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Discrepant responses of soil organic carbon dynamics to nitrogen addition in different layers: a case study in an agroecosystem

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 314-325页

作者： Hualing HU Liang ZHAO Wenbing TAN Guoan WANG Beidou XI technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China state Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

Empirical research indicates that heightened soil nitrogen availability can potentially diminish microbial decomposition of soil organic carbon(SOC).Nevertheless, the relationship between SOC turnover response to N addition and soil depth remains unclear. In this study, soils under varying N fertilizer application rates were sampled up to 100 cm deep to examine the contribution of both new and old carbon to SOC across different soil depths,using a coupled carbon and nitrogen isotopic approach. The SOC turnover time for the plot receiving low N addition(250 kg·ha^(-1)·yr^(-1) N) was about 20-40 years. Conversely, the plot receiving high N(450 kg·ha^(-1)·yr^(-1) N) had a longer SOC turnover time than the low N plot, reaching about 100 years in the upper 10-20 cm layer. The rise in SOC over the entire profile with low N addition primarily resulted from an increase in the upper soil(0-40 cm)whereas with high N addition, the increase was mainly from greater SOC in the deeper soil(40-100 cm). Throughout the entire soil layer, the proportion of new organic carbon derived from maize C_4 plant sources was higher in plots treated with a low N rate than those treated with a high N rate. This implies that, in contrast to low N addition agricultural practices, high N addition predominantly enhances the soil potential for fixing SOC by transporting organic matter from surface soils to deeper layers characterized by more stable properties. This research offers a unique insight into the dynamics of deep carbon under increased N deposition, thereby aiding in the formulation of policies for soil carbon management.

关键词： ^(13)C natural abundance nitrogen addition soil depth organic carbon turnover

Neutrino oscillations in the Non-Kerr black hole with quantum phenomenon

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Chinese Physics C 2024年第7期48卷 55-66页

作者： Husan Alibekov Farruh Atamurotov Ahmadjon Abdujabbarov Vokhid Khamidov Ulugh Beg Astronomical Institute Astronomy St.33Tashkent 100052Uzbekistan university of Tashkent for Applied Sciences Str.Gavhar 1Tashkent 100149Uzbekistan New Uzbekistan university Movarounnahr street 1Tashkent 100000Uzbekistan Tashkent state technical university Tashkent 100095Uzbekistan Institute of Theoretical Physics National University of UzbekistanTashkent 100174Uzbekistan Institute of Fundamental and Applied Research National Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan Tashkent university of Information Technologies named after Muhammad al Khwarizmi Amir Temur 108Tashkent 100014Uzbekistan

In this study,we have investigated the mathematical components of the Dirac equation in curved spacetime and how they can be applied to the analysis of neutrino *** specifically,we have developed a method for calculating the phase shift in flavor neutrino oscillations by utilizing a Taylor series expansion of the action that takes into account△m^(4) *** addition,we have used this method to assess how the phase difference in neutrino mass eigenstates changes according to the gravitational field described by the Johannsen spacetime.

关键词： Dirac equation neutrino flavour oscillation curved spacetime D0I:10.1088/1674-1137/ad3c2c

A Railway Fastener Inspection Method Based on Abnormal Sample Generation

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 565-592页

作者： Shubin Zheng Yue Wang Liming Li Xieqi Chen Lele Peng Zhanhao Shang Higher Vocational and technical College Shanghai University of Engineering ScienceShanghai200437China School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China Shanghai Engineering Research Centre of Vibration and Noise Control Technologies for Rail Transit Shanghai University of Engineering ScienceShanghai201620China

Regular fastener detection is necessary to ensure the safety of ***,the number of abnormal fasteners is significantly lower than the number of normal fasteners in real *** supervised inspectionmethods have insufficient detection ability in cases of imbalanced *** solve this problem,we propose an approach based on deep convolutional neural networks(DCNNs),which consists of three stages:fastener localization,abnormal fastener sample generation based on saliency detection,and fastener state ***,a lightweight YOLOv5s is designed to achieve fast and precise localization of fastener ***,the foreground clip region of a fastener image is extracted by the designed fastener saliency detection network(F-SDNet),combined with data augmentation to generate a large number of abnormal fastener samples and balance the number of abnormal and normal ***,a fastener inspection model called Fastener ResNet-8 is constructed by being trained with the augmented fastener *** show the effectiveness of our proposed method in solving the problem of sample imbalance in fastener *** and quantitative comparisons show that the proposed F-SDNet outperforms other state-of-the-art methods in clip region extraction,reaching MAE and max F-measure of 0.0215 and 0.9635,*** addition,the FPS of the fastener state inspection model reached 86.2,and the average accuracy reached 98.7%on 614 augmented fastener test sets and 99.9%on 7505 real fastener datasets.

关键词： Railway fastener sample generation inspection model deep learning

A Disturbance Localization Method for Power System Based on Group Sparse Representation and Entropy Weight Method

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Energy Engineering 2024年第8期121卷 2275-2291页

作者： Zeyi Wang Mingxi Jiao Daliang Wang Minxu Liu Minglei Jiang He Wang Shiqiang Li Changchun Power Supply Company State Grid Jilin Electric Power Co.Ltd.Changchun130021China Economic and technical Research Institute State Grid Jilin Electric Power Co.Ltd.Changchun130022China Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Northeast Electric Power UniversityJilin132012China

This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sparse representation and entropy weight *** different electrical quantities are selected as observations in the compressed sensing *** entropy weighting method is employed to calculate the weights of different observations based on their relative disturbance ***,by leveraging the topological information of the power system and pre-designing an overcomplete dictionary of disturbances based on the corresponding system parameter variations caused by disturbances,an improved Joint Generalized Orthogonal Matching Pursuit(J-GOMP)algorithm is utilized for *** reconstructed sparse vectors are divided into three *** at least two parts have consistent node identifiers,the node is identified as the disturbance *** the node identifiers in all three parts are inconsistent,further analysis is conducted considering the weights to determine the disturbance *** results based on the IEEE 39-bus system model demonstrate that the proposed method,utilizing electrical quantity information from only 8 measurement points,effectively locates disturbance positions and is applicable to various disturbance types with strong noise resistance.

关键词： Disturbance location compressed sensing group sparse representation entropy power method GOMP algorithm

Finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.Y.Eayal AWWAD Khosro FALLAHNEZHAD B.F.YOUSIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

A novel TNKS/USP25 inhibitor blocks the Wnt pathway to overcome multi-drug resistance in TNKS-overexpressing colorectal cancer

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Acta Pharmaceutica Sinica B 2024年第1期14卷 207-222页

作者： Hongrui Zhu Yamin Gao Liyun Liu Mengyu Tao Xiao Lin Yijia Cheng Yaoyao Shen Haitao Xue Li Guan Huimin Zhao Li Liu Shuping Wang Fan Yang Yongjun Zhou Hongze Liao Fan Sun Houwen Lin Research Center for Marine Drugs Department of PharmacyRen Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Oncology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Institute of Marine Drugs Guangxi University of Chinese MedicineNanning 530200China state Key Laboratory of New Drug and Pharmaceutical Process Shanghai Professional and Technical Ser-vice Center for Biological Material Drug-ability EvaluationShanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 200437China Institute of Marine Biomedicine Shenzhen PolytechnicShenzhen 518055China

Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin ***,we identified UAT-B,a novel neoantimycin analog isolated from Streptomyces conglobatus,as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction(PPI)to overcome multi-drug resistance in colorectal cancer(CRC).The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels,triggering cell apoptosis through modulation of the Wnt/β-catenin ***,UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels,as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts,as well as APC^(min/+)spontaneous CRC ***,these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment,and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.

关键词： Colorectal cancer TNKSeUSP25 interaction Multi-drug resistance TNKS overexpression Wnt pathway Apoptosis Neoantimycin analog

Ternary layered boride MoAlB:A novel thermo-regulation microwave absorbing ceramic material

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Journal of Advanced Ceramics 2024年第5期13卷 699-710页

作者： Zhangjue Wang Fan Zhang Nannan Wang Wei Li Yongqiang Chen Hailong Wang Rui Zhang Yanqiu Zhu Bingbing Fan School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Academy of Sciences Zhengzhou 450046China state Key Laboratory of Featured Metal Materials and Life Cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China Department of Engineering Faculty of EnvironmentScience and EconomyUniversity of ExeterExeter EX44QFUK

In the context of the fifth-generation(5G)smart era,the demand for electromagnetic wave(EMW)-absorbing materials has become increasingly prominent,so it is necessary to explore promising candidate *** work focuses on the exploration of the material absorbing properties of a MoAlB MAB(MAB represents a promising group of alternatives,where M stands for a transition metal,A typically denotes Al,and B is boron)phase ***,the first-principles calculations were performed to reveal the unique crystal and layered structure of the MoAlB ceramics and to predict their potential for use as an EMW absorption ***,a series of MoAlB ceramics were synthesized at temperatures ranging from 800 to 1300℃,and the influence of temperature on the phase compositions and microstructures of the obtained MoAlB ceramics was characterized and ***,the practical EMW absorption performance of the prepared MoAlB ceramics was evaluated via a combination of experiments and radar cross-sectional *** MoAlB sample synthesized at 900℃ exhibits superior EMW absorption performance,achieving an impressive minimum reflection loss(RL)of−50.33 *** unique layered structure and good electrical conductivity of the MoAlB samples are the main reasons for their enhanced wave absorption performance,which provides interfacial polarization and multiple dielectric loss ***,this study not only contributes to the understanding of the preparation of MoAlB materials but also provides potential guidance for their utilization in the realm of electromagnetic wave absorption.

关键词： MoAlB electronic band structure electromagnetic wave(EMW)absorption layered ternary boride density of states

Development of a novel signal restoration algorithm to eliminate the distorted components in space charge measurement excited by femtosecond laser irradiation

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High Voltage 2024年第3期9卷 659-673页

作者： Tianrun Qi Hanwen Ren Haoyu Gao Qingmin Li Yidan Ma Yiqun Ma Tao Xiao state Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

For the space charge measurement method with optical excitation for electrical insulation,the distortion of the excitation laser on the measurement signal and the accumulation of space charge have not been discussed *** experiment and simulation results show that three types of distorted components introduced by optical excitation can lead to distortion of the upper interface ***,the factors causing distortion of the measured signal and the formation mechanism are analysed.A virtual electrode potential compensation method and a distorted component extraction method are ***,an attenuation restoration and charge conversion correction factor is intro-duced,leading to a novel signal processing algorithm adapted to space charge optical measurement *** with the traditional algorithm,the novel algorithm has an error of less than 1%in the calculation of charge and electric field strength,with an increase in accuracy of 47.7%and 9.81%,*** applying the novel restoration algorithm,the comparison shows that the space charge accumulation does not change significantly under laser irradiation,verifying the reliability of the optical *** given algorithm can provide a theoretical and technical foundation for the realisation of the optical measurement method for space charge.

关键词： charge algorithm excitation

Correlation of Microbiological Stability with Redox Processes in White Wines

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Food and Nutrition Sciences 2024年第3期15卷 211-223页

作者： Gheorghe Duca Rodica Sturza Natalia Vladei Ecaterina Covaci Research Centre of Physical and Inorganic Chemistry State University of Moldova Chisinau Republic of Moldova Department of Oenology and Chemistry Faculty of Food Technology Technical University of Moldova Chisinau Republic of Moldova

In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines.

关键词： White Wines Acetobacter Sulfur Dioxide Redox Processes Oxygen