171 research outputs found
GROUND REACTION FORCE OF ROTATIONAL SHOT PUT – CASE STUDY
The purpose of this study was to investigate the kinetic variables of two legs during rotational shot put. Three male rotational shot putters served as subjects. Two force platforms were synchronized to collect the data. The kinetic variables of right leg which had the trend of decrease with better performance were the maximal vertical force, rate of force development of maximal propulsive force, impulse of horizontal and vertical force during braking phase, total impulse of horizontal and vertical force. The kinetic variables of left leg which had the trend of increase with better performance were the total impulse of vertical and horizontal force. The smaller braking and greater propulsive time of the right leg, and the greater braking and vertical thrust of the left leg would helpful for better performances
MOMENT AND POWER OF SHOULDER AND ELBOW IN SHOT-PUTTING
The purpose of this study was to quantify the moments and power of the elbow and shoulder joints. Three-dimensional methods and inverse dynamics were used to analyze the throwing arm of shot putter performing standing throws. The proximal to distal sequence was found on moments and power of the elbow and shoulder. The mechanical outputs from elbow and shoulder muscles were mainly energy generation
INFLUENCE OF ARCH SUPPORT INSOLE ON PEOPLE WITH FLATFOOT DURING UPHILL AND DOWNHILL WALKING
The purpose of this study was to investigate the effect of the arch support insole for people with flatfoot during uphill and downhill walking. Sixteen healthy collegiate students with flatfoot were recruited in this study. The heart rate, V02max, and median frequency of surface EMG were recorded and analyzed in this study. Non-parametric Wilcoxon signed-rank test was used for statistics. The derived main results were outlined as follows: (a) V02max had significantly decreased in arch support insole compare to flat foot insole during uphill and downhill walking; (b) arch support insole could reduce the fatigue of rectus femoris muscle during downhill walking which might be associated with the decreased V02max. The integrated research results could effectively be applied to the measurement of muscle fatigue
Purple urine bag syndrome in nursing homes: Ten elderly case reports and a literature review
Purple urine bag syndrome (PUBS) is a rare occurrence, in which the patient has a purple-colored urine bag following urinary catheterization for hours to days. Most of authors believe it is a mixture of indigo (blue) and indirubin (red) that becomes purple. Previous study showed that PUBS occurred predominantly in chronically catheterized, constipated women. We collected 10 elderly patients with PUBS in two nursing homes. The first two cases were identified by chart review in 1987 and 2003, and then later eight cases (42.1%) were collected among 19 urinary catheterized elderly in the period between January 2007 and June 2007. In the present report, PUBS probably can occur in any patients with the right elements, namely urinary tract infection (UTI) with bacteria possessing these enzymes, diet with enough tryptophan, and being catheterized. Associations with bed-bound state, Alzheimer’s, or dementia from other causes are reflections of the state of such patients who are at higher risk for UTI, and hence PUBS occurred. Although we presented PUBS as a harmless problem, prevention and control of the nosocomial catheter-associated UTIs (CAUTIs) has become very important in the new patient-centered medical era. Thus, we should decrease the duration of catheterization, improve catheter care, and deploy technological advances designed for prevention, especially in the elderly cared for in nursing homes
EFFECT OF SHORT MEDIALSIDE STUDS OM FOOT BIOMECHANICS IN COLLEGIATE SOCCER PLAYERS
The purpose of this study was to examine the effect of modified stud on ankle and foot kinematics, ground reaction force and forefoot force and pressure during sidestep cut (SC) and change direction (CD) movement 6 male collegiate soccer players wore original and medial-side 2mm cut stud shoes and performed SC and CD on the artificial grass. Non-parametric Wilcoxon signed-rank test was used to compare difference between the original and modified studs. The modified stud of non-dominant leg show less inversion than the original stud in SC and CD. The modified stud of non-dominant leg show more force peak form and pressure and that of nondominant legs show more pressure an the original stud during SC and CD. The short medial-side studs with 2mm length can decrease the force inversion of the nondmiiant leg during SC and CD movement and increase the force production of the lower extremities in recreational soccer players
Developing the Effective Method of Spectral Harmonic Energy Ratio to Analyze the Arterial Pulse Spectrum
In this article, we analyze the arterial pulse in the spectral domain. A parameter, the spectral harmonic energy ratio (SHER), is developed to assess the features of the overly decreased spectral energy in the fourth to sixth harmonic for palpitation patients. Compared with normal subjects, the statistical results reveal that the mean value of SHER in the patient group (57.7 ± 27.9) is significantly higher than that of the normal group (39.7 ± 20.9) (P-value = .0066 < .01). This means that the total energy in the fourth to sixth harmonic of palpitation patients is significantly less than it is in normal subjects. In other words, the spectral distribution of the arterial pulse gradually decreases for normal subjects while it decreases abruptly in higher-order harmonics (the fourth, fifth and sixth harmonics) for palpitation patients. Hence, SHER is an effective method to distinguish the two groups in the spectral domain. Also, we can thus know that a “gradual decrease” might mean a “balanced” state, whereas an “abrupt decrease” might mean an “unbalanced” state in blood circulation and pulse diagnosis. By SHER, we can determine the ratio of energy distribution in different harmonic bands, and this method gives us a novel viewpoint from which to comprehend and quantify the spectral harmonic distribution of circulation information conveyed by the arterial pulse. These concepts can be further applied to improve the clinical diagnosis not only in Western medicine but also in traditional Chinese medicine (TCM)
An Astigmatic Detection System for Polymeric Cantilever-based Sensors
We demonstrate the use of an astigmatic detection system (ADS) for resonance frequency identification of polymer microcantilever sensors. The ADS technology is based on a DVD optical head combined with an optical microscope (OM). The optical head has a signal bandwidth of 80 MHz, allowing thermal fluctuation measurements on cantilever beams with a subnanometer resolution. Furthermore, an external excitation can intensify the resonance amplitude, enhancing the signal- to-noise ratio. The full width at half maximum (FWHM) of the laser spot is 568 nm, which facilitates read-out on potentially submicrometer-sized cantilevers. The resonant frequency of SU-8 microcantilevers is measured by both thermal fluctuation and excited vibration measurement modes of the ADS
Drastic population fluctuations explain the rapid extinction of the passenger pigeon
To assess the role of human disturbances in species' extinction requires an understanding of the species population history before human impact. The passenger pigeon was once the most abundant bird in the world, with a population size estimated at 3-5 billion in the 1800s; its abrupt extinction in 1914 raises the question of how such an abundant bird could have been driven to extinction in mere decades. Although human exploitation is often blamed, the role of natural population dynamics in the passenger pigeon's extinction remains unexplored. Applying high-throughput sequencing technologies to obtain sequences from most of the genome, we calculated that the passenger pigeon's effective population size throughout the last million years was persistently about 1/10,000 of the 1800's estimated number of individuals, a ratio 1,000-times lower than typically found. This result suggests that the passenger pigeon was not always super abundant but experienced dramatic population fluctuations, resembling those of an "outbreak" species. Ecological niche models supported inference of drastic changes in the extent of its breeding range over the last glacial-interglacial cycle. An estimate of acorn-based carrying capacity during the past 21,000 y showed great year-to-year variations. Based on our results, we hypothesize that ecological conditions that dramatically reduced population size under natural conditions could have interacted with human exploitation in causing the passenger pigeon's rapid demise. Our study illustrates that even species as abundant as the passenger pigeon can be vulnerable to human threats if they are subject to dramatic population fluctuations, and provides a new perspective on the greatest human-caused extinction in recorded history
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