Click Synthesis of Hydrogels by Metal-Free 1,3-Dipolar Cycloaddition Reaction Between Maleimide and Azide Functionalized Polymers

Hong-Zheng Zhu,Gang Wang,Hong-Liang Wei,Hui-Juan Chu,Jing Zhu 한국고분자학회 2016 Macromolecular Research Vol.24 No.9

Herein, a metal-free 1,3-dipolar cycloaddition click reaction was used to prepare hydrogels. First, copolymer of N,N-dimethylacrylamide and 2-hydroxyethyl methacrylate was synthesized via free radical copolymerization with an initiator of 2,2'-azobisisobutyronitrile and a solution of 1,4-dioxane. Second, maleimide-functionalized polymer was obtained by a coupling reaction of the above synthesized copolymer and N-maleoyl alanine with a dehydrating agent of N,N'-dicyclohexylcarbodiimide. Similarly, azido-modified polymer was prepared by the reaction between azidoacetic acid and the as-prepared copolymer. Third, the hydrogels were obtained by the reaction of the azidomodified polymer and maleimide-functionalized copolymer without any initiator or catalyst. Gelation times of different conditions were measured by a cuvette inversion method. The samples of different steps were analysized by means of FTIR, NMR, SEM, etc. The swelling behaviour of the gels was investigated via a general gravimetric method. Finally, release mechanism was explored with a model drug molecule of 5-fluorouracil. It was found temperature, concentration and solvent had an impact on the gelation time. And the swelling behavior and drug-controlled release profiles of the hydrogels were relevant to the concentration of polymers used for the hydrogels.

Reversion of Multidrug Resistance by SKI-II in SGC7901/DDP Cells and Exploration of Underlying Mechanisms

Zhu, Zu-An,Zhu, Zheng-Qiu,Cai, Hong-Xing,Liu, Ying Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

In order to investigate whether SKI-II could reverse drug resistance and its possible mechanisms, we treated SGC7901/DDP cells with SKI-II or SKI-II in combination with DDP. Then cell growth, apoptosis, micromorphological changes, and expression of SphK1, P-gp, NF-${\kappa}B$, Bcl-2 and Bax were assessed by MTT assay, flow cytometry, electron microscopy, immunocytochemistry and Western blot assay respectively. SGC7901/DDP cells were insensitive to cisplatin 2.5mg/L, but when pretreated with SKI-II, their proliferation was inhibited by cisplatin 2.5mg/L significantly, the inhibition rate increasing with time and dose. The apoptosis rate was also significantly elevated. Expression of SphK1 and P-gp was decreased significantly, Pearson correlation analysis showing significant correlation between the two (r=0.595, P<0.01). Expression of NF-${\kappa}B$ and Bcl-2 was decreased significantly,while that of Bax was increased, compared to the control group. There were significant correlations between SphK1 and NF-${\kappa}B$(r=0.723, P<0.01), NF-${\kappa}B$ and Bcl-2(r=0.768, P<0.01). All these data indicated that SKI-II could reverse drug resistance of SGC7901/DDP to cisplatin by down-regulating expression of P-gp and up-regulating apoptosis through down-regulation of SphK1. The increased apoptotic sensitivity of SGC7901/DDP to cisplatin was due to the decreasing proportion of Bcl-2/Bax via down-regulating NF-${\kappa}B$.

Combining a HMM with a Genetic Algorithm for the Fault Diagnosis of Photovoltaic Inverters

Hong Zheng,Ruoyin Wang,Wencheng Xu,Yifan Wang,Wen Zhu 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

The traditional fault diagnosis method for photovoltaic (PV) inverters has a difficult time meeting the requirements of the current complex systems. Its main weakness lies in the study of nonlinear systems. In addition, its diagnosis time is long and its accuracy is low. To solve these problems, a hidden Markov model (HMM) is used that has unique advantages in terms of its training model and its recognition for diagnosing faults. However, the initial value of the HMM has a great influence on the model, and it is possible to achieve a local minimum in the training process. Therefore, a genetic algorithm is used to optimize the initial value and to achieve global optimization. In this paper, the HMM is combined with a genetic algorithm (GHMM) for PV inverter fault diagnosis. First Matlab is used to implement the genetic algorithm and to determine the optimal HMM initial value. Then a Baum-Welch algorithm is used for iterative training. Finally, a Viterbi algorithm is used for fault identification. Experimental results show that the correct PV inverter fault recognition rate by the HMM is about 10% higher than that of traditional methods. Using the GHMM, the correct recognition rate is further increased by approximately 13%, and the diagnosis time is greatly reduced. Therefore, the GHMM is faster and more accurate in diagnosing PV inverter faults.

Combining a HMM with a Genetic Algorithm for the Fault Diagnosis of Photovoltaic Inverters

Zheng, Hong,Wang, Ruoyin,Xu, Wencheng,Wang, Yifan,Zhu, Wen The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

The traditional fault diagnosis method for photovoltaic (PV) inverters has a difficult time meeting the requirements of the current complex systems. Its main weakness lies in the study of nonlinear systems. In addition, its diagnosis time is long and its accuracy is low. To solve these problems, a hidden Markov model (HMM) is used that has unique advantages in terms of its training model and its recognition for diagnosing faults. However, the initial value of the HMM has a great influence on the model, and it is possible to achieve a local minimum in the training process. Therefore, a genetic algorithm is used to optimize the initial value and to achieve global optimization. In this paper, the HMM is combined with a genetic algorithm (GHMM) for PV inverter fault diagnosis. First Matlab is used to implement the genetic algorithm and to determine the optimal HMM initial value. Then a Baum-Welch algorithm is used for iterative training. Finally, a Viterbi algorithm is used for fault identification. Experimental results show that the correct PV inverter fault recognition rate by the HMM is about 10% higher than that of traditional methods. Using the GHMM, the correct recognition rate is further increased by approximately 13%, and the diagnosis time is greatly reduced. Therefore, the GHMM is faster and more accurate in diagnosing PV inverter faults.

The Design of Malocclusion Model Diagnosis and Treatment Planning CAD System

Hong, Zhao,qiang, Zhai Zhan,Zheng, Wang Yu,Yie, Ke,Zhu, Lin 대한전자공학회 1992 HICEC:Harbin International Conference on Electroni Vol.1 No.1

Malocclusion model diagnosis and treatment is an important branch of stomatology. It means that dental diseases is treated through diagnosis and correction of dental deformity disease. In this paper, the objective, content, and method of malocclusion model diagnosis and treatment planning CAD system are introduced. Using the system, dentists are able to capture the image of dental cast, measure three dimensional feature points, extract specialized feature data, express teeth and gum with certain data structure, then provide the basis for design of treatment scheme. According to the feature points the feature data, computer aided design and simulation can be performed. The working efficiency and treatment effectivity of dentists can be improved in consequence.

White-light crosslinkable milk protein bioadhesive with ultrafast gelation for first-aid wound treatment

Zhu Qinchao,Zhou Xuhao,Zhang Yanan,Ye Di,Yu Kang,Cao Wangbei,Zhang Liwen,Zheng Houwei,Sun Ziyang,Guo Chengchen,Hong Xiaoqian,Zhu Yang,Zhang Yajun,Xiao Ying,Valencak Teresa G.,Ren Tanchen,Ren Daxi 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background : Post-traumatic massive hemorrhage demands immediately available first-aid supplies with reduced operation time and good surgical compliance. In-situ crosslinking gels that are flexibly adapting to the wound shape have a promising potential, but it is still hard to achieve fast gelation, on-demand adhesion, and wide feasibility at the same time. Methods : A white-light crosslinkable natural milk-derived casein hydrogel bioadhesive is presented for the first time. Benefiting from abundant tyrosine residues, casein hydrogel bioadhesive was synthesized by forming di-tyrosine bonds under white light with a ruthenium-based catalyst. We firstly optimized the concentration of proteins and initiators to achieve faster gelation and higher mechanical strength. Then, we examined the degradation, cytotoxicity, tissue adhesion, hemostasis, and wound healing ability of the casein hydrogels to study their potential to be used as bioadhesives. Result : Rapid gelation of casein hydrogel is initiated with an outdoor flashlight, a cellphone flashlight, or an endoscopy lamp, which facilitates its usage during first-aid and minimally invasive operations. The rapid gelation enables 3D printing of the casein hydrogel and excellent hemostasis even during liver hemorrhage due to section injury. The covalent binding between casein and tissue enables robust adhesion which can withstand more than 180 mmHg blood pressure. Moreover, the casein-based hydrogel can facilitate post-traumatic wound healing caused by trauma due to its biocompatibility. Conclusion : Casein-based bioadhesives developed in this study pave a way for broad and practical application in emergency wound management.

부산시민공원의 봄철 식물군락 색채 연구

정호남(ZHENG XIANHENG),왕홍(WANG HONG),주현달(ZHU XIANDA),조정형(Cho Joung hyung) 한국색채학회 2023 한국색채학회 학술대회 Vol.2023 No.4

식물 군락은 공원의 주요 구성 요소 중 하나이며 색채는 식물 군락의 아름다움을 향상시키는 데 중요한 역할을 한다. 본 연구에서는 부산시민공원의 식물경관 군락의 색채를 대상으로 현장조사를 통해 식물 군락 사진을 얻은 후 BIB-LCJ법과 SD법을 이용하여 설문조사를 실시하였다. 조사 데이터를 분석한 후 색채가 우수한 6개의 식물 군락을 결정하고 QTCCOLOR을 이용하여 이 우수한 색채를 가진 6개의 식물 군락 사진에 대해 색채를 추출하여 식물 색채의 HSB(HSV)값을 얻었다. 분석 결과는 다음과 같다. 첫째, 봄철의 밝고 따뜻한 색채가 사람들에게 새로운 느낌을 줄 수 있다. 둘째, 따뜻한 색채의 식물과 물의 조합은 수변 식물 군락의 경관적 아름다움을 높여주었다. 셋째, 다양한 색채의 현장 배치로 시민들의 봄에 대한 체험감을 높였다. 이 공원의 식물 군락 색채 디자인은 매우 좋은 모범 사례이며 이 연구가 도시 공원 식물 군락 색채 디자인을 위한 참고 자료가 될 수 있기를 바란다.

Hexadecylamine Modified Copper Nanowire Coated Superhydrophobic Cotton Fabric for Antifouling, Oil-water Separation, and Infrared Reflection Applications

Jiaojiao Zheng,Hong Zhang,Tianyu Cao,Yuanyuan Zhu,Lizhong He,Jianwei Li,Xudong Chen,Yinhu Qu 한국섬유공학회 2022 Fibers and polymers Vol.23 No.10

Superhydrophobic surfaces by creating surface roughness followed by coating with low-surface-energyfluorinated materials have been intensively developed on cotton fabrics. However, exploring superhydrophobic surfaces withnon-fluorine components and further improving their attachment with cotton fabrics is still challenging. Herein, wedeveloped a superhydrophobic surface on cotton fabric by dip coating with hexadecylamine (HDA) modified coppernanowires (Cu NWs) based on the coordination between Cu atoms and amine groups. The HDA modified Cu NWs not onlycreated surface roughness, but also decreased the surface energy, leading to a superhydrophobic cotton fabric with watercontact angle of 164 °±2.0 °. Furthermore, ultrasonic washing and tape peeling tests exhibited the Cu NWs were adheredtightly to the surface of cotton fibers, owing to the strong hydrogen bond between amine groups on HDA molecules andhydroxyl groups on cotton fibers. In addition, the superhydrophobic cotton fabric showed excellent antifouling, oil-waterseparation and infrared reflection properties. It is believed that this facile method provide promising industrial applicationsfor fabricating superhydrophobic surfaces on other substrates.

No Association Between Tea Consumption and Risk of Renal Cell Carcinoma: A Meta-analysis of Epidemiological Studies

Hu, Zheng-Hui,Lin, Yi-Wei,Xu, Xin,Chen, Hong,Mao, Ye-Qing,Wu, Jian,Xu, Xiang-Lai,Zhu, Yi,Li, Shi-Qi,Zheng, Xiang-Yi,Xie, Li-Ping Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Objective: To evaluate the association between tea consumption and the risk of renal cell carcinoma. Methods: We searched PubMed, Web of Science and Scopus between 1970 and November 2012. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Results: Twelve epidemiological studies (ten case-control studies and two cohort studies) were included in the final analysis. In a meta-analysis of all included studies, when compared with the lowest level of tea consumption, the overall relative risk (RR) of renal cell carcinoma for the highest level of tea consumption was 1.03 (95% confidence interval [CI] 0.89-1.21). In subgroup meta-analyses by study design, there was no significant association between tea consumption and renal cell carcinoma risk in ten case-control studies using adjusted data (RR=1.08, 95% CI 0.84-1.40). Furthermore, there was no significant association in two cohort studies using adjusted data (RR=0.95, 95% CI 0.81-1.12). Conclusion: Our findings do not support the conclusion that tea consumption is related to decreased risk of renal cell carcinoma. Further prospective cohort studies are required.

Genetic Polymorphisms of Glutathione S-transferase M1 and Prostate Cancer Risk in Asians: A Meta-analysis of 18 Studies

Hu, Zheng-Hui,Lin, Yi-Wei,Xu, Xin,Chen, Hong,Mao, Ye-Qing,Wu, Jian,Zhu, Yi,Xu, Xiang-Lai,Xie, Li-Ping Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Background: Many studies have investigated associations between the glutathione S-transferase M1 (GSTM1) null polymorphism and risk of prostate cancer, but the impact of GSTM1 in people who live in Asian countries is still unclear owing to inconsistencies across results. Methods: We searched the PubMed, Web of Science, Scopus, Ovid and CNKI databases for studies of associations between the GSTM1 null genotype and risk of prostate cancer in people who live in Asian countries, and estimated summary odds ratios (ORs) with 95% confidence intervals (95% CIs). Results: A total of 18 case-control studies with 2,172 cases and 3,258 controls were included in this meta-analysis, which showed the GSTM1 null genotype to be significantly associated with increased risk of prostate cancer in people who live in Asian countries (random-effects OR=1.74, 95% CI1.44-2.09, P<0.001). Similar results were found in East Asians (OR=1.41; 95% CI: 1.12-1.78; P=0.004) and Caucasians in Asia (OR=2.19; 95% CI: 1.85-2.60; P<0.001). No evidence of publication bias was observed. Conclusions: This meta-analysis of available data suggested that the GSTM1 null genotype does contribute to increased risk of prostate cancer in people who live in Asian countries.