The Comparison of the Results of Ultrasound, CT and MRI in the Diagnosis of Angiomyolipoma Kidneys, Including Complicated by Development of the Syndrome Wunderlich

Purpose: Analysis the effectiveness of various methods of radiation studies for the detection of renal angiomyolipomas (RAMLs), including the diagnosis of Wunderlich syndrome. Material and methods: The analysis of the results of a comprehensive radiation study of the kidneys of 115 patients who were diagnosed with focal formation in primary renal ultrasound was carried out. Further, of those 115 people, 47 patients underwent MRI of the kidneys, 60 patients – CT and 8 patients complex MRI+CT, including contrast-enhanced vasculature. Results and discussion: Angiomyolipoma was detected by ultrasound in 38 (33.0 %) of 115 patients, and according to MRI and CT in total in 27 (23.5 %) patients. Coincidence of ultrasound findings and MRI and CT results was in 18 patients. Consequently, the sensitivity of ultrasound in the diagnosis of RAML was compared with MRI – 45 %; when compared with CT – 42.8 %, and specificity – 55 % and 57.1 %, respectively. Reliable signs of RAML in ultrasound were hyperechogenic homogeneous structure, clear smooth contours of the formation. The rounded form of education is statistically unreliable. Statistically significant characteristics of RAML in magnetic resonance imaging are heterogeneous structure, heterogeneous hyperintense MR-signal on T1 and heterogeneously hypointensity on T2-weighted images, always uniformly hypo-Fs for T1 / T2 Fs, with hypo clear boundary between education and renal parenchyma on T1 in the opp phase. Reliable signs of RAML with CT are non-uniform structure of education, with non-uniform x-ray density. Conclusion: Ultrasound diagnosis is necessary for screening kidney disease, while CT and MRI have greater sensitivity and specificity to determine the nature of focal formation. With the development of Wunderlich’s syndrome, a complex of radiological methods, including ultrasound, MRI and CT, allows to diagnose the cause of hemorrhage, as well as to obtain complete diagnostic information necessary for the surgeon to plan treatment.

Quantitative Computed Tomography, modern data. Review

In the review we discussed about the method of quantitative computed tomography (QCT, quantitative computed tomography). In QCT, X-ray density (HU) is converted to bone mineral density (BMD mg / ml) using linear relationships obtained by scanning calibration standards (phantoms). When compared with the normative age data, it is possible to diagnose osteoporosis (OP). The review presents various QCT techniques and their diagnostic capabilities in accordance with the positions of ISCD 2019 - (International Society for Clinical Densitometry). The results of comparison of QCT and conventional dual-energy X-ray absorptiometry (DXA) are considered. It is noted that in the study of the proximal femur (PF), the results of the methods are well comparable, according to the results of both methods, it is possible to diagnose OP by the T-score. However, when examining the spine QCT, the volume BMD of the trabecular bone of the vertebral bodies is assessed, and with DXA, the projection BMD is assessed. The approaches to the interpretation of the results are also different - diagnosis of OP in DXA of the spine based on the T-score, but in QCT, the ACR (American College of Radiology) criteria are used.We describe the phantoms used in QCT, as well as provide data on radiation exposure during QCT and DXA.The article describes an approach to opportunistic screening of osteoporosis by the QCT based on the results of previously performed CT scans, including its automated work-flow using artificial intelligence technologies. These promising techniques are attractive due to the large number of CT examinations performed and the exclusion of additional examinations.

The low cosmic-ray density in the Polaris Flare

We reported the γ-ray observation towards the giant molecular cloud Polaris Flare. Together with the dust column density map, we derived the cosmic ray (CR) density and spectrum in this cloud. Compared with the CR measured locally, the CR density in the Polaris Flare is significantly lower and the spectrum is softer. Such a different CR spectrum reveals either a rather large gradient of CR distribution in the direction perpendicular to the Galactic plane or a suppression of CR inside molecular clouds.

Diode Laser Lithotription Technique Based on Optothermal Converter

Purpose: evaluation of the efficiency of the “hot spot” method for the fragmentation of urinary stones. Materials and methods: A retrospective analysis of clinical records of 1666 patients with urolithiasis who underwent percutaneous nephrolithoextraction/tripsy and contact ureterolithotripsy/extraction in the period from 2014 to 2017 at the urology clinic was performed to assess the incidence of postoperative infectious and inflammatory complications. The research objects were postoperative urinary stones (n-78). The X-ray density and linear dimensions of the stones were determined. Stone fragmentation was performed with a continuous-wave diode laser operating at wavelengths of 0.81 μm, 0.97 μm, and 1.47 μm. An absorbing coating of micro-size graphite powder was applied on the working tip of the optical fiber. In vitro fragmentation was carried out in liquid. Results: A group of patients (224/1666) (13.4 ± 0.86%) was identified, who developed infectious and inflammatory complications after: percutaneous nephrolithotripsy, 123/361 (34.1 ± 2.5%) cases; percutaneous nephrolithoextraction, 59/240 (24.6 ± 2.78%); contact ureterolithotripsy, 23/294 (7.8 ± 1.57%); and ureterolithoextraction, 19/771 (2.5 ± 0.56%). In liquid, the “hot spot” technique made it possible to fragment stones with an X-ray density of up to 1000 HU at a laser wavelength of 0.81 µm, up to 1400 HU at 0.97 µm, and up to 1400 HU at 1.47 µm.

Synthesis and Characterization of Ce3+-Doped Ni0.5Cd0.5Fe2O4 Nanoparticles by Sol–Gel Auto-Combustion Method

Cerium (Ce)-doped Ni0.5Cd0.5CexFe2−xO4 (0.0 ≤ x ≤ 0.20) was synthesized using the sol–gel auto-combustion method. X-ray diffraction (XRD) analysis revealed that all the samples retained spinel cubic crystal structure with space group Fd3m at 800 °C. Crystal structure parameters, such as lattice constant, average crystallite size, and X-ray density were estimated from the major XRD (311) peak. Bulk density and porosity were also calculated. The average crystallite size was estimated to be in the range of 20–24 nm. SEM images displayed agglomerated particles with a porous morphology. The dielectric constant (ε′) increased and the dielectric loss tangent (tanδ) decreased with rising Ce concentration. The hysteresis loop (M–H loop) was measured at room temperature using a vibrating-sample magnetometer (VSM), which showed a nonlinear decrease in magnetization and coercivity with increasing Ce concentration.

Influence of zinc substitution on structural, elastic, magnetic and optical properties of cobalt chromium ferrites

The polycrystalline Co1−xZnxCr0.5Fe1.5O4 series with (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) has been synthesized by conventional ceramic rout method. The structural and elastic properties have been investigated by X-ray diffractometer and Fourier transform spectroscopy. Both XRD and FTIR confirm the formation of single phase cubic spinel ferrites. The cationic distribution for all samples has been proposed. The lattice parameter, X-ray density, hoping length, bond length, and packing factors–in accompaniment with variations in the zinc concentration–have been studied. The IR band position has been explained by the cations involved in the structure. The elastic moduli such as Young's modulus, bulk modulus, rigidity modulus and Poison's ratio have bee calculated using force constants. Scanning electron microscope (SEM) observation conveys information about the agglomeration of particles. The hysteresis curve obtained from vibrating sample magneto meter (VSM) conveys information about the soft nature of prepared compositions. The saturation magnetization decreases with addition of zinc ions and coercivity is almost zero. An increase in band gap energy has been observed with addition of zinc by Ultraviolet Visible Spectroscopy (UV-VIS), which is due to small crystallite size.

PATHOGENETIC ASPECTS OF THE DEVELOPMENT OF UROLITHIASIS IN KIDNEY TRANSPLANT RECIPIENTS

The aim of this study is to investigate the incidence of urolithiasis in kidney transplant recipients and evaluate the potential of using minimally invasive treatment techniques for these patients. Patients underwent ultrasound examination of the transplanted kidney and urinary tract during regular screening. When a concretion was found, multispiral computed tomography was additionally performed to clarify the size, location, and X-ray density of the concretion. We did not perform contrast enhancement to avoid acute kidney damage to the graft. Additionally, all patients underwent a comprehensive examination with the evaluation of clinical tests of blood, urine, biochemical blood analysis (including creatinine, urea, phosphorus, magnesium, calcium, parathyroid hormone). The patients with a stone of up to 5 mm in diameter and X-ray density below 1000 HU were prescribed dynamic follow-up and litholytic therapy. Contact ureterolithotripsy was performed in the patients with stones of more than 6 mm in diameter. We studied the mineral composition of stones after lithotripsy using infrared spectroscopy. According to the results obtained, the detection rate of urolithiasis in kidney transplant recipients was 7.8%. The patients with graft and urinary tract stones showed a significant increase in the level of parathyroid hormone and blood calcium, leukocyturia of varying severity compared to the patients without urolithiasis. After performing contact ureterolithotripsy, the "stone free" state was achieved in all patients and confirmed by a control ultrasound examination on the fifth day after lithotripsy. Infrared spectroscopy of the removed stone fragments demonstrated their mixed mineral composition, the dominant component of which was calcium phosphate. The data obtained point out the possible pathogenetic factors of the formation of urinary stones in kidney transplant recipients are hyperparathyroidism and the resulting hypocalcaemia, as well as urinary tract infection. Contact lithotripsy should be considered as the method of first choice in this group of patients.

Structural and Dielectric Properties of Calcium Bismuth Titanate (CaBi4Ti4O15) Ceramics

Calcium Bismuth Titanate (CaBi4Ti4O15) ceramics were prepared by conventional solid-state reaction method. X-ray diffraction patterns confirms the orthorhombic structure of CaBi4Ti4O15 and the lattice parameters were also determined. Bulk densities of the sintered ceramics were measured by the Archimedes method with xylene as the liquid media and found to be 97~98% of X-ray density. The surface morphology of CaBi4Ti4O15 is studied by Scanning Electron Microscope (SEM) attached with energy dispersive X-ray spectroscopy (EDS) inorder to determine the grain size as well as the chemical composition of CaBi4Ti4O15. The dielectric constant (k) and dielectric tangent loss (tan δ) of CaBi4Ti4O15 as a function of temperature were measured in the frequency range of 100 Hz-100 KHz. The dielectric constant, dielectric loss and ac conductivity of CaBi4Ti4O15 increases gradually with an increase in the temperature from 303 to 573 K. The ac conductivity of the prepared sample reveals that the conduction mechanism is electronic hoping

Image-guided raytracing and its applications

Eikonal solvers have found important applications in seismic data processing and in-version, the so-called image-guided methods. To this day in image-guided applications, thesolution of the eikonal equation is implemented using partial-differential-equationsolvers, such as fast-marching or fast-sweeping methods. We show that alternatively, onecan numerically integrate the dynamic Hamiltonian system defined by the image-guidedeikonal equation and reconstruct the solution with image-guided rays. We present interest-ing applications of image-guided raytracing to seismic data processing, demonstrating theuse of the resulting rays in image-guided interpolation and smoothing, well-log interpola-tion, image flattening, and residual-moveout picking. Some of these applications make useof properties of the raytracing system that are not directly obtained by eikonal solvers, suchas ray position, ray density, wavefront curvature, and ray curvature. These ray propertiesopen space for a different set of applications of the image-guided eikonal equation, beyondthe original motivation of accelerating the construction of minimum distance tables. Westress that image-guided raytracing is an embarrassingly parallel problem, which makes itsimplementation highly efficient on massively parallel platforms. Image-guided raytracing isadvantageous for most applications involving the tracking of seismic events and imaging-guided interpolation. Our numerical experiments using synthetic and real data sets showthe efficiency and robustness of image-guided rays for the selected applications.

Improved three-dimensional image of the tomographic inversion of the Arraiolos aftershock sequence.

<p><span>This work puts in light the several steps followed to obtain a 3D velocity model in Arraiolos, a region located in central Portugal. After the earthquake of January 2018 occurred, a set of stations were deployed around the main shock area and has recorded the aftershock sequence during a period of six months. </span></p><p><span>The first stage of this study used a set of data recorded along the 1</span><span><sup>st</sup></span><span> month by 21 temporary seismological stations. 317 aftershocks were used to invert a 3D P and S<span>  </span>velocity model, using LOTOS program, and showing an agglomeration of events in one local point leading to a poor resolution. Therefore, we added more stations and data to the second stage of study by integrating 437 aftershocks recorded during a period of 6 months by a set of 34 stations. The tomographic inversion of this extended aftershock sequence has shown a significant improvement of the 3D velocity model resolution and suggesting an alignment of the seismic events cluster. However, the imaged crustal volume was still too small and possessing low resolution on the edges of the area. To fix this issue, additional data and seismological stations were integrated to the study in order to increase the area of interest and cover it entirely in terms of ray density. </span></p><p><span>The step which we are currently conducting concerns the location of new events followed by their integration to the tomographic study using IPMA and DOCTAR station network records. Since the later phases PmP and SmS has the potential to increase the ray coverage as similarly as the resolution of an area, we will hopefully obtain, after their integration, significant improvements in terms of accuracy and reliability of the crustal image. The main purpose of this new stage of study is to finally provide significant interpretations and figure out precisely the tectonic processes having generated the Arraiolos seismicity. </span></p><p><span>Thanks are due to FCT for the financial support to the ICT project (UID/GEO/04683/2013) with the reference POCI-01- 0145-FEDER-007690, to the IDL project (UIDB/50019/2020 – IDL).</span></p>