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A magnetically enabled simulation of microgravity represses the auxin response during early seed germination on a microfluidic platform

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Microsystems & Nanoengineering 2022年第1期8卷 97-109页

作者： jing du Lin Zeng Zitong yu Sihui Chen Xi Chen Yi Zhang Hui Yang Laboratory of Biomedical Microsystems and Nano Devices Center for Bionic Sensing and IntelligenceInstitute of Biomedical and Health EngineeringShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Center for Medical AI Institute of Biomedical and Health EngineeringShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

For plants on Earth,the phytohormone auxin is essential for gravitropism-regulated seedling establishment and plant ***,little is known about auxin responses under microgravity conditions due to the lack of a tool that can provide an alteration of *** this paper,a microfluidic negative magnetophoretic platform is developed to levitate Arabidopsis seeds in an equilibrium plane where the applied magnetic force compensates for gravitational *** the benefit of the microfluidic platform to simulate a microgravity environment on-chip,it is found that the auxin response is significantly repressed in levitated *** microgravity statistically interrupts auxin responses in embryos,even after chemical-mediated auxin alterations,illustrating that auxin is a critical factor that mediates the plant response to gravity ***,pretreatment with an auxin transportation inhibitor(N-1-naphthylphthalamic acid)enables a decrease in the auxin response,which is no longer affected by simulated microgravity,demonstrating that polar auxin transportation plays a vital role in gravity-regulated auxin *** presented microfluidic platform provides simulated microgravity conditions in an easy-to-implement manner,helping to study and elucidate how plants correspond to diverse gravity conditions;in the future,this may be developed into a versatile tool for biological study on a variety of samples.

关键词： magnetic auxin microgravity

Photocatalytic syngas synthesis from CO_(2) and H_(2)O using ultrafine CeO_(2)-decorated layered double hydroxide nanosheets under visible-light up to 600 nm

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 99-108页

作者： Ling Tan Kipkorir Peter jing Ren Baoyang du Xiaojie Hao yufei Zhao yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The rational design of photocatalyst that can effectively reduce CO_(2) under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch *** this work,we synthesized a series of CeO_(2)-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO_(2) *** was found that the selectivity and productivity of CO and H_(2) from photoreduction of CO_(2) in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H_(2) ratio can be widely tunable from 1/7.7 to 1/***,compared with LDH,Ce-0.15 also drove photocatalytic CO_(2) to syngas under 600 nm *** implied that an optimum amount of CeO_(2) modifying LDH promoted the photoreduction of CO_(2) to *** report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation.

关键词： visible light catalysis CO_(2)conversion layered double hydroxide rare earth elements

Intelligent Network Selection for Data Offloading in 5G Multi-Radio Heterogeneous Networks

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China Communications 2015年第S1期12卷 132-139页

作者： WU Jin LIU jing HUANG Zhangpeng du Chen ZHAO Hui BAI yu Department of Electronic Engineering Shanghai Jiao Tong University The State Key Laboratory of Integrated Service Networks Xidian University Cooperative Medianet Innovation Center Shanghai Jiao Tong University

In next generation networks, multiradio networks are emerging in order to deal with exponential data traffic increasing. Integrated Femto-WiFi(IFW) small cells have been introduced by 3GPP to offload data from cellular networks recently. These IFW cells are multi-mode capable(i.e., both licensed bands via cellular interface and unlicensed bands via WiFi interface). Therefore how to offload data effectively has become one of the most significant discussions in 5G Multi-Radio Heterogeneous Network. So far, most researches mainly focus on the generality of UEs, few attention has been paid to UEs' individual requirements. Considering UE's preference vary from individual to individual, in this paper, we present an UE preference-aware network selection scheme for mobile data offloading. It intelligently supports the distribution of heterogeneous classes of services, considers different types of UEs and delay-tolerant flows, and handles the mobility of UEs. The simulation results show the superiority of the proposed algorithm in user fairness, enhanced capacity and energy saving maximization.

关键词： LTE WiFi multi-radio hetero geneous network data offloading

COKG-QA: Multi-hop Question Answering over COVID-19 Knowledge Graphs

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Data Intelligence 2022年第3期4卷 471-492页

作者： Huifang du Zhongwen Le Haofen Wang yunwen Chen jing yu College of Design and Innovation Tongji UniversityShanghai 200092China School of Computer Science Fudan UniversityShanghai 200433China DataGrand Inc. Shanghai 201203China

COVID-19 evolves rapidly and an enormous number of people worldwide desire instant access to COVID-19 information such as the overview, clinic knowledge, vaccine, prevention measures, and COVID-19 mutation. Question answering(QA) has become the mainstream interaction way for users to consume the ever-growing information by posing natural language questions. Therefore, it is urgent and necessary to develop a QA system to offer consulting services all the time to relieve the stress of health services. In particular, people increasingly pay more attention to complex multi-hop questions rather than simple ones during the lasting pandemic, but the existing COVID-19 QA systems fail to meet their complex information needs. In this paper, we introduce a novel multi-hop QA system called COKG-QA, which reasons over multiple relations over large-scale COVID-19 Knowledge Graphs to return answers given a question. In the field of question answering over knowledge graph, current methods usually represent entities and schemas based on some knowledge embedding models and represent questions using pre-trained models. While it is convenient to represent different knowledge(i.e., entities and questions) based on specified embeddings, an issue raises that these separate representations come from heterogeneous vector spaces. We align question embeddings with knowledge embeddings in a common semantic space by a simple but effective embedding projection mechanism. Furthermore, we propose combining entity embeddings with their corresponding schema embeddings which served as important prior knowledge, to help search for the correct answer entity of specified types. In addition, we derive a large multi-hop Chinese COVID-19 dataset(called COKG-DATA for remembering) for COKG-QA based on the linked knowledge graph Open KG-COVID-19 launched by Open KG1, including comprehensive and representative information about COVID-19. COKG-QA achieves quite competitive performance in the 1-hop and 2-hop dat

关键词： COVID-19 Question answering Knowledge graph Knowledge embedding Pre-trained model Multi-hop KGQA

Response of root morphology, physiology and endogenous hormones in maize(Zea mays L.) to potassium deficiency

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Journal of Integrative Agriculture 2016年第4期15卷 785-794页

作者： ZHAO Xin-hua yu Hai-qiu WEN jing WANG Xiao-guang du Qi WANG jing WANG Qiao College of Agronomy Shenyang Agricultural University Agro-Biotechnology Research Institute Jilin Academy of Agricultural Sciences

Potassium （K） deficiency is one of the major abiotic stresses which has drastically influenced maize growth and yield around the world. However, the physiological mechanism of K deficiency tolerance is not yet fully understood. To identify the differences of root morphology, physiology and endogenous hormones at different growing stages, two maize inbred lines 90-21-3 （tolerance to K deficiency） and D937 （sensitive to K deficiency） were cultivated in the long-term K fertilizer experimental pool under high potassium （＋K） and low potassium （-K） treatments. The results indicated that the root length, volume and surface area of 90-21-3 were significantly higher than those of D937 under -K treatment at different growing stages. It was noteworthy that the lateral roots of 90-21-3 were dramatically higher than those of D937 at tasselling and flowering stage under-K treatment. Meanwhile, the values of superoxide dismutase （SOD） and oxidizing force of 90-21-3 were apparently higher than those of D937, whereas malondialdehyde （MDA） content of D937 was obviously increased. Compared with ＋K treatment, the indole-3-acetic acid （IAA） content of 90-21-3 was largely increased under-K treatment, whereas it was sharply decreased in D937. On the contrary, abscisic acid （ABA） content of 90-21-3 was slightly increased, but that of D937 was significantly increased. The zeatin riboside （ZR） content of 90-21-3 was significantly decreased, while that of D937 was relatively increased. These results indicated that the endogenous hormones were stimulated in 90-21-3 to adjust lateral root development and to maintain the physiology function thereby alleviating K deficiency.

关键词： potassium deficiency maize root morphology physiological variation endogenous hormone

Characterization of two novel heat shock protein 70s and their transcriptional expression patterns in response to thermal stress in adult of Frankliniella occidentalis (Thysanoptera:Thripidae)

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Journal of Integrative Agriculture 2018年第5期17卷 1023-1031页

作者： QIN jing GAO Peng ZHANG Xiao-xiang LU Ming-xing du yu-zhou School of Horticulture and Plant Protection & Institute of Applied Entomology Yangzhou University

Heat shock protein 70（HSP70） is one of the most important members in the heat shock protein family, and plays important roles in the thermotolerance of insect. To explore the molecular mechanism of thermotolerance of Frankliniella occidentalis adults, the difference in the expression of HSP70s in F. occidentalis male or female adults under the thermal stress was studied under the laboratory conditions. Two full length c DNAs of HSP70s gene（Fohsc704 and Fohsc705） were cloned from F. occidentalis by using RT-PCR and RACE. The genomic sequence was demonstrated by genomic validation, and the position and size of the intron were analyzed by sequence analysis of c DNA. Real-time PCR was used to analyze the HSP70 expression patterns. The c DNA of Fohsc704 and Fohsc705 possessed 2 073 and 1 476 bp which encoded 690 and 491 amino acids（aa） with a calculated molecular weight of 75 and 54 k Da, respectively. Four introns in Fohsc704 and six introns in Fohsc705 protein were found. However, the HSP70 protein sequences in our study were ended with EKKN and GIFL, which were different from the reported Fo HSP70s. Various expression patterns of Fohsc704 and Fohsc705 were found in both genders of F. occidentalis under thermal stress. The expression of Fohsc704 and Fohsc705 reached to the highest level at –12 and –8°C in male adults, respectively, and Fohsc705 expressed the highest level at 33°C in female adults. In conclusion, HSP70s of F. occidentalis in our study are novel heat shock proteins. There were difference in expression patterns of the two hsc70s in genders of F. occidentalis, and the two HSP70s play important roles in the thermotolerance of F. occidentalis.

关键词： Frankliniella occidentalis HSP70 temperature gene cloning expression

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巴西龟代谢性骨病CT诊断病例报告

动物医学进展 2025年第1期46卷 141-144页

作者：孙嘉徐甘靖宇江蓝刘波俞峰中国农业大学北京100193

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检... 详细信息

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检结果提示其肾脏、肝脏功能损害,钙磷代谢异常。CT扫查提示患龟全身组织大面积矿化、背甲凹陷,定量测量患龟背椎骨、神经骨和胸膜骨3处的骨骼密度远低于正常龟,诊断患龟有严重的MBD。治疗方案为对症治疗、改善饲养管理条件,同时对该龟补充维生素D 3。该病例报告系统陈述了龟鳖MBD的诊疗流程,同时表明了CT扫查可为龟鳖MBD精确诊断、治疗和预后提供新的参考。

关键词：龟代谢性骨病计算机断层扫描骨密度

Efficient photocatalytic reduction of chromium(Ⅵ) using photoreduced graphene oxide as photocatalyst under visible light irradiation

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Journal of Materials Science & Technology 2021年第32期91卷 17-27页

作者： Mei yu jing Shang yu Kuang Department of Environment and Health State Key Joint Laboratory of Environmental Simulation and Pollution ControlCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Graphene oxide(GO),a new and promising material,has been widely used as a co-catalyst in photocatalytic reactions;however,its capacity as a sole photocatalyst has rarely been *** this study,ultraviolet(UV) light irradiation was used as a modification method to obtain reduced GO(rGO) *** samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium(Cr(Ⅵ)) *** force microscopy(AFM),X-ray diffraction(XRD),UV-vis spectrophotometry,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and electron spin resonance(ESR) spectroscopy were applied to interpret the surface and structure changes with UV *** oxygen-containing functional groups(OFGs) on the GO surface were reduced to defective carbons andπ-conjugated C=C(sp^(2) domains) under UV light;this led to a decrease in the interlayer distance between GO sheets,GO fragmentation,and increased disorder on the GO *** restoration of sp^(2) domains led to a narrower band gap of GO,which favored the rGO excitation by visible light to generate electron-hole *** rGO pre-irradiated with UV for 1 h(rGO-1),possessing the highest defect density and electron generation efficiency,exhibited the best Cr(Ⅵ) reduction efficiency,which was about three times that of the GO sample;moreover,it outperformed most of the reported GO-based *** addition,low pH and the addition of citric acid as a hole scavenger could further improve the photocatalytic *** study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions,and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.

关键词： Graphene oxide Chromium(Ⅵ) Defect density UV-irradiation modification Photocatalytic reduction

Computer Simulation of Mechanical Properties of Nano-scale Cu/FeS Composite

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Journal of Materials Science & Technology 2010年第4期26卷 337-343页

作者： Zhenjun Hong jingchao Chen jing Feng Yeping du Jie yu Lijuan Zhang Shuzhen Wu Futai Xu Key Laboratory of Advanced Materials of Precious-Nonferrous Metals Education Ministry of China Kunming University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunming University of Science and Technology Kunming 650093 China

The mechanical properties of nano-scale Cu/FeS composite were simulated by molecular dynamics （MD） simulation in this paper. Through the analysis on the stress-strain curves, the results of MD simulation were in good agreement with mechanisms of macroscopic deformation. When the size of particles was smaller than a certain value, the relationship between yield strength and size, which was different from the large size crystals abided by the contrary Hall-Petch relationship. Based on the discussion of nano-scale Cu/FeS composite, some interesting conclusions were obtained. For example, the ＂S＂ type curves were discovered in stress-strain curves and the anisotropy of FeS was very evident when the exposures of reinforcing phase （FeS） were different and so on. The basic theories and calculations of the composite that contains nano-scale particles were discussed. At the same time, a new modeling building method of composites, which was close to actual experiences, were considered in this paper.

关键词： Nano-scale composite Mechanical properties Molecular dynamics simulation Elastic modulus Strain rigidity