Solution Synthesis of Copper Microflowers

Guo Bin Cheng 대한금속재료학회 ( 구 대한금속학회 ) 2009 ELECTRONIC MATERIALS LETTERS Vol.5 No.4

Copper microflowers composed of many thin nanopetals have been successfully synthesized on a large scale by the reaction of CuCl2 with N2H4 in the presence of sodium tartrate as the complexing reagent and cetyl-trimethylammonium bromide (CTAB) as surfactant. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and a UV-vis spectrum. The results indicate that the amount of CTAB has a great effect on the shape of the resultant copper products. Only copper nanoparticles can be obtained without a surfactant while irregular flower-like microstructures with very thick petals can be produced with large amounts of CTAB.

Bending of a rectangular plate resting on a fractionalized Zener foundation

Cheng-Cheng Zhang,Hong-Hu Zhu,Bin Shi,Guo-Xiong Mei 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.6

The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelasticelastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in termsof the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the timedependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plateperformance over many decades of time.

Bending of a rectangular plate resting on a fractionalized Zener foundation

Zhang, Cheng-Cheng,Zhu, Hong-Hu,Shi, Bin,Mei, Guo-Xiong Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.6

The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelastic-elastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in terms of the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the time-dependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plate performance over many decades of time.

Study on the Magnetic Rate Sensitivity and Shear Properties of Magnetorheological Shear Thickening Fluid

Guo-Jun Yu,Shao-Jie Zhu,Cheng-Bin Du,Ling-Yun Wang,Jun-Chi Huang 한국자기학회 2023 Journal of Magnetics Vol.28 No.3

This paper studies magnetic field control and velocity-activated magnetorheological shear thickening fluid (MR-STF). High-concentration STF is composed of nano-sized silica particles suspended in a solvent polyethylene glycol (PEG), and then micron-sized carbonyl iron particles of different mass fractions are added to the STF to manufacture different MR-STF. The rheometer is used to study the viscoelasticity of all four samples. The correlation between dynamic behavior and shear rate, angular frequency, and external magnetic field is studied and discussed. In the lower angular frequency range, the loss modulus is slightly larger than the storage modulus, and MR-STF behaves as a viscoelastic state. After the critical angular frequency, the storage modulus decreases sharply, well below the loss modulus. MR-STF appears in a viscous state and a liquid state. With the start of external field excitation, MR-STF is more inclined to MRF. Finally, the apparent viscosity and shear rate of MR-STF are fitted. The results show that with the increase of magnetic induction strength, the plastic viscosity coefficient of MR fluid increases, the flow characteristic index decreases, and the shear thinning effect becomes more significant.

Chinese herbal injections for coronavirus disease 2019 (COVID-19): A narrative review

Xiao-Bin Zhu,Meng Guo,Zhi-Hui Zhang,Li-Hua Sun,Lei Liu,Li-Juan Zhou,Chun-Lei Shan,Yi Yang,Lian-Di Kan,Liu-Cheng Li 한국한의학연구원 2021 Integrative Medicine Research Vol.10 No.4

Background The outbreak of Coronavirus disease 2019 (COVID-19) has caused more than 180 million infections and 3.9 million deaths. To date, emerging clinical evidence has shown the synergetic benefits of Chinese herbal injections in treating this contagious respiratory disease. This review aims to summarize and analyze the efficacy and safety of Chinese herbal injections in the therapy of COVID-19. Methods The literature from 3 electronic databases, PubMed, CNKI, and Web of Science, were searched using the search terms “COVID-19”, “SARS-CoV-2”, “traditional Chinese medicine”, “herb”, “herbal”, and “injection”. Then the identified articles were comprehensively evaluated. Results Limited data demonstrated that Chinese herbal injections could significantly improve the clinical outcomes of COVID-19 patients, especially in combination with conventional treatment strategies. The benefits of which were mainly associated with the relief of symptoms, prevention of secondary infection, regulation of inflammation and immune function. There was also evidence showing the inhibitory effects on SARS-CoV-2 replication in vitro. Nevertheless, available real-world data suggested the increased risk of adverse event. Furthermore, the defects of existing researches and the insights for discovering novel antiviral drugs were prospectively discussed. Conclusion Evidence-based advances revealed that Chinese herbal injections such as XueBiJing injection and ShenMai injection, exerted potent effects against COVID-19. Further laboratory researches and clinical evaluation are needed to gather scientific evidence on the efficacy and safety.

Sensory involvement in the SOD1-G93A mouse model of amyotrophic lateral sclerosis

Yan-Su Guo,Dong-Xia Wu,Hong-Ran Wu,Shu-Yu Wu,Cheng Yang,Bin Li,Hui Bu,Yue-sheng Zhang,Chun-Yan Li 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.3

A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALSlike disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage. We report herein that the spinal cords of mice expressing a human SOD1 mutant (hSOD1-G93A), besides showing typical destruction of motor neurons and axons, exhibit significant damage in the sensory system, including Wallerian-like degeneration in axons of dorsal root and dorsal funiculus, and mitochondrial damage in dorsal root ganglia neurons. Thus, hSOD1-G93A mutation causes both motor and sensory neuropathies, and as such the disease developed in the transgenic mice very closely resembles human ALS. A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALSlike disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage. We report herein that the spinal cords of mice expressing a human SOD1 mutant (hSOD1-G93A), besides showing typical destruction of motor neurons and axons, exhibit significant damage in the sensory system, including Wallerian-like degeneration in axons of dorsal root and dorsal funiculus, and mitochondrial damage in dorsal root ganglia neurons. Thus, hSOD1-G93A mutation causes both motor and sensory neuropathies, and as such the disease developed in the transgenic mice very closely resembles human ALS.

A Report of Chigger Mites on the Striped Field Mouse, Apodemus agrarius, in Southwest China

Yan-Ling Chen,Xian-Guo Guo,Tian-Guang Ren,Lei Zhang,Rong Fan,Cheng-Fu Zhao,Zhi-Wei Zhang,Ke-Yu Mao,Xiao-Bin Huang,Ti-Jun Qian 대한기생충학열대의학회 2021 The Korean Journal of Parasitology Vol.59 No.6

Disease vector occurrence and ecological characteristics of chiggers on the chestnut white-bellied rat Niviventer fulvescens in Southwest China between 2001 and 2019

Yan-Ling Chen,Xian-Guo Guo,Wen-Yu Song,Tian-Guang Ren,Lei Zhang,Rong Fan,Cheng-Fu Zhao,Zhi-Wei Zhang,Wenge Dong,Xiao-Bin Huang,Dao-chao Jin 대한기생충학ㆍ열대의학회 2023 The Korean Journal of Parasitology Vol.61 No.3

Chigger mites are the vector of scrub typhus. This study estimates the infestation status and ecological characteristics of chiggers on the chestnut white-bellied rat Niviventer fulvescens in Southwest China between 2001 and 2019. Chiggers were identified under the microscope, and infestation indices were calculated. The Preston’s log-normal model was used to fit the curve of species abundance distribution. A total of 6,557 chiggers were collected in 136 of 342 N. fulvescens rats, showing high overall infestation indices (prevalence=39.8%, mean abundance=19.2, mean intensity=48.2) and high species diversity (S =100, H’=3.0). Leptotrombidium cangjiangense, Neotrombicula japonica, and Ascoschoengastia sifanga were the three dominant chigger species (constituent ratio=42.9%; 2,736/6,384) and exhibited an aggregated distribution among different rat individuals. We identified 100 chigger species, with 3 of them (Leptotrombidium scutellare, Leptotrombidium wenense, and Leptotrombidium deliense) as the main vectors of scrub typhus in China and nine species as potential vectors of this disease. Disease vector occurrence on N. fulvescens may increase the risk of spreading scrub typhus from rats to humans. Chigger infestation on N. fulvescens varied significantly in different environments. The species abundance distribution showed a log-normal distribution pattern. The estimated number of chigger species on N. fulvescens was 126 species.

Value of Postoperative Radiation Therapy for Regional Control after Dissection in Head and Neck Squamous Cell Carcinoma Cases

Li, Xiao-Ming,Di, Bin,Shang, Yao-Dong,Tao, Zhen-Feng,Cheng, Ji-Min,He, Zhan-Guo Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

Objective: We aimed to define clinicopathologic risk factors associated with regional recurrence (RR) and thus the effectiveness of postoperative radiotherapy (PORT) for neck control for head and neck squamous cell carcinomas (HNSCCs) with differing cervical lymph node status. Methods: A retrospective study was performed in 196 HNSCC patients with pathologically positive neck node (N+) to evaluate the high-risk factors for RR and to define the role of PORT in control after neck dissection and postoperative radiotherapy (PORT). Results: Overall, the RR rate after neck dissection and PORT was 29%. Extracapsular spread (ECS) was confirmed to be the only independent risk factor for RR. There were no significant risk factors associated with RR in the ECS- group. The 5-year disease-specific survival rate was 45%, which descended to 10% with the emergence of RR. Conclusions: ECS remains a determined risk factor for RR after neck dissection and PORT in patients with N+. PORT alone is not adequate for preventing RR in the neck with ECS after neck dissection. More intensive postoperative adjuvant therapies, especially combined chemotherapy and radiotherapy, are needed to prevent regional failure in HNSCC patients with ECS.

Trichodermamide A and Aspergillazine A, Two Cytotoxic Modified Dipeptides from a Marine-Derived Fungus Spicaria elegans

Liu Rui,Gu Qian-Qun,Zhu Wei-Ming,Cui Cheng-Bin,Fan Guo-Tao The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.9

Two known modified dipeptides, trichodermamide A (1) and aspergillazine A (2), were isolated from an ethyl acetate extract of the metabolite of a marine-derived fungus Spicaria elegans, and were found to have a weak cytotoxic effect on three cancer cell lines P388, A-549, and HL-60 agreed. To our knowledge, this is the first report on the isolation of compounds 1 and 2 from the fungus Spicaria elegans and their cytotoxic effect.