Audio/Video Transmission over IEEE 802.11e Networks: Retry Limit Adaptation and Distortion Estimation

The objective of this thesis focuses on the audio and video transmission over wireless networks adopting the family of the IEEE 802.11x standards. In particular, this thesis discusses about the resolution of four issues: the adaptive retransmission, the comparison of video quality indexes for retry limit adaptation purposes, the estimation of the distortion and the joint adaptation of the maximum number of retransmissions of voice and video flows

Use of different marker pre-selection methods based on single SNP regression in the estimation of Genomic-EBVs

Two methods of SNPs pre-selection based on single marker regression for the estimation of genomic breeding values (G-EBVs) were compared using simulated data provided by the XII QTL-MAS workshop: i) Bonferroni correction of the significance threshold and ii) Permutation test to obtain the reference distribution of the null hypothesis and identify significant markers at P<0.01 and P<0.001 significance thresholds. From the set of markers significant at P<0.001, random subsets of 50% and 25% markers were extracted, to evaluate the effect of further reducing the number of significant SNPs on G-EBV predictions. The Bonferroni correction method allowed the identification of 595 significant SNPs that gave the best G-EBV accuracies in prediction generations (82.80%). The permutation methods gave slightly lower G-EBV accuracies even if a larger number of SNPs resulted significant (2,053 and 1,352 for 0.01 and 0.001 significance thresholds, respectively). Interestingly, halving or dividing by four the number of SNPs significant at P<0.001 resulted in an only slightly decrease of G-EBV accuracies. The genetic structure of the simulated population with few QTL carrying large effects, might have favoured the Bonferroni method

Effects of Flavonoids on Cancer, Cardiovascular and Neurodegenerative Diseases: Role of NF-κB Signaling Pathway

Flavonoids are polyphenolic phytochemical compounds found in many plants, fruits, veg- etables, and leaves. They have a multitude of medicinal applications due to their anti-inflammatory, antioxidative, antiviral, and anticarcinogenic properties. Furthermore, they also have neuroprotec- tive and cardioprotective effects. Their biological properties depend on the chemical structure of flavonoids, their mechanism of action, and their bioavailability. The beneficial effects of flavonoids have been proven for a variety of diseases. In the last few years, it is demonstrated that the effects of flavonoids are mediated by inhibiting the NF-κB (Nuclear Factor-κB) pathway. In this review, we have summarized the effects of some flavonoids on the most common diseases, such as cancer, car- diovascular, and human neurodegenerative diseases. Here, we collected all recent studies describing the protective and prevention role of flavonoids derived from plants by specifically focusing their action on the NF-κB signaling pathway

Joint Voice/Video Retry Limit Adaptation for On-Demand Streaming over WiFi Networks

This letter proposes a fast retry limit adaptation algorithm for the 802.11e distributed networks. Different from existing solutions, which manage a unique access category, the presented method jointly estimates the retry limits associated with both voice and video packets. The algorithm that operates in saturated and non-saturated traffic conditions is validated adopting an 802.11n physical layer and comparing its performance with a proper extension of an existing solution

A real-time 3D reconstruction of staircases for rehabilitative exoskeletons

In medical contexts, the use of assistive exoskeletons for the rehabilitation of people with impaired mobility represents a common practice. Recent advances suggest that, soon, such mechatronic systems will also be used to assist people in their everyday life. In order to reach such target, exoskeletons must become able to perceive the environment. To this purpose, a system for the parametric identification of a staircase is proposed in this paper. More precisely, given a staircase of unknown geometry, the system identifies its 3D shape. Furthermore, it also estimates the reciprocal orientation and distance between the exoskeleton and the staircase. Differently from other approaches, this result is achieved by means of low cost devices: an inertial measurement unit, two ranging sensors, and an Arm-Cortex processor. Starting from the ranging sensors acquisitions, the staircase model is identified in real time, during the execution of a step. The proposed procedure is based on an extended recursive total least squares strategy, in order to fully exploit the computational capabilities of the Arm processor, and it is characterized by execution times smaller than 10 −3 s. The estimation algorithm has been tested on an actual exoskeleton and the resulting experimental outcomes are compared with the results obtained through alternative methods

SESSION-RPE IS A VALUABLE INTERNAL LOAD EVALUATION METHOD IN BEACH VOLLEYBALL FOR BOTH GENDERS, ELITE AND AMATEUR PLAYERS, CONDITIONING AND TECHNICAL SESSIONS, BUT LIMITED FOR TACTICAL TRAINING AND GAMES

This study aimed to verify the validity of session-RPE method to monitor the internal training load (ITL) in beach volleyball players by considering sessions related to different genders, competition levels (elite or amateur), and types of session (conditioning, technical, or tactical/game). Session-RPE and Edwards’ methods were applied to quantify the ITLs of 12 elite (18 players; 197 individual sessions) and 12 amateur (18 players;189 individual sessions) training sessions. Very large relationships between the two methods emerged for both competition level (Elite: r=.77; Amateur: r=.75) and gender (male: r=.76; female: r=.75) subgroups, and conditioning sessions (r=.75). Large relationships emerged for technical (r=.61) sessions, whereas tactical/game sessions resulted only in moderate relationships (r=.36). Beach volleyball coaches could adequately use session-RPE method to monitor training for players of different genders, competition levels, and types of session, although tactical/game sessions should be considered with some caution

The relative age effect is larger in Italian soccer top-level youth categories and smaller in Serie A

The relative age effect (RAE; i.e., an asymmetry in the birth distribution) is a bias observed in sport competitions that may favour relatively older athletes in talent identification. Therefore, the aim of this study was to investigate the presence of RAE in elite soccer players competing in the Italian championships, even considering the discriminations of younger and older Serie A players (in relation to the median age of the sample), and different positional roles (i.e., goalkeeper, defender, midfielder, forward) for each observed category. A total of 2051 players competing into the 2017\u20132018 Italian under-15 (n = 265), under-16 (n = 362), under-17 (n = 403), Primavera (n = 421) and Serie A (n = 600) championships were analysed. The birth-date distributions, grouped in four quartiles (i.e., January-March, Q1; April-June, Q2; July-September, Q3; October-December, Q4), were compared to a uniform distribution using Chi-squared analysis. The week of birth was analysed using Poisson regression. The results showed a large over-representation of players born in Q1 in all soccer player categories. However, the effect size of this trend resulted smaller as age increased. Individuals born in Q1 have about two-folds more chances to become a Serie A player compared to those born in Q4. The Poisson regression analysis showed that RAE was greater for defenders than for forwards among all categories. Therefore, a strongly biased selection emerged among elite soccer players competing in Italian championships, highlighting how young individuals born in the first three months have many more chances to become elite players compared to the others

Running technique is more effective than soccer-specific training for improving the sprint and agility performances with ball possession of prepubescent soccer players

Soccer-specific training is easily associable to players\u2019 sprint abilities demonstrated during a match. However, no clear evidence has been provided to show whether this approach is more effective than training focused on running techniques for sprints in prepubescent soccer players. Thus, the present study aimed at comparing the effects of these two training approaches on prepubescent soccer players\u2019 sprint performances. Ninety-five players (10\ub12 years) competing in local (Piedmont, Italy) Under-9 (N=21), -10 (N=24), -11 (N=25) and -13 (N=25) championships were recruited for the study. Sixty-three and 32 players were included in the running training group (RTG) and soccer-specific group (SSG), respectively. Before (PRE) and after (POST) the training period (2 weekly sessions for 12 weeks), sprint abilities were evaluated by means of four 20-m sprint tests: linear sprint (20-mL), linear sprint with ball possession (20-mLB), sprint with change of direction (20- mCoD), sprint with change of direction and with ball possession (20-mCoDB). A linear mixed model was applied to evaluate differences (P 640.05) between the RTG and SSG in the four tests and categories, comparing PRE and POST performances. A main effect emerged for the interaction between groups, sessions (p=0.014; Between PRE ES range=0.03, 0.85; Within PRE-POST ES range=-0.45, 0.09), highlighting a POST improvement of RTG for the 20-mLB ( 06=-7.9%; ES=0.85) and 20-mCoDB ( 06=-5.9%; ES=0.33). In contrast, no improvements emerged for the SSG. The present findings indicate that the training approach of the RTG is more able to improve prepubescent soccer players\u2019 sprint performances than that of the SSG, with the emphasis on ball possession executions, which are particularly game-related