Knee movement patterns of injured and uninjured adolescent basketball players when landing from a jump: A case-control study

BACKGROUND: A common knee injury mechanism sustained during basketball is landing badly from a jump. Landing is a complex task and requires good coordination, dynamic muscle control and flexibility. For adolescents whose coordination and motor control has not fully matured, landing badly from a jump can present a significant risk for injury. There is currently limited biomechanical information regarding the lower limb kinetics of adolescents when jumping, specifically regarding jump kinematics comparing injured with uninjured adolescents. This study reports on an investigation of biomechanical differences in landing patterns of uninjured and injured adolescent basketball players. METHODS: A matched case-control study design was employed. Twenty-two basketball players aged 14–16 years participated in the study: eleven previously knee-injured and eleven uninjured players matched with cases for age, gender, weight, height and years of play, and playing for the same club. Six high-speed, three-dimensional Vicon 370 cameras (120 Hz), Vicon biomechanical software and SAS Version 8 software were employed to analyse landing patterns when subjects performed a "jump shot". Linear correlations determined functional relationships between the biomechanical performance of lower limb joints, and paired t-tests determined differences between the normalised peak biomechanical parameters. RESULTS: The average peak vertical ground reaction forces between the cases and controls were similar. The average peak ground reaction forces between the cases and controls were moderately correlated (r = -0.47). The control (uninjured) players had significantly greater hip and knee flexion angles and significantly greater eccentric activity on landing than the uninjured cases (p < 0.01). CONCLUSION: The findings of the study indicate that players with a history of knee injuries had biomechanically compromised landing techniques when compared with uninjured players matched for gender, age and club. Descriptions (norms) of expected levels of knee control, proprioceptive acuity and eccentric strength relative to landing from a jump, at different ages and physical developmental stages, would assist clinicians and coaches to identify players with inappropriate knee performance comparable to their age or developmental stage

Compounds from Silicones Alter Enzyme Activity in Curing Barnacle Glue and Model Enzymes

Background: Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity. Methodology/Principal Findings: GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents. Conclusions/Significance: Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties

2-[7-(3,5-Dibromo-2-hydroxyphenyl)-6-ethoxycarbonyl-2-oxo-5H-2,3,6,7-tetrahydrothiopyrano[2,3-d][1,3]thiazol-6-yl]acetic acid ethanol monosolvate

The title compound, C17H15Br2NO6S2&amp;#183;C2H5OH, is the esterification reaction product of 2-(8,10-dibromo-2,6-dioxo-3,5,5a,11b-tetrahydro-2H,6H-chromeno[4&amp;#8242;,3&amp;#8242;:4,5]thiopyrano[2,3-d]thiazol-5a-yl)acetic acid. Cleavage of the lactone ring and formation of ethoxycarbonyl and hydroxy groups from its structural elements were observed. On the other hand, the carboxymethyl group was not esterified. The H atom and carboxymethyl group, both at stereogenic centres, show a cis conformation. The six-membered dihydrothiopyran ring adopts a half-chair conformation. All NH and OH groups participate in the three-dimensional hydrogen-bond network, which is additionally strengthened by C&amp;#8212;H...O and C&amp;#8212;H...S interactions. Intramolecular O&amp;#8212;H...Br and C&amp;#8212;H...O interactions also occur

Artificial intelligence as an object of civil law regulation

The phrase "artificial intelligence" was first used in 1956, and since then it has raised a lot of questions that still have no answer. In general, artificial intelligence is a system that simulates human behaviour at an elementary level. This is necessary so that the machine performs various tasks, and learns something new in the process of performing. Then the system will use the acquired knowledge to perform even more difficult tasks. This phenomenon is being studied by world scientists, each of whom contributes to the development of artificial intelligence. The article examines two concepts of legal regulation of artificial intelligence – the subject theory and the object theory. The author of the paper gives arguments according to which the development of civil legislation of Ukraine should be carried out according to the vector of perception of artificial intelligence as an object of civil legal relations. The rules for regulating relations on the use of artificial intelligence should be concentrated within the framework of intellectual property law, IT law and consumer legislation

Synthesis of polyesters containing disiloxane subunits: Structural characterization, kinetics, and an examination of the thermal tolerance of Novozym-435

This paper reports the Novozym-435 mediated polymerization of disiloxane-containing polyester monomers under solvent-free conditions. The thermal tolerance of the immobilized enzyme was examined by conducting polymerization cycles over a temperature range of 35-150 °C. Increasing the temperature up to 100 °C afforded an increase in the apparent second order rate constant. Residual activity was measured using the production of octyl palmitate. The enzyme was shown to retain on average greater than 90% of its residual activity regardless of the polymerization temperature. This prompted a study of the long term thermal tolerance of the biocatalyst in which it was determined that over ten reaction cycles there was a significant decrease in the initial polymerization rate, but no change in the degree of monomer conversion after 24 h. The disiloxane containing polyesters were characterized using nuclear magnetic resonance spectroscopy and Fourier-transform infrared spectroscopy. Differential scanning calorimetry was used to determine the thermal properties of the disiloxane-containing polyesters. © 2012 Elsevier B.V. All rights reserved