A large-area free-standing graphene oxide multilayer membrane with high stability for nanofiltration applications

Chen, Long,Li, Yanhui,Chen, Lina,Li, Na,Dong, Chenglong,Chen, Qiong,Liu, Beibei,Ai, Qing,Si, Pengchao,Feng, Jinkui,Zhang, Lin,Suhr, Jonghwan,Lou, Jun,Ci, Lijie Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.345 No.-

<P><B>Abstract</B></P> <P>A flexible and free-standing graphene oxide and nylon 6 (GO@nylon 6) multilayer nanofiltration membrane was prepared by a layer-by-layer assembly process. The combination of electrospinning and electrospraying technique was employed, which can facilely prepare large-area membrane with size of 20 × 30 cm. The mechanical stability of multilayer membrane has enhanced significantly due to the tightly locked structure achieved by nylon 6 nanofibers network. The novel GO@nylon 6–13 multilayer nanofiltration membrane demonstrated a pure water flux up to 11.15 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP>, while keeping high organic dye rejection rate (>95% for methylene blue, and >99% for methyl orange). The rejections rate of the Na<SUB>2</SUB>SO<SUB>4</SUB>, NaCl, CuSO<SUB>4</SUB>, and Pb(NO<SUB>3</SUB>)<SUB>2</SUB> were 56.5%, 27.6%, 36.7%, and 18.9%, respectively. Furthermore, GO@nylon 6–13 multilayer nanofiltration membrane also demonstrated a high flux of some common organic solvents (8.4, 5.3, and 0.8 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP> for methanol, ethanol, and NMP, respectively), showing excellent chemical stability for separation process in those solvents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Large-area GO@nylon 6 multilayer nanofiltration membrane was prepared. </LI> <LI> The multilayer structure enhances the mechanical stability. </LI> <LI> The multilayer membrane demonstrates a high water flux. </LI> <LI> The multilayer membrane shows high rejection rate for organic dyes. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Photograph and cross-section SEM image of GO@nylon 6 multilayer nanofiltration membrane, the inset shows the water contact angle.</P> <P>[DISPLAY OMISSION]</P>

Expression and Detection of Retinol-Binding Protein-4 Gene of Pig in E. coli

LiNa Sun,WanHong Li,ShuXiong Chen,Chao Chen,XiaoFeng Hou,Yun Zhao,Lu Chen,ChunJin Li,Xu Zhou 한국동물생명공학회(구 한국동물번식학회) 2014 한국동물번식학회 한중일 심포지엄 Vol.2014 No.1

Retinol-Binding Protein-4 (RBP-4) is a low molecular weight lipocalin, which mainly functions as a carrier for vitamin A. Though liver is the main machinery for synthesis of this protein, it is also detectable in other extrahepatic tissues, for example, ovary, uterus, and placenta. Recent evidences have shown that RBP-4 plays important roles in animal reproduction, for example, promoting the development of uterus and embryo. To the best of our knowledge, our laboratory firstly reported that high level of RBP-4 existed in follicular fluid from follicular cysts in sows. Moreover, we have also found that RBP-4 could be secreted by granulosa cells, and RBP-4 receptor was detected in granulosa cells. However, there is no any evidence on the role of RBP-4 in regulating the follicular development. Therefore, cloning and expression of RBP-4 and preparation of polyclonal antibody could help us to explore the role of RBP-4 in follicular development. The aim of this work was to construct prokaryotic expression system of swine RBP-4 gene. The total RNA was extracted from swine’s normal ovarian tissue. The sequence including the whole length of RBP-4 was amplified by RT-PCR and inserted into pEASY-E1.Then transformed into E. coli BL21(DE3)pLysS after gene sequencing. Three hours later, adding IPTG with the final concentration of 1mmol/L and inducing five hours. After centrifugation, the supernatant was discarded. By adding Glucose to Luria-Bertani broth, the expressions of protein were increased. SDS-PAGE showed that the RBP-4 gene expressed in the form of inclusion body with a molecular weight of 21KD. Western-Blot results showed that the target protein could be specifically recognized by mouse anti-human monoclonal antibody. Prokaryotic expression vector of RBP-4 gene was successfully established, and the gene was successfully expressed n E. coli, which is ready for purification and RBP-4 polyclone antibody. Meanwhile, these results were beneficial to investigate the function of RBP-4 in follicular development.

Comparative Study of Basic Education Reform in South Korea and the “Double Reduction” Policy in China

Li Lina 국민대학교 한반도미래연구원 2023 한반도미래연구 Vol.9 No.-

In the rapidly evolving global and information-driven era, education plays a crucial role in societal development. Basic education, being the core of the educational system, significantly impacts national progress and the quality of people's lives. South Korea's basic education reforms aim to enhance student learning outcomes and reduce academic burdens. In contrast, China's “Double Reduction” policy seeks to alleviate students' academic and extracurricular burdens and promote educational equity, adapting to the demands of the times. The policy also encourages student participation in extracurricular activities and social practices, fostering comprehensive qualities and a sense of social responsibility. Furthermore, the “Double Reduction” policy emphasizes communication and cooperation between schools and families, focusing jointly on student growth and development. A comparison of South Korea's basic education reforms and China's“Double Reduction”policy reveals differences in their objectives and approaches. Against this backdrop, many countries are reforming education to meet contemporary needs. South Korea, known for its strong educational system, offers valuable insights into basic education reform compared to other countries. This text aims to explore the similarities and differences between the basic education reforms in South Korea and China's “Double Reduction” policy. It further investigates whether the merits of South Korean educational reforms can be integrated into China's “Double Reduction” policy, offering valuable insights for future educational reforms in China. By conducting a comparative and in-depth analysis of the educational reform policies in South Korea and China, this study holds fundamental significance for researchers in the related fields. 급변하는 글로벌 및 정보화 시대에서 교육은 사회 발전에서 중요한 역할을 하고 있었다. 교육 시스템의 핵심인 기초 교육은 국가 발전과 사람들의 삶의 질에 큰 영향을 미친다. 대한민국의 기초 교육 개혁은 주로 학생 학습 성과 향상과 학업 부담감소를 목표로 하고 있다. 그와 대조적으로 중국의 “이중 감축” 정책은 학생들의 학업 및 학외 부담을 경감하고 교육 평등을 증진하며 현대적인 요구에 대응하고자 한다. 이 정책은 학생들의 학업 이외 활동 및 사회 참여를 촉진하여 종합적인 능력과 사회 책임감을 함양하였다. 더불어 “이중 감축” 정책은 학교와 가족 간의 소통과 협력을 강조하여 학생의 성장과 발전을 공동으로 추구한다. 대한민국의 기초 교육 개혁과 중국의 “이중 감축” 정책을 비교하면 그 목표와 방법에 차이가 있음을 확인할 수 있다. 이러한 맥락에서 많은 국가가 교육을 현대적인 요구에 맞추기 위해 개혁하고 있다. 대한민국은 강력한 교육 체계로 잘 알려져 있어 다른 국가들과 비교하여 기초 교육 개혁에 대한 소중한 통찰력을 제공할 수 있다. 본 텍스트는 대한민국의 기초 교육 개혁과 중국의 “이중 감축” 정책 간 유사점과 차이점을 탐구하고, 대한민국 교육 개혁의 장점이 중국의 “이중 감축” 정책에 어떻게 통합될 수 있는지에 대한 연구이다. 대한민국과 중국의 교육 개혁 정책을 비교적이고 심층적으로 분석함으로써, 본 연구는 관련 분야의 연구자들에게 기본적인 의미를 제공할 것이다.

Cloning and analysis of the molecularly characterized chitinase genes of Daphnia carinata and Simocephalus vetulus

Lina Li,Yaling Chen,Jinsong Bao,Shaonan Li 한국유전학회 2017 Genes & Genomics Vol.39 No.12

Daphniidae plays an important role in maintaining the integrity and sustainability of food chains of freshwater ecosystems. However, studies on the intact genes of chitinase in Daphniidae have not been carried out till date. In this study, we obtained the full-length complementary DNA (cDNA) from Daphnia carinata and Simocephalus vetulus, members of the Family Daphniidae, by rapid amplification of cDNA ends and polymerase chain reaction. The two cDNAs were named DcChi and SvChi, respectively. The result showed that DcChi and SvChi were 1404 and 1319 bp in length and they encoded 383 and 382 amino acids, respectively. Based on their cDNA sequences, the genomic structures of the two chitinases were characterized. Sequence analysis revealed that DcChi was composed of three exons and two introns, while SvChi had four exons and three introns. Based on the presence of conserved catalytic domain sequences, the two chitinases could be clustered within the same phylogenetic group. Homology analysis showed that the two deduced proteins had a high similarity (65–88%) to those from published species in Family Daphniidae and a low similarity to those from the species in Class Malacostraca Subclass Copepoda (38–42%) and those from the species in Class Insecta Order Diptera (33–38%). Based on the results of multiple alignments of chitinases, we designed peptides that were specific to chitinases from the Family Daphniidae. The quantitative real time PCR analysis indicated that the transcript level of the chitinase gene increased with the growth of the two species.

Identification of MicroRNAs as potential biomarkers for detecting ischemic stroke

Li Kexin,Shen Li,Zheng Pingping,Wang Yanjun,Wang Lijuan,Meng Xiaoli,Lv Yaogai,Xue Zhiqiang,Guo Xin,Zhang Anning,Pan Pan,Bi Chunli,Chen Yang,Feng Tianyu,Li Bo,Jin Lina,Yao Yan 한국유전학회 2022 Genes & Genomics Vol.44 No.1

Background: Increasing epidemic of ischemic stroke (IS) makes it urgent to understand the pathogenesis and regulatory mechanism, previous studies have described microRNAs (miRNAs) is part of the brain's response to ischemia. Objective: The aim of this study was to screen potential biomarkers for the prediction and novel treatment of IS. Methods: Differentially expressed miRNAs were screened from three newly diagnosed IS patients and three controls by RNA sequencing technology. Furthermore, target prediction databases were then used to analysis the target genes of different expressed miRNAs, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were used to identify the functions and the main biochemical and signal pathways of differentially expressed target genes. Results: Our results revealed that 27 miRNAs were differentially expressed in IS, among which, hsa-miR-659-5p was the most highly increased and was first found to be associated with IS. In addition, KEGG pathway analyses showed that differentially expressed miRNAs were mainly significantly enriched in lysosome pathway, cytokine-cytokine receptor interaction pathway, spliceosome pathway, base excision repair pathway. Conclusions: miRNAs were involved in IS pathogenesis, and hsa-miR-659-5p, hsa-miR-151a-3p and hsa-miR-29c-5p as the three highest |log2FoldChange| regulation in this study, which may be the biomarkers of IS and need further study.

Mithramycin A Inhibits Mouse Sertoli TM4 Cells Proliferation Involving Up-Regulation of INHA Expression

Wanhong Li,Yun Zhao,Zhuo Liu,Shuxiong Chen,Lina Sun,Hongjiao Li,Lu Chen,Chunjin Li,Xu Zhou 한국동물생명공학회(구 한국동물번식학회) 2014 한국동물번식학회 한중일 심포지엄 Vol.2014 No.1

A general and efficient method for decorating graphene sheets with metal nanoparticles based on the non-covalently functionalized graphene sheets with hyperbranched polymers.

Li, Haiqing,Han, Lina,Cooper-White, Justin J,Kim, Il RSC Pub 2012 Nanoscale Vol.4 No.4

<P>Multipyrene terminated hyperbranched polyglycidol (mPHP) has been synthesized and used to non-covalently functionalize pristine graphene sheets (GSs) through π-π stacking interactions. Mediated by the mPHP layer, a variety of metal nanoparticles (Au, Ag and Pt) were in situ generated and deposited onto the surface-modified GS, yielding versatile GS/mPHP/metal nanohybrids. As typical examples, by simply controlling the concentration of HAuCl(4) used, Au nanostructures ranging from isolated spheres to a continuous film were created and coated onto the surface-modified GS. The studies on the fluorescence properties of resulting GS/mPHP/Au hybrid nanostructures reveal that the GS and controllable content of Au components in the hybrids can effectively quench the fluorescence emission of mPHP in a controlled manner. Further investigation indicates that GS/mPHP/Au hybrids are promising surface enhanced Raman scattering (SERS) substrates. The SERS activities of these hybrids depend on the contents and form of the Au. The GS/mPHP/Au hybrid containing continuous Au films exhibits the strongest SERS activity. GS/mPHP/Au hybrids are also used as efficient heterogeneous catalysts for the reduction of 4-NP, and demonstrate excellent catalytic performance. The detailed reaction kinetics and the reusability of such catalysts have also been investigated.</P>

Energy Efficiency Optimization for Uplink Multiuser MIMO Systems

Lina Ma,Shuangzhi Li,Xiaomin Mu 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.8

To satisfy green communication needs, energy efficiency is regraded as one of the most important indicators to evaluate the effectiveness of a communication system. In this paper, we establish the energy efficiency optimization framework for uplink multiuser mutliple-input multiple-output system. Taking the circuit power, the antenna link power and signal processing power into consideration, an analytical expression of the achieveable energy efficiency is firstly established, which can better model the practical communication process. Furthermore, we simplify the objective function under some mild conditions. After demonstrating the existence of a unique golbally optimal energy efficiency, an adaptive water-filling power allocation algorithm is proposed to further improve the energey efficiency of the system. Finally some simulation results are given to verify the performance of our scheme. Our work can provide a fundamental principles for uplink mutiluser multiple-input multiple-output systems design.

Edge Computing-based Differential Positioning Method for BeiDou Navigation Satellite System

( Lina Wang ),( Linlin Li ),( Rui Qiu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.1

BeiDou navigation satellite system (BDS) is one of the four main types of global navigation satellite systems. The current system has been widely used by the military and by the aerospace, transportation, and marine fields, among others. However, challenges still remain in the BeiDou system, which requires rapid responses for delay-sensitive devices. A differential positioning algorithm called the data center-based differential positioning (DCDP) method is widely used to avoid the influence of errors. In this method, the positioning information of multiple base stations is uploaded to the data center, and the positioning errors are calculated uniformly by the data center based on the minimum variance or a weighted average algorithm. However, the DCDP method has high delay and overload risk. To solve these problems, this paper introduces edge computing to relieve pressure on the data center. Instead of transmitting the positioning information to the data center, a novel method called edge computing-based differential positioning (ECDP) chooses the nearest reference station to perform edge computing and transmits the difference value to the mobile receiver directly. Simulation results and experiments demonstrate that the performance of the ECDP outperforms that of the DCDP method. The delay of the ECDP method is about 500ms less than that of the DCDP method. Moreover, in the range of allowable burst error, the median of the positioning accuracy of the ECDP method is 0.7923m while that of the DCDP method is 0.8028m.

Insulin Resistance Is an Important Risk Factor for Cognitive Impairment in Elderly Patients with Primary Hypertension

Lina Ma,Yun Li,Ming Feng,Yuying Qian,Wei Yang,Jia Liu,Rui Han,Hong Zhu 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.1

Purpose: Insulin resistance plays a role in the development of dementia and hypertension. We investigated a possible relationship between cognitive impairment and insulin resistance in elderly Chinese patients with primary hypertension. Materialsand Methods: One hundred and thirty-two hypertensive elderly patients (>60 years) were enrolled in this study, and assigned into either the cognitive impairmentgroup (n=61) or the normal cognitive group (n=71). Gender, age, education,body mass index (BMI), waist hip ratio (WHR), total cholesterol (TC), triglyceride(TG), C-reactive protein (CRP), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), creatinine (Cr), fasting plasma glucose (FPG), fasting insulin (FINS), homeostasis model of assessment for insulin resistance index (HOMA-IR), systolic blood pressure, diastolic blood pressure, smoking history, atherosclerosis and the proportion of uncontrolled hypertensionwere compared between the two groups. Multi-factorial logistic regressionanalysis was performed. Results: No significant differences were found in gender, age, TC, CRP, HDL-C, LDL-C, Cr, BP, smoking history, atherosclerosis and the proportion of uncontrolled hypertension between the two groups. The cognitiveimpairment group had lower education levels, and higher BMI, WHR, TG, FPG, FINS, and HOMA-IR levels than the control group. Logistic regression analysis revealed the levels of education, BMI, WHR, and HOMA-IR as independentfactors that predict cognitive impairment in patients. Conclusion: Our study demonstrates that poor education and increased BMI, WHR, and HOMA-IR are independent risk factors for cognitive impairment in elderly patients with hypertension. Insulin resistance plays an important role in the development of cognitive impairment in primary elderly hypertensive patients.