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Preparation, characterization and antibacterial property of naringin loaded PLGA nanospheres

Progress in Natural Science:Materials International 2022年第4期32卷 498-503页

作者： Shuo Wang Tianren Xue Baolong niu Liqiao wei Huifang Wang Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology College of Materials Science and Engineering Taiyuan University of Technology

Naringin is a predominant flavanone in grapefruit and shows a variety of biological effects such as antioxidative,anticancer, anti-inflammatory and antibacterial activity. However, its application in pharmaceutical field is limited by low water solubility, poor bioavailability and instability. To overcome the problem, naringin has been encapsulated in poly(lactic-co-glycolic acid)(PLGA) polymer by emulsion-diffusion-evaporation method in this work. Moreover, naringin loaded PLGA nanospheres were characterized by scanning electron microscope(SEM),dynamic light scatter method(DLS), fourier transform infrared(FTIR) spectra, UV–vis spectra and fluorescence spectra of DNA-EB competition displacement. The mean diameter of PLGA nanospheres and NRG/PLGA nanospheres was 123 ± 25 nm and 137 ± 30 nm, respectively. The drug encapsulation efficiency was 86.4% while the drug loading rate was 22.3%. The fluorescence spectra of the competitive DNA-binding experiments revealed that the functional activity of naringin was retained after loaded in PLGA. It is revealed that the initial burst effect happened in the initial 24 h and followed by sustained release lasting for 10 days. Moreover, the nanospheres exhibited strong antibacterial activity, and 99.9% of E. coli and S. aureus were killed when treated with naringin loaded PLGA nanospheres at the concentration of 0.2 mg mL-1within 24 h. Furthermore, the viable cells remained only 48% when the concentration of NRG/PLGA nanospheres was 32 μg m L-1and NRG/PLGA nanospheres was important for inhibition of cancer cells. It is concluded that the stable naringin loaded PLGA nanospheres could have potential application in food industry and nanomedicine field.

关键词： Naringin PLGA Nanospheres Sustained release Antibacterial activity

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菌酶复合制剂对湖羊生长性能、血清指标和粪便微生物的影响

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农业生物技术学报 2025年第1期33卷 134-145页

作者：祁帅仓振牛伟强李鹏张积鑫茆达干南京农业大学动物科技学院启东瑞鹏牧业有限公司

肉羊(Ovis aries)高度集约化养殖易导致氧化应激，机体抵抗力下降，胃肠菌群紊乱，影响生长性能。饲粮中添加菌酶复合制剂可改善肠道菌群结构，提高营养物质消化率和动物生长性能。为了探究菌酶复合制剂对湖羊生长性能、血清指标和粪便... 详细信息

肉羊(Ovis aries)高度集约化养殖易导致氧化应激，机体抵抗力下降，胃肠菌群紊乱，影响生长性能。饲粮中添加菌酶复合制剂可改善肠道菌群结构，提高营养物质消化率和动物生长性能。为了探究菌酶复合制剂对湖羊生长性能、血清指标和粪便微生物的影响，将48只2月龄的健康湖羊公羔((18.00±2.00) kg)随机分为4组，对照组饲喂基础日粮，实验组1、2、3分别添加0.1%、0.2%、0.3%菌酶复合制剂，预饲期7 d，正式期60 d。结果表明，与对照组相比，在31～60 d和1～60 d实验1和2组平均日增重(average daily gain, ADG)显著提高(P<0.05)，实验各组料重比(feed to gain ratio, F/G)均显著下降(P<0.05)；实验各组的血清白蛋白(albumin, ALB)和葡萄糖(glucose, GLU)含量均显著升高(P<0.05)，实验1组的高密度脂蛋白(high density lipoprotein, HDL)含量显著升高(P<0.05)；实验各组的超氧化物歧化酶(superoxidized dismutase, SOD)、过氧化氢酶(catalase, CAT)和谷胱甘肽过氧化物酶(glutathione peroxidase, GSH-Px)活性均显著升高(P<0.05)；实验各组的免疫球蛋白(immunoglobulin, Ig) IgA和IgG含量显著升高(P<0.05)，实验3组IgM含量显著升高(P<0.05)；实验2组的中性洗涤纤维(neutral detergent fibre, NDF)和酸性洗涤纤维(acid detergent fibre, ADF)表观消化率显著升高(P<0.05)；在门水平上，疣微菌门(Verrucomicrobiota)丰度显著提高(P<0.05)，蓝藻菌门(Cyanobacteria)和弯曲杆菌门(Campylobacterota)丰度显著降低(P<0.05)；在属水平上，另枝菌属(Alistipes)和普雷沃氏菌科UCG-001(Prevotellaceae＿UCG-001)丰度显著提高(P<0.05)，念珠菌＿糖单胞菌属(Candidatus＿Saccharimonas)丰度显著降低(P<0.05)。综上，菌酶复合制剂可提高湖羊生长性能、抗氧化和免疫能力，提高养分表观消化率，促进肠道有益菌的定植，抑制有害菌的定植，以0.2%添加量为最佳。本研究为菌酶复合制剂在湖羊生产中的应用提供科学依据。

关键词：湖羊生长性能菌酶复合制剂粪便微生物

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Observational study of the physical and chemical characteristics of the winter radiation fog in the tropical rainforest in Xishuangbanna, China

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Science China Earth Sciences 2021年第11期64卷 1982-1995页

作者： Yuan WANG Shengjie niu Chunsong LU jingjing LV jing ZHANG Hongwei ZHANG Sirui ZHANG Naifu SHAO wei SUN Yuchen jin Qinghai SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters and Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&Technology(NUIST)Nanjing 210044China College of Safety Science and Engineering Nanjing Tech UniversityNanjing 210009China Key Laboratory of Tropical Forest Ecology(TFE) Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences(CAS)Menglun 666303China Henan Meteorological Observation and Data Center Zhengzhou 450003China

We conducted a three-month field experiment focusing on the physical and chemical characteristics of fog in a tropical rainforest in Xishuangbanna,Southwest China,in the winter of *** general,the fog would form at midnight and persist because of the increased long-wave radiative cooling combined with the high relative humidity,gentle breeze,and a relatively low aerosol number concentration in the forest;the fog would dissipate before noon due to the increasing turbulence near the *** diurnal cycle is typical for radiation *** microphysical fog properties included a relatively low number concentration of the fog droplet,large droplet size,high liquid water content,narrow droplet number-size distribution,and high *** chemical properties showed that the fog water was slightly alkaline with low electrical conductivity,whereas the highest proportions of anions and cations therein were Cl^(−)and Ca^(2+),respectively;the chemical components were enriched in small fog *** addition,we indirectly calculated the fog supersaturation according to theκ-Köhler *** found that condensation broadens the droplet number-size distribution at relatively low supersaturation,which is positively correlated with the fog-droplet number concentration and negatively correlated with the droplet mean-volume diameter;this affects the key microphysical processes of fog.

关键词： Radiation fog Formation and disappearance mechanisms Physical and chemical characteristics Supersaturation Tropical rainforest

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真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响

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食品工业科技 2025年第1期46卷 97-103页

作者：徐瑞航朱立斌朱丹魏文毅牛广财赵晨雨张玙璠黑龙江八一农垦大学食品学院黑龙江大庆163319 黑龙江省农产品加工工程技术研究中心黑龙江大庆163319 黑龙江八一农垦大学生命科学技术学院黑龙江大庆163319

为探究真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响,以黄糯619和黑宝两个鲜食糯玉米品种为原料,通过扫描电子显微镜、X-射线衍射仪、傅里叶红外光谱仪、差示扫描量热仪和快速黏度分析仪等研究真空加工处理对鲜食糯玉米淀粉微观... 详细信息

为探究真空加工处理对鲜食糯玉米淀粉结构和理化性质的影响,以黄糯619和黑宝两个鲜食糯玉米品种为原料,通过扫描电子显微镜、X-射线衍射仪、傅里叶红外光谱仪、差示扫描量热仪和快速黏度分析仪等研究真空加工处理对鲜食糯玉米淀粉微观结构和理化性质的影响。结果表明:真空加工处理使黄糯619和黑宝2种鲜食糯玉米的直链淀粉含量显著升高(P<0.05),分别由5.39%和6.26%升高至8.52%和9.71%,支链淀粉含量显著降低(P<0.05),分别由94.61%和93.74%降低至91.48%和90.29%,淀粉颗粒破坏严重,淀粉的晶体类型和官能团结构没有改变,但相对结晶度分别降低了9.62%和9.41%;真空加工处理后,2种鲜食糯玉米淀粉的起始温度、峰值温度、终止温度和糊化焓值显著下降(P<0.05),淀粉的糊化温度、峰值黏度、最终黏度、衰减值、回生值显著下降(P<0.05),表明淀粉更容易发生糊化,抗老化能力增强。此外,真空加工处理使鲜食糯玉米淀粉的抗性淀粉(RS)转变为快消化淀粉(RDS)和慢消化淀粉(SDS),说明真空加工处理能够提高鲜食糯玉米淀粉的消化速率。本实验结果可以为鲜食糯玉米真空加工与利用提供理论依据。

关键词：鲜食糯玉米真空加工处理淀粉结构理化性质

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Improved tensile properties of Al_(0.5)CoCrFeNi high-entropy alloy by tailoring microstructures

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Rare Metals 2021年第9期40卷 2508-2513页

作者： Si-Zhe niu Hong-Chao Kou Jun Wang jin-Shan Li State Key Laboratory of Solidiﬁcation Processing Northwestern Polytechnical UniversityXi’an 710072China

The effect of heat treatment on microstructure and tensile properties of as-cast Al_(0.5)CoCrFeNi high-entropy alloy was investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS), and tensile *** results show that heat treatment strongly affects the microstructure, particularly the morphology of bcc phases,and improves tensile properties. Microstructure analysis reveals that rod-shaped and elliptoid phases appear in the matrix after heat treatment at 1150 ℃. Besides, under850 ℃ heat-treated condition, ultimate tensile strength increases by about 60% without sacrificing much plasticity,which can be attributed to the content of bcc phases and fine precipitates dispersed in the dendrites. For other heattreated conditions, tensile ductility increases by at least30%, especially 60% for heat treatment at 450 ℃, and strength also improves. Fracture analysis indicates that the fracture mode of heat treatment at 850 ℃ is a mixture of quasi-cleavage and ductile fracture, while the other heattreated conditions show the mode of ductile fracture.

关键词： High-entropy alloys Heat treatment Microstructure Tensile properties

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A Preliminary Calculation of Three-Dimensional Unsteady Underwater Cavitating Flows Near Incompressible Limit

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Communications in Computational Physics 2008年第9期4卷 894-910页

作者： Yang-Yao niu wei-Yuan Hsu Department of Mechanical Engineering Chung-Hua UniversityHsin-ChuTaiwan30067ROC.

Recently,cavitated flows over underwater submerged bodies have attracted researchers to simulate large scale *** Computational Fluid Dynamics(CFD)approaches have been used widely and successfully to model developed ***,it is still a great challenge to accurately predict cavitated flow phenomena associated with interface capturing,viscous effects,unsteadiness and *** this study,we consider the preconditioned three-dimensional multiphase Navier-Stokes equations comprised of the mixture density,mixture momentum and constituent volume fraction equations.A dual-time implicit formulation with LU Decomposition is employed to accommodate the inherently unsteady ***,we adopt the Roe flux splitting method to deal with flux discretization in ***,time-derivative preconditioning is used to ensure well-conditioned eigenvalues of the high density ratio two-phase flow system to achieve computational *** cases include an unsteady 3-D cylindrical headform cavitated flow and an 2-D convergent-divergent nozzle channel cavity-problem.

关键词： Cavitation incompressible Roe Riemann solver dual-time stepping

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Regulation of antibiotic biosynthesis in actinomycetes:Perspectives and challenges

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Synthetic and Systems Biotechnology 2018年第4期3卷 229-235页

作者： Junhong wei Lang He Guoqing niu Biotechnology Research Center Southwest UniversityChongqing400715China State Key Laboratory of Silkworm Genome Biology Southwest UniversityChongqing400715China Academy of Agricultural Sciences Southwest UniversityChongqing400715China

Actinomycetes are the main sources of *** onset and level of production of each antibiotic is subject to complex control by multi-level *** regulators exert their functions at hierarchical *** the lower level,cluster-situated regulators(CSRs)directly control the transcription of neighboring genes within the gene ***-level pleiotropic and global regulators exert their functions mainly through modulating the transcription of *** in understanding of the regulation of antibiotic biosynthesis in actinomycetes have inspired us to engineer these regulators for strain improvement and antibiotic discovery.

关键词： Antibiotic biosynthesis Regulation Actinomycetes Genetic manipulation Strain improvement Antibiotic discovery

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Effect of multilayer graphene/nano-Fe2O3 composite additions on dry sliding wear behavior of titanium matrix composites

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Journal of Iron and Steel Research International 2020年第9期27卷 1117-1126页

作者： Huang Xie Yun-xue jin Mu-ye niu Ji-heng Wang School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina National Demonstration Center for Experimental Materials Science and Engineering Education(Jiangsu University of Science and Technology) Zhenjiang 212003JiangsuChina

The wear tests of titanium matrix composites(TMCs)at the loads of 50,100,120,and 150 N were carried out with an MMW-1 vertical universal friction and wear tester to study the addition of multilayer graphene(MLG)/nano-Fe2O3 composites(0,0.1,0.2,0.3,0.4,and 0.5 g)on the dry sliding wear behavior of *** presented a marked variation in wear loss as a function of the amount of MLG/Fe2O3 addition,and a significant decrease in the friction coefficient was obtained,reducing this parameter up to 50%.With the rise and fall of wear loss,TMCs underwent a transition from severe wear to mild *** phenomena were attributed to the existence of a protective lubricating film,which prevented the surface from coming in direct contact,and the lubricating film was 15-20μm thick and made up of MLG/Fe2O3(1:2)*** structure was speculated to be similar to a rolling wood.

关键词： Titanium matrix composite Graphene Nanomaterial Lubricating film Wear behavior

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UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu Wen-jin niu Ye Zhu Hong-Bo Zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

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Resistance risk and molecular mechanism associated with resistance to picoxystrobin in Colletotrichum truncatum and Colletotrichum gloeosporioides

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Journal of Integrative Agriculture 2023年第12期22卷 3681-3693页

作者： SHI niu-niu LIAN jin-pan QIU De-zhu CHEN Fu-ru DU Yi-xin Institute of Plant Protection Fujian Academy of Agricultural SciencesFuzhou 350013P.R.China Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests Fuzhou 350013P.R.China Crop Research Institute Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002P.R.China

Anthracnose,caused by Colletotrichum truncatum and ***,is amongst the most serious diseases of soybean in ***,a quinone outside inhibitor fungicide,is commonly used for the control of *** resistance risk and mechanism in *** and *** are *** this study,the sensitivities of 128 *** and 121 *** isolates to picoxystrobin were investigated,and unimodal distributions were observed with average EC_(50)values of 0.7740 and 1.1561μg mL^(-1),*** picoxystrobin-resistant mutants of *** and six mutants of *** were acquired,with EC_(50)values varying from 5.40-152.96 and 13.53-28.30μg mL^(-1),*** to the parental isolates,mutants showed similar or higher relative fitness in conidial production and germination,and ***,the resistance risk of *** and *** to picoxystrobin is moderate to *** was positive cross-resistance between picoxystrobin and pyraclostrobin,but not between picoxystrobin and fluazinam,difenoconazole,or *** G143S mutation in Cyt b protein was detected in seven high-resistant mutants of ***(RF>100),and G137R occurred in four moderate-resistant mutants(RF<_(50)).Contrastingly,there were no point mutations in Cyt b of any *** *** docking confirmed that two mutations conferred different resistance levels to *** greenhouse trials,picoxystrobin did not control mutants with the G143S mutation,those bearing G137R or no point mutation were somewhat controlled,but at a lower level compared to wild-type *** results showed that integrated management strategies should be implemented to preserve fungicide effectiveness.

关键词： Colletotrichum truncatum Colletotrichum gloeosporioides picoxystrobin point mutation Cyt b molecular docking

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