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From the dust:extracellular vesicles as regulators of development and neuroregeneration

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Neural Regeneration Research 2024年第5期19卷 933-934页

作者： Leon G.Coleman jr The University of North Carolina at Chapel Hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

First impressions can have a lasting *** science,this can be especially problematic,because our lack of understanding often causes us to mislabel and thus ignore important biological *** this vein,extracellular vesicles(EVs)were once considered to be“cellular dust”.Similar to the previous concept of“junk DNA”to describe protein non-coding regions,EVs are far more than just cellular *** fact,EVs are emerging as key mediators of intracellular communication across nearly all biological *** includes peripheral immune responses(e.g.,arthropathies and sepsis),intra-organ communication(Seim et al.,2023),and a host of other physiological and pathological states(Figure 1A and B).

关键词： Figure extracellular

Lift-Off Effect of Koch and Circular Differential Pickup Eddy Current Probes

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 283-293页

作者： Guolong Chen Zheng cao Shuaishuai Zhang Ji Wei Wei Gao Wuyin Jin School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

A flexible or planar eddy current probe with a differential structure can suppress the lift-off noise during the inspection of ***,the extent of the lift-off effect on differential probes,including different coil structures,*** this study,two planar eddy current probes with differential pickup structures and the same size,Koch and circular probes,were used to compare lift-off *** eddy current distributions of the probes perturbed by 0°and 90°cracks were obtained by finite element *** analysis results show that the 90°crack can impede the eddy current induced by the Koch probe even further at relatively low lift-off *** peak-to-peak values of the signal output from the two probes were compared at different lift-off distances using finite element analysis and experimental *** addition,the effects of different frequencies on the lift-off were studied *** results show that the signal peak-to-peak value of the Koch probe for the inspection of cracks in 90°orientation is larger than that of the circular probe when the lift-off distance is smaller than 1.2 *** addition,the influence of the lift-off distance on the peak-to-peak signal value of the two probes was studied via *** indicates that the influence becomes more evident with an increase in excitation *** research discloses the lift-off effect of differential planar eddy current probes with different coil shapes and proves the detection merit of the Koch probe for 90°cracks at low lift-off distances.

关键词： Eddy current testing Differential pickup probe Fractal Koch curve Flexible eddy current probe

Land use and cover change and influencing factor analysis in the Shiyang River Basin,China

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Journal of Arid Land 2024年第2期16卷 246-265页

作者： ZHAO Yaxuan cao Bo SHA Linwei CHENG Jinquan ZHAO Xuanru GUAN Weijin PAN Baotian Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030China Shiyang River Basin Scientific Observing Station Lanzhou UniversityLanzhou 730030China

Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and social *** economic development and climate change have resulted in significant changes in land use and *** Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant climate change and LUCC over the past few *** this study,we used the random forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat *** validated the land use and cover data in 2015 from the random forest classification results(this study),the high-resolution dataset of annual global land cover from 2000 to 2015(AGLC-2000-2015),the global 30 m land cover classification with a fine classification system(GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this ***,we explored and compared the spatiotemporal patterns of LUCC in the upper,middle,and lower reaches of the Shiyang River Basin over the past 30 years,and employed the random forest importance ranking method to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,temperature,and surface soil moisture)and anthropogenic(nighttime light,gross domestic product(GDP),and population)*** results indicated that the random forest classification results for land use and cover in the Shiyang River Basin in 2015 outperformed the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial ***,the classification results in this study exhibited a high level of agreement with the ground truth *** 1991 to 2020,the area of bare land exhibited a decreasing trend,with chan

关键词： land use and cover classification land use and cover change(LUCC) climate change random forest accuracy assessment three-dimensional sampling method Shiyang River Basin

Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek jr. Yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Enhancement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Science & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou Qichi Le Ye Shi Qiyu Liao Tong Wang Qi Zou Clodualdo Aranas jr Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried *** is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix under suitable heat treatment *** remainder is diffusely distributed as rods or granules at the grain *** excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the *** substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for ***,the dissolution of the MgZnCu phase weakens the hindering effect of the second phase on grain boundary migration,setting the stage for *** addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its *** ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the welded joints are 255 MPa,119 MPa and 27.0%,respectively,under the post-weld heat treatment process of 440℃×12 *** welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

SnRK1a1, a new player in the sucrose-Opaque2 network during endosperm filling

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Molecular Plant 2024年第8期17卷 1172-1174页

作者： Kelly Mayrink Balmant Marcio F.R.Resende jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(Oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(Flint-Garcia et al.,2009).

关键词： endosperm reservoir Flint

Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1322-1332页

作者： Qinghe Cui Xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik jr. Dzmitry Bahrets Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the *** technology has a very broad application prospect in industrial *** have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this *** this review,metals were classified according to their crystal *** effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were *** main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism

Fish culture in biofloc technology(BFT):Insights on stocking density carbon sources,C/N ratio,fish nutrition and health

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Aquaculture and Fisheries 2024年第4期9卷 522-533页

作者： Luciana Kelly Oliveira Wilson Wasielesky jr Marcelo Borges Tesser Laboratorio de Nutriçao de Organismos Aqu´aticos Instituto de OceanografiaUniversidade Federal do Rio Grande-FURG-Rua do Hotel02-CassinoRio Grande96201-900Brazil Laborat´orio de Carcinocultura Instituto de OceanografiaUniversidade Federal do Rio Grande-FURG-Rua do Hotel02-CassinoRio Grande96201-900Brazil

The growth of aquaculture demands intense consumption of formulated foods,scarce natural resources such as water and *** increase in aquaculture production needs to be sustainable in several aspects of the activity,including the use of more sustainable farming systems that provide reduced water demand,less space dependence for increased production,and availability of complementary natural *** this perspective,the biofloc system(BFT),presents itself as a more friendly cultivation technology as a way to mitigate some impacts of aquaculture *** research has been carried out,addressing different aspects important to the production of fish in *** this review,we address how stocking density,carbon sources and carbon nitrogen ration(C/N)affect animal performance and the nutritional value of bioflocs;the use of microbial aggregates as“in situ”and“ex situ”food and the benefits in feed conversion,and their influence on the immune system and disease resistance.

关键词： Biofloc technology Aquaculture system Natural food Nutritional value Fish health

Climate bonds toward achieving net zero emissions and carbon neutrality:Evidence from machine learning technique

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Journal of Management Science and Engineering 2024年第1期9卷 1-15页

作者： Hermas Abudu Presley K.Wesseh jr. Boqiang Lin College of Overseas Education Chengdu UniversityChengdu610106SichuanChina School of Management China Institute for Studies in Energy PolicyCollaborative Innovation Center for Energy Economics and Energy PolicyXiamen UniversityFujian361005China Center for African Development Strategy(CFADS) MonroviaLiberia

The Conference of the Parties(COP26 and 27)placed significant emphasis on climate financing policies with the objective of achieving net zero emissions and carbon ***,studies on the implementation of this policy proposition are *** address this gap in the literature,this study employs machine learning techniques,specifically natural language processing(NLP),to examine 77 climate bond(CB)policies from 32 countries within the context of climate *** findings indicate that“sustainability”and“carbon emissions control”are the most outlined policy objectives in these CB ***,the study highlights that most CB funds are invested toward energy projects(i.e.,renewable,clean,and efficient initiatives).However,there has been a notable shift in the allocation of CB funds from climate-friendly energy projects to the construction sector between 2015 and *** shift raises concerns about the potential redirection of funds from climate-focused investments to the real estate industry,potentially leading to the greenwashing of climate ***,policy sentiment analysis revealed that a minority of policies hold skeptical views on climate change,which may negatively influence climate ***,the findings highlight that the effective implementation of CB policies depends on policy goals,objectives,and ***,this study contributes to the literature by employing NLP techniques to understand policy sentiments in climate financing.

关键词： Climate bonds funds utilization Climate bonds policy text mining Machine learning technique Net zero emissions Policy sentiment analysis