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Polycomb-group （Pc-G） Proteins Control Seed Development in Arabidopsis thaliana L.

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Journal of Integrative Plant Biology 2007年第1期49卷 52-59页

作者： Xiao-xue Wang Li-geng Ma National Institute of Biological Sciences Beijing 102206 China

Polycomb-group （Pc-G） proteins repress their target gene expression by assemble complexes in Drosophila and mammals. Three groups of Pc-G genes, controlling seed development, flower development and vernalization response, have been identified in Arabidopsis （Arabidopsis thaliana L.）. MEDEA （MEA）, FERTILIZATION INDEPENDENT SEED2 （FIS2）, and FERTILIZATION INDEPENDENT ENDOSPERM （FIE） are Pc-G genes in Arabidopsis. Their functions in seed development have been extensively explored. The advanced findings of molecular mechanism on how MEA, FIS2 and FIE control seed development in Arabidopsis are reviewed in this paper.

关键词： Arabidopsis FIS1/MEA FIS2 FIS3/FIE Pc-G genes

Improved formation density measurement using controllable D-D neutron source and its lithological correction for porosity prediction

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Nuclear Science and Techniques 2022年第1期33卷 24-34页

作者： Li Zhang Hua-Wei Yu Yang Li Wen-Bao Jia Xiao Han xue-Sen geng College of Resources Shandong University of Science and TechnologyTai’an 271019China School of Geosciences China University of PetroleumQingdao 266580China College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Department of Nuclear Science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Controllable D-D neutron sources have a long service life,low cost,and *** are favorable prospects for its application in geophysical well logging,since traditional chemical radioactive sources used for well logging pose potential threats to the safety of the human body and *** paper presents an improved method to measure formation density that employs a D-D neutron *** addition,the lithological effect on the measured density was removed to better estimate the formation ***,we investigated the spatial distribution of capture gamma rays through Monte Carlo simulations as well as the relationship between the ratio of capture gamma ray counts and formation density to establish theoretical support for the design of density logging tools and their corresponding data processing ***,we obtained the far to near detector counts of captured gamma rays for an optimized tool structure and then established its correlation with the density and porosity of three typical formations with pure quartz,calcite,and dolomite ***,we determined the values for correcting the densities of sandstone and dolomite with the same porosity using limestone data as the reference and established the equations for calculating the correction values,which lays a solid foundation for accurately calculating formation *** observed that the capture gamma ray counts first increased then decreased and varied in different formations;this was especially observed in high-porosity *** the same lithologic conditions(rock matrix),as the porosity increases,the peak value of gamma ray counts moves toward the neutron *** different detector-source distances,the ratio of the capture gamma ray counts was well correlated with the formation *** equation of the formation density conversion was established based on the ratio of capture gamma ray counts at the detector-source distances of 30 cm and 65 cm,and the calculate

关键词： Density measurement D-D neutron source Lithological correction Porosity prediction

Learning multiple metrics for ranking

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Frontiers of Materials Science 2011年第3期5卷 259-267页

作者： Xiubo geng xue-Qi CHENG Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Directly optimizing an information retrieval （IR） metric has become a hot topic in the field of learning to rank. Conventional wisdom believes that it is better to train for the loss function on which will be used for evaluation. But we often observe different results in reality. For example, directly optimizing averaged preci- sion achieves higher performance than directly optimizing precision@3 when the ranking results are evaluated in terms of precision@3. This motivates us to combine multiple metrics in the process of optimizing IR metrics. For simplicity we study learning with two metrics. Since we usually conduct the learning process in a restricted hypothesis space, e.g., linear hypothesis space, it is usually difficult to maximize both metrics at the same time. To tackle this problem, we propose a relaxed approach in this paper. Specifically, we incorporate one metric within the constraint while maximizing the other one. By restricting the feasible hypothesis space, we can get a more robust ranking model. Empirical results on the benchmark data set LETOR show that the relaxed approach is superior to the direct linear combination approach, and also outperforms other baselines.

关键词： leaming to rank multiple measures directoptimization

The multifunctional wound dressing with core-shell structured fibers prepared by coaxial electrospinning

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Frontiers of Materials Science 2016年第2期10卷 113-121页

作者： Qilin WEI Feiyang XU Xingjian XU xue geng Lin YE Aiying ZHANG Zengguo FENG School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications Beijing 100081 China

The non-woven wound dressing with core-shell structured fibers was prepared by coaxial electrospinning. The polycaprolactone （PCL） was electrospun as the fiber＇s core to provide mechanical strength whereas collagen was fabricated into the shell in order to utilize its good biocompatibility. Simultaneously, the silver nanoparticles （Ag- NPs） as anti-bacterial agent were loaded in the shell whereas the vitamin A palmitate （VA） as healing-promoting drug was encapsulated in the core. Resulting from the fiber＇s core- shell structure, the VA released from the core and Ag-NPs present in the shell can endow the dressing both heal-promoting and anti-bacteria ability simultaneously, which can greatly enhance the dressing＇s clinical therapeutic effect. The dressing can maintain high swelling ratio of 190% for 3 d indicating its potential application as wet dressing. Furthermore, the dressing＇s anti-bacteria ability against Staphylococcus aureus was proved by in vitro anti-bacteria test. The in vitro drug release test showed the sustainable release of VA within 72 h, while the cell attachment showed L929 cells can well attach on the dressing indicating its good biocompatibility. In conclusion, the fabricated nanofibrous dressing possesses multiple functions to benefit wound healing and shows promising potential for clinical application.

关键词： coaxial electrospinning core-shell structure multifunctional wounddressing anti-bacteria heal-promoting

Integrin beta 3-overexpressing mesenchymal stromal cells display enhanced homing and can reduce atherosclerotic plaque

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World Journal of Stem Cells 2023年第9期15卷 931-946页

作者： Hai-Juan Hu xue-Ru Xiao Tong Li De-Min Liu xue geng Mei Han Wei Cui First Division Department of CardiologyThe Second Hospital of Hebei Medical University and Institute of Cardiocerebrovascular Disease of Hebei ProvinceShijiazhuang 050000Hebei ProvinceChina Department of Obstetrics Shijiazhuang People's HospitalShijiazhuang 050030Hebei ProvinceChina Key Laboratory of Medical Biotechnology of Hebei Province Department of Biochemistry and Molecular BiologyCollege of Basic MedicineCardiovascular Medical Science CenterHebei Medical UniversityShijiazhuang 050017Hebei ProvinceChina

BACKGROUND Umbilical cord(UC)mesenchymal stem cell(MSC)transplantation is a potential therapeutic intervention for atherosclerotic vascular *** beta 3(ITGB3)promotes cell migration in several cell ***,whether ITGBmodified MSCs can migrate to plaque sites in vivo and play an anti-atherosclerotic role remains *** To investigate whether ITGB3-overexpressing MSCs(MSCs^(ITGB3))would exhibit improved homing efficacy in *** UC MSCs were isolated and *** vectors encoding ITGB3 or green fluorescent protein(GFP)as control were transfected into *** male apolipoprotein E-/-mice were acquired from Beijing Vital River Lab Animal Technology Co.,Ltd and fed with a high-fat diet(HFD)for 12 wk to induce the formation of atherosclerotic *** HFD-fed mice were randomly separated into three ***-labeled MSCs(MSCs^(GFP))or MSCs^(ITGB3)were transplanted into the mice intravenously via the tail *** staining,Oil red O staining,histological analyses,western blotting,enzymelinked immunosorbent assay,and quantitative real-time polymerase chain reaction were used for the *** ITGB3 modified MSCs successfully differentiated into the“osteocyte”and“adipocyte”phenotypes and were characterized by positive expression(>91.3%)of CD29,CD73,and CD105 and negative expression(<1.35%)of CD34 and Human Leukocyte *** a transwell assay,MSCs^(ITGB3)showed significantly faster migration than ***3 overexpression had no effects on MSC viability,differentiation,and *** staining revealed that ITGB3 overexpression substantially enhanced the homing of MSCs to plaque *** red O staining and histological analyses further confirmed the therapeutic effects of MSCs^(ITGB3),significantly reducing the plaque ***-linked immunosorbent assay and quantitative real-time polymerase chain reaction revealed that MSC^(ITGB3)transplantation considerably decr

关键词： Atherosclerosis Inflammation Integrin beta 3 Mesenchymal stem cells Arg-Gly-Asp structure Umbilical cord

The feasibility analysis of the application of TPV system in reentry

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Science China(Technological Sciences) 2010年第12期53卷 3310-3315页

作者： YE Hong & geng xue Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, China 1. Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 China

A fundamental design of using thermophotovoltaic (TPV) system to convert the huge aerodynamic heat into electricity during the reentry process was described. The influences of heat conducting way, spectral filter and selective radiating surface on the system performance were analyzed in detail. The results showed that as a thermal conducting component, SiC is better than ablation material, with more electricity output but a larger cooling load, and that the adoption of spectral filter and selective radiating surface could lower the power output to some extent, yet diminish the cooling load prominently.

关键词： TPV reentry process spectral filter selective radiating surface

Protective effects on acute hypoxic-ischemic brain damage in mfat-1 transgenic mice by alleviating neuroinflammation

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The Journal of Biomedical Research 2021年第6期35卷 474-490页

作者： xue geng Meng Wang Yunjun Leng Lin Li Haiyuan Yang Yifan Dai Ying Wang Jiangsu Key Laboratory of Xenotransplantation Nanjing Medical UniversityNanjingJiangsu 211166China Key Laboratory of Targeted Intervention of Cardiovascular Disease Collaborative Innovation Center for Cardiovascular Disease Translational MedicineNanjing Medical UniversityNanjingJiangsu 211166China.

Acute hypoxic-ischemic brain damage(HIBD)mainly occurs in adults as a result of perioperative cardiac arrest and *** benefits of n-3 polyunsaturated fatty acids(n-3 PUFAs)in maintaining brain growth and development are well ***,possible protective targets and underlying mechanisms of mfat-1 mice on HIBD require further *** mfat-1 transgenic mice exhibited protective effects on HIBD,as indicated by reduced infarct range and improved neurobehavioral ***-seq analysis showed that multiple pathways and targets were involved in this process,with the anti-inflammatory pathway as the most *** study has shown for the first time that mfat-1 has protective effects on HIBD in *** of a G protein-coupled receptor 120(GPR120)-related anti-inflammatory pathway may be associated with perioperative and postoperative complications,thus innovating clinical intervention strategy may potentially benefit patients with HIBD.

关键词： hypoxic-ischemic brain damage mfat-1 transgenic mice n-3 PUFAs RNA-seq neuroinflammation GPR120 receptor

Design and fabrication of smart functional hydrogel wound dressing for diabetic foot ulcer

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Frontiers of Materials Science 2024年第3期18卷 1-18页

作者： Yufei Wang Dandan Hou Hui Zhao xue geng Xin Wu Gaobiao Li Fei Sha Zengguo Feng Zongjian Liu Lin Ye School of Materials Science and Engineering Bejing Institute of TechnologyBeijing 100081China SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013China Department of Vascular Surgery Beijing Luhe HospitalCapital Medical UniversityBeijing 101100China Department of Vascular Surgery Wangjing HospitalChina Academy of Chinese Medical SciencesBejing 100102China Beijing Rehabilitation Hospital Capital Medical UniversityBeijing 100044China

Diabetic foot ulcer(DFU)often evolves into chronic wounds that resist healing over an extended period,sometimes necessitating amputation in severe *** wound management approaches generally fail to control these chronic sores ***,it arouses a huge demand in clinic for a novel wound dressing to treat DFU *** as an ideal delivery system exhibits excellent loading capacity and sustainable release *** also boasts tunable physical and chemical properties adaptable to diverse biomedical scenarios,making it a suitable material for fabricating functional wound dressings to treat *** hydrogel dressings are classified into hemostatic,antibacterial and anti-inflammatory,and healing-promoting hydrogel dressings by associating the pathogenesis of DFU in this *** design and fabrication strategies for the dressings,as well as their therapeutic effects in treating DFU,are extensively ***,this paper highlights future perspectives of multifunctional hydrogel dressings in DFU *** review aims to provide valuable references for material scientists to design and develop hydrogel wound dressings with enhanced capabilities for DFU treatment,and to further translate them intothe clinic inthefuture.

关键词： hydrogel dressing multifunction design fabrication diabetic foot ulcer

Influence of groundwater level changes on the seismic response of geosynthetic-reinforced soil retaining walls

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 850-862页

作者： Fei-fan REN Qiang-qiang HUANG xue-yu geng Guan WANG Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai 200092China School of Engineering University of WarwickCoventry CV47ALUK School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai 200093China

Geosynthetic-reinforced soil retaining walls(GSRWs)have been widely used in civil engineering ***,as the climate changes,extreme weather conditions and natural hazards are likely to become more frequent or intense,posing a huge threat to the stability of *** this paper,the effect of groundwater level fluctuations on the seismic response of GSRWs is ***,a dynamic numerical model was established and validated through centrifugal shaking-table test *** the established numerical model,the seismic response of GSRWs under four different groundwater level conditions was then investigated,i.e.,an earthquake occurring at a low groundwater level(Case LW),an earthquake occurring when the groundwater level rises(Case RW),an earthquake occurring at a high groundwater level(Case HW),and an earthquake occurring when the groundwater level drops(Case DW).The results show that the GSRW in Case DW has the worst seismic stability because of the drag forces generated by the water flowing to the outside of the *** Case RW,deformation of the GSRW under earthquake forces was prevented by the drag forces generated by the water flowing to the inside of the GSRW and the water pressure acting on the outside of the facing,giving the GSRW the best seismic stability in this *** with Case LW,the seismic stability of a GSRW in Case HW is worse,because the high groundwater level will generate excess pore-water pressure during an *** this basis,we provide engineering design suggestions to be considered by practitioners.

关键词： Geosynthetic-reinforced soil retaining walls(GSRWs) Groundwater level Earthquake Stability analysis