261 research outputs found
Fatigue-Induced Balance Impairment in Young Soccer Players
No full textContext: Although balance is generally recognized to be an important feature in ensuring good performance in soccer, its link with functional performance remains mostly unexplored, especially in young athletes.
Objective: To investigate changes in balance induced by fatigue for unipedal and bipedal static stances in young soccer players.
Design: Crossover study.
Setting: Biomechanics laboratory and outdoor soccer field.
Patients or Other Participants: Twenty-one male soccer players (age = 14.5 ± 0.2 years, height = 164.5 ± 5.6 cm, mass = 56.8 ± 6.8 kg).
Intervention(s): Static balance was assessed with postural-sway analysis in unipedal and bipedal upright stance before and after a fatigue protocol consisting of a repeated sprint ability (RSA) test (2 × 15-m shuttle sprint interspersed with 20 seconds of passive recovery, repeated 6 times).
Main Outcome Measure(s): On the basis of the center of pressure (COP) time series acquired during the experimental tests, we measured sway area, COP path length, and COP maximum displacement and velocity in the anteroposterior and mediolateral directions.
Results: Fatigue increased all sway values in bipedal stance and all values except COP velocity in the mediolateral direction in unipedal stance. Fatigue index (calculated on the basis of RSA performance) was positively correlated with fatigue/rest sway ratio for COP path length and COP velocity in the anteroposterior and mediolateral directions for nondominant single-legged stance.
Conclusions: Fatigued players exhibited reduced performance of the postural-control system. Participants with better performance in the RSA test appeared less affected by balance impairment, especially in single-legged stance
Interactive and Robust Mesh Booleans
No full textBoolean operations are among the most used paradigms to create and edit
digital shapes. Despite being conceptually simple, the computation of mesh
Booleans is notoriously challenging. Main issues come from numerical
approximations that make the detection and processing of intersection points
inconsistent and unreliable, exposing implementations based on floating point
arithmetic to many kinds of degeneracy and failure. Numerical methods based on
rational numbers or exact geometric predicates have the needed robustness
guarantees, that are achieved at the cost of increased computation times that,
as of today, has always restricted the use of robust mesh Booleans to offline
applications. We introduce the first algorithm for Boolean operations with
robustness guarantees that is capable of operating at interactive frame rates
on meshes with up to 200K triangles. We evaluate our tool thoroughly,
considering not only interactive applications but also batch processing of
large collections of meshes, processing of huge meshes containing millions of
elements and variadic Booleans of hundreds of shapes altogether. In all these
experiments, we consistently outperform prior art by at least one order of
magnitude
Sprint vs. intermittent training young female basketball players
No full textThis study aimed at comparing the effects of intermittent and repeated sprint ability training on physiological variables.Sixteen young female basketball players were randomly allocated to intermittent training (IT=8) or repeated sprint ability training (RST=8) groups. The following outcomes were measured at baseline and after 6 weeks of training: Yo-Yo intermittent recovery (Yo-Yo) and repeated sprint ability (RSA) tests.For all the variables investigated the effect of training type showed a different trend respect at current knowledge. In the RSA, best time (BT) was a significant main effect of training time (pre- vs. post-) (P<0.0001), and of the interaction training type/time (P=0.03). The RST showed a decrease in BT of 3.1\% (P=0.005) while the IT showed a decrease of 6.2\% (P<0.0001). In the IT there was a significant main effect of time for the total distance with an increment of 26.9\%, and a significant main effect of time in the final speed with an increment of 1.23\%.These findings suggest that the two training methods used in this study can be an effective training strategy for inducing anaerobic and basketball-specific training schedules. Besides, even when IT training is not done at very high speed, it can increase the maximum speed of the RSA
Analisi della diversità genetica in germoplasma sardo di orzo (Hordeum vulgare) mediante l'uso di marcatori molecolari RAPD
No full textGenotype by environment interactions in barley (Hordeum vulgare L.): different responses of landraces, recombinant inbred lines and varieties to Mediterranean environment
No full textGenotype-by-environment interactions (GEIs) can affect breeding progress because they often complicate the evaluation and selection of superior genotypes. This drawback can be reduced by gaining insights into GEI processes and genotype adaptation. Here, we have studied the GEIs over a set of 24 barley genotypes that were grown across six environments (location-by-year combinations) in Sardinia, Italy. Three groups of genotypes were analysed: barley landraces (LANs), recombinant inbred lines (RILs), and commercial varieties (VARs). The additive main effects and multiplicative interaction (AMMI) model was used for data analysis, and results evidenced no significant differences in grain yield averages for the 24 genotypes. However, there was a relevant GEI for yield mainly between two of the six environments (one characterised by warm pre-anthesis period and high spring rainfalls, and the other characterised by opposite features) and two groups of genotypes (VAR and LAN). Moreover, a negative trade-off between yield levels of genotypes was seen when the barley genotypes were grown in the contrasting environments. Overall, intermediate GEI levels were seen for RILs in comparison to LANs and VARs, and some of the RILs provided valuable yield levels (e.g. RILs 23 and 52). The results thus show the potential usefulness of LANs as a genetic resource for breeding, e.g. to obtain genotypes adapted to Mediterranean environments, such as the RILs analysed in this study
A NLP pipeline for the automatic extraction of microorganisms names from microbiological notes
No full textAccording to the 'Istituto Superiore di Sanita (ISS), hospital infections are the most frequent and serious complication of health care. This constitutes a real health emergency which requires incisive and joint action at all levels of the local and national health organization. Most of the valuable information related to the presence of a specific microorganism in the blood are written into the notes field of the laboratory exams results. The main objective of this work is to build a Natural Language Processing (NLP) pipeline for the automatic extraction of the names of microorganisms present in the clinical texts. A sample of 499 microbiological notes have been analysed with the developed system and all the microorganisms names have been extracted correctly, according to the labels given by the expert
Osservazioni su una popolazione locale sarda di orzo polistico (Hordeum vulgareL.)
No full textThe aim of the research has been the evaluation of a local population of barley (Hordeum vulgareL.) grown in
Sardinia. In 1989, 41 lines of the local population and 5 controi varieties («Arma», «Barberousse», «Gerbel», «Jaidor»
and «Pirate») were evaluated for agronomie and morphologic traits.The results have shown the presence of a considerable genetic variability in the local population, which is made
up of a miture of numerous genotypes. The lines showed an early stem extension and heading time compared to the
controls (5/3/89 vs 12/3/89 and 12/4/89 vs 17/4/89, respectively). The average values relative to Iodging index (3.2
vs 1.2), plant height (122.8 vs 108.4 cm) and 1,000 kernel weight (39.5 vs 27.2 g) were higher in thelines than in the
controls. The average yield of the lines was similar to that of the controls (3.46 vs 3.52 metric tons ha-1).Scopo della ricerca è stato la valutazione di una popolazione locale di orzo coltivata in Sardegna. Nel 1989, su
41 linee estratte a caso dalla popolazione locale e su 5 varietà di controllo («Arma», «Barberousse», «Gerbel», «Jaidon»
e «Pirate») sono stati rilevati ad Ottava (SS) una serie di caratteri agronomici e morfologici.I risultati hanno evidenziato la presenza di una variabilità genetica notevole entro la varietà agronomica che risulta
costituita da un miscuglio di numerosi genotipi. Rispetto alle varietà di controllo le linee sono state caratterizzate in
media da levata e spigatura anticipate, indice di allettamento, altezza del culmo e peso di 1000 cariossidi superiori. La
produzione media delle linee è risultata simile a quella delle varietà
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