THE EFFECT OF SELECTED SPORT SURFACES ON VERTICAL LANDING FORCES IN JUMPING

Introduction: The jump for height has received much attention as an important element in many sport activities, but less attention is given to the impact of landing, which may result in injuries due to the large forces involved (Miller, 1976). Therefore, activities that involve landings are potentially more harmful to the joint when there is inefficient absorptive material within the shoes and/or the sport surface. Cavanagh and Lafortune (1980) found that vertical forces, with magnitudes 2.5 times those found in running, were generated when landing from a vertical jump. Nigg, Denoth and Neukomm (1981) reported a force of magnitude 3.5 times the body weight when landing from a vertical jump. Knowing the magnitude of the vertical reaction forces to human beings, when jumping on different sport surfaces, could assist surface manufacturers and shoe designers in producing products that will reduce impact and therefore reduce injuries

THE EFFECT OF SELECTED SPORT SURFACES ON GROUND REACTION FORCES IN WALKING AND RUNNING

Introduction During physical activity, the human body exerts force against its environment. Previous research indicates that the body is exposed to magnitudes of force equaling 2 to 3 times body weight in running (Bates, 1985 & Dickinson, Cook & Leinhardt, 1985) and 1.1 to 1.3 times body weight in walking (Cavanagh, 1980). The magnitude and duration of these forces are a potential source of physical injury. Most biomechanical research in locomotion has examined the role offootwear. However, there is not enough information on the absorption capacity of shoes to determine their safety limit and the ground reaction force is relatively unaffected by footwear changes (Clarke, Frederick & Hamill, 1984)

Serum glucose concentration and lipid profile in racing horses

The aim of the present work was to evaluate serum glucose concentration and lipid profile in racing horses in Iraq. Blood samples were collected from the jugular vein of 92 clinically healthy racing horses (males and females, Arabian and Cross bred), 2-8 years old at Equestrian Club, Baghdad. Investigations included serum measurements of glucose (sg) and lipid profile parameters; total cholesterol (TC), Triglyceride (TG), high density lipoprotein- cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), very low density lipoprotein-cholesterol (VLDL-C) and the atherogenic ratio (LDL-C/HDL-C), in order to register the normal ranges and mean values of these measured parameters in Iraqi healthy racing horses. Results showed that the range and mean values ± standard error of sg were: 33.3 – 6.71 mmol/l and 5.17±0.07 mmol/l, respectively, whereas the TC was 2.07 – 4.22 mmol/l and 3.01±0.05 mmol/l, TG 0.6 – 1.47 mmol/l and 1.06±0.02 mmol/l, HDL-C 0.93 – 2.25 mmol/l and 1.50±0.03 mmol/l, LDL-C 0.10 – 2.12 mmol/l and 0.91±0.04 mmol/l, VLDL-C 0.31 -0.67 mmol/l and 0.55±0.02 mmol/l, respectively and the atherogenic ratio 0.66±0.03. The data present reference values and mean ± SE for sg and lipid profile parameters in healthy racing horses in Baghdad

Silicon Microleaks for Inlets of Mass Spectrometers

Microleaks for inlets of mass spectrometers used to analyze atmospheric gases can be fabricated in silicon wafers by means of photolithography, etching, and other techniques that are commonly used in the manufacture of integrated circuits and microelectromechanical systems. The microleaks serve to limit the flows of the gases into the mass-spectrometer vacuums to specified very small flow rates consistent with the capacities of the spectrometer vacuum pumps. There is a need to be able to precisely tailor the dimensions of each microleak so as to tailor its conductance to a precise low value. (As used here, "conductance" signifies the ratio between the rate of flow in the leak and the pressure drop from the upstream to the downstream end of the leak.) To date, microleaks have been made, variously, of crimped metal tubes, pulled glass tubes, or frits. Crimped-metal and pulled-glass-tube microleaks cannot readily be fabricated repeatably to precise dimensions and are susceptible to clogging with droplets or particles. Frits tend to be differentially chemically reactive with various gas constituents and, hence, to distort the gas mixtures to be analyzed. The present approach involving microfabrication in silicon largely overcomes the disadvantages of the prior approaches

Systems, methods, and apparatus of a low conductance silicon micro-leak for mass spectrometer inlet

Systems, methods and apparatus are provided through which in some embodiments a mass spectrometer micro-leak includes a number of channels fabricated by semiconductor processing tools and that includes a number of inlet holes that provide access to the channels

Systems, Methods, and Apparatus of a Low Conductance Silicon Micro-Leak for Mass Spectrometer Inlet

Systems, methods and apparatus are provided through which in some embodiments a mass spectrometer micro-leak includes a number of channels fabricated by semiconductor processing tools and that includes a number of inlet holes that provide access to the channels

A NEW TAMPER DETECTION ALGORITHM FOR VIDEO

Few years ago, authentication of visual media has regarded as a crucial research area which concerns with the development of methods and tools to determine if the digital media has been forged or not. The detection of video tampering was a concern of many researchers because of its important role in road accident, court events, and other applications. In this manuscript, a new low cost video forgery detection algorithm has been proposed by utilizing the correlation coefficients between the video frames and embedding them as an encrypted data into the first frame of the video stream. Experimental results show the high performance of the proposed algorithm regarding visual quality and robustness due to the ability to detect tampering even in simple and low-effect attacks

Local industrial pollution induces astrocyte cytoskeleton rearrangement in the dice snake brain: GFAP as a biomarker

The present study was designed to evaluate the responsiveness of modulation of glial fibrillary acidic protein (GFAP) content and its fragmentation in the snake brain as a biomarker of local industrial pollution of aquatic ecosystems. Despite GFAP being a well known cytoskeleton marker of astrocytes’ reactivity in the brain of vertebrates, its expression in the snake brain remains insufficiently described. The GFAP expression and its fragmentation were detected using the immunoblot method in the snake brain. ROS level was determined with dichlorofluorescein diacetate fluorescence. The content of the glial fibrillary acidic protein (GFAP) of filament (cytoskeleton) and soluble (cytosol) fractions in the brain of dice snake Natrix tessellata from three ecosystems with different rates of industrial pollution were studied (two polluted and one clean control site). Characteristic increase in GFAP fragmentation was noted for the snakes from both the researched polluted sites. Significant increase in the content of the GFAP cleaved polypeptide fragments induced by industrial pollution exposure was confirmed in the snakes’ brains. Meaningful GFAP fragmentation was determined in snake brain astrocytes as an increase in cleaved fragments of 47–35 kDa molecular weight for both soluble and cytoskeletal GFAP fractions. We found significant abnormality in the ratio of the GFAP soluble fraction to the cytoskeletal one in contaminant-exposed dice snakes. It should testify to significant metabolic disturbance in nerve cells of the dice snakes. Furthermore, growth of reactive oxygen species level as the main cause of oxidative stress was determined in brains of the snakes exposed to environmental toxicity. Thus, astrocyte cytoskeleton disorders are associated with pollutant-induced redox imbalance in the snake brain. Despite the limited data on glial cell biology in the reptilian brain, the observed results prove that snake astrocytes can respond to the environmental toxicity using typical astroglial response. The presented results evidence that monitoring of molecular characteristics of glial cytoskeleton in dice snakes could be used as reliable biomarker of neurotoxicity and adverse effects of industrial pollution. Further studies are required to elucidate the role of astrocyte cytoskeleton in the response against neurotoxic contaminants