6 research outputs found
Shape Metamorphosis – Automatic 3D Mesh Generation, Topology Verification and Analysis
The objective of this paper is a 3D shape construction that benefits from discrete and continuous modelling approaches. The proposed solution addresses the problem of automated modelling of virtual structures such as caves, buildings and clouds and presents an alternative solution in the form of a hybrid system. Parallel realizations of these solutions are tested on various processors of graphic cards with the use of NVIDIA ‘CUDA’ technology. This paper describes the implementation of algorithms (approaches) and their parallel speedup, efficiency, throughput. Modelled structures are geometrically complex, with an inner graph structure more optimized than in the classical CSG approach. Moreover, they can be rendered up to very high levels of visual realism. In this paper we mainly focus on the description of the algorithm. We also propose very useful measures that can be used to verify the model geometry
Referencyjne wartości grubości cieśni tarczycy u dzieci w wieku przedpokwitaniowym zamieszkujacych region nadmorski
The study presented the reference values for thyroid isthmus thickness in prepubertal healthy children. Ultrasound evaluation of the isthmus seems to be very useful in the diagnostic process and monitoring of thyroid diseases, especially the diffuse ones. The authors are not aware of the existence of any other publications on reference values of isthmus depth in children population. In our study, we evaluated isthmus thickness in a healthy population of prepubertal children from a seaside region. A total of 402 healthy children (214 boys and 188 girls) aged 7-12 years, underwent ultrasound examinations of the thyroid. We propose the following maximum values for isthmus depth: from 2.6 mm for boys at the age of 7-9 years to 3.3 mm for those aged 10-12 years and from 2.7 mm to 3.5 mm for girls, respectively
Insights into Kidney Dysplasia in Duplex Kidneys: From Radiologic Diagnosis to Histopathologic Understanding
Duplex kidney is a urinary tract anomaly commonly associated with a wide range of primary and secondary parenchymal structural abnormalities. We present a unique comparison of US and MRI findings with histopathology following partial resection of duplex kidneys due to nephropathy. We examined a group of 21 children with duplex kidneys who were qualified for heminephrectomy (24 kidney units (KU)). All patients underwent US and MRI prior to the surgery. The imaging results were compared with histopathologic findings. In 21/24 KU, dysplastic changes were found on histopathology, including all with obstructive nephropathy and 7/10 specimens with refluxing uropathy. The loss of corticomedullary differentiation on US and increased signal on T2-weighted images (T2WI) on MRI were the imaging findings that best correlated with fibrosis. In children with megaureter, there were no statistical differences in histopathological findings between primary megaureter, megaureter with ureterocele, and megaureter with ectopia (p > 0.05). The extent of dysplasia of the affected pole correlated negatively with residual function in MRI. Kidney dysplasia and inflammation in the kidney with obstructive nephropathy are the most important histopathologic findings of this study. US is a valuable screening tool, and MRI enables morphologic and functional assessments of the nephropathy in duplex kidneys
Geophysical Research of Secondary Deformations in the Post Mining Area of the Glaciotectonic Muskau Arch Geopark—Preliminary Results
Underground and opencast mining adversely affects the surrounding environment. This process may continue even decades after the end of actual mineral extraction. One of the most significant effects of ceased mining are secondary deformations. Safe, new development of post-mining areas requires reliable information on potential deformation risk zones, which may be difficult to obtain due to a lack of necessary data. This study aimed to investigate and understand the secondary deformation processes in the underground mining area of the former “Babina” lignite mine, located in the unique glaciotectonic environment of the Muskau Arch, in western Poland. A combination of GIS-based historical mapping, geophysical 2D/3D microgravimetry, and Electrical Resistivity Tomography (ERT) measurements allowed the identification of subsidence-prone areas and the determination of potential factors of sinkhole development. The latter are associated with anthropogenic transformation of rock mass and hydrogeological conditions, by shallow underground mining. The results confirmed that multi-level mining of coal deposits in complex and complicated glaciotectonic conditions cause discontinuous deformations, and may be hazardous as long as 50 years after the end of mining operations