68 research outputs found
Detailed radiological study of the patent ductus arteriosus: a computed tomography study in the Polish population
Background: The aim of the study was to perform qualitative and quantitative computed tomography (CT) angiography-based evaluation of patent ductus arteriosus (PDA) morphology and its influence on morphology of the great vessels.
Materials and methods: Two-thousand twenty-two patients underwent 64-slice or dual-source CT and were retrospectively screened for the presence of PDA. Those who had presence of PDA underwent evaluation of its anatomy and morphology.
Results: Thirty-two adult patients with PDA were evaluated (mean age 41.4 ± 17.4 years). Subjects with PDA had a higher value of aortic isthmus (p = 0.0148), main pulmonary artery (p < 0.0001), right (p =0.0007) and left (p = 0.0074) pulmonary arteries diameters than individuals from control group (16 adults, median age 43.3 ± 12.4 years). Types A, B, C, D, and E of PDA morphology occurred in 16 (50%), 3 (9%), 9 (28%), 2 (6%), and 2 (6%) patients, respectively. Subjects with the type A configuration of PDA tended to have a larger diameter at the aortic orifice (10.2 ± 5.2 mm vs. 6.4 ± 4.9 mm, p = 0.09) and a larger maximal diameter (10.3 ± 5.3 mm vs. 7.1 ± 4.7 mm, p = 0.14) compared to subjects with the type C configuration. The values of minimal, mean, and maximal diameters of PDA were 4.7 ± 1.9 mm, 7.0 ± 3.2 mm, and 9.4 ± 5.0 mm, respectively. The Spearman correlation coefficient between the main pulmonary artery and PDA diameters demonstrated a good correlation for minimal (r = 0.70, p < 0.001), mean (r = 0.62, p = 001), and maximal (r = 0.60, p = 0.0003) PDA diameters.
Conclusions: Computed tomography enables quantitative and qualitative evaluation of PDA, including its type of morphology, length, and diameters. In the evaluated adult population with PDA, the majority of patients had dilation of the aortic isthmus and pulmonary arteries. PDA diameters correlate with diameters of the pulmonary arteries and this correlation is strongest between PDA diameter at the narrowest site and main pulmonary artery
Computed tomography in the evaluation of the anomalous origin of the coronary artery: coexistence with other congenital heart disease in an adult population
Background: The aim of the study is to assess the prevalence of anomalous origin of the coronary artery in cardiac computed tomography (CT) and to evaluate its coexistence with other congenital heart disease. Materials and methods: 7,115 patients, who underwent 64-slice or dual source cardiac CT in the years 2005–2011 were screened for the presence of anomalous origin of the coronary artery. Results: Anomalous origin of coronary artery was found in 62 (0.87%) patients (34 males, mean age 57.4 ± 15.1 years). Anomalous aortic and pulmonary origin of coronary artery concerned 59 (0.83%) and 3 (0.04%) cases, respectively. Concomitant heart defects were observed in 5 (0.07%) patients, all with anomalous aortic origin of coronary artery. Malformations included transposition of great arteries (4 patients) and single ventricle in (1 patient). Conclusions: The incidence of anomalous origin of a coronary artery in cardiac CT is similar to invasive coronary angiography. In an adult population the vast majority of those anomalies are isolated abnormalities without concomitant other congenital heart defects
Cosmic Ray Extremely Distributed Observatory: a global network of detectors to probe contemporary physics mysteries
In the past few years, cosmic-rays beyond the GZK cut-off ( eV) have been detected by leading collaborations such as Pierre Auger
Observatory. Such observations raise many questions as to how such energies can
be reached and what source can possibly produce them. Although at lower
energies, mechanisms such as Fermi acceleration in supernovae front shocks seem
to be favored, top-down scenarios have been proposed to explain the existence
of ultra-high energy cosmic-rays: the decay of super-massive long-lived
particles produced in the early Universe may yield to a flux of ultra-high
energy photons. Such photons might be presently generating so called
super-preshowers, an extended cosmic-ray shower with a spatial distribution
that can be as wide as the Earth diameter. The Cosmic Ray Extremely Distributed
Observatory (CREDO) mission is to find such events by means of a network of
detectors spread around the globe. CREDO's strategy is to connect existing
detectors and create a worldwide network of cosmic-ray observatories. Moreover,
citizen-science constitutes an important pillar of our approach. By helping our
algorithms to recognize detection patterns and by using smartphones as
individual cosmic-ray detectors, non-scientists can participate in scientific
discoveries and help unravel some of the deepest mysteries in physics.Comment: excited QCD Conference, CREDO Collaboration, 7 pages, 3 figure
Effect of Addition Ce on Crystallisation Kinetics and Structure of Zn-Al-Cu Alloys
The main goal of the presented work was to determine the relationship between changes in the shape of the derivative curve
and the microstructure of Zn-Al-Cu alloys before and after modification. To describe the phenomena that occur in the material
during solidification as a result of the modification in the chemical composition, the thermal-derivative analysis method was applied. This method allows to describe and interpret the kinetics of crystallisation of the tested alloys. To describe the morph
ology
and phase composition, light and electron microscopy (SEM, TEM) was also used.
The modification of the hypereutectic Zn-Al-Cu alloys with the addition of Ce causes a reduction in the size
α'
+
η
eutectics
and change in the morphology of the α'
phase precipitates from dendritic to “tweed”
Biogenic deposites of the Eemian Interglacial at Porzewnica and Marysin near Minsk Mazowiecki (Wegrów Basin-Central Poland)
Ice sheet of the Wartanian Glaciation and their deposits shaped the landscape of the Węgrów Basin. Biogenic lake sediments at Porzewnica and Marysin sites (figs.1, 2) consist of about 5 m thick silts and gyttja, covered by 1.15 m thick sand at Porzewnica and by 8.5 m thick silts and sands at Marysin. In the Porzewnica pollen diagram (fig. 4) there are 7 L PAZ and 1 interzone without sporomorphs. representing vegetation succession during the late Wartanian Glaciation, the protocratic, mesocratic and part of the telocratic phases of the Eemian Interglacial. Spectra of sediments at the Marysin site represent 4 L PAZ of the youngest part of the mesocratic phase and fragments of the telocratic phase of that Interglacial
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