Preparation of a highly sensitive graphene‑based sensor to investigate the effect of exercise on electrolytes in sweat in hot and humid environment

Jialin Han 한국탄소학회 2023 Carbon Letters Vol.33 No.7

In this study, we synthesized a reduced graphene oxide-manganese dioxide (rGO-MnO2) composite material using a one-step hydrothermal method and used it as a transducer layer in solid-state ion-selective electrodes (ISEs) for monitoring potassium and sodium ions in sweat. The rGO-MnO2 composite was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), revealing its unique surface morphology and crystalline structures. Electrochemical characterizations, including cyclic voltammetry (CV) and potential response testing, demonstrated the excellent performance of the rGO-MnO2 composite material as a transducer layer in ISEs. The fabricated electrodes displayed good linear responses to potassium and sodium ions, with a voltage response of 36.4 mV and 47.6 mV per unit concentration change, respectively. The electrodes also exhibited improved resistance to gas interference, such as O2, N2, and CO2. We utilized these ISEs to measure changes in potassium and sodium ion concentrations in sweat samples collected over nine days of exercise, demonstrating the practical application of the rGO-MnO2-based ISEs. This work highlights the potential of using graphene/metal oxide composites as solid contact materials in ISEs for cost-effective and stable ion sensing applications.

The Analysis of Beijing Tourism Destination Image Based on the Network Texts

Wu Jialin,Zheng Miao,Han Xu 한국무역전시학회 2021 무역전시연구 Vol.16 No.4

정보통신기술의 발달로 인해 잠재 관광객은 인터넷으로 여행 정보를 수집한다. 관광 객들은 온라인 플랫폼에서 여행과 관련된 계획, 전략 등을 포스팅하고 여행 경험을 공 유한다. 이러한 온라인 텍스트는 관광객의 경험과 느낌을 주관적으로 설명한다. 본 연 구는 이러한 텍스트를 기반으로 목적지 이미지를 분석하고자 하였다. 본 연구는 Ctrip.com에 게시된 여행 관련 텍스트 중 베이징의 사례를 수집하여 정리하였다. ROST CM6 소프트웨어를 사용하여 빈도가 높은 특징 단어를 추출하고, 네트워크 텍스트 분석 을 사용하여 베이징의 인지적 이미지, 정서적 이미지 및 추천의도를 분석하였다. 연구 결과, 관광객은 목적지의 관광명소에 대한 인지적 이미지가 가장 강하게 나타나 는 것으로 나타났다. 정서적 이미지는 관광객의 긍정적인 감정에 영향을 주지만, 추천 의도를 명확하게 나타내지는 않았다. 분석된 결과를 바탕으로 베이징의 관광지 이미지 제고를 위한 시사점을 제시하였다. With the development of internet, potential tourists began to search travel information of destination through the internet. At the same time, tourists also share their travel experiences by publishing travel notes and tips on online social platforms. These online texts from tourists describe their experiences and feelings of the destination from a subjective perspective, are also providing original data of destination image for researchers. This paper takes Beijing as a case study site, collected travel notes on Ctrip.com, used ROST CM6 to extract high-frequency feature words, and used network text analysis to analyze Beijing’s cognitive image, emotional image, and recommendation intentions. It can be found that the tourists have the strongest perception of the tourist attractions in the cognitive image, and shown a positive emotional image. Otherwise, the recommendation intention is not very clear. According to the results, relevant destination strategies to enhance the image of Beijing’s are proposed.

Potential Antitumor Activity of SIM-89 in Non-Small Cell Lung Cancer Cells

Jun Pei,Baohui Han,Tianqing Chu,Minhua Shao,Jiajun Teng,Huifang Sha,Aiqing Gu,Rong Li,Jialin Qian,Weifeng Mao,Ying Li 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.3

Purpose: c-Met and its ligand, hepatocyte growth factor (HGF), play a critical role in oncogenesis and metastatic progression. The aim of this study was to identify inhibited enzymogram and to test the antitumor activity of SIM-89 (a c-Met receptor tyrosine kinaseinhibitor) in non-small cell lung cancer. Materials and Methods: Z’-LYTE kinase assay was employed to screen the kinase enzymogram, and mechanism of action (MOA) analysis was used to identify the inhibited kinases. Cell proliferation was then analyzed by CCK8 assay, and cell migration was determinedby transwell assay. The gene expression and the phosphorylation of c-Met were examined by realtime-PCR and western blotting, respectively. Finally, the secretion of HGF was detected by ELISA assay. Results: c-Met, activated protein kinase (AMPK), and tyrosine kinase A (TRKA) were inhibited by SIM-89 with the IC50 values of 297 nmol/L, 1.31 μmol/L, and 150.2 nmol/L, respectively. SIM-89 exerted adenosine triphosphate (ATP) competitive inhibition on c-Met. Moreover, the expressions of STAT1, JAK1, and c-Met in H460 cells were decreased by SIM-89 treatment, and c-Met phosphorylationwas suppressed in A549, H441, H1299, and B16F10 cells by the treatment. In addition, SIM-89 treatment significantly decreased the level of HGF, which accounted for the activation of c-Met receptor tyrosine kinase. Finally, we showed cell proliferationinhibition and cell migration suppression in H460 and H1299 cells after SIM-89 treatment. Conclusion: In conclusion, SIM-89 inhibits tumor cell proliferation, migration and HGF autocrine, suggesting it’s potential antitumoractivity.

Identification and Characterization of a New Alkaline SGNH Hydrolase from a Thermophilic Bacterium Bacillus sp. K91

( Tingting Yu ),( Junmei Ding ),( Qingxia Zheng ),( Nanyu Han ),( Jialin Yu ),( Yunjuan Yang ),( Junjun Li ),( Yuelin Mu ),( Qian Wu ),( Zunxi Huang ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.4

est19 is a gene from Bacillus sp. K91 that encodes a new esterase. A comparison of the amino acid sequence showed that Est19 has typical Ser-Gly-Asn-His (SGNH) family motifs and could be grouped into the SGNH hydrolase family. The Est19 protein was functionally cloned, and expressed and purified from Escherichia coli BL21(DE3). The enzyme activity was optimal at 60°C and pH 9.0, and displayed esterase activity towards esters with short-chain acyl esters (C2-C6). A structural model of Est19 was constructed using phospholipase A1 from Streptomyces albidoflavus NA297 as a template. The structure showed an α/β-hydrolase fold and indicated the presence of the typical catalytic triad Ser49-Asp227-His230, which were further investigated by site-directed mutagenesis. To the best of our knowledge, Est19 is a new member of the SGNH hydrolase family identified from thermophiles, which may be applicable in the industrial production of semisynthetic β-lactam antibiotics after modification.

The Complete Genome Sequence of Southern rice black-streaked dwarf virus Isolated from Vietnam

Dinh, Thi-Sau,Zhou, Cuiji,Cao, Xiuling,Han, Chenggui,Yu, Jialin,Li, Dawei,Zhang, Yongliang The Korean Society of Plant Pathology 2012 Plant Pathology Journal Vol.28 No.4

We determined the complete genome sequence of a Vietnamese isolate of Southern rice black-streaked dwarf virus (SRBSDV). Whole genome comparisons and phylogenetic analysis showed that the genome of the Vietnamese isolate shared high nucleotide sequence identities of over 97.5% with those of the reported Chinese isolates, confirming a common origin of them. Moreover, the greatest divergence between different SRBSDV isolates was found in the segments S1, S3, S4 and S6, which differs from the sequence alignment results between SRBSDV and Rice black streaked dwarf virus (RBSDV), implying that SRBSDV evolved in a unique way independent of RBSDV. This is the first report of a complete nucleotide sequence of SRBSDV from Vietnam and our data provides new clues for further understanding of molecular variation and epidemiology of SRBSDV in Southeast Asia.

The Complete Genome Sequence of Southern rice black-streaked dwarf virus Isolated from Vietnam

Thi-Sau Dinh,Cuiji Zhou,Xiuling Cao,Chenggui Han,Jialin Yu,Dawei Li,Yongliang Zhang 한국식물병리학회 2012 Plant Pathology Journal Vol.28 No.4

We determined the complete genome sequence of a Vietnamese isolate of Southern rice black-streaked dwarf virus (SRBSDV). Whole genome comparisons and phylogenetic analysis showed that the genome of the Vietnamese isolate shared high nucleotide sequence identities of over 97.5% with those of the reported Chinese isolates, confirming a common origin of them. Moreover, the greatest divergence between different SRBSDV isolates was found in the segments S1, S3, S4and S6, which differs from the sequence alignment results between SRBSDV and Rice black streaked dwarf virus (RBSDV), implying that SRBSDV evolved in a unique way independent of RBSDV. This is the first report of a complete nucleotide sequence of SRBSDV from Vietnam and our data provides new clues for further understanding of molecular variation and epidemiology of SRBSDV in Southeast Asia.