University of Siena

About: University of Siena is a education organization based out in Siena, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 12179 authors who have published 33334 publications receiving 1008287 citations. The organization is also known as: Università degli studi di Siena & Universita degli studi di Siena.

A guide to LIGO–Virgo detector noise and extraction of transient gravitational-wave signals

Abstract: The LIGO Scientific Collaboration and the Virgo Collaboration have cataloged eleven confidently detected gravitational-wave events during the first two observing runs of the advanced detector era. All eleven events were consistent with being from well-modeled mergers between compact stellar-mass objects: black holes or neutron stars. The data around the time of each of these events have been made publicly available through the gravitational-wave open science center. The entirety of the gravitational-wave strain data from the first and second observing runs have also now been made publicly available. There is considerable interest among the broad scientific community in understanding the data and methods used in the analyses. In this paper, we provide an overview of the detector noise properties and the data analysis techniques used to detect gravitational-wave signals and infer the source properties. We describe some of the checks that are performed to validate the analyses and results from the observations of gravitational-wave events. We also address concerns that have been raised about various properties of LIGO–Virgo detector noise and the correctness of our analyses as applied to the resulting data.

Measurement of the lepton charge asymmetry in inclusive W production in pp collisions at √s=7 TeV

Abstract: A measurement of the lepton charge asymmetry in inclusive pp to WX production at sqrt(s)= 7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. This high precision measurement of the lepton charge asymmetry, performed in both the W to e nu and W to mu nu channels, provides new insights into parton distribution functions.

On the role of hand synergies in the optimal choice of grasping forces

Abstract: Recent work on the analysis of natural and robotic hands has introduced the notion of postural synergies as a principled organization of their complexity, based on the physical characteristics of the hand itself. Such characteristics include the mechanical arrangements of joints and fingers, their couplings, and the low-level control reflexes, that determine the specific way the concept of "hand" is embodied in a human being or a robot. While the focus of work done so far with postural synergies has been on motion planning for grasp acquisition, in this paper we set out to investigate the role that different embodiments have on the choice of grasping forces, and on the ultimate quality of the grasp. Numerical results are presented showing quantitatively the role played by different synergies (from the most fundamental to those of higher-order) in making a number of different grasps possible. The effect of number and types of engaged synergies on the distribution of optimal grasp forces is considered. Moreover, robustness of results is investigated with respect to variation in uncertain parameters such as contact and joint stiffness.

Diagnostic utility of ultrasonography versus nerve conduction studies in mild carpal tunnel syndrome

Abstract: Objective To prospectively compare high-resolution ultrasonography (US) and nerve conduction velocity (NCV) in clinically diagnosed mild carpal tunnel syndrome (CTS). Methods Eighty-five patients (70 women and 15 men, mean age 46.8 years) reported symptoms compatible with classic/probable CTS. The protocol included NCV of the median and ulnar nerves (distal motor latency [DML], sensory conduction velocity [SCV] from the third [M3 SCV] and fourth fingers [M4 SCV] to the wrist for the median nerve); electrophysiologic severity scale; self-administered Levine/Boston questionnaire (BQ); and cross-sectional area (CSA) measurement of the nerve at the tunnel inlet (CSA-I), at the middle (CSA-M), and at the outlet (CSA-O). Relationship between age, body mass index, duration of symptoms, CSAs, NCV, electrophysiologic severity scale, and BQ scores was calculated. Concordance between CSAs and NCV, sensitivity of NCV and US was also evaluated. Results The mean values of CSA-I, CSA-M, and CSA-O were 10.3, 9.8, and 8.7 mm2, respectively. Relationships were found between CSA-I and M3 SCV (r = −0.45), M4 SCV (r = −0.56), and median nerve DML (r = 0.29). Anomalous CSA-I, CSA-M, and CSA-O were found in 48, 25, and 26 patients, respectively; 55 (64.7%) had ≥1 abnormal CSA. NCV abnormalities were found in 67%. The sensitivity increased to 76.5% if US and NCV were considered together. The highest concordance to detect absence/presence of abnormalities was between CSA-I and NCV (77.6%; κ = 0.52). Conclusion In mild cases of CTS, US did not detect more anomalies than NCV and vice versa, and no anomalies were detected with either diagnostic instrument in 23.5% of mild cases.