White-Matter Hyperintensities and Lacunar Infarcts Are Associated with an Increased Risk of Alzheimer’s Disease in the Elderly in China

Shuai Ye,Shuyang Dong,Jun Tan,Le Chen,Hai Yang,Yang Chen,Zeyan Peng,Yingchao Huo,Juan Liu,Mingshan Tang,Yafei Li,Huadong Zhou,Yong Tao 대한신경과학회 2019 Journal of Clinical Neurology Vol.15 No.1

Background and Purpose This study investigated the contribution of white-matter hyperintensities (WMH) and lacunar infarcts (LI) to the risk of Alzheimer’s disease (AD) in an elderly cohort in China. Methods Older adults who were initially cognitively normal were examined with MRI at baseline, and followed for 5 years. WMH were classified as mild, moderate, or severe, and LI were classified into a few LI (1 to 3) or many LI (≥4). Cognitive function was assessed using the Mini Mental State Examination and the Activities of Daily Living scale. Results Among the 2,626 subjects, 357 developed AD by the end of the 5-year follow-up period. After adjusting for age and other potential confounders, having only WMH, having only LI, and having both WMH and LI were associated with an increased risk of developing AD compared with having neither WMH nor LI. Moderate and severe WMH were associated with an increased risk of developing AD compared with no WMH. Furthermore, patients with many LI had an increased risk of developing AD compared with no LI. Conclusions Having moderate or severe WMH and many LI were associated with an increased risk of developing AD, with this being particularly striking when both WMH and LI were present.

Research on active flow control to reduce aerodynamic drag of mira notchback model

Yingchao Zhang,Ruizhuo Zhou,Jinji Li,Hui Zhu,Haipeng Liu,Zhe Zhang,Chengchun Zhang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.11

The lattice Boltzmann method, combined with the boundary layer model and the very large eddy simulation method, was used to simulate the MIRA notchback model to obtain an accurate unsteady flow field and a more reliable mean flow field. Based on the analysis of the tail flow state, jet holes were set up at the model tail. To analyze the effects of different jet states on the aerodynamic performance, constant jet method was used to explore the optimal values of blowing and sucking conditions, jet hole diameters and jet velocities at each position. The numerical results indicate that setting up the jet scheme can reduce the drag coefficient by inhibiting the longitudinal vortex and improving the wake structure of the model. A case of single jet placing jet holes at the bottom of the rear windshield can achieve 10 % drag reduction.

Fermentation characteristics, chemical composition and microbial community of tropical forage silage under different temperatures

Dongxia Li,Kuikui Ni,Yingchao Zhang,Yanli Lin,Fuyu Yang 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.5

Objective: In tropical regions, as in temperate regions where seasonality of forage production occurs, well-preserved forage is necessary for animal production during periods of forage shortage. However, the unique climate conditions (hot and humid) and forage characteristics (high moisture content and low soluble carbohydrate) in the tropics make forage preservation more difficult. The current study used natural ensiling of tropical forage as a model to evaluate silage characteristics under different temperatures (28°C and 40°C). Methods: Four tropical forages (king grass, paspalum, white popinac, and stylo) were ensiled under different temperatures (28°C and 40°C). After ensiling for 30 and 60 days, samples were collected to examine the fermentation quality, chemical composition and microbial community. Results: High concentrations of acetic acid (ranging from 7.8 to 38.5 g/kg dry matter [DM]) were detected in silages of king grass, paspalum and stylo with relatively low DM (ranging from 23.9% to 30.8% fresh material [FM]) content, acetic acid production was promoted with increased temperature and prolonged ensiling. Small concentrations of organic acid (ranging from 0.3 to 3.1 g/kg DM) were detected in silage of white popinac with high DM content (50.8% FM). The microbial diversity analysis indicated that Cyanobacteria originally dominated the bacterial community for these four tropical forages and was replaced by Lactobacillus and Enterobacter after ensiling. Conclusion: The results suggested that forage silages under tropical climate conditions showed enhanced acetate fermentation, while high DM materials showed limited fermentation. Lactobacillus and Enterobacter were the most probable genera responsible for tropical silage fermentation.

Insect cytokine growth-blocking peptide may regulate density-dependent phase trait of cuticular melanization in the larval armyworm, Mythimna separata

Zhang Yingchao,He Juan,Zhang Yuxia,Li Yue,Yu Yang,Jiang Xingfu,Pan Weidong 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

Growth-blocking peptide (GBP) is a 25 amino acid insect cytokine found in lepidopteran insects that has diverse biological activities such as larval growth regulation, paralysis induction, cell proliferation and stimulation of immune cells. Density-dependent phase polyphenism is a phenomenon of phenotypic plasticity in which the expression of a variety of traits can be affected by local population density. In the present study, the armyworm Mythimna separata larvae with four rearing densities (1 larva/vial, 2 larvae/vial, 4 larvae/vial and 6 larvae/vial) were tested for cuticular melanization and body weight throughout the third-fifth instar, and the functional role of GBP in regulating the changes was investigated. The results indicated that when reared at high densities, the larvae exhibited less body weight and more degree of cuticular melanization than larvae reared at low densities. The gene expression of GBP in armyworm larvae showed an initial rise and then decline trend with increased rearing densities in the third to fifth instar. Compared with control, more degree of cuticular melanization was observed in GBP-injected larvae (500 ng/larva in volume 50 μL) than that in Ringer’s solution-injected counterparts. Furthermore, the gene expression level of dopa decarboxylase and prophenoloxidase increased significantly in GBP-injected fifth instar larvae from 6 h to 12 h after injection, suggesting the role of GBP in modulating density-dependent phase trait of armyworm cuticular melanization.

A novel multistage approach for structural model updating based on sensitivity ranking

Yufeng Jiang,Yingchao Li,Shuqing Wang,Mingqiang Xu 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.25 No.6

A novel multistage approach is developed for structural model updating based on sensitivity ranking of the selected updating parameters. Modal energy-based sensitivities are formulated, and maximum-normalized indices are designed for sensitivity ranking. Based on the ranking strategy, a multistage approach is proposed, where these parameters to be corrected with similar sensitivity levels are updated simultaneously at the same stage, and the complete procedure continues sequentially at several stages, from large to small, according to the predefined levels of the updating parameters. At every single stage, a previously developed cross model cross mode (CMCM) method is used for structural model updating. The effectiveness and robustness of the multistage approach are investigated by implementing it on an offshore structure, and the performances are compared with nonmultistage approach using numerical and experimental vibration information. These results demonstrate that the multistage approach is more effective for structural model updating of offshore platform structures even with limited information and measured noise. These findings serve as a preliminary strategy for structural model updating of an offshore platform in service.

Ethylene increases accumulation of compatible solutes and decreases oxidative stress to improve plant tolerance to water stress in Arabidopsis

Mengying Cui,Yingchao Lin,YUANGANG ZU,Thomas Efferth,Dewen Li,Zhonghua Tang 한국식물학회 2015 Journal of Plant Biology Vol.58 No.3

Ethylene (ET) plays an important role as signal transducer in plants in response to environmental stimuli. Under water deficient conditions, fine adjustment of osmosis and redox states through phytohormones is vital for plant resistance to drought. Here, physiological and cellular responses of ET insensitive mutants (ein2-5 and ein3-1) were analyzed under water deficiency stimulated by polyethylene glycol 6000 (PEG-6000), and compared with wild type plants (Col-0) as controls. The accumulation of compatible solutes was higher in Col-0 than in ein2-5 and ein3-1. In Col-0 plants, water stress also increased transcription of P5CS1, which encoded a key rate-limiting enzyme in proline biosynthesis. These results suggested that ET signaling is involved in increasing the up-regulation of soluble sugar and proline accumulation to adjust to osmotic stress. In addition, oxidative stress was higher in ET defective mutants than in Col-0 wild-type plants. Meanwhile, increased activities of the reactive oxygen species (ROS)-scavenging enzymes superoxide dismutase (SOD) and peroxidase (POD) were observed in ET insensitive mutants, indicating aggravated oxidative stress in ET-defective plants under drought. In conclusion, ET signaling is involved in modulating plant oxidative stress under drought conditions.

Red Imported Fire Ant in China

Runzhi Zhang,Yingchao Li 한국응용곤충학회 2005 한국응용곤충학회 학술대회논문집 Vol.2005 No.05

Investigation on the Collapse Mechanism of Overlying Clay Layer Based on the Unified Strength Theory

Fan Chen,Yingchao Wang,Yuanhai Li,Wen Jiang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.9

Water and sand gushing will lead to the destruction of upper cohesive soil that further form cavity, and the ground collapse caused by the development of soil cavity adversely affects the geotechnical building or foundation. In this study, the theory of elastic mechanics clamped beam was used to establish the arbitrary point stress calculation model and the stress solution of the clay soil under the action of gravity was derived. According to the equilibrium state of ultimate stress and unified strength theory, the formula for calculating the critical radius of cavity induced by water and sand gushing was obtained. The parametric study of above formulas shows that the cavity radius decreases with the increased depth of clay layer and Poisson’s number of clay layer. The higher the clay cohesion is, the higher is the cavity clay. Moreover, the limit radius of cavity first increases and then decreases with the increased of clay thickness. The results of theoretical analysis of critical collapse radius and the results of model test demonstrate that the calculating value of critical collapse radius based on unified strength theory is consistent with the test results.

Investigation of aerodynamic behaviour of a high-speed train on different railway infrastructure scenarios under crosswind

Jiqiang Niu,Yingchao Zhang,Zheng-Wei Chen,Rui Li,Huadong Yao 한국풍공학회 2022 Wind and Structures, An International Journal (WAS Vol.35 No.6

The aerodynamic behaviour of a CRH high-speed train under three infrastructure scenarios (flat ground, embankment, and viaduct) in the presence of a crosswind was simulated using a 1/8th scaled train model with three cars and the IDDES framework. The time-averaged and instantaneous flow field around the model were examined. The employed numerical algorithm was verified through a wind tunnel test, and the grid and timestep resolution analyses were conducted to ensure the reliability of the data. It was noted that the flow around the rail line was different under different infrastructure scenarios, especially in the case of the embankment, which degraded the aerodynamic performance of the train under the crosswind. The flow around the train on the flat ground and viaduct was different, although the aerodynamic performance of the train was similar in both cases. Moreover, the viaduct accidents were noted to have the most critical consequences, thereby requiring the most attention. The aerodynamic performance of the train on the windward track of the embankment under the crosswind was worse than that of the train on the leeward track. But for the other two infrastructure scenarios, the aerodynamic performance of the train on the windward track is relatively dangerous, which is mainly caused by the head car. These observations suggest that the aerodynamic behaviour of the train on an embankment under a crosswind must be carefully considered and that certain wind protection measures must be adopted around rail lines in windy areas.

Direct Power Control of PWM Rectifier With Optimal Duty Ratio Under Unbalanced Network

Yongchang Zhang,Changqi Qu,Zhengxi Li,Yingchao Zhang,Longhan Cao 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Direct power control (DPC) attracted wide attention due to its advantages of simple structure, quick response, strong robustness and elimination of current regulation/PWM blocks. However, conventional table-based DPC cannot work well when grid voltage is unbalanced. This paper proposes an improved DPC by using a new definition of instantaneous reactive power. As a result, the distortion in grid current is eliminated and constant active power and new reactive power are obtained. Neither complicated calculation of power compensation nor positive/negative sequence extraction of grid voltage/current is required. The corresponding switching table suitable to regulate both active power and the new reactive power is established. Furthermore, the concept of duty cycle control is introduced to further improve the steady state performance of conventional DPC. Experimental results are presented to confirm the theoretical study and the effectiveness of the proposed method.