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The aim of this paper is to characterize two HPGe gamma-ray detectors used in two different laboratories for environmental radioactivity measurements, so as to perform efficiency calibrations by means of Monte Carlo Simulation. To achieve such an aim, methodologies developed in previous papers have been applied, based on the automatic optimization of the model of detector, so that the differences between computational and reference FEPEs are minimized. In this work, such reference FEPEs have been obtained experimentally from several measurements of the IAEA RGU-1 reference material for specific source-detector arrangements. The models of both detectors built through these methodologies have been validated by comparing with experimental results for several reference materials and different measurement geometries, showing deviations below 10% in most cases. [ABSTRACT FROM AUTHOR]

In this work, we have developed a computational methodology for characterizing HPGe detectors by implementing in parallel a multi-objective evolutionary algorithm, together with a Monte Carlo simulation code. The evolutionary algorithm is used for searching the geometrical parameters of a model of detector by minimizing the differences between the efficiencies calculated by Monte Carlo simulation and two reference sets of Full Energy Peak Efficiencies (FEPEs) corresponding to two given sample geometries, a beaker of small diameter laid over the detector window and a beaker of large capacity which wrap the detector. This methodology is a generalization of a previously published work, which was limited to beakers placed over the window of the detector with a diameter equal or smaller than the crystal diameter, so that the crystal mount cap (which surround the lateral surface of the crystal), was not considered in the detector model. The generalization has been accomplished not only by including such a mount cap in the model, but also using multi-objective optimization instead of mono-objective, with the aim of building a model sufficiently accurate for a wider variety of beakers commonly used for the measurement of environmental samples by gamma spectrometry, like for instance, Marinellis, Petris, or any other beaker with a diameter larger than the crystal diameter, for which part of the detected radiation have to pass through the mount cap. The proposed methodology has been applied to an HPGe XtRa detector, providing a model of detector which has been successfully verificated for different source-detector geometries and materials and experimentally validated using CRMs. [ABSTRACT FROM AUTHOR]

The determination in a sample of the activity concentration of a specific radionuclide by gamma spectrometry needs to know the full energy peak efficiency (FEPE) for the energy of interest. The difficulties related to the experimental calibration make it advisable to have alternative methods for FEPE determination, such as the simulation of the transport of photons in the crystal by the Monte Carlo method, which requires an accurate knowledge of the characteristics and geometry of the detector. The characterization process is mainly carried out by Canberra Industries Inc. using proprietary techniques and methodologies developed by that company. It is a costly procedure (due to shipping and to the cost of the process itself) and for some research laboratories an alternative in situ procedure can be very useful. The main goal of this paper is to find an alternative to this costly characterization process, by establishing a method for optimizing the parameters of characterizing the detector, through a computational procedure which could be reproduced at a standard research lab. This method consists in the determination of the detector geometric parameters by using Monte Carlo simulation in parallel with an optimization process, based on evolutionary algorithms, starting from a set of reference FEPEs determined experimentally or computationally. The proposed method has proven to be effective and simple to implement. It provides a set of characterization parameters which it has been successfully validated for different source-detector geometries, and also for a wide range of environmental samples and certified materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: Congenital perineal lipoma is extremely rare and may lead to a misdiagnosis of ambiguous genitalia. CASE REPORTS: We report on two girls referred to our service for ambiguous genitalia. Patient 1 (17 days old) and patient 2 (2 months old) had unremarkable gestational and perinatal histories. Both had normal female external genitalia and a 46,XX karyotype. Patient 1 had a polypoid, protruding 3.0???2.0???1.5-cm phallic-like mass arising at the inferior border of the left labium majora, and patient 2 had a similar mass of 1.5???1.5???1.0?cm at the same site and an imperforate anus. In both cases the mass was removed and found to be a lipoma. DISCUSSION: To our knowledge, perineal lipoma has been reported only in eleven girls, nine of them with associated anorectal malformation. Migration and fusion of the labioscrotal folds and formation of the urorectal septum are simultaneous developmental events occurring in the same region, which may explain the association of perineal lipoma and anorectal malformations. [ABSTRACT FROM AUTHOR]

Abstract??Osteochondroma is one of the most common benign tumors of the axial skeleton. Location of a solitary exostosis in the scapula is relatively rare. We report the case of an osteochondroma of the scapula in a 13-year-old boy. Because of the atypical location with nonspecific shoulder pain, the diagnosis is often made late. CT is necessary to determine the correct position of the osteochondroma. Despite the young age of the patient, surgical excision of the exostosis was performed, because of an arising thoracic pressure pain. The outcome was good, the patient noticed disappearance of previous painful symptoms, and a normal profile of the scapula was gained. [ABSTRACT FROM AUTHOR]

Introduction: Capgras syndrome, where patients have the conviction that one or more close people have been replaced by a "double," is the most prevalent delusional misidentification syndrome. It appears in psychiatric illness and organic brain damage. It seems to be due to damage of bifrontal and right limbic and temporal regions, mainly in the right hemisphere. Objectives: To review the pathologies associated to Capgras Syndrome and the relevance of the differential diagnosis Methods: 53-year-old female was admitted due to great sadness, crying, social withdrawal and severe paranoid concerns over the last month. Follow-up in Mental Health since 2014, because of anxious depression. After her mother's death, she felt being followed because of old faults. Since then, low dosis of antipsychotics were used. Now she is afraid of being harmed in relation to petty thefts she committed over 15 years ago. In recent days, she has been noticing small details indicating that her family members have been impersonated by strangers, showing anguish regarding their whereabouts. Results: During her admission, high doses of antidepresants and paliperidone 6 mg/day were used with the complete disappearance of Capgras Syndrome and her anguish. Mild guilty thoughts were present after her discharge. That is why she was diagnosed with psychotic depression. Conclusions: Capgras syndrome can be encountered in primary psychiatric diagnosis (particularly in schizophrenia and mood disorders) - where an organic element may exist in about a third of all cases - or secondary to organic disorders or medicationinduced, through to overt organic brain damage, particularly in neurodegenerative disease. [ABSTRACT FROM AUTHOR]