[en] Published in summary form only

[en] We calculate the one-loop electroweak corrections to the decay t->bW⁺, including the counterterm for the CKM matrix elements V_tb. Previous calculations used an incorrect δV_tb that led to a gauge dependent amplitude. However, since the contribution stemming from δV_tb is small, those calculations only underestimate the width by roughly 1 part in 10⁵

No abstract available

[en] With the aim of analysing protection of patient in diagnostic nuclear medicine, this study present data collected from sixteen nuclear medicine public and private institutions in three regions of the country, namely Northeast, Southeast and South regions 26,782 patients protocols were analysed, 24,371 adults and 2,411 children and teen-ages. Myocardial perfusion and bone imaging were responsible, respectively, for 53% and 23% of all diagnostic procedures. For 3.010 adults with age and weight registered, 96% had more than 40 years and mean weight was (69.9±14.1) kg for both genders. Due to similarities in physical characteristics between Brazilian adults patients and ICRP Reference Man, effective doses were estimated using ICRP conversion factors. For adults, the ratio mean activities per mean weigh was higher for female than male for the majority of procedures. For children and teen-ages, this ratio was higher for younger ages. Protocols should consider mean corporal weight for female and activities may be reduced accordingly. For children and teen-ages, effective doses may be reduced for younger ages. High absolved doses in bone surfaces of children due to 67Ga citrate imaging and bone scintigraphies should be investigated. (Author)

[en] The heating of H II regions by electrons ejected from grains after absorption of stellar and diffuse photons is considered. This mechanism is compared with photoionization heating, taking into account central stars in different positions on the HR diagram. The grain contribution to electron temperature is also examined, and the results indicate the position on the HR diagram where grain contribution is likely to be important. (author)

No abstract available

[en] Krylov subspace methods are used for solving the transport equations in a slab geometry. The spatial discretization scheme used is a finite element method called Modified Linear Discontinuous scheme. It is s investigated the convergence rates for a number of Krylov subspace methods for this problem and compared with the results of a spatial multigrid scheme. (author). 10 refs, 3 figs, 3 tabs

[en] The method used for to measure the Spectrum indice and all the technical apparatus used for the utilization of fission chambers are showed. The computer codes used for interpretation the measuring, are described. (E.G.)

[en] Results of data treatment related to Regional Geochemical Surveys developed by DINAMIGE in cooperation with BRGM (France) during the last decade were discussed. Methodological and analytical problems were indicated. The resulting geochemical maps reflected quite well the lithological varieties and the ore occurrences. However, new geochemical data are needed, taking into account new methodological approaches. (author)

[en] Full text: Objective: To evaluate the utility of 99mTc-HMPAO labeled leucocyte, 99mTc-labeled anti-granulocyte antibody and 67Ga scintigraphy in patients suspected to have infected hip and knee replacements, from March/1998 to March/ 2002. Methods: Retrospective study of 33 patients (12 male, 21 female) with an average age of 61,1 ± 7,3 years. Nineteen had hip replacements and 14 were submitted to knee replacements. 99mTc-HMPAO labeled leucocyte scintigraphy was performed in 17 patients, 99mTc-labeled anti-granulocyte antibody scintigraphy in 13 patients and 67Ga scintigraphy in 3 patients. Twenty-six patients were also submitted to 3-phase 99mTc-MDP bone scintigraphy. Results were compared to those from studies with infection/inflammation agents. Concordant positive studies were considered to be a positive result for infection. A second study using 67Ga was also performed in 3 patients. Results: Diagnosis was based on surgical findings in 14 patients, pathologic study of biopsy specimen in 1 case and clinical/ imaging follow-up in 18 patients. Infection was detected in 22 cases and absent in 11. The conjoined evaluation of scintigraphic studies considered infection to be present in 20 cases and absent in 13. With infection/inflammation agents, 20 cases were positive (+) and 13 cases were negative (-). Using 99mTc-HMPAO labeled leucocytes, 12 cases were (+) and 5 cases were (-). With 99mTc-labeled anti-granulocyte antibodies, 8 cases were (+) and 5 were (-). With 67Ga, all 3 cases were (-). In patients with (+) studies using infection/ inflammation agents, a false positive case with 99mTc-HMPAO labeled leucocytes was reported. Two false negative cases were detected, both with 99mTc-labeled antigranulocyte antibodies, in patients with (-) studies. Regarding the studies with 99mTc-MDP, 24 were (+) and 2 were (-). Eighteen of these (+) cases were also (+) in studies with infection/inflammation agents, but 6 were (-) with these agents. Negative cases were also (-) in studies with infection/inflammation agents. Conclusions: Scintigraphy with infection/ inflammation agents yielded a sensitivity of 91%, a specificity of 92%, a PPV of 95%, a NPV of 85% and a diagnostic accuracy of 85%. Bone scintigraphy yielded sensitivity, specificity, PPV and NPV values of 100%, 56%, 50% and 100%, respectively. (author)