Cure Behavior of Epoxy Binder for Anisotropic Conductive Film with Low Melting Point Filler

Ji-Won Baek,Yong-Sung Eom,Jong-Tae Moon,Jong-Min Kim,Jae-Do Nam 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.10

Synthesis of SnS Thin Films by Atomic Layer Deposition at Low Temperatures

Baek, In-Hwan,Pyeon, Jung Joon,Song, Young Geun,Chung, Taek-Mo,Kim, Hae-Ryoung,Baek, Seung-Hyub,Kim, Jin-Sang,Kang, Chong-Yun,Choi, Ji-Won,Hwang, Cheol Seong,Han, Jeong Hwan,Kim, Seong Keun American Chemical Society 2017 Chemistry of materials Vol.29 No.19

<P>Two-dimensional (2-D) metal chalcogenides have received great attention because of their unique properties, which are different from bulk materials. A challenge in implementing 2-D metal chalcogenides in emerging devices is to prepare a well-crystallized layer over large areas at temperatures compatible with current fabrication processes. Tin monosulfide, a <I>p</I>-type layered semiconductor with a high hole mobility, is a promising candidate for realizing large-area growth at low temperatures because of its low melting point. However, tin sulfides exist in two notable crystalline phases, SnS and SnS<SUB>2</SUB>. Therefore, it is imperative to control the oxidation state of Sn to achieve a pure SnS film. Here, the synthesis of SnS thin films by atomic-layer-deposition (ALD) is demonstrated using bis(1-dimethylamino-2-methyl-2-propoxy)tin(II) and H<SUB>2</SUB>S as Sn and S sources, respectively, over a wide temperature window (90–240 °C). Impurities such as carbon, oxygen, and nitrogen were negligibly detected. The morphological evolution of plate-like orthorhombic SnS grains was observed above 210 °C. Moreover, properties of thin film transistors and gas sensors using SnS films as the active layers were investigated. The SnS ALD process would provide promising opportunities to exploit the intriguing properties of the 2-D metal chalcogenides for realizing emerging electronic devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cmatex/2017/cmatex.2017.29.issue-19/acs.chemmater.7b01856/production/images/medium/cm-2017-018563_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cm7b01856'>ACS Electronic Supporting Info</A></P>

Bax-induced cell death of Arabidopsis is meditated through reactive oxygen-dependent and -independent processes

Baek, Dong-won,Nam, Jae-sung,Koo, Yoon-Duck,Kim, Doh-Hoon,Lee, Ji-young,Jeong, Jae-Cheol,Kwak, Sang-Soo,Chung, Woo-Sik,Lim, Chae-Oh,Bahk, Jeong-Dong,Hong, Jong-Chan,Lee, Sang-Yeol,Maki Kawai-Yamada,Hi Plant molecular biology and biotechnology research 2004 Plant molecular biology and biotechnology research Vol.2004 No.-

An Arabidopsis protoplast system was developed for dissecting plant cell death in individual cells. Bax, a mammalian pro-apoptotic member of the Bcl-2 family, induces apoptotic-like cell death in Arabidopsis. Bax accumulation in Arabidopsis mesophyll protoplasts expressing murine Bax cDNA from a glucocorticoid-inducible promoter results in cytological characteristics of apoptosis, namely DNA fragmentation, increased vacuolation, and loss of plasma membrane integrity. In vivo targeting analysis monitored using jellyfish green fluorescent protein (GFP) reporter indicated full-length Bax was localized to the mitochondria, as it does in animal cells. Deletion of the carboxyl-terminal transmembrane domain of Bax completely abolished targeting to mitochondria. Bax expression was followed by reactive oxygen species (ROS) accumulation. Treatment of protoplasts with the antioxidant N-acetyl-L-cysteine (NAC) during induction of Bax expression strongly suppressed Bax-mediated ROS production and the cell death phenotype. However, some population of the ROS depleted cells still induced cell death, indicating that there is a process that Bax-mediated plant cell death is independent of ROS accumulation. Accordingly suppression of Bax-mediated plant cell death also takes place in two different processes. Over-expression of a key redox-regulator, Arabidopsis nucleoside diphosphate kinase 2 (AtNDPK2) down-regulated ROS accumulation and suppressed Bax-mediated cell death and transient expression of Arabidopsis Bax inhibitor-1 (AtBI-1) substantially suppressed Bax-induced cell death without altering cellular ROS level. Taken together. our results collectively suggest that the Bax-mediated cell death and its suppression in plants is mediated by ROS-dependent and -independent processes.

Analysis of increased nuchal translucency: Chorionic villi sampling and second-trimester level II sonography

Ji Eun Park,Ji Kwon Park,In Ae Cho,Jong Chul Baek,Min Young Kang,Jae Ik Lee,Jeong Kyu Shin,Won Jun Choi,Soon Ae Lee,Jong Hak Lee,Won Young Paik 대한의학유전학회 2014 대한의학유전학회지 Vol.11 No.2

Purpose: To assess the outcomes of increased fetal nuchal translucency (NT), to aid in prenatal counseling and management in our practice. Materials and Methods: We retrospectively reviewed the medical records of patients who underwent first trimester fetal karyotyping using chorionic villi sampling (CVS) and second trimester level II sonography for a fetal NT thickness ≥3.0 mm between 11 weeks and 13 weeks 6 days' gestation, at Gyeongsang National University Hospital. Pediatric medical records and a telephone interview were used to follow-up live-born children. Exclusion criteria included incomplete data and CVS for other indications. Results: Seventy cases met the inclusion criteria (median NT thickness, 4.7 mm; range, 3.0-16.1 mm). Twenty-nine cases (41.4%) were aneuploid. The prevalence of chromosomal defects increased with NT thickness: NT 3.0-3.4 mm, 16.7%; NT 3.5-4.4 mm, 27.3%; NT 4.5-5.4 mm, 66.7%; NT 5.5-6.4 mm, 37.5%; NT ≥6.5 mm, 62.5%. The most common karyotype abnormality was trisomy 18 (n=12), followed by trisomy 21 (n=9). In chromosomally normal fetuses (n=41), fetal death occurred in 2 cases (4.9%), and structural malformations were found in 11 cases (26.8%). In chromosomally and anatomically normal fetuses (n=28), one child had neurodevelopmental delay (3.6%). Twenty-eight infants who had a prenatal increased NT were alive and well at follow-up (40%). Conclusion: Outcomes of increased fetal NT might help inform prenatal counseling and management. The high prevalence of chromosomal defects associated with increased fetal NT implies that CVS should be performed in the first trimester, particularly considering the stress associated with an uncertain diagnosis.

Inhibition of Drp1 Ameliorates Synaptic Depression, Aβ Deposition, and Cognitive Impairment in an Alzheimer's Disease Model

Baek, Seung Hyun,Park, So Jung,Jeong, Jae In,Kim, Sung Hyun,Han, Jihoon,Kyung, Jae Won,Baik, Sang-Ha,Choi, Yuri,Choi, Bo Youn,Park, Jin Su,Bahn, Gahee,Shin, Ji Hyun,Jo, Doo Sin,Lee, Joo-Yong,Jang, Cho Society for Neuroscience 2017 The Journal of neuroscience Vol.37 No.20

<P>Excessive mitochondrial fission is a prominent early event and contributes to mitochondrial dysfunction, synaptic failure, and neuronal cell death in the progression of Alzheimer's disease (AD). However, it remains to be determined whether inhibition of excessive mitochondrial fission is beneficial in mammal models of AD. To determine whether dynamin-related protein 1 (Drp1), a key regulator of mitochondrial fragmentation, can be a disease-modifying therapeutic target for AD, we examined the effects of Drp1 inhibitor on mitochondrial and synaptic dysfunctions induced by oligomeric amyloid-beta(A beta) in neurons and neuropathology and cognitive functions in A beta precursor protein/presenilin 1 double-transgenic AD mice. Inhibition of Drp1 alleviates mitochondrial fragmentation, loss of mitochondrial membrane potential, reactive oxygen species production, ATP reduction, and synaptic depression in A beta-treated neurons. Furthermore, Drp1 inhibition significantly improves learning and memory and prevents mitochondrial fragmentation, lipid peroxidation, BACE1 expression, and A beta deposition in the brain in the AD model. These results provide evidence that Drp1 plays an important role in A beta-mediated and AD-related neuropathology and in cognitive decline in an AD animal model. Therefore, inhibiting excessive Drp1-mediated mitochondrial fission may be an efficient therapeutic avenue for AD.</P>

Characteristics and prognosis of patients with colorectal cancer-associated brain metastases in the era of modern systemic chemotherapy.

Baek, Ji Yeon,Kang, Myoung Hee,Hong, Yong Sang,Kim, Tae Won,Kim, Dae Yong,Oh, Jae Hwan,Lee, Seung Hoon,Park, Jin Hong,Kim, Jong Hoon,Kim, Sun Young M. Nijhoff ; Kluwer Academic Publishers 2011 Journal of neuro-oncology Vol.104 No.3

<P>Brain metastases (BM) occur in approximately 20-40% of cancer patients. The present study investigated the clinical outcomes of patients with BM from colorectal cancer (CRC) to assess the benefit of systemic chemotherapy (CT) administered after surgical or radiotherapeutic control of BM and to identify independent prognostic factors associated with survival after BM. Between August 2001 and July 2009, 118 patients with symptomatic BM from CRC received either cranial irradiation or craniotomy at two large cancer centers in South Korea. Retrospective review and statistical analysis of clinical characteristics and outcomes were performed for all patients. Median time from diagnosis of metastatic CRC to detection of BM was 12.2??months (range 0-76.2??months). Thirteen patients (11%) exhibited brain involvement at initial presentation. Median survival after BM development was 4.1??months [95% confidence interval (CI) 3.3-4.9??months]. Forty-six patients (40%) had been treated previously with the chemotherapeutic agents fluoropyrimidine, oxaliplatin, and irinotecan. Patients who received CT after BM exhibited significantly improved survival compared with those who did not (12.4 versus 3.1??months, respectively; P??<??0.001). Multivariate analysis revealed that CT intervention after presentation with BM was significantly associated with survival after BM, and the adjusted hazard ratio was 0.30 (95% CI 0.17-0.51, P??<??0.001). Although BM is a late-stage phenomenon in CRC, approximately two-thirds of patients were still unexposed to irinotecan or oxaliplatin at the development of BM in our study. Thus, additional chemotherapeutic intervention after BM associated with CRC may be beneficial for selected patients.</P>

The Determinants of Prices in Mobile Voice Market

Baek, Ji Won(백지원) 한국산업경제학회 2018 산업경제연구 Vol.31 No.5

본 연구에서는 이동전화서비스 시장에서의 요금 결정요인을 식별하고, 시장 구조 및 규제가 요금에 미치는 영향을 분석한다. 2002년부터 2014년까지 26개국에 대한 패널 데이터 자료를 이용하여 연립방정식 모형(simultaneous equations model)을 추정하였으며, 보완적으로 외생변수만을 고려한 축약형 모형(reduced form model)을 추정하여 구조 모형(structural form)과 결과가 일관되게 나옴을 확인하였다. 추정 결과, 모바일 네트워크 사업자(MNOs)의 시장 집중도는 요금에 유의한 영향을 준 반면, 가상이동통신사업자(MVNOs)의 도입이 요금 인하에 미친 영향은 유의하게 나타나지 않아, 성숙기에 접어든 모바일 서비스 시장에서의 사후규제(ex-post regulation)의 효과는 뚜렷하지 않는 것으로 추정되었다. 또한, 번호이동성(MNP )의 시행은 시장의 전환 비용이 낮은 경우에 한해 가격 인하에 통계적으로 유의한 영향을 주는 것으로 나타났다. 이는 약정기간 계약 등의 전환 비용을 낮추는 정책이 함께 수반될 때, 유효경쟁을 위한 규제의 실효성을 달성할 수 있음을 의미한다. 추가적으로, 본 연구는 모바일 음성서비스와 데이터서비스 사이의 일관된 대체관계를 확인하였다. This study examines the main determinants of mobile service prices and discusses the impact of market structure and regulations on retail prices in a mobile services market. A simultaneous equations model and a reduced form model are estimated using a panel dataset for 26 countries from 2002 to 2014. The estimation results suggest that the market concentration measured by the number of mobile network operators (MNOs) has a positive and statistically significant effect on prices, while the regulatory policy to facilitate new entrants (mobile virtual network operators, MVNOs) is not found to be significant, implying that ex-post regulation in a mature mobile market might not be as effective as expected in lowering prices. The implementation of mobile number portability (MNP ) has significant effects on price reduction only with low switching barriers. Additionally, we find the consistent evidence that there exists substitution relationship between mobile voice and mobile data services.

A Power-Efficient Voltage Up-Converting Circuit System

Won-Ji Lee,Kyoung-Su Lee,Jong-Min Baek,Jung-Hyun Song,Jae-Chul Park,Kee-Won Kwon 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7

We developed a low-power voltage upconverter system that is composed of charge pump, level detector, and level shifter, which generates 1.0uA-10V from 2.5V VDD using 0.18um CMOS technology. The efficiency of the Dickson’s charge pump was analysed with respect to the size of pumping capacitors and the number of pumping stages, and the optimum condition was chosen from the analysis results. The level detector senses VPP voltage in capacitive division way in order to eliminate the steady state VPP power dissipation through the resistive voltage divider. The power consumption in level shifters is reduced without sacrificing the switching speed by inserting a bootstrapped p-MOSFET between cross-coupled p-MOSFET and pull down n-MOSFET. Combing the three techniques the power consumption of voltage up-converting circuit system is saved by 28%.

Multi-omics Based Analysis for Investigation of Roseburia intestinalis as a Promising Butyrate-Producing Probiotic in Human Intestinal Epithelial Cells

Won-Suk SONG,Seo-Young KWON,Sung-Hyun JO,Ye-Rim KIM,Ji-Hyun BAEK,Min-Gyu KIM,Ju-Yeon HAN,Yun-Gon KIM 한국생물공학회 2023 한국생물공학회 학술대회 Vol.2023 No.4

High Throughput Receiver Structure for Underwater Communication

Baek, Chang-Uk,Jung, Ji-Won Taylor & Francis 2015 INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR NETWOR Vol.2015 No.-