Search

Curative treatment of thyroid cancer is a major issue for patients with end stage renal disease (ESRD) undergoing dialysis because they might not be included in a renal transplant protocol once they have overcome this disease. Since 131I is mostly eliminated by the kidneys, there is concern regarding the toxicity, efficacy and feasibility of 131I-therapy of anuric dialyzed patients.This paper reports on 131I uptake and elimination from remnant thyroid tissue (T), salivary glands (SG), stomach (S) and blood, after administration of 3.7 GBq of 131I for 2 patients on twice weekly dialysis for ESRD.Compared to normal renal function patients, radio-iodine recirculation is observed, and SG and blood irradiation is about 6 times higher, but the dose delivered to the thyroid is not significantly enhanced. Dialysis removes more 131I from SG, S and blood than from T. Anticipated dialysis will reduce irradiation by 38% for the blood, 45% for SG and 34% for T.Therefore, a higher 131I amount could then be used, providing that accurate personalized dosimetry is previously performed using 131I pharmacokinetic models. Concerning radiation protection issues, no significant dialysis equipment contamination is noted, and nurses and medical staff exposure remains below 0.2 mSv.

Ground penetrating radar is usually employed for non-destructive evaluations and maintenance of roads and bridges. This report describe the study of an emlbankmet where a bridge will be built due to the construction of a new road. The geology In this place, where the foundations of the bridge will be emplaced, are formed by hint sands layers between conglomerates ones. Flowing water eroses the sand causing holes and possible landslides, which could be damaging for the bridge. The study of the embakment with aground penetrating radar allows to know the thickness o f the sand layers and the posible holes placed into them. An antenna with center frecuency 100 MHz was used attending the characteristics o f the emplacement. The radar data shows among some other things, the different reflectors due to the conglomerate, the sand layers and their thicknesses. The presence and the emplacement of several holes in the layers are also observed. These results show where the foundations must be properly placed. A comparison with a geological profile was perfomed to assure the results

The opening of abandoned salt mines whit the idea of prepare cultural routes requires the use of hard machinery in abandoned places. The erosion caused by salt disolutions damage the mine structure, being dangerous for restoration and visiting purposes. Planed jobs were the opening of a new gallery to prepare a round route and restoring the part of the salt mine that will be open to the public. Ground penetrating measurements have been used, first to locate the position and depth of underground scour holes and subsurface voids in the ground and in the solid salt mountain, and second, to study the vault and gables end in the salt mine galleries. Three antennas were used in his job, with WO MHz, 300 MHz and 500 MHz center frecuencies.. Radar data has locate holes in the first meters under the floor of the mine galleries and into the contact between the salt mountain and the cover materials. The analisys of the anomalies also shows scour holes in to the slag heap caused by the flowing water which eroses the soft materials. These areas are not safety places for mining jobs. This work try to provide safety measurements to the salt mine workers and try to assists to the tourist mine maintenance planning

The vault damage in a railway tunnel, caused by damps in a granite massif, produced the granite slabs roof detachment. Sustitution of these granite slabs by concrete, including damping voids between the roof and the granite massif, was the most optimal solution concerning the preservation of the railway interior tunnel size (gallbo). The volume of concrete necessary to cover the vault and the gables of the tunnel was determined using a ground penetrating radar SIR 70 from GSSI, with a 500 MHz center frecuency antenna. Twelve radar profiles along the tunnel, covering the vault and the tunnel walls, were made to determine the total volume of concrete necessary to replace the old granite slabs, the void location and the identification of the tunnel region to be repaired. Ground penetrating radar measurements allowed to know the thicknesses of the granite slabs and the distance between these slabs and the massif rock of the irregular void

Ground penetrating radar is usually employed for non-destructive evaluations and maintenance of roads and bridges. This report describe the study of an emlbankmet where a bridge will be built due to the construction of a new road. The geology In this place, where the foundations of the bridge will be emplaced, are formed by hint sands layers between conglomerates ones. Flowing water eroses the sand causing holes and possible landslides, which could be damaging for the bridge. The study of the embakment with aground penetrating radar allows to know the thickness o f the sand layers and the posible holes placed into them. An antenna with center frecuency 100 MHz was used attending the characteristics o f the emplacement. The radar data shows among some other things, the different reflectors due to the conglomerate, the sand layers and their thicknesses. The presence and the emplacement of several holes in the layers are also observed. These results show where the foundations must be properly placed. A comparison with a geological profile was perfomed to assure the results

The opening of abandoned salt mines whit the idea of prepare cultural routes requires the use of hard machinery in abandoned places. The erosion caused by salt disolutions damage the mine structure, being dangerous for restoration and visiting purposes. Planed jobs were the opening of a new gallery to prepare a round route and restoring the part of the salt mine that will be open to the public. Ground penetrating measurements have been used, first to locate the position and depth of underground scour holes and subsurface voids in the ground and in the solid salt mountain, and second, to study the vault and gables end in the salt mine galleries. Three antennas were used in his job, with WO MHz, 300 MHz and 500 MHz center frecuencies.. Radar data has locate holes in the first meters under the floor of the mine galleries and into the contact between the salt mountain and the cover materials. The analisys of the anomalies also shows scour holes in to the slag heap caused by the flowing water which eroses the soft materials. These areas are not safety places for mining jobs. This work try to provide safety measurements to the salt mine workers and try to assists to the tourist mine maintenance planning

Several kilometers o f tunnel have been excavated to extend a metropolitan underground system. In some places, where the subsurface is mainly composed by gravel and sands, water can easly penetrate causing problems to the tunnel and the stations. In order to avoid such problems, a jet-grouting injection was carried out. To check the continuity of the jet-grouting a Ground Penetrating Radar analysis was applied. The radar used is a SIR 10 of Geophysical Survey Systems Inc., with a center frecuency antenna of 100 Mz, prepared for urban jobs. A good determination of the variantion of the thickness of the jet-grouting layer was obtained, although several difficulties, specially the irregular topography, were to be solved. Three boreholes to determine the quality and thickness of the jet-grouting in three different places provided the right calibration of the involved radargrams. During the processing of the data, several filters had to be applied to discriminate the radar signals from noise, coming mainly from the electrical system of the tunnel

Accurate identification of frames into concrete reinforced walls in a nuclear power plant was required because of maintenance labours. Several cuts in the concrete, including the frame, were planned. The cutting lines were designed to avoid as much as possible the frame bars. To perfom this work the ground penetrating radar has been used. The use of ground prenetrating radar techniques allow to determine the vertical and horizontal position of the frame bars. GPR detects also other reflectors in to the walls. The ele ctric propertie s contrast betw een the concrete and th e steel o f the frame gives reflections clearly detected in the records. This near surface study requires to use high resolution antennas with a very high center frecuency. The measurement precision required In the work was obtained using a special marker to carry the antenna, specially design for this job. The marker allows to know the position of the antenna on the wall with a precission of centimeters. The measurements were acquired from one antenna with a center frecuency of 1000 MHz, with a SIR 10 system of Geophysical Survey Sistems Inc.. An experimental test made in a scale model help to the interpretation of the records.. A later and careful treatment in laboratory, using all the records obtained in the nuclear power plant, applying vertical lowpass and highpass filters and horizontal lowpass filter was perfomed, to place correctly the bars into the concrete

The vault damage in a railway tunnel, caused by damps in a granite massif, produced the granite slabs roof detachment. Sustitution of these granite slabs by concrete, including damping voids between the roof and the granite massif, was the most optimal solution concerning the preservation of the railway interior tunnel size (gallbo). The volume of concrete necessary to cover the vault and the gables of the tunnel was determined using a ground penetrating radar SIR 70 from GSSI, with a 500 MHz center frecuency antenna. Twelve radar profiles along the tunnel, covering the vault and the tunnel walls, were made to determine the total volume of concrete necessary to replace the old granite slabs, the void location and the identification of the tunnel region to be repaired. Ground penetrating radar measurements allowed to know the thicknesses of the granite slabs and the distance between these slabs and the massif rock of the irregular void

Accurate identification of frames into concrete reinforced walls in a nuclear power plant was required because of maintenance labours. Several cuts in the concrete, including the frame, were planned. The cutting lines were designed to avoid as much as possible the frame bars. To perfom this work the ground penetrating radar has been used. The use of ground prenetrating radar techniques allow to determine the vertical and horizontal position of the frame bars. GPR detects also other reflectors in to the walls. The ele ctric propertie s contrast betw een the concrete and th e steel o f the frame gives reflections clearly detected in the records. This near surface study requires to use high resolution antennas with a very high center frecuency. The measurement precision required In the work was obtained using a special marker to carry the antenna, specially design for this job. The marker allows to know the position of the antenna on the wall with a precission of centimeters. The measurements were acquired from one antenna with a center frecuency of 1000 MHz, with a SIR 10 system of Geophysical Survey Sistems Inc.. An experimental test made in a scale model help to the interpretation of the records.. A later and careful treatment in laboratory, using all the records obtained in the nuclear power plant, applying vertical lowpass and highpass filters and horizontal lowpass filter was perfomed, to place correctly the bars into the concrete

Several kilometers o f tunnel have been excavated to extend a metropolitan underground system. In some places, where the subsurface is mainly composed by gravel and sands, water can easly penetrate causing problems to the tunnel and the stations. In order to avoid such problems, a jet-grouting injection was carried out. To check the continuity of the jet-grouting a Ground Penetrating Radar analysis was applied. The radar used is a SIR 10 of Geophysical Survey Systems Inc., with a center frecuency antenna of 100 Mz, prepared for urban jobs. A good determination of the variantion of the thickness of the jet-grouting layer was obtained, although several difficulties, specially the irregular topography, were to be solved. Three boreholes to determine the quality and thickness of the jet-grouting in three different places provided the right calibration of the involved radargrams. During the processing of the data, several filters had to be applied to discriminate the radar signals from noise, coming mainly from the electrical system of the tunnel