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Extensive carbon cycle between peatland and vegetation: Insights from high net primary productivity of the Middle Jurassic in northwestern China

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Journal of Palaeogeography 2024年第4期13卷 1016-1028页

作者： Yang-Yang Huang Hao Liang long-Yi shao Bin Yang Baruch Spiro Jia-Min Zhou Jing Lu Tan-Guang Fan State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources College of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) Research Institute of Exploration & Development PetroChina Tuha Oilfield Company Exploration Company PetroChina Tuha Oilfield Company Department of Earth Sciences Natural History Museum School of Marine Sciences University of Haifa

Peatlands have obvious carbon storage capacity and are crucial in mitigating global climate *** the end-product of peatlands,coals have preserved a large amount of palaeoenvironmental *** carbon accumulation rate and the net primary productivity （NPP） of coal-forming peatlands can be used as proxies for recovering palaeoenvironments.A super-thick coal seam （42°3.'N,91°25'E） was developed in the Middle Jurassic Xishanyao Formation in the Shaerhu coalfield in the southern margin of the Tuha （Turpan-Hami） Basin,northwestern *** this study,we use the time series analysis to identify the periods of Milankovitch orbital cycles in the Gamma-ray curve of this super-thick （124.85 m） coal and then use the obtained cycle periods of 405 ka,173.ka,44 ka,3..6 ka,22.5 ka to calculate the timeframe of the coalforming peatlands which ranges from 2703.44 to 2975.11 *** that the carbon content of the coal seam is 78.3.%and the carbon loss during the coalification is about 25.80%,the carbon accumulation rate of the targeted coal seam is estimated to be 58.47-64.3. g C/m2·a,and the NPP is estimated to be252.28-277.63.g C/m2·*** main palaeoenvironmental factors controlling the NPP of peatlands are CO2content,palaeolatitude and *** reduced NPP values of the palaeo-peatlands in the Shaerhu coalfield can be attributed to the mid-palaeolatitude and/or too low atmospheric *** a certain extent,the NPP of palaeo-peatlands reflects the changes in atmospheric CO2,which can further reveal the dynamic response of the global carbon cycle to climate ***,predicting the level of NPP in the Middle Jurassic and studying the final destination of carbon in the ecosystem are beneficial to understanding the coal-forming process and palaeoenvironment.

关键词： Xishanyao Formation Super-thick coal Milankovitch cycle Carbon accumulation rate Carbon cycle

CRD-CGAN:category-consistent and relativistic constraints for diverse text-to-image generation

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Frontiers of Computer Science 2024年第1期18卷 61-75页

作者： Tao HU Chengjiang long Chunxia XIAO College of Intelligent Systems Science and Engineering Hubei Minzu UniversityEnshi 445000China School of Computer Science Wuhan UniversityWuhan 430072China Key Laboratory of Performing Art Equipment&System Technology Ministry of Culture and TourismBeijing 100007China Meta Reality Labs BurlingameCA94010USA

Generating photo-realistic images from a text description is a challenging problem in computer *** works have shown promising performance to generate synthetic images conditional on text by Generative Adversarial Networks(GANs).In this paper,we focus on the category-consistent and relativistic diverse constraints to optimize the diversity of synthetic *** on those constraints,a category-consistent and relativistic diverse conditional GAN(CRD-CGAN)is proposed to synthesize K photo-realistic images *** use the attention loss and diversity loss to improve the sensitivity of the GAN to word attention and ***,we employ the relativistic conditional loss to estimate the probability of relatively real or fake for synthetic images,which can improve the performance of basic conditional ***,we introduce a category-consistent loss to alleviate the over-category issues between K synthetic *** evaluate our approach using the Caltech-UCSD Birds-200-2011,Oxford 102 flower and MS COCO 2014 datasets,and the extensive experiments demonstrate superiority of the proposed method in comparison with state-of-the-art methods in terms of photorealistic and diversity of the generated synthetic images.

关键词： text-to-image diverse conditional GAN relativi-stic category-consistent

A new twist to the interplay between superconductivity and Kondo correlation

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 1-2页

作者： Gui-Lu long Department of Physics Tsinghua UniversityBeijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Recently,Deng et al.[1] found a new twist to the intriguing physics resulting from the interplay between Kondo correlation and *** correlation [2,3. and superconductivity [4,5] are two fundamental phenomena in condens... 详细信息

关键词： Kondo twist

Multicolored Bipartite Ramsey Numbers of Large Cycles

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 347-357页

作者： shao-qiang LIU Yue-jian PENG College of Mathematics and Statistics Hanshan Normal UniversityChaozhou 521041China School of Mathematics Hunan UniversityChangsha 410082China

For an integer r≥2 and bipartite graphs Hi,where 1≤i≤r,the bipartite Ramsey number br(H1,H2,…,Hr)is the minimum integer N such that any r-edge coloring of the complete bipartite graph KN;N contains a monochromatic subgraph isomorphic to Hi in color i for some 1≤i≤*** show that if r≥3.α1,α2>0,αj+2≥[(j+2)!-1]Σi=1^(j+1)α1 for j=1,2…r-2,then br(C2[α1n],C2[α2n],…,C2[αrn]=(Σ=j=1^(r)a j+o(1))n.

关键词： ramsey number bipartite ramsey number regularity lemma

Experimental Study on Wire Melting Control Ability of Twin-Body Plasma Arc

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 184-194页

作者： Ruiying Zhang Fan Jiang long Xue School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Beijing Academy of Safety Engineering and Technology Beijing 102617China College of Mechanical and Energy Engineering Beijing University of TechnologyBeijing 100124China

The twin-body plasma arc has the decoupling control ability of heat transfer and mass transfer,which is beneficial to shape and property control in wire arc additive *** this paper,with the wire feeding speed as a characteristic quantity,the wire melting control ability of twin-body plasma arc was studied by adjusting the current separation ratio(under the condition of a constant total current),the wire current/main current and the position of the wire in the arc axial *** results showed that under the premise that the total current remains unchanged(100 A),as the current separation ratio increased,the middle and minimum melting amounts increased approximately synchronously under the effect of anode effect power,the first melting mass range remained constant;the maximum melting amount increased twice as fast as the middle melting amount under the effect of the wire feeding speed,and the second melting mass range was *** the wire current increased,the anode effect power and the plasma arc power were both factors causing the increase in the wire melting amount;however,when the main current increased,the plasma arc power was the only factor causing the increase in the wire melting *** average wire melting increment caused by the anode effect power was approximately 2.7 times that caused by the plasma arc *** minimum melting amount was not affected by the wire-torch distance under any current separation ratio *** the current separation ratio increased and reached a threshold,the middle melting amount remained constant with increasing wire-torch *** the current separation ratio continued to increase and reached the next threshold,the maximum melting amount remained constant with the increasing wire-torch *** effect of the wire-torch distance on the wire melting amount reduced with the increase in the current separation *** this study,the decoupling mechanism and ability of this innovative

关键词： Twin-body plasma arc Melting control ability Melting amount Current separation ratio

Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake

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Avian Research 2024年第2期15卷 187-195页

作者： Fucheng Yang Mingqin shao Jianying Wang College of Life Science Jiangxi Normal UniversityNanchang330022China

Extreme droughts are increasing in frequency and severity globally as a result of climate *** understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased *** numerous studies have investigated birds’responses to drought,the emphasis has primarily been on *** can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains *** this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in *** indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the ***-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental *** time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller ***,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the *** the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging *** accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging *** a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental ***-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the pisc

关键词： Climate change Extreme drought Foraging behavior Oriental stork Poyang lake

Anti-inflammatory and DNA Repair Effects of Astragaloside IV on PC12 Cells Damaged by Lipopolysaccharide

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Current Medical Science 2024年第4期44卷 854-863页

作者： Hai-long LI Li-hua shao Xi CHEN Meng WANG Qi-jie QIN Ya-li YANG Guang-run ZHANG Yang HAI Yi-hong TIAN Department of Geriatrics The Affiliated Hospital of Gansu University of Chinese MedicineLanzhou730000China Key Laboratory for Mining Innovation and Transformation of Traditional Chinese Medicine in Gansu Province and the New Product Creation Engineering Laboratory of Traditional Chinese Medicine in Gansu ProvinceLanzhou730000China Department of Neurology the First People’s Hospital of LanzhouLanzhouGansu730000China School of Public Health Gansu University of Chinese MedicineLanzhou730000China People’s Hospital of Gansu Province Lanzhou730000China Scientific Research and Experimental Center Gansu University of Chinese MedicineLanzhou730000China

Objective This study aimed to establish a neural cell injury model in vitro by stimulating PC12 cells with lipopolysaccharide(LPS)and to examine the effects of astragaloside IV on key targets using high-throughput sequence technology and bioinformatics *** PC12 cells in the logarithmic growth phase were treated with LPS at final concentrations of 0.25,0.5,0.75,1,and 1.25 mg/mL for 24 *** morphology was evaluated,and cell survival rates were calculated.A neurocyte inflammatory model was established with LPS treatment,which reached a 50%cell survival ***12 cells were treated with 0.01,0.1,1,10,or 100µmol/L astragaloside IV for 24 *** concentration of astragaloside IV that did not affect the cell survival rate was selected as the treatment group for subsequent *** activity was detected by colorimetry;the expression levels of ERCC2,XRCC4,XRCC2,TNF-α,IL-1β,TLR4,NOS and COX-2 mRNA and protein were detected by RT-qPCR and Western *** differentially expressed genes(DEGs)between the groups were screened using a second-generation sequence(fold change>2,P0.05).However,after treatment with 0.5,0.75,1,or 1.25 mg/mL LPS for 24 h,the viability steadily decreased(P<0.01).The mRNA and protein expression levels of ERCC2,XRCC4,XRCC2,TNF-α,IL-1β,TLR4,NOS,and COX-2 were significantly increased after PC12 cells were treated with 1 mg/mL LPS for 24 h(P<0.01);however,these changes were reversed when PC12 cells were pretreated with 0.01,0.1,or 1µmol/L astragaloside IV in PC12 cells and then treated with 1 mg/mL LPS for 24 h(P<0.05).Second-generation sequencing revealed that 1026 genes were upregulated,while 1287 genes were downregulat

关键词： PC12 cells astragaloside IV inflammation DNA damage

Chien-physics-informed neural networks for solving singularly perturbed boundary-layer problems

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1467-1480页

作者： long WANG Lei ZHANG Guowei HE The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

A physics-informed neural network(PINN)is a powerful tool for solving differential equations in solid and fluid ***,it suffers from singularly perturbed boundary-layer problems in which there exist sharp changes caused by a small perturbation parameter multiplying the highest-order *** this paper,we introduce Chien's composite expansion method into PINNs,and propose a novel architecture for the PINNs,namely,the Chien-PINN(C-PINN)*** novel PINN method is validated by singularly perturbed differential equations,and successfully solves the wellknown thin plate bending *** particular,no cumbersome matching conditions are needed for the C-PINN method,compared with the previous studies based on matched asymptotic expansions.

关键词： physics-informed neural network(PINN) singular perturbation boundarylayer problem composite asymptotic expansion

Effect of the interval between two shocks on ejecta formation from the grooved aluminum surface

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Defence Technology（防务技术） 2024年第3期33卷 147-159页

作者： Mingyang Xu Jianli shao Weidong Song Enling Tang School of Equipment Engineering Shenyang Ligong UniversityShenyang 110159China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical *** unsupported shocks are obtained by the plate-impact between sample and two flyers at interval,with a peak pressure of approximately 3. GPa for each *** the shock interval varies from 2.11 to 7.67 times the groove depth,the bubble velocity reduces to a constant,and the micro jetting factor R_(J) from spike to bubble exhibits a non-monotonic change that decreases initially and then *** a shock interval of 3.6 times the groove depth,micro jetting factor R_(J) from spike to bubble reaches its minimum value of approximately ***,the micro jetting factor R_(F) from spike to free surface decreases linearly at first,and stabilizes around 0.25 once the shock interval surpasses 4.18 times the groove *** the shock interval is less than 4.18 times the groove depth,the unloading wave generated by the breakout of the first shock wave is superimpose with the unloading part of the second shock wave to form a large tensile area.

关键词： Ejecta Microjet Two shocks Interval Smoothed particle hydrodynamics