85 research outputs found
Impact De La Volatilité De Change Sur La Performance FinanciÚre Des Entreprises Cotées
The main objective of this article is to measure and analyze the exchange rate volatility impact on the financial performance of Moroccan companies listed on Casablanca Stock Exchange during the last decade. We used linear models to study a sample of 56 companies. This paper prove the link between Dirham volatility and the companies financial performance, however this relationship was weak. In addition, we discussed the causes of this phenomenon and its managerial implications
LĂ©iomyosarcome utĂ©rin rĂ©cidivant: Ă propos dâun cas
Les léiomyosarcomes utérins sont des tumeurs malignes, rares, de mauvais pronostic. Nous rapportons un cas de léiomyosarcome diagnostiqué initialement à l'examen anapath d'une piÚce d'hystérectomie réalisée pour myome utérin chez une femme de 45 ans. Il s'agit d'une observation particuliÚre. La plupart des auteurs soulignent le mauvais pronostic précoce du léiomyosarcome avec récidive tumorale; Le principal facteur pronostique étant l'activité mitotique. La tumeur de notre patiente a une activité mitotique élevée, elle a récidivé trois fois en cinq ans et opérée à trois reprises.Key words: Léiomyosarcome, hystérectomie, pronostiqu
Effects of Walking Football During Ramadan Fasting on Heart Rate Variability and Physical Fitness in Healthy Middle-Aged Males
This study aimed to investigate the effect of a walking football (WF) program during Ramadan fasting (RF) on heart rate variability (HRV) indices, body composition, and physical fitness in middle-aged males. Thirty-one healthy sedentary men were randomized to WF ( n = 18) and control ( n = 13) groups. Both groups participated in RF. The WF group were involved in a training program (small-sided games) of three sessions a week during RF. The time and frequency domains of HRV, body composition, handgrip, lumbar strength, Modified Agility Test (MAT), and 6-minute walk test (6MWT) were measured before Ramadan (BR), during Ramadan (DR), and after Ramadan (AR). We reported that RF has significantly altered some parameters of HRV DR; the mean HR decreased while the mean RR, LF, and HF increased. WF had a significant effect on HRV and mean HR DR compared with BR and AR decreased while mean RR, HF and LF increased. DR, body mass decreased in both groups, while body mass index (BMI) decreased and lean mass increased only in WF group. Lower body mass and BMI levels were reported AR only in WF group. Physical capacity improved AR, compared with BR, only in the WF group with longer distance in 6MWT, shorter time(s) in MAT, and higher lumbar strength levels. We conclude that RF increases parasympathetic system activity. WF practice during RF is safe and might improve body composition, physical fitness, autonomic cardiac function, and physical fitness in middle-aged males
Training during the COVID-19 lockdown : knowledge, beliefs, and practices of 12,526 athletes from 142 countries and six continents
OBJECTIVE Our objective was to explore the training-related knowledge, beliefs, and practices of athletes and the influence of
lockdowns in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2).
METHODS Athletes (n = 12,526, comprising 13% world class, 21% international, 36% national, 24% state, and 6% recreational)
completed an online survey that was available from 17 May to 5 July 2020 and explored their training behaviors (training
knowledge, beliefs/attitudes, and practices), including specific questions on their training intensity, frequency, and session
duration before and during lockdown (MarchâJune 2020).
RESULTS Overall, 85% of athletes wanted to âmaintain training,â and 79% disagreed with the statement that it is âokay to not
train during lockdown,â with a greater prevalence for both in higher-level athletes. In total, 60% of athletes considered âcoaching
by correspondence (remote coaching)â to be sufficient (highest amongst world-class athletes). During lockdown, < 40%
were able to maintain sport-specific training (e.g., long endurance [39%], interval training [35%], weightlifting [33%], most (83%) training for âgeneral fitness and health maintenanceâ during lockdown. Athletes trained alone (80%) and focused
on bodyweight (65%) and cardiovascular (59%) exercise/training during lockdown. Compared with before lockdown, most
athletes reported reduced training frequency (from between five and seven sessions per week to four or fewer), shorter training
sessions (from â„ 60 to < 60 min), and lower sport-specific intensity (~ 38% reduction), irrespective of athlete classification.
CONCLUSIONS COVID-19-related lockdowns saw marked reductions in athletic training specificity, intensity, frequency, and
duration, with notable within-sample differences (by athlete classification). Higher classification athletes had the strongest
desire to âmaintainâ training and the greatest opposition to ânot trainingâ during lockdowns. These higher classification
athletes retained training specificity to a greater degree than others, probably because of preferential access to limited training
resources. More higher classification athletes considered âcoaching by correspondenceâ as sufficient than did lower
classification athletes. These lockdown-mediated changes in training were not conducive to maintenance or progression of
athletesâ physical capacities and were also likely detrimental to athletesâ mental health. These data can be used by policy
makers, athletes, and their multidisciplinary teams to modulate their practice, with a degree of individualization, in the
current and continued pandemic-related scenario. Furthermore, the data may drive training-related educational resources
for athletes and their multidisciplinary teams. Such upskilling would provide athletes with evidence to inform their training
modifications in response to germane situations (e.g., COVID related, injury, and illness).A specific funding was provided by the National Sports Institute
of Malaysia for this study.The National Sports Institute of Malaysia.https://www.springer.com/journal/40279am2023Sports Medicin
COVID-19 lockdown : a global study investigating athletesâ sport classification and sex on training practices
PURPOSE : To investigate differences in athletesâ knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. METHODS : Athletes (12,526; 66% male; 142 countries) completed an online survey (MayâJuly 2020) assessing knowledge, beliefs, and practices toward training. Sports were classified as team sports (45%), endurance (20%), power/technical (10%), combat (9%), aquatic (6%), recreational (4%), racquet (3%), precision (2%), parasports (1%), and others (1%). Further analysis by sex was performed. RESULTS : During lockdown, athletes practiced body-weight-based exercises routinely (67% females and 64% males), ranging from 50% (precision) to 78% (parasports). More sport-specific technical skills were performed in combat, parasports, and precision (âŒ50%) than other sports (âŒ35%). Most athletes (range: 50% [parasports] to 75% [endurance]) performed cardiorespiratory training (trivial sex differences). Compared to prelockdown, perceived training intensity was reduced by 29% to 41%, depending on sport (largest decline: âŒ38% in team sports, unaffected by sex). Some athletes (range: 7%â49%) maintained their training intensity for strength, endurance, speed, plyometric, change-of-direction, and technical training. Athletes who previously trainedââ„5 sessions per week reduced their volume (range: 18%â28%) during lockdown. The proportion of athletes (81%) trainingââ„60 min/session reduced by 31% to 43% during lockdown. Males and females had comparable moderate levels of training knowledge (56% vs 58%) and beliefs/attitudes (54% vs 56%). CONCLUSIONS : Changes in athletesâ training practices were sport-specific, with few or no sex differences. Team-based sports were generally more susceptible to changes than individual sports. Policy makers should provide athletes with specific training arrangements and educational resources to facilitate remote and/or home-based training during lockdown-type events.https://journals.humankinetics.com/view/journals/ijspp/ijspp-overview.xmlhj2023Sports Medicin
Contribution a l'analyse des systemes stochastiques dont les parametres sont aleatoires
SIGLECNRS T 60054 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Stabilisation par retour d'Ă©tat d'une classe de systĂšmes dynamiques Ă temps discret et Ă retards multiples variant dans le temps
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