检索结果-南通市图书馆

CF-DAN: Facial-expression recognition based on cross-fusion dual-attention network

在线全文

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第3期10卷 593-608页

作者： fan Zhang Gongguan Chen hua Wang Caiming Zhang Shandong Technology and Business University Shandong 264005China School of Information and Electrical Engineering Ludong UniversityYantai 264025China Shangdong University Shandong 250100China

Recently, facial-expression recognition (FER)has primarily focused on images in the wild, includingfactors such as face occlusion and image blurring, ratherthan laboratory images. Complex field environmentshave introduced new challenges to FER. To addressthese challenges, this study proposes a cross-fusion dualattention network. The network comprises three parts:(1) a cross-fusion grouped dual-attention mechanism torefine local features and obtain global information;(2) aproposed C2 activation function construction method,which is a piecewise cubic polynomial with threedegrees of freedom, requiring less computation withimproved ﬂexibility and recognition abilities, whichcan better address slow running speeds and neuroninactivation problems;and (3) a closed-loop operationbetween the self-attention distillation process andresidual connections to suppress redundant informationand improve the generalization ability of the *** recognition accuracies on the RAF-DB, FERPlus,and AffectNet datasets were 92.78%, 92.02%, and63.58%, respectively. Experiments show that this modelcan provide more effective solutions for FER tasks.

关键词： facial-expression recognition(FER) cubic polynomial activation function dualattention mechanism interactive learning self-attention distillation

Corrosion Behaviour of a Non‑equiatomic CoCrFeNiMo High‑Entropy Alloy in H_(2)S‑Containing and H_(2)S‑Free Environments

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 366-378页

作者： Zhu Wang Guo‑Hui Zhang Yong Yao Xue‑hua fan Jie Jin Lei Zhang Yan‑Xia Du Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China CITIC Pacific Special Steel Group Co. LtdJiangsu 214429China China Petroleum Engineering&Construction Co. Ltd Beijing CompanyBeijing 100085China

The corrosion behaviour of a non-equiatomic CoCrFeNiMo high-entropy alloy(HEA)in H_(2)S-containing and H_(2)S-free environments was studied by electrochemical tests,surface characterization,and solution *** results showed that the HEA exhibited primary and secondary passivation in the H_(2)S-free environment,and the transition was owing to the enhanced dissolution of Fe *** with the primary passive film,the Cr/Fe ratio in the secondary passive film increased at the expense of the selective dissolution of ***,the corrosion resistance of HEA decreased with the applied *** was the most stable element in the film of HEA,regardless of H_(2)*** presence of H_(2)S accelerated the dissolution of all the cationic elements in the HEA.H_(2)S promoted the formation of thicker but less protective surface film and induced the loss of passivity.

关键词： High-entropy alloy(HEA) Corrosion H_(2)S Secondary passivation X-ray photoelectron spectroscopy(XPS) Induced coupled plasma(ICP)

Effect of Partially Substituting Ca with Mischmetal on the Microstructure and Mechanical Properties of Extruded Mg-Al-Ca-Mn-Based Alloys

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 205-217页

作者： Chao Xu Taiki Nakata Guo-hua fan Kosuke Yamanaka Guang-Ze Tang Lin Geng Shigeharu Kamado School of Materials Science and Engineering Harbin Institute of Technology Department of Mechanical Engineering Nagaoka University of Technology

Mg-2Al-1.2Ca-0.2Mn(at%)-based alloys with Ce-rich mischmetal(MM) substitution of 0–0.6 at% for Ca were hot extruded at 400 °C. The effect of MM substitution on the microstructure and mechanical properties of the extruded alloys was investigated. The as-cast Mg-2Al-1.2Ca-0.2Mn alloy is mainly composed of a-Mg, Mg_2Ca and(Mg,Al)_2Ca phases and Al_8Mn_5 precipitates, whereas the substitution of MM brings about the formation of Al_(11)MM_3, Al_2MM phases and Al_(10)MM_2Mn_7 particles with the absence of (Mg,Al)_2Ca phase. The volume fraction of MM-containing phases increases with increasing MM contents. All of the extruded alloys exhibit bimodal microstructure comprising fine dynamically recrystallized grains with almost random orientation and coarse deformed grains with strong basal texture. Dense nanosized planar Al_2Ca and spherical Al–Mn phases precipitate inside the deformed grains. High tensile yield strengths of~ 350 MPa and moderate elongations to failure of >12% are obtained in all extruded alloys; the MM substitution induces negligible difference in the tensile properties at ambient temperature, while the highest MM substitution improves the strength at 180 °C due to the better thermal stability of the fragmented MM-containing phases.

关键词： Magnesium alloys Extrusion Microstructures Precipitation Mechanical properties

Electromagnetic attenuation property of multiphase Fe–Fe_3O_4–Al_2O_3 cermets near percolation threshold

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2017年第1期36卷 42-45页

作者： Kai Sun Run-hua fan Zi-Dong Zhang Ke-Lan Yan Xi-hua Zhang Chuan-Bing Cheng Min Chen Pei-Tao Xie Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Shandong University Jinan 250061China

Cermets are widely applied as attenuating materials due to high electromagnetic loss and better mechanical properties. In this paper, multiphase cermets composed of iron, iron oxide and alumina were successfully prepared by a two-step in situ synthesis process,which includes pressureless sintering and a selective reduction in hydrogen atmosphere. The phase composition and microstructure of cermets were analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM), respectively. It is shown that nanosized cuboid Fe particles and octahedral FeOparticles are distributed in alumina matrix. The permittivity and permeability of composites were tested with radio frequency impedance analyzer(0.01–1.00 GHz). The results show that permittivity presents obvious frequency dispersion. Furthermore,dielectric constants of multiphase cermets get enlarged due to the enhancement of interfacial polarization. On the other hand, there is a magnetic loss peak in permeability spectra,which indicates typical relaxation behavior. It is possible to achieve better electromagnetic attenuation property by adjusting process parameters.

关键词： Cermets Attenuating materials Percolative phenomenon Microwave absorption Metamaterials

Exosomal miR-23b from bone marrow mesenchymal stem cells alleviates oxidative stress and pyroptosis after intracerebral hemorrhage

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第3期18卷 560-567页

作者： Liu-Ting Hu Bing-Yang Wang Yu-hua fan Zhi-Yi He Wen-Xu Zheng Department of Neurology The First Affiliated HospitalSun Yat-Sen UniversityGuangzhouGuangdong ProvinceChina Department of Neurology The First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Geriatric Department of Dalian Friendship Hospital DalianLiaoning ProvinceChina

Our previous studies showed that miR-23b was downregulated in patients with intracerebral hemorrhage(ICH). This indicates that miR-23b may be closely related to the patho-physiological mechanism of ICH, but this hypothesis lacks direct evidence. In this study, we established rat models of ICH by injecting collagenase Ⅶ into the right basal ganglia and treating them with an injection of bone marrow mesenchymal stem cell(BMSC)-derived exosomal miR-23b via the tail vein. We found that edema in the rat brain was markedly reduced and rat behaviors were improved after BMSC exosomal miR-23b injection compared with those in the ICH groups. Additionally, exosomal miR-23b was transported to the microglia/macrophages, thereby reducing oxidative stress and pyroptosis after ICH. We also used hemin to mimic ICH conditions in vitro. We found that phosphatase and tensin homolog deleted on chromosome 10(PTEN) was the downstream target gene of miR-23b, and exosomal miR-23b exhibited antioxidant effects by regulating the PTEN/Nrf2 pathway. Moreover, miR-23b reduced PTEN binding to NOD-like receptor family pyrin domain containing 3(NLRP3) and NLRP3 inflammasome activation, thereby decreasing the NLRP3-dependent pyroptosis level. These findings suggest that BMSC-derived exosomal miR-23b exhibits antioxidant effects through inhibiting PTEN and alleviating NLRP3 inflammasome-mediated pyroptosis, thereby promoting neurologic function recovery in rats with ICH.

关键词： bone marrow mesenchymal stem cells exosomal miRNAs intracerebral hemorrhage miR-23b neuroinflammation NLRP3 inflammasome Nrf2 oxidative stress PTEN pyroptosis

Chaihu-Shugan-San exerts an antidepressive effect by downregulating miR-124 and releasing inhibition of the MAPK14 and Gria3 signaling pathways

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2018年第5期13卷 837-845页

作者： Qiong Liu Ning-Ning Sun Zheng-Zhi Wu Da-hua fan Mei-Qun Cao Department of Cardiovascular Medicine Xiang Ya Hospital of Central South University Changsha Hunan Province China Shenzhen Institute of Geriatrics Shenzhen Second People's Hospital The First Affiliated Hospital of Shenzhen University Shenzhen Guangdong Province China The Eighth Affiliated Hospital of Sun Yat-sen University Shenzhen Guangdong Province China Chinese and Wsetern Integrative Medicine Shcool of Medicine Jinan University Guangzhou Guangdong Province China.

Dysregulation of mi R-124 has been reported to be involved in the pathophysiology of depression. Chaihu-Shugan-San, a traditional Chinese medicine, has antidepressive activity; however, the underlying mechanisms remain unclear. In this study, to generate a rodent model of depression, rats were subjected to a combination of solitary confinement and chronic unpredictable mild stress for 28 days. Rats were intragastrically administered Chaihu-Shugan-San（2.835 m L/kg/d） for 4 weeks, once a day. Real-time reverse-transcription quantitative polymerase chain reaction, mi RNA microarray, western blot assay and transmission electron microscopy demonstrated that ChaihuShugan-San downregulated mi R-124 expression and upregulated the m RNA and protein levels of mitogen-activated protein kinase 14（MAPK14） and glutamate receptor subunit 3（Gria3）. Chaihu-Shugan-San also promoted synapse formation in the hippocampus. The open field test, sucrose consumption test and forced swimming test were used to assess depression-like behavior. After intragastric administration of Chaihu-Shugan-San, sucrose consumption increased, while the depressive behaviors were substantially reduced. Together, these findings suggest that Chaihu-Shugan-San exerts an antidepressant-like effect by downregulating mi R-124 expression and by releasing the inhibition of the MAPK14 and Gria3 signaling pathways.

关键词： nerve regeneration traditional Chinese medicine Chaihu-Shugan-San depression open-field test sucrose consumption test forced swimming test miR-124 neural plasticity MAPK14 Gria3 neural regeneration

Asymmetric Hydrogenation of Bis(quinolin-2-yl)methanes:A Direct Access to Chiral 1,3-Diamines

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2018年第12期36卷 1169-1173页

作者： Bin Li Cong Xu Yan-Mei He Guo-Jun Deng Qing-hua fan Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of Sciences [CAS) and University of Chinese Academy of SciencesBeijing 100190China Key Laboratory of Environmentally Friendly Chemistry of the Ministry of Education College of ChemistryXiangtan UniversityXiangtanHunan 411105China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300071China

The asymmetric hydrogenation of bis(quinolin‐2‐yl)methanes was described, using chiral cationic ruthenium/monosulfonated diamine complexes to afford chiral bis(tetrahydroquinolin‐2‐yl)methanes in high yield with excellent enantioselectivity and diastereoselectivity. The subsequent transformation of these 1,3‐diamines to a new class of chiral 6‐membered N‐heterocyclic carbenes was also developed, which is important but difficult to access. The first asymmetric hydrogenation of bis(quinolin‐2‐yl)methanes using chiral cationic ruthenium diamine catalysts was developed with up to > 20 : 1 dr and > 99% ee. This new protocol provides a practical and facile approach to not only chiral 1,3‐diamines but also a novel class of 6‐membered chiral NHC ligands. [ABSTRACT FROM AUTHOR]

关键词： asymmetric catalysis chiral 1,3‐diamines heterocycles hydrogenation ruthenium

机器人辅助全膝关节置换过程中创伤效应的利弊

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国组织工程研究 2024年第21期28卷 3413-3417页

作者：杨永泽程晴灏张安任杨鑫张壮壮樊华张福康郭洪章甘肃中医药大学第一临床医学院甘肃省兰州市780000 甘肃省人民医院骨科四病区甘肃省兰州市780000

背景:应用机器人辅助技术进行全膝关节置换是目前的研究热点之一。从20世纪80年代起,国外将机器人辅助技术引入全膝关节置换术中,以实现精准截骨和恢复良好的下肢力线。经过几十年的使用,机器人不断更新迭代性能更加优越,但因其增加围... 详细信息

背景:应用机器人辅助技术进行全膝关节置换是目前的研究热点之一。从20世纪80年代起,国外将机器人辅助技术引入全膝关节置换术中,以实现精准截骨和恢复良好的下肢力线。经过几十年的使用,机器人不断更新迭代性能更加优越,但因其增加围术期时间和手术创伤而受到批评。目的:总结现今骨科手术机器人在全膝关节置换过程中创伤方面的优缺点。方法:检索PubMed数据库和中国知网收录的有关分析手术机器人辅助全膝关节置换手术创伤优势及不足的文章,英文检索词为“arthroplasty,replacement,knee,knee replacement arthroplasty,procedure,robotic surgical,total knee arthroplasty,arthroplasty,replacement,knee,robotic-assisted”,中文检索词为“机器人辅助,机械臂,膝骨关节炎,关节炎”。根据纳入与排除标准对所有文章进行初筛后,保留质量和相关性较高的62篇文献进行综述。结果与结论:①手术机器人辅助全膝关节置换并未增加患者手术创伤程度,并且表现出比传统全膝关节置换更低的创伤效应;②手术机器人辅助全膝关节置换具有准确辅助截骨、个体化置入假体、更好地保护膝关节周围软组织、减少镇痛药物使用、降低术后炎症指标变化、缩短住院时间等降低创伤方面的优势,但也存在手术耗时延长、并发症增加、医疗成本提高等不足;③提示初步临床应用研究显示手术机器人辅助全膝关节置换可以降低手术创伤,但需要警惕潜在风险,同时与传统全膝关节置换相比其确切优势尚待大样本随机对照研究和长期随访来验证。

关键词：机器人辅助全膝关节置换传统术式膝骨关节炎创伤利弊

Corrosion Protection of AA2024-T3 by Cerium Malate and Cerium Malate-Doped Sol-Gel Coatings

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 913-924页

作者： Tian-Hui Hu Hong-Wei Shi Tao Wei Shi-hua fan Fu-Chun Liu En-Hou Han Department of Chemistry Northeastern University Shenyang 110819 China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Cerium malate (CeMal) was tested as a corrosion inhibitor for AA2024-T3 in this work. Corrosion inhibition on bare AA2024-T3 indicated that the inhibiting effect was a result of the synergistic effect of cerium cations and maleic anions. The corrosion of AA2024-T3 was stagnated by greatly reducing the corrosion current when CeMal was present in NaCl solutions. CeMal was adsorbed on the surface of AA2024-T3 forming a protective film in the initial stage. Then, cerium cations transformed to cerium oxide/hydroxides, precipitating on the cathode sites to inhibit the further corrosion. The electrochemical impedance spectra results of the sol-gel coatings proved that CeMal was an effective corrosion inhibitor in the sol-gel coatings to provide corrosion protection for AA2024-T3.

关键词： AA2024-T3 Corrosion inhibitor Sol-gel coatings Scanning vibrating electrode technique (SVET)-Electrochemical impedance spectroscopy (EIS)