Evaluation of Electrospinnability of Celluloses Derived from Different Biomass Resources

Yanhua Chen,Na Teng,Haizhen Chen,Jing Chen,Fei Liu,Haining Na,Jin Zhu 한국섬유공학회 2018 Fibers and polymers Vol.19 No.5

Electrospinnability as well as dissolvability of the celluloses derived from different biomass resources are systematically studied in this work. By analyzing the essentially physical and molecular structure of cellulose in detail, dissolving efficiency and molecular chain entanglement in solution of cellulose are carefully realized. Accordingly, the original factors on electrospinnability of cellulose is revealed. Crystallinity mainly affects the dissolution of cellulose, which is the foundation to achieve electrospinning. Degree of polymerization is the decisive index of cellulose to form molecular entanglement in solution or not. Proper molecular entanglement of cellulose, just as corn cellulose II, could initiate the formation of ultrafine fiber with good morphology in electrospinning. Our research is no doubt helpful to establish a solid scientific and technical foundation for selection of cellulose to achieve high efficiency fabrication of ultrafine fiber in electrospinning.

Human Behavior Recognition Method based on Image Sequences

Yanhua Chen 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.2

Most researches on human behavior recognition are mainly based on the features of whole body motion. This paper proposed a hierarchical discriminative approach for recognizing human behavior based on limbs motion. The approach consists of feature extraction with mutual motion pattern analysis and discriminative behavior modeling in the hierarchical manifold space. A cascade CRF is introduced to estimate the motion patterns in the corresponding manifold subspace, and the trained SVM classifier is used to predict the behavior label for the current observation. The results on motion capure data prove the significance motion analysis of body parts, and the results on synthetic image sequences are also presented to demonstrate the robustness of the proposed algorithm.

Multicast Routing Algorithm Based On Genetic Algorithm

Yanhua Chen 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.6

MRAGA (Multicast Routing Algorithm based on Genetic algorithm) for the Delay-Constrained Minimum-Energy Multicast Routing problem was presented. The genetic operators of this algorithm reduce the transmission delay and energy consumption of multicast trees, thus accelerating the convergence speed of the algorithm. Experiment results show that the multicast tree found by this algorithm not only guarantee the delay constraint, but also has the minimum energy consumption. Furthermore, this algorithm converges quickly.

Dynamic behavior of SRC columns with built-in cross-shaped steels subjected to lateral impact

Yanhua Liu,Lei Zeng,Changjun Liu,Jinxu Mo,Buqing Chen 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.4

This paper presents an investigation on the dynamic behavior of SRC columns with built-in cross-shaped steels under impact load. Seven 1/2 scaled SRC specimens were subjected to low-speed impact by a gravity drop hammer test system. Three main parameters, including the lateral impact height, the axial compression ratios and the stirrup spacing, were considered in the response analysis of the specimens. The failure mode, deformation, the absorbed energy of columns, as well as impact loads are discussed. The results are mainly characterized by bending-shear failure, meanwhile specimens can maintain an acceptable integrity. More than 33% of the input impact energy is dissipated, which demonstrates its excellent impact resistance. As the impact height increases, the flexural cracks and shear cracks observed on the surface of specimens were denser and wider. The recorded time-history of impact force and mid-span displacement confirmed the three stages of relative movement between the hammer and the column. Additionally, the displacements had a notable delay compared to the rapid changes observed in the measured impact load. The deflection of the mid-span did not exceed 5.90mm while the impact load reached peak value. The impact resistance of the specimen can be improved by proper design for stirrup ratios and increasing the axial load. However, the cracking and spalling of the concrete cover at the impact point was obvious with the increasing in stiffness.

SHAPE OPTIMIZATION OF THIN-WALLED CROSS SECTION FOR AUTOMOBILE BODY CONSIDERING STAMPING COST, MANUFACTURABILITY AND STRUCTURAL STIFFNESS

Yanhua Ma,Rui Chen,Jiantao Bai,Wenjie Zuo 한국자동차공학회 2020 International journal of automotive technology Vol.21 No.2

At the conceptual design stage, the cross-sectional shapes of thin-walled beams (TWBs) need to be optimized to improve the performance of automobile structure. Therefore, this paper innovatively proposes a cross-sectional shape optimization method to acquire a low cost, high stiffness, manufacturable and lightweight TWB. Meanwhile, the stamping cost of thin-walled beams is analytically derived. The cross-sectional area is taken as the objective function to establish an optimization formulation with multiple constraints such as cross-sectional stiffness, manufacturability and cost of TWBs. The single-objective genetic algorithm based on non-dominant principle is introduced to solve the problem. The effectiveness of the proposed method is verified by an example of double cell cross-sectional shape.

One-Pot Synthesis of α-Fe2O3 Nanospindles as High-Performance Lithium-Ion Battery Anodes

Yanhua Ding,Bing Liu,Rongsheng Cai,Tuo Xin,Chen Li,Linhua Xia,Yiqian Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.2

Hematite nanospindles with a uniform size of ~270 nm in length and ~90 nm in width are prepared using a facile one-step hydrothermal method. Polyvinylpyrrolidone (PVP) serves as a structure-directing agent to control the primary morphology and aggregations. When evaluated as anode materials for lithium-ion batteries (LIBs), the electrode of sodium alginate (SA) binder exhibits a much better electrochemical performance than that with the polyvinylidene fluoride (PVDF) binder. Remarkably, the electrode using SA binder can deliver a high reversible specific capacity of 979mAh · g -1 after 50 cycles and prominent rate capability. The microstructural evolution of the nanospindles after the electrochemical cycling is investigated by scanning transmission electron microscopy (STEM). Our results may provide important mechanistic insights for the design of nanostructured anode materials for LIBs.

NINJ1 triggers extravillous trophoblast cell dysfunction through blocking the STAT3 signaling pathway

Zhang Xueluo,Chen Yanhua,Wang Xianping,Zhang Zhiping,Wang Jun,Shen Yan,Hu Yuanjing,Wu Xueqing 한국유전학회 2022 Genes & Genomics Vol.44 No.11

Background: Trophoblasts are the most important parts of the placenta in early pregnancy. Trophoblast cell dysfunction can induce embryo implantation insufficiency, thereby resulting in multiple diseases, including recurrent spontaneous abortion (RSA). A previous study indicates higher nerve injury-induced protein 1 (NINJ1) RNA levels in the villi tissues of RSA patients. Objective: This study aimed to investigate the effect of NINJ1 on trophoblast behaviors and pregnancy loss. Methods: Fresh villi tissues were obtained from with RSA patients and patients with artificial selective abortion for personal reasons, and NINJ1 expression in these tissues was detected. Extravillous trophoblast cell line HTR-8/SVneo was transfected with small-interfering RNA targeting NINJ1 or NINJ1 overexpression vector to perform loss-/gain-of-function experiments. Spontaneous abortion (SA) was induced by mating CBA/J females with DBA/2 males and the pregnant females were intraperitoneally injected with adenovirus vector carrying NINJ1 short hairpin RNA. Results: NINJ1 mRNA and protein levels were higher in the villi tissues of RSA patients than those of artificial selective abortion patients. NINJ1 knockdown promoted trophoblast cell proliferation, migration and invasion but inhibited cell apoptosis. Moreover, conditioned medium from NINJ1-depleted trophoblasts promoted the angiogenesis of human umbilical vein endothelial cells. NINJ1 knockdown also promoted activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway in trophoblasts, and STAT3 inhibitor reversed NINJ1 knockdown-induced effects on trophoblast behaviors. Furthermore, pregnancy loss was attenuated by NINJ1 inhibition. Conclusion: NINJ1 contributes to the development of SA and triggers trophoblast cell dysfunction through inhibiting the STAT3 pathway.

Arching Effect between the Pipes of a Pipe Umbrella Support Systemin a Shallow-Buried Tunnel

Chao Yang,Yanhua Chen,Da Huang,Lehua Wang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.12

The pipe umbrella is one of the most commonly used prereinforcement techniques in tunnel construction. Current theoretical analyses of the pipe umbrella support mechanism are primarily based on the elastic foundation beam principle, whereby only a single pipe is concerned, and the interactions among pipes are ignored. In this study, a double-parameter elastic foundation beam theory-based model was established with consideration of the arching effect between two pipes. The model can simulate the support mechanism of the pipe umbrella system in shallow-buried tunnels. The support mechanisms of a pipe umbrella system installed in a rectangular tunnel and an arched tunnel were investigated. In the two cases, the arching effect and a single pipe were considered. The results indicate that the arching effect leads to larger pipe deflection and internal forces than considering a single pipe. The influences of the diameter of a single pipe, the distance between two pipes and the shear parameters of the surrounding rock on the pipe deflection and the arching effect are discussed. In addition, the proposed model was validated by the in situ monitoring results.

LasR Might Act as an Intermediate in Overproduction of Phenazines in the Absence of RpoS in Pseudomonas aeruginosa

( Qiuning He ),( Zhibin Feng ),( Yanhua Wang ),( Kewen Wang ),( Kailu Zhang ),( Le Kai ),( Xiuying Hao ),( Zhifen Yu ),( Lijuan Chen ),( Yihe Ge ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.8

As an opportunistic bacterial pathogen, Pseudomonas aeruginosa PAO1 contains two phenazineproducing gene operons, phzA1B1C1D1E1F1G1 (phz1) and phzA2B2C2D2E2F2G2 (phz2), each of which is independently capable of encoding all enzymes for biosynthesizing phenazines, including phenazine-1-carboxylic acid and its derivatives. Other previous study reported that the RpoS-deficient mutant SS24 overproduced pyocyanin, a derivative of phenazine-1- carboxylic acid. However, it is not known how RpoS mediates the expression of two phz operons and regulates pyocyanin biosynthesis in detail. In this study, with deletion of the rpoS gene in the PAΔphz1 mutant and the PAΔphz2 mutant respectively, we demonstrated that RpoS exerted opposite regulatory roles on the expression of the phz1and phz2 operons. We also confirmed that the phz1 operon played a critical role and especially biosynthesized much more phenazines than the phz2 operon when the rpoS gene was knocked out in P. aeruginosa. By constructing the translational reporter fusion vector lasR’-’lacZ and the chromosomal fusion mutant PAΔlasR::lacZ, we verified that RpoS deficiency caused increased expression of lasR, a transcription regulator gene in a first quorum sensing system (las) that activates overexpression of the phz1 operon, suggesting that in the absence of RpoS, LasR might act as an intermediate in overproduction of phenazine biosynthesis mediated by the phz1 operon in P. aeruginosa.

Bmo-miR-3377-5p down-regulates the Bombyx mori Sericin gene-1

Kandhro Rehana,Tao Jianga,Yanhua Chen,Juan Zhu,Shunming Tang,Xingjia Shen 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

MiRNAs are small non-coding molecules, which can regulate a huge number of genes. Based on bioinformatics analysis, we found a target site in the 3′UTR of BmSer-1 for binding bmo-miR-3377-5p. By using semi-quantitative RT-PCR, we detected that miR-3377-5p and BmSer-1 were both more highly expressed in the middle silk gland than in other tissues of 3-day-old fifth-instar Bombyx mori larvae, implying that there is a spatiotemporal condition for miR-3377-5p regulating on BmSer-1. To confirm this prediction, a BmSer-13′UTR recombinant luciferase reporter pGL3.0 [A3-luc-BmSer-1-3′UTR-SV40] and pri-bmo-miR-3377-5p expression pcDNA3.0 [ie1-egfppri-bmo-miR-3377-5p-SV40] were constructed and co-transfected into B. mori ovary cells (BmN cells). The results showed that miR-3377-5p suppressed the expression of BmSer-1 significantly (P < .001). When BmN cells were co-transfected by an artificial inhibitor together with a miR-3377-5p expression vector and a BmSer-1-3′UTR recombinant plasmid, BmSer-1 expression increased significantly (P < .05), indicating that the inhibitor was active against miR-3377-5p, and expression of BmSer-1 was recovered. Moreover, we injected miR-3377-5p expression plasmid and bmo-miR-3377-5p inhibitor into 3-day-old fifth-instar larvae. At 36 h post-injection, silk glands were collected for total RNA extraction. Quantitative RT-PCR analysis showed that miR-3377-5p downregulated the expression of BmSer-1 in vivo, while there was no significant difference inhibitor treatment group compared with NC. Thus, we conclude that miR-3377-5p down-regulated the expression of BmSer-1. Our results provide insight for understanding the function of miRNAs and the regulation network of silk protein genes.