154 research outputs found
Short-term adaptations following Complex Training in team-sports: A meta-analysis
Objective. The purpose of this meta-analysis was to study the short-term adaptations on sprint and vertical jump (VJ) performance following Complex Training (CT) in team-sports. CT is a resistance training method aimed at developing both strength and power, which has a direct effect on sprint and VJ. It consists on alternating heavy resistance training exercises with plyometric/power ones, set for set, on the same workout. Methods. A search of electronic databases up to July 2016 (PubMed-MEDLINE, SPORTDiscus, Web of Knowledge) was conducted. Inclusion criteria: 1) at least one CT intervention group; 2) training protocols â„4-wks; 3) sample of team-sport players; 4) sprint or VJ as an outcome variable. Effect sizes (ES) of each intervention were calculated and subgroup analyses were performed. Results. A total of 9 studies (13 CT groups) met the inclusion criteria. Medium effect sizes (ES) (ES = 0.73) were obtained for pre-post improvements in sprint, and small (ES = 0.41) in VJ, following CT. Experimental-groups presented better post-intervention sprint (ES = 1.01) and VJ (ES = 0.63) performance than control-groups. Sprint. Large ESs were exhibited in younger athletes (12 total sessions (ES = 0.74). VJ. Large ESs in programs with >12 total sessions (ES = 0.81). Medium ESs obtained for under-Division I individuals (ES = 0.56); protocols with intracomplex rest intervals â„2 min (ES = 0.55); conditioning activities with intensities â€85% 1RM (ES = 0.64); basketball/volleyball players (ES = 0.55). Small ESs were found for younger athletes (ES = 0.42); interventions â„6 weeks (ES = 0.45). Conclusions. CT interventions have positive medium effects on sprint performance and small effects on VJ in team-sport athletes. This training method is a suitable option to include in the season planning
Comparison of two 8-week training interventions on the athletic performance of padel players
Padel is an intermittent racket sport played in pairs (2 vs. 2) on a small-sized grass court (20 x 10 m), involving high physical fitness demands for the players. Therefore, this study aims to compare the effect of two 8-week in-season training programs on the athletic performance of male padel players. Participants (age, 22.1±0.8 yr; body height, 182.0±1.0 cm ; body mass, 74.7±0.7 kg) were randomly assigned to the integrated training group (IG, n=12) and non-integrated training group (NIG, n=12). The IG trained inside the padel court, integrating neuromuscular exercises with sport-specific (i.e., use of the racket) technical actions. The NIG trained outside the padel court, performing the same neuromuscular exercises and sport-specific technical actions as the IG, although not simultaneously. Before and after the intervention, athletes were assessed for their hand-grip strength, two legged and one-legged Abalakov jump, bench press performance, padel stroke velocity, cardiorespiratory endurance (30-15IFT), 5-m and 10-m linear sprint time and change of direction ability at 90Âș and 180Âș using left and right leg. Both groups improved their scores on Abalakov jump tests, bench press performance, stroke velocity, cardiorespiratory endurance (30-15IFT), and change of direction ability at 90Âș and 180Âș (all changes p<.05; effect size = 0.22-2.58). The IG improved stroke velocity compared to NIG (p<.05), and only the IG showed pre-post improvements (p<.05; effect size = 0.30-0.76) in change of direction ability at 90Âș and 180Âș involving the non-dominant leg (i.e., turn to the right). An 8-week in-season integrated training approach and a non-integrated training approach may induce similar improvements in athletic performance among highly trained male padel players. However, the neuromuscular training program involving an integration of padel-specific and non-specific training exercises may induce greater improvements in padel-specific performance (i.e., stroke velocity) and change of direction speed ability, particularly in movements involving the non-dominant leg
The effect of substrate on high-temperature annealing of GaN epilayers: Si versus sapphire
Influence of physical and technical aspects on change of direction performance of rugby players: An exploratory study
We examined the relationships between change of direction (COD) speed and deficit, and a series of speed-and power-related measurements in national team rugby union players and analyzed the influence of movement patterns on COD ability. Eleven male athletes completed the following physical assessments on different days: day 1âanthropometric measurements, and lower-body kinematic parameters (assessed with eight inertial sensors) and completion time in COD tests (proagility, 45⊠cutting maneuver (CUT), and âLâ (L-Drill)); day 2âbilateral and unilateral squat and countermovement jumps, 40 m linear sprint, and bar-power output in the jump squat and half-squat exercises. Pearsonâs productâmoment correlations were performed to determine the relationships between COD velocities, COD deficits, and the speedâpower variables. Differences between players with higher and lower COD deficits were examined using magnitude-based inferences. Results showed that (1) greater sprint momentum was associated with higher COD deficits, particularly in drills with sharper angles and multiple directional changes (L-drill and pro-agility); (2) higher unilateral jump heights were associated with greater COD deficits in the pro-agility and L-drill but not in the CUT; (3) faster athletes were less efficient at changing direction and presented greater trunk and knee flexion angles during COD maneuvers, probably as a consequence of higher inertia
Emission polarization control in semiconductor quantum dots coupled to a photonic crystal microcavity
8 pĂĄginas, 5 figuras.-- OCIS codes: (160.4760) Optical properties; (230.5298) Photonic crystals; (230.5590) Quantumwell,
-wire and âdot devices.We study the optical emission of single semiconductor quantum dots weakly coupled to a photonic-crystal micro-cavity. The linearly polarized emission of a selected quantum dot changes continuously its polarization angle, from nearly perpendicular to the cavity mode polarization at large detuning, to parallel at zero detuning, and reversing sign for negative detuning. The linear polarization rotation is qualitatively interpreted in terms of the detuning dependent mixing of the quantum dot and cavity states. The present result is relevant to achieve continuous control of the linear polarization in single photon emitters.This
work has been supported by research contracts of the Spanish Ministry of Education Grants
MAT2008-01555/NAN, Consolider CSD 2006-19 and Naninpho-QD TEC2008-06756-C03-
01, and the Community of Madrid Grant Grant CAM (S2009/ESP-1503).Peer reviewe
The altered transcriptome and DNA methylation profiles of docetaxel resistance in breast cancer PDX models
Taxanes are standard therapy in clinical practice for metastatic breast cancer; however, primary or acquired chemoresistance are a common cause of mortality. Breast cancer patient-derived xenografts (PDX) are powerful tools for the study of cancer biology and drug treatment response. Specific DNA methylation patterns have been associated to different breast cancer subtypes but its association with chemoresistance remains unstudied. Aiming to elucidate docetaxel resistance mechanisms, we performed genome-wide DNA methylation in breast cancer PDX models, including luminal and triple-negative breast cancer (TNBC) models sensitive to docetaxel, their matched models after emergence of chemoresistance and residual disease after short-term docetaxel treatment. We found that DNA methylation profiles from breast cancer PDX models maintain the subtype-specific methylation patterns of clinical samples. Two main DNA methylation clusters were found in TNBC PDX and remain stable during the emergence of docetaxel resistance; however, some genes/pathways were differentially methylated according to docetaxel response. A DNA methylation signature of resistance able to segregate TNBC based on chemotherapy response was identified. Transcriptomic profiling of selected sensitive/resistant pairs and integrative analysis with methylation data demonstrated correlation between some differentially methylated and expressed genes in docetaxel-resistant TNBC PDX models. Multiple gene expression changes were found after the emergence of docetaxel resistance in TNBC. DNA methylation and transcriptional changes identified between docetaxel-sensitive and -resistant TNBC PDX models or residual disease may have predictive value for chemotherapy response in TNBC. IMPLICATIONS: Subtype-specific DNA methylation patterns are maintained in breast cancer PDX models. While no global methylation changes were found, we uncovered differentially DNA methylated and expressed genes/pathways associated with the emergence of docetaxel resistance in TNBC
The contribution of Real Madridâs first five European Cups to the emergence of a common football space
Real Madrid won the first five editions of the European Champion Clubsâ Cup (now formally known as the UEFA Champions League, and to which we will refer hereon as the European Cup) between 1956 and 1960, contributing decisively to the competitionâs consolidation. The tournamentâs history started towards the end of 1954, when a journalist of the French sports daily LâĂquipe, Gabriel Hanot, published an article arguing the need to organise a competition that could bring together the champions of every European league. However, this was not an original proposal. Thirty years before Hanotâs article proposals for such a football competition were circulated among the gameâs ruling elite. Unfortunately, at that time the lack of a good transport infrastructure to travel through Europe discouraged the proposers which, instead, turned their attention to regional supranational competitions, such as the Mitropa Cup or the Latin Cup. The first five editions of the European Cup witnessed as many victories of Real Madrid, thus forging an indissoluble bond between the competition and the Spanish club. These five European titles did not only cement the supremacy of Real Madrid on the pitch as a great football team, but they also contributed to the consolidation of the European Cup itself in the publicâs imaginary. We also argue that given the expectations raised by Real Madridâs triumphs across Europe those matches might have contributed as well to the emergence of a European football space. Since 1955 Real Madrid occupied an ever increasing space in the press across Europe. Real Madrid was then considered as the best expression of modernity in football. This chapter aims to analyse the meaning of these five European Cup titles for the emergence and definition of a nascent European football space. We, of course, also question whether such a common space can be found. The chapter explores in depth the reasons behind Real Madridâs enthusiasm with the new European competition. We also examine the social impact that Real Madridâs hegemony in the European Cup had in the context of Spainâs international isolation during General Francoâs dictatorship (1939-1975). In order to achieve the above mentioned objectives, the chapter relies on thematic analysis of selected publications in the Spanish and British press during those years. Moreover, we have also relied on a review of academic literature on the role of Real Madrid during the Franco dictatorship years, mainly the 1950s and 60s. This chapter is part of wider on-going research. In this research we examine the content of two Spanish dailies (ABC and Marca) and three British newspapers (The Guardian, The Times and the Daily Mirror). We searched these newspapers for content related to Real Madrid on specific dates: The semifinal games (two legs) and the final of each one of the five years where Real Madrid won the European Cup. We searched for content the day of each match, the day before and two days after each one of the matches. This chapter is a presentation of the findings obtained through thematic analysis of the data obtained through those searches
Multicentric study on malignant pleural mesothelioma and non-occupational exposure to asbestos
Insufficient evidence exists on the risk of pleural mesothelioma from non-occupational exposure to asbestos. A population-based caseâcontrol study was carried out in six areas from Italy, Spain and Switzerland. Information was collected for 215 new histologically confirmed cases and 448 controls. A panel of industrial hygienists assessed asbestos exposure separately for occupational, domestic and environmental sources. Classification of domestic and environmental exposure was based on a complete residential history, presence and use of asbestos at home, asbestos industrial activities in the surrounding area, and their distance from the dwelling. In 53 cases and 232 controls without evidence of occupational exposure to asbestos, moderate or high probability of domestic exposure was associated with an increased risk adjusted by age and sex: odds ratio (OR) 4.81, 95% confidence interval (CI) 1.8â13.1. This corresponds to three situations: cleaning asbestos-contaminated clothes, handling asbestos material and presence of asbestos material susceptible to damage. The estimated OR for high probability of environmental exposure (living within 2000 m of asbestos mines, asbestos cement plants, asbestos textiles, shipyards, or brakes factories) was 11.5 (95% CI 3.5â38.2). Living between 2000 and 5000 m from asbestos industries or within 500 m of industries using asbestos could also be associated with an increased risk. A doseâresponse pattern appeared with intensity of both sources of exposure. It is suggested that low-dose exposure to asbestos at home or in the general environment carries a measurable risk of malignant pleural mesothelioma. © 2000 Cancer Research Campaig
Proportionate flow shop games
htmlabstractIn a proportionate flow shop problem several jobs have to be processed through a fixed sequence of machines and the processing time of each job is equal on all machines. By identifying jobs with agents, whose costs linearly depend on the completion time of their jobs, and assuming an initial processing order on the jobs, we face two problems: the first one is how to obtain an optimal order that minimizes the total processing cost, the second one is how to allocate the cost savings obtained by ordering the jobs optimally. In this paper we focus on the allocation problem. PFS games are defined as cooperative games associated to proportionate flow shop problems. It is seen that PFS games have a nonempty core. Moreover, it is shown that PFS games are convex if the jobs are initially ordered in decreasing urgency. For this case an explicit game independent expression for the Shapley value is provid
Change of direction deficit in national team rugby union players: is there an Influence of playing position?
The aim of this study was to investigate the change of direction (COD) ability and deficits of elite rugby union players, discriminating between position (backs and forwards), and between "faster and slower players", in multiple COD tasks. Twenty-four male rugby union players from the Brazilian senior National team completed the following assessments: Squat and countermovement jumps; drop jump; standing long jump, horizontal triple jumps; 40-m linear sprint; Pro-agility, L-Drill, and Zig-zag COD tests; and squat 1-repetition maximum. The differences between backs and forwards and between faster and slower performers were examined using magnitude-based inferences. Backs were faster (in both linear and COD speed tests) and jumped higher than forwards. Moreover, they generated an inferior sprint momentum. No differences were found in COD deficit between playing positions. However, when dividing the sample by median split, faster players outperformed their slower counterparts in all powerâ»speed variables and presented higher COD deficits. These results suggest that separating rugby players by playing position might not discriminate players with different COD skills and that the median split analysis is more sensitive to identifying these differences. Furthermore, the present data indicate that faster rugby players are less efficient at changing direction and tolerating higher approach velocities in COD maneuvers
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