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The conversion coefficients (CCs) relate protection quantities, mean absorbed dose (DT) and effective dose (E), with physical radiation field quantities, such as fluence (Φ). The calculation of CCs through Monte Carlo simulations is useful for estimating the dose in individuals exposed to radiation. The aim of this work was the calculation of conversion coefficients for absorbed and effective doses per fluence (DT/ Φ and E/Φ) using a sitting and standing female hybrid phantom (UFH/NCI) exposure to monoenergetic protons with energy ranging from 2 MeV to 10 GeV. The radiation transport code MCNPX was used to develop exposure scenarios implementing the female UFH/NCI phantom in sitting and standing postures. Whole-body irradiations were performed using the recommended irradiation geometries by ICRP publication 116 (AP, PA, RLAT, LLAT, ROT and ISO). In most organs, the conversion coefficients DT/Φ were similar for both postures. However, relative differences were significant for organs located in the abdominal region, such as ovaries, uterus and urinary bladder, especially in the AP, RLAT and LLAT geometries. Anatomical differences caused by changing the posture of the female UFH/NCI phantom led an attenuation of incident protons with energies below 150 MeV by the thigh of the phantom in the sitting posture, for the front-to-back irradiation, and by the arms and hands of the phantom in the standing posture, for the lateral irradiation.

The accidental introduction of the Brown Tree Snake Boiga irregularis to Guam has resulted in the extirpation of most of the island's native terrestrial vertebrates, has created a health hazard to infants and children, and has resulted in economic losses. Cargo inspections using teams of handlers and their detector dogs form a last line of defense for preventing Brown Tree Snake dispersal from Guam. To assess the efficacy of the teams of handlers and their dogs for locating stowed Brown Tree Snakes, we planted Brown Tree Snakes (in escape-proof containers) in cargo without the knowledge of the handlers inspecting the cargo. We found that when an observer attended the inspection to monitor procedures, 80% of the planted snakes were located. Without an attending observer present, 70% of the planted snakes were discovered, but only after such plantings had become a routine procedure. Prior to the routine planting of snakes, efficacy was nearly 50% less (38%). The reasons some planted snakes were missed by the dog teams were split between: an insufficient search pattern by the handler, or the dog giving no discernable indication that a snake was present.

Objetivou-se caracterizar a composição florística e fitossociológica do componente florestal lenhoso em um fragmento de Caatinga localizada no município de Upanema-RN. Realizou-se o levantamento por meio da Amostragem Aleatória Simples, instalando-se 11 unidades amostrais de 20 x 20 m (400 m²). Em cada unidade amostral foram inventariados todos os indivíduos florestais arbustivos arbóreos vivos que apresentaram circunferência a altura do peito maior que seis centímetros (CAP ≥ 6 cm). Avaliou-se os parâmetros fitossociológicos da estrutura horizontal e vertical, a diversidade florística das espécies através do Índice de Shannon-Weaver (H'), dominância de Simpson (C) e equabilidade de Pielou (J'). A família com maior número de espécies e de indivíduos foi a Fabaceae. As espécies com maior importância na área de estudo sob os aspectos fitossociológicos foram Combretum leprosum, Aspidosperma pyrifolium, Bauhinia cheilantha, Mimosa ophthalmocentra e Poincianella pyramidalis. A diversidade de espécie encontrada na área foi considerada média se comparada com outros fragmentos florestais de caatinga já estudados. Palavras-chave: diversidade florística, estrutura horizontal, vegetação de caatinga. Floristic-phytosociological characterization of the woody component in a caatinga fragment in the municipality of Upanema-RN, Brazil

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