RESUMEN
Wild bearded capuchins (Cebus libidinosus, quadrupedal, medium-sized monkeys) crack nuts using large stones. We examined the kinematics and energetics of the nut-cracking action of two adult males and two adult females. From a bipedal stance, the monkeys raised a heavy hammer stone (1.46 and 1.32 kg, from 33 to 77% of their body weight) to an average height of 0.33 m, 60% of body length. Then, they rapidly lowered the stone by flexing the lower extremities and the trunk until the stone contacted the nut. A hit consisting of an upward phase and a downward phase averaged 0.74 s in duration. The upward phase lasted 69% of hit duration. All subjects added discernable energy to the stone in the downward phase. The monkeys exhibited individualized kinematic strategies, similar to those of human weight lifters. Capuchins illustrate that human-like bipedal stance and large body size are unnecessary to break tough objects from a bipedal position. The phenomenon of bipedal nut-cracking by capuchins provides a new comparative reference point for discussions of percussive tool use and bipedality in primates.
Asunto(s)
Cebus/fisiología , Conducta Alimentaria/fisiología , Nueces , Comportamiento del Uso de la Herramienta/fisiología , Animales , Fenómenos Biomecánicos , Brasil , Femenino , Masculino , Grabación en VideoRESUMEN
OBJECTIVE: Scientifically based injury prevention efforts have not been widely implemented in Latin America. This study was undertaken to evaluate the baseline knowledge and practices of childhood safety on the part of parents in Monterrey, Mexico and in so doing provide information on which to base subsequent injury prevention efforts. METHODS: Interviews were carried out with parents from three socioeconomic strata (upper, middle, lower). Questionnaires were based on Spanish language materials developed by The Injury Prevention Program (TIPP) of the American Academy of Pediatrics. RESULTS: Data were obtained from parents of 1123 children. Overall safety scores (percent safe responses) increased with increasing socioeconomic status. The differences among the socioeconomic groups were most pronounced for transportation and less pronounced for household and recreational safety. The differences were most notable for activities that required a safety related device such as a car seat, seat belt, helmet, or smoke detector. Appropriate use of such devices declined from 47% (upper socioeconomic group) to 25% (middle) to 15% (lower). CONCLUSIONS: Considerable differences in the knowledge and especially the practice of childhood safety exist among parents in different socioeconomic levels in Mexico. Future injury prevention efforts need to address these and especially the availability, cost, and utilization of specific highly effective safety devices.
Asunto(s)
Equipos de Seguridad/estadística & datos numéricos , Heridas y Lesiones/prevención & control , Niño , Protección a la Infancia , Preescolar , Femenino , Humanos , Lactante , Masculino , México/epidemiología , Padres , Seguridad , Factores Socioeconómicos , Encuestas y Cuestionarios , Salud Urbana , Heridas y Lesiones/epidemiologíaRESUMEN
This paper is aimed at providing a comprehensive review of markers, cofactors and staging systems used for HIV disease, focusing on some aspects that nowadays could even be considered historical, and advancing in current issues such as the prognostic value of viral load measurements, viral genotypic and phenotypic characterization, and new HIV disease treatment protocols. CD4 cell values, combined with the new viral markers mentioned are promising as a parsimonious predictor set for defining both severity and progression. An adequate predictor of patient resource use for planning purposes still needs to be defined.
Asunto(s)
Humanos , VIH/crecimiento & desarrollo , Síndrome de Inmunodeficiencia Adquirida/clasificación , Progresión de la Enfermedad , Biomarcadores/análisisRESUMEN
This paper is aimed at providing a comprehensive review of markers, cofactors and staging systems used for HIV disease, focusing on some aspects that nowadays could even be considered historical, and advancing in current issues such as the prognostic value of viral load measurements, viral genotypic and phenotypic characterization, and new HIV disease treatment protocols. CD4+ cell values, combined with the new viral markers mentioned are promising as a parsimonious predictor set for defining both severity and progression. An adequate predictor of patient resource use for planning purposes still needs to be defined.
Asunto(s)
Infecciones por VIH/clasificación , Biomarcadores , Progresión de la Enfermedad , Infecciones por VIH/diagnóstico , HumanosRESUMEN
STUDY OBJECTIVE: To determine the potentiation of the neuromuscular blockade induced by a titrated infusion of mivacurium in the presence of isoflurane versus a nitrous oxide (N2O)-opioid anesthesia. DESIGN: An open-label, controlled study. SETTING: The inpatient anesthesia service of two university medical centers. PATIENTS: Thirty adults divided into two groups. INTERVENTION: An intravenous infusion of mivacurium during anesthesia with N2O-opioid or N2O-isoflurane. MEASUREMENTS AND MAIN RESULTS: A neuromuscular blockade was monitored by recording the electromyographic activity of the adductor pollicis muscle resulting from supramaximal stimulation at the ulnar nerve at 2 Hz for 2 seconds at 10-second intervals. The mivacurium infusion rate was significantly less in the presence of isoflurane [4.0 +/- 0.8 micrograms/kg/min (mean +/- SEM)] than during N2O-opioid anesthesia (6.4 +/- 0.6 micrograms/kg/min). The recovery rates did not differ between anesthetic groups. After the termination of the infusion, spontaneous recovery to T4/T1 of at least 0.75 occurred in an average of 17.9 +/- 1.5 minutes, with a mean recovery index (T25-75) of 6.0 +/- 0.7 minutes. CONCLUSION: Isoflurane anesthesia reduces the infusion rate of mivacurium required to produce about 95% depression of neuromuscular function.