A Geant4 simulation code for simulating optical photons in SPECT scintillation detectors

Geant4 is an object oriented toolkit created for the simulation of High-Energy Physics detectors. Geant4 allows an accurate modeling of radiation sources and detector devices, with easy configuration and friendly interface and at the same time with great accuracy in the simulation of physical processes. While most Monte Carlo codes do not allow the simulation of the transport and boundary characteristics for optical photons transport generated by scintillating crystal, Geant4 allows the simulation of the optical photons. In this paper we present an application of the Geant4 program for simulating optical photons in SPECT cameras. We aim to study the light transport within scintillators, photomultiplier tubes and coupling devices. To this end, we simulated a detector based on a scintillator, coupled to a photomultiplier tube through a glass window. We compared simulated results with experimental data and theoretical models, in order to verify the good matching with our simulations. We simulated a pencil beam of 140 keV photons impinging the crystal at different locations. For each condition, we calculated the value of the Pulse Height Centroid and the spread of the charge distribution, as read out by the anode array of the photomultiplier. Finally, the spatial and the energy resolutions of the camera have been estimated by simulated data. In all cases, we found that simulations agree very well with experimental data

A Case of Intra and Extra-vascular Lipoma of the Subclavian Vein

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Bone turnover markers in sheep and goat: a review of the scientific literature

Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.José Arthur de A. Camassa acknowledges to the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil, for his PhD scholarship 202248/2015-1.info:eu-repo/semantics/publishedVersio

HPLC analysis of HbA1c in dried blood spot samples (DBS): a reliable future for diabetes monitoring

To simplify collection and transport of blood for HbA1c measuring, we have studied the use of a special paper that absorbs a defined volume of capillary blood and quickly dries it (dried blood-spot, DBS). The DBS can be sent to a central laboratory using regular postal service and without temperature control. This system differs greatly from other proposed DBS methods for HbA1c because it overcomes the haemoglobin alterations during the drying and storing processes, that otherwise make this analysis unreliable. We have developed a special treatment of the paper before collection that stabilises the HbA1c molecule excellently in dried blood samples, allowing accurate HPLC analysis even two weeks after collection. This method has been applied in a "blind" study in which HbA1c values determined in 97 DBS coming from an hospital diabetes care centre were compared with those obtained from parallel venous blood samples

Attivazione di un ambulatorio di continuit\ue0 assistenziale per l\u2019et\ue0 pediatrica. L\u2019esperienza di Verona

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