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Distribution pattern and titer of Candidatus Liberibacter asiaticus in periwinkle(Catharanthus roseus)

Journal of Integrative Agriculture 2018年第11期17卷 2501-2508页

作者： LI Ya XU Mei-rong dai ze-han DENG Xiao-ling Agricultural College Guangdong Ocean University Laboratory of Citrus Huanglongbing Research/Guangdong Key Laboratory of Microbial Signals and Disease Control South China Agricultural University

Candidatus Liberibacter asiaticus （CaLas）, an uncultured Gram-negative alphaproteobacterium, is the causal agent of Huanglongbing （HLB） in citrus. CaLas resides in phloem sieve tubes and has been shown to be unequally distributed in different tissues. Although HLB is a disease of citrus plants, it has been demonstrated that periwinkle can serve as an experimental host of CaLas, which can be transmitted from citrus to periwinkle via the parasitic plant dodder （Cuscuta spp.）. To investigate the distribution of CaLas in various periwinkle tissues, the bacteria were transmitted from an infected periwinkle plant to healthy periwinkles by top-grafting. The movement of the inoculum and associated titer changes were observed over time in various tissues. CaLas could be detected in the leaves, main stems, and roots of infected periwinkle by conventional PCR, and in all three tissues a clear time-dependent change in CaLas titer was observed, with titer increasing soon after inoculation and then decreasing as disease symptoms became severe. The highest titer was found at 25, 35 and 35 days after inoculation in leaves, main stems and roots, respectively. The titer in leaves was much higher than in the main stems and roots at the same time point, and the spatial distribution of CaLas in the leaves, main stems and roots of infected periwinkle was uneven, similar to what has been shown in citrus. The results provide guidance for selecting the proper periwinkle tissues and sampling times for early detection of CaLas.

关键词： Candidatus Liberibacter asiaticus titer distribution Catharanthus roseus

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Melt flow,heat transfer and solidification in a flexible thin slab continuous casting mold with vertical-combined electromagnetic braking

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Journal of Iron and Steel Research International 2024年第2期31卷 401-415页

作者： Lin Xu ze-feng han Christian Karcher En-gang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Liaoning Province for Clean Combustion Power Generation and Heating Technology Shenyang Institute of EngineeringShenyang110136LiaoningChina Institute of Thermodynamics and Fluid Mechanics Technische Universität IlmenauIlmenau98684Germany

During continuous casting of steel slabs,the application of electromagnetic braking technology(EMBr)provides an effective tool to influence solidification by controlling the pattern of melt flow in the ***,the quality of the final product can be improved considerably.A new electromagnetic braking(EMBr)method,named vertical-combined electromagnetic braking(VC-EMBr),is proposed to be applied to a flexible thin slab casting(FTSC)*** evaluate the beneficial effects of the VC-EMBr,the melt flow,heat transfer,and solidification processes in the FTSC mold are studied by means of numerical *** detail,a Reynolds-averaged Navier–Stokes turbulence model together with an enthalpy-porosity approach was *** numerical findings are compared with respective simulations using the traditional *** results demonstrate that the application of the VC-EMBr contributes significantly to preventing relative slab *** contrast to the Ruler-EMBr,the additional vertical magnetic poles of the VC-EMBr preferentially suppress the direct impact of jet flow on the narrow face of FSTC mold and considerably diminish the level fluctuation near the meniscus *** instance,by applying a magnetic flux density of 0.3 T,the maximum amplitude of meniscus deflection reduces by about 80%.Moreover,the braking effect of the VC-EMBr effectively improves the homogeneity of temperature distribution in the upper recirculation region and increases the solidified shell thickness along the casting *** this basis,the newly proposed VC-EMBr shows a beneficial effect in preventing relative slab defects for FTSC thin slab continuous casting.

关键词： Electromagnetic braking Mold Melt flow Heat transfer Solidification

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A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun Li Ming-Yi Wu Xu han Si-Yuan He ze-Yu Lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation

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Recent advances in bioinspired vision systems with curved imaging structures

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Rare Metals 2024年第4期43卷 1407-1434页

作者： ze-Ping He Xun han Wen-Qiang Wu Zhang-Sheng Xu Cao-Feng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing100049China ZJU-hangzhou Global Scientific and Technological Innovation Center School of Micro-Nano ElectronicsZhejiang UniversityHangzhou311200China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen518060China

Limited by the planar imaging structure,the commercial camera needs to introduce additional optical elements to compensate for the curved focal plane to match the planar image *** results in a complex and bulky *** contrast,biological eyes possess a simple and compact structure due to their curved imaging structure that can directly match with the curved focal *** by the structures and functions of biological eyes,curved vision systems not only improve the image quality,but also offer a variety of advanced ***,we review the recent advances in bioinspired vision systems with curved imaging ***,we focus on their applications in implementing different functions of biological eyes,as well as the emerging curved neuromorphic imaging systems that incorporate bioinspired optical and neuromorphic processing *** addition,the challenges and opportunities of bioinspired curved imaging systems are also discussed.

关键词： Bioinspired Curved vision system Compound eye Chambered eye Neuromorphic

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A review on vanadium extraction techniques from major vanadium-containing resources

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Rare Metals 2024年第9期43卷 4115-4131页

作者： Yin-Hui Wang Yi-Fan Wang Yu-Ting Li Chang Wu Xiu-Li han Ning-Ning Zhao ze-Kun Zhang Lei dai Ling Wang Zhang-Xing He College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources Tangshan 063210China College of Chemical Engineering North China University of Science and TechnologyTangshan 063009China

The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainability of vanadium *** vanadium slag and stone coal,generated during the smelting process of vanadium–titanium magnetite,serve as primary raw materials for vanadium *** paper reviews the process mineralogy of converter vanadium slag and stone coal,encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium *** aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process *** paper systematically summarizes the current vanadium extraction technology from converter vanadium slag,covering roasting,direct leaching,sub-molten salt method,and the technology and research status of vanadium extraction from stone *** importantly,it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production,based on the analysis of the current vanadium extraction process and mechanism *** forward feasibility and prospects for the development of vanadium extraction technology are outlined.

关键词： Converter vanadium slag Stone coal Process mineralogy Vanadium extraction process Mechanism research

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Scutellarein Ameliorated Chondrocyte Inflammation and Osteoarthritis in Rats

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Current Medical Science 2024年第2期44卷 355-368页

作者： Shao-ze JING Shu-han YANG Yun-kun QU Hai-hu HAO Hua WU Department of Orthopedics Third Hospital of Shanxi Medical UniversityShanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalTaiyuan 030032China Department of Orthopedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Osteoarthritis(OA)is a degenerative joint disorder characterized by the gradual degradation of joint cartilage and local *** study aimed to investigate the anti-OA effect of scutellarein(SCU),a single-unit flavonoid compound obtained from Scutellaria barbata ***,in ***:The extracted rat chondrocytes were treated with SCU and IL-1β.The chondrocytes were divided into control group,IL-1βgroup,IL-1β+SCU 50µmol/L group,and IL-1β+SCU 100µmol/L *** of rat chondrocytes was observed by toluidine blue and safranin O ***-8 method was used to detect the cytotoxicity of ***,qRT-PCR,Western blotting,immunofluorescence,SAβ-gal staining,flow cytometry,and bioinformatics analysis were applied to evaluate the effect of SCU on rat chondrocytes under IL-1β***,anterior cruciate ligament transection(ACL-T)was used to establish a rat OA *** changes were detected by safranin O/fast green,hematoxylin-eosin(HE)staining,and ***:SCU protected cartilage and exhibited anti-inflammatory effects via multiple ***,it could enhance the synthesis of extracellular matrix in cartilage cells and inhibit its *** addition,SCU partially inhibited the nuclear factor kappa-B/mitogen-activated protein kinase(NF-κB/MAPK)pathway,thereby reducing inflammatory cytokine production in the joint ***,SCU significantly reduced IL-1β-induced apoptosis and senescence in rat chondrocytes,further highlighting its potential role in OA *** vivo experiments revealed that SCU(at a dose of 50 mg/kg)administered for 2 months could significantly delay the progression of cartilage damage,which was reflected in a lower Osteoarthritis Research Society International(OARSI)score,and reduced expression of matrix metalloproteinase 13(MMP13)in ***:SCU is effective in the therapeutic management of OA and could serve as a potential candidate f

关键词： scutellarein osteoarthritis apoptosis mitogen-activated protein kinase(MAPK) nuclear factor kappa-B(NF-κB)

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Azocalixarenes: a scaffold of universal excipients with high efficiency

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Science China Chemistry 2024年第5期67卷 1697-1706页

作者： Yu-Xin Yue Yi-Lin Lin Meng-Meng Chen han-Wen Tian Rong Ma ze-han Wang Fang-Yuan Chen Yu-Chen Pan Dong-Sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China

Excipients are important components of pharmaceutical preparations that affect their quality, safety, and efficacy. Macrocyclic receptors are a family of supramolecular excipients with several advantages, including molecular-level protection, small sizes,fast kinetics of host-guest recognition, and modular construction. With the continuous advances in the medical field, personalized and precision medicine requires the development of excipients with low dosages, integrated modifying effects, universality,and controlled release. To meet these requirements, we have developed a new family of macrocyclic excipients based on calixarenes by integrating their covalent(broad chemical design space) and noncovalent(wide range of substrates) ***, azocalixarenes(Azo CAs) were designed, showing high binding affinities to a broad spectrum of active pharmaceutical ingredients(APIs), selectivity to interferents, and responsiveness to hypoxic microenvironments. Due to their highly efficient and controllable recognition, Azo CAs serve as low-dose excipients for 30 APIs. Molecular encapsulation by Azo CAs results in the integrated modification of the physicochemical properties of APIs, including solubility, stability, bioavailability,and biocompatibility. Moreover, Azo CAs can be reduced by azoreductases overexpressed in hypoxic microenvironments,leading to the controlled release of APIs. Collectively, Azo CA excipients have broad application prospects for a series of diseases such as enteritis, arthritis, stroke, cancer, bacterial infection and kidney injury, with diverse therapeutic modalities,including chemotherapy, photodynamic therapy, photothermal therapy, immunotherapy, boron neutron capture therapy, radiotherapy, fluorescence imaging, and their combinations.

关键词： supramolecular chemistry host-guest systems excipient calixarene molecular recognition

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Simulation of rice grain breakage process based on Tavares UFRJ model

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Particuology 2024年第10期93卷 65-74页

作者： Shaohang Shen Shouyu Ji Dan Zhao Yanlong han Hao Li ze Sun Zhuozhuang Li Anqi Li Wenyu Feng Jiaming Fei Fuguo Jia Yang Li College of Engineering Northeast Agricultural UniversityHarbin150030China School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin150030China College of Food Science Northeast Agricultural UniversityHarbin150030China

Understanding the breakage characteristics of rice grains is an important means to reduce rice breakage rate. However, the dynamic breakage mechanism of rice grain is unclear due to the lack of a reasonable breakage model. In this study, the uniaxial compression test and drop weight test of single rice were carried out, the breakage model of rice grain was constructed, the reliability of rice model was verified by the experiment and simulation results. The results showed that the fracture energy distribution of rice can be obtained by uniaxial compression test, the specific fracture energy of rice accords with a lognormal distribution, and the median specific fracture energy of rice is 479.75 J/kg. The damage accumulation coefficient and fragment size distribution of rice can be acquired by drop test, the result of damage accumulation coefficient of rice was 4.3. Rice grain breakage mainly occurs in the milling section of the vertical circulation rice mill.

关键词： Rice breakage mechanism Discrete element method Parameter calibration

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Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing han ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia Zheng-Ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

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Establishment of an Iron Deficiency Model by Iron Depletion in Pregnant Rats

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Biomedical and Environmental Sciences 2024年第2期37卷 210-215页

作者： CHEN Xi han Chao ZHAO Jin Peng SHEN Shi WANG Li Yuan REN Shou WANG Tong Lei MA Yan XU ze Chao HUO Jun Sheng Key Laboratory of Trace Element Nutrition National Health Commission of the People’s Republic of ChinaNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China

Anemia,a global public health problem,has significant adverse consequences on the cognitive development of children and the work capacity of adults;affecting social and economic ***,roughly 43%of children under five years of age,38%of pregnant women,and 29%of nonpregnant women had *** during pregnancy significantly increases the risk of low birth weight and preterm birth.A 10 g/L increase in hemoglobin has been estimated to decrease the risk of maternal and perinatal mortality by 29%and 28%.

关键词： mortality pregnancy anemia

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