Fabrication of porous Si3N4 ceramics with controlled porosity by milling of fibrous α-Si3N4 powder Influence of zircon on cristobalite crystallization of

Zhaoyun Xu,Yaming Zhang,Bo Wang,Jian-feng Yang,Kaikai Liu 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.8

Porous Si3N4 ceramics with varied porosities were prepared by liquid phase sintering of fibrous α-Si3N4 powder with differentmorphology after ball milling. The influence of the ball milling time on porosity, shrinkage, microstructure and mechanicalproperties of Si3N4 ceramics were investigated. With increasing of the ball milling time from 0 h to 24 hrs, the mean length andaspect ratio of the fibrous α-Si3N4 particles decreased dramatically, resulting in the porosity of porous Si3N4 ceramics decreasedfrom 55.6% to 19.3%. With the decreased length of the fibrous α-Si3N4 particles, microstructures with decreased aspect ratioof β-Si3N4 grains were formed, as a result of increased nuclei number and limited grain growth of the β-Si3N4 grains. Theflexural strength varied from 62 MPa to 205 MPa could be obtained attributed to the synergy effect of porosity andmicrostructure.

Efficient Parallel TLD on CPU-GPU Platform for Real-Time Tracking

( Zhaoyun Chen ),( Dafei Huang ),( Lei Luo ),( Mei Wen ),( Chunyuan Zhang ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.1

Trackers, especially long-term (LT) trackers, now have a more complex structure and more intensive computation for nowadays’ endless pursuit of high accuracy and robustness. However, computing efficiency of LT trackers cannot meet the real-time requirement in various real application scenarios. Considering heterogeneous CPU-GPU platforms have been more popular than ever, it is a challenge to exploit the computing capacity of heterogeneous platform to improve the efficiency of LT trackers for real-time requirement. This paper focuses on TLD, which is the first LT tracking framework, and proposes an efficient parallel implementation based on OpenCL. In this paper, we firstly make an analysis of the TLD tracker and then optimize the computing intensive kernels, including Fern Feature Extraction, Fern Classification, NCC Calculation, Overlaps Calculation, Positive and Negative Samples Extraction. Experimental results demonstrate that our efficient parallel TLD tracker outperforms the original TLD, achieving the 3.92 speedup on CPU and GPU. Moreover, the parallel TLD tracker can run 52.9 frames per second and meet the real-time requirement.

Study of physical simulation of electrochemical modification of clayey rock

Chai, Zhaoyun,Zhang, Yatiao,Scheuermann, Alexander Techno-Press 2016 Geomechanics & engineering Vol.11 No.2

Clayey rock has large clay mineral content. When in contact with water, this expands considerably and may present a significant hazard to the stability of the rock in geotechnical engineering applications. This is particularly important in the present work, which focused on mitigating some unwelcomed properties of clayey rock. Changes in its physical properties were simulated by subjecting the rock to a low voltage direct current (DC) using copper, steel and aluminum electrodes. The modified mechanism of the coupled electrical and chemical fields acting on the clayey rock was analyzed. It was concluded that the essence of clayey rock electrochemical modification is the electrokinetic effect of the DC field, together with the coupled hydraulic and electrical potential gradients in fine-grained clayey rock, including ion migration, electrophoresis and electro-osmosis. The aluminum cathodes were corroded and generated gibbsite at the anode; the steel and copper cathodes showed no obvious change. The electrical resistivity and uniaxial compressive strength (UCS) of the modified specimens from the anode, intermediate and cathode zones tended to decrease. Samples taken from these zones showed a positive correlation between electric resistivity and UCS.

Precision Therapy in Acromegaly: How Close Is It to Reality?

구철룡,Vladimir Melnikov,Zhaoyun Zhang,이은직 대한내분비학회 2020 Endocrinology and metabolism Vol.35 No.2

Acromegaly presents with an enigmatic range of symptoms and comorbidities caused by chronic and progressive growth hormoneelevations, commonly due to endocrinologic hypersecretion from a pituitary gland tumor. Comprehensive national acromegaly databases have been appearing over the years, allowing for international comparisons of data, although still presenting varying prevalence and incidence rates. Lack of large-scale analysis in geographical and ethnic differences in clinical presentation and management requires further research. Assessment of current and novel predictors of responsiveness to distinct therapy can lead to multilevel categorization of patients, allowing integration into new clinical guidelines and reduction of increased morbidity and mortality associated with acromegaly. This review compares current data from epidemiological studies and assesses the present-day applicationof prognostic factors in medical practice, the reality of precision therapy, as well as its future prospects in acromegaly, with a specialfocus on its relevance to the South Korean population.

A positive feedback loop of heparanase/ syndecan1/nerve growth factor regulates cancer pain progression

Xiaohu Su,Bingwu Wang,Zhaoyun Zhou,Zixian Li,Song Tong,Simin Chen,Nan Zhang,Su Liu,Maoyin Zhang 대한통증학회 2023 The Korean Journal of Pain Vol.36 No.1

Background: The purpose of this research was to assess the role of heparanase (HPSE)/syndecan1 (SDC1)/nerve growth factor (NGF) on cancer pain from melanoma. Methods: The influence of HPSE on the biological function of melanoma cells and cancer pain in a mouse model was evaluated. Immunohistochemical staining was used to analyze HPSE and SDC1. HPSE, NGF, and SDC1 were detected using western blot. Inflammatory factors were detected using ELISA assay. Results: HPSE promoted melanoma cell viability, proliferation, migration, invasion, and tumor growth, as well as cancer pain, while SST0001 treatment reversed the promoting effect of HPSE. HPSE up-regulated NGF, and NGF feedback promoted HPSE. High expression of NGF reversed the inhibitory effect of HPSE down-regulation on melanoma cell phenotype deterioration, including cell viability, proliferation, migration, and invasion. SST0001 down-regulated SDC1 expression. SDC1 reversed the inhibitory effect of SST0001 on cancer pain. Conclusions: The results showed that HPSE promoted melanoma development and cancer pain by interacting with NGF/SDC1. It provides new insights to better understand the role of HPSE in melanoma and also provides a new direction for cancer pain treatment.

Research on Realization of Integrated Output Current Sharing Control by Moving Average Filter for Synchronous Generator

Liu Jinfeng,Xu Zhaoyun,Zhang Zhenglei,Iu Herbert Ho-Ching 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.1

The low voltage, high current rectifer module is the core of the integrated DC output system based on synchronous generators. In addition, modular control improves the fexibility of the system control and fault-tolerant operation ability. Due to the dispersion of the on-state voltage drop of switching devices, it is possible to cause a circulating current fault between the parallel modules, which leads to the reduction of the current sharing characteristics and stability of the system. Therefore, it is signifcant to address the shortcomings of traditional current sharing methods such as poor anti-disturbance performance. This paper proposes a current sharing scheme that improves the control accuracy by fltering the sampled current on the basis of autonomous sharing of maximum current. Furthermore, a model of the integrated generator rectifer system was established by Simulink to realize the simulation of the modular SVPWM (Space-Vector Pulse-Width Modulation) rectifer control based on MA (Moving Average) fltering algorithm. At last, an experimental platform was built in this paper in order to verify the feasibility of the theory. In this experimental platform, the controller completes digital current sharing control and fnally realizes the synchronous generator module paralleling system 5 V/1000A DC output. The simulation and experiment demonstrate that the integrated output current sharing control method in this paper has higher control precision and better anti-interference performance.

Lineage conversion of mouse fibroblasts to pancreatic α-cells

Lijian Hui,Liangliang Sun,Beige Jiang,Limei Li,Jin Cen,Xiaotao Chen,Zhaoyun Zhang,Qinghua Wang,Xin Cheng,Yongquan Shi,Lijian Hui 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

α-cells, which synthesize glucagon, also support β-cell survival and have the capacity to transdifferentiate into β-cells. However, the role of α-cells in pathological conditions and their putative clinical applications remain elusive due in large part to the lack of mature α-cells. Here, we present a new technique to generate functional α-like cells. α-like cells (iAlpha cells) were generated from mouse fibroblasts by transduction of transcription factors, including Hhex, Foxa3, Gata4, Pdx1 and Pax4, which induce α-cell-specific gene expression and glucagon secretion in response to KCl and Arg stimulation. The cell functions in vivo and in vitro were evaluated. Lineage-specific and functional-related gene expression was tested by realtime PCR, insulin tolerance test (ITT), glucose tolerance test (GTT), Ki67 and glucagon immunohistochemistry analysis were done in iAlpha cells transplanted nude mice. iAlpha cells possess α-cell function in vitro and alter blood glucose levels in vivo. Transplantation of iAlpha cells into nude mice resulted in insulin resistance and increased β-cell proliferation. Taken together, we present a novel strategy to generate functional α-like cells for the purposes of disease modeling and regenerative medicine.

Effect of Restricted Grazing Time on the Foraging Behavior and Movement of Tan Sheep Grazed on Desert Steppe

Chen, Yong,Luo, Hailing,Liu, Xueliang,Wang, Zhenzhen,Zhang, Yuwei,Liu, Kun,Jiao, Lijuan,Chang, Yanfei,Zuo, Zhaoyun Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.5

To investigate the effect of restricted grazing time on behavior of Tan sheep on desert steppe, forty 4-months old male Tan sheep with an original body weight (BW) of $15.62{\pm}0.33$ kg were randomly allocated to 4 grazing groups which corresponded to 4 different restricted grazing time treatments of 2 h/d (G2), 4 h/d (G4), 8 h/d (G8) and 12 h/d (G12) access to pasture. The restricted grazing times had a significant impact on intake time, resting time, ruminating time, bite rate and movement. As the grazing time decreased, the proportion of time spent on intake, bite rate and grazing velocity significantly (p<0.05) increased, but resting and ruminating time clearly (p<0.05) decreased. The grazing months mainly depicted effect on intake time and grazing velocity. In conclusion, by varying their foraging behavior, Tan sheep could improve grazing efficiency to adapt well to the time-limited grazing circumstance.