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1.
Health Phys ; 119(2): 206-215, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-33290003

RESUMEN

A previous study reported thermal effects resulting from millimeter wave exposures at 35 and 94 GHz on non-human primates, specifically rhesus monkeys' (Macaca mulatta) corneas, but the data exhibited large variations in the observed temperatures and uncertainties in the millimeter wave dosimetry. By incorporating improvements in models and dosimetry, a non-human primate experiment was conducted involving corneal exposures that agreed well with a three-layer, one-dimensional, thermodynamic model to predict the expected surface temperature rise. The new data indicated that the originally reported safety margins for eye exposures were underestimated by 41 ± 20% over the power densities explored. As a result, the expected minimal visible lesion thresholds should be raised to 10.6 ± 1.5 and 7.1 ± 1.0 J cm at 35 and 94 GHz, respectively, provided that the power density is less than 6 W cm for subjects that are unable to blink. If the blink reflex was active, a power density threshold of 20 W cm could be used to protect the eye, although the eyelid could be burned if the exposure was long enough.


Asunto(s)
Córnea/efectos de la radiación , Fenómenos Fisiológicos Oculares/efectos de los fármacos , Algoritmos , Animales , Temperatura Corporal , Simulación por Computador , Relación Dosis-Respuesta en la Radiación , Células Epiteliales/efectos de la radiación , Macaca mulatta , Microondas , Modelos Teóricos , Dosis de Radiación , Exposición a la Radiación , Ondas de Radio , Radiometría , Piel/citología , Factores de Tiempo
2.
J Forensic Sci ; 54(5): 1113-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19737245

RESUMEN

Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a "Modifiable Electronic Stimulator" was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26-like pulses did not have a significant effect on the normalized force measured. Muscle-contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26-like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26-type device that operates efficiently at levels higher than the X26.


Asunto(s)
Electrochoque/instrumentación , Contracción Muscular , Fibrilación Ventricular , Animales , Electrocardiografía , Diseño de Equipo , Medicina Legal , Miembro Posterior , Modelos Animales , Sus scrofa
3.
Forensic Sci Med Pathol ; 5(1): 2-10, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19330471

RESUMEN

In previous studies, repeated 5-s exposures of anesthetized pigs to an electronic control device (TASER International's Advanced TASER X26 device) resulted in acidosis and increases in blood electrolytes. In the current study, experiments were performed to investigate the effects of longer continuous exposures to a different electronic-control-device waveform. After intramuscular injection of tiletamine HCl and zolazepam HCl, anesthesia was maintained with propofol infusion. Ten pigs were exposed to either 30- or 60-s applications of an electronic waveform similar to the TASER-X26 device. Transient increases in potassium, and sodium were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. Blood pH was significantly decreased after exposure, but subsequently returned to baseline levels. Lactate was highly elevated and remained somewhat increased even after three hrs. Serum myoglobin was increased after exposure and remained elevated for the 3-h follow-up period. Acidosis would appear to be one of the major concerns with long-duration (e.g., several min) exposures over a short period of time. Even with the extremely low pH immediately after exposure, all animals survived. On the basis of these results, further development of useful continuous-exposure electronic control devices is at least feasible, with the caveat that some medical monitoring of subjects may be required.


Asunto(s)
Electrochoque/instrumentación , Animales , Análisis Químico de la Sangre , Glucemia/análisis , Dióxido de Carbono/sangre , Creatina Quinasa/sangre , Medicina Legal , Frecuencia Cardíaca , Hematócrito , Concentración de Iones de Hidrógeno , Ácido Láctico/sangre , Masculino , Contracción Muscular , Mioglobina/sangre , Oxígeno/sangre , Potasio/sangre , Respiración , Sodio/sangre , Sus scrofa , Factores de Tiempo
4.
Forensic Sci Int ; 175(2-3): 166-70, 2008 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-17630236

RESUMEN

In a previous study, 18 repeated exposures of anaesthetized swine to an electro-muscular incapacitating device (TASER International's ADVANCED TASER X26 electronic control device) resulted in acidosis and increases in blood electrolytes. In the current study, experiments were performed to investigate effects of a more typical scenario of repeated exposures of the device on muscle contraction and changes in blood factors. Ten swine were exposed for 5s, followed by a 5-s period of no exposure, three times. Selected blood factors were monitored for 3h following exposure. Transient increases in blood glucose, lactate, sodium, potassium, calcium, and pCO(2) were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. Blood pH was decreased immediately following exposure, but subsequently returned toward a normal level. Oxygen saturation (measured by pulse oximetry) was not changed significantly. In conclusion, three repeated TASER device exposures had only transient effects on blood factors, which all returned to pre-exposure levels, with the exception of hematocrit (which remained elevated after 3h). Since the increase in this factor was less than that which may occur after short periods of exercise, it is unlikely that this would be an indicator of any serious harm.


Asunto(s)
Electrochoque/instrumentación , Animales , Glucemia/análisis , Calcio/sangre , Dióxido de Carbono/sangre , Creatina Quinasa/sangre , Medicina Legal , Frecuencia Cardíaca/fisiología , Hematócrito , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/sangre , Masculino , Contracción Muscular/fisiología , Mioglobina/sangre , Oxígeno/sangre , Potasio/sangre , Respiración , Sodio/sangre , Sus scrofa , Troponina I/sangre , Troponina T/sangre
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