• Investigative Magnetic Resonance Imaging
• /
• v.21 no.3
• /
• pp.192-194
• /
• 2017

Giant arachnoid granulations have been reported to be associated with headaches, which can be acute or chronic in presentation. In some cases, idiopathic intracranial hypertension, previously called pseudotumor cerebri, may occur. The pathophysiology of these enlarged structures seen as filling defects on imaging is not clearly defined, although they are presumed to cause symptoms such as headache via pressure resulting from secondary venous sinus obstruction. We present a unique presentation of secondary headache in a 39-year-old man with no prior history of headaches found to have giant arachnoid granulations, presenting as migraine with aura.

• Environmental Analysis Health and Toxicology
• /
• v.14 no.1_2
• /
• pp.65-73
• /
• 1999

Dioxins refer to a family of chemicals comprising 75 polychlorinated dibenzo-p-dioxin (PCDD) and 135 polychlorinated dibenzo-p-furan (PCDF) congeners, which may cause skin disorder, human immune system disruption, birth defects, severe hormonal imbalance, and cancer. The effects of exposure of dioxin-like compounds such as PCBs are mediated by binding to the aryl hydrocarbon receptor (AHR), which is a ligand-activated transcription factor. To grasp physicochemical factors affecting human toxicity of dioxins, six geometrical and topological indices, eleven thermodynamic variables, and quantum mechanical descriptors including ESP (electrostatic potential) were analyzed using QSAR and semi-empirical AM1 method. Planar dioxins with high lipophilicity and large surface tension show the probability that negative electrostatic potential in the lateral oxygen may make hydrogen bonding with DNA bases to be a carcinogen.

• Journal of Chest Surgery
• /
• v.23 no.6
• /
• pp.1174-1179
• /
• 1990

Forty-five patients with double-outlet right ventricle[DORV] underwent complete intracardiac repair between July, 1983 and June, 1989. Patients with complete atrioventricular canal, atrioventricular discordance and uni-ventricular heart were excluded. The 32 male and 13 female patients ranged in age from 3 months to 15 years[mean 4 years]. Thirty-two patients had pulmonary stenosis. The early mortality was 11.ltd[5 /45] None of 27 died after a completely intraventricular repair. The mortality was 20%[1/5] for repair using transannular patch, 20% [1/5] for REV operation, 33.3%[1/3] for repair including extracardiac valved conduit, and 50% [1/2] for Jatene operation, respectively. Two modified Fontan procedures were performed without mortality. One died after Senning operation. Causes of early deaths included high residual right ventricular pressure[one patient] small left atrial and left ventricular volume[one patient], persisting severe pulmonary hypertension [one patient] and low cardiac output of unknown cause [two patients]. Complete heart block developed in one patient. Two late deaths occurred among the 40 operative survivors [5.0Po] from persisting severe pulmonary hypertension and bleeding at reoperation. Our results indicate that significant defects can be repaired with low mortality and morbidity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.15 no.2
• /
• pp.147-152
• /
• 2002

Carbon nitride thin films were deposited by reactive sputtering for the hard coating materials on Si wafer and tool steels. When the nitrogen content of carbon nitride film on tool steel is 33.4%, the mean hardness and elastic modulus are 49.34 GPa and 307.2 GPa respectively. The nitrided or carburised surface acts as the diffusion barrier which shows better adhesion of carbon nitride thin film on the steel surface. To prevent nitrogen diffusion from the film, steel substrate can be saturated by nitrogen forming a Fe$_3$N layer. The desirable structure at the surface after carburising is martensite, but sometimes, due to high carbon content an proeutectoid Fe$_3$C structure may form at the grain boundaries, leaving the overall surface brittle and may cause defects.

• International Journal of Railway
• /
• v.5 no.2
• /
• pp.84-88
• /
• 2012

Derailment due to wheel failure would cause a tremendous social and economical cost in service operation. It is necessary to evaluate quantitatively the safety with respect to high-speed train. Although the safety of railway wheel has been ensured by an regular inspection, all critical defects cannot be detected in inspection cycles and the wheel has been replaced because a defect quickly become critical for safety. Therefore, it is important to calculate quantitatively the fracture limit and remnant life of damaged railway wheel in wheel-rail system. In present paper, the critical crack size of wheel for high-speed train is simulated based on fracture scenario and the safety of wheel is evaluated.

• IE interfaces
• /
• v.20 no.1
• /
• pp.87-93
• /
• 2007

Burn-in is an engineering method for screening out products containing reliability defects which would cause early failures in field operation. Previously, various burn-in models have been proposed mainly focused on the trade-off of shop repair cost and warranty cost ignoring manufacturing yield. From the view point of a manufacturer, however, burn-in decreases warranty cost at the expense of yield reduction. In this paper, we provide a general model quantifying a trade-off between product yield and reliability, in which any defect distribution from previous yield models can be used. A profit function is expressed in burn-in environments for determining an optimal burn-in time. Finally, the method is illustrated with gate oxide failures which is an important reliability concerns for VLSI CMOS circuits.

• Journal of Chest Surgery
• /
• v.47 no.3
• /
• pp.310-312
• /
• 2014

When the juvenile worms of the genus Paragonimus migrate and cause defects on the surface of the visceral pleura, pneumothorax can develop. A 34-year-old woman was admitted for pneumothorax with which was developed after she ate raw fish and crab. A 21-year-old male soldier presented with recurrent bilateral pneumothorax without eosinophilia, caused after drinking stream water frequently. In both patients, paragonimiasis was suspected from the computed tomography scan and confirmed by an enzyme-linked immunosorbent assay test of the pleural fluid. When pneumothorax develops in patients who have ingested raw fresh-water crab or stream water, paragonimiasis should always be considered in the differential diagnosis.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.30 no.3
• /
• pp.271-281
• /
• 2010

Brazing fitting which is one of the aircraft hydraulic power system components is widely used for saving weight and achieving higher reliability. Any inherent defects or damage of fitting can cause system failure and/or physical damage of human body due to highly pressurized fluid. Radiographic testing(RT) technique and additional micro-structure investigation on cut-away surfaces have been accomplished to find out some defect-like-inhomogeneity in the fittings. The radiography results showed that some defect-like-inhomogeneity existed inside body. Additional micro-structure investigation on cut-away surface reveals that the inhomogeneity is due to internal voids. In this study, it can be is said that RT technique can be a useful tool for field acceptance test of hydraulic brazing fitting in short time.

• Childhood Kidney Diseases
• /
• v.27 no.1
• /
• pp.19-25
• /
• 2023

Proteinuria is an important risk factor for renal and cardiovascular disease. It is associated with a risk for glomerulonephritis, chronic kidney disease, and end-stage renal disease. Therefore, if persistent proteinuria is detected, kidney biopsy is considered to diagnose and treat the underlying disease. Recently, variants in the cubilin (CUBN) gene, which is associated with albuminuria, have been reported. This gene encodes cubilin, a membrane glycoprotein receptor expressed in the renal proximal tubules. Cubilin is a component of the megalin and cubilin-amnionless complex that mediates albumin reabsorption into the proximal tubules through endocytosis. A defect in cubilin leads to a reduction in albumin reuptake, resulting in albumin-dominant proteinuria. Although numerous controversies exist, several reports suggest that cubilin defects lead to proteinuria with a high portion of albuminuria but may not impair renal filtration function. If albuminuria due to reduced cubilin function is confirmed as a benign condition, we can consider using genetic studies to detect CUBN mutations in patients with proteinuria and they may not require any treatment or kidney biopsy. Here, we review recent papers on CUBN mutations and discuss the prognosis and management of individuals with this mutation.

• Corrosion Science and Technology
• /
• v.6 no.4
• /
• pp.193-197
• /
• 2007

It is well known that the development of Advanced High Strength Steels (AHSS) is very important for the automotive industry in order to improve fuel efficiency and the reduction of material costs. However, it is particularly difficult to improve the surface quality of AHSS because the high amount of Si, Al, Mn and Ti etc. in AHSS promote selective oxidation, resulting in surface defects. The reheating process in the hot strip mill would cause severe oxidation because it is carried out at elevated temperatures under aggressive environments. In this study a reheating furnace simulator was developed to investigate oxidation phenomena in the reheating process. The environmental gas for the reheating furnace was made by burning coke oven gas with air in the simulator. The air/fuel ratio is precisely controlled by MFC. Ti oxides are easily formed on grain boundaries and Mn and Si oxides are usually formed in inner grains near the steel surface with a small round shape.