STUDY ON THE FRACTURE BEHAVIOR OF W-NI-FE HEAVY ALLOYS

WEIDONG SONG,JIANGUO NING,HAIYAN LIU 한국소성가공학회 2008 한국소성가공학회 컨퍼런스 Vol.2008 No.10

Overexpression of a Rice Diacylglycerol Kinase Gene OsBIDK1 Enhances Disease Resistance in Transgenic Tobacco

Weidong Zhang,Jie Chen,Huijuan Zhang,Fengming Song 한국분자세포생물학회 2008 Molecules and cells Vol.26 No.3

A rice diacylglycerol kinase (DGK) gene, OsBIDK1, which encodes a 499-amino acid protein, was cloned and characterized. OsBIDK1 contains a conserved DGK domain, consisting of a diacylglycerol kinase catalytic subdomain and a diacylglycerol kinase accessory subdomain. Expression of OsBIDK1 in rice seedlings was induced by treatment with benzothiadiazole (BTH), a chemical activator of the plant defense response, and by infection with Magnaporthe grisea, causal agent of blast disease. In BTH-treated rice seedlings, expression of OsBIDK1 was induced earlier and at a higher level than in water-treated control seedlings after inoculation with M. grisea. Transgenic tobacco plants that constitutively express the OsBIDK1 gene were generated and disease resistance assays showed that overexpression of OsBIDK1 in transgenic tobacco plants resulted in enhanced resistance against infection by tobacco mosaic virus and Phytophthora parasitica var. nicotianae. These results suggest that OsBIDK1 may play a role in disease resistance responses.

Evaluating CEOP Model Performance with the Observational Data from Tongyu Reference Site, Semi-arid Region of China

Yonghong Yao,Weidong Guo,Yaoming Song 한국기상학회 2010 Asia-Pacific Journal of Atmospheric Sciences Vol.46 No.3

Using data archived in the Coordinated Enhanced Observing Period (CEOP) project, comparisons between field observations undertaken at Tongyu CEOP reference site in China and model output from year 2003 to 2004 have been implemented, and in particular, the time series and diurnal cycles of precipitation, nearsurface temperature, air temperature, and latent and sensible heat fluxes are presented. The results show that the ability of the model simulations on the temperatures, such as air temperature and the surface temperature, is satisfactory compared with the simulations on the land surface heat fluxes and the precipitation at Tongyu site. In addition, the multi-model ensemble exhibits better results over all items in comparison with the observations. The differences of the precipitation at the interannual and the seasonal time scales between the model results and observations indicate that some of the models are able to reproduce the larger amount of precipitation in 2003 than that in 2004, which is consistent with the trend of the observations at Tongyu site even though the mean square errors of models output calculated from daily precipitation during year 2003 and 2004 are even greater than the daily amount of the precipitation. The poor skill in the quantitative simulation of the precipitation indicates that the deficiency of the models in simulating the surface heat fluxes may be closely related to the biases of the precipitation simulations. In terms of the seasonal time series of the precipitation, there is an increase during summer, accompanied by the same increased trend of the latent heat flux and the decreased trend of the sensible heat flux from the insitu observations.

Effect of FTY-720 on Pulmonary Fibrosis in Mice via the TGF-β1 Signaling Pathway and Autophagy

Jin Yuying,Liu Weidong,Gao Ge,Song Yilan,Liu Hanye,Li Liangchang,Zhou Jiaxu,Yan Guanghai,Cui Hong 한국응용약물학회 2023 Biomolecules & Therapeutics(구 응용약물학회지) Vol.31 No.4

We investigated whether FTY-720 might have an effect on bleomycin-induced pulmonary fibrosis through inhibiting TGF-β1 pathway, and up-regulating autophagy. The pulmonary fibrosis was induced by bleomycin. FTY-720 (1 mg/kg) drug was intraperitoneally injected into mice. Histological changes and inflammatory factors were observed, and EMT and autophagy protein markers were studied by immunohistochemistry and immunofluorescence. The effects of bleomycin on MLE-12 cells were detected by MTT assay and flow cytometry, and the related molecular mechanisms were studied by Western Blot. FTY-720 considerably attenuated bleomycin-induced disorganization of alveolar tissue, extracellular collagen deposition, and α-SMA and E-cadherin levels in mice. The levels of IL-1β, TNF-α, and IL-6 cytokines were attenuated in bronchoalveolar lavage fluid, as well as protein content and leukocyte count. COL1A1 and MMP9 protein expressions in lung tissue were significantly reduced. Additionally, FTY- 720 treatment effectively inhibited the expressions of key proteins in TGF-β1/TAK1/P38MAPK pathway and regulated autophagy proteins. Similar results were additionally found in cellular assays with mouse alveolar epithelial cells. Our study provides proof for a new mechanism for FTY-720 to suppress pulmonary fibrosis. FTY-720 is also a target for treating pulmonary fibrosis.

Sharpened VO₂ Phase Transition via Controlled Release of Epitaxial Strain

Lee, Daesu,Lee, Jaeseong,Song, Kyung,Xue, Fei,Choi, Si-Young,Ma, Yanjun,Podkaminer, Jacob,Liu, Dong,Liu, Shih-Chia,Chung, Bongwook,Fan, Wenjuan,Cho, Sang June,Zhou, Weidong,Lee, Jaichan,Chen, Long-Qin American Chemical Society 2017 NANO LETTERS Vol.17 No.9

<P>Phase transitions in correlated materials can be manipulated at the nanoscale to yield emergent functional properties, promising new paradigms for nanoelectronics and nanophotonics. Vanadium dioxide (VO2), an archetypal correlated material, exhibits a metal insulator transition (MIT) above room temperature. At the thicknesses required for heterostructure applications, such as an optical modulator discussed here, the strain state of VO2 largely determines the MIT dynamics critical to the device performance. We develop an approach to control the MIT dynamics in epitaxial VO2 films by employing an intermediate template layer with large lattice mismatch to relieve the interfacial lattice constraints, contrary to conventional thin film epitaxy that favors lattice match between the substrate and the growing film. A combination of phase-field simulation, in situ real-time nanoscale imaging, and electrical measurements reveals robust undisturbed MIT dynamics even at preexisting structural domain boundaries and significantly sharpened MIT in the templated VO2 films. Utilizing the sharp MIT, we demonstrate a fast, electrically switchable optical waveguide. This study offers unconventional design principles for heteroepitaxial correlated materials, as well as novel insight into their nanoscale phase transitions.</P>

Experimental study on unloading failure characteristics and damage evolution rules of deep diorite based on triaxial acoustic emission tests

Yang Li,Jianxin Fu,Nai Hao,Weidong Song,Ling Yu 한국지질과학협의회 2023 Geosciences Journal Vol.27 No.5

With the increasing depletion of shallow-earth mineral resources, deep mining will become the primary route of future mineral resources development. However, deep mining technology is a long way from being mature, and there are still a great number of issues that severely limit the growth of resources. In this paper, the acoustic emission (AE) tests of triaxially loaded and unloaded deep diorite are conducted. The results show that when confining pressure is at a low level, the failure mode of rock sample is mainly tension fracture; however as confining pressure increases, the failure mode gradually changes to shear failure. Under different stress paths, AE counting characteristics can be separated into four stages, including initial low-energy zone, pre-peak quiet zone, peak sudden burst zone and post-peak failure intensive zone (post-peak fast attenuation zone or post-peak high density zone). The damage variable is defined as the ratio of the AE count rate of a certain stage to the cumulative AE count rate of the failure process, and it accounts for the largest proportion at the stage of unloading confining pressure. In addition, when confining pressure increases, thedamage variable changes from a flat growth to a rapid growth, with the abrupt transition occurring around the peak stress.

Obesity parameters in relation to lung function levels in a large Chinese rural adult population

Zeng Xiang,Liu Dongling,An Zhen,Li Huijun,Song Jie,Wu Weidong 한국역학회 2021 Epidemiology and Health Vol.43 No.-

OBJECTIVES: The association between obesity parameters and lung function indicators in the general Chinese rural adult population remains unclear. METHODS: In total, 8,284 Chinese adults aged 20 years to 80 years old from Xinxiang were recruited. Obesity-related parameters, including body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waistto-height ratio (WHtR), body fat percentage (BFP), basal metabolism, and visceral fat index, and lung function parameters such as forced vital capacity and forced expiratory volume in first second were measured. RESULTS: The total prevalence of obesity defined by BMI, WC, WHR, WHtR, and BFP was 23.2%, 58.2%, 66.7%, 69.2%, and 56.5%, respectively. Spearman correlation analyses showed significant correlations between all obesity-related parameters and lung function. Linear regression analyses further demonstrated that BMI, WHtR, BFP, and general obesity defined using those indicators were negatively associated with lung function, while WC, WHR, and central obesity defined accordingly were positively associated with lung function. The relationship between general obesity and lung function was more evident in women than in men, while the link between central obesity and lung function was more obvious in men than in women. CONCLUSIONS: Obesity is closely related to lung function in the general Chinese adult population. Weight control and loss are important strategies to improve lung function and respiratory health.

Substrate effect on phonon in graphene layers

Xiao Guo,Yongsong Wang,Siwen You,Dingbang Yang,Guiping Jia,Fei Song,Weidong Dou,Han Huang 한국탄소학회 2023 Carbon Letters Vol.33 No.5

Graphene exhibits high carrier mobility and concentration as well as other remarkable properties. Among them, the thermal behaviors of phonon modes play important roles in the application of optical and electronic devices. Here, A–A stacked graphene were proved well by Raman investigation on G and 2D modes. Temperature-dependent Raman scattering measurements on graphene with various number of layers on different substrates were conducted in the temperature range of 80–460 K. The first-order temperature coefficient of single layer graphene (SLG) on SiO2/ Si substrate is obviously smaller than that on Cu foil, indicating that the substrate effect attributes a great impact on graphene phonon temperature dependence. The first-order temperature coefficients of multilayer graphene linearly decrease as the number of layers increases, attributed to the reduction of substrate effect in phonon behaviors, rather than to the anharmonic phonon–phonon (ph–ph) coupling or thermal expansion.