폐 FRP/Urethane Foam 충진 혼성복합재의 제조 및 기계적 물성에 관한 연구

황택성,신경섭,박진원 공주대학교 자원재활용신소재지역협력센터 2000 2차년도 센터 사업 성과집 Vol.2000 No.1

욕조 생산시 발생하는 폐 FRP와 냉장고 등 가전품과 폐단열재로부터 발생하는 폐우레탄폼을 흡음 및 경량판재로 재활용하기 위하여 불포화 폴리에스테르 매트릭스 수지에 보강하여 복합재를 제조하였다. 또한 충진재의 함량의 변화가 복합재의 기계적 물성에 미치는 영향과 기지와 보강재간의 계면현상을 관찰하였다. 충진제의 함량이 70 wt%인 복합재의 인장강도는 82.34MPa로 가장 우수하였으며, 인장탄성율은 보강재의 함량이 증가함에 따라 감소하였다. 또한 굴곡강도와 굴곡탄성율은 폐FRP의 함량이 70wt% 충진된 복합재가 가장 우수하였으며, 그 값은 각각 72.5, 958.4MPa이었다. SEM 관찰 결과 70 wt% 충진된 충진제 매트릭스 수지의 계면에서 pull out 현상이 확인되지 않았으며 균열도 발생하지 않았고, 매트릭스 수지내에 충진된 폐 FRP/우레탄폼 충진제가 잘 분산되어 있음을 확인할 수 있었다. The waste FRP oocured in the fabrication of SMC (sheet molding campound) bathtubs and the waste polyurethane foam occured in electronic manufacture and waste insulator were applied as a soundproof and light weight pannel in the waste FRP unsaturated polyester matrix resin composites to recycle. The effect of filler contents of the mechanical properties and interfacial phenomena of the filler and matrix on the composites was evaluated. The tensile strength of composites reached its maximum value of 82.34 MPa when the filler content was 70 wt%, and the more content of reinforcement is increased, the more tensile modulus was decreased. The flexural strength and modulus of csomposites, reinforced 70 wt% with filler content, were dominant compared to the other samples to 72.5 Mpa, 958.4 MPa respectively. When composite of reinforced 70 wt% with filler content, it was confirmed that pull out phenomena and cracks did not occur in the interface of reinforcement and matrix resin through the SEM observation. Also, waste FRP and urethane foam were dispersed well into matrix resin as filler.

RAW 264.7 세포에 대한 중국산 천연 광물성 섬유 TAFMAG의 독성효과

임영,한진구,김지홍,김현욱,김은경,김경아,장황신 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.3

Objectives : This study was designed to evaluate cytotoxicity of TAFMAG, which is a trade name of natural mineral fiber mined and produced in China. Methods : The cytotoxicity of TAFMAG was evaluated by measuring iron content, lipid peroxidation, erythrocyte hemolysis, and cytotoxicity in vitro. These results were compared with the data of chrystotile and wollastonite as a positive and negative control, respectively. Results : There was significant increase of Fenton activity in TAFMAG and chrysotile with dose-response pattern. The iron chelating agent, desferrioxamine, significantly decreased Fenton activity of the particulates except wollastonite. TAFMAG and chrysotile fibers significantly increased malondialdehyde concentration from lipid peroxidation of the red blood cell membrane. In erythrocyte hemolysis test, TAFMAG & chrysotile had stronger effect on erythrocyte hemolysis than wollastonite with the concentration of 1,000g/ml. Furthermore, TAFMAG was more hemolytic than chrysotile with the concentration of 5,000g/ml. There was a significant cytotoxic effect in TAFMAG and chrysotile on RAW cell compared with wollastonite. Conclusions : In vitro study suggested that TAFMAG may have a similar health hazard as usual asbestos.

Hepatic outflow obstruction at middle hepatic vein tributaries or inferior right hepatic veins after living donor liver transplantation with modified right lobe graft: comparison of CT and Doppler ultrasound.

Hwang, Hye Jeon,Kim, Kyoung Won,Jeong, Woo Kyoung,Kim, So Yeon,Song, Gi-Won,Hwang, Shin,Lee, Sung-Gyu American Roentgen Ray Society, etc.] 2009 American Journal of Roentgenology Vol.193 No.3

<P>OBJECTIVE: The objective of our study was to compare CT and Doppler ultrasound in the diagnosis of hepatic outflow obstruction at the middle hepatic vein (MHV) tributaries and inferior right hepatic veins (RHVs) after living donor liver transplantation (LDLT) with modified right lobe grafts. MATERIALS AND METHODS: Thirty-seven venographies were performed in 36 patients after LDLT with modified right lobe grafts, evaluating 51 MHV tributaries and 25 inferior RHVs. They were classified as obstructed or nonobstructed. On Doppler ultrasound or CT, flow patterns of the MHV tributaries and inferior RHVs or the relative parenchymal attenuation, enhancement, and opacification of these veins were evaluated for the diagnosis of hepatic outflow obstruction. McNemar tests were performed to compare the diagnostic values of Doppler ultrasound and CT. RESULTS: On the basis of hepatic venography, 33 MHV tributaries were categorized as obstructed and 18 as nonobstructed, and 16 inferior RHVs were categorized as obstructed and nine as nonobstructed. For the diagnosis of MHV tributary obstruction, Doppler ultrasound was more sensitive and accurate, although less specific, than CT (97% vs 39%, respectively, p < 0.001; 86% vs 61%, p = 0.0209; 67% vs 100%, p = 0.0412). Similarly, Doppler ultrasound was more sensitive (94% vs 31%, respectively) and accurate (84% vs 56%) than CT, although less specific (67% vs 100%), for the diagnosis of inferior RHV obstruction, with a statistical significance only for sensitivity (p = 0.002, 0.092, and 0.248, respectively). CONCLUSION: Doppler ultrasound is more sensitive and accurate than CT for the detection of obstruction at the MHV tributaries and inferior RHVs in patients after LDLT using modified right lobe grafts. Although current CT criteria produce high specificity and may reduce unnecessary invasive venographies, optimal CT criteria with acceptable sensitivity should be reestablished.</P>

IMAGE OF INTEREST : Nutmeg liver cardiac cirrhosis caused by constrictive pericarditis

( Kyoung Hwang Shin ),( Hyun Don Joo ),( Il Han Song ) 대한내과학회 2015 The Korean Journal of Internal Medicine Vol.30 No.6

Alcohol and Liver Living Donor Liver Transplantation For Patients With Alcoholic Liver Disease

( Shin Hwang ),( Sung Gyu Lee ),( Chul Soo Ahn ),( Ki Hun Kim ),( Deok Bog Moon ),( Tae Yong Ha ),( Gi Won Song ),( Dong Hwang Jung ),( Je Ho Ryu ),( Jung Ik Park ),( Hyo Jun Lee ),( Kyoung Hoon Ko ) 대한소화기학회 2007 SIDDS Vol.9 No.-

Background/Aims: Since most transplantation studies for alcoholic liver disease (ALD) were performed on deceased donor liver transplantation, little was known following living donor liver transplantation (LDLT). Methods: The clinical outcome of 18 ALD patients who underwent LDLT from Febraury 1997 to December 2004 in a large-volume liver transplantation center was assessed retrospectively. Results: The model for end-stage liver disease score was 23±11, and mean pretransplant abstinence period was 16±13 months, with 14 (77.8%) patients being abstinent for at least 6 months. Graft types were right lobe grafts in 11, left lobe grafts in 2 and dual grafts in 5. Graft to recipient body weight ratio was 0.94±0.16. The relapse rates in patients who did and did not maintain 6 months of abstinence were 7.1% and 50%, respectively (p=0.097). Younger recipient age was a significant risk factor for alcohol relapse (p=0.027). Five recipients with antibody to hepatitis B surface antigen (HBsAg) received core antibody-positive liver graft, but two of them showed positive HBsAg seroconversion. Overall 5-year patient survival rate following LDLT was 87.8%, with a 5-year relapse rate of 16.7%. Conclusions: Pretransplant abstinence for 6 months appears to be benefical for preventing posttransplant relapse. Life-long prophylactic measure should be followed after use of anti-HBc-positive liver grafts regardless of hepatitis B viral marker status of the recipient.

Right hepatic vein stenosis at anastomosis in patients after living donor liver transplantation: optimal Doppler US venous pulsatility index and CT criteria--receiver operating characteristic analysis.

Hwang, Hye Jeon,Kim, Kyoung Won,Jeong, Woo Kyoung,Song, Gi-Won,Ko, Gi-Young,Sung, Kyu Bo,Shin, Yong Moon,Kim, Pyo Nyun,Ha, Tae-Yong,Moon, Deok-Bog,Kim, Ki-Hun,Ahn, Chul-Soo,Hwang, Shin,Lee, Sung-Gyu Radiological Society of North America 2009 Radiology Vol.253 No.2

<P>PURPOSE: To establish optimal Doppler ultrasonographic (US) venous pulsatility index and computed tomographic (CT) criteria for right hepatic vein (RHV) stenosis after living donor liver transplantation (LDLT) and to compare accuracies of these methods by using receiver operating characteristic (ROC) analysis. MATERIALS AND METHODS: This retrospective study was approved by an institutional review board; informed consent was waived. Eighty patients (48 men, 32 women; mean age, 51.5 years +/- 9.2 [standard deviation]) underwent Doppler US and CT within 8 days of hepatic venography following right lobe LDLT between October 2006 and September 2008. At venography, RHVs were classified into a stenosis or nonstenosis group. At Doppler US, venous pulsatility index was defined as the difference between maximum and minimum frequency shifts divided by maximum frequency shift. At CT, diameters of anastomosis and RHV were measured; percentage of stenosis was calculated. Mean Doppler US and CT parameters in the two groups were compared; ROC analysis was performed. RESULTS: There were 30 stenotic and 50 nonstenotic RHVs. Mean venous pulsatility index and mean anastomosis diameter were significantly lower and mean percentage of stenosis was significantly higher in the stenosis than the nonstenosis group (P < .001 each). Optimal cutoffs for venous pulsatility index, anastomosis diameter, and percentage of stenosis were 0.16, 3.7 mm, and 47%, respectively. Sensitivity and specificity were 86.7% and 68.0% for venous pulsatility index, 96.7% and 88.0% for anastomosis diameter, and 96.7% and 86.0% for percentage of stenosis, respectively. At ROC analysis, anastomosis diameter (P = .002) and percentage of stenosis (P = .003) were significantly more accurate than venous pulsatility index. CONCLUSION: CT is more accurate than Doppler US for RHV stenosis after LDLT, with venous pulsatility index as the sole sonographic criterion. Patients suspected of having RHV stenosis at Doppler US may benefit from CT to reduce unnecessary venography.</P>

산업부산물의 치환율에 따른 증기양생 모르타르의 압축강도 특성

신경수 ( Shin Kyoung Su ),황선경 ( Hwang Sun Kyoung ) 한국건축시공학회 2023 한국건축시공학회 학술발표대회 논문집 Vol.23 No.2

This study evaluated the compressive strength characteristics of steam curing mortar according to the substitution rate of industrial by-products, and showed a tendency to increase the compressive strength when gypsum was substituted up to 30%.

Identification of Missing Proteins in Human Olfactory Epithelial Tissue by Liquid Chromatography-Tandem Mass Spectrometry

Hwang, Heeyoun,Jeong, Ji Eun,Lee, Hyun Kyoung,Yun, Ki Na,An, Hyun Joo,Lee, Bonghee,Paik, Young-Ki,Jeong, Tae Seok,Yee, Gi Taek,Kim, Jin Young,Yoo, Jong Shin American Chemical Society 2018 Journal of proteome research Vol.17 No.12

<P>We performed proteomic analyses of human olfactory epithelial tissue to identify missing proteins using liquid chromatography-tandem mass spectrometry. Using a next-generation proteomic pipeline with a < 1.0% false discovery rate at the peptide and protein levels, we identified 3731 proteins, among which five were missing proteins (P0C7M7, P46721, P59826, Q658L1, and Q8N434). We validated the identified missing proteins using the corresponding synthetic peptides. No olfactory receptor (OR) proteins were detected in olfactory tissue, suggesting that detection of ORs would be very difficult. We also identified 49 and 50 alternative splicing variants mapped at the neXtProt and GENCODE databases, respectively, and 2000 additional single amino acid variants. This data set is available at the ProteomeXchange consortium via PRIDE repository (PXD010025).</P> [FIG OMISSION]</BR>

Development of a FFQ for breast cancer survivors in Korea

Shin, Woo-kyoung,Song, Sihan,Hwang, Eunkyung,Moon, Hyeong-Gon,Noh, Dong-Young,Lee, Jung Eun Cambridge University Press 2016 The British journal of nutrition Vol.116 No.10

<B>Abstract</B><P>Diet may play an important role in breast cancer recurrence or survival, and therefore assessment of long-term diet among breast cancer survivors is important in breast cancer survivorship research. Given that the diet of breast cancer survivors may differ from that of the general population, the use of a FFQ specific to this group may be needed. The objective of this study was to develop a FFQ for breast cancer survivors, the most commonly used tool to measure long-term dietary patterns in nutritional epidemiological studies. We collected information on the foods and amounts of foods consumed using 3-d dietary records from a total of 192 women who had been diagnosed with stage I-III breast cancers and had undergone breast cancer surgery at least 6 months before the baseline study. A total of 1254 foods and dishes consumed were re-grouped by the similarity of the main ingredients and/or serving units, and several dishes commonly consumed among the Korean population were added. After we performed contribution analyses and variability analyses to detect between-person variation for selected nutrients, we listed a total of 123 foods and dishes for the FFQ specific to breast cancer survivors. Our breast cancer survivor-specific FFQ can be used to estimate long-term dietary intake and to examine its association with breast cancer prognosis in epidemiological studies of breast cancer in Korea.</P>

Effect of a Dose-Escalation Regimen for Improving Adherence to Roflumilast in Patients with Chronic Obstructive Pulmonary Disease

Hwang, Hyunjung,Shin, Ji Young,Park, Kyu Ree,Shin, Jae Ouk,Song, Kyoung-hwan,Park, Joonhyung,Park, Jeong Woong The Korean Academy of Tuberculosis and Respiratory 2015 Tuberculosis and Respiratory Diseases Vol.78 No.4

Background: The adverse effects of the phosphodiesterase-4 inhibitor roflumilast, appear to be more frequent in clinical practice than what was observed in chronic obstructive pulmonary disease (COPD) clinical trials. Thus, we designed this study to determine whether adverse effects could be reduced by starting roflumilast at half the dose, and then increasing a few weeks later to $500{\mu}g$ daily. Methods: We retrospectively investigated 85 patients with COPD who had taken either $500{\mu}g$ roflumilast, or a starting dose of $250{\mu}g$ and then increased to $500{\mu}g$. We analyzed all adverse events and assessed differences between patients who continued taking the drug after dose escalation and those who had stopped. Results: Adverse events were reported by 22 of the 85 patients (25.9%). The most common adverse event was diarrhea (10.6%). Of the 52 patients who had increased from a starting dose of $250{\mu}g$ roflumilast to $500{\mu}g$, 43 (82.7%) successfully maintained the $500{\mu}g$ roflumilast dose. No difference in factors likely to affect the risk of adverse effects, was detected between the dose-escalated and the discontinued groups. Of the 26 patients who started with the $500{\mu}g$ roflumilast regimen, seven (26.9%) discontinued because of adverse effects. There was no statistically significant difference in discontinuation rate between the dose-escalated and the control groups (p=0.22). Conclusion: Escalating the roflumilast dose may reduce treatment-related adverse effects and improve tolerance to the full dose. This study suggests that the dose-escalated regimen reduced the rate of discontinuation. However, longer-term and larger-scale studies are needed to support the full benefit of a dose escalation strategy.