A detailed investigation of gamma and neutron shielding capabilities of ternary composites doped with polyacrylonitrile and gadolinium (III) sulfate.

The shielding efficiencies of gamma and neutron radiations for ternary composites containing polyester resin, polyacrylonitrile and gadolinium (III) sulfate at different ratios were investigated in the present study. In order to investigate the gamma radiation shielding capacity of the produced ternary composites, linear and mass attenuation coefficients, half value layer, effective atomic number and radiation protection efficiency parameters were determined experimentally, theoretically and using the GEANT4 simulation code. The gamma shielding capabilities of the composites were studied in the photon energy range of 59.5-1332.5 keV. In order to investigate the neutron shielding abilities of composites, inelastic, elastic, capture and transport numbers, total macroscopic cross section and mean free path parameters were determined with the help of GEANT4 simulation code. In addition, the number of transmitted neutrons at different sample thicknesses and neutron energies were also determined. It was observed that gamma radiation shielding properties were improved due to the increasing amount of gadolinium (III) sulfate and neutron shielding properties were improved due to the increasing amount of polyacrylonitrile. While the composite coded P0Gd50 exhibits a better gamma radiation shielding ability than the others, the neutron shielding of the sample coded P50Gd0 is also more favorable than the others.

A comparative neutron and gamma-ray radiation shielding investigation of molybdenum and boron filled polymer composites.

This work presents a detailed radiation shielding study for polymer composites filled with Boron and Molybdenum additives. The chosen novel polymer composites were produced at different percentages of the additive materials to provide a proper evaluation of their neutron and gamma-ray attenuation abilities. The effect of additive particle size on the shielding characteristics was further investigated. On the gamma-ray side, simulation, theoretical and experimental evaluations were performed in a wide range of photon energies varying from 59.5 keV to 1332.5 keV with help of MC simulations (GEANT4 and FLUKA), WinXCOM code, a High Purity Germanium Detector, respectively. A remarkable consistency was reported between them. On the neutron shielding side, the prepared samples produced with nano and micron particle size additives were additionally examined by providing fast neutron removal cross-section (ΣR) and the simulated neutron transmissions through the prepared samples. The samples filled with nano sized particles show better shielding capability than the one filled with micron sized particles. In other words, a new polymer shielding material that does not contain toxic content is introduced: the sample codded N-B0Mo50 exhibits superior radiation attenuation.

An analysis of lesions associated with developmental venous anomalies.

OBJECTIVE: The aim of this study was to describe different lesions and features associated with developmental venous anomalies (DVAs). METHODS: The records and magnetic resonance imaging (MRI) images of 1,722 patients who underwent cranial MRI between 2010 and 2017 were retrospectively reviewed. It was found that 124 (7.2%) patients had DVAs, and 48 of these patients (38.7%) had additional anomalies accompanying DVAs. Of the patients with DVAs, 25 were female and 23 were male, with a mean age of 39.3 years (range, 3-77 years). MRI was performed in all the patients. RESULTS: In addition to DVAs, cavernomas were present in 30 patients (62.5%), haematomas in 7 (14.5%), gliosis in 6 (12.5%), demyelinating plaques in 4 (8.3%) and a glioblastoma in 1 (2.2%). The mean diameter of the DVAs was 1.1mm and the mean diameter of the lesions was 17.4mm. The susceptibility weighted imaging (SWI) sequence was also applied to 12 patients with cavernomas. The relevant sequence in all of these patients contributed to the diagnosis. CONCLUSION: Our study shows that DVAs can accompany a wide spectrum of lesions, especially cavernomas. Although their pathophysiology has not yet been clearly established, these lesions may have a common aetiology.

Sinonasal teratocarcinosarcoma mimicking chronic invasive fungal disease of paranasal sinuses.

Sinonasal teratoid carcinosarcoma or teratocarcinoma is an extremely rare aggressive tumour. It usually arises in the nasal cavity and paranasal sinuses. In this study, the authors described magnetic resonance imaging and computed tomography findings from a patient with sinonasal teratocarcinoma. Computed tomography of the sinonasal teratoid carcinosarcoma can mimic paranasal fungal infections. Magnetic resonance imaging is a very useful tool for making a differential diagnosis between the sinonasal teratoid carcinosarcoma and paranasal sinusitis.

Magnetic resonance imaging demonstration of an unusual triplication anomaly of the inferior vena cava.

Knowing congenital anomalies of the inferior vena cava is of clinical importance for radiological interventional procedures and retroperitoneal surgery. We present magnetic resonance imaging of the coincidence of fenestrated right and left inferior vena cava anomalies in a 78-year-old woman. Contrast-enhanced magnetic resonance imaging is an important imaging technique that is preferred in evaluating vascular structures in this locality.

Determination of anomalous pulmonary venous return with high-pitch low-dose computed tomography in paediatric patients.

BACKGROUND: In this study, we aimed to image pulmonary venous return anomalies and associated cardiovascular and pulmonary abnormalities by high-pitch low-dose computed tomography (CT) in children. MATERIALS AND METHODS: Forty-one patients with total or partial anomalous pulmonary venous return anomalous between May 2012 and June 2019 were retrospectively reviewed. The anomalies were determined using high-pitch low-dose CT. The patients' mean age was 3 years (6 months to 15 years), and 24 of them were female. RESULTS: There were 10 patients with total pulmonary venous return anomalies (TPVRA) and 31 patients with partial pulmonary venous return anomalies (PPVRA). Six (60%) patients with TPVRA had the supracardiac type, 2 (20%) had the cardiac type, and 2 (20%) had the mixed type. All patients with TPVRA had a large atrial septal defect (ASD), 1 patient also had patent ductus arteriosus, and 1 patient had right cardiac hypertrophy. Forty cases of PPVRA were found in 31 patients. Twenty-seven (67%) of them were right-sided, and 13 were left-sided (33%). Twenty (65%) patients also had an additional cardiovascular anomaly (ASD in 12 patients, persistent superior vena cava in 4 patients, patent ductus arteriosus in 3 patients, and aortic coarctation in 2 patients). Of the 27 patients with right-sided PPVRA, it drained into the superior vena cava in 19 patients, the right atrium in 5 patients, and the inferior vena cava in 3 patients. In left-sided cases, the anomalous pulmonary vein drained into the left innominate vein in 9 patients, and in 4 patients, there were accessory pulmonary veins that drained into the left innominate vein. Many of the patients had additional lung anomalies, including pneumonic infiltration (n = 12), atelectasis (n = 8), and lobar emphysema (n = 5), and some of these findings coexisted. CONCLUSIONS: Anomalous pulmonary venous drains and associated cardiac and extra-cardiac anomalies can be detected reliably and quickly with high-pitch low-dose CT without sedation in paediatric patients.

Esplenosis peritoneal múltiple simulando una metástasis mesentérica en una mujer con carcinoma mamario / Multiple peritoneal splenosis mimicking mesenteric metastases in a woman with breast carcinoma

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Tumefactive perivascular space demonstrated with post-contrast time-of-flight MR angiography.

The cerebral perivascular spaces are interstitial fluid-filled anatomic structures surrounding the perforating arteries. They appear as small, round or curvilinear structures on magnetic resonance (MR) imaging. Occasionally, these structures may become very large and cause mass effect. In this case, they may imitate malignant processes and are referred to as tumefactive perivascular spaces. In this study, we present a case of tumefactive perivascular space demonstrated with post-contrast time-of-flight (TOF) MR angiography. To our knowledge, there have been no previous clear demonstrations of the perforating artery in tumefactive perivascular space with contrast-enhanced TOF MR angiography. The purpose of this study was to describe advanced imaging findings in this unusual condition.

A rare cause of congenital portosystemic shunt: type 2 Abernethy malformation.

The Abernethy malformation is characterised by congenital extrahepatic portosystemic shunts and is divided into two groups according to the type of anastomosis. In type 1, all portal venous blood is discharged into the inferior vena cava and there is no intrahepatic portal vein. In type 2, the portal vein is partially discharged to the inferior vena cava via side-by-side anastomoses. Imaging has an important role in the diagnosis and follow-up of this malformation. Magnetic resonance imaging should be preferred to demonstrate both vessel anatomy and associated anomalies. The aim of this study was to present a 17-year-old male patient and to discuss the imaging findings of Abernethy malformation.

Giant cell reparative granuloma of the mandible with an aggressive radiological appearance.

Giant cell reparative granuloma is an unusual benign process arising especially in the maxillofacial bones. It occurs in the second and third decades, predominantly in children and young adults, and is classified as peripheral (located in gingival tissues) and central (located in bone). We presented an unusual case with a lytic and aggressive radiological appearance.