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Flow Regimes in Bubble Columns with and without Internals: A Review 被引量:1
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作者 Ayat N.Mahmood Amer A.Abdulrahman +3 位作者 Laith S.Sabri Abbas J.Sultan Hasan Shakir Majdi Muthanna H.Al-Dahhan 《Fluid Dynamics & Materials Processing》 EI 2024年第2期239-256,共18页
Hydrodynamics characterization in terms offlow regime behavior is a crucial task to enhance the design of bubble column reactors and scaling up related methodologies.This review presents recent studies on the typicalflo... Hydrodynamics characterization in terms offlow regime behavior is a crucial task to enhance the design of bubble column reactors and scaling up related methodologies.This review presents recent studies on the typicalflow regimes established in bubble columns.Some effort is also provided to introduce relevant definitions pertaining to thisfield,namely,that of“void fraction”and related(local,chordal,cross-sectional and volumetric)variants.Experimental studies involving different parameters that affect design and operating conditions are also discussed in detail.In the second part of the review,the attention is shifted to cases with internals of various types(perfo-rated plates,baffles,vibrating helical springs,mixers,and heat exchanger tubes)immersed in the bubble columns.It is shown that the presence of these elements has a limited influence on the global column hydrodynamics.However,they can make the homogeneousflow regime more stable in terms of transition gas velocity and transi-tion holdup value.The last section is used to highlight gaps which have not beenfilled yet and future directions of investigation. 展开更多
关键词 HYDRODYNAMICS flow regime bubble column heat-exchanging internals
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Reversible solid-liquid conversion enabled by self-capture effect for stable non-flow zinc-bromine batteries 被引量:1
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作者 Xixi Zhang Xiaoke Wang +7 位作者 Guangmeng Qu Tairan Wang Xiliang Zhao Jun Fan Cuiping Han Xijin Xu Chunyi Zhi Hongfei Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1035-1044,共10页
Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfort... Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfortunately,they generally suffer from serious diffusion and shuttle of polybromide(Br^(-),Br^(3-))due to the weak physical adsorption between soluble polybromide and host carbon materials,which results in low energy efficiency and poor cycling stability.Here,we develop a novel self-capture organic bromine material(1,10-bis[3-(trimethylammonio)propyl]-4,4'-bipyridinium bromine,NVBr4)to successfully realize reversible solid complexation of bromide components for stable non-flow zinc-bromine battery applications.The quaternary ammonium groups(NV^(4+)ions)can effectively capture the soluble polybromide species based on strong chemical interaction and realize reversible solid complexation confined within the porous electrodes,which transforms the conventional“liquid-liquid”conversion of soluble bromide components into“liquid-solid”model and effectively suppresses the shuttle effect.Thereby,the developed non-flow zinc-bromide battery provides an outstanding voltage platform at 1.7 V with a notable specific capacity of 325 mAh g^(-1)NVBr4(1 A g^(-1)),excellent rate capability(200 mAh g^(-1)NVBr4 at 20 A g^(-1)),outstanding energy density of 469.6 Wh kg^(-1)and super-stable cycle life(20,000 cycles with 100%Coulombic efficiency),which outperforms most of reported zinc-halogen batteries.Further mechanism analysis and DFT calculations demonstrate that the chemical interaction of quaternary ammonium groups and bromide species is the main reason for suppressing the shuttle effect.The developed strategy can be extended to other halogen batteries to obtain stable charge storage. 展开更多
关键词 Solid-liquid conversion Self-capture Non-flow zinc-bromine batteries Quaternary ammonium
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基于VRB/OW-GFRP混合结构的CTB电池包上盖总成轻量化设计研究
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作者 段利斌 张雨 +5 位作者 杜展鹏 刘冶钢 孟祥新 田冠男 郑海洋 吴闯 《汽车工程》 EI CSCD 北大核心 2024年第2期290-299,共10页
电池车身一体化(CTB)是提升电动汽车续航里程的关键技术。利用胶接工艺将变厚度(VRB)结构与正交编织玻璃纤维增强复合材料(OW-GFRP)粘接形成的VRB/OW-GFRP混合结构,是降低CTB电池包质量的创新结构,有助于进一步提升电动汽车的续航里程... 电池车身一体化(CTB)是提升电动汽车续航里程的关键技术。利用胶接工艺将变厚度(VRB)结构与正交编织玻璃纤维增强复合材料(OW-GFRP)粘接形成的VRB/OW-GFRP混合结构,是降低CTB电池包质量的创新结构,有助于进一步提升电动汽车的续航里程。以某款电动汽车为研究对象,设计了一种CTB电池车身一体化结构,实现了电池包上盖与车身地板的集成融合。分别采用VRB结构、UT/OW-GFRP及VRB/OW-GFRP混合结构替代等厚度(UT)CTB电池包上盖总成,并基于多阶段优化方法开展了3种类型CTB电池包上盖总成的轻量化设计。结果表明,在满足CTB电池包刚度性能前提下,VRB结构相比UT结构实现减质量6.4%;基于VRB/OW-GFRP混合结构的CTB电池包上盖总成轻量化效果约为金属结构的3倍,VRB/OW-GFRP相比UT/OW-GFRP混合电池包上盖总成进一步减质量4.2%。由此可见,VRB/OW-GFRP混合结构是未来汽车轻量化技术发展的重要趋势,在CTB电池包上盖总成中具有巨大的应用前景。 展开更多
关键词 变厚度/正交编织玻璃纤维增强复合材料 混合结构 电池车身一体化 电池包 轻量化
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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类风湿关节炎合并骨关节炎病人血清anti-Sa、anti-CCP水平与骨关节损伤、全身炎症反应的相关性分析
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作者 玛依拉·艾尼瓦尔 古丽美热·艾买如拉 +2 位作者 何雪娇 张裕祥 赵婷 《蚌埠医学院学报》 CAS 2024年第5期645-648,共4页
目的:分析类风湿关节炎(RA)病人血清anti-Sa、anti-CCP抗体水平与其骨关节损伤、全身炎症反应的相关性。方法:选择RA合并骨关节损伤病人108例,根据血清anti-Sa、anti-CCP抗体水平分别列入高anti-Sa组和低anti-Sa组、高anti-CCP组和低ant... 目的:分析类风湿关节炎(RA)病人血清anti-Sa、anti-CCP抗体水平与其骨关节损伤、全身炎症反应的相关性。方法:选择RA合并骨关节损伤病人108例,根据血清anti-Sa、anti-CCP抗体水平分别列入高anti-Sa组和低anti-Sa组、高anti-CCP组和低anti-CCP组。比较各组病人WOMAC骨性关节炎指数、lysholms膝关节功能评分值,血清白细胞介素(IL)-1β、IL-6、IL-27、肿瘤坏死因子α(TNF-α)水平。采用Pearson检验评估有关指标的相关性。结果:高anti-Sa组、高anti-CCP组病人的WOMAC骨性关节炎指数明显高于低anti-Sa组(P<0.01),lysholms膝关节功能评分明显低于低anti-Sa组(P<0.01);血清中IL-1β、IL-6、IL-27、TNF-α的水平明显高于低anti-CCP组(P<0.01)。RA病人血清anti-Sa、anti-CCP抗体水平与骨关节损伤、全身炎症反应严重程度呈正相关关系(P<0.05~P<0.01),与lysholms膝关节功能评分呈负相关关系(P<0.01)。结论:RA病人血清中anti-Sa、anti-CCP抗体水平显著升高与关节损伤及全身炎症反应有一定的相关性,可作为临床判断病情活动性与骨关节损伤的参考指标。 展开更多
关键词 类风湿性关节炎 骨关节损伤 全身炎症反应 anti-SA anti-CCP
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Double-Doped Carbon-Based Electrodes with Nitrogen and Oxygen to Boost the Areal Capacity of Zinc-Bromine Flow Batteries
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作者 Xiaoyun Sun Deren Wang +4 位作者 Haochen Hu Xin Wei Lin Meng Zhongshan Ren Sensen Li 《Transactions of Tianjin University》 EI CAS 2024年第1期74-89,共16页
Ensuring a stable power output from renewable energy sources,such as wind and solar energy,depends on the development of large-scale and long-duration energy storage devices.Zinc–bromine fl ow batteries(ZBFBs)have em... Ensuring a stable power output from renewable energy sources,such as wind and solar energy,depends on the development of large-scale and long-duration energy storage devices.Zinc–bromine fl ow batteries(ZBFBs)have emerged as cost-eff ective and high-energy-density solutions,replacing expensive all-vanadium fl ow batteries.However,uneven Zn deposition during charging results in the formation of problematic Zn dendrites,leading to mass transport polarization and self-discharge.Stable Zn plating and stripping are essential for the successful operation of high-areal-capacity ZBFBs.In this study,we successfully synthesized nitrogen and oxygen co-doped functional carbon felt(NOCF4)electrode through the oxidative polymerization of dopamine,followed by calcination under ambient conditions.The NOCF4 electrode eff ectively facilitates effi cient“shuttle deposition”of Zn during charging,signifi cantly enhancing the areal capacity of the electrode.Remarkably,ZBFBs utilizing NOCF4 as the anode material exhibited stable cycling performance for 40 cycles(approximately 240 h)at an areal capacity of 60 mA h/cm^(2).Even at a high areal capacity of 130 mA h/cm^(2),an impressive energy effi ciency of 76.98%was achieved.These fi ndings provide a promising pathway for the development of high-areal-capacity ZBFBs for advanced energy storage systems. 展开更多
关键词 Zinc-bromine fl ow batteries N O co-doping Areal capacity Shuttle deposition Zinc dendrite
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Analysis of Snow Distribution and Displacement in the Bogie Region of a High-Speed Train
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作者 Zhihui Du Mengge Yu +1 位作者 Jiali Liu Xiulong Yao 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1687-1701,共15页
Snow interacting with a high-speed train can cause the formation of ice in the train bogie region and affect its safety.In this study,a wind-snow multiphase numerical approach is introduced for high-speed train bogies... Snow interacting with a high-speed train can cause the formation of ice in the train bogie region and affect its safety.In this study,a wind-snow multiphase numerical approach is introduced for high-speed train bogies on the basis of the Euler-Lagrange discrete phase model.A particle-wall impact criterion is implemented to account for the presence of snow particles on the surface.Subsequently,numerical simulations are conducted,considering various snow particle diameter distributions and densities.The research results indicate that when the particle diameter is relatively small,the distribution of snow particles in the bogie cavity is relatively uniform.However,as the particle diameter increases,the snow particles in the bogie cavity are mainly located in the rear wheel pairs of the bogie.When the more realistic Rosin-Rammler diameter distribution is applied to snow particles,the positions of snow particles with different diameters vary in the bogie cavity.More precisely,smaller diameter particles are primarily located in the front and upper parts of the bogie cavity,while larger diameter snow particles accumulate at the rear and in the lower parts of the bogie cavity. 展开更多
关键词 BOGIE the wind-snow multiphaseflow model particle diameter distribution
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Pairing nitroxyl radical and phenazine with electron-withdrawing/-donating substituents in “water-in-ionic liquid” for high-voltage aqueous redox flow batteries
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作者 Zhifeng Huang Rolf Hempelmann +2 位作者 Yiqiong Zhang Li Tao Ruiyong Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期713-722,共10页
Aqueous redox-active organic materials-base electrolytes are sustainable alternatives to vanadium-based electrolyte for redoxflow batteries(RFBs)due to the advantages of high ionic conductivity,environmentally benign,s... Aqueous redox-active organic materials-base electrolytes are sustainable alternatives to vanadium-based electrolyte for redoxflow batteries(RFBs)due to the advantages of high ionic conductivity,environmentally benign,safety and low cost.However,the underexplored redox properties of organic materials and the narrow thermodynamic electrolysis window of water(1.23 V)hinder their wide applications.Therefore,seeking suitable organic redox couples and aqueous electrolytes with a high output voltage is highly suggested for advancing the aqueous organic RFBs.In this work,the functionalized phenazine and nitroxyl radical with electron-donating and electron-withdrawing group exhibit redox potential of-0.88 V and 0.78 V vs.Ag,respectively,in“water-in-ionic liquid”supporting electrolytes.Raman spectra reveal that the activity of water is largely suppressed in“water-in-ionic liquid”due to the enhanced hydrogen bond interactions between ionic liquid and water,enabling an electrochemical stability window above 3 V.“Water-in-ionic liquid”supporting electrolytes help to shift redox potential of nitroxyl radical and enable the redox activity of functionalized phenazine.The assembled aqueous RFB allows a theoretical cell voltage of 1.66 V and shows a practical discharge voltage of 1.5 V in the“water-in-ionic liquid”electrolytes.Meanwhile,capacity retention of 99.91%per cycle is achieved over 500 charge/discharge cycles.A power density of 112 mW cm^(-2) is obtained at a current density of 30 mA cm^(-2).This work highlights the importance of rationally combining supporting electrolytes and organic molecules to achieve high-voltage aqueous RFBs. 展开更多
关键词 Aqueous redoxflow batteries Water-in-ionic liquid electrolytes High-voltage aqueous batteries Organic redox-active materials
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Simulation of Two-Phase Flowback Phenomena in Shale Gas Wells
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作者 Yongwei Duan Zhaopeng Zhu +2 位作者 Hui He Gaoliang Xuan Xuemeng Yu 《Fluid Dynamics & Materials Processing》 EI 2024年第2期349-364,共16页
The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework... The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model(EDFM).This model assumes the region outside the stimulated reservoir volume(SRV)as a single-medium while the SRV region itself is described using a double-medium strategy which can account for thefluid exchange between the matrix and the micro-fractures.The shale gas adsorption,desorption,diffusion,gas slippage effect,fracture stress sensitivity,and capillary imbibition have been considered.The shale gas production,pore pressure distribution and water saturation distribution in the reservoir have been simulated.The influences of hydraulic fracture geometry and nonorthogonal hydraulic fractures on gas production have been determined and discussed accordingly.The simulation results show that the daily gas production has an upward and downward trend due to the presence of a large amount of fracturingfluid in the reservoir around the hydraulic fracture.The smaller the angle between the hydraulic fracture and the wellbore,the faster the daily production of shale gas wells decreases,and the lower the cumulative production.Nonplanar fractures can increase the control volume of hydraulic fractures and improve the production of shale gas wells. 展开更多
关键词 Shale gas fracturingfluid backflow the stimulated reservoir volume gas-water two-phase production
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Tumor-infiltrating T-Lymphocyte immunity-related immune tolerance and anti–programmed cell death protein 1/ligand of programmed cell death protein 1 therapy for advanced hepatocellular carcinoma
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作者 Lingzhen Hu Zongren Wang +3 位作者 Yang Liao Xiaomeng Jiang Huojun Lian Zhuoying Lin 《Oncology and Translational Medicine》 CAS 2024年第4期162-170,共9页
Systemic therapy has become the standard treatment for patients with advanced hepatocellular carcinoma(HCC)whose treatment options are limited.However,the long-term patient response to drugs and the survival outcomes ... Systemic therapy has become the standard treatment for patients with advanced hepatocellular carcinoma(HCC)whose treatment options are limited.However,the long-term patient response to drugs and the survival outcomes remain a concern.With increasing exploration of the HCC microenvironment,particularly in terms of T lymphocyte immunity,a new era of immunomolecular targeted therapy,based on molecular signaling,has arrived for advanced HCC.In the study of immune tolerance of the intrinsic HCC microenvironment,we found that multiple immunosuppressive mechanisms and immune checkpoint inhibitors,such as anti–programmed cell death protein 1/ligand of programmed cell death protein 1 therapy,have improved clinical outcomes in some patients with advanced HCC.Furthermore,various combination therapies have been investigated,and HCC types have been categorized into different types based on anti–programmed cell death protein 1(PD-1)/ligand of programmed cell death protein 1(PD-L1)treatment.In this paper,we first discuss the tumor-infiltrating T lymphocyte immunity and immune tolerance of HCC.We then clarify the basic mechanism of anti–PD-1/PD-L1 therapy and discuss the types of HCC based on anti–PD-1/PD-L1 therapy.Thereafter,we explain the relevant studies and mechanisms of combination therapy of anti–PD-1/PD-L1 with antiangiogenesis drugs or multikinase kinase inhibitors,anti–T lymphocyte–related signaling pathways in HCC,and other anti-CD8+T cell immune checkpoints.In this way,this review offers a deeper understanding of anti–PD-1/PD-L1 immunotherapy for advanced HCC,in order to provide better individualized treatments for patients with advanced HCC. 展开更多
关键词 anti–PD-1/PD-L1 treatment Combination therapy Hepatocellular carcinoma Immune tolerance Tumor-infiltrating T lymphocyte immunity
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Antibody Pattern: Correlation of Age and Gender in ANA and Anti-ds-DNA Prevalence
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作者 Usama Ahmed Hijazi Mallick +1 位作者 Amber Khan Muhammad Zubair 《Journal of Clinical and Nursing Research》 2024年第6期373-381,共9页
The study was designed to find the prevalence of ANA antibodies and anti-dsDNA antibodies in samples tested at AFIP Rawalpindi and their correlation with age and gender and to find positive and negative predictive val... The study was designed to find the prevalence of ANA antibodies and anti-dsDNA antibodies in samples tested at AFIP Rawalpindi and their correlation with age and gender and to find positive and negative predictive values of ANA antibodies.For this purpose,twelve thousand nine hundred sixty-seven(12,967)patients were analyzed for ANA with four hundred sixty-eight(468)healthy samples tested as control and four thousand seven hundred three(4,703)patients tested for ds-DNA antibodies.Retrospective data of all samples tested by indirect immunofluorescence(IF)for ANA antibodies and dsDNA antibodies was collected.To address positive and negative predictive values another control group(autoimmunity not suspected)of serum samples was taken from the healthy population.For the first group,age,gender,ANA antibodies and ds-DNA antibodies results(both tests performed by IIF)data was collected from a computer record cell;for the second control group,ANA antibodies were performed by IIF.12,967 and 4,703 samples(Group 1)were tested for ANA antibodies and dsDNA antibodies,respectively,during this period.1,119(9%)and 99(2%)were found positive for ANA antibodies and ds DNA antibodies.Among these positive samples,850(76%)and 73(74%)were females respectively.Gender predisposition towards autoimmunity(ANA)was found significant with a P value of(P=0.001).Relation of age was also found significant with anti-ANA antibodies with a P value of(P=0.001).This study shows a negative correlation between age(P=0.025)and gender(P=0.001)with anti-dsDNA which is also significant.High prevalence was found below the mean age of 38 years(SD±16.635)for ANA antibodies and the mean age of 35 years(SD±15.066)for ds-DNA antibodies.The age of ANA antibodies and dsDNA antibodies positive patients ranged from 1 year old to 98 years old and 2 years old to 95 years old respectively.In the second(autoimmunity-free)control group,a total of 468 samples were tested for ANA antibodies and 9(2%)were found positive.Positive predictive value(PPV)was 8.6%and negative predictive value(NPV)was 98%.ANA is a sensitive test for autoimmunity and it is significantly related to female gender and increasing age.The low prevalence of ANA antibodies among clinically suspected cases suggests that rationalization of test prescriptions is needed.Anti-ds-DNA is also a sensitive test for diagnosis of SLE and it is significantly related to female gender and increasing age. 展开更多
关键词 ANA anti ds-DNA AUTOIMMUNITY SLE Immune fluorescence
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孕早期阴道超声s-Flow检查联合血清ACA及anti-β2GPI评估先兆流产患者不良妊娠结局价值 被引量:6
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作者 耿媛媛 李燕 +1 位作者 郭伟 孙屹梅 《中国计划生育学杂志》 2023年第8期1908-1911,共4页
目的:探讨孕早期行阴道双向能量多勒普技术(s-Flow)联合血清抗心磷脂抗体(ACA)及抗β2-糖蛋白Ⅰ(anti-β2GPI)检查预测先兆流产患者不良妊娠结局价值。方法:收集本院妇产科2018年6月-2020年6月收治的320例先兆流产孕妇临床资料,检测超... 目的:探讨孕早期行阴道双向能量多勒普技术(s-Flow)联合血清抗心磷脂抗体(ACA)及抗β2-糖蛋白Ⅰ(anti-β2GPI)检查预测先兆流产患者不良妊娠结局价值。方法:收集本院妇产科2018年6月-2020年6月收治的320例先兆流产孕妇临床资料,检测超声血流分型、血清ACA、anti-β2GPI水平,根据妊娠结果分为正常组(n=241例)和不良组(n=79例)。采取logistic回归分析影响不良妊娠结局的因素,受试者工作特征(ROC)曲线评估上述指标的预测价值。结果:两组血流信号分级比较有差异(P<0.05),不良组血清ACA、anti-β2GPI水平高于正常组(P<0.05)。logistic回归分析,阴道s-Flow技术血流信号分级、血清ACA、anti-β2GPI均为不良妊娠结局发生的独立危险因素(P<0.05)。评估不良妊娠结局的曲下面积阴道s-Flow技术血流信号分级0.578;血清ACA截断值>3.87 mIU/ml时曲下面积0.787,anti-β2GPI截断值>7.29 U/ml时曲下面积为0.745,以阴道s-Flow技术血流信号分级、ACA、anti-β2GPI联合预测不良妊娠结局的曲下面积0.881,敏感度81.0%、特异度79.3%。结论:孕早期行阴道s-Flow技术联合血清ACA及antiβ2GPI抗体检测对评估妊娠结局有较好效能。 展开更多
关键词 先兆流产 孕早期 阴道s-Flow技术 抗心磷脂抗体、抗β2-糖蛋白Ⅰ 不良妊娠结局 评估
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直播信息特性和产品感知对冲动购买的影响研究——基于Howard-Sheth模型
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作者 刘人铭 《中国商论》 2024年第3期29-32,共4页
基于Howard-Sheth模型,本文从外部信息和感知刺激角度实证探索社交电商直播信息特征和产品感知价值对冲动购买意愿的影响机制,采取便利性抽样收集245份有效问卷,运用AMOS-结构方程模型对效应路径进行实证检验。结果表明:社交电商直播信... 基于Howard-Sheth模型,本文从外部信息和感知刺激角度实证探索社交电商直播信息特征和产品感知价值对冲动购买意愿的影响机制,采取便利性抽样收集245份有效问卷,运用AMOS-结构方程模型对效应路径进行实证检验。结果表明:社交电商直播信息交互性、产品感知享乐价值和感知实用价值对心流体验有显著的促进作用,心流体验进一步影响消费者冲动购买意愿;信息时效性对心流体验的影响不显著。基于此,文章通过将Howard-Sheth模型拓展到社交电商直播场景中,并为社交电商提出几点营销思考进而为电子商务行业理解社交电商消费者行为提供了新视角。 展开更多
关键词 冲动购买 Howard-Sheth模型 信息质量 感知价值 心流体验
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基于特征信息融合预测Anti-CRISPR蛋白
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作者 张迪萌 李凤敏 《内蒙古大学学报(自然科学版)》 CAS 2024年第3期281-291,共11页
CRISPR-Cas系统是一种存在于细菌和古细菌中的获得性免疫系统,作为基因编辑工具在癌症治疗等方面被广泛研究,但CRISPR-Cas基因编辑技术存在基因脱靶效应。研究发现,Anti-CRISPR蛋白是一种可以调节CRISPR-Cas系统功能的蛋白质,在不破坏... CRISPR-Cas系统是一种存在于细菌和古细菌中的获得性免疫系统,作为基因编辑工具在癌症治疗等方面被广泛研究,但CRISPR-Cas基因编辑技术存在基因脱靶效应。研究发现,Anti-CRISPR蛋白是一种可以调节CRISPR-Cas系统功能的蛋白质,在不破坏靶向基因编辑的情况下,可以减少脱靶效应等不良影响,从而提高基因编辑技术的效率和安全性。因此,研究Anti-CRISPR蛋白对于理解CRISPR-Cas系统的功能和细菌-病毒相互作用具有重要意义。本文构建了Anti-CRISPR蛋白数据集,提取氨基酸组分、氨基酸二肽组分、g-gap二肽组成、蛋白质二级结构、平均化学位移和蛋白质骨架6种特征参数,利用支持向量机对Anti-CRISPRs蛋白进行预测,在Jackknife检验下,单特征参数最高预测成功率为93.50%;对维度过高的氨基酸二肽组分和g-gap二肽组成分别进行降维处理,得到g-gap二肽组成在g=3、维数是121维时预测成功率最高,为95.10%,进一步研究发现有16种g-gap二肽组合对应11种氨基酸与Anti-CRISPR蛋白预测相关度较大;最后对特征参数进行融合,融合后最高预测成功率为96.07%。 展开更多
关键词 anti-CRISPR蛋白 特征信息 降维 预测
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基于YOLOv5s-AntiUAV的反无人机目标检测算法研究 被引量:2
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作者 谭亮 赵良军 +1 位作者 郑莉萍 肖波 《电光与控制》 CSCD 北大核心 2024年第5期40-45,107,共7页
随着无人机的应用领域不断拓展,无人机的“黑飞”给公共安全造成严重损害。为解决侵入式无人机小目标在复杂飞行环境下的错检和漏检问题,提出基于YOLOv5s-AntiUAV的反无人机目标检测算法。首先,引入结合深度超参数卷积的Slim-Neck范式,... 随着无人机的应用领域不断拓展,无人机的“黑飞”给公共安全造成严重损害。为解决侵入式无人机小目标在复杂飞行环境下的错检和漏检问题,提出基于YOLOv5s-AntiUAV的反无人机目标检测算法。首先,引入结合深度超参数卷积的Slim-Neck范式,增强算法特征提取能力并保持计算效率。其次,在骨干和颈部网络引入SPD-Conv模块,提高在低分辨率图像中小目标的检测性能。最后,用Alpha-CIoU替换YOLOv5s算法中的CIoU,增强算法泛用性。YOLOv5s-AntiUAV算法与YOLOv5s、SSD和Faster R-CNN算法在数据集Anti-UAV上的对比实验结果表明,改进算法的mAP@0.5值分别增长了1.1、12.1和4.9个百分点,凸显其实用性。由在VisDrone2019数据集上进行的迁移实验显示,相较于YOLOv5s算法,改进算法mAP@0.5值提升了4.5个百分点,表明其相较于原算法具有更强的鲁棒性。 展开更多
关键词 反无人机算法 小目标检测 YOLOv5s 复杂背景 Alpha-CIoU
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Copper Mineralization in the Lower Cambrian Cover of Jbel N’Zourk (Central Anti Atlas, Morocco): Tectonic-Mineralizations Relationships
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作者 Achraf Ait Yazza Ismail Bouskri +2 位作者 Mohamed Raji Faouziya Haissen Noura Zoraa 《Open Journal of Geology》 2023年第11期1195-1219,共25页
The Moroccan Anti-Atlas is a vast geological region composed of a Precambrian basement covered by a late-Neoproterozoic to Paleozoic sedimentary sequences. More than 200 copper occurrences are listed in these sequence... The Moroccan Anti-Atlas is a vast geological region composed of a Precambrian basement covered by a late-Neoproterozoic to Paleozoic sedimentary sequences. More than 200 copper occurrences are listed in these sequences. The copper mineralization of the Jbel N’Zourk (Central Anti-Atlas) is observed into the lower Limestones of the lower Cambrian (Adoudou formation), just above the volcanic formations of the Jbel Boho between Bou Azzer El Graara and Zenaga inliers. The region is by an E-W shortening resulting in an overlapping structure with vergence associated with folds. Generally, the mineralization is hosted along the principal fault of Jbel N’Zourk and sometimes in the anticlines hinges. The petrographic study showed that the mineralization can be observed in several aspects, either in the fractures and veins, in small karsts or rarely disseminated in calcite and dolomite minerals. These observations host new arguments who contribute to a later reconcentration of the copper mineralization of Jbel N’Zourk, trapped on faulted and folded structures attributed to Variscan deformation. 展开更多
关键词 Central anti-Atlas Lower Cambrian Cover Copper Mineralization Structural
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基于显示器安装技术的核电站抗震屏风式OWP盘台的设计
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作者 张伟 《自动化博览》 2024年第5期58-63,共6页
根据操作员在C项目主控室盘台Mock Up验证过程中,针对OWP盘台提出的关于实现显示器密集安装和避免显示器之间缝隙漏光的新要求,本项目研发了抗震屏风式OWP盘台。核电站抗震屏风式OWP盘台利用屏风和显示器支架的相互配合可实现上述新要求... 根据操作员在C项目主控室盘台Mock Up验证过程中,针对OWP盘台提出的关于实现显示器密集安装和避免显示器之间缝隙漏光的新要求,本项目研发了抗震屏风式OWP盘台。核电站抗震屏风式OWP盘台利用屏风和显示器支架的相互配合可实现上述新要求:屏风具有足够高的固有频率和贯穿宽度方向的滑道结构,作为显示器支架载体的同时还可实现显示器支架的左右移动,即实现显示器的左右移动;显示器支架自身可实现显示器前后移动及万向角度调整,且各自由度均可可靠锁紧,二者配合可实现显示器的密集安装要求;屏风作为一道物理屏障可实现避免显示器与显示器之间缝隙漏光的要求。通过验证,核电站抗震屏风式OWP盘台可避免显示器与显示器之间的缝隙漏光,可实现显示器的均匀分布且最小间距可达到10mm,并满足相关核电站的抗震要求。 展开更多
关键词 抗震 owP 显示器 屏风 显示器支架 结构设计
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Antibacterial, Anti-Inflammatory and Antioxidant Activities of an ACAZY Herbal Formula Used in Traditional Medicine to Treat Respiratory Infections
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作者 Mohamed Bonewendé Belemlilga Bagora Bayala +20 位作者 Abdoul Gilchrist Laurent Boly Madinatou Annick Ouédraogo Alida Raissa Boina Boubacar Yaro Florentina Badea Camélia Diguti Moumouni Koala Denise P. Ilboudo Charles Bavouma Sombié Pascal Nadembega Jean-Marie Compaoré Paul Darga Mahoukèdè Théodora Zohoncon Moussa Ouédraogo Aristide Traore Noufou Ouédraogo Florentina Matei Rasmane Semdé Sylvin Ouédraogo Jacques Simporé Innocent Pierre Guissou 《Natural Science》 2024年第9期131-145,共15页
ACAZY is a plant formula used in traditional medicine in Burkina Faso to treat respiratory infections. After phytochemical analysis, this study evaluated extracts’ anti-inflammatory, antioxidant and antibacterial pro... ACAZY is a plant formula used in traditional medicine in Burkina Faso to treat respiratory infections. After phytochemical analysis, this study evaluated extracts’ anti-inflammatory, antioxidant and antibacterial properties from the ACAZY recipe. Three extractions, an aqueous macerate (AM), an aqueous decoction (AD) and an hydroethanolic macerate (HEM) of the ACAZY recipe powder were carried out. Phytochemical screening of the extracts was carried out using high-performance thin-layer chromatography (HPTLC) and the determination of phenolic compounds. The anti-inflammatory potential was assessed in vitro using pro-inflammatory enzyme inhibition tests. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and Ferric-reducing antioxidant power (FRAP) antioxidant properties were also determined. The antibacterial activity was evaluated on Staphylococcus aureus and Streptococcus pneumoniae strains. Phytochemical analysis revealed the presence of flavonoids, saponins, tannins, anthracenosids, sterols and triterpenes in the extracts. The extracts inhibited pro-inflammatory enzymes by more than 40% at only 100 µg/mL. The extracts also showed potent antibacterial activity with a minimum inhibitory concentration 1 mg/mL on Staphylococcus aureus and 2 mg/mL on Streptococcus pneumoniae. The extracts in the ACAZY formula have shown anti-inflammatory and antioxidant properties in vitro. The AD also showed an antibacterial activity. This justifies its use in traditional medicine to treat acute respiratory infections. 展开更多
关键词 ACAZY anti-INFLAMMATORY antiOXIDANT antiBACTERIAL In Vitro
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Safety and in Vivo Anti-Inflammatory Activity of Ethanolic Extract of Ficus umbellata (Vahl.) Leaves
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作者 Atchadé Pascal Tchogou Steven Amour Pyus Tanguy Vignon Chokki +7 位作者 Gbèssohèlè Justin Behanzin Tétédé Rodrigue Christian Konfo Perside Savoeda Félicienne Agbogba Léocardie Akpoli Lamine Baba-Moussa Maximin Senou Alphonse Sezan 《Journal of Biosciences and Medicines》 2024年第3期94-112,共19页
Toxicity is the totality of adverse effects, which can be functional and morphological lesions in a living organism, caused by a substance introduced in relatively high single doses or in small, repeated doses. The ai... Toxicity is the totality of adverse effects, which can be functional and morphological lesions in a living organism, caused by a substance introduced in relatively high single doses or in small, repeated doses. The aim of this study was to assess the OECD-recommended acute oral toxicity and anti-inflammatory activity of ethanolic extract of Ficus umbellata leaves. Animals were given a single oral dose of 1000, 3000 and 5000 mg/Kg body weight (BW) of the extract. For the anti-inflammatory activity test, rats were given the ethanolic extract of F. umbellata leaves at doses of 100, 300 and 500 mg/Kg or aspirin® at a concentration of 100 mg/Kg PC orally, one hour before injection of 0.05 ml of 1% formalin under the plantar fascia of the rat’s right hind paw. Paw volume measurements were taken one, two and three hours after formalin injection, using an electronic caliper. After 14 days of observation, no deaths were observed in treated rats. The LD50 of ethanolic extract of Ficus umbellata leaf powder is greater than 5000 mg/Kg body weight. This extract has no significant effects on hematological parameters and on the main markers of nephrotoxicity and hepatotoxicity for a single dose of less than 5000 mg/Kg PC. It reduces formalin-induced edema. Evaluation of the percentage inhibition showed that the extract had greater anti-inflammatory activity at 3 hours after the start of the experiment. However, better inhibition of inflammatory oedema of the paw of rats treated with 500 mg/Kg was observed at 5 hours after the start of the experiment, with a percentage inhibition of 69.23 ± 1.02, compared with the reference group treated with aspirin® 100 mg/Kg, which showed an inhibition of 63.50 ± 0.98. These results show that F. umbellata leaves possess anti-inflammatory activity, which would justify their use in traditional African medicine to prevent or treat inflammation. 展开更多
关键词 Ficus umbellata TOXICITY anti-INFLAMMATORY EDEMA Inflammation
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轮图中三类特殊子图的anti-Ramsey数
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作者 覃忠美 申悦 刘奋进 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第5期562-567,579,共7页
在边染色图中,如果某个子图的每条边都染不同的颜色,则称该子图是彩虹的。给定图G和H,对图G的一个k边染色若存在最大的正整数R,使得G中不包含彩虹的H作为子图,则将H的anti-Ramsey数记为ar(G,H)。当主图为轮图时,给出了Theta图、星图和... 在边染色图中,如果某个子图的每条边都染不同的颜色,则称该子图是彩虹的。给定图G和H,对图G的一个k边染色若存在最大的正整数R,使得G中不包含彩虹的H作为子图,则将H的anti-Ramsey数记为ar(G,H)。当主图为轮图时,给出了Theta图、星图和双星图anti-Ramsey数的精确值。 展开更多
关键词 轮图 anti-Ramsey数 Theta图 星图 双星图
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