Bioenergetics and time-motion analysis of competitive basketball

Basketball has been considered to require players to employ extensive amount of energy throughout games. However, research findings regarding bioenergetic traits and demands of actual basketball performance has been considerably limited. The purpose of this study was to describe and assess bioenergetic traits of actual basketball performance in collegiate female and male players by measuring oxygen consumption (V02), heart rate (HR), blood lactate concentration (BLC), as well as rating of perceived exertion (RPE), and performing a time-motion analysis in team scrimmages. Six female and six male collegiate basketball players (20,0 ±1.2 and 20.8 ± 0.9 years old, respectively) were asked to play team basketball scrimmages while wearing portable measurement systems. V 02 and HR were measured by the portable systems during play, and BLC and RPE were measured during alternate resting periods. Additionally, the subject’s performance was videotaped throughout the scrimmage to conduct time-motion analysis. The female and male players demonstrated mean V 02 values of 33.4 ± 3.6 and 37.0 ± 2.4 ml/kg/min, respectively during play; while mean BLC values were 3.2 ± 0.8 and 4.1 ± 1.2 mmol/L, respectively. They spent 34.1 % of play time performing active movements while 56.9 % o f time walking and 9.0 % standing. No significant differences were observed between the females and males in the variables measured (p \u3e 0.05), except that the males expended significantly greater energy through the scrimmages (49.2 %; p \u3c 0.05). V 02max values obtained from a preliminary testing were significantly correlated to V 02 during play (r = 0.673 for all subjects; p \u3c 0.05) and percent of duration for active movements during play (r = 0.936 and 0.962 for the females and males, respectively; p \u3c 0.05). These results suggest that female and male collegiate basketball require extensive utilization of aerobic metabolism during play and enhancement of aerobic capacity may be beneficial to improve the quality of performance in basketball. In conclusion, this study revealed greater oxygen cost playing basketball than previously expected and demonstrated other specific bioenergetic traits of female and male collegiate basketball

Robotic surgery training and performance

Background: To understand the process of skill acquisition in robotic surgery and to allow useful real-time feedback to surgeons and trainees in future generations of robotic surgical systems, robotic surgical skills should be determined with objective variables. The aim of this study was to assess skill acquisition through a training protocol, and to identify variables for the quantification of proficiency. Methods: Seven novice users of the da Vinci Surgical System engaged in 4 weeks of training that involved practicing three bimanual tasks with the system. Seven variables were determined for assessing speed of performance, bimanual coordination, and muscular activation. These values were compared before and after training. Results: Significant improvements were observed through training in five variables. Bimanual coordination showed differences between the surgical tasks used, whereas muscular activation patterns showed better muscle use through training. The subjects also performed the surgical tasks considerably faster within the first two to three training sessions. Conclusions: The study objectively demonstrated that the novice users could learn to perform surgical tasks faster and with more consistency, better bimanual dexterity, and better muscular activity utilization. The variables examined showed great promise as objective indicators of proficiency and skill acquisition in robotic surgery

Summer-restricted migration of green turtles Chelonia mydas to a temperate habitat of the northwest Pacific Ocean

The foraging habitats of green turtles Chelonia mydas range from tropical to temperate areas. Previous studies have generally been biased toward tropical and sub-tropical areas; hence, available data do not accurately describe the species' foraging activity in temperate areas. To reveal seasonal patterns of habitat use in temperate areas, we conducted a by-catch survey, a mark-recapture study, and satellite tracking of green turtles along the Sanriku Coast, a temperate zone in the northwest Pacific Ocean. From July through November of 2005 to 2014, 78 green turtles were captured during a period of relatively high water temperatures (16 to 24°C). Straight carapace length (SCL) ranged from 36.8 to 85.6 cm (average: 49.4 ± 11.4 cm; n = 78), indicating that most of the turtles were juveniles. In the mark-recapture study, 14 of 72 tagged turtles were recaptured 5 to 426 d after release, 12 of which were recaptured south of the release point. Based on satellite tracking data, 3 turtles travelled more than 500 km to reach southern habitats, where water temperature was warmer (13 to 25°C) than along the Sanriku Coast (4 to 22°C). Our results revealed that the Sanriku Coast is a seasonally restricted habitat for juvenile green turtles, which migrate to southern habitats in winter, and that turtles in temperate areas migrated longer than those in tropical and sub-tropical areas. This is the first report of seasonal migration of juvenile green turtles to a temperate habitat in the northern Pacific Ocean.Publisher PDFPeer reviewe

Proof validation and modification by example generation: A classroom-based intervention in secondary school geometry

ArticleProceedings of the 13th International Congress on Mathematical Education (ICME-13). Hamburg, Germany, 2016-7-24/31, ICME. (2016)journal articl

Objective assessment of proficiency with bimanual inanimate tasks in robotic laparoscopy

Purpose: Development of objective criteria and optimum training protocols are priorities for robotic laparoscopy. However, studies that have attempted to objectify learning have been limited due to lack of task complexity and absence of comparisons between experts and novices. Our aim was to address these limitations and assess proficiency in robotic laparoscopy using bimanual inanimate tasks. Materials and Methods: Six experts and 18 novice users of the da Vinci surgical system (Innovative Surgical, Sunnyvale, CA) performed three bimanual surgical manipulations, two of them in opposite directions, for a total of five different test tasks. During each task, elapsed time and kinematics with respect to the instrument tips were measured and a bimanual coordination analysis was conducted to assess the relationship between the simultaneous movements of both arms. Specifically, task completion time, total traveling distance of the instrument tips, and mean absolute relative phase—a variable for the assessment of bimanual coordination—were calculated for each task and compared between groups. Results: The experts showed significantly shorter task completion times for all tasks (p\u3c 0.05). Significantly higher mean absolute relative phase values were observed for the experts in two tasks (p\u3c 0.05). There were no significant differences regarding total travel distance. Conclusion: Expert users of the da Vinci surgical system performed the designed surgical tasks faster and with higher bimanual dexterity than novices. Bimanual coordination analysis and the tasks used in this study show promise for becoming important components of the objective criteria needed to quantify proficiency in robotic laparoscopy

Physiological demands of competitive basketball

The aim of this study was to assess physiological demands of competitive basketball by measuring oxygen consumption (VO2) and other variables during practice games. Each of 12 players (20.4 ± 1.1 years) was monitored in a 20-min practice game, which was conducted in the same way as actual games with the presence of referees and coaches. VO2 was measured by a portable system during the game and blood lactate concentration (LA) was measured in brief breaks. Subjects were also videotaped for time-motion analysis. Female and male players demonstrated respective VO2 of 33.4 ± 4.0 and 36.9 ± 2.6 mL/kg/min and LA of 3.2 ± 0.9 and 4.2 ± 1.3 mmol/L in the practice games (P\u3e0.05). They spent 34.1% of play time running and jumping, 56.8% walking, and 9.0% standing. Pre-obtained VO2max was correlated to VO2 during play (r=0.673) and to percent of duration for running and jumping (r=0.935 and 0.962 for females and males, respectively). This study demonstrated a greater oxygen uptake for competitive basketball than that estimated based on a previous compendium. The correlation between aerobic capacity and activity level suggests the potential benefit of aerobic conditioning in basketball