• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.7
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• pp.7-14
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• 2009

In this paper, the effects of annealing conditions on the structural ((002) intensity, FWHM, d-spacing, grain size, (002) peak position), optical (UV peak, UV peak position) and electrical properties (carrier concentrations, resistivity, mobility) of ZnO films were investigated. ZnO films were deposited onto SiO$_2$/si substrates by RF magnetron sputtering from a ZnO target. The substrate was not heated during deposition. ZnO films were annealed in temperature ranges of $500\sim650^{\circ}C$ in the O$_2$ flow for 5$\sim$20 min. The film average thicknesses were in the range of 291 nm. The surface morphologies and structures of the samples were characterize by SEM and XRD, respectively. The optical properties were evaluated by photoluminescence (PL) measurement at room temperature (RT) using a He-Cd 325 nm laser. As the annealing temperature and time vary, the following relations were also observed: (1) proportional relationships among UV intensity (002) intensity, and grain size exist, (2) UV intensity is inversely proportional to FWHM, (3) there is no special relationship between UV intensity and electron carrier concentrations, (4) d-spacing is inversely proportional to (002) peak position, (5) UV peak position in the range of 3.20$\sim$3.24 eV means that ZnO films have a n-type conductivity which was consistent with that obtained from the electrical property, (6) the optimal conditions for the best optical and structural characteristics were found to be oxygen fraction, (O$_2$/(O$_2$+Ar)) of 0.2, RF power of 240W, substrate temperature of RT, annealing condition of 600$^{\circ}C$ for 20 min, and sputtering pressure of 20 mTorr.

• Economic and Environmental Geology
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• v.22 no.3
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• pp.221-235
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• 1989

Gold-silver mineralization of the Goryeong-Waegwan area was deposited in three stages of quartz and calcite veins which fill fissures in Cretaceous sedimentary rocks of the Sindong Group. Radiometric dating indicates that mineralization is Late Cretaceous age(98 Ma) likely associated genetically with intrusion of a small biotite granite stock. Fluid inclusion and stable isotope data indicate that Au-Ag ore was deposited at temperatures between $280^{\circ}C$ and $230^{\circ}C$ from fluids with salinities between 1.7 and 8.7 equiv.wt.% NaCl. Evidence of boiling indicates pressures of <100 bars, corresponding to depths of 425 and 1,150m, respectively, assuming lithostatic and hydrostatic loads. Within ore stage I there is an apparent decrease in ${\delta}^{34}S$ values of $H_2S$ with paragenetic time, from +1.4 to -2.5 per mil. This pattern was likely achieved through progressive increases in pH and activity of oxygen accompanying boiling. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids(${\delta}D$ = -90 to -100 per mil; ${\delta}^{18}O$ = +3.9 to -11.4 per mil) indicate meteoric water dominance, approaching unex-changed meteoric water values. Au-Ag deposition is thought to be the result of cooling and dilution of a boiling fluid through mixing with less evolved meteoric waters.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.639-648
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• 1997

Background : Arterial hypoxemia has been noted in patients with liver cirrhosis because of bronchial vessel dilatation. Cabenes et al. reported that bronchial hyperresponsiveness to the metacholine inhalation was observed in patients of left side heart failure, he suggested that one of the mechanism was bronchial vessel dilatation. We hypothesized that patients of liver cirrhosis might have bronchial hyperresponsiveness to metacholine inhalation due to portal hypertension. We evaluate the relationship between bronchial responsiveness and severity of liver cirrhosis, severity of portal hypertension. Methods : In the 22 patients of the liver cirrhosis with clinical portal hypertension, metacholine provocation test was done and determined $PC_{20}FEV1$. We classified liver cirrhosis according to Pugh-Child classification. Esophagogastroscopies were performed for the evaluation of the relationship between bronchial hyperresponsiveness and severity of esophageal varix. Results : In the 22 cases of the liver cirrhosis with clinical portal hypertension. The causes of liver cirrhosis, alcoholic hepatitis was 9 cases, hepatitis B virus was 12 cases, hepatitis C virus was 1 case, and 151 cases (68.18%) of total 22 cases were positive in metacholine provocation test. In positive cases. There was no significant relationship between $PC_{20}FEV1$ and severity of liver cirrhosis which were classified by Pugh-Child classification or severity of esophageal varix(p<0.05). Conclusion : we observed that bronchial responsiveness to metacholine increased in the patients of liver cirrhosis and there was no significant relationship between the severity of liver cirrhosis and the severity of esophageal varix.

• Tuberculosis and Respiratory Diseases
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• v.48 no.1
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• pp.54-66
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• 2000

Background: Pneumoconiosis, like other chronic respiratory diseases, is essentially incurable and, for many, progressive. While improved survival time is an important aim of treatment, there is growing recognition that for some people, improving the quality of life is more important than extending the length of life. Currently the measurement of the quality of life is used to assess the efficacy of therapeutic agents. Methods: Sixty-three pnemoconiotics who were admitted to St. Mary's Hospital between April and August 1999 were interviewed using COOP charts, Chronic Respiratory Questionnaire(CRQ) and Pneumoconiotic Respiratory Questionnaire(PRQ), a newly developed questionnaire concerning clinical and socioeconomic features of pneumoconiotics. Also, ILO classification of the chest film, pulmonary function test, and arterial blood gas analysis of the patients were evaluated. The scores between Industrial Accident Compensation Insurance(IACI) covered and uncovered patients and between clinically stable and unstable patients were compared. Results: Domains of CRQ and PRQ showed a high internal consistency reliability($\alpha$=0.86-0.89, 0.77-0.81) except the dyspnea domain($\alpha$=0.63) of CRQ. The scores on the CRQ and PRQ showed statistically significant correlations with the results of COOP charts, pulmonary function test and arterial blood gas analysis. The dyspnea domain and social activity domain of the PRQ showed significant difference between IACI covered and uncovered patients and between clinically stable and unstable patients. Conclusion : Korean translation of the Chronic Respiratory Questionnaire and the newly developed Pneumoconiotic Respiratory Questionnaire are reliable and valid methods and are likely to be useful in measuring the quality of life in patients with the chronic respiratory disease including pneumoconiosis.

• Journal of the Korean Geographical Society
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• v.38 no.2
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• pp.184-205
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• 2003

Sustainable Development(SD) is an important concept for the future of the coastal area, and for development of fishing villages. Since 1992 UN Conference on Environment and Development in Rio de Janeiro many governments and local authorities throughout the world have been engaged in preparing and implementing $\ulcorner$Agenda 21$\lrcorner$. Many projects which previously would have been identified as environmental protection are now presented under the banner of sustainable development. Integrated Coastal Management (ICM) is an extension of sustainable development. ICM was presented as a framework for resolution of coastal use conflicts. The aim of the present paper is to assess sustainable development potential of fishing villages in Cheonsu Bay Region according to implementation of ICM. Cheonsu Bay Region was known as one of the productive fishing grounds and Cheonsu Bay Region preserved unique characteristics of traditional fishing villages. But this region is now experiencing many changes through the massive reclamation projects like Seosan A B Project. After a brief overview of concepts and history of SD and ICM, the reclamation process and its impacts on both fishery and fishing communities in Cheonsu Bay Region are discussed. According to their changing environmental and socio-economic characteristics after the reclamation, ca 35 representative coastal villages in this region can be classified into 5 types. Many coastal villages shows diversity in their economic activities, as tourism and recreation function becomes more and more important in this region. In present-day Cheonsu Bay Region, it is possible to differentiate fishing village cooperatives(FVO) with high potential of sustainable fishery development, FVOs with medium potential, FVOs with low potential on the basis of 14 selected indicators.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.452-461
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• 1994

Background: Tumor necrosis factor(TNF)-$\alpha$ and Interleukin(lL)-$1{\beta}$ are thought to play a major role in the pathogenesis of the septic syndrome, which is frequently associated with adult respiratory distress syndrome(ARDS). In spite of many reports for the role of TNF-$\alpha$ in the pathogenesis of ARDS, including human studies, it has been reported that TNF-$\alpha$ is not sensitive and specific marker for impending ARDS. But there is a possibility that the results were affected by the diversity of pathogenetic mechanisms leading to the ARDS because of various underlying disorders of the study group in the previous reports. The purpose of the present study was to evaluate the roles of TNF-$\alpha$ and IL-$1{\beta}$ as a predictable marker for development of ARDS in the patients with septic syndrome, in which the pathogenesis is believed to be mainly cytokine-mediated. Methods: Thirty-six patients of the septic syndrome hospitalized in the intensive care units of the Asan Medical Center were studied. Sixteens suffered from ARDS, whereas the remaining 20 were at the risk of developing ARDS(acute hypoxemic respiratory failure, AHRF). In all patients venous blood samples were collected in heparin-coated tubes at the time of enrollment, at 24 and 72 h thereafter. TNF-$\alpha$ and IL-$1{\beta}$ was measured by an enzyme-linked immunosorbent assay (ELISA). All data are expressed as median with interquartile range. Results: 1) Plama TNF-$\alpha$ levels: Plasma TNF-$\beta$ levels were less than 10pg/mL, which is lowest detection value of the kit used in this study within the range of the $mean{\pm}2SD$, in all of the normal controls, 8 of 16 subjects of ARDS and in 8 in 20 subjects of AHRF. Plasma TNF-$\alpha$ levels from patients with ARDS were 10.26pg/mL(median; <10-16.99pg/mL, interquartile range) and not different from those of patients at AHRF(10.82, <10-20.38pg/mL). There was also no significant difference between pre-ARDS(<10, <10-15.32pg/mL) and ARDS(<10, <10-10.22pg/mL). TNF-$\alpha$ levels were significantly greater in the patients with shock than the patients without shock(12.53pg/mL vs. <10pg/mL) (p<0.01). There was no statistical significance between survivors(<10, <10-12.92pg/mL) and nonsurvivors(11.80, <10-20.8pg/mL) (P=0.28) in the plasma TNF-$\alpha$ levels. 2) Plasma IL-$1{\beta}$ levels: Plasma IL-$1{\beta}$ levels were less than 0.3ng/mL, which is the lowest detection value of the kit used in this study, in one of each patients group. There was no significant difference in IL-$1{\beta}$ levels of the ARDS(2.22, 1.37-8.01ng/mL) and of the AHRF(2.13, 0.83-5.29ng/mL). There was also no significant difference between pre-ARDS(2.53, <0.3-8.34ngfmL) and ARDS(5.35, 0.66-11.51ng/mL), and between patients with septic shock and patients without shock (2.51, 1.28-8.34 vs 1.46, 0.15-2.13ng/mL). Plasma IL-$1{\beta}$ levels were significantly different between survivors(1.37, 0.4-2.36ng/mL) and nonsurvivors(2.84, 1.46-8.34ng/mL). Conclusion: Plasma TNF-$\alpha$ and IL-$1{\beta}$ level are not a predictable marker for development of ARDS. But TNF-$\alpha$ is a marker for shock in septic syndrome. These result could not exclude a possibility of pathophysiologic roles of TNF-$\alpha$ and IL-$1{\beta}$ in acute lung injury because these cytokine could be locally produced and exert its effects within the lungs.

• Journal of Chest Surgery
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• v.37 no.3
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• pp.201-209
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• 2004

Extracorporeal life support (ECLS) system is a device for respiratory and/or heart failure treatment, and there have been many trials for development and clinical application in the world. Currently, a non-pulsatile blood pump is a standard for ECLS system. Although a pulsatile blood pump is advantageous in physiologic aspects, high pressure generated in the circuits and resultant blood cell trauma remain major concerns which make one reluctant to use a pulsatile blood pump in artificial lung circuits containing a membrane oxygenator. The study was designed to evaluate the hypothesis that placement of a pressure-relieving compliance chamber between a pulsatile pump and a membrane oxygenator might reduce the above mentioned side effects while providing physiologic pulsatile blood flow. The study was performed in a canine model of oleic acid induced acute lung injury (N=16). The animals were divided into three groups according to the type of pump used and the presence of the compliance chamber, In group 1, a non-pulsatile centrifugal pump was used as a control (n=6). In group 2 (n=4), a single-pulsatile pump was used. In group 3 (n=6), a single-pulsatile pump equipped with a compliance chamber was used. The experimental model was a partial bypass between the right atrium and the aorta at a pump flow of 1.8∼2 L/min for 2 hours. The observed parameters were focused on hemodynamic changes, intra-circuit pressure, laboratory studies for blood profile, and the effect on blood cell trauma. In hemodynamics, the pulsatile group II & III generated higher arterial pulse pressure (47$\pm$ 10 and 41 $\pm$ 9 mmHg) than the nonpulsatile group 1 (17 $\pm$ 7 mmHg, p<0.001). The intra-circuit pressure at membrane oxygenator were 222 $\pm$ 8 mmHg in group 1, 739 $\pm$ 35 mmHg in group 2, and 470 $\pm$ 17 mmHg in group 3 (p<0.001). At 2 hour bypass, arterial oxygen partial pressures were significantly higher in the pulsatile group 2 & 3 than in the non-pulsatile group 1 (77 $\pm$ 41 mmHg in group 1, 96 $\pm$ 48 mmHg in group 2, and 97 $\pm$ 25 mmHg in group 3: p<0.05). The levels of plasma free hemoglobin which was an indicator of blood cell trauma were lowest in group 1, highest in group 2, and significantly decreased in group 3 (55.7 $\pm$ 43.3, 162.8 $\pm$ 113.6, 82.5 $\pm$ 25.1 mg%, respectively; p<0.05). Other laboratory findings for blood profile were not different. The above results imply that the pulsatile blood pump is beneficial in oxygenation while deleterious in the aspects to high pressure generation in the circuits and blood cell trauma. However, when a pressure-relieving compliance chamber is applied between the pulsatile pump and a membrane oxygenator, it can significantly reduce the high circuit pressure and result in low blood cell trauma.

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.25-43
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• 1997

Introduction : The outcome and incidence of acute respiratory distress syndrome (ARDS) could be variable related to the varied definitions used for ARDS by researchers. The purpose of the national survey was to define the risk factors of ARDS and investigate the prognostic indicies related to mortality of ARDS in Korea according to the definition of ARDS determined by the American-European Concensus Conference on 1992 year. Methods : A Multicenter registry of 48 University or University-affliated hospital and 18 general hospital s equipped with more than 400 patient's beds conducted over 13 months of patients with acute respiratory distress syndrome using the same registry protocol. Results : 1. In the 12 months of the registry, 167 patients were enrolled at the 24 hospitals. 2. The mean age was 56.5 years (${\pm}17.2$ years) and there was a 1.9:1 ratio of males to females. 3. Sepsis was the most common risk factors (78.1%), followed by aspiration (16.6%), trauma (11.6%), and shock (8.5%). 4 The overall mortality rate was 71.9%. The mean duration was 11 days (${\pm}13.1$ days) from the diagnosis of ARDS to the death. Respiratory insufficiency appeared to be a major cause in 43.7% of the deaths followed by sepsis (36.1%), heart failure (7.6%) and hepatic failure (6.7%). 5. There were no significant differences in mortality based on sex or age. No significant difference in mortality in infectious versus noninfectious causes of ARDS was found. 6. There were significant differences in the pulse rate, platelet numbers, serum albumin and glucose levels, the amounts of 24 hour urine, arterial pH, $Pa0_2$, $PaCO_2$, $Sa0_2$, alveolar-arterial oxygen differences, $PaO_2/FIO_2$, and PEEP/$FI0_2$ between the survivors and the deaths on study days 1 through 6 of the first week after enrollment. 7. The survivors had significantly less organ failure and lower APACHE III scores at the time of diagnosis of ARDS (P<0.05). 8. The numbers of organ failure (odd ratio 1.95, 95% confidence intervals:1.05-3.61, P=0.03) and the score of APACHE III (odd ratio 1.59, 95% confidence interval:1.01-2.50, P=0.04) appeared to be independent risk factors of the mortality in the patients with ARDS. Conclusions : The mortality was 71.9% of total 167 patients in this investigation using the definition of American-European Consensus Conference on 1992 year, and the respiratory insufficiency was the leading cause of the death. In addition, the numbers of organ failure and the score of APACHE III at the time of diagnosis of ARDS appeared to be independent risk factors of the mortality in the patients with ARDS.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.619-627
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• 2004

Background : Corticosteroids in combination with cytotoxic drugs are the mainstays of therapy for idiopathic pulmonary fibrosis (IPF). However, there has been no regimen showing any survival benefit. The aim of this study was to describe a short-term clinical experience on interferon gamma-1b (IFN-${\gamma}1b$) therapy for IPF, as an antifibrotic agent. Methods : Medical records of 27 patients who were treated with IFN-${\gamma}1b$ (2 million IU, 3 times a week, subcutaneous injection) were retrospectively reviewed. Treatment response was assessed using ATS/ERS criteria in 17 patients who received IFN-${\gamma}1b$ for more than 6 months. In addition, we compared the efficacy of IFN-${\gamma}1b$ therapy with that of cyclophosphamide${\pm}$prednisolone therapy (n=26). Results : The median age of IFN-${\gamma}$ treated group (M:F=19:8) was 59 years (44-74 years). Compared to the patients who showed a stable response at 6 months (n=12), the deteriorated group (n=5) had worse baseline lung function (FVC, $55.4{\pm}11.3%$ vs. $70.7{\pm}10.9%$, p=0.019; DLco, $50.3{\pm}7.3%$ vs. $76.9{\pm}19.6%$, p=0.014). Lower baseline $PaO_2$ on room air breathing was observed in the deteriorated group ($68.6{\pm}7.8mmHg$ vs. $91.4{\pm}6.6mmHg$ p=0.001). Subcutaneous IFN-${\gamma}1b$ did not show better efficacy than prednisolone. Five patients discontinued IFN-${\gamma}$ because of severe side effects. ARDS developed in one patient, who eventually died. Conclusion : The administration of IFN-${\gamma}1b$ is not desirable for patients diagnosed with IPF with poor lung function. Long-term and large-scaled clinical studies are needed for its efficacy in IPF.

• Neonatal Medicine
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• v.18 no.2
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• pp.328-336
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• 2011

Purpose: An association between very low birth weight infants(VLBWI) and hearing loss has long been recognized. Early identification and intervention for hearing loss benefits language and speech/cognitive development. We investigated the risk factors and clinical outcomes of hearing loss among VLBWI. Methods: We analyzed the results of auditory brainstem response (ABR) testing of VLBWI. These infants were admitted to the neonatal intensive care unit (NICU) of Pusan National University Yangsan Hospital between December 2008 and February 2011. A follow-up was conducted subsequently. Results: ABR evaluations were performed on 65 infants, and 31 showed abnormal results (47.7%). Among the 31 infants, 10 were classified with moderate/severe/profound hearing loss (15.4%). The infants with abnormal ABR had a higher incidence of low birth weight, prolonged ventilator care, cumulative dose of furosemide, and the lowest $PaO_2$ (P<0.05). Those with moderate/severe/profound hearing loss had a higher incidence of low Apgar scores at 5 minutes (odds ratio[OR],0.34; 95% confidence interval[CI],0.13-0.89), prolonged ventilator care (OR,1.06; 95% CI,1.01-1.12), and mild hearing loss compared to those without profound hearing loss. Follow-up evaluations on eight infants with ABR reveled improvements 5.6${\pm}$3.9 months later. One infant, who had profound hearing loss in both ears, used a hearing aid. Conclusion: Factors influencing hearing loss at the first VLBWI hearing screening test included lower Apgar scores at 5 min and prolonged use of a ventilator. Most VLBWI with hearing losses were expected to recover after several months of follow-up.