대장암의 시대적 변화

이정호,나양원,서병조,장석효,백인욱,이혁상 대한소화기학회 1999 대한소화기학회지 Vol.33 No.1

Background/Aims: This study was conducted to evaluate the chronological changes of colorectal cancer in Korea. Methods: A retrospective analysis of 352 cases with colorectal cancer treated in the period from 1988 to 1996 (recent period) was performed and the results were compared with the previously reported study involving 221 cases with colorectal cancer treated in the period from 1975 to 1987 (past period). Results: The proportion of patients over 60 years in the recent period was 46%, which was significantly higher than that in the past period (30%). Dukes' C patients were 40.6% in the recent period. Although Dukes' D patients were lowered by 6.8%, their proportion wa still 21%. The resection rate was raised by 9.6% to reach 87.8% in the recent period and postoperative morbidity and mortality were decreased. Five-year survival rate was 56.0% in the recen period, it is higher than that of the past period (52%). Five-year survival rate was 100% in Dukes A patients, 83.9% in Dukes' B patients, 53.3% in Dukes' C patients and 8.7% in Dukes' D patient (p=0.000). Conclusions: The incidence of colorectal cancer in the aged group has been increasing. The proportion of Dukes' D patients is decreased. Five-year survival rate of the recent period is higher than that of the past period by 4%. (Kor J Gastroenterol 1999;33:51 - 57)

대장암의 시대적 변화

이정호,나양원,서병조,장석효,백인욱,이혁상 大韓消化器病學會 1999 大韓消化器病學會誌 Vol.33 No.1

Anti-biofouling 광생물반응기를 이용한 미세조류 배양 연구

나인욱(In Wook Nah),서민호(Min-ho Suh),안수한(Soohan Ahn),황경엽(Kyung-Yub Hwang) 한국생물공학회 2011 KSBB Journal Vol.26 No.6

In this study, we carried out the development of high performance photobioreactor, which can be used to develop the biological CO₂ fixation technology as well as the renewable biofuels, the microalgae Botryococcus braunii. When B. Braunii was cultured in Anti-biofouling photobioreator, growth rate of it showed about 3 times higher than that of bubble column photobioreactor at the same conditions. In case of photobioreactor without bead, after 3 days culture time, biofouling occur rapidly in wall of the photobioreactor. However, with bead 5% (V/V), biofouling do not occur all experimental days.

A bibliometric evaluation of research performance in different subject categories

Nah, In Wook,Kang, Dai-Shin,Lee, Dae-Hee,Chung, Yun-Chul Wiley Subscription Services, Inc., A Wiley Company 2009 JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SC Vol.60 No.6

<P>In this article, bibliometric indicators with publications and citations are used for a direct research-performance comparison among different or interdisciplinary categories, the work of individual scientists, and their research teams and institutions. For example, basic research performances of some projects at the Korea Institute of Science and Technology (KIST) were assessed using bibliographic factors with IPQ-Normalized impact factor to compare with an international level and other research groups in different or interdisciplinary fields. Some research teams at KIST showed higher quality publications in terms of the international measures.</P>

In situ coating of Poly(3,4-ethylenedioxythiophene) on sulfur cathode for high performance lithium–sulfur batteries

Song, Jongchan,Noh, Hyungjun,Lee, Jinhong,Nah, In-Wook,Cho, Won-Il,Kim, Hee-Tak Elsevier 2016 Journal of Power Sources Vol.332 No.-

<P><B>Abstract</B></P> <P>Polysulfide (PS) shuttle, which is one of the critical problems that need to be addressed for realizing lithium sulfur batteries, can be suppressed by confining PSs within microporous or mesoporous templates. However, PS dissolution through the external opening of the templates has to be further prevented. In this work, a poly (3,4-ethylenedioxythiophene) (PEDOT) layer is formed in situ on the CMK-3/S cathode by inducing the electro-oxidative polymerization of the EDOT monomer included in electrolytes during pre-charging. The PEDOT layer covering the external cathode surface functions as a PS blocking layer, which suppresses the PS shuttle and, thus, improves the cycling stability. The spectroscopic analysis indicates that the PEDOT layer reduces the decomposition of the electrolyte by preventing any reaction between the active PS species and electrolytes. Therefore, the in situ formation of the PS blocking layer from the electrolyte additive provides a simple and effective method to improve the cycling stability of lithium sulfur batteries.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A Poly (3,4-ethylenedioxythiophene) (PEDOT) was formed in situ on sulfur electrode. </LI> <LI> A pre-charging step induced the electro-oxidative polymerization of EDOT. </LI> <LI> The PEDOT layer suppressed polysulfide shuttle and electrolyte decomposition. </LI> <LI> The cyclability of Li-S battery was improved by the in situ formed PEDOT layer. </LI> </UL> </P>

췌두부암의 임상적 고찰

나양원,장석효,박영래,백인욱,이혁상 대한소화기학회 1999 대한소화기학회지 Vol.33 No.5

Background/Aims: Pancreatic head cancer has been characterized by a low resectability and poor survival rate. This study was conducted to examine the resectability and postoperative results of pancreatic head cancer. Methods: A retrospective study was performed for 45 patients with pancreatic head cancer treated at our department from 1988 through 1997. Results: The cancer was prevalent in the 6th and 7th decades (71.1%) of life. The male-to-female ratio was 1.7:1. Ninety-five percent of the patients was in either TNM stage III or IV. Pancreatoduodenectomy was executed in 8 patients (17.8%) without operative mortality or anastomotic leakage. Out of 26 patients who underwent biliary bypass surgery, 24 were subjected to concomitant gastrojejunostomy. Eleven patients (24.4%) received non-operative management. Actuarial survival rates of 1 and 4 years after pan creatoduodenectomy were 75.0% and 45.0%, respectively. The median survival after pancreatoduo denectomy was 27 months, which was significantly longer than those after bypass surgery (8 months or after non-operative treatment (4 months)(p$lt;0.0005). Conclusions: Pancreatoduodenectomy can be safely performed for pancreatic head cancer without operative mortality or major complication. Early detection and the development of more promising adjuvant therapies are required to improve resectability and to prolong survival after resection of pancreatic head cancer.

Cyanoguanidine - formaldehyde Resin에 의한 반응성 염료 응집 특성

나인욱(In Wook Nah),진양오(Yang Oh Jin),황경엽(Kyung Yub Hwang) 大韓環境工學會 2000 대한환경공학회지 Vol.22 No.12

Crumpled rGO-supported Pt-Ir bifunctional catalyst prepared by spray pyrolysis for unitized regenerative fuel cells

Kim, In Gyeom,Nah, In Wook,Oh, In-Hwan,Park, Sehkyu Elsevier Sequoia 2017 Journal of Power Sources Vol. No.

<P><B>Abstract</B></P> <P>Three-dimensional (3D) crumpled reduced graphene oxide supported Pt-Ir alloys that served as bifunctional oxygen catalysts for use in untized regenerative fuel cells were synthesized by a facile spray pyrolysis method. Pt-Ir catalysts supported on rGO (Pt-Ir/rGOs) were physically characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) to observe change in composition by heat treatment, alloying, and morphological transition of the catalysts. Their catalytic activities and stabilities for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) conditions were electrochemically investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV), potential cycling and hold tests on the rotating disk electrode (RDE). Pt-Ir/rGO with no post heat-treatment (Pt-Ir/rGO_NP) showed a lower activity for ORR and OER although metal nanoparticles decorated on the support are relatively small. However, Pt-Ir/rGO showed remarkably enhanced activity following heat treatment, depending on temperature. Pt-Ir/rGO heat-treated at 600 °C after spray pyrolysis (Pt-Ir/rGO_P600) exhibited a higher activity and stability than a commercially available Pt/C catalyst kept under the ORR condition, and it also revealed a comparable OER activity and durability versus the commercial unsupported Ir catalyst.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Pt-Ir/rGO was synthesized by a facile spray pyrolysis and following heat-treatment. </LI> <LI> ORR and OER catalytic activities of Pt-Ir/rGO were enhanced by post heat treatment. </LI> <LI> Pt-Ir/rGO_P600 exhibited higher catalytic activities than commercial catalysts. </LI> <LI> Pt-Ir/rGO_P600 showed superior stabilities under reducing and oxidizing conditions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Sonocatalytic reduction of nitrate using magnetic layered double hydroxide: Implications for removal mechanism

Wong, Kien Tiek,Saravanan, Pichiah,Nah, In Wook,Choi, Jaeyoung,Park, Chulhwan,Kim, Namchan,Yoon, Yeomin,Jang, Min Elsevier 2019 CHEMOSPHERE - Vol.218 No.-

<P><B>Abstract</B></P> <P>In this study, magnetic layered double hydroxides (mag-LDHs) were synthesized through compositing magnetite with three different metals (Mg, Cu and Al) under ultrasound (US, 100 kHz frequency and 50 W power). For the first time, mag-LDHs were applied to sonocatalytic reduction of nitrate (NO<SUB>3</SUB> <SUP>−</SUP>) and the reduction mechanism were determined by conducting kinetic tests and various spectroscopic analyses. Based on the kinetic data, NO<SUB>3</SUB> <SUP>−</SUP> reduction and the selectivity for N<SUB>2</SUB> highly depends on the ratio between Mg/Al, solution pH and sonication frequency. The best condition for sonocatalytic denitrification was found to be pH 7 operated under 100 kHz (50% power) using the catalyst with lowest amount of Al (mag-LDH-Al<SUB>0.3</SUB>Mg<SUB>1.5</SUB>). As a proposed mechanism, NO<SUB>3</SUB> <SUP>−</SUP> is initially reduced to NO<SUB>2</SUB> <SUP>−</SUP> by Cu<SUP>0</SUP>, and then further reduced to N<SUB>2</SUB>/NH<SUB>4</SUB> <SUP>+</SUP> by Mg<SUP>0</SUP>. Hypothetically Al<SUP>0</SUP> could provide sorption sites for hydrogen radicals (·H) dissociated from ultrasound, hence served as reducing sites in denitrification process. The XPS analysis showed an increased peak of Cu<SUP>0</SUP> after the sonocatalytic reduction when catalyst has lower amount of Al. The excessive hydrogen adsorbed on Al<SUP>0</SUP> might spill-over to the adjacent Cu, thus reducing the CuO into Cu<SUP>0</SUP> at high temperature created by the implosion of the microbubbles. Without the use of consumable reducing agents (i.e. H<SUB>2</SUB> gas), sonocatalytic reduction could be a potential candidate of remediation method to treat NO<SUB>3</SUB> <SUP>−</SUP> polluted water with high N<SUB>2</SUB> selectivity and easy magnetic recovery.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sonocatalytic reduction of NO<SUB>3</SUB> <SUP>−</SUP> was studied for the first time. </LI> <LI> Magnetically separable Mag-LDH was synthesized via ultrasound irradiation. </LI> <LI> Denitrification occurs without reducing chemicals. </LI> <LI> High selectivity for N<SUB>2</SUB> was achieved by mag-LDH under sonication. </LI> <LI> Solution pH and percentage of Mg play an important role in denitrification. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Preparation of Porous Nanostructures Controlled by Electrospray

( Dung The Nguyen ),( In Wook Nah ),( Kyo-seon Kim ) 한국화학공학회 2015 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.53 No.5

Various solid structures were prepared by electrospray technique. In this process, liquid flows out from a capillary nozzle under a high electrical potential and is subjected to an electric field, which causes elongation of the meniscus to form a jet. In our study, by controlling the amount of polyvinyl pyrrolydone in precursor solution, the jet either disrupted into droplets for the formation of spherical particles or was stretched in the electric field for the formation of fibers. During the electrospray process, the ethanol solvent was evaporated and induced the solidification of precursors, forming solid particles. The evaporation of ethanol solvent also enhanced the mass transport of solutes from the inner core to the solid shell, which facilitated fabrication of porous and hollow structure. The network structures were also prepared by heating the collector.