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Previous epidemiological studies suggested that patients with osteoarthritis (OA) of the hip might constitute a definable subset of the population with characteristics that predispose them to joint failure. To investigate this possibility a comparative study of somatotype, bone density, disc degeneration, polyarticular joint degeneration, and soft-tissue calcification was carried out in 3 groups of individuals: (1) patients presenting with OA of the hip; (2) patients with acute femoral neck fracture; (3) healthy controls. OA of the hip was rare in patients with femoral neck fracture; conversely, patients with coxarthrosis did not have the low values for bone density seen in the fracture group. There were significant differences in somatotype in the 2 patient groups; 94% of those with OA were endomorphic mesomorphs. Polyarticular OA occurred with the same prevalence in the 2 groups of women, but among males there was a significantly greater involvement of knees and hands in the OA group than in the fracture group. The highest incidence of joint calcification was found in the fracture group and the lowest in the OA group. It was concluded that patients with OA of the hip form a definable subset of the general population. Within this group the appearances of hip OA are determined by 3 interacting factors: mechanical stress, cartilage degeneration, and bone response. [ABSTRACT FROM AUTHOR]

Data in the literature on bone histomorphometry in the baboon are scant. This study provides data from analysis of trabecular bone of the iliac crest of 16 adult male chacma baboons (Papio ursinus) in captivity. Five animals were young adults judging by the presence of growth cartilage in the iliac crest biopsy. Bone volume resembled that in humans, but trabeculae were thinner and more closely spaced. Bone turnover appeared somewhat lower than in humans. Coupling of resorption and formation was excellent as judged by cellular and kinetic variables; erosion surface was an unreliable indicator of ongoing coupling. The similarities between human and baboon trabecular bone make the baboon suited for the study of microstructure and bone turnover of trabecular bone with relevance to humans. [ABSTRACT FROM AUTHOR]

Chromatin structure is a key regulator of DNA transcription, replication and repair 1 . In humans, the TIP60-EP400 complex (TIP60-C) is a 20-subunit assembly that affects chromatin structure through two enzymatic activities: ATP-dependent exchange of histone H2A-H2B for H2A.Z-H2B, and histone acetylation. In yeast, however, these activities are performed by two independent complexes-SWR1 and NuA4, respectively 2,3 . How the activities of the two complexes are merged into one supercomplex in humans, and what this association entails for the structure and mechanism of the proteins and their recruitment to chromatin, are unknown. Here we describe the structure of the endogenous human TIP60-C. We find a three-lobed architecture composed of SWR1-like (SWR1L) and NuA4-like (NuA4L) parts, which associate with a TRRAP activator-binding module. The huge EP400 subunit contains the ATPase motor, traverses the junction between SWR1L and NuA4L twice and constitutes the scaffold of the three-lobed architecture. NuA4L is completely rearranged compared with its yeast counterpart. TRRAP is flexibly tethered to NuA4L-in stark contrast to its robust connection to the completely opposite side of NuA4 in yeast 4-7 . A modelled nucleosome bound to SWR1L, supported by tests of TIP60-C activity, suggests that some aspects of the histone exchange mechanism diverge from what is seen in yeast 8,9 . Furthermore, a fixed actin module (as opposed to the mobile actin subcomplex in SWR1; ref. 8 ), the flexibility of TRRAP and the weak effect of extranucleosomal DNA on exchange activity lead to a different, activator-based mode of enlisting TIP60-C to chromatin., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: France (FR) and New Caledonia (NC) are both French territories, one in Western Europe, the other as part of the Pacific Island Countries and Territories (PICTs). Despite schooling in similar educational systems, FR and NC adolescents develop distinct relationships with physical activity, which is influenced by the geographical-cultural and symbolic structures of their respective societies. This study explored the distribution of physical activity according to geographical culture and opportunity-temporal dimensions., Methods: Participants were randomly selected, with individual (boys vs. girls), spatial (rural vs. urban), and geographical (FR vs. NC) stratifications. Accelerometers GT3X (ActiGraph TM , Pensacola FL, USA) and daily logbooks were used to measure the physical activity intensity and opportunities during the week., Results: A total of 156 participants were included in this study. A significant effect was found in moderate to vigorous physical activity (MVPA) intensity with the geographical-cultural dimension; participants living in FR were more likely to engage in MVPA, especially in five opportunities: school, supervised leisure, home, school breaks, and transport. For both FR and NC adolescents, physical education lessons had the highest MVPA., Conclusion: This study showed that MVPA differed in the same national educational system according to geographical culture. Physical education lessons could catch the challenge of an "opportunity education" (opportunities are defined as temporal invitations to engage in PA) by opening the door to two particular opportunities: supervised leisure and active transport., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Derigny T et al.)

The article compares the trajectories of students' self-reported test-taking effort during a 120 minutes low-stakes large-scale assessment of English comprehension between a paper-and-pencil (PPA) and a computer-based assessment (CBA). Test-taking effort was measured four times during the test. Using a within-subject design, each of the N = 2,676 German ninth-grade students completed half of the test in PPA and half in CBA mode, where the sequence of modes was balanced between students. Overall, students' test-taking effort decreased considerably during the course of the test. On average, effort was lower in CBA than in PPA. While on average, effort was lower in CBA than in PPA, the decline did not vary between both modes during the test. That is, students' self-reported effort was higher if the items were easier (compared to students' abilities). The consequences of these results concerning the further development of CBA tests and large-scale assessments in general are discussed., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

The baculovirus expression vector system (BEVS) is recognized as a powerful platform for producing challenging proteins and multiprotein complexes both in academia and industry. Since a baculovirus was first used to produce heterologous human IFN-β protein in insect cells, the BEVS has continuously been developed and its applications expanded. We have recently established a multigene expression toolbox (HR-bac) composed of a set of engineered bacmids expressing a fluorescent marker to monitor virus propagation and a library of transfer vectors. Unlike platforms that rely on Tn7-medidated transposition for the construction of baculoviruses, HR-bac relies on homologous recombination, which allows to evaluate expression constructs in 2 weeks and is thus perfectly adapted to parallel expression screening. In this chapter, we detail our standard operating procedures for the preparation of the reagents, the construction and evaluation of baculoviruses, and the optimization of protein production for both intracellularly expressed and secreted proteins., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Background/objectives: Physical Literacy (PL) is increasingly recognized as a key element in studies aimed at promoting Physical Activity (PA), but measurement tools for emerging adults and evidence for assessing and using this concept is lacking in a wide range of contexts. We aimed to validate the French version of the Perceived Physical Literacy Instrument (PPLI): a scale for investigating PL in young French adults., Methods: After PL and PA data collection (n = 2,248, age mean  = 19 ± 1.53 yrs), exploratory and confirmatory factor analyses, Cronbach's α and Omega's ω and an Intraclass-Correlation analysis were undertaken. Spearman's rank correlation and the Boruta algorithm were used to investigate the association between PL and PA. Boruta's algorithm examined deeper external validation by analyzing the strength of an overall PL score in explaining PA, compared with separate dimensions of PL and individual characteristics (BMI, sex)., Results: Results showed an acceptable level of reliability (ICC = 0.91), internal validity (α = 0.88; ω = 0.77), and external validity (Rhô >0.18, p  < 0.01). The Boruta algorithm highlighted that the construct of PL is a significant predictor of PA, although not the strongest one which is social and affective dimension., Conclusion: This study provided data on validity and reliability of the first French assessment tool to measure PL constituted by four intertwined dimensions (physical, cognitive, social, affective). At the same time, it provides new evidence of the association between PL and PA., Competing Interests: The authors declare that they have no competing interests., (© 2023 The Society of Chinese Scholars on Exercise Physiology and Fitness. Published by Elsevier (Singapore) Pte Ltd.)

Background/objective: The holistic concept of physical literacy (PL) embraces different person-centered qualities (physical, cognitive, affective/psychological) necessary to lead physically active lifestyles. PL has recently gained increasing attention globally and Europe is no exception. However, scientific endeavors summarizing the current state of PL in Europe are lacking. Therefore, the goal of this study was to comprehensively assess and compare the implementation of PL in research, policy, and practice across the continent., Methods: We assembled a panel of experts representing 25 European countries. Employing a complementary mixed-methods design, the experts first prepared reviews about the current state of PL in their countries (categories: research, practice/policy). The reviews underwent comparative document analysis, ensuring a transnational four-eyes principle. For re-validation purposes, the representatives completed a quantitative survey with questions reflecting the inductive themes from the document analysis., Results: The document analysis resulted in ten disjunct themes (related to "concept", "research", "practice/policy", "future/prospect") and yielded a heterogenous PL situation in Europe. The implementation state was strongly linked to conceptual discussions (e.g., existence of competing approaches), linguistic issues (e.g., translations), and country-specific traditions. Despite growing scholarly attention, PL hesitantly permeates practice and policy in most countries. Nevertheless, the experts largely anticipate increasing popularity of PL for the future., Conclusion: Despite the heterogeneous situation across Europe, the analysis has uncovered similarities among the countries, such as the presence of established yet not identical concepts. Research should intensify academic activities (conceptual-linguistic elaborations, empirical work) before PL may gain further access into practical and political spheres in the long term., Competing Interests: The following authors have an official role within the International Physical Literacy Association (IPLA): Nigel Green (England) is the official chair, Gillian Bartle (Scotland) leads a special interest group, and also Peter Elsborg (Denmark) and Efstathios Christodoulides (Cyprus) are registered ambassadors within the IPLA. Although all authors declare that they have no conflicts of interest relevant to the content of this article, this information should be made transparent within the scope of this article., (© 2022 The Society of Chinese Scholars on Exercise Physiology and Fitness. Published by Elsevier (Singapore) Pte Ltd.)

In clinical practice, there are often discrepancies between the oncological prognosis of gastrointestinal stromal tumors (GIST) and the actual clinical course. This study aimed to check with our collective how reliably the current classifications (Miettinen, Fletcher) predict the prognosis of GIST and to evaluate whether an extension of the classifications by the parameter proliferation activity could make sense. This prospective study enrolled 58 patients who underwent surgery on GIST from 01/2006 to 12/2016. The postoperative course (curation, recurrence, progress) was correlated with the identified risk classification and the proliferative activity. Coincidences with other tumors were strikingly common in patients with GIST (43%). Based on the risk group assignment of GIST, no assessment of the probability of the occurrence of second neoplasia could be derived. Individual patients were under- or over-graduated concerning the assessment of biological behavior based on the standard risk classifications. The inclusion of proliferative activity did not allow for a more precise predictive power - neither to the risk of recurrence and metastasis nor to the development of a second neoplasia. The study showed that there is currently no parameter or logarithm that reliably predicts the biological behavior of GIST. Due to the frequency of coincidence of second neoplasia and (rare) distant metastases, for everyday clinical practice, appropriate staging diagnostic and regular follow-up care should also be used for benign GIST., Competing Interests: All authors completed the ICMJE uniform disclosure form. The authors have no conflicts of interest to declare., (©2022 JOURNAL of MEDICINE and LIFE.)

Background: Following an ecological framework, the aim of this study was to highlight the way adolescents invested their time in opportunities to engage in moderate to vigorous physical activity (MVPA) according to whether they were profiled as more or less active. This study's innovation lies in the analysis of MVPA according to social occasions which are understood as opportunities to be active throughout the day (e.g. home, school, transport)., Methods: PA data measured by accelerometry (ActiGraph GT3X) for seven consecutive days were compiled, with adolescents' social occasions during the week recorded in a daily digital diary (n = 135). The opportunity ratio of MVPA at each social time is the ratio between time spent in MVPA and the duration of a corresponding social occasion. Following the literature, participants were categorised into three profiles according to their reported amount of MVPA: HEPA active, minimally active and inactive. Non-parametric Wilcoxon signed rank and Kruskal Wallis tests were performed to determine the relative intensity of PA performed at different social occasions, and to investigate whether intensities differed between adolescents with various activity profiles., Results: Results showed that engagement in MVPA at different social occasions differed according to participant profiles. Mismatch was noticed between the opportunity ratio and the duration of the most and least favorable social occasions for MVPA. For all three profiles, the social occasion "physical education lesson" revealed an opportunity ratio of MVPA (23.6% vs 17.0% vs 13.8%) significantly higher than the overall opportunity ratio of the week (6.9% vs 2.9% vs 1.2%), but of lower duration. Conversely, "home" (5.3% vs 0.0% vs 0.0%) and "school" (outside of PE time) (2.4% vs 0.0% vs 0.0%) represented the two least opportune social occasions for PA in an adolescent's week., Conclusions: Rethinking engagement with MVPA in the context of temporal opportunities would allow potential ways to intervene within an educational supervised setting to help young people adopt a physically active lifestyle at the end of the key period of adolescence. These results reinforced the importance of context in interventions for PA promotion, opening for "time education" in people., (© 2022. The Author(s).)

Children between the ages of 4-6 years represent the population most affected by drowning accidents, while their early involvement in physical activity, and more specifically in aquatic activities is a key factor in their future physical life journey. The systematic review's purpose was to identify aspects in the intervention's studies with children and/or their parents that had a significant impact on the Aquatic Literacy (AL) dimensions mentioned as motor, psychological, affective, and cognitive. The PICO method was used to define the research question and PRISMA checklist searched for articles in nine databases: Cochrane, Embase, ERIC, ProQuest, PsychInfo, PubMed, Scopus, SportDiscus, and Web of Science. Eligibility criteria were: (1) English language, (2) primary research, (3) population of 4-6 year old children or their parents, (4) intervention study design, and (5) results related to at least one of the AL domains. The strength of evidence and the risk of bias were assessed. Results showed relatively poor number of studies for such a vulnerable population regarding the drowning risk ( n = 8 for parents and n = 14 for children intervention). Studies did not show a consensus on which educational approach was more beneficial than others. Concerning parental education, results were rather homogeneous, especially concerning the theoretical frameworks employed and the relevancy to include parents in swimming programs. The development of pedagogical tools for promotion and evaluation, based on the AL theoretical framework, could help to clarify the question of "how to teach" children to prevent drowning and engage young children in long-term physical activities.

Pathogen-induced cancers account for 15% of human tumors and are a growing concern for endangered wildlife. Fibropapillomatosis is an expanding virally and environmentally co-induced sea turtle tumor epizootic. Chelonid herpesvirus 5 (ChHV5) is implicated as a causative virus, but its transmission method and specific role in oncogenesis and progression is unclear. We applied environmental (e)DNA-based viral monitoring to assess viral shedding as a direct means of transmission, and the relationship between tumor burden, surgical resection and ChHV5 shedding. To elucidate the abundance and transcriptional status of ChHV5 across early, established, regrowth and internal tumors we conducted genomics and transcriptomics. We determined that ChHV5 is shed into the water column, representing a likely transmission route, and revealed novel temporal shedding dynamics and tumor burden correlations. ChHV5 was more abundant in the water column than in marine leeches. We also revealed that ChHV5 is latent in fibropapillomatosis, including early stage, regrowth and internal tumors; higher viral transcription is not indicative of poor patient outcome, and high ChHV5 loads predominantly arise from latent virus. These results expand our knowledge of the cellular and shedding dynamics of ChHV5 and can provide insights into temporal transmission dynamics and viral oncogenesis not readily investigable in tumors of terrestrial species.

The objectives of this study were to identify how spatiotemporal, kinetic, and kinematic parameters could (i) characterize swimmers' adaptability to different swimming speeds and (ii) discriminate expertise level among swimmers. Twenty male participants, grouped into (a) low-, (b) medium-, and (c) high-expertise levels, swam at four different swim paces of 70, 80, 90% (for 20 s), and 100% (for 10 s) of their maximal speed in a swimming flume. We hypothesized that (i) to swim faster, swimmers increase both propulsion time and the overall force impulse during a swimming cycle; (ii) in the frequency domain, expert swimmers are able to maintain the relative contribution of the main harmonics to the overall force spectrum. We used three underwater video cameras to derive stroking parameters [stroke rate (SR), stroke length (SL), stroke index (SI)]. Force sensors placed on the hands were used to compute kinetic parameters, in conjunction with video data. Parametric statistics examined speed and expertise effects. Results showed that swimmers shared similarities across expertise levels to increase swim speed: SR, the percentage of time devoted to propulsion within a cycle, and the index of coordination (IdC) increased significantly. In contrast, the force impulse ( I + ) generated by the hand during propulsion remained constant. Only the high-expertise group showed modification in the spectral content of its force distribution at high SR. Examination of stroking parameters showed that only high-expertise swimmers exhibited higher values of both SL and SI and that the low- and high-expertise groups exhibited similar IdC and even higher magnitude in I + . In conclusion, all swimmers exhibit adaptable behavior to change swim pace when required. However, high-skilled swimming is characterized by broader functional adaptation in force parameters., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Schnitzler, Seifert and Button.)

Sea turtle populations are under threat from an epizootic tumor disease (animal epidemic) known as fibropapillomatosis. Fibropapillomatosis continues to spread geographically, with prevalence of the disease also growing at many longer-affected sites globally. However, we do not yet understand the precise environmental, mutational and viral events driving fibropapillomatosis tumor formation and progression.Here we perform transcriptomic and immunohistochemical profiling of five fibropapillomatosis tumor types: external new, established and postsurgical regrowth tumors, and internal lung and kidney tumors. We reveal that internal tumors are molecularly distinct from the more common external tumors. However, they have a small number of conserved potentially therapeutically targetable molecular vulnerabilities in common, such as the MAPK, Wnt, TGFβ and TNF oncogenic signaling pathways. These conserved oncogenic drivers recapitulate remarkably well the core pan-cancer drivers responsible for human cancers. Fibropapillomatosis has been considered benign, but metastatic-related transcriptional signatures are strongly activated in kidney and established external tumors. Tumors in turtles with poor outcomes (died/euthanized) have genes associated with apoptosis and immune function suppressed, with these genes providing putative predictive biomarkers.Together, these results offer an improved understanding of fibropapillomatosis tumorigenesis and provide insights into the origins, inter-tumor relationships, and therapeutic treatment for this wildlife epizootic.

Background: Physicians' financial interests might conflict with the best service to patients. It is essential to gain a thorough understanding of the effect of remuneration systems on physician behaviour., Methods: We conducted a controlled laboratory experiment using a within-subject design to investigate physician behaviour underpayment heterogeneity. Each physician provided medical care to patients whose treatments were paid for under fee-for-service (FFS) or capitation (CAP)., Results: We observed that physicians customized their care in response to the payment system. FFS patients received considerably more medical care than did CAP patients with the same illness and treatment preference. Physicians over-served FFS patients and under-served CAP patients. After a CAP payment reduction, we observed neither a quantity reduction under CAP nor a spillover in FFS patients' treatment., Conclusions: The results suggest that, in our experimental model, fee regulation can be used to some extent to control physician spending since we did not identify a behavioural response to the CAP payment cut. Physicians did not recoup lost income by altering treatment behaviour toward CAP and/or FFS patients. Experimental economics is an excellent tool for ensuring the welfare of all those involved in the health system. Further research should investigate payment incentives as a means of developing health care teams that are more efficient.

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player's involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility. This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.

The radical embodied cognition approach to behavior requires emphasis upon how humans adapt their motor skills in response to changes in constraint. The aim of this exploratory study was to identify how the typical coordination patterns used to tread water were influenced by constraints representative of open water environments. Twenty-three participants were measured while treading water (TW) in a swimming flume in four conditions: (1) in still water, wearing a bathing suit (baseline); (2) wearing typical outdoor clothing (clothed); (3) with an additional cognitive task imposed (dual task); and (4) against a changing current (flow). Mixed methods kinematic analysis revealed four different TW coordination patterns were used across the conditions. The four TW patterns used represent a hierarchy of expertise in terms of the capacity to generate continuous lift forces, where pattern 1 (the lowest skill level) involved predominantly pushing and kicking limb movements ( N = 1); pattern 2 was a movement pattern consisting of legs pushing/kicking and arms sculling ( N = 7); pattern 3 was synchronous sculling of all four limbs ( N = 6); and pattern 4 was the "eggbeater kick" (the highest skill level), with asynchronous sculling movements of the legs ( N = 9). The four TW patterns were generally robust to the modified constraints. The higher skilled patterns (i.e., patterns 3 and 4) appeared to be the most stable coordination patterns. These results suggest that learning to perform more complex patterns to tread water might be an asset to survive in life-threatening situations., (Copyright © 2019 Button, Brouwer, Schnitzler and de Poel.)

Wildlife populations are under intense anthropogenic pressures, with the geographic range of many species shrinking, dramatic reductions in population numbers and undisturbed habitats, and biodiversity loss. It is postulated that we are in the midst of a sixth (Anthropocene) mass extinction event, the first to be induced by human activity. Further, threatening vulnerable species is the increased rate of emerging diseases, another consequence of anthropogenic activities. Innovative approaches are required to help maintain healthy populations until the chronic underlying causes of these issues can be addressed. Fibropapillomatosis in sea turtles is one such wildlife disease. Here, we applied precision-medicine-based approaches to profile fibropapillomatosis tumors to better understand their biology, identify novel therapeutics, and gain insights into viral and environmental triggers for fibropapillomatosis. We show that fibropapillomatosis tumors share genetic vulnerabilities with human cancer types, revealing that they are amenable to treatment with human anti-cancer therapeutics., Competing Interests: The authors declare no competing interests.

This study proposes a new qualitative typology that can be used to classify learners treading water into different skill-based categories. To establish the typology, 38 participants were videotaped while treading water and their movement patterns were qualitatively analyzed by two experienced biomechanists. 13 sport science students were then asked to classify eight of the original participants after watching a brief tutorial video about how to use the typology. To examine intra-rater consistency, each participant was presented in a random order three times. Generalizability (G) and Decision (D) studies were performed to estimate the importance variance due to rater, occasion, video and the interactions between them, and to determine the reliability of the raters' answers. A typology of five general classes of coordination was defined amongst the original 38 participants. The G-study showed an accurate and reliable assessment of different pattern type, with a percentage of correct classification of 80.1%, an overall Fleiss' Kappa coefficient K = 0.6, and an overall generalizability φ coefficient of 0.99. This study showed that the new typology proposed to characterize the behaviour of individuals treading water was both accurate and highly reliable. Movement pattern classification using the typology might help practitioners distinguish between different skill-based behaviours and potentially guide instruction of key aquatic survival skills. Key pointsTreading water behavioral adaptation can be classified along two dimensions: the type of force created (drag vs lift), and the frequency of the force impulsesBased on these concepts, 9 behavioral types can be identified, providing the basis for a typologyProvided with macroscopic descriptors (movements of the limb relative to the water, and synchronous vs asynchronous movements), analysts can characterize behavioral type accurately and reliably.

This study examines the relationships between the index of coordination (IdC) and active drag (D) assuming that at constant average speed, average drag equals average propulsion. The relationship between IdC and propulsive efficiency (ep) was also investigated at maximal speed. Twenty national swimmers completed two incremental speed tests swimming front crawl with arms only in free condition and using a measurement of active drag system. Each test was composed of eight 25-m bouts from 60% to 100% of maximal intensity whereby each lap was swum at constant speed. Different regression models were tested to analyse IdC-D relationship. Correlation between IdC and ep was calculated. IdC was linked to D by linear regression (IdC=0.246·D-27.06; R(2)=0.88, P<.05); swimmers switched from catch-up to superposition coordination mode at a speed of ∼1.55ms(-1) where average D is ∼110N. No correlation between IdC and ep at maximal speed was found. The intra-individual analysis revealed that coordination plays an important role in scaling propulsive forces with higher speed levels such that these are adapted to aquatic resistance. Inter-individual analysis showed that high IdC did not relate to a high ep suggesting an individual optimization of force and power generation is at play to reach high speeds., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The increasing fragmentation of forest habitats and the omnipresence of cultivars potentially threaten the genetic integrity of the European wild apple (Malus sylvestris (L.) Mill). However, the conservation status of this species remains unclear in Europe, other than in Belgium and the Czech Republic, where it has been declared an endangered species. The population density of M. sylvestris is higher in the forests of the upper Rhine Valley (France) than in most European forests, with an unbalanced age-structure, an overrepresentation of adults and a tendency to clump. We characterize here the ecology, age-structure and genetic diversity of wild apple populations in the Rhine Valley. We use these data to highlight links to the history of this species and to propose guidelines for future conservation strategies. In total, 255 individual wild apple trees from six forest stands (five floodplain forests and one forest growing in drier conditions) were analysed in the field, collected and genotyped on the basis of data for 15 microsatellite markers. Genetic analyses showed no escaped cultivars and few hybrids with the cultivated apple. Excluding the hybrids, the genetically "pure" populations displayed high levels of genetic diversity and a weak population structure. Age-structure and ecology studies of wild apple populations identified four categories that were not randomly distributed across the forests, reflecting the history of the Rhine forest over the last century. The Rhine wild apple populations, with their ecological strategies, high genetic diversity, and weak traces of crop-to-wild gene flow associated with the history of these floodplain forests, constitute candidate populations for inclusion in future conservation programmes for European wild apple.

The effect of three months of aerobic training on spatio-temporal and coordination parameters was examined during a swim trial at maximal aerobic speed. Nine male swimmers swam a 400-m front crawl at maximal speed twice: in trial 1, after summer break, and trial 2, after three months of aerobic training. Video analysis determined the stroke (swimming speed, stroke length, and stroke rate) and coordination (Index of Coordination and propulsive phase duration) parameters for every 50-m segment. All swimmers significantly increased their swimming speed after training. For all swimmers except one, stroke length increased and stroke rate remained constant, whereas the Index of Coordination and the propulsive phase duration decreased (p<.05). This study suggests that aerobic training developed a greater force impulse in the swimmers during the propulsive phases, which allowed them to take advantage of longer non-propulsive phases. In this case, catch-up coordination, if associated with greater stroke length, can be an efficient coordination mode that reflects optimal drag/propulsion adaptation. This finding thus provides new insight into swimmers' adaptations to the middle-distance event., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A classification system of treading water based on a conceptual typology was first established and then verified empirically. The typology was established on two concepts: the nature of the forces created within the water and the type of inter-limb coordination used. Thirty-eight participants were videotaped while treading water. Multivariate statistics were used to understand how the different behavioural types related to expertise. Three distinct groups of coordination patterns were adopted during treading water. A support vector machine procedure was used as a confirmatory procedure. The data mining process provides a methodological framework to analyse expertise in sports activities, and in this context suggests that a taxonomy can be established among the numerous coordination solutions that allow humans to create stabilising forces in the water.

The effect of (a) increasing velocity and (b) added resistance was examined on the stroke (stroke length, stroke rate [SR]), coordination (index of coordination [IdC], propulsive phases), and force (impulse and peaks) parameters of 7 national-level front crawl swimmers (17.14 ± 2.73 years of swimming; 57.67 ± 1.62 seconds in the 100-m freestyle). The additional resistance was provided by a specially designed parachute. Parachute swimming (PA) and free-swimming (F) conditions were compared at 5 velocities per condition. Video footage was used to calculate the stroke and coordination parameters, and sensors allowed the determination of force parameters. The results showed that (a) an increase in velocity (V) led to increases in SR, IdC, propulsive phase duration, and peak propulsive force (p < 0.05), but no significant change in force impulse per cycle, whatever the condition (PA or F); and (b) in PA conditions, significant increases in the IdC, propulsive phase duration, and force impulse and a decrease in SR were recorded at high velocities (p < 0.05). These results indicated that, in the F condition, swimmers adapted to the change in velocity by modifying stroke and coordination rather than force parameters, whereas the PA condition enhanced the continuity of propulsive action and force development. Added resistance, that is, "parachute training," can be used for specific strength training purposes as long as swimming is performed near maximum velocity.

The purpose of this study was to determine whether the Index of Coordination (IdC) and the propulsive phase durations can differentiate performance level during a maximal 400-m front crawl swim trial. Sixteen male swimmers constituted two groups based on performance level (G1: experts; G2: recreational). All participants swam the 400-m front crawl at maximal speed. Video analysis determined the stroke (swimming speed, stroke length, stroke rate) and coordination (IdC) parameters for every 50 m. Both stroke and coordination parameters discriminated performance level. The expert group had significantly higher values for speed and stroke length and lower values for the relative propulsive phase duration and IdC (p < .05). However there was no significant change in coordination parameters for either group throughout the trial. This suggests that, when associated with greater stroke length, catch-up coordination can be an efficient coordination mode that reflects optimal drag/propulsion adaptation. This finding provides new insight into swimmers' adaptations in a middle-distance event.

The accuracy of a simple field test, the 3-minute, 30-second endurance capacity test (3'30'' ECT), was evaluated in 12 moderately trained athletes. It consisted of 10 3-minute running bouts, separated by 30-second passive recoveries. The first 5 bouts were performed at 75% of maximal aerobic speed (MAS, which was previously determined), and the last 5 were at a self-selected speed. The result of this test is a speed called Vend, expressed in km.h and calculated as the mean speed for the last 5 bouts. The critical velocity (CV) and the individual anaerobic threshold (IAT) were also determined. Another 17 moderately trained athletes then participated in a test-retest procedure to assess the reproducibility of the 3'30'' ECT. The results showed that Vend was correlated with all studied parameters (p < 0.05). Vend and CV did not differ relative to MAS (Vend: 82.8 +/- 3.3% of MAS; CV 82.5 +/- 3.3% of MAS; p > 0.05). The test-retest procedure indicated a coefficient of variation of 1.99 +/- 1.88%. Vend is thus an interesting indicator because (a) it is based on a noninvasive single-visit protocol, (b) its application is in the heavy exercise domain, and (c) it is highly reproducible. The 3'30'' ECT thus seems to be an adequate test to determine endurance capacity in moderately trained subjects.

This study examined the variability of physiological, perceptual, stroke and coordination parameters in both genders during several swim trials at the 400-m pace speed. Twelve national level competitors (6 men, 6 women) swam 400-m at maximal speed. They then swam three additional trials (100, 200 and 300-m) at the pace (speed) of the previous 400-m. Three cameras were used to determine stroke cycle [speed (V), stroke length (SL), stroke rate (SR)] and coordination [index of coordination (IdC), stroke phases] parameters. Physiological [heart rate (HR) and lactate [La-] and perceptual [subjective workload (TWL)] parameters were assessed after each swim trial. Inter-trial data indicated that HR, [La-] and TWL increased significantly with the distance swum (p < 0.05). Inter-trial comparison did not show significant variation of stroke cycle and coordination parameters. Inter-lap data were examined within the 400-m and showed that V and SL decreased significantly at the beginning of the trial (p < 0.05), but IdC and SR remained unchanged (p > 0.05). Thus, despite changes in both physiological and perceptual responses consecutive to increasing fatigue, coordination parameters remained stable during an all-out 400-m freestyle swim. The examination of these parameters based on short-distance trials appears then to be valid, which offers interesting perspectives for swim testing. Key points"During a maximal 400-m, fatigue led to an increase in both physiological (heart rate and blood lactate) and perceptual (subjective workload) parameters.The consequence was a decrease in stroke length and therefore in the swimming speed.However, inter-arm coordination did not change during this aerobic task.This indicates that inter-arm coordination can be examined on the basis of short-distance trials rather than on the full distance.