检索结果-南通市图书馆

Tailoring electron vortex beams with customizable intensity patterns by electron diffraction holography

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Advances 2024年第2期7卷 14-21页

作者： Pengcheng Huo Ruixuan Yu Mingze Liu Hui Zhang yan-qing Lu Ting Xu National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China College of Engineering and Applied Sciences Key Laboratory of Intelligent Optical Sensing and Manipulation and Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

An electron vortex beam(EVB) carrying orbital angular momentum(OAM) plays a key role in a series of fundamental scientific researches, such as chiral energy-loss spectroscopy and magnetic dichroism spectroscopy. So far, almost all the experimentally created EVBs manifest isotropic doughnut intensity patterns. Here, based on the correlation between local divergence angle of electron beam and phase gradient along azimuthal direction, we show that free electrons can be tailored to EVBs with customizable intensity patterns independent of the carried OAM. As proof-of-concept, by using computer generated hologram and designing phase masks to shape the incident free electrons in the transmission electron microscope, three structured EVBs carrying identical OAM are tailored to exhibit completely different intensity patterns. Furthermore, through the modal decomposition, we quantitatively investigate their OAM spectral distributions and reveal that structured EVBs present a superposition of a series of different eigenstates induced by the locally varied geometries. These results not only generalize the concept of EVB, but also demonstrate an extra highly controllable degree of freedom for electron beam manipulation in addition to OAM.

关键词： electron vortex beam orbital angular momentum diffraction holography

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第4期31卷 894-908页

作者： yan-li Xin Zhi-ying Gao Bo Tian qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product quality.Macroscopic instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction coefficient.However,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is applied.Subsequently,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling mill.On one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is determined.Furthermore,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Alzheimer’s disease early diagnostic and staging biomarkers revealed by large-scale cerebrospinal fluid and serum proteomic profiling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Innovation 2024年第1期5卷 118-126页

作者： qing-qing Tao Xue Cai yan-yan Xue Weigang Ge Liang Yue Xiao-yan Li Rong-Rong Lin Guo-Ping Peng Wenhao Jiang Sainan Li Kun-Mu Zheng Bin Jiang Jian-Ping Jia Tiannan Guo Zhi-Ying Wu Department of Neurology and Research Center of Neurology in the Second Affiliated Hospital and Key Laboratory of Medical Neurobiology of Zhejiang Province Zhejiang University School of MedicineHangzhou 310009China Liangzhu Laboratory Zhejiang UniversityHangzhou 311100China Westlake Laboratory of Life Sciences and Biomedicine Key Laboratory of Structural Biology of Zhejiang ProvinceSchool of Life SciencesWestlake UniversityHangzhou 310024China Institute of Basic Medical Sciences Westlake Institute for Advanced StudyHangzho 310024China Department of Neurology First Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Neurology First Affiliated HospitalSchool of MedicineXiamen UniversityXiamen 361009China Innovation Center for Neurological Disorders and Department of Neurology Xuanwu HospitalCapital Medical UniversityNational Clinical Research Center for Geriatric DiseasesBeijing 100053China MOE Frontier Science Center for Brain Science and Brain-machine Integration School of Brain Science and Brain MedicineZhejiang UniversityHangzhou 310058China CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China

Amyloid-b,tau pathology,and biomarkers of neurodegeneration make up the core diagnostic biomarkers of Alzheimer disease(AD).However,these proteins represent only a fraction of the complex biological processes underlying AD,and individuals with other brain diseases in which AD pathology is a comorbidity also test positive for these diagnostic biomarkers.More ADspecific early diagnostic and disease staging biomarkers are needed.In this study,we performed tandem mass tag proteomic analysis of paired cerebrospinal fluid(CSF)and serum samples in a discovery cohort comprising 98 participants.Candidate biomarkers were validated by parallel reaction monitoring–based targeted proteomic assays in an independent multicenter cohort comprising 288 participants.We quantified 3,238 CSF and 1,702 serum proteins in the discovery cohort,identifying 171 and 860 CSF proteins and 37 and 323 serum proteins as potential early diagnostic and staging biomarkers,respectively.In the validation cohort,58 and 21 CSF proteins,as well as 12 and 18 serum proteins,were verified as early diagnostic and staging biomarkers,respectively.Separate 19-protein CSF and an 8-protein serum biomarker panels were built by machine learning to accurately classify mild cognitive impairment(MCI)due to AD from normal cognition with areas under the curve of 0.984 and 0.881,respectively.The 19-protein CSF biomarker panel also effectively discriminated patients with MCI due to AD from patients with other neurodegenerative diseases.Moreover,we identified 21 CSF and 18 serum stage-associated proteins re-flecting AD stages.Our findings provide a foundation for developing bloodbased tests for AD screening and staging in clinical practice.

关键词： cerebrospinal Alzheimer fluid

Wear-resistant Ag-MAX phase 3D interpenetrating-phase composites:Processing,structure,and properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第2期17卷 806-819页

作者： Yu Guo Xi Xie Zengqian Liu Longchao Zhuo Jian Zhang Shaogang Wang Qiqiang duan qing Jia Dake Xu Weihai Xue Deli duan Filippo Berto Zhefeng Zhang Rui yang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Chemical Engineering Materials and EnvironmentSapienza University of RomeRoma 00185Italy

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic instruments.The MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact materials.The biological materials evolved in nature generally exhibit three-dimensional(3D)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact materials.Here,a series of bi-continuous Ag-Ti_(3)SiC_(2) MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3D interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3)SiC_(2) scaffolds.The mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural dimensions.The composites exhibited a good combination of properties with high hardness over 2.3 GPa,high flexural strength exceeding 530 MPa,decent fracture toughness over 10 MPa·m^(1/2),and good wear resistance with low wear rate at an order of 10^(-5)mm^(3)/(N·m),which were much superior compared to the counterparts made by powder metallurgy methods.In particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic contents.The good combination of properties along with the facile processing route makes the Ag-Ti_(3)SiC_(2)3D interpenetrating-phase composites appealing for electrical contact applications.

关键词： three-dimensional(3D)interpenetrating-phase architecture Ag-MAX(M=early transition metal A=element from III or IV main groups and X=carbon or/and nitrogen)phase composites melt infiltration electrical contact materials mechanical

SLC6A14 promotes ulcerative colitis progression by facilitating NLRP3 inflammasome-mediated pyroptosis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第3期30卷 252-267页

作者： qing Gu Huan Xia Yue-Qiong Song Jun duan Yun Chen You Zhang He-Ping Chen Li Zhang Department of Elderly Digestive Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and TechnologyChengdu 610072Sichuan ProvinceChina Geriatrics Research Institute Sichuan Provincial People’s HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Ulcerative colitis(UC)is an inflammatory condition with frequent relapse and recurrence.Evidence suggests the involvement of SLC6A14 in UC pathogenesis,but the central regulator remains unknown.AIM To explore the role of SLC6A14 in UC-associated pyroptosis.METHODS Quantitative real-time polymerase chain reaction(qRT-PCR),immunoblotting,and immunohistochemical were used to assess SLC6A14 in human UC tissues.Lipopolysaccharide(LPS)was used to induce inflammation in FHC and NCM460 cells and model enteritis,and SLC6A14 levels were assessed.Pyroptosis markers were quantified using enzyme-linked immunosorbent assay,Western blotting,and qRT-PCR,and EdU incubation,CCK-8 assays and flow cytometry were used to examine proliferation and apoptosis.Mouse models of UC were used for verification.RESULTS SLC6A14 was increased and correlated with NLRP3 in UC tissues.LPS-induced FHC and NCM460 cells showed increased SLC6A14 levels.Reducing SLC6A14 increased cell proliferation and suppressed apoptosis.Reducing SLC6A14 decreased pyroptosis-associated proteins(ASC,IL-1β,IL-18,NLRP3).NLRP3 overexpression counteracted the effects of sh-SLC6A14 on LPS-induced FHC and NCM460 cell pyroptosis.SLC6A14 improved the mucosa in mice with dextran sulfate sodium-induced colitis.CONCLUSION SLC6A14 promotes UC pyroptosis by regulating NLRP3,suggesting the therapeutic potential of modulating the SLC6A14/NLRP3 axis.

关键词： Ulcerative colitis SLC6A1 NLRP3 Pyroptosis Inflammasome

Association between childhood obesity and gut microbiota:16S rRNA gene sequencing-based cohort study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第16期30卷 2249-2257页

作者： Xu-Ming Li qing Lv Ya-Jun Chen Lu-Biao yan Xin Xiong Laboratory Department Nanjing Medical University Affiliated Obstetrics and Gynecology Hospital(Nanjing Maternal and Child Health Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Shenzhen University General HospitalShenzhen 518055Guangdong ProvinceChina Department of Inspection Division Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Neonatology Chenzhou First People’s HospitalChenzhou 423000Hunan ProvinceChina

BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevention strategies for childhood obesity.Thirty normal-weight and thirty age-and sex-matched obese children were included.Questionnaires and body measurements were collected,and fecal samples underwent 16S rDNA sequencing.Significant differences in body mass index(BMI)and body-fat percentage were observed between the groups.Analysis of gut microbiota diversity revealed lowerα-diversity in obese children.Differences in gut microbiota composition were found between the two groups.Prevotella and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control group.AIM To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood obesity.METHODS Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,respectively.Basic information was collected through questionnaires and body measurements were obtained from both obese and normal-weight children.Fecal samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity analysis.RESULTS Significant differences in BMI and body-fat percentage were observed between the two groups.The Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson indices.Kruskal-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggesting substantial disparities in both the species

关键词： Childhood obesity Gut microbiota 16S rDNA sequencing Diversity analysis Genus identification Body mass index

Myosteatosis is associated with coronary artery calcification in patients with type 2 diabetes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Diabetes 2024年第3期15卷 429-439页

作者： Fu-Peng Liu Mu-Jie Guo qing yang yan-Ying Li yan-Gang Wang Mei Zhang The Affiliated Hospital of Medical College qingdao University Qingdao UniversityQingdao 266071Shandong ProvinceChina Department of Endocrinology The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Medical Imaging The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Clinical Nutrition The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Endocrinology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND Myosteatosis,rather than low muscle mass,is the primary etiologic factor of sarcopenia in patients with type 2 diabetes mellitus(T2DM).Myosteatosis may lead to a series of metabolic dysfunctions,such as insulin resistance,systematic inflammation,and oxidative stress,and all these dysfunctions are closely associated with the acceleration of T2DM and atherosclerosis.AIM To investigate the association between myosteatosis and coronary artery calcification(CAC)in patients with T2DM.METHODS Patients with T2DM,who had not experienced major cardiovascular events and had undergone both abdominal and thoracic computed tomography(CT)scans,were included.The mean skeletal muscle attenuation was assessed using abdominal CT images at the L3 level.The CAC score was determined from thoracic CT images using the Agatston scoring method.Myosteatosis was diagnosed according to Martin’s criteria.Severe CAC(SCAC)was defined when the CAC score exceeded 300.Logistic regression and decision tree analyses were performed.RESULTS A total of 652 patients with T2DM were enrolled.Among them,167(25.6%)patients had SCAC.Logistic regression analysis demonstrated that myosteatosis,age,duration of diabetes,cigarette smoking,and alcohol consumption were independent risk factors of SCAC.Myosteatosis was significantly associated with an increased risk of SCAC(OR=2.381,P=0.003).The association between myosteatosis and SCAC was significant in the younger patients(OR=2.672,95%CI:1.477-4.834,P=0.002),but not the older patients(OR=1.456,95%CI:0.863-2.455,P=0.188),and was more prominent in the population with lower risks of atherosclerosis.The decision tree analyses prioritized older age as the primary variable for SCAC.In older patients,cigarette smoking was the main contributing factor for SCAC,while in younger patients,it was myosteatosis.CONCLUSION Myosteatosis is a novel risk factor for atherosclerosis in patients with T2DM,especially in the population with younger ages and fewer traditional risk factors.

关键词： Type 2 diabetes Myosteatosis Muscle quality Coronary artery calcification Atherosclerosis Cardiovascular diseases

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-Wen Sun Fu-Shan Wang yan Gao Fu-qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo Chen Xiaoping Pang qing Ji Zhongnan yan Zeyu Liang Chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea ice.Whether Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further investigation.This paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter data.We first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar images.Second,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface heights.We then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium equation.Finally,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice thickness.The results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 m.The proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters