Ultra-energy-efficient analog-to-digital converters based on single-electron transistor/CMOS hybrid technology for biomedical applications

Lee, Jieun,Choi, Changmin,Park, Sungwook,Chung, In-Young,Kim, Chang-Joon,Park, Byung-Gook,Kim, Dong Myong,Kim, Dae Hwan Institute of Physics 2009 Semiconductor science and technology Vol.24 No.11

<P>Ultra-energy-efficient analog-to-digital converters (ADCs) based on single-electron transistor (SET)/complementary metal-oxide-semiconductor (CMOS) hybrid technology are proposed as a solution to sense and process biomedical signals. Our results show the energy efficiency of 0.82 pJ/state, which is lower than that in previously reported energy-efficient ADCs. The performance and dissipated power of proposed ADCs are estimated and compared with those of CMOS ADCs by using Lee's SPICE model including non-ideal effects of the experimental data. While the proposed ADC shows an operating power lower by two orders of magnitude than that of the CMOS flash-type ADC, the number of required transistors is about 10% of that in the CMOS flash-type ADC. The peak-to-valley current ratio in Coulomb oscillation of SETs used in the circuit implementation has the range of 1.15–1.5, which is consistent with the experimental result of top-down approached Si-based SETs at <I>T</I> = 77–100 K. From the perspective of the immunity to the gate capacitance <I>C<SUB>cg</SUB></I> mismatch and the background charge <I>Q</I><SUB>0</SUB> noise, it is shown that the criteria of SET/CMOS hybrid ADCs are Δ<I>C<SUB>cg</SUB></I> ⩽ 0.02 × <I>C<SUB>cg</SUB></I> (with <I>C<SUB>cg</SUB></I> = 0.24 aF) and Δ<I>Q</I><SUB>0</SUB> ⩽ 0.23<I>q</I>, respectively.</P>

발달장애학생의 성인기 전환교육에 대한 메타적 중요도-실행도(IPA) 분석 : 2000년 이후 국내 논문을 중심으로

황지은 ( Hwang¸ Jieun ),이미지 ( Lee¸ Miji ),박지현 ( Park¸ Jihyun ) 한국지적장애교육학회 2021 지적장애연구 Vol.23 No.3

본 연구는 교사인식에 따른 국내 발달장애 대상 성인기 전환교육에 대한 중요도-실행도(IPA) 연구를 메타적으로 분석함으로써 지금까지 이루어진 전환교육의 하위영역별 중요성과 실행도를 종합적인 관점에서 검토하고 앞으로의 접근 방향성을 제시하는 데 목적을 두고 있다. 이를 위해 2000년대 이후 출판된 발달장애학생들의 성인기 전환교육에 관한 교사인식을 다룬 연구 중에서 중요도와 실행도를 모두 포함하는 총 14편의 연구를 대상으로 메타적인 분석을 실행하였다. 연구의 결과는 다음과 같다. 첫째, 각 연구에 대한 개별 매트릭스를 도출한 뒤 하나의 전체 매트릭스로 통합하고 사분면에 제시된 중영역의 특성을 바탕으로 분석한 결과, ‘전환교육 계획 및 실행, 진로/직업, 전환 협력, 교사 역량, 학생 역량’이라는 5개의 주제를 도출하였으며, 이를 다시 사분면에 따른 주제별 비율로 제시하였다. 둘째, 전환주제별 세부항목이 사분면에 위치하는 양상을 중복성과 단일성 여부로 나누어 분석한 결과, 2개 이상의 사분면에 중복 위치한 항목이 다수 나타났고 단일 사분면에 위치한 항목들도 주제별로 확인할 수 있었다. 이러한 IPA 매트릭스에 대한 메타적 의미 분석에 따라 발달장애 대상 전환교육의 현 실정을 점검하고 앞으로의 지원 방향성 및 후속 연구에 시사하는 바를 논의하였다. The purpose of this study is to review the degrees of importance and performance of subcategories of transition education from a holistic perspective and to present the direction of future approach by meta-importance-performance analysis (IPA) studies of transition education to adulthood for students with developmental disabilities in Korea regarding teachers’ perceptions. A meta-analyzing method was conducted on the 14 studies published since 2000s, including both importance and performance. The analysis areas are as follows: the entire analysis of the key information presented in the 14 studies, a meta-analysis with the entire IPA matrix applied, and subjects derivation based on subcategories of transition education and its’ quadrant layout aspect analysis. As a result of the study, first, five themes, 'transition education planning and implementation, career/job, transition cooperation, teacher competency, and student competency', were derived from the characteristics of the subcategories presented in the quadrant and then they were presented again as a topic-specific ratio according to the quadrant. Second, the detailed items of each transition topic were analyzed by dividing them into redundancy and unity, and many items were found to be overlapped in two or more quadrants, and items located in a single quadrant could be checked by subjects. Following the meta-meaning analysis of these IPA matrices, the current state of transition education for students with developmental disabilities was examined and implications for future support directions and subsequent studies were discussed.

Plasmonic nano-necklace arrays <i>via</i> reconstruction of diblock copolymer inverse micelle nanotemplates

Lee, Ji Yong,Lee, Jieun,Jang, Yu Jin,Lee, Juyon,Jang, Yoon Hee,Kochuveedu, Saji Thomas,Lee, Sang Soo,Kim, Dong Ha Royal Society of Chemistry 2011 SOFT MATTER Vol.7 No.1

<P>We present a facile strategy for the generation of plasmonic nano-necklace arrays by introducing metallic precursors into strings of reconstructed inverse micelle nanotemplates which are induced by applying sequential selective solvent treatment and solvent vapour annealing for quasi-hexagonal arrays of poly(styrene-<I>block</I>-2-vinyl pyridine) inverse micelles.</P> <P>Graphic Abstract</P><P>A generalized protocol to fabricate plasmonic nano-necklace arrays with controlled composition was suggested <I>via</I> reconstruction of inverse micelle nanotemplates. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0sm00972e'> </P>

Clinical characteristics of young age onset gastric cancer in Korea

( Jieun Lee ),( Myung-ah Lee ),( In-ho Kim ),( In Hee Lee ),( Sang Yooung Roh ) 대한내과학회 2015 대한내과학회 추계학술대회 Vol.2015 No.1

Purpose: Gastric cancer is the fourth most common cancer worldwide and more frequently detected in Asian countries including Korea and Japan. The incidence of young-age gastric cancer (GC) is increasing worldwide, but clinical behavior of young-age GC patients is not well established. We retrospectively analyzed the clinical features and outcomes of GC diagnosed at young-age population. Methods: Between Jan. 2009 to Jan. 2015, 163 patients diagnosed as early, advanced, recurrent, or metastatic GC were analyzed. Based on medical records, authors analyzed the clinicopathologic characteristics and survival outcomes including overall survival (OS), disease free survival (DFS), and progression free survival (PFS). Results: One-hundred and four patients (82.8%) patients were diagnosed as GC at their thirties; especially 81 patients (31.2%) patients were diagnosed over 35 years of age. Forty-one (25.6%) patients had familial history of cancer at first or second-degree relatives. Among 41 patients, 19 (46.3%) patients had familial history of GC. The ratio of early GC and advanced GC were relatively similar (47.2% vs. 52.8%, respectively). Among stage II and III patients, 45 patients received 5-FU based adjuvant chemotherapy and recurrence rate was 48.9%. Among patients diagnosed as recurrent or metastatic GC, recurrent GC patients showed relatively superior PFS and OS after cancer recurrence, compared to metastatic GC patients, but without statistical significance. Among metastatic GC patients, patients receiving palliative debulking surgery for ovary metastases showed superior PFS compared to patients who only received palliative systemic chemotherapy (p=0.021, PFS 7.7 vs. 3.37 months, respectively). Conclusions: Young age GC were commonly diagnosed attheir thirties, with preference of familial history for GC. The incidence of advanced GC in young age patients were higher compared to general patient population. Among recurrent GC patients, palliative debulking surgery might have role for superior survival outcomes. Considering relatively higher incidence for advanced GC, active surveillance among young age patients with familial history for gastric cancer is warranted.

Complementary Silicon Nanowire Hydrogen Ion Sensor With High Sensitivity and Voltage Output

Jieun Lee,Jin-Moo Lee,Jung Han Lee,Won Hee Lee,Mihee Uhm,Byung-Gook Park,Dong Myong Kim,Yong-Joo Jeong,Dae Hwan Kim IEEE 2012 IEEE electron device letters Vol.33 No.12

<P>Complementary Si nanowire (SiNW) hydrogen ion sensors with high sensitivity and robust voltage output are demonstrated on a 6-in silicon-on-insulator wafer using a conventional wafer-level top-down process. The proposed SiNW sensors exhibit a logic threshold voltage shift of 88.9 mV/pH and an output voltage swing of 162 mV/pH. Furthermore, a simplified analytical model confirms that the proposed sensors have an output voltage swing that is 1.6 times larger than single SiNW sensor counterparts with a resistive load. Therefore, the proposed fabrication approach is expected to be a good solution for a very sensitive voltage readout scheme for the mass production of top-down processed biosensors.</P>

Reporting nationwide monitoring results about high risk pests in 2018

Jieun Lee,Seunghwan Lee,Jong-Seok Park,Hyojoong Kim,Ki-jeong Hong,Chuleui Jung,Dong-soon Kim,Wonhoon Lee 한국응용곤충학회 2019 한국응용곤충학회 학술대회논문집 Vol.2019 No.04

고위험해충에 대한 국내 유입/발생 여부를 상시 조사하고, 조기 대응하는 전국 민·관·학 예찰협력 네트워크 구성을 위하여, 고위험해충 11종(Bactrocera dorsalis, Solenopsis invicta, Cydia pomonella, Drosophila suzukii, Bactrocera depressa, Lobesia botrana, Proeulia sp., Aceria diospyri, Stephaitis takeyai, Bactrocera minax, Bactrocera tsuneonis)에 대하여 7개 대학(경상대학교, 군산대학교, 서울대학교, 순천대학교, 안동대학교, 제주대학교, 충북대학교)이 참여한 전국 권역별 예찰조사를 2018년 6월부터 10월까지 실시하였다. 조사결과, B. dorsalis, S. invicta, C. pomonella은 발견되지 않았으며, D. suzukii (3,584개체), B. depressa (21개체) 채집되었다. 포도, 단감, 감귤의 유입우려해충(L. botrana, P. sp., A. diospyri, S. takeyai, B. minax, B. tsuneonis)은 발견되지 않았다. 본 조사연구를 통하여, 고위험해충을 조기 탐색할 수 있는 7개 대학을 통한 전국단위의 감시체계를 구축하였고, 수출단지 상대국우려병해충 및 수출품목에 대한 정밀 예찰과 관리를 통한 수출지원, 국경 이후 병해충 예찰․관리를 위한 거점 확보의 성과를 이루었다.

The Tolerability of Mirtazapine Augmentation in Schizophrenic Patients Treated with Risperidone: A Preliminary Randomized Placebo-controlled Trial

Jieun Lee,Sung Joon Cho,Kang Soo Lee,Keunyoung Yook,최아영,Sungjae Lee,김보라,Keung-Hyang Kim,Tae Kyou Choi,이상혁 대한정신약물학회 2011 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.9 No.2

Objective: Some patients with schizophrenia may need mirtazapine augmentation to improve negative and cognitive symptoms. However there have been a few studies about the tolerability of mirtazapine augmentation to antipsychotics such as akathisia,extrapyramydal symptoms, weight gain, and body mass index (BMI). Methods: This study was an eight-week double-blind, randomized controlled trial (RCT) of mirtazapine augmentation to risperidone. Twenty-one stabilized participants diagnosed with schizophrenia and undergoing treatment with risperidone were randomized to adjunctive treatment with mirtazapine (15 mg/day for the first two weeks, 30 mg/day for the next six weeks) or placebo. Eleven patients were assigned to the mirtazapine group, and nine patients were given placebo. Results: There was no significant difference between the mirtazapine and placebo groups with respect to Barnes Akathisia rating Scale (BAS) and Sympsom-Angus Scale (SAS). However, the mirtazapine group exhibited a statistically significant increase in weight and BMI (p<0.05). Conclusion: These results suggest that mirtazapine augmentation can be tolerable in schizophrenic patients treated with risperidone;however, we should pay attention to the weight gain with mirtazapine. Our results should be replicated in a large-scale lengthy trial.

Effects of Hahella chejuensis-Derived Prodigiosin on UV-Induced ROS Production, Inflammation and Cytotoxicity in HaCaT Human Skin Keratinocytes

( Jieun Lee ),( Hyun Ju Kim ),( Sang Jun Lee ),( Moo-seung Lee ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.3

Prodigiosins, which are natural tripyrrole red pigments and synthetic derivatives, reportedly have multiple biological effects mainly on various types of cancer cells. However, the effects of bacterial prodigiosin on non-cancerous HaCaT human skin keratinocytes have not been reported. Therefore, the present study aimed to investigate the functional activities of prodigiosin derived from cultures of the bacterium Hahella chejuensis in HaCaT cells. Cell viability, the cell proliferation rate, and reactive oxygen species (ROS) production in vitro were assayed following treatment of HaCaT cells with prodigiosin. Prodigiosin did not cause cytotoxicity and notably increased proliferation of HaCaT cells. Furthermore, prodigiosin reduced ultraviolet (UV) irradiation-induced ROS production and the inflammatory response in HaCaT cells. More importantly, prodigiosin reduced matrix metalloproteinase-9 expression and increased collagen synthesis in UV-irradiated HaCaT cells, demonstrating that it elicits anti-aging effects. In conclusion, our results reveal that H. chejuensis-derived prodigiosin is a potential natural product to develop functional cosmetic ingredients.

The Caenorhabditis elegans AMP-activated protein kinase AAK-2 is phosphorylated by LKB1 and is required for resistance to oxidative stress and for normal motility and foraging behavior.

Lee, Hyojin,Cho, Jeong Soo,Lambacher, Nils,Lee, Jieun,Lee, Se-Jin,Lee, Tae Hoon,Gartner, Anton,Koo, Hyeon-Sook American Society for Biochemistry and Molecular Bi 2008 The Journal of biological chemistry Vol.283 No.22

<P>AAK-2 is one of two alpha isoforms of the AMP-activated protein kinase in Caenorhabditis elegans and is involved in life span maintenance, stress responses, and germ cell cycle arrest upon dauer entry. We found that AAK-2 was phosphorylated at threonine 243 in response to paraquat treatment and that this phosphorylation depends on PAR-4, the C. elegans LKB1 homologue. Both aak-2 mutation and par-4 knockdown increased the sensitivity of C. elegans worms to paraquat, and the double deficiency did not further increase sensitivity, indicating that aak-2 and par-4 act in a linear pathway. Both mutations also slowed body bending during locomotion and failed to reduce head oscillation in response to anterior touch. Consistent with this abnormal motility and behavioral response, expression of the AAK-2::green fluorescent protein fusion protein was observed in the ventral cord, some neurons, body wall muscle, pharynx, vulva, somatic gonad, and excretory cell. Our study suggests that AMPK can influence the behavior of C. elegans worms in addition to its well known function in metabolic control.</P>

High expression level of SOX2 is significantly associated with shorter survival in patients with thymic epithelial tumors

Lee, Guk Jin,Lee, Heejung,Woo, In Sook,Kim, Taejung,An, Ho Jung,Choi, Hyun Joo,Lee, Youn Soo,Lee, Kyo Young,Lee, Jieun,Kang, Jin-Hyoung Elsevier 2019 Lung cancer Vol.132 No.-

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>Thymic epithelial tumors (TET) are heterogenous tumors which are composed of thymoma (TM) and thymic carcinoma (TC). We attempted to determine differences in gene expression between TM and TC, and to determine the effect of such genes on the prognosis of patients with TET.</P> <P><B>Materials and methods</B></P> <P>Gene expression profiles of SOX2, OCT-4, IGF-1, IGF-1R and IR mRNA transcripts in tumor tissues of TM and TC were determined using real-time PCR (RT-PCR). We constructed tissue microarray with 140 paraffin-embedded tumor tissues and performed immunohistochemistry (IHC) for IGF-1R-related signaling molecules, including SOX2, IGF-1, IGF-1R and pAKT.</P> <P><B>Results</B></P> <P>SOX2 mRNA expression was notably higher (216-fold) in TCs than in TMs. However, there was no significant difference in expression of IGF-1, IGF-1R, OCT-4 or IR between the two tumor types. In IHC results, SOX2 (HR: 7.57, P = 0.001) and IGF-1 (HR: 9.43, P = 0.001) expression levels in TC were significantly higher than those in TM. There was a significant correlation in expression of SOX2 with IGF-1 (P = 0.021) and pAKT (P = 0.026). In univariate analysis, clinical TNM stage, WHO classification, serum LDH, expression of SOX2, IGF-1R, IGF-1 and pAKT, were significantly correlated with overall survival (OS). Multivariate analysis using a forward-selection procedure revealed that clinical N stage (HR: 4.08, P < 0.001), M stage (HR: 3.37, P = 0.001) and SOX2 expression (HR: 4.53, P = 0.010) were significantly associated with OS.</P> <P><B>Conclusions</B></P> <P>SOX2 is expressed significantly higher in TC than in TM. SOX2 expression is also closely related to IGF-1 and pAKT expression. The higher expression of SOX2 is significantly associated with shorter survival in patients with TET.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Thymic epithelial tumors (TET) are divided into two broad categories, thymoma (TM) and thymic carcinoma (TC). </LI> <LI> Molecular biology of TETs are poorly understood. </LI> <LI> We suggest that SOX2 might be potential biomarker to predict biologic aggressiveness and poor prognosis in TETs. </LI> </UL> </P>