288 research outputs found
Influence of the area per player in non-professional soccer players: A pilot study focused on positional roles
This study analyses the influence of different area per player (AP; 75, 98 and 131 m2 ) on the average metabolic power (MP) and other soccer-related performance variables in relation to the positional roles. We recruited 19 non-professional male soccer players (25.2 ± 6.3 y; 23.7 ± 2.3 kg/m2; 16.4 ± 6.3 y soccer experience) to play three different small-sided games (SSGs): SSG1 (5 vs. 5; 30 × 30 m; 5 min), SSG2 (5 vs. 5; 35 × 45 m; 5 min) and SSG3 (7 vs. 7; 35 × 45 m; 8 min). Specific playing rules were applied. GPS-assessed soccer-related variables were: average MP (AMP), distance covered in 1 min (DIS); % time spent at high speed (v > 16 km/h; % hst) or MP (>20 W/kg; % hmpt); % distance covered at high positive/negative speed (2 < v < 4 m/s2, % ACC; −6 < v < −2 m/s2, % DEC); and number of actions at high MP (hmpa). All recorded variables differed when each SSG was compared to the others (p < 0.05), but for hmpa for attackers. Most performance variables were positively associated with increasing AP (p < 0.05), but for % ACC and % DEC, and differed among positional roles within the same SSG (p < 0.05). Here the general applicability of SSGs, regardless the physical/technical skills of the group of players, to enhance performance is confirmed; furthermore, quantitative advices on AMP and other performance variables are provided to achieve significant improvements in all soccer players of the team
Regular football training down-regulates miR-1303 muscle expression in veterans
Purpose: Regular exercise affects the expression of several genes, proteins and microRNAs (miRNAs) in time- and intensity-dependent manner promoting longevity. We previously identified from GeneChip Array analysis several differentially expressed genes and miRNAs in muscle from veteran football players (VPG) compared to active untrained elderly subjects (CG); here we focussed on miRNA-1303 (miR-1303). The aims of the present research were: to analyse the effects of football training on the expression of miR-1303 and to identify its putative target involved in the longevity pathways in skeletal muscle from VPG compared to CG. Methods: RNA samples from 12 VPG and 12 CG muscle biopsies were used to validate miR-1303 expression. Crossing four different bioinformatic algorithms, we identified 16 putative targets of miR-1303; from these, BAG-2, KLHL7 and KBTBD6 were chosen for further validation by Western blot analysis in LHCN-M2 human myoblasts transiently transfected with miR-1303. Results: Football training down-regulates miR-1303 expression in muscle from VPG compared to CG and the expression of BAG-2, a chaperon protein involved in the autophagy pathway, inversely correlated to overexpression of miR-1303 in a time-dependent manner, indicating that it is a miR-1303 potential target. Conclusions: This is the first report, to our knowledge, describing miR-1303 regulation in skeletal muscle by football training and the identification of a target protein, BAG-2, involved in the autophagy pathway. This result contributes to the enlargement of knowledge on the molecular mechanisms linking football training, autophagy and longevity
Submarine Geomorphology and Sedimentary Features around the Egadi Islands (Western Mediterranean Sea)
The physiography, the geomorphological features and the sedimentary bedforms offshore Egadi Islands (Italy) have been illustrated and mapped through an integrated analysis of high-resolution bathymetric, seismo-acoustic and sedimentological data. The study area is characterized by a wide, up to 25 km, continental shelf which is separated by a NNW trending linear incision, the Marettimo Channel, along which several erosional and depositional features have been detected and mapped. Sedimentary prograding wedges were detected at water depths between 100-125 m along the shelf margin, which accumulated during sea level fall and lowstand stages of the last glacio-eustatic cycle (post- MIS 5.5). The study detected several slope breaks defining scarps across the continental shelf, which were interpreted as coastal cliffs that originated during the post-LGM eustatic sea level rise. Several fields of different types of sedimentary bedforms, including 2-D and 3-D hydraulic dunes and sorted bedforms, were found across the continental shelf, providing evidence of a high hydrodynamic regime affecting the seafloor. Further on, the study recognized erosive and depositional features related to bottom currents (contourites) in the Marettimo Channel.
These findings provide a better understanding of the morpho-sedimentary evolution of the Egadi Islands offshore in the latest Quaternary. Moreover, they offer essential scientific support for effectively managing the most valuable priority habitats for conservation , such as Posidonia oceanica meadow and coralline algae bioconstructions (Coralligenous habitat)
Characteristics of drug-resistant tuberculosis in Abkhazia (Georgia), a high-prevalence area in Eastern Europe
Although multidrug-resistant (MDR) tuberculosis (TB) is a major public health problem in Eastern Europe, the factors contributing to emergence, spread and containment of MDR-TB are not well defined. Here, we analysed the characteristics of drug-resistant TB in a cross-sectional study in Abkhazia (Georgia) between 2003 and 2005, where standard short-course chemotherapy is supplemented with individualized drug-resistance therapy. Drug susceptibility testing (DST) and molecular typing were carried out for Mycobacterium tuberculosis complex strains from consecutive smear-positive TB patients. Out of 366 patients, 60.4% were resistant to any first-line drugs and 21% had MDR-TB. Overall, 25% of all strains belong to the Beijing genotype, which was found to be strongly associated with the risk of MDR-TB (OR 25.9, 95% CI 10.2-66.0) and transmission (OR 2.8, 95% CI 1.6-5.0). One dominant MDR Beijing clone represents 23% of all MDR-TB cases. The level of MDR-TB did not decline during the study period, coinciding with increasing levels of MDR Beijing strains among previously treated cases. Standard chemotherapy plus individualized drug-resistance therapy, guided by conventional DST, might be not sufficient to control MDR-TB in Eastern Europe in light of the spread of "highly transmissible" MDR Beijing strains circulating in the community
First LOFAR results on galaxy clusters
Deep radio observations of galaxy clusters have revealed the existence of
diffuse radio sources related to the presence of relativistic electrons and
weak magnetic fields in the intracluster volume. The role played by this
non-thermal intracluster component on the thermodynamical evolution of galaxy
clusters is debated, with important implications for cosmological and
astrophysical studies of the largest gravitationally bound structures of the
Universe. The low surface brightness and steep spectra of diffuse cluster radio
sources make them more easily detectable at low-frequencies. LOFAR is the first
instrument able to detect diffuse radio emission in hundreds of massive galaxy
clusters up to their formation epoch. We present the first observations of
clusters imaged by LOFAR and the huge perspectives opened by this instrument
for non-thermal cluster studies.Comment: Proceedings of the 2012 week of the French Society of Astronomy and
Astrophysics (SF2A) held in Nice, June 5th-8t
Combining Private Set-Intersection with Secure Two-Party Computation
Private Set-Intersection (PSI) is one of the most popular and practically relevant secure two-party computation (2PC) tasks. Therefore, designing special-purpose PSI protocols (which are more efficient than generic 2PC solutions) is a very active line of research. In particular, a recent line of work has proposed PSI protocols based on oblivious transfer (OT) which, thanks to recent advances in OT-extension techniques, is nowadays a very cheap cryptographic building block.
Unfortunately, these protocols cannot be plugged into larger 2PC applications since in these protocols one party (by design) learns the output of the intersection. Therefore, it is not possible to perform secure post-processing of the output of the PSI protocol.
In this paper we propose a novel and efficient OT-based PSI protocol that produces an encrypted output that can therefore be later used as an input to other 2PC protocols. In particular, the protocol can be used in combination with all common approaches to 2PC including garbled circuits, secret sharing and homomorphic encryption. Thus, our protocol can be combined with the right 2PC techniques to achieve more efficient protocols for computations of the form for arbitrary functions
First LOFAR observations at very low frequencies of cluster-scale non-thermal emission: the case of Abell 2256
Abell 2256 is one of the best known examples of a galaxy cluster hosting
large-scale diffuse radio emission that is unrelated to individual galaxies. It
contains both a giant radio halo and a relic, as well as a number of head-tail
sources and smaller diffuse steep-spectrum radio sources. The origin of radio
halos and relics is still being debated, but over the last years it has become
clear that the presence of these radio sources is closely related to galaxy
cluster merger events. Here we present the results from the first LOFAR Low
band antenna (LBA) observations of Abell 2256 between 18 and 67 MHz. To our
knowledge, the image presented in this paper at 63 MHz is the deepest ever
obtained at frequencies below 100 MHz in general. Both the radio halo and the
giant relic are detected in the image at 63 MHz, and the diffuse radio emission
remains visible at frequencies as low as 20 MHz. The observations confirm the
presence of a previously claimed ultra-steep spectrum source to the west of the
cluster center with a spectral index of -2.3 \pm 0.4 between 63 and 153 MHz.
The steep spectrum suggests that this source is an old part of a head-tail
radio source in the cluster. For the radio relic we find an integrated spectral
index of -0.81 \pm 0.03, after removing the flux contribution from the other
sources. This is relatively flat which could indicate that the efficiency of
particle acceleration at the shock substantially changed in the last \sim 0.1
Gyr due to an increase of the shock Mach number. In an alternative scenario,
particles are re-accelerated by some mechanism in the downstream region of the
shock, resulting in the relatively flat integrated radio spectrum. In the radio
halo region we find indications of low-frequency spectral steepening which may
suggest that relativistic particles are accelerated in a rather inhomogeneous
turbulent region.Comment: 13 pages, 13 figures, accepted for publication in A\&A on April 12,
201
Polarized point sources in the LOFAR Two-meter Sky Survey: A preliminary catalog
The polarization properties of radio sources at very low frequencies (h45m–15h30m right ascension, 45°–57° declination, 570 square degrees). We have produced a catalog of 92 polarized radio sources at 150 MHz at 4.′3 resolution and 1 mJy rms sensitivity, which is the largest catalog of polarized sources at such low frequencies. We estimate a lower limit to the polarized source surface density at 150 MHz, with our resolution and sensitivity, of 1 source per 6.2 square degrees. We find that our Faraday depth measurements are in agreement with previous measurements and have significantly smaller errors. Most of our sources show significant depolarization compared to 1.4 GHz, but there is a small population of sources with low depolarization indicating that their polarized emission is highly localized in Faraday depth. We predict that an extension of this work to the full LOTSS data would detect at least 3400 polarized sources using the same methods, and probably considerably more with improved data processing
!CHAOS: A cloud of controls
The paper is aimed to present the !CHAOS open source project
aimed to develop a prototype of a national private Cloud Computing infrastructure, devoted to accelerator control systems and large experiments of High Energy Physics (HEP). The !CHAOS project has been financed by MIUR (Italian Ministry of Research and Education) and aims to develop a new concept of control system and data acquisition framework by providing, with a high level of abstraction, all the services needed for controlling and managing a large scientific, or non-scientific, infrastructure. A beta version of the !CHAOS infrastructure will be released at the end of December 2015 and will run on private Cloud infrastructures based on OpenStack
Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use.
Tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders1. They are heritable2,3 and etiologically related4,5 behaviors that have been resistant to gene discovery efforts6-11. In sample sizes up to 1.2 million individuals, we discovered 566 genetic variants in 406 loci associated with multiple stages of tobacco use (initiation, cessation, and heaviness) as well as alcohol use, with 150 loci evidencing pleiotropic association. Smoking phenotypes were positively genetically correlated with many health conditions, whereas alcohol use was negatively correlated with these conditions, such that increased genetic risk for alcohol use is associated with lower disease risk. We report evidence for the involvement of many systems in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission. The results provide a solid starting point to evaluate the effects of these loci in model organisms and more precise substance use measures
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