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Research on the mechanism of the two-dimensional ultrasonic surface burnishing process to enhance the wear resistance for aluminum alloy

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Friction 2024年第3期12卷 490-509页

作者： Zhen-Yu ZHOU Qiu-yang ZHENG Yu LI Cong DING Guang-jian PENG Zhong-Yu PIAO College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China

The gradient nanostructure is machined on the aluminum(Al)alloy by the two-dimensional ultrasonic surface burnishing process(2D-USBP).The mechanism of why the gradient nanostructure enhances wear resistance is *** mechanical properties and microstructure characterization for the gradient nanostructure are performed by operating a nanoindenter,transmission electron microscopy(TEM),and electron backscattered diffraction(EBSD).Dry wear tests are performed on the samples before and after machining to evaluate the wear resistance and *** effect of the gradient nanostructure on the wear resistance is explored by developing the crystal plasticity(CP)finite element and molecular dynamics(MD)*** characterization results show that the 2D-USBP sample prepared a gradient structure of~600μm thick on the aluminum surface,increasing the surface hardness from 1.13 to 1.71 GPa and reducing the elastic modulus from 78.84 to 70.14 *** optimization of the surface microstructure and the increase of the mechanical properties effectively enhance the wear resistance of the sample,with 41.20%,39.07%,and 54.58% of the wear scar areas for the 2D-USBP treated samples to the original samples under 5,10,and 15 N loads,*** gradient nanostructure hinders the slip of dislocations inside the sample during the wear process and reduces the size and scope of plastic deformation;meanwhile,the resistance to deformation,adhesion,and crack initiation and propagation of the sample surface is improved,resulting in enhanced wear resistance.

关键词： structural superlubricity lattice registry elastic deformation strained solitons crystal plasticity molecular dynamics simulations

Successful treatment of Purpureocillium lilacinum pulmonary infection with isavuconazole: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1772-1777页

作者： Xue-Lin yang Jun-Yu Zhang jian-Min Ren Department of Emergency Medicine Lishui Central HospitalLishui 323000Zhejiang ProvinceChina Department of Hematology Lishui Central HospitalLishui 323000Zhejiang ProvinceChina Department of Clinical Laboratory The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND Purpureocillium lilacinum(***)is a saprophytic fungus widespread in soil and *** a causative agent,it is very rarely detected in humans,most commonly in the *** SUMMARY In this article,we reported the case of a 72-year-old patient with chronic lymphocytic leukemia who was admitted with cough and *** tomography revealed an infection in the right lower *** lavage fluid culture and metagenomic next-generation sequencing were ultimately confirmed to have a pulmonary infection with *** was eventually discharged with good outcomes after treatment with *** Pulmonary infection with *** was exceedingly *** currently there are no definitive therapeutic agents,there are reports of high resistance to amphotericin B and fluconazole and good sensitivity to second-generation *** present report is the first known use of isavuconazole for pulmonary *** *** provides new evidence for the characterization and treatment of clinical *** lung infections.

关键词： Purpureocillium lilacinum Pulmonary infection Isavuconazole Case report

Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

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Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU jian LIU Shangbin HE Xiufeng yang Huashan DOU Honghai ZHANG School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

The Caching and Pricing Strategy for Information-Centric Networking with Advertisers’Participation

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China Communications 2024年第3期21卷 283-295页

作者： Zheng Quan Yan Wenliang Wu Rong Tan Xiaobin yang jian Yuan Liu Xu Zhenghuan Laboratory for Future Networks Department of AutomationUniversity of Science and Technology of ChinaHefei 230026China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China Suzhou Nuclear Power Research Institute Suzhou 215004China National Engineering Laboratory for Public Safety Risk Perception and Control by Big Data(NEL-PSRPC) China Academy of Electronics and Information Technology of CETCBeijing 100041China

As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’***,the Information-Centric Networking(ICN)came into *** a technical point of view,ICN is a promising future network *** and customizing a reasonable pricing mechanism plays a positive role in promoting the deployment of *** current research on ICN pricing mechanism is focused on paid ***,we study an ICN pricing model for free content,which uses game theory based on Nash equilibrium to *** this work,advertisers are considered,and an advertiser model is established to describe the economic interaction between advertisers and ICN *** solution can formulate the best pricing strategy for all ICN entities and maximize the benefits of each *** extensive analysis and numerical results show that the proposed pricing framework is significantly better than existing solutions when it comes to free content.

关键词： advertisers cache free content Information-Centric Networking pricing strategy

Metabolic and proteostatic differences in quiescent and active neural stem cells

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Neural Regeneration Research 2024年第1期19卷 43-48页

作者： Jiacheng Yu Gang Chen Hua Zhu Yi Zhong Zhenxing yang Zhihong jian Xiaoxing Xiong Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Adult neural stem cells are neurogenesis progenitor cells that play an important role in ***,neural regeneration may be a promising target for treatment of many neurological *** regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and *** adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell *** adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural *** review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein ***,we discuss the physiological significance and underlying advantages of these diffe *** to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.

关键词： adult neurogenesis cell metabolic pathway cellular proliferation neural stem cell niches neural stem cells neuronal differentiation nutrient sensing pathway proteostasis

Preliminary geological interpretation of long-wavelength magnetic anomalies over China and surrounding regions

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Earth and Planetary Physics 2024年第3期8卷 445-458页

作者： Jie Wang YanYan yang ZhiMa Zeren jian Wang Xin Wang YuXin Luo XuHui Shen National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing 100049China National Space Science Center Chinese Academy of SciencesBeijing 100190China

Long-wavelength(>500 km)magnetic anomalies originating in the lithosphere were first found in satellite magnetic *** to the striking magnetic anomalies around the world,the long-wavelength magnetic anomalies in China and surrounding regions are relatively *** research on each of these anomalies has been quite inadequate;their geological origins remain unclear,in particular their connection to tectonic activity in the Chinese and surrounding *** focus on six magnetic high anomalies over the(1)Tarim Basin,(2)Sichuan Basin(3)Great Xing’an Range,(4)Barmer Basin,(5)Central Myanmar Basin,and(6)Sunda and Banda Arcs,and a striking magnetic low anomaly along the southern part of the Himalayan-Tibetan *** have analyzed their geological origins by reviewing related research and by detailed comparison with geological *** tectonic backgrounds for these anomalies belong to two cases:either ancient basin basement,or subduction-collision ***,the geological origins of large-scale regional magnetic anomalies are always subject to dispute,mainly because of limited surface exposure of sources,later tectonic destruction,and superposition of multi-phase events.

关键词： long-wavelength magnetic anomaly lithospheric magnetic anomaly lithospheric magnetic field model satellite magnetic survey CSES

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： Yong yang Ren-Sheng CHEN Yong-jian DING Hong-Yuan LI Zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

Assessment of the three representative empirical models for zenith tropospheric delay(ZTD)using the CMONOC data

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Geodesy and Geodynamics 2024年第5期15卷 488-494页

作者： Debao Yuan jian Li Yifan Yao Fei yang Yingying Wang Ran Chen Tairan Xu College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing100083China Hubei Luojia Laboratory Wuhan430079China

The precise correction of atmospheric zenith tropospheric delay(ZTD)is significant for the Global Navigation Satellite System(GNSS)performance regarding positioning accuracy and convergence *** the past decades,many empirical ZTD models based on whether the gridded or scattered ZTD products have been proposed and widely used in the GNSS positioning *** there is no comprehensive evaluation of these models for the whole China region,which features complicated topography and *** this study,we completely assess the typical empirical models,the IGGtropSH model(gridded,non-meteorology),the SHAtropE model(scattered,non-meteorology),and the GPT3 model(gridded,meteorology)using the Crustal Movement Observation Network of China(CMONOC)*** general,the results show that the three models share consistent performance with RMSE/bias of 37.45/1.63,37.13/2.20,and 38.27/1.34 mm for the GPT3,SHAtropE and IGGtropSH model,***,the models had a distinct performance regarding geographical distribution,elevation,seasonal variations,and daily *** the southeastern region of China,RMSE values are around 50 mm,which are much higher than that in the western region,approximately 20 *** SHAtropE model exhibits better performance for areas with large variations in *** GPT3 model and the IGGtropSH model are more stable across different months,and the SHAtropE model based on the GNSS data exhibits superior performance across various UTC epochs.

关键词： GNSS Zenith tropospheric delay Empirical ZTD model CMONOC data

Drug-loading ZIF-8 for modification of microporous bone scaffold to promote vascularized bone regeneration

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Chinese Chemical Letters 2024年第6期35卷 358-364页

作者： Xin Zhang Junyu Chen Xiang Pei Linxin yang Liang Wang Luona Chen Guangmei yang Xibo Pei Qianbing Wan jian Wang State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesChengdu 610041China Department of Prosthodontics West China Hospital of StomatologySichuan UniversityChengdu 610041China

Surface modification of microporous bone scaffolds using nanoparticles has been broadly studied in bone tissue *** at improving vascularized bone regeneration(VBR),zeolitic imidazolate framework-8(ZIF-8)was encapsulated with dimethyloxallyl glycine(DMOG)and the drug-carrying nanoparticles(D@Z)could be uniformly coated onto the surface of the bone *** osteogenic and angiogenic actions of D@Z are closely correlated with the amount of slowly released DMOG,and in general,exhibited a favorable ***,the D7.5@Z group,which showed the greatest capacity to induce in vitro osteogenesis-angiogenesis coupling,was utilized for surface modification of the bone *** processes including phosphate-containing compound metabolic process,cell differentiation,cell proliferation and cell motility might contribute to enhanced ability to induce VBR by the coated scaffold and signaling pathways such as Rap1,Ras,phosphatidylinositol 3-kinase/protein kinase B(PI3K-AKT)and vascular endothelial growth factor(VEGF)signaling pathways participated in these ***,as depicted by in vitro real time-polymerase chain reaction(RT-PCR),Western blot(WB)and in vivo cranial bone defect model,the microporous scaffold coated with nano-D7.5@Z greatly promoted *** conclude,nano-D@Z has significant promise for practical application in modification of microporous bone scaffolds to enhance VBR,and DMOG loading quantity has a beneficial influence on D@Z to improve osteogenesis-angiogenesis coupling.

关键词： Drug-loading nanoparticles Surface coating Microporous bone scaffold Vascularization bone regeneration