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1.
Sports Med ; 31(1): 61-73, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11219502

RESUMO

The popularity of fast pitch softball in the US and throughout the world is well documented. Along with this popularity, there has been a concomitant increase in the number of injuries. Nearly 52% of cases qualify as major disabling injuries requiring 3 weeks or more of treatment and 2% require surgery. Interestingly, 75% of injuries occur during away games and approximately 31% of traumas occur during nonpositional and conditioning drills. Injuries range from contusions and tendinitis to ligamentous disorders and fractures. Although head and neck traumas account for 4 to 12% of cases, upper extremity traumas account for 23 to 47% of all injuries and up to 19% of cases involve the knee. Approximately 34 to 42% of injuries occur when the athlete collides with another individual or object. Other factors involved include the quality of playing surface, athlete's age and experience level, and the excessive physical demands associated with the sport. Nearly 24% of injuries involve base running and are due to poor judgement, sliding technique, current stationary base design, unorthodox joint and extremity position during ground impact and catching of cleats. The increasing prevalence of overtraining syndrome among athletes has been attributed to an unclear definition of an optimal training zone, poor communication between player and coach, and the limited ability of bone and connective tissue to quickly respond to match the demands of the sport. This has led routinely to arm, shoulder and lumbar instability, chronic nonsteroidal anti-inflammatory drug (NSAID) use and time loss injuries in 45% of pitching staff during a single season. Specific attention to a safer playing environment, coaching and player education, and sport-specific training and conditioning would reduce the risk, rate and severity of fast pitch traumas. Padding of walls, backstops, rails and dugout areas, as well as minimising use of indoor facilities, is suggested to decrease the number of collision injuries. Coaches should be cognisant of overtraining, vary day-to-day training routines to decrease repetitive musculoskeletal stress, focus on motor skills with equal emphasis on speed and efficiency of movement, and use drills that reinforce sport-specific, decision making processes to minimise mental mistakes. Conditioning programs that emphasise a combination of power, acceleration, flexibility, technical skill, functional capacity and injury prevention are recommended. Due to the limited body of knowledge presently available on this sport, a greater focus on injury surveillance would provide a clearer picture of injury causation and effective management procedures, leading toward safer participation and successful player development.


Assuntos
Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/prevenção & controle , Beisebol/lesões , Prevenção Primária/métodos , Adolescente , Adulto , Distribuição por Idade , Feminino , Humanos , Incidência , Masculino , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
2.
IEEE Trans Image Process ; 10(5): 767-82, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249666

RESUMO

Many electronic watermarks for still images and video content are sensitive to geometric distortions. For example, simple rotation, scaling, and/or translation (RST) of an image can prevent blind detection of a public watermark. In this paper, we propose a watermarking algorithm that is robust to RST distortions. The watermark is embedded into a one-dimensional (1-D) signal obtained by taking the Fourier transform of the image, resampling the Fourier magnitudes into log-polar coordinates, and then summing a function of those magnitudes along the log-radius axis. Rotation of the image results in a cyclical shift of the extracted signal. Scaling of the image results in amplification of the extracted signal, and translation of the image has no effect on the extracted signal. We can therefore compensate for rotation with a simple search, and compensate for scaling by using the correlation coefficient as the detection measure. False positive results on a database of 10,000 images are reported. Robustness results on a database of 2000 images are described. It is shown that the watermark is robust to rotation, scale, and translation. In addition, we describe tests examining the watermarks resistance to cropping and JPEG compression.

3.
IEEE Trans Image Process ; 5(3): 551-3, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18285143

RESUMO

The article describes a new image transform that decomposes an image using a set of Gaussian derivatives. The basis functions themselves have been shown to effectively model the measured receptive fields of simple cells in the mammalian visual cortex. Based on these functions, it can be expected that this transform can provide a mechanism for exploiting the properties of the human visual system in image processing algorithms.

4.
Can Fam Physician ; 39: 2337-45, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8268741

RESUMO

Forty-seven patients older than 65 years were randomly selected for structured chart review of all long-term medications documented during the prior year and the number of instances of potentially undesirable prescribing for each patient. A trained nurse subsequently made home visits to assess all long-term medications used regularly during the same period. Forty-five percent of elderly patients had one or more instances of potentially undesirable drug use, all of which appeared to be readily remediable. Commercial drug interaction software identified less than half of the potentially undesirable instances.


Assuntos
Prescrições de Medicamentos/estatística & dados numéricos , Tratamento Farmacológico/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Medicina de Família e Comunidade/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Idoso , Interações Medicamentosas , Tratamento Farmacológico/classificação , Uso de Medicamentos , Feminino , Humanos , Masculino , Auditoria Médica , Projetos Piloto , Estudos de Amostragem
5.
J Histochem Cytochem ; 32(6): 608-16, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6725935

RESUMO

A simple hemolytic assay of the photodamage suffered by individual intact erythrocytes upon localized exposure to high laser intensities such as those encountered in fluorescence photobleaching recovery (FPR) experiments has been characterized. At incident beam powers over 100,000 W/cm2 at 514 or 568 nm, hemoglobin absorption induces thermal-shock lysis. Below the thermal-shock threshold, other intracellular chromophores appear to catalyze membrane contraction and lysis with linear dose kinetics in anaerobic preparations. A variety of chemical agents that inhibit photodamage to red cell ghost membranes at low intensities (less than 450 W/cm2) do not benefit intact cells at realistic FPR bleaching doses of 10,000 to 1,000,000 W/cm2. However, we find that sample deoxygenation dramatically photostabilizes erythrocytes, thus we have developed a physiologically compatible in situ deoxygenation method utilizing submitochondrial particles. The extent to which this and other deoxygenation procedures modify fluorophore photolability has been determined. FPR measurements become practical on intact erythrocytes when a combination of low bleach power, thorough deoxygenation, and long wavelength excitable (approximately 650 nm) fluorescence probes is employed; the equivalent of 60,000 photobleaches per cell can then be tolerated without detectable damage.


Assuntos
Membrana Eritrocítica/efeitos da radiação , Lasers , Fotólise , Animais , Estabilidade de Medicamentos , Membrana Eritrocítica/ultraestrutura , Fluoresceína , Fluoresceínas/efeitos da radiação , Corantes Fluorescentes , Hemólise , Camundongos , Oxigênio/sangue , Fotoquímica , Partículas Submitocôndricas/fisiologia , Succinatos/farmacologia , Ácido Succínico
6.
Biophys J ; 42(3): 295-305, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6603237

RESUMO

The lateral diffusion of fluorescent lipid analogues in the plasma membrane of intact erythrocytes from man, mouse, rabbit, and frog has been measured by fluorescence photobleaching recovery (FPR). Intact cells from dystrophic, normoblastic, hemolytic, and spherocytotic mouse mutants; from hypercholesterolemic rabbits and humans; and from prenatal, neonatal, and juvenile mice have been compared with corresponding normals. The lateral diffusion coefficient (D) for 3,3'-dioctadecylindodicarbocyanine iodide (DiI[5]) in intact normal human erythrocytes is D = 8.2 +/- 1.2 X 10(-9) cm2/s at 25 degrees C and D = 2.1 +/- 0.4 X 10(-8) cm2/s at 37 degrees C, and varies approximately 50-fold between 1 degree and 42 degrees C. The diffusion constants of lipid analogue rhodamine-B phosphatidylethanolamine (RBPE) are about twice those of DiI[5]. The temperature dependence and magnitude of D vary by up to a factor of 3 between species and are only influenced by donor age in prenatals. DiI[5] diffusibility is not perturbed by the presence of calcium or local anesthetics or by spectrin depletion (via mutation). However, lipid-analogue diffusibility in erythrocyte ghosts may differ from intact cells. Dietary hypercholesterolemia in rabbits reduces the diffusion coefficient and eliminates the characteristic break in Arrhenius plots of D found in all other cells studied except frog.


Assuntos
Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Lipídeos de Membrana/sangue , Animais , Difusão , Feminino , Feto , Humanos , Hipercolesterolemia/sangue , Camundongos , Distrofia Muscular Animal/sangue , Fotólise , Gravidez , Coelhos , Rana pipiens , Especificidade da Espécie , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos
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