Expert athletes are determined to make faster and better decisions, as revealed in several simple heuristic studies using verbal reports or micro-movement responses. However, heuristic ...decision-making experiments that require motor responses, also being considered as the embodied-choice experiments, are still underrepresented. Furthermore, it is less understood how decision time and confidence depend on the type of embodied choices players make. To scrutinize the decision-making processes (i.e., decision time, decision confidence), this study investigated the embodied choices of male athletes with different expertise in a close-to-real-life environment; 22 elite (
M
age
= 17.59 yrs.,
SD
= 3.67), and 22 amateur (
M
age
= 20.71 yrs.,
SD
= 8.54) team handball players performed a sport-specific embodied-choice test. Attack sequences (
n
= 32) were shown to the players, who had to choose between four provided options by giving a respective sport-specific motor response. We analyzed the frequencies of
specific choices
and the
best choice
, as well as the respective decision time and decision confidence. Elite and amateur players differed in the frequencies of
specific
choices (i.e., forward/tackling; passive blocking), and elite players made the
best choice
more often. Slower decision times of elite players were revealed in
specific choices
and in
best choices
, the confidence of decisions was rated equally high by both player groups. Indications are provided that elite players make better choices rather slower, instead of faster. We suppose this is due to specific sensorimotor interactions and speed-accuracy-tradeoffs in favor of accuracy in elite players. Our findings extend expert decision-making research by using an embodied-choice paradigm, highlighting considerations of decision time and confidence in future experiments.
Physical performance is an essential factor for becoming a top elite team handball player; however, the relationship between specific and general physical performance is not well known. Consequently, ...the aim of the study was (1) to analyze the relationship between specific game-based and general physical performance in young elite male team handball players, and (2) to reduce the number of tests for a more practical implementation of physical performance diagnostics in team handball. Twenty young adult elite male team handball field players (18.6 ± 2.1 years) performed the team handball game-based performance test (GBPT), including specific movements in offense and defense such as catching, passing and throwing a ball, sprinting, stops, changes in direction, jumping, checking and screening, as well as general tests, including a 20 m sprinting test, a repeated sprint ability test (RSA), a modified t-test, countermovement (CMJ), squat (SJ) and drop jump test (DJ), a standing long jump test, a single-leg lateral three jumps test, a standing throw test, and the determination of the one repetition maximum (1RM) in the bench press, bench pull, front squat, and deadlift. Significant correlations were mostly found between different sprinting and jumping tests as well as between different strength tests. The principal component factor analysis revealed four components (power and speed, strength, jump shot performance, and endurance) including 21 variables of high loads (>0.60 or <−0.60). Due to the correlations between the different tests, we suggest a more practicable testing procedure including the 20 m sprinting test, CMJ test, 1RM in the bench press and front squat, as well as the GBPT for elite teams, or the t-test and the YoYo intermittent recovery test for youth and non-elite teams. Despite some correlations between specific and general tests, we suggest using the GBPT to measure specific performance in team handball.
Athletic features distinguishing experts from non-experts in team sports are relevant for performance analyses, talent identification and successful training. In this respect, perceptual-cognitive ...factors like decision making have been proposed to be important predictor of talent but, however, assessing decision making in team sports remains a challenging endeavor. In particular, it is now known that decisions expressed by verbal reports or micro-movements in the laboratory differ from those actually made in on-field situations in play. To address this point, our study compared elite and amateur players' decision-making behavior in a near-game test environment including sport-specific sensorimotor responses. Team-handball players (
= 44) were asked to respond as quickly as possible to representative, temporally occluded attack sequences in a team-handball specific defense environment on a contact plate system. Specifically, participants had to choose and perform the most appropriate out of four prespecified, defense response actions. The frequency of responses and decision time were used as dependent variables representing decision-making behavior. We found that elite players responded significantly more often with offensive responses (
< 0.05, odds ratios: 2.76-3.00) in left-handed attack sequences. Decision time decreased with increasing visual information, but no expertise effect was found. We suppose that expertise-related knowledge and processing of kinematic information led to distinct decision-making behavior between elite and amateur players, evoked in a domain-specific and near-game test setting. Results also indicate that the quality of a decision might be of higher relevance than the required time to decide. Findings illustrate application opportunities in the context of performance analyses and talent identification processes.
In team handball, the individual match performance of each player is essential for winning games; however, a validated match analysis system is still lacking. Consequently, the aim of the study was ...to justify (1) the different relevant variables and their scoring within the individual match analysis (PlayerScore), (2) to determine the intra-rater reliability and validity of the PlayerScore, and (3) to determine the influence of the rater in relation to their degree of expertise level. Six games (three games each of Spain and Brazil, one game twice) of the 2021 World Championship were analyzed by six different raters. The PlayerScore was calculated for each field player of Spain and Brazil in all seven analyzed games. We found a high intra-rater reliability (ICC = 0.97) for the two rated games (Spain against Germany), a highly significant difference (p < 0.001) between the summarized team PlayerScore of Spain and Brazil, as well as significant differences (p < 0.001) for the factor “game” and “rater” (p < 0.05), but no significant interaction for “game × rater” (p = 0.90) in the two-way repeated measures ANOVA. We conclude that the PlayerScore is a reliable and valid rating tool to determine the individual players’ performance in team handball; however, the raters should have sufficient experience in the different techniques and tactics in team handball.
This study contributes to a better understanding of geogenic reef distribution in the southern Baltic Sea and highlights the implications of survey-related factors on automated boulder classification ...when utilizing data from multiple surveys. The distribution of hard grounds and reefs is needed as a baseline for geological and biological studies, but also for offshore construction, navigation and coastal management. In this study we provide maps of the distribution of geogenic reefs for about 750 km
2
in the southern Baltic Sea, at the sites Wismar Bay, Darss Sill and Plantagenet Ground. The maps are based on full-coverage backscatter surveys with different side scan sonar and multibeam echo sounder systems. The distribution and number of boulders in the backscatter maps was determined using a convolutional neural network combined with quality control by human experts. The extent of the geogenic reefs was calculated on the basis of the number of boulders in 50 m x 50 m grid cells. We compare the results with previous reef maps based on point sampling, which show reefs of either biogenic or geogenic origin. According to the earlier maps, 11% of the Plantagenet Ground seabed was classified as reef habitat type. This is similar to the result of our study (12%), although we only considered reefs of geogenic origin. In the Darss Sill, geogenic reefs are larger in this study than in previous maps (30% versus 23%). In both regions, the spatial distribution of reefs differs significantly between old and new maps. For Wismar Bay, previous maps classify 3% of the seafloor as habitat type reef, whereas this study classifies 35% as geogenic reef. The use of automated classification during seafloor mapping allowed large areas to be interpreted in a few days. It also provided more information on the distribution of boulders within the geogenic reef. However, the boulder distribution maps show the negative effects of survey geometry, frequency and environmental conditions on automated boulder classification when data from different surveys are combined.
The temporal occlusion paradigm is often used in anticipation and decision-making research in sports. Although it is considered as a valid measurement tool, evidence of its reproducibility is lacking ...but required for future cross-sectional and repeated-measures designs. Moreover, only a few studies on decision making in real-world environments exist. Here, we aimed at (a) implementing a temporal occlusion test with multi-dimensional motor response characteristics, and (b) assessing intra- and inter-session item reliability. Temporally occluded videos of attack sequences in a team handball scenario were created and combined with the SpeedCourt® contact plate system. Participants were instructed to perform pre-specified defensive actions in response to the video stimuli presented on a life-size projection screen. The intra- and inter-session (after at least 24 h) reproducibility of subjects’ motor responses were analyzed. Significant Cohen’s (0.44–0.54) and Fleiss’ (0.33–0.51) kappa statistics revealed moderate agreement of motor responses with the majority of attack situations in both intra- and inter-session analyses. Participants made faster choices with more visual information about the opponents’ unfolding action. Our findings indicate reliable decisions in a complex, near-game test environment for team handball players. The test provides a foundation for future temporal occlusion studies, including recommendations for new explanatory approaches in cognition research.
Type I phosphatidylinositol 4-phosphate 5-kinase (PIP5K) catalyzes the formation of the phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP2), which is implicated in many cellular processes. The ...Rho GTPases, RhoA and Rac1, have been shown previously to activate PIP5K and to bind PIP5K. Three type I PIP5K isoforms (Iα,Iβ, and Iγ) have been identified; however, it is unclear whether these isoforms are differentially or even sequentially regulated by Rho GTPases. Here we show that RhoA and Rac1, as well as Cdc42, but not the Ras-like GTPases, RalA and Rap1A, markedly stimulate PIP2 synthesis by all three PIP5K isoforms expressed in human embryonic kidney 293 cells, both in vitro and in vivo. RhoA-stimulated PIP2 synthesis by the PIP5K isoforms was mediated by the RhoA effector, Rho-kinase. Stimulation of PIP5K isoforms by Rac1 and Cdc42 was apparently independent of and additive with RhoA- and Rho-kinase, as shown by studies with C3 transferase and Rho-kinase mutants. RhoA, and to a lesser extent Rac1, but not Cdc42, interacted in a nucleotide-independent form with all three PIP5K isoforms. Binding of PIP5K isoforms to GTP-bound, but not GDP-bound, RhoA could be displaced by Rho-kinase, suggesting a direct and constitutive PIP5K-Rho GTPase binding, which, however, does not trigger PIP5K activation. In summary, our findings indicate that synthesis of PIP2 by the three PIP5K isoforms is controlled by RhoA, acting via Rho-kinase, as well as Rac1 and Cdc42, implicating that regulation of PIP2 synthesis has a central position in signaling by these three Rho GTPases.
Combination therapy with terlipressin and albumin substitution is considered a widely accepted treatment regimen for patients with hepatorenal syndrome (HRS). However, only half of the patients ...respond to treatment and to date albumin substitution and terlipressin therapy are among the most expensive medical treatments available for patients with liver diseases. Thus, we aimed to identify clinical and etiological parameters to predict treatment response and overall mortality in patients with HRS.
We retrospectively evaluated 21 patients, 13 male/8 female, aged 43-72 years with HRS. Four patients were transplanted after following combination treatment. Terlipressin was administered by continuous intravenous perfusion (2-6 mg/d) and albumin drips (50 mg) were given daily. Treatment response was defined by a decrease in serum creatinine level to ≤ 1.5 mg/dL or by a ≥ 50% reduction of the baseline concentration.
57% of the patients responded to treatment, which was associated with improved survival at day 60, compared to non-responders. However, the overall mortality was not different between the two groups. Median age of 63 years was a significant negative predictor for therapy response. High baseline urinary sodium levels were of prognostic value for survival. The Model of End stage Liver Disease score (MELD score) did not correlate with therapy response.
In conclusion high age is a predictor of non-response. Low urinary sodium before treatment is associated with poor survival. Terlipressin and albumin co-treatment is associated with increased two-months survival rate. This seemingly moderate extension in survival rate can, however, be decisive for obtaining liver transplantation.
Water conductance of the cuticular membrane (CM) of mature sweet cherry fruit (Prunus avium L. cv. Sam) was investigated by monitoring water loss from segments of the outer pericarp excised from the ...cheek of the fruit. Segments consisted of epidermis, hypodermis and several cell layers of the mesocarp. Segments were mounted in stainless-steel diffusion cells with the mesocarp surface in contact with water, while the outer cuticular surface was exposed to dry silica (22 ± 1 °C). Conductance was calculated by dividing the amount of water transpired per unit area and time by the difference in water vapour concentration across the segment. Conductance values had a log normal distribution with a median of 1.15 × 10-4 m s-1 (n = 357). Transpiration increased linearly with time. Conductance remained constant and was not affected by metabolic inhibitors (1 mM NaN3 or 0.1 mM carbonylcyanide m-chlorophenylhydrazone) or thickness of segments (range 0.8—2.8 mm). Storing fruit (up to 42 d, 1 °C) used as a source of segments had no consistent effect on conductance. Conductance of the CM increased from cheek (1.16 ± 0.10 × 10-4 m s-1) to ventral suture (1.32 ± 0.07 × 10-4 m s-1) and to stylar end (2.53 ± 0.17 × 10-4 m s-1). There was a positive relationship (r2 = 0.066**; n = 108) between conductance and stomatal density. From this relationship the cuticular conductance of a hypothetical astomatous CM was estimated to be 0.97 ± 0.09 × 10-4 m s-1. Removal of epicuticular wax by stripping with cellulose acetate or extracting epicuticular plus cuticular wax by dipping in CHCl3/methanol increased conductance 3.6- and 48.6-fold, respectively. Water fluxes increased with increasing temperature (range 10—39 °C) and energies of activation, calculated for the temperature range from 10 to 30 °C, were 64.8 ± 5.8 and 22.2 ± 5.0 kJ mol-1 for flux and vapour-concentration-based conductance, respectively.
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