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Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： xue-qin Ji xiao-song Zhang chen-jun Yang xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise underwater.The blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance flow.In the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence model.The measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip geometry.The strong fluctuations of duct-surface pressures are caused by intensive tip separation vortices.The duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

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Identification of two compound heterozygous GNRHR mutations in two siblings with congenital hypogonadotropic hypogonadism

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Asian Journal of Andrology 2024年第1期26卷 120-122页

作者： xiao-Bin Wang Ping chen xue-Er Yu Zu-Liang Yao Ting-Chao Guo Bo-chen Pan Center for Reproductive Medicine Department of Obstetrics and GynecologyShengjing Hospital of China Medical UniversityShenyang 110004China NuProbe Shanghai 200433China Urology Surgery of The Affiliated Reproductive Hospital of China Medical University and Liaoning Key Laboratory of Reproductive Health Liaoning Research Institute of Family Planning(The Affiliated Reproductive Hospital of China Medical University)Shenyang 110031China NHC Key Laboratory of Reproductive Health and Medical Genetics China Medical UniversityShenyang 110122China

DearEditor,Congenital hypogonadotropic hypogonadism(CHH)is a rare genetic disease characterized by gonadotropin-releasing hormone(GnRH)deficiency or insufficiency and normal hypothalamic-pituitary structures,resulting in defective sexual maturation or/and infertility.!CHH presents as a variety of nonreproductive phenotypes,such as renal hypoplasia,dental hypoplasia,or oculomotor abnormalities.

关键词： pogon compound ism

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Risk factors,prognostic factors,and nomograms for distant metastasis in patients with diagnosed duodenal cancer:A population-based study

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1384-1420页

作者： Jia-Rong Shang chen-Yi Xu xiao-xue Zhai Zhe Xu Jun Qian Department of Oncology Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Proctology Nanjing Hospital of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Digestive Cancer Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina

BACKGROUND Duodenal cancer is one of the most common subtypes of small intestinal cancer,and distant metastasis(DM)in this type of cancer still leads to poor prognosis.Although nomograms have recently been used in tumor areas,no studies have focused on the diagnostic and prognostic evaluation of DM in patients with primary duodenal cancer.AIM To develop and evaluate nomograms for predicting the risk of DM and person-alized prognosis in patients with duodenal cancer.METHODS Data on duodenal cancer patients diagnosed between 2010 and 2019 were extracted from the Surveillance,Epidemiology,and End Results database.Univariate and multivariate logistic regression analyses were used to identify independent risk factors for DM in patients with duodenal cancer,and univariate and multivariate Cox proportional hazards regression analyses were used to determine independent prognostic factors in duodenal cancer patients with DM.Two novel nomograms were established,and the results were evaluated by receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS A total of 2603 patients with duodenal cancer were included,of whom 457 cases(17.56%)had DM at the time of diagnosis.Logistic analysis revealed independent risk factors for DM in duodenal cancer patients,including gender,grade,tumor size,T stage,and N stage(P<0.05).Univariate and multivariate COX analyses further identified independent prognostic factors for duodenal cancer patients with DM,including age,histological type,T stage,tumor grade,tumor size,bone metastasis,chemotherapy,and surgery(P<0.05).The accuracy of the nomograms was validated in the training set,validation set,and expanded testing set using ROC curves,calibration curves,and DCA curves.The results of Kaplan-Meier survival curves(P<0.001)indicated that both nomograms accurately predicted the occurrence and prognosis of DM in patients with duodenal cancer.CONCLUSION The two nomograms are expected as effective tools for predicting DM risk in duodenal cancer patients

关键词： Duodenal cancer Distant metastasis Nomogram Risk factors Prognostic factors

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Comprehensive analysis and mitigation strategies for safety issues of sodium-ion batteries

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Rare Metals 2024年第4期43卷 1343-1349页

作者： Tao Wei xiao-Ling Xian Shi-xue Dou Wei chen Shu-Lei Chou Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou University Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou University Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation Campus

Sodium-ion batteries show great potential as an alternative energy storage system,but safety concerns remain a major hurdle to their mass adoption.This paper analyzes the key factors and mechanisms leading to safety issues,including thermal runaway,sodium dendrite,internal short circuits,and gas release.Several promising solutions are proposed,such as high-safety electrode materials in the cathode and anode,high-safety electrolytes,and external battery management systems.Here in also we emphasize the importance of selecting appropriate analysis methods and developing reliable failure models while suggesting advanced machine learning tools for analysis.With a comprehensive approach,this study offers valuable recommendations to optimize materials and solutions for improving the safety of sodium-ion batteries.

关键词： Sodium-ion batteries Safety issues Thermal runaway Sodium dendrites

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Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong Duan Wei xue Jun Huang xiao Zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much attention.Conventional classification algorithms are susceptible to data skew to favor majority samples and ignore minority samples.Majority weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority data.To this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these problems.Firstly,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority sample.Note that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate samples.Finally,data cleaning is performed on the processed data to further eliminate class overlap.Experiments on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering

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Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： chen-chen Zhang Sheng Wei Li-Xian Sun Yi-Fang Ouyang Fen Xu Hai-Liang Chu Hong-GePan Li-Xin chen xue-Zhang xiao School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of Materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel cells.However,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent methods.The prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 mA·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C catalyst.Additionally,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),respectively.The outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active sites.The N dope d carbon framework improves the electronic properties and conductivity.Moreover,the strong interaction of Ru and CoP nanoparticles also boosts the HER process.These results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

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Construction of electron rich Fe active sites by FeCu alloy anchoring on carbon nitride for photocatalytic nitrogen reduction

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Rare Metals 2024年第4期43卷 1570-1579页

作者： Gang Dong Cong Huang Fei-Yang chen xue-Qin Liu Zhen Li xiao-Li Su Tao Zeng Yun-Xia chen Yi-Huang chen Yang Wang School of Materials Science and Engineering Jingdezhen Ceramic University Faculty of Materials Science and Chemistry China University of Geosciences College of Chemistry and Materials Engineering Wenzhou University

Given the clean and inexhaustible solar energy from solar light,photocatalytic ammonia synthesis is extremely appealing.However,high electron-hole recombination rates and insufficient active sites severely limited N2 photoreaction reduction.Herein,we designed and fabricated FeCu alloy nanoparticles anchored on carbon nitride nanosheets with excellent photocatalyt ic ammonia synthesis performance.As a coupler between Fe and carbon nitride,Cu promotes the separation of photogenerated charge carriers in carbon nitride under solar light irradiation,and renters the semiconductor a forceful electron donor for the Fe active sites.The accumulated electrons at Fe sites furtherly facilitated the adsorption and activation of the molecular nitrogen.Besides,the uniform dispersed FeCu alloy nanoparticles were on carbon nitride nanosheets enhanced the stability of photocataly tic nitrogen reduction reaction,making the artificial photocataly tic ammonia synthesis more sustainable for application.This work highlights that a direct electron transfer channel can be used to regulate the photochemical nitrogen fixation network.

关键词： Photocatalytic N 2 fixation Carbon nitride FeCu alloy Active sites Hydrogenation pathway

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Isotopic characteristics and source analysis of atmospheric ammonia during agricultural periods in the Xichuan area of the Danjiangkou Reservoir

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Journal of Environmental Sciences 2024年第2期136卷 460-469页

作者： xiaoshu chen Tongqian Zhao Chunyan xiao xiaoming Guo Feihong chen Institute of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000China

Nitrogen deposition is an important means of exogenous nitrogen input in reservoir water.Agricultural activities around the reservoir lead to a sharp increase in the concentration of ammonia in the atmosphere,which poses a threat to the reservoir water body.Clarifying the contribution of agricultural ammonia release to atmospheric NH_(x)(gaseous NH_(3)and particulate NH_(4)^(+)),in the reservoir area can provide a theoretical foundation for local reactive nitrogen control.We collected atmospheric NH_(3)and NH_(4)^(+)samples during the agricultural periods and analyzed the isotopic characteristics of atmospheric NH_(x)and the contribution rates of different ammonia sources in the Xichuan area of the Danjiangkou Reservoir.The results showed that the initialδ~(15)N values of NH_(3)(-30.0‰to–7.2‰)and particulate NH_(4)^(+)(–33‰to+4.9‰for finer and coarser particles,respectively)are different,and their contribution ratios from dissimilar ammonia sources are also different,among which NH_(4)^(+)is more susceptible to meteorological factors.However,since the atmospheric NH_(x)in the Xichuan area is mainly gaseous NH_(3),the final sources of atmospheric ammonia nitrogen source depend on gaseous NH_(3).Agricultural sources(59%-74%)were the main NH_(3)sources in this area.Among them,the fertilizer use emission was dominant;it had the highest contribution rate in summer during the agricultural period and a more prominent impact in areas with less human interference.Reasonable regulation of the application of high-ammonia releasing fertilizer,especially during the agricultural period in summer,is an effective way to reduce the threat of atmospheric ammonia to water health.

关键词： Danjiangkou reservoir Atmospheric ammonia nitrogen Isotope Ammonia source analysis Agricultural sources

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Lignin-reinforced PVDF electrolyte for dendrite-free quasi-solid-state Li metal battery

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Rare Metals 2024年第3期43卷 1006-1016页

作者： Xin-Yang chen xue-Jie Gao Han-Yan Wu Yu-Long Liu xiao-Fei Yang Run-Cang Sun Center for Lignocellulosic Chemistry and Biomaterials College of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian116034China Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China School of Chemistry Northeast Normal UniversityChangchun130024China

Quasi-solid-state lithium metal batteries(QSSLMBs)assembled with polyvinylidene fluoride(PVDF)are a promising class of next-generation rechargeable batteries due to their safety,high energy density,and superior interfacial properties.However,PVDF has a series of inherent drawbacks such as low ionic conductivity,ease of crystallization,and hydrophobic character that leading to poor cell properties.To tackle these issues,a lignin-reinforced PVDF electrolyte is proposed in this work to solve these drawbacks of PVDF and enhance the comprehensive performance of QSSBs.The lithophilic polar groups of lignin can promote uniform deposition of Li on the electrodes.Cooperating with the improved mechanical properties can efficiently prevent Li dendrites penetration through the separator.In addition,more active sites provided by lignin can also enhance Li^(+)transport and lead to a faster electrochemical reaction kinetic.Benefitting from the ingenious design,Li symmetric cells with 5%lignin-PVDF quasi-solid-state electrolyte can operate for 900 h at a high current density/capacity of 5 mA·cm^(-2)/5 mAh·cm^(-2),while shortcircuiting occurs after 56 h for the counterpart(pure PVDF).Moreover,a full cell of Li/5%lignin-PVDF/LFP cell demonstrates a high capacity of 96.2 mAh·g^(-1)after 2000 cycles at 10 C.This work is expected to open up promising opportunities to develop other high-energy/power-density QSSLMBs.

关键词： Quasi-solid-state electrolyte Lignin PVDF Dendrite-free Li metal battery

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Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443

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Chinese Journal of Integrative Medicine 2024年第3期30卷 213-221页

作者： ZHANG Yue xiao Yan-wei MA Jing-xin WANG Ao-xue Department of Dermatology the Second Hospital of Dalian Medical UniversityDalianLiaoning Province116021China Department of Cell Biology Dalian Medical UniversityDalianLiaoning Province116044China

Objective:To investigate the effect and possible mechanism of hydroxysafflor yellow A(HSYA) on human immortalized keratinocyte cell proliferation and migration.Methods:HaCaT cells were treated with HSYA.Cell proliferation was detected by the cell counting kit-8 assay,and cell migration was measured using wound healing assay and Transwell migration assay.The mRNA and protein expression levels of heparin-binding epidermal growth factor(EGF)-like growth factor(HBEGF),EGF receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),and hypoxia-inducible factor-1α(HIF-1α) were detected by quantitative real-time polymerase chain reaction(qRT-PCR) and Western blot,respectively.Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA.The expression of circ_0084443 was detected by qRT-PCR.Results:HSYA(800 μmol/L) significantly promoted HaCaT cell proliferation and migration(P0.05).Conclusion:HSYA played an accelerative role in HaCaT cell proliferation and migration,which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways,and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.

关键词： hydroxysafflor yellow A circ_0084443 heparin-binding epidermal growth factor-like growth factor/epidermal growth factor receptor phosphatidylinositol 3-kinase/protein kinase B

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