The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens

Feng Wang,Xiaowei Wang,Hongbo Chen,Jianzhu Liu,Ziqiang Cheng 대한수의학회 2011 JOURNAL OF VETERINARY SCIENCE Vol.12 No.3

The critical time of avian leukosis virus subgroup J (ALV-J)-mediated immunosuppression was determined by body weight, relative immune organ weight, histopathology, and presence of group specific antigen and antibodies in specific pathogen-free (SPF) chickens. CD4^+ and CD8^+ cell activity in the spleen, total and differential leukocyte counts in blood, and viral RNA levels in spleen were measured. Significant growth suppression was observed in the two ALV-J-infected groups. A strong immune response by infected groups was present in spleen at 2-weeks-of-age, but after 4-weeks-of-age, the response decreased quickly. The thymus and bursa showed persistent immunosuppression until 4-weeks-of-age. Proliferation of fibroblasts and dendritic cells were observed in immune organs at 4- and 5-weeks-of-age. However, the granulocyte cell number was markedly lower in the infected groups than in the control group. In group 1 (day 1 infection) CD4^+ cells increased during the second week but significantly decreased during the fourth week, while group 2 (day 7 infection) showed the opposite effect. Viral RNA increased significantly by the fourth week. These data identify 3∼4 weeks post-infection as the key time at which the ALV-J virus exerts its immunosuppressive effects on the host.

A 2-40 Gb/s PAM4/NRZ Dual-mode Wireline Transmitter with 4:1 MUX in 65-nm CMOS

Fangxu Lv,Xuqiang Zheng,Feng Zhao,Jianye Wang,Ziqiang Wang,Shuai Yuan,Yajun He,Chun Zhang,Zhihua Wang 대한전자공학회 2018 Journal of semiconductor technology and science Vol.18 No.2

This paper presents a 2-40 Gb/s dual-mode wireline transmitter supporting the four-level pulse amplitude modulation (PAM4) and non-return-tozero (NRZ) modulation with a multiplexer (MUX)-based two-tap feed-forward equalizer (FFE). An edgeacceleration technique is proposed for the 4:1 MUX to increase the bandwidth. By utilizing a dedicated cascode current source, the output swing can achieve 900 mV with a level deviation of only 0.12% for PAM4. Fabricated in a 65-nm CMOS process, the transmitter consumes 117 mW and 89 mW at 40 Gb/s in PAM4 and NRZ at 1.2 V supply.

Sciatic nerve leachate of cattle causes neuronal differentiation of PC12 cells via ERK1/2 signaling pathway

Ziqiang Zhang,Yumei Liu,Xuemin Zhu,Lan Wei,Jiamin Zhu,Ke Shi,Guotao Wang,Li Pan 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.4

Previous studies have shown that the sciatic nerve has neurotrophic activity, and nerve regeneration, differentiation, and axon outgrowth can be modulated by different sciatic nerve preparations. However, numerous animals may have to be sacrificed to obtain enough sciatic nerves to make a sciatic nerve preparation. Some studies have demonstrated that the role of sciatic nerve preparations in neural differentiation depends on the neurotrophins that Schwann cells secrete, and these factors are highly conserved among different species. To reduce the use of experimental animals, in this study, we made a leachate by using the sciatic nerve of cattle and explored its effect on neuronal differentiation of rat PC12 cells (a useful model for studying neuronal differentiation). Results showed the neurite outgrowth of PC12 cells treated with the cattle sciatic nerve leachate for 3, 6, and 9 days was significantly improved, and the expressions of β3-tubulin and microtubule-associated protein 2 (two neuron-specific proteins) were increased. Moreover, the ERK1/2 signaling pathway was activated after PC12 cells were incubated with cattle sciatic nerve leachate for 9 days. Thus, a sciatic nerve leachate obtained from cattle can effectively induce neuronal differentiation of rat PC12 cells via ERK1/2 signaling pathway.

Effects of Different Atmosphere on Electrochemical Performance of Hard Carbon Electrode in Sodium Ion Battery

Ziqiang Xu,Jinchen Chen,Mengqiang Wu,Cheng Chen,Yaochen Song,Yuesheng Wang 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.4

Hard carbon is deemed to be a most promising anode materials for sodium—ion batteries (SIBs), while, the issues of lowcapacity and low initial coulombic efficiency still exist limiting the development of SIBs. Although high temperature carbonizationof biomass materials under nitrogen or argon atmosphere is a common method for preparation of hard carbon,there are few reports about the effects of different protective atmospheres on propriety of hard carbon. In this article, hornet’snest (HN) is used to prepare hard carbon under nitrogen and argon. At a suitable carbonization temperature (1200 °C and1400 °C), the hard carbon under argon possesses lower specific surface area (25–50 cm−3 g−1), but higher initial coulombefficiency (4–6%) and higher capacity retention (3–6%). Thus, it is inferred that high—performance hard carbon can beobtained under argon atmosphere. Our research about the effect of sintering atmosphere on material properties is expectedto provide a reference for the synthetization of hard carbon by high temperature carbonization.

Applications of Heavy Ion Irradiation in Photonic Crystal Research

Ziqiang Zhao,Yingmin Liu,Yan Chen,Ding Lan,Yuren Wang 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle’s shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 × 1014 cm−2 to 1 × 1015 cm−2, respectively. Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle’s shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 × 1014 cm−2 to 1 × 1015 cm−2, respectively.

Rigid-flexible coupling dynamic modeling and performance analysis of a bioinspired jumping robot with a six-bar leg mechanism

Ziqiang Zhang,Lun Wang,Jinnong Liao,Jing Zhao,Qi Yang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8

The rigid-flexible coupling structure of creatures with jumping ability has the advantages of high stiffness and good flexibility, which are of great significance to its research. However, existing research on jumping robots has not demonstrated the effect of multiflexibility links on the jumping performance. In this paper, a Watt-type one degree-of-freedom six-bar mechanism is regarded as research object. For a jumping leg including multiple flexible links and a flexible joint with a floating frame, a rigid-flexible coupling dynamic model is established with a pseudo-rigid-body model being used. On this basis, the effect of structural and installation parameters on the jumping performance is analyzed. Results show that different flexible links have distinct effects on the jumping performance, and properly reducing the stiffness of flexible links can improve the jumping performance. The results of this study provide a design basis for jumping robots with a rigid-flexible coupling structure.

Effect of the raceway defects on the nonlinear dynamic behavior of rolling bearing

Ziqiang Zhao,Xuebin Yin,Wenzhong Wang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.6

The defects on raceways would aggravate the vibration of bearing and greatly influence the bearing performance, in order to monitor the running state of the bearing and detect the early defect, the characteristics induced by the defect must be explored. This paper establishes a bearing dynamic model to explore the effect of raceway defects on the nonlinear dynamic behavior of rolling element bearing. The interaction between ball and races is modeled based on Hertz theory, while the presence of defects changes the ball-race interaction. The effects of defect size, position and number on bearing dynamic behaviors are investigated with the aid of phase trajectories, shaft center orbits, FFT spectra, etc. The results indicate that the defects can make the motion of the system more complicated and induce vibration at some characteristic frequencies, which can be used to recognize the bearing failure at early stage. The proposed research provides useful information for the design and status monitoring of mechanical systems.

Environmental Friendly Intumescent Flame Retardant Gives Epoxy Resin Excellent Fire Resistance and Mechanical Properties

Huan Wang,Li Li,Yan Kang,Xue Yin,Xuedi Lei,Jing Yang,Hui Xi,Xueqing Xu,Zhiwang Yang,Ziqiang Lei 한국고분자학회 2022 Macromolecular Research Vol.30 No.8

To reduce the fire hazard of epoxy resin (EP), PA-CS-M (where PA = phytic acid, CS =c hitosan, M=Cu2+, Co2+, Al3+, Zn2+, Mn2+) environmental friendly flame retardant is prepared by a simple and green method. By comparing the data after cone calorimetry test (CCT) of various composites, it is found that when 5 wt% PA-CS-Mn is added to EP, it has good flame retardant and smoke suppression performance. The peak heat release rate (pk-HRR) decreased by 38% and the smoke production rate (SPR) decreased by 33%. In addition, some toxic smoke such as CO has been significantly inhibited. The structures and morphologies of the materials were investigated by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). When combined with expandable graphite (EG), it is found that when the ratio of PA-CS-Mn to EG is 1:5, the pk-HRR value and SPR value decreased by 69.8% and 66.6%, respectively. More importantly, the mechanical properties of the EP composites have also been greatly improved. The flexural modulus reaches 5.04 GPa, which is 52.3% higher than pure EP, and the flexural strength increases to 79.4 MPa, which also shows an increase of 41.4% as to the matrix.

Eco-Friendly Electrochemical Biosensor based on Sodium Carboxymethyl Cellulose/Reduced Graphene Oxide Composite

Meng Cui,Ziqiang Shao,DAYONG LU,Yang Wang 한국고분자학회 2019 Macromolecular Research Vol.27 No.4

Reduced graphene oxide (GO) and carboxymethyl cellulose sodium (CMC) composite film was prepared by a simple solution blending method. The obtained composite film was used to modify glassy carbon electrode (GCE) to detect Vitamin B6 (VB6) with electrochemical measurements. Morphologies and stucture of the composite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR). The electrochemistry performances of the GCE modified by GO/CMC composite were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The results revealed that CMC and GO were able to form a homogeneous mixture, and the modified GCE presented extremely strong sensitivity towards VB6 such as high detection sensitivity, low detection limit, small Ret value, certain stability and excellent reversibility. The good performance might be attributed to high electrical conductivity and large surface-to-volume ratio of GO which could accelerate electron transfer between the surface of GCE and VB6. The test results showed that GO/CMC composite was a novel electrochemical biosensor for the detection of VB6.

Experimental Study of Seismic Damage with Park-Ang Model for Recycled Aggregate Concrete Columns

Yujiang Fan,Ziqiang Guo,Yachao Wang,Pengcheng Zhao,Binshan Yu 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.9

By means of the low cycle loading tests on six recycled aggregate concrete (RAC) columns with different proportions, in combination with the Park-Ang two-parameter damage model suitable for ordinary concrete columns and the damage degree Dc of actual structures, the calculated value of cyclic loading coefficient β of recycled aggregate concrete columns was determined. It would be achieved by analyzing the calculated β that the impact of the replacement ratio of recycled aggregate and the content of mixed fibers on β was significantly different. Considering the reinforcement ratio mentioned in paper. Matlab was further employed to fit multivariable linear equation regarding recycled aggregate replacement ratio, mixed fibers contents and reinforcement rate as the basis, so that the computation formula of the cyclic loading coefficient β suitable for recycled aggregate concrete columns was revealed.