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Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： xu Liu xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among Masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

Face Anti-Spoofing with Unknown Attacks:A Comprehensive Feature Extraction and Representation Perspective

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Journal of Computer Science & Technology 2024年第4期39卷 827-840页

作者： Li-Min Li Bin-Wu wang xu wang Peng-Kun wang yu-Dong Zhang Yang wang School of Software Engineering University of Science and Technology of ChinaHefei 230000China School of Data Science University of Science and Technology of ChinaHefei 23000China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215000China

Face anti-spoofing aims at detecting whether the input is a real photo of a user(living)or a fake(spoofing)*** new types of attacks keep emerging,the detection of unknown attacks,known as Zero-Shot Face Anti-Spoofing(ZSFA),has become increasingly important in both academia and *** ZSFA methods mainly focus on extracting discriminative features between spoofing and living ***,the nature of the spoofing faces is to trick anti-spoofing systems by mimicking the livings,therefore the deceptive features between the known attacks and the livings,which have been ignored by existing ZSFA methods,are essential to comprehensively represent the ***,existing ZSFA models are incapable of learning the complete representations of living faces and thus fall short of effectively detecting newly emerged *** tackle this problem,we propose an innovative method that effectively captures both the deceptive and discriminative features distinguishing between genuine and spoofing *** method consists of two main components:a two-against-all training strategy and a semantic *** two-against-all training strategy is employed to separate deceptive and discriminative *** address the subsequent invalidation issue of categorical functions and the dominance disequilibrium issue among different dimensions of features after importing deceptive features,we introduce a modified semantic *** autoencoder is designed to map all extracted features to a semantic space,thereby achieving a balance in the dominance of each feature *** combine our method with the feature extraction model ResNet50,and experimental results show that the trained ResNet50 model simultaneously achieves a feasible detection of unknown attacks and comparably accurate detection of known *** results confirm the superiority and effectiveness of our proposed method in identifying the living with the interference of both known

关键词： face anti-spoofing spoof detection zero-shot learning convolutional neural network deep learning

Toward tunable shape memory effect of NiTi alloy by grain size engineering:A phase field study

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Journal of Materials Science & Technology 2024年第1期168卷 276-289页

作者： Bo xu Chong wang Qingyuan wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering (Sichuan University)Ministry of EducationChengdu 610065China

The inelastic deformations of shape memory alloys(SMAs)always show poor controllability due to the avalanche-like martensite transformation,and the effective control for the deformation of precision de-vices has been not yet *** this work,the phase field method was used to investigate the shape memory effects(SMEs)of NiTi SMAs undergoing grain size(GS)engineering,to obtain tunable one-way and stress-assisted two-way SMEs(OWSME and SATWSME).The OWSME and SATWSME of the systems with various gradient-nanograin structures and bimodal grain structure,as well as that with geometric gradients were *** simulated results indicate that due to the GS dependences of martensite transformation and reorientation,the occurrence and expansion of martensite reorientation,martensite transformation and its reverse can be efficaciously controlled via the GS *** combining the GS engineering and geometric gradient design,since the effects of GS and stress gradient can be su-perimposed or competing,and the responses of martensite reorientation,martensite transformation and its reverse to this are different,the OWSME and SATWSME of the geometrically graded systems with various nanograin structures can exhibit different improvements in *** short,the reorienta-tion hardening modulus during OWSME is increased and the transformation temperature window during SATWSME is widened by GS engineering,indicating the improved controllability of *** optimal GS engineering schemes revealed in this work provide the basic reference and guidance for designing tun-able SMEs and producing NiTi-based driving devices catering to desired functional performance in various engineering fields.

关键词： Phase field NiTi Shape memory effect Grain size engineering Geometric gradient

A nitroreductase-responsive nanoprobe with homogeneous composition and high loading for preoperative non-invasive tumor imaging and intraoperative guidance

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Chinese Chemical Letters 2024年第7期35卷 313-318页

作者： Jingqi Xin Shupeng Han Meichen Zheng Chenfeng xu Zhongxi Huang Bin wang Changmin yu Feifei An yu Ren Institute of Medical Engineering Department of BiophysicsSchool of Basic Medical ScienceHealth Science CenterXi'an Jiaotong UniversityXi'an 710061China School of Public Health Health Science CenterXi'an Jiaotong UniversityXi'an 710061China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing 211816China Department of Breast Surgery the First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061China

Tumor microenvironment(TME)-activatable probes have been proven to effectively increase signal-tobackground ratios(SBRs)and improve the success rate of complete tumor ***,many fluorescence probes have to be loaded into a nanocarrier for tumor targeted delivery,which consequently encounters poor drug loading,heterogeneous composition and non-encapsulated drug aggregates occurred during nanoformulation ***,a nitroreductase(NTR)-activated“OFF-ON”near-infrared fluorescence nanoprobe,named Nano Bodipy,was synthesized by the spontaneous self-assembling of NTRresponsive dye-polyethylene glycol(PEG)amphiphilic polymer in *** NTR-responsive dye acted as the hydrophobic segment in the amphiphilic polymer,yielding a homogeneous composition and a high loading of 12.2 wt%(according to calculation)in the synthesized Nano *** synthesized Nano Bodipy can efficiently accumulate in tumors via the enhanced permeability and retention(EPR)effect,enabling non-invasive tumor-targeted fluorescence imaging and guiding complete tumor *** the synthesized Nano Bodipy entered the tumor cells,they dissociated and were activated by overexpressed *** the real-time fluorescence guide of Nano Bodipy,complete tumor resection surgery was performed successfully.

关键词： Nitroreductase Tumor diagnosis Intraoperative guidance Self-assembly Nanoprobe

Quantifying trapping stability of optical tweezers with an external flow

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Photonics Research 2024年第8期12卷 1741-1749页

作者： FENG xu YARONG yu YANG LIU YAO CHANG WENXIANG JIAO LIN wang HOPUI HO BEI WU FEI xu YANQING LU yuANJIE PANG GUANGHUI wang College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China Key Laboratory of Intelligent Optical Sensing and Integration of the Ministry of Education Nanjing UniversityNanjing 210093China School of Optical and Electronic Information Wuhan National Laboratory of OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China Department of Biomedical Engineering The Chinese University of Hong KongHong Kong 999077China

Optical tweezers(OTs)can immobilize and manipulate objects with sizes that span between nano-and micrometer *** manipulating ability of OTs is traditionally characterized by stability factor(S),which can only indicate an empirical“hit-or-miss”***,the current quantitative models for trapping stability rarely consider the influence of external *** this paper,a comprehensive analysis to quantify the optical trapping stability in a perturbed asymmetric potential well is presented from the perspective of statistics,especially for weak trapping *** analytical formulation takes experimentally measurable parameters including particle size,optical power,and spot width as inputs and precisely outputs a statistically relevant mean trapping ***,this formulation takes into account general and realistic cases including fluidic flow velocity and other *** verify the model,a back-focal-plane-interferometer-monitored trapping experiment in a flow is set up and the statistical characteristics of trapping time demonstrate good agreement with theoretical *** total,the model quantitatively reveals the effects of external disturbance on trapping time,which will find applications where optical trapping stability is challenged by external perturbations in weak trapping conditions.

关键词： process flow trapping

Role of texture before rolling: a research based on texture and magnetic properties of 4.5 wt.% Si non-oriented electrical steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1973-1986页

作者： yu-fan wang Guo-qing Zu Shi-cheng Sun Ying Han Wei-wei Zhu Hui Wu yu Zhao xu Ran Key Laboratory of Advanced Structural Materials of Ministry of Education Changchun University of TechnologyChangchun 130012JilinChina CRRC Changchun Railway Vehicles Co. Ltd.Changchun 130000JilinChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia

The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(/ND(normal direction))before rolling of non-oriented electrical steel was *** recrystallized hot bands with different textures but similar grain sizes were prepared by pre-annealing at low-temperature and high-temperature normalization *** was observed that the final annealed products exhibited similar recrystallized *** contrast,the final annealed product with more 2 fiber before rolling exhibited a stronger cube *** the fiber before rolling becoming stronger,the proportion of(111)deformed matrices became larger,which could be observed in the early recrystallization *** overwhelmingly dominant 2 orientation nuclei are formed in the(111)deformed matrix and become the dominant ***,the best magnetic properties are obtained in the products with strong 2 fiber before rolling,corresponding to the strong cube texture and low anisotropyparameter.

关键词： Texture before rolling Non-oriented electrical steel-Nucleation Grain growth Magnetic property

Melatonin improves synapse development by PI3K/Akt signaling in a mouse model of autism spectrum disorder

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Neural Regeneration Research 2024年第7期19卷 1618-1624页

作者： Luyi wang Man xu Yan wang Feifei wang Jing Deng Xiaoya wang yu Zhao Ailing Liao Feng Yang Shali wang Yingbo Li Institute of Neuroscience Department of PhysiologySchool of Basic Medical ScienceChongqing Medical UniversityChongqingChina Department of Pediatric Chongqing University Fuling HospitalChongqingChina Department of Neurosurgery Xinqiao HospitalArmy Medical UniversityChongqingChina Department of Pathology Affiliated Hospital of North Sichuan Medical CollegeNanchongSichuan ProvinceChina NHC Key Laboratory of Birth Defects and Reproductive Health Chongqing Population and Family Planning Science and Technology Research InstituteChongqingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina

Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes,including Ctnnd2 as a candidate ***2knockout mice,serving as an animal model of autis m,have been demonstrated to exhibit decreased density of dendritic *** role of melatonin,as a neuro hormone capable of effectively alleviating social interaction deficits and regulating the development of dendritic spines,in Ctnnd2 deletion-induced nerve injury remains unclea *** the present study,we discove red that the deletion of exon 2 of the Ctnnd2 gene was linked to social interaction deficits,spine loss,impaired inhibitory neurons,and suppressed phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt) signal pathway in the prefrontal *** findings demonstrated that the long-term oral administration of melatonin for 28 days effectively alleviated the aforementioned abnormalities in Ctnnd2 gene-knockout ***,the administration of melatonin in the prefro ntal cortex was found to improve synaptic function and activate the PI3K/Akt signal pathway in this *** pharmacological blockade of the PI3K/Akt signal pathway with a PI3K/Akt inhibitor,wo rtmannin,and melatonin receptor antagonists,luzindole and 4-phenyl-2-propionamidotetralin,prevented the melatonin-induced enhancement of GABAergic synaptic *** findings suggest that melatonin treatment can ameliorate GABAe rgic synaptic function by activating the PI3K/Akt signal pathway,which may contribute to the improvement of dendritic spine abnormalities in autism spectrum disorders.

关键词： autism Ctnnd2 deletion GABAergic neurons melatonin PI3K/Akt signal pathway prefrontal cortex social behavior spine density synaptic-associated proteins

Influence of meteorological factors on open biomass burning at a background site in Northeast China

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Journal of Environmental Sciences 2024年第4期138卷 1-9页

作者： yulong wang Linlin Liang Wanyun xu Chang Liu Hongbing Cheng yusi Liu Gen Zhang Xiaobin xu Dajiang yu Peng wang Qingli Song Jiumeng Liu yuan Cheng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China Longfengshan Regional Background Station China Meteorological AdministrationHeilongjiang 150200China Heilongjiang Climate Center Heilongjiang 150030China

Biomass burning(BB)is a very important emission source that significantly adversely impacts regional air *** produces a large number of primary organic aerosol(POA)and black carbon(BC).Besides,BB also provides many precursors for secondary organic aerosol(SOA)*** this work,the ratio of levoglucosan(LG)to organic carbon(OC)and the fire hotspots map was used to identify the open biomass burning(OBB)events,which occurred in two representative episodes,October 13 to November 30,2020,and April1 to April 30,*** ratio of organic aerosol(OA)to reconstructed PM_(2.5)concentration(PM_(2.5)^(*))increased with the increase of LG/*** LG/OC ratio is higher than 0.03,the highest OA/PM_(2.5)^(*)ratio can reach 80%,which means the contribution of OBB to OA is *** to the ratio of LG to K^(+),LG to mannosan(MN)and the regional characteristics of Longfengshan,it can be determined that the crop residuals are the main *** occurrence of OBB coincides with farmers’preferred choices,i.e.,burning biomass in“bright weather”.The“bright weather”refers to the meteorological conditions with high temperature,low humidity,and without *** factors indirectly affect regional biomass combustion pollution by influencing farmers’active choices.

关键词： Air pollution Biomass burning Meteorological factors Organic trace Agricultural fires

Highly Strong,Tough,and Cryogenically Adaptive Hydrogel Ionic Conductors via Coordination Interactions

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Research 2024年第3期2024卷 703-713页

作者： Zhuomin wang Siheng wang Lei Zhang He Liu xu xu Institute of Chemical Industry of Forestry Products Key Laboratory of Biomass Energy and MaterialJiangsu ProvinceKey Laboratory of Chemical Engineering of Forest ProductsNational Forestry and Grassland AdministrationNational Engineering Research Center of Low-Carbon Processing and Utilization of Forest BiomassJiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesChinese Academy of ForestryNanjing 210042China College of Chemical Engineering Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China.

Despite the promise of high flexibility and conformability of hydrogel ionic conductors,existing polymeric conductive hydrogels have long suffered from compromises in mechanical,electrical,and cryoadaptive properties due to monotonous functional improvement strategies,leading to lingering ***,we propose an all-in-one strategy for the preparation of poly(acrylic acid)/cellulose(PAA/Cel)hydrogel ionic conductors in a facile yet effective manner combining acrylic acid and salt-dissolved cellulose,in which abundant zinc ions simultaneously form strong coordination interactions with the two polymers,while free solute salts contribute to ionic conductivity and bind water molecules to prevent ***,the developed PAA/Cel hydrogel simultaneously achieved excellent mechanical,conductive,and cryogenically adaptive properties,with performances of 42.5 MPa for compressive strength,1.6 MPa for tensile strength,896.9%for stretchability,9.2 MJ m^(−3)for toughness,59.5 kJ m^(−2)for fracture energy,and 13.9 and 6.2 mS cm^(−1)for ionic conductivity at 25 and−70°C,*** by these features,the resultant hydrogel ionic conductor is further demonstrated to be assembled as a self-powered electronic skin(e-skin)with high signal-to-noise ratio for use in monitoring movement and physiological signals regardless of cold temperatures,with hinting that could go beyond high-performance hydrogel ionic conductors.

关键词： Highly freezing salts