Effect of windows and doors on the gamma shielding factor for typical houses in Brazil.

This study aims to determine the effect of windows and doors on shielding factors, defined as the ratios of the air kerma indoor to the air kerma in an open field, for typical building materials used in the southeast of Brazil due to radioactive material deposited on the surrounding field, walls, and ceiling external surfaces. The MCNP5 Monte Carlo radiation transport code was used in the simulation of photon shielding. The air kerma indoors for monoenergetic photons of 300 keV, 662 keV, and 3,000 keV has been determined for three different housing patterns, ranging from a poorly constructed house, at a density thickness of 5.5 g cm(-2) for the walls, to a well-constructed house, at a density thickness of 13.1 g cm(-2) for the walls, both with and without the presence of windows and doors. The shielding factor for the poorly constructed house type at an incident photon energy of 300 keV was found to be twice that of the well-constructed house type for the same energy. The presence of windows and doors showed very little or no significant increase on the shielding factors for the building materials studied. The maximum increase was found to be 9% for the well-constructed house type at a incident photon energy of 300 keV.

Antinocicepción opioide del extracto metanólico del Chuchuhuasi (Maytenus krukovii) en un modelo de dolor visceral en rat¢n / Antinociceptive opioid of chuchuhuasi Maytenus krukoviimethanolic extract in a model of visceral pain in mice

Evaluamos la acción antinociceptiva del extracto metanólico del Chuchuhuasi (Maytenus krukovii), al 20%, administrado por vía oral, en ratones albinos, machos, raza Webster Suizo obtenidos del Centro Nacional de Produccón de Biológicos del Ministerio de Salud del Peru, utilizando un modelo de dolor visceral, mediante la administración de  ácido acático al 2%, vía intraperitoneal, a la dosis de 0,05 ml/10g de peso. Observamos una disminución del 50% del número de contorsiones abdominales, en relación al grupo control, sin prolongación del período de latencia de las mismas. El efecto analgésico observado, fue bloqueado por la naloxona, lo que sugeriría la participación de receptores opioides, o de opioides endógenos en el mecanismo de la acción analgésica. Los resultados fueron analizados estadísticamente mediante el programa estadístico SPSS versión 11.5.

We evaluated the antinociceptive action of a 20% Chuchuhuasi (Maytenus krukovii) methanolic extract administered by oral route, on male albino Swiss Webster mice, from the Peruvian Health Institute, using a model of visceral pain. Intraperitoneal injections of 2% acetic acid at a concentration of 0,05 ml/10g were administered. We found a decrease of 50% in the average number of abdominal cramps, related to the control group, without increase of the latency period of abdominal contortions. The analgesic action was blocked by naloxone and could imply the participation of opioid receptors or endogenous opioids as the mechanism of action. Data were analyzed statistically with the SPSS program version 11.5.

Gamma shielding factor for typical houses in Brazil.

The housing features in a country depend much on its climate. Dwellings in warm countries are much lighter constructions than in cold ones, which will reflect on the amount of shielding against radiation they provide. In addition to that, wealth is another factor that influences the building's finishing. Great effort has been taken to determine parameters to more accurately estimate dose to a population in case of a radioactive or nuclear accident. Nevertheless, most available data are concerned with typical housing in cold climate countries. This study aims to determine shielding factors for typical building materials used in the southeast of Brazil, a warm area, due to radioactive material deposited on the surrounding field, walls and ceiling of the external surfaces. The shielding factors determination was performed by simulation with the MCNP5 Monte Carlo computer code. The air kerma indoors for the 300, 662 and 3000 keV photon energies have been determined for three different housing patterns, ranging from the very simple to a very complex structure. The shielding factor, defined as the ratio of the air kerma indoor to the air kerma in open field, for the most simple house type and 300 keV photon energy was found to be twice of the best finished one for the same energy.

Effective density and mass attenuation coefficient for building material in Brazil.

This paper presents values for density and mass attenuation coefficient of building materials commonly used in Brazil. Transmission measurements were performed to provide input information for simulations with MCNP4B code. The structure for the clay bricks was simulated as a mix of all material layers and an effective density determined. The mass attenuation coefficients were determined for the 50-3,000 keV gamma-ray energy range. A comparison with results for similar materials found in the literature showed good agreement.

[Cardiovascular risk factors in children and teenagers aged 6-18 years old from Medellin (Colombia)]. / Factores de riesgo cardiovascular en niños de 6 a 18 años de Medellín (Colombia).

OBJECTIVE: To evaluate exposure to the major risk factors for cardiovascular disease in children from Medellín according to age, sex, type of school, and socioeconomic status. METHOD: We performed a descriptive study in 2611 children aged 6-18 years old from the city of Medellín in Colombia. Lipid profile, blood pressure, body mass index, diet, exercise, alcohol intake, and smoking were evaluated. RESULTS: Forty-six percent of the children drank alcohol, 8.7 % smoked and 50 % were physically inactive. Fat and carbohydrate intake was high in 48 % and 47 %, respectively. A total of 9.3 % of the children were overweight and 4.6 % were obese. Systolic and diastolic blood pressure were high in 1.3 % and 3.9 %, respectively. Mean high-density lipoprotein cholesterol (HDL-C) values were lower than in other populations, while triglyceride values were higher. Differences in serum lipid concentrations were found according to age and sex. The prevalence of risk factors according to the National Cholesterol Education Program criteria were: 19.1 % for HDL-C, 17.1 % for triglycerides, 17.0 % for low-density lipoprotein cholesterol (LDL-C), 13.5 % for total cholesterol (TC) and 22.9 % for TC/HDL-C. CONCLUSIONS: In children from the city of Medellín, the most prevalent cardiovascular risk factors were related to lifestyle. Mean plasma lipid concentrations varied according to age and sex. The prevalence of overweight was higher than in other populations in Colombia but was lower than that reported for other countries.