Development of an improved method for determination of N-nitrosamines in drinking water using HPLC-FLD

Seonggyun Lee,Sungjin Jung,Sunyoung Park,Hekap Kim 한국분석과학회 2017 학술대회논문집 Vol.2017 No.11

Short Reads Phasing to Construct Haplotypes in Genomic Regions That Are Associated with Body Mass Index in Korean Individuals

Lee, Kichan,Han, Seonggyun,Tark, Yeonjeong,Kim, Sangsoo Korea Genome Organization 2014 Genomics & informatics Vol.12 No.4

Genome-wide association (GWA) studies have found many important genetic variants that affect various traits. Since these studies are useful to investigate untyped but causal variants using linkage disequilibrium (LD), it would be useful to explore the haplotypes of single-nucleotide polymorphisms (SNPs) within the same LD block of significant associations based on high-density variants from population references. Here, we tried to make a haplotype catalog affecting body mass index (BMI) through an integrative analysis of previously published whole-genome next-generation sequencing (NGS) data of 7 representative Korean individuals and previously known Korean GWA signals. We selected 435 SNPs that were significantly associated with BMI from the GWA analysis and searched 53 LD ranges nearby those SNPs. With the NGS data, the haplotypes were phased within the LDs. A total of 44 possible haplotype blocks for Korean BMI were cataloged. Although the current result constitutes little data, this study provides new insights that may help to identify important haplotypes for traits and low variants nearby significant SNPs. Furthermore, we can build a more comprehensive catalog as a larger dataset becomes available.

인공신경망을 이용한 공대지 유도폭탄의 투하가능영역 산출

김성균(Seonggyun Kim),박정호(Jeongho Park),박상혁(Sanghyuk Park),이승필(Seoungpil Lee),김길훈(Kilhun Kim) 한국항공우주학회 2018 韓國航空宇宙學會誌 Vol.46 No.4

투하 가능 영역(LAR)은 표적에 성공적으로 명중하기 위한 영역을 의미하여, 항공기에서 실시간으로 계산되어 조종사가 인지할 수 있도록 시현해 주어야한다. LAR는 폭탄의 투하조건, 표적의 탄착조건, 비행 시의 대기조건에 따라 변경된다. 본 논문에서는 인공신경망을 이용한 LAR 모델의 계산방법을 제시하였다. 기존의 LAR 모델에서 각 조건들을 변화하여 학습데이터를 생성하였으며, 인공신경망 학습을 통해 LAR 모델을 도출하였다. 기존 LAR 모델의 결과 데이터와 새로운 LAR 모델의 결과 데이터의 차이를 비교하여 모델의 정확도를 확인하였고, 계산시간을 비교하여 새로운 LAR 모델의 항공기에서 실시간 계산 가능성을 확인하였다. Launch Acceptability Region(LAR) means an area for successfully hitting the target. And LAR should be calculated in real time on aircraft so that LAR can be seen by pilot. LAR can be changed by the launch condition of the bomb, the impact condition of the target, and the atmospheric condition at the time of flight of the bomb. In this paper, we propose the calculation method of LAR using Artificial Neural Network(ANN). The learning data was generated by changing each condition from existing LAR model, and LAR model was derived through ANN learning. We confirmed the accuracy of the new LAR model by comparing the difference between the result data of existing LAR model and the new LAR model. And we confirmed the possibility of real time calculation of the LAR model on the aircraft by comparing the calculation time.

Understanding Disease Susceptibility through Population Genomics

Han, Seonggyun,Lee, Junnam,Kim, Sangsoo Korea Genome Organization 2012 Genomics & informatics Vol.10 No.4

Genetic epidemiology studies have established that the natural variation of gene expression profiles is heritable and has genetic bases. A number of proximal and remote DNA variations, known as expression quantitative trait loci (eQTLs), that are associated with the expression phenotypes have been identified, first in Epstein-Barr virus-transformed lymphoblastoid cell lines and later expanded to other cell and tissue types. Integration of the eQTL information and the network analysis of transcription modules may lead to a better understanding of gene expression regulation. As these network modules have relevance to biological or disease pathways, these findings may be useful in predicting disease susceptibility.

Nationwide concentration distributions of N-nitrosamines and secondary amines in chlorinated drinking water

Sungjin Jung,Sunyoung Park,Seonggyun Lee,Hekap Kim 한국분석과학회 2017 학술대회논문집 Vol.2017 No.11

Round-patterned ZnO nanostructure coated with siloxane-based polymer for nerve agent detection

Choi, Hyun Ji,Lee, Ji Won,Jeong, Dong-Cheol,Ha, Seonggyun,Song, Changsik,Boo, Jin-Hyo Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.429 No.-

<P><B>Abstract</B></P> <P>The alignment of zinc oxide (ZnO) nanostructures is expected to improve device sensitivities due to large surface areas which can be utilized to capture significant quantities of gas particles. In this study, we investigated patterned ZnO nanorods modified with polystyrene monolayers synthesized directly onto a quartz crystal microbalance (QCM) cell to increase the coating surface area of the sensing material. Also, we designed and synthesized a siloxane-based polymer (S1 polymer) as a sensing material. The patterned ZnO nanorods coated with S1 polymers were fabricated and used for the detection of dimethyl methylphosphonate (DMMP). The resonance frequency of QCM was shifted due to the adsorption and desorption of a compound at the surface of the modified electrodes. We have synthesized an S1 polymer that exhibited high sensitivity to DMMP. The patterned ZnO nanorods coated with the polymer also exhibited improved sensitivity due to an enhanced surface area capable of adsorbing more DMMP vapor.</P> <P><B>Highlights</B></P> <P> <UL> <LI> In this experiment, we investigated nanostructures by adjusting the diameter of the arranged ZnO nanorods according to PS spheres of various sizes. </LI> <LI> We have designed and synthesized a siloxane-based polymer as a sensing material. </LI> <LI> To evaluate its specific adsorbing properties, a flat S1 polymer and patterned ZnO nanostructures assisted with PS were prepared on QCM for sensing DMMP. </LI> <LI> We demonstrated that the patterned ZnO nanostructures could effectively adsorb gas particles within a short period of time. </LI> <LI> It was concluded that patterned ZnO nanostructures assisted with PS 800 nm among the three sizes of PS spheres most effectively improved the sensitivity of QCM. </LI> </UL> </P>

UV-mediated synthesis of pNIPAM-crosslinked double-network alginate hydrogels: Enhanced mechanical and shape-memory properties by metal ions and temperature

Choi, Eun Jung,Ha, Seonggyun,Lee, Jookyeong,Premkumar, Thathan,Song, Changsik Butterworth Scientific Ltd. etc. 2018 Polymer Vol. No.

<P><B>Abstract</B></P> <P>Allyl-substituted alginate (Alg) underwent gelation with <I>N</I>-isopropylacrylamide (NIPAM) monomers via UV-mediated radical reactions, resulting in a multi-responsive double-network hydrogel. The amount of NIPAM available for crosslinking affected several properties of the resulting Alg-NIPAM hydrogels. As more NIPAM was incorporated, the volume phase transition temperature (VPTT) and swelling properties of the Alg-NIPAM hydrogels decreased. Metal-ion addition caused increased crosslinking of the Alg-NIPAM hydrogels, allowing shape-memory of the materials due to their dual responsiveness to temperature and metal ions. Additional crosslinking caused the hydrogels to become stiffer, showing the ability to regulate the mechanical properties of the hydrogels. As a proof-of-concept, reversible shape changes under temperature and ionic cycling were demonstrated.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We prepared multi-responsive hydrogel via UV-mediated radical polymerization. </LI> <LI> Swelling properties and mechanical properties of hydrogel were controlled by temperature and metal ions. </LI> <LI> The shape of hydrogel deformed and recovered as temperature and metal ions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Dynamic Covalent Hydrazone Supramolecular Polymers toward Multiresponsive Self-Assembled Nanowire System

Kim, Kyung-su,Cho, Hye Jin,Lee, Jookyeong,Ha, Seonggyun,Song, Sun Gu,Kim, Seunghun,Yun, Wan Soo,Kim, Seong Kyu,Huh, Joonsuk,Song, Changsik American Chemical Society 2018 Macromolecules Vol.51 No.20

<P>Stimuli-responsive polymeric systems are of considerable interest due to their potential applications in environment-adaptive technologies such as smart surfaces. Traditionally, such systems can be constructed either by dynamic noncovalent (supramolecular) or dynamic covalent chemistry, but the use of both chemistries in one system may offer unique opportunities for structural diversity and various controllability. Herein, we report that hydrazone-pyridinum conjugates, which can be dynamically exchanged by transimination, assemble to form one-dimensional nanowires due to <I>direct intermolecular interactions</I> (without metal-ion coordination). The self-assembly process can be controlled not only by dynamic covalent chemistry but also by pH adjustment. The hydrazone-pyridinum conjugates are transformed to merocyanine-type dyes of distinctive negative solvatochromism via deprotonation, which also affects their self-assembly. Such a dual control of the dynamic molecular assembly will provide unique way to develop diverse smart nanomaterials with multistimuli-responsiveness.</P> [FIG OMISSION]</BR>