• Title/Summary/Keyword: leak index

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Endotoxin-induced Acute Lung Injury is Mediated by PAF Produced via Remodelling of Lyso PAF in the Lungs

  • Lee, Young-Man;Kim, Teo-An
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.219-226
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    • 2000
  • In order to elucidate the role of platelet activating factor (PAF) in the acute lung injury induced by endotoxin (ETX), activities of phospholipase A2, lyso PAF acetyltransferase and oxidative stress by neutrophilic respiratory burst were probed in the present study. To induce acute lung injury, $100\;{\mu}g$ of E.coli ETX (type 0127; B8) was instilled directly into the tracheae of Sprague-Dawley rats. Five hours after the ETX instillation, induction of acute lung injury was confirmed by lung leak index and protein contents in the bronchoalveolar lavage (BAL) fluid. At the same time, lung phospholipase A2 (PLA2) activity and expression of group I and II secretory type PLA2 were examined. In these acutely injured rats, ketotifen fumarate, known as lyso PAF acetyltransferase inhibitor and mepacrine were administered to examine the role of PAF in the pathogenesis of the acute lung injury. To know the effect of the ETX in the synthesis of the PAF in the lungs, lyso PAF acetyltransferase activity and PAF content in the lungs were measured after treatments of ETX, ketotifen fumarate and mepacrine. In addition, the role of neutrophils causing the oxidative stress after ETX was examined by measuring lung myeloperoxidase (MPO) and enumerating neutrophils in the BAL fluid. To confirm the oxidative stress in the lungs, pulmonary contents of malondialdehyde (MDA) were measured. After instillation of the ETX in the lungs, lung leak index increased dramatically (p<0.001), whereas mepacrine and ketotifen decreased the lung leak index significantly (p<0.001). Lung PLA2 activity also increased (p<0.001) after ETX treatment compared with control, which was reversed by mepacrine and ketotifen (p<0.001). In the examination of expression of group I and II secretory PLA2, mRNA synthesis of the group II PLA2 was enhanced by ETX treatment, whereas ketotifen and WEB 2086, the PAF receptor antagonist, decreased the expression. The activity of the lysoPAF acetyltransferase increased (p<0.001) after treatment of ETX, which implies the increased synthesis of PAF by the remodelling of lysoPAF in the lungs. Consequently, the contents of the PAF in the lungs were increased by ETX compared with control (p<0.001), while mepacrine (p<0.001) and ketotifen (p<0.01) decreased the synthesis of the PAF in the lungs of ETX treated rats. The infiltration of the neutrophils was confirmed by measuring and enumerating lung MPO and the neutrophils in the BAL fluid respectively. Compared with control, ETX increased lung MPO and number of neutrophils in BAL significantly (p<0.001) whereas mepacrine and ketotifen decrerased number of neutrophils (p<0.001) and MPO (p<0.05, p<0.001, respectively). The lung MDA contents were also increased (p<0.001) by ETX treatment, but treatment with mepacrine (p<0.001) and ketotifen (p<0.01) decreased the lung MDA contents. Collectively, we conclude that ETX increases PLA2 activity, and that the subsequently increased production of PAF was ensued by the remodelling of the lyso PAF resulting in tissue injury by means of oxidative stress in the lungs.

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Intraoperative Cerebrospinal Fluid Leak in Extradural Spinal Tumor Surgery

  • Ropper, Alexander E.;Huang, Kevin T.;Ho, Allen L.;Wong, Judith M.;Nalbach, Stephen V.;Chi, John H.
    • Neurospine
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    • v.15 no.4
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    • pp.338-347
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    • 2018
  • Objective: Patients with extradural spine tumors are at an increased risk for intraoperative cerebrospinal fluid (CSF) leaks and postoperative wound dehiscence due to radiotherapy and other comorbidities related to systemic cancer treatment. In this case series, we discuss our experience with the management of intraoperative durotomies and wound closure strategies for this complex surgical patient population. Methods: We reviewed our recent single-center experience with spine surgery for primarily extradural tumors, with attention to intraoperative durotomy occurrence and postoperative wound-related complications. Results: A total of 105 patients underwent tumor resection and spinal reconstruction with instrumented fusion for a multitude of pathologies. Twelve of the 105 patients (11.4%) reviewed had intraoperative durotomies. Of these, 3 underwent reoperation for a delayed complication, including 1 epidural hematoma, 1 retained drain, and 1 wound infection. Of the 93 uncomplicated index operations, there were a total of 9 reoperations: 2 for epidural hematoma, 3 for wound infection, 2 for wound dehiscence, and 2 for recurrent primary disease. One patient was readmitted for a delayed spinal fluid leak. The average length of stay for patients with and without intraoperative durotomy was 7.3 and 5.9 days, respectively, with a nonsignificant trend for an increased length of stay in the durotomy cases (p=0.098). Conclusion: Surgery for extradural tumor resections can be complicated by CSF leaks due to the proximity of the tumor to the dura. When encountered, a variety of strategies may be employed to minimize subsequent morbidity.

Design of gas-gap thermal switch for reducing cooldown time of 2-stage cryocooler (2단 냉동기의 냉각시간 단축을 위한 기체-간극 열스위치 설계)

  • 김형진;장호명
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2000.02a
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    • pp.35-38
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    • 2000
  • A preliminary design of gas-gp thermal switch is presented to reduce the cooldown time of superconducting system conduction-cooled by a two-stage refrigerator without liquid cryogens. The switch connects thermally the first and the second stages (ON) to take advantage of the larger refrigeration capacity at the first stage during the beginning period. After the cryogenic temperature is reached, the switch should isolate thermally the two stages (OFF) in order to reduce the heat leak to the cold end. In this paper, a new concept for the performance index is introduced to evaluate the reduction of the cooldown time and the increase of the cooling load at the same time. In addition, the design of a gas-gap switch is discussed as a closed container of several staggered concentric tubes filled with gas, which is frozen at low temperatures for the shut-off of heat without any mechanical actuation. Some of the detailed features in the design is quantitative investigated by the gas convection model in the continuum or the rarefied gas region.

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Adaptation Policy of ISO 27001 ISMS (Information Security Management System) for e-Government (전자정부 정보보호관리체계(G-ISMS) 적용 정책)

  • Han, Keun-Hee
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.19 no.5
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    • pp.119-130
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    • 2009
  • Korea ranked 2nd in the UN Global e-Participation Index and ranked number one as the leader in e-Government for the third consecutive year. However, Korea ranked 51 in the level of information security published by WEF(World Economic Forum), relatively a low level comparing with its great number of users and excellent environments for the Internet service. A series of critical hacking accidents such as the information leak at Auction and GS Caltex emerged consecutively in 2008 year, resulting in the leak of personal & critical information. This led to a strong interest in the necessity and importance of information security and personal information so that demand for IT security is growing fast. In this paper, we survey to benchmark information security in the perspective of service level, system, investment and policy about major foreign countries. Then we research on an effective way to make the most of the benchmark result to Korea e-Government. In addition, the purpose of this paper is to improve national information security index by developing a policy for ISO 27001 ISMS, an international standard for Information Security Management System, and elevate safety and security of the e-Government serviced by central administrative organizations and local authorities.

Risk Assessment and Its Application for the POSCO's Batch Annealing Furnace Gas Systems (광양제철소 소둔로 가스설비에 대한 위험성 평가 및 안전성향상안 제시)

  • Kim Y. S.;Yoo J. H.;Jeong S. Y.;Jang E. J.
    • Journal of the Korean Institute of Gas
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    • v.5 no.2 s.14
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    • pp.9-13
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    • 2001
  • A complete spectrum of risk assessment including qualitative and quantitative approaches were performed for the POSCO's Batch Annealing Furnace (BAF) gas systems. The purpose of BAF is to enhance the quality of steel by annealing it with either hydrogen/nitrogen mixture gas or pure hydrogen gas. Number of gas leak scenarios were identified to generate frequency of their occurrences. With the hypothetical accident scenarios given, fire/explosion impact studies were performed to estimate magnitude of significant consequences. Several different indices were also presented from which practical safety improvement action items could be established.

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Development of In-tank Pressure Regulator and Solenoid Valve (내장형 레귤레이터 및 솔레노이드 개발)

  • Lee, Jun-Hyuk;Lim, Tae-Hoo;Kim, Kyung-Nam;Shim, Sang-Hak
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.188-191
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    • 2007
  • This paper shows the Development of In-tank pressure regulator and Solenoid Valve used in FCV(Fuel Cell Vehicle). We have developed new type of Regulator and Solenoid through analysis of the structure and characteristics of component of FCS(Fuel Cell System) from the advanced technology. Now it is possible to localize the component by making use of the development of Regulator and Solenoid made by us. Regulator and Solenoid is a equipment to control hydrogen pressure supplied into a stack. Therefore, outlet pressure, a flow of fluid and temperature are important parameters according to a inlet pressure. And leak test, endurance test and burst test should be done to guarantee the performance and safety of Regulator and Solenoid used in the fuel of high pressure. Also, Hydrogen friendly materials are applied to inner parts of the Regulator, Solenoid and weight reduction is done to cost saving in part not related to performance. As a result, we have proven the good performance and reliability in endurance of Regulator, Solenoid and will make an development in performance as well as durability to ensure industrialization.

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Enhanced Stabilization of Carcasses by Retrofitting Burial Sites to Bioreactor (매몰지 생물반응조 개조를 통한 사체의 안정화 촉진)

  • Kim, Geonha;Jeon, Haeseong
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.10
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    • pp.679-684
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    • 2014
  • Many burial sites were constructed to suppress the spread of foot and mouth disease during outbreak. Defected burial sites were removed when leachate leak is presumed and carcasses were moved to the circular storage tanks. However, carcasses were not decomposed possibly due to low water content, low microbial activities, and poor mixing. In this research, storage tank containing carcasses in it was modified to bioreactor to accelerate stabilization. Liquids with nutrients were added and circulated to maintain the optimum water content while extraneous microorganisms were augmented. Settlement was used as the primary index for assessing stabilization rate, and the consolidation theory was utilized to estimate the expected final settlement. 30% of carcasses is expected to be decomposed and removed from the storage tank for five years of bioreactor operation.

KEY IMPACT PARAMETERS FOR APPLICATION OF ALTERNATIVE SOURCE TERM TO KORI UNIT 1

  • Lee, Seung-Chan
    • Nuclear Engineering and Technology
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    • v.42 no.4
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    • pp.394-413
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    • 2010
  • The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of AST under a LOCA, and about 60% greater than that of AST for the case of a LRA; thus the safety margin is remarkably increased when the AST is used. In this work, the sensitivity analysis results are presented in terms of a sensitivity index called the "NDD (Normalized Dose Difference)", which compares the impact of parameters with that of a reference case. These values are derived by using a combination of the leak rate (primary to secondary), iodine chemical form, gap fraction, partitioning factor, spray removal rate, source term, and other variables.

Incidence and Risk Factors for Surgical Glove Perforation (수술용 장갑의 천공률에 대한 연구)

  • Yoo, Seon Ju;Lim, Young Shin;Kim, Myung Suk
    • Journal of Korean Clinical Nursing Research
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    • v.16 no.3
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    • pp.63-71
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    • 2010
  • Purpose: This study was conducted to evaluate the incidence and risk factors for surgical glove perforation during operation. Methods: During the month of december 2008, a total of 1,400 pairs of surgical gloves used in major operations was collected in a tertiary hospital. All gloves were examined immediately after operation using the standardized water-leak method to detect any perforation. Incidence of the glove perforation was counted according to the type of operation, operation time, the number of involved personnel, perforation sites, and the manufacturing companies. Results: Out of 2,800 gloves examined, 312 perforations were detected comprising 11.1% of samples. In terms of the type of operation, the perforation incidence varied from 5% to 20%, and the perforation rates in CS (20%) and NS (18%) (p<.001) were significantly higher than those in other departments. The 1st assistant or scrub nurse got glove perforation more frequently than the 2nd assistant or operator (p<.001). Longer operation time was associated with higher incidence of perforation evidently (p<.001). In terms of the sites, the thumb and index finger were more frequently perforated than other sites (4.1% and 3.4% respectively) without any differences between left and right side. Conclusion: Risk factors for glove perforation including the department of operation, operation time, participating personnel, and location of perforation should be taken into account to improve surgical safety.

Predictors of outcomes after the trans-obturator tape procedure in females with equal severity for stress and urge mixed urinary incontinence

  • Young-Joo Kim
    • Journal of Medicine and Life Science
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    • v.20 no.4
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    • pp.166-171
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    • 2023
  • Mixed urinary incontinence (UI) is common in women. This study aimed to assess the efficacy of anti-incontinence surgery in female patients with equally severe stress UI (SUI) and urge UI (UUI). All patients had equal severity of SUI and UUI. The postoperative cure rate was categorized into the cure group (CG) and failure group (FG). Postoperative satisfaction was categorized into the satisfaction group (SG) and the dissatisfaction group (DG). Statistical significance was set at P<0.05. Ninety patients (SG, 73.3%; DG, 26.7%; CG, 93.3%; FG, 6.7%) were included in the study. In the univariate analysis, body mass index (BMI), total bladder capacity, and overactive bladder symptom score (OABSS) were significantly different between the SG and DG groups. Peak urinary flow, Valsalva leak point pressure (VLPP), and OABSS were significantly different between the CG and FG groups. In the multivariate analysis, OABSS (P=0.001) and BMI (P=0.032) were independent predictors of postoperative satisfaction. VLPP (P=0.023) was the only independent factor associated with the postoperative cure rate. In equal severity of SUI and UUI, VLPP was found to be the only independent factor associated with postoperative cure rates. Higher VLPP values were associated with higher cure rates. BMI and OABSS were identified as independent predictors of postoperative satisfaction, with lower BMI and OABSS associated with higher postoperative satisfaction.