in
executing computational kernels as soon as data is available in their internal
memories, assessment of real-time features of a standard GPGPU system needs
careful characterization of all subsystems along data stream path.
The networking subsystem results in being the most critical one in terms of
absolute value and fluctuations of its response latency.
Our envisioned solution to this issue is NaNet, a FPGA-based PCIe Network
Interface Card (NIC) design featuring a configurable and extensible set of
network channels with direct access through GPUDirect to NVIDIA Fermi/Kepler
GPU memories.
NaNet design currently supports both standard - GbE (1000BASE-T) and 10GbE
(10Base-R) - and custom - 34~Gbps APElink and 2.5~Gbps deterministic latency
KM3link - channels, but its modularity allows for a straightforward inclusion
of other link technologies.
To avoid host OS intervention on data stream and remove a possible source of
jitter, the design includes a network/transport layer offload module with
cycle-accurate, upper-bound latency, supporting UDP, KM3link Time Division
Multiplexing and APElink protocols.
After NaNet architecture description and its latency/bandwidth
characterization for all supported links, two real world use cases will be
presented: the GPU-based low level trigger for the RICH detector in the NA62
experiment at CERN and the on-/off-shore data link for KM3 underwater neutrino
telescope
Efficacy of SSRIs on cognition of Alzheimer's disease patients treated with cholinesterase inhibitors.
Background: This study examines the joint effect on cognition of selective serotonin re-uptake inhibitors
(SSRIs) and cholinesterase inhibitors (AChEIs) in depressed patients affected by Alzheimer’s disease (AD)
living at home.
Methods: The study was conducted in two different outpatient neurological clinics. 338 patients with probable
ADwere treated with ChEis (donepezil, rivastigmine and galantamine) as per the clinician’s judgment and were
observed for nine months. At study entry, participants underwent a multidimensional assessment evaluating
cognitive, functional and psychobehavioral domains. All patients were evaluated at baseline, after one (T1),
three (T2) and nine months (T3). Patients were grouped in three different categories (patients not depressed
and not treated with SSRIs, patients depressed and treated with SSRIs, and patients depressed but not treated
with SSRIs).
Results: At baseline 182 were diagnosed as not depressed and not treated with SSRIs, 66 as depressed and
treated with SSRIs, and 90 as depressed but not treated with SSRIs. The mean change in MMSE score
from baseline to nine months showed that depressed patients not treated worsened in comparison with those
not depressed and not treated with SSRIs (mean change −0.8±2.3 vs 0.04±2.9; p = 0.02) and patients
depressed and treated with SSRI (mean change −0.8±2.3 vs 0.1±2.5; p = 0.03).
Conclusions: In AD patients treated with AChEIs, SSRIs may exert some degree of protection against the
negative effects of depression on cognition
High-speed data transfer with FPGAs and QSFP+ modules
We present test results and characterization of a data transmission system
based on a last generation FPGA and a commercial QSFP+ (Quad Small Form
Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver
available in copper or optical cable assemblies for an aggregated bandwidth of
up to 40 Gbps. We implemented a complete testbench based on a commercial
development card mounting an Altera Stratix IV FPGA with 24 serial transceivers
at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We
present test results and signal integrity measurements up to an aggregated
bandwidth of 12 Gbps.Comment: 5 pages, 3 figures, Published on JINST Journal of Instrumentation
proceedings of Topical Workshop on Electronics for Particle Physics 2010,
20-24 September 2010, Aachen, Germany(R Ammendola et al 2010 JINST 5 C12019
Description of the relationship between NOHL classification in drug-induced sleep endoscopy and initial AHI in patients with moderate to severe OSAS, and evaluation of the results obtained with oral appliance therapy
Descrizione della relazione tra Classificazione NOHL definita durante la Drug-Induced Sleep Endoscopy e AHI iniziale in pazienti con OSAS da moderato a grave, e valutazione dei risultati ottenuti con dispositivi orali
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