2,574 research outputs found
Intra-Individual Variability For Basketball Free Throws
Several studies have attempted to identify differences between subjects in the performance of basketball free throws. All of these studies have been twodimensional analyses of free throw kinematics and have analyzed only interindividual variability. An analysis of the directional errors for 1042 free throws completed by NCAA Division I varsity basketball players has revealed that 32.8% of missed free throws were off-line to the left, and 19.5% were off to the right. This is indicative of movement outside the sagittal plane. To date, a three-dimensional analysis of free throw shooting has not been reported in the literature, however. Also, since performers do not execute athletic movements in an identical manner each time, intra-individual variability is a component of athletic performance that should be considered.
The purpose of this study was to complete a three-dimensional kinematic analysis of the intraindividual variability in basketball free throws. The subjects were members of an NCAA Division I varsity basketball team who attempted a minimum of 30 free throws in games over the course of a season.
Five players met this criterion. A total of 648 free throws (FT) were videotaped during games (317 FT) and regular team practices (331 FT) throughout the season. The result of each free throw was classified into one of nine categories--swish, short make, long make, left make, right make, short miss, long miss, left miss, or right miss. A representative sample of free throws was selected that approximated each player's overall performance both in accuracy and error tendency. The number of free throws varied from 10 to 14 for each player. The free throw percentage for the 60 free throws analyzed was 73.3%, compared to an accuracy rate of 73.6% for the 648 free throws recorded. The subjects' free throw percentages ranged from 56.5% to 83.8%. Kinematic variables included range of motion at the wrist, elbow, shoulder, hip, knee, and ankle joints, trunk rotation, arm horizontal abduction/adduction, foot elevation angle, release height, velocity, and angle, and vertical and horizontal center of gravity position. Mean values for kinematic parameters were used to compare inter-individual variability.
Intra-individual variability was defined as ± 1 standard deviation from the mean for each subject. Results indicate that intraindividual variability was larger than inter-individual variability for wrist and elbow ROM, and release velocity. Inter-individual variability was greater than intra-individual variability for hip, knee, and ankle ROM. The intra- and inter-individual differences were comparable for other variables. The findings suggest that multiple samples may be required to ensure representative data
An epidemiological study of burglary offenders: trends and predictors of self-reported arrests for burglary in the United States, 2002-2013
Burglary is serious property crime with a relatively high incidence and has been shown to be variously associated with other forms of criminal behavior. Unfortunately, an epidemiological understanding of burglary and its correlates is largely missing from the literature. Using public-use data collected between 2002 and 2013 as part of the National Survey on Drug Use and Health (NSDUH), the current study compared those who self-reported burglary arrest in the prior 12 months with and without criminal history. The unadjusted prevalence estimates of self-reported burglary arrest were statistically different for those with a prior arrest history (4.7%) compared with those without an arrest history (0.02%) which is a 235-fold difference. Those with an arrest history were more likely to report lower educational attainment, to have lower income, to have moved more than 3 times in the past 5 years, and to use alcohol, tobacco, illicit drugs, and engage in binge drinking. Moreover, those with prior arrest histories were younger and more likely to be male. There is considerable heterogeneity among burglars with criminal history indicating substantially greater behavioral risk
Cavitation-induced ignition of cryogenic hydrogen-oxygen fluids
The Challenger disaster and purposeful experiments with liquid hydrogen (H2)
and oxygen (Ox) tanks demonstrated that cryogenic H2/Ox fluids always
self-ignite in the process of their mixing. Here we propose a
cavitation-induced self-ignition mechanism that may be realized under these
conditions. In one possible scenario, self-ignition is caused by the strong
shock waves generated by the collapse of pure Ox vapor bubble near the surface
of the Ox liquid that may initiate detonation of the gaseous H2/Ox mixture
adjacent to the gas-liquid interface. This effect is further enhanced by H2/Ox
combustion inside the collapsing bubble in the presence of admixed H2 gas
Reduced Apaf-1 levels in cardiomyocytes engage strict regulation of apoptosis by endogenous XIAP
Overexpression studies have identified X-linked inhibitor of apoptosis protein (XIAP) as a potent inhibitor of caspases. However, the exact function of endogenous XIAP in regulating mammalian apoptosis is less clear. Endogenous XIAP strictly regulates cytochrome c–dependent caspase activation in sympathetic neurons but not in many mitotic cells. We report that postmitotic cardiomyocytes, unlike fibroblasts, are remarkably resistant to cytosolic microinjection of cytochrome c. The cardiomyocyte resistance to cytochrome c is mediated by endogenous XIAP, as XIAP-deficient cardiomyocytes die rapidly with cytosolic cytochrome c alone. Importantly, we found that cardiomyocytes, like neurons, have markedly reduced Apaf-1 levels and that this decrease in Apaf-1 is directly linked to the tight regulation of caspase activation by XIAP. These data identify an important function of XIAP in cardiomyocytes and point to a striking similarity in the regulation of apoptosis in postmitotic cells
Design, analysis and test verification of advanced encapsulation systems, phase 2 program results
Optical, electrical isolation, thermal structural, structural deflection, and thermal tests are reported. The utility of the optical, series capacitance, and structural deflection models was verified
Convergent and discriminant validities of SCBE-30 questionnaire using correlated trait–correlated method Minus One
Correlated trait–correlated method minus one was used to evaluate convergent and discriminant validity of Social Competence Behavior Evaluation questionnaire (Social Competence, Anger-Aggression, Anxiety-Withdrawal) between multiple raters. A total of 369 children (173 boys and 196 girls; Mage = 55.85, SDage = 11.54) were rated by their mothers, fathers, and teachers. Results showed more convergence between parents than parent-teacher ratings. Mother-teacher share a common view of child behavior that is not shared with father. Parents had more difficulty distinguishing internalizing and externalizing behaviors (especially fathers). Measurement invariance across child sex was explored, results imply that differences between boys and girls were not due to measure. Girls (compare to boys) were described as more social competent by their fathers and teachers, while boys as more aggressive by mothers and teachers.info:eu-repo/semantics/publishedVersio
Early father-child and mother-child attachment relationships: contributions to preschoolers’ social competence
The main goal of this study was to explore the contributions of early father-child and mother-child attachment relationships to children’s later social competence with their preschool peers; possible unique and shared contributions were tested. Using a multi-method design and focusing on direct observation, attachment was assessed at home at age 3 with the Attachment Behavior Q-sort (AQS) and two years later social competence was assessed at classrooms of 5-year-olds using a set of seven measurement indicators that are part of the Hierarchical Model of Social Competence. Results show that attachment to each parent made unique and significant contributions to children’s social competence and suggested the possibility that each caregiver may have somewhat different patterns of influence on the different indicators of children’s social competence. Findings also suggest the possibility that a secure attachment with one parent may buffer the impact of having an insecure relationship with the other. Due to sample size these results should be seen as a starting point to generate new and larger studies.info:eu-repo/semantics/acceptedVersio
Status of the Standard Solar Model Prediction of Solar Neutrino Fluxes
The Standard Solar Model (BP04) predicts a total 8B neutrino flux that is
17.2% larger than measured in the salt phase of the SNO detector (and if it
were significant it will indicate oscillation to sterile neutrinos). Hence it
is important to examine in details uncertainties (and values) of inputs to the
SSM. Currently, the largest fractional uncertainty is due to the new evaluation
of the surface composition of the sun. We examine the nuclear input on the
formation of solar 8B [S17(0)] and demonstrate that it is still quite uncertain
due to ill known slope of the measured astrophysical cross section factor and
thus ill defined extrapolation to zero energy. This yields an additional
reasonably estimated uncertainty due to extrapolation of +0.0 -3.0 eV-b (+0%
-14%). Since a large discrepancy exists among measured as well as among
predicted slopes, the value of S17(0) is dependent on the choice of data and
theory used to extrapolate S17(0). This situation must be alleviated by new
measurement(s). The "world average" is driven by the Seattle result due to the
very small quoted uncertainty, which we however demonstrate it to be an
over-estimated accuracy. We propose more realistic error bars for the Seattle
results based on the published Seattle data.Comment: Fifth International Conferenceon Non-Accelerator New Physics, Dubna,
June 20-25, 2005. Work Supported by USDOE Grant No. DE-FG02-94ER4087
Inhibition of 5-aminoimidazole-4-carboxamide ribotide transformylase, adenosine deaminase and 5′-adenylate deaminase by polyglutamates of methotrexate and oxidized folates and by 5-aminoimidazole-4-carboxamide riboside and ribotide
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