Comparison of low-dose contrast computed tomography angiography findings with surgical results in living kidney donors

Aim: To analyze the image quality and diagnostic performance of CT angiography using low dose (60 ml) contrast medium for living kidney donors and compare with surgical results. Material and Method: Angiographic findings of 81 renal donor Candidates in 128-slice MDCT were evaluated by two independent radiologists in terms of renal artery number, early bifurcation, renal vein variations, pelvicalyceal system and ureter variations. Results were compared with intraoperative findings. The image quality, diagnostic performance and interobserver agreement of MDCT obtained with low dose contrast material were analyzed. Results: The mean age of the 81 living kidney donors included in the study was 49±12 (24-68) years. Left nephrectomy was performed in 71% (n=64) and right nephrectomy in 29% (n=17) of the donors. Intraoperative accessory arteries were detected in 22.2% (n:18) of the donors. The specificity, sensitivity, and accuracy for detecting accessory artery variation in MDCT were 100%, 88.9%, and 97.5%, respectively. Early bifurcation was observed in 21% (n=17) of the donors. Specificity, sensitivity and accuracy for early bifurcation detection were 98.4%, 94.1% and 97.5%, respectively. Renal vein variation was detected in 12.3% (n=10) of the donors. Specificity, sensitivity, and accuracy for renal vein variation detection were 100%. Variations of the pelvicalyceal system and ureter were observed in 3.7% (n=3) of the donors. The specificity, sensitivity, and accuracy for detecting pelvicalyceal system and ureteral variations were 100%. Interobserver agreement was excellent in detecting variations of accessory arteries, renal venous anomalies, pelvicalyceal system and ureters by MDCT (kappa: 1,000; p< 0.001). It was higher in early bifurcation detection (kappa: 0.853; p< 0.001). Conclusion: MDCT angiography with a lower dose of iodine contrast at 60 mL in kidney donors is sufficient to detect vascular anomalies and provide anatomical information. It is possible to reduce the contrast agent dose in CTA without affecting the preoperative evaluation

A case of urinary tract infection caused by Raoultella planticola after a urodynamic study

AbstractHere we report the case of a patient who developed urinary tract infection after a urodynamic study. The causative agent was Raoultella planticola, a rare opportunistic pathogen that usually invades immunocompromised patients. While a urinary tract infection with R. planticola has been previously described, this is the first report in which an R. planticola infection developed after a urodynamic study. We postulate that the mechanism of infection was direct invasion of the urinary tract from contaminated urodynamic study equipment. Here, we discuss the role played by isotonic solutions in facilitating bacterial reproduction

An aggressive aneurysmal bone cyst of the proximal humerus and related complications in a pediatric patient

Clinical behavior of aneurysmal bone cyst (ABC) in younger patients can be more aggressive than that in older children and adults. Angular deformity and shortening can occur due to growth plate destruction or tumor resection. A 11-year-old boy who had been operated twice in another center for an ABC located in the left proximal humerus presented to the author’s institution with complaints of pain, deformity and shortening of the left arm. Plain radiographs revealed left proximal humerus nonunion with a large defect. Reconstruction with nonvascularized fibular autograft was applied and left upper extremity was immobilized in a velpou bandage. At the third-month follow-up, graft incorporation was observed in the distal part; however, proximal part did not show adequate healing on radiographs. Additional immobilization in a sling for 3 months was advised to the patient and his family. However, they were lost to follow-up and readmitted to the author’s institution at the 12th month postoperatively. Radiographs showed failure of the fibular graft fixation and nonunion of the humerus. Autogenic bone grafts, either vascularized or nonvascularized are the best treatment method for the large defects after tumor curettage or resection. Nonvascularized grafts are technically much easier to use than vascularized grafts and provide excellent structural bone support at the recipient side. However, they may take several months to be fully incorporated. In addition, good therapeutic outcomes require patience and collaboration with the patient and parents. Most importantly, the patient should be monitored closely

Maximizing Minimum Pressure in Fluid Dynamic Bearings of Hard Disk Drives

We focus on the central spindle which supports the rotating magnetic platters which hold all of the data. The spindle must operate with great precision and stability at high rotational speeds. Design practice has converged on oil-lubricated hydrodynamic journal bearings as the most common choice for spindles. That is, a layer of viscous oil separates a rotating shaft (the bearing) from the fixed outer sleeve (the journal). In hard drives, it is very important for the shaft to be centered within the sleeve. Plain journal bearings (i.e. both surfaces are circular cylinders) are unstable to perturbations that push the shaft off-center. It was found that this stability problem can be overcome by cutting diagonal grooves into the journal in a pattern called a herring-bone. Another consequence of this design is that very high pressures are generated by the grooves as they drive the oil to the middle of the bearing, away from the top/bottom ends of the spindle. This pumping action generally works to oppose leakage out of the bearing. We examine how choices for the groove pattern can influence the key properties of the bearing. The focus is to understand the effect of the groove geometry on the pumping action. In particular the undesirable behavior caused by the low pressures created near the top/bottom ends of the bearing which, under many conditions, may result in the pressure becoming negative, relative to atmospheric pressure. Negative pressure can result in cavitation or, when it occurs near an air-oil interface, can cause air to be ingested and hence create bubbles. Any bubbles in the oil can corrupt the lubricating layer in the bearing and, as they are created and collapse, can cause significant undesirable vibrations. The negative pressures have therefore been identified as one of the key problems in design of hard disk drive bearings. We will use numerical computations and some analysis to show that by modifying the groove geometry we can reduce the negative pressure while retaining good stability characteristics

The eROSITA Final Equatorial-Depth Survey (eFEDS): A machine learning approach to inferring galaxy cluster masses from eROSITA X-ray images

We have developed a neural network-based pipeline to estimate masses of galaxy clusters with a known redshift directly from photon information in X-rays. Our neural networks were trained using supervised learning on simulations of eROSITA observations, focusing on the Final Equatorial Depth Survey (eFEDS). We used convolutional neural networks that have been modified to include additional information on the cluster, in particular, its redshift. In contrast to existing works, we utilized simulations that include background and point sources to develop a tool that is directly applicable to observational eROSITA data for an extended mass range – from group size halos to massive clusters with masses in between 10$^{13}$ M < M < 10$^{15}$ M . Using this method, we are able to provide, for the first time, neural network mass estimations for the observed eFEDS cluster sample from Spectrum-Roentgen-Gamma/eROSITA observations and we find a consistent performance with weak-lensing calibrated masses. In this measurement, we did not use weak- lensing information and we only used previous cluster mass information, which was used to calibrate the cluster properties in the simulations. When compared to the simulated data, we observe a reduced scatter with respect to luminosity and count rate based scaling relations. We also comment on the application for other upcoming eROSITA All-Sky Survey observations

The eROSITA view of the Abell 3391/95 field: The Northern Clump. The largest infalling structure in the longest known gas filament observed with eROSITA, XMM-Newton, and Chandra

SRG/eROSITA PV observations revealed the A3391/95 cluster system and the Northern Clump (MCXC J0621.7-5242 galaxy cluster) are aligning along a cosmic filament in soft X-rays, similarly to what has been seen in simulations before. We aim to understand the dynamical state of the Northern Clump as it enters the atmosphere ($3\times R_{200}$) of A3391. We analyzed joint eROSITA, XMM-Newton, and Chandra observations to probe the morphological, thermal, and chemical properties of the Northern Clump from its center out to a radius of 988 kpc ($R_{200}$). We utilized the ASKAP/EMU radio data, DECam optical image, and Planck y-map to study the influence of the WAT radio source on the Northern Clump central ICM. From the Magneticum simulation, we identified an analog of the A3391/95 system along with an infalling group resembling the Northern Clump. The Northern Clump is a WCC cluster centered on a WAT radio galaxy. The gas temperature over $0.2-0.5R_{500}$ is $k_BT_{500}=1.99\pm0.04$ keV. We employed the $M-T$ scaling relation and obtained a mass estimate of $M_{500}=(7.68\pm0.43)\times10^{13}M_{\odot}$ and $R_{500}=(636\pm12)$ kpc. Its atmosphere has a boxy shape and deviates from spherical symmetry. We identify a southern surface brightness edge, likely caused by subsonic motion relative to the filament gas. At $\sim\! R_{500}$, the southern atmosphere appears to be 42% hotter than its northern atmosphere. We detect a downstream tail pointing toward the north with a projected length of $\sim318$ kpc, plausibly the result of ram pressure stripping. The analog group in the Magneticum simulation is experiencing changes in its gas properties and a shift between the position of the halo center and that of the bound gas, while approaching the main cluster pair.Comment: 24 pages, 17 figures (main text), 6 figures (appendix). Submitted to A&A for the Special Issue: The Early Data Release of eROSITA and Mikhail Pavlinsky ART-XC on the SRG Mission. For more information, see https://astro.uni-bonn.de/~averonica/NorthernClump/eROSITA_A3391_Northern_Clump_AIfA.htm

Laboratuvardan Kliniğe Transplantasyon Pratiği

Transplantasyon; Temel Tıbbi Bilimler, Moleküler Tıp, Genetik ve İmmünolojiden klinik uygulamalardan destek alan multidisipliner bir tıp dalıdır. Temel bilimlerdeki başarılı çalışmaların kliniğe uygulanması, klinikte karşılaşılan sorunların da, oluşturulan deneysel hayvan modellerinde irdelenmesi, elde edilen bilgilerin klinik uygulamalara aktarılması; diğer deyişle tecrübelerin “Translational” özellikli olması günümüz transplantasyon çalışmalarında bir gerekliliktir. İmmün sistemin bileşenlerinin ve reaksiyonlarının iyi bilinmesi, hücreler arası ilişkilerde greftin reddi ya da kabul edilmesinin şartlarını doğru anlamak ve uygun laboratuvar yöntemleri ile klinik durumun aydınlatılması transplantasyonda stratejik önemdedir. Bu nedenle, klinik transplantasyon çalışmaları yapanlar temel bilimler bilgileri ile de donanımlı olmalıdırlar. Multidisipliner bir dal olma bilinci ile yapılan klinik transplantasyon çalışmalarında başarı yakalanmaktadır. Laboratuvardan Kliniğe Transplantasyon kitabımızda tüm yönleri ile transplantasyonun organizmaya etkileri ve bunların klinik sonuçlarını, çalışmalarımızın ışığında sunmayı ve tartışmayı hedefledik. Editör: Prof.Dr. Mesut İzzet TİTİZ Yardımcı Editör: Doç.Dr. Pınar AT

The Capacity of the Evaluation of Linguistic Abilities of FLE Examinations Applied in Turkey by OSYM

: Since the ultimate object of the assessment and the evaluation in foreign language is the communication competence, it remains custom to determine the parameters and the performance criteria of the foreign language users. However, the multiple choice items used in Turkey generally do not allow us to measure different types of learners such as oral communication. It is limited only to the measurement of mental processes such as knowledge comprehension and application. En the contrary, the multiple choice items are still mostly preferred. Within the framework of this research, our aim is to analyze the multiple choice tests prepared and applied in Turkey by the OSYM in various examinations such as the OSS, the KPDS and the UDS

Intrauterine lower extremity gangrene in a newborn with tetralogy of fallot

DESCRIPTION: Intrauterine gangrene of an extremity is a rare problem. Lower extremity gangrene is even rarer. We present a case of lower extremity gangrene in combination with Tetralogy of Fallot (TOF) and postaxial polydactyly of the hand. A live male infant was delivered by caesarean section. Delivery occurred at the 34th week of gestation due to meconium aspiration and intrauterine growth retardation