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Multistate transition and coupled solid-liquid modeling of motion process of long-runout landslide

Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2694-2714页

作者： yang Gao Yueping Yin Bin Li Han Zhang Weile Wu Haoyuan Gao Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing100081China China Institute of Geological Environment Monitoring China Geological SurveyBeijing100081China School of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

The recognition,repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological *** this study,a new numerical method involving LPF3D based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and *** following results were obtained:(a)The motion process of landslides showed a steric effect with mobility,including gradual disintegration and *** sliding mass can be divided into three states(dense,dilute and ultradilute)in the motion process,which can be solved by three dynamic regimes(friction,collision,and inertial);(b)Coupling simulation between the solid grain and liquid phases was achieved,focusing on drag force influences;(c)Different algorithms and constitutive models were employed in phase-state *** volume fraction is an important indicator to distinguish different state types and solid‒liquid *** flume experimental results were favorably validated against long-runout landslide case data;and(d)In this method,matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides,and the advantages of continuum media and discrete media were combined to improve the computational accuracy and *** new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

关键词： Long-runout landslide Multistate transition Mixed solid‒liquid flow Post-failure process Numerical simulation

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Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy

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Journal of Traditional Chinese Medicine 2024年第2期44卷 345-352页

作者： ZHANG Xinchang HUANG Zheng HUANG Peiyan yang Mengning ZHANG Zhihui NI Guangxia College of Acupuncture-Moxibustion and Tuina Nanjing University of Chinese MedicineNanjing 210023China Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023China

OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ***:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture *** 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce *** rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)*** neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after *** chloride staining was applied to assess the cerebral infarct volume at 24 h after *** malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay *** blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTH1)at 24 h after ***,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence ***:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture *** CIRI,the expression of NCOA4,LC3 and FTH1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic ***,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTH1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

关键词： acupuncture ferritinophagy ferroptosis ferritin nuclear receptor coactivator 4 cerebral ischaemia-reperfusion injury

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Seasonal Variation of Hearing Sensitivity in the Red-eared Slider(Trachemys scripta elegans)

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Asian Herpetological Research 2024年第2期15卷 82-89页

作者： Tongliang WANG Jinxia yang Handong LI Jinhong LEI Haitao SHI Jichao WANG Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158HainanChina

Seasonal variation of hearing sensitivity has been observed in many vertebrate groups with obvious vocal *** hormones,conspecific calling signals,and temperature are potential factors that drive these plasticity *** have a hearing range that appears to be limited to under 1.5 kHz and are often thought to be non-vocal;thus,they are commonly neglected in vocal communication *** this study,we aimed to determine whether the auditory phenotype exhibits seasonal variation in sensitivity and to analyze the potential factors driving such variation patterns in *** measured hearing sensitivity and sex hormone levels in female(estradiol)and male(testosterone and dihydrotestosterone)Red-eared sliders(Trachemys scripta elegans)during spring and *** results showed that auditory brainstem response(ABR)thresholds were significantly lower in spring than in winter at a frequency range of 0.5-0.9 *** hearing-sensitivity bandwidth was wider,and the ABR latency was significantly shorter in spring than in *** significant differences were found in estradiol,testosterone,and dihydrotestosterone levels in *** elegans between spring and *** study is the first to reveal the seasonal variation of peripheral hearing sensitivity in turtles,a special animal group with limited hearing range and less *** variations may be used to explain these seasonal effects,but further research is required to confirm our findings.

关键词： auditory plasticity seasonal variation temperature turtles

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A Deep Learning Approach for Forecasting Thunderstorm Gusts in the Beijing–Tianjin–Hebei Region

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Advances in Atmospheric Sciences 2024年第7期41卷 1342-1363页

作者： Yunqing LIU Lu yang Mingxuan CHEN Linye SONG Lei HAN Jingfeng XU Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China

Thunderstorm gusts are a common form of severe convective weather in the warm season in North China,and it is of great importance to correctly forecast *** present,the forecasting of thunderstorm gusts is mainly based on traditional subjective methods,which fails to achieve high-resolution and high-frequency gridded forecasts based on multiple observation *** this paper,we propose a deep learning method called Thunderstorm Gusts TransU-net(TGTransUnet)to forecast thunderstorm gusts in North China based on multi-source gridded product data from the Institute of Urban Meteorology(IUM)with a lead time of 1 to 6 *** determine the specific range of thunderstorm gusts,we combine three meteorological variables:radar reflectivity factor,lightning location,and 1-h maximum instantaneous wind speed from automatic weather stations(AWSs),and obtain a reasonable ground truth of thunderstorm ***,we transform the forecasting problem into an image-to-image problem in deep learning under the TG-TransUnet architecture,which is based on convolutional neural networks and a *** analysis and forecast data of the enriched multi-source gridded comprehensive forecasting system for the period 2021–23 are then used as training,validation,and testing ***,the performance of TG-TransUnet is compared with other *** results show that TG-TransUnet has the best prediction results at 1–6 *** IUM is currently using this model to support the forecasting of thunderstorm gusts in North China.

关键词： thunderstorm gusts deep learning weather forecasting convolutional neural network transformer

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Twisted Integration of Complex Oxide Magnetoelectric Heterostructures via Water‑Etching and Transfer Process

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Nano-Micro Letters 2024年第1期16卷 360-369页

作者： Guannan yang Guohua Dong Butong Zhang Xu Xu yanan Zhao Zhongqiang Hu Ming Liu State Key Laboratory for Manufacturing Systems Engineering Electronic Materials Research LaboratoryKey Laboratory of the Ministry of EducationEngineering Research Center of Spin Quantum Sensor ChipsUniversities of Shaanxi ProvinceSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049People’s Republic of China

Manipulating strain mode and degree that can be applied to epitaxial complex oxide thin films have been a cornerstone of strain *** recent years,lift-off and transfer technology of the epitaxial oxide thin films have been developed that enabled the integration of heterostructures without the limitation of material types and crystal ***,twisted integration would provide a more interesting strategy in artificial magnetoelectric heterostructures.A specific twist angle between the ferroelectric and ferromagnetic oxide layers corresponds to the distinct strain regulation modes in the magnetoelectric coupling process,which could provide some insight in to the physical *** this work,the La_(0.67)Sr_(0.33)MnO_(3)(001)/0.7Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)(011)(LSMO/PMN-PT)heterostructures with *** *** angles were assembled via water-etching and transfer *** transferred LSMO films exhibit a fourfold magnetic anisotropy with easy axis along LSMO.A coexistence of uniaxial and fourfold magnetic anisotropy with LSMO[110]easy axis is observed for the 45°Sample by applying a 7.2 kV cm^(−1)electrical field,significantly different from a uniaxial anisotropy with LSMO[100]easy axis for the 0°*** fitting of the ferromagnetic resonance field reveals that the strain coupling generated by the 45°twist angle causes different lattice distortion of LSMO,thereby enhancing both the fourfold and uniaxial *** work confirms the twisting degrees of freedom for magnetoelectric coupling and opens opportunities for fabricating artificial magnetoelectric heterostructures.

关键词： Magnetoelectric heterostructures Twist angle Epitaxial lift-off Magnetic anisotropy Ferromagnetic resonance

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Identification of transient receptor potential channel genes and functional characterization of TRPA1 in Spodoptera frugiperda

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Journal of Integrative Agriculture 2024年第6期23卷 1994-2005页

作者： Yutong Zhang Hangwei Liu Song Cao Bin Li yang Liu Guirong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory *** receptor potential(TRP)channels,which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in *** channels have been widely investigated for their critical roles in regulating various insect behaviors in recent *** this study,we identified 15 TRP gene loci encoding 26 transcripts in the genome of *** and analyzed their expression profiles at different developmental *** results revealed that *** possesses four TRPC genes,six TRPA genes,one TRPM gene,two TRPV genes,one TRPN gene,and one TRPML gene,while a canonical TRPP is ***,the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression *** results showed that SfruTRPA1 is activated by temperature increases from 20 to 45℃,and there is no significant desensitization after repeated stimuli within the same temperature ***,SfruTRPA1 is activated by certain natural chemicals,including allyl isothiocyanate(AITC)and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in ***.

关键词： Spodoptera frugiperda transient receptor potential channel expression profile TRPA1 Xenopus oocyte

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基于近红外光谱技术的气体浓度检测研究

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激光杂志 2024年第3期45卷 253-257页

作者：梁良杜雨馨杨子建徐州工程学院机电工程学院江苏徐州221018

气体浓度在各领域分析中具有重要意义,由于在气体浓度检测过程中,受光谱维度的影响导致检测结果出现较大的误差,为了降低在测量过程中产生的不利影响,提出基于近红外光谱技术的气体浓度检测研究。通过去势-标准正态变换,校正近红外光谱... 详细信息

气体浓度在各领域分析中具有重要意义,由于在气体浓度检测过程中,受光谱维度的影响导致检测结果出现较大的误差,为了降低在测量过程中产生的不利影响,提出基于近红外光谱技术的气体浓度检测研究。通过去势-标准正态变换,校正近红外光谱基线。联合广义S变换和奇异值分解共同去噪近红外光谱,提升光谱质量。基于主成分分析提出偏最小二乘降维法用于降维近红外光谱。以朗伯比尔定律为基础,引入Lorenz线性拟合近红外光谱吸收谱线,采用梯度下降法直接拟合预处理近红外光谱吸收信号,计算得到最终气体浓度检测结果。实验结果表明,所提方法在检测甲苯、丙烷和丙烯气体浓度时,检测结果与实际气体浓度基本一致,有效降低了残差平方和与均方根误差,且检测时间低于2.3 s。

关键词：近红外光谱技术气体浓度检测奇异值分解偏最小二乘降维梯度下降法

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The behaviors of gas-liquid two-phase flow under gas kick during horizontal drilling with oil-based muds

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Petroleum 2024年第1期10卷 49-67页

作者： Yu Su Huiyun Ma Jianhua Guo Xinyu Shen Zhaoliang yang Jie Wu Engineering Technology Research Institute PetroChina Southwest Oil & Gas Field Company

Natural gas is easily soluble in oil-based muds(OBM), leading to complex flow behavior in wellbores,especially in horizontal wells. In this study, a new transient flow model considering wellbore-formation coupling and gas solubility on flow behavior is developed to simulate gas kicks during horizontal drilling with OBM. Furthermore, the effect of gas solubility on parameters such as bottom-hole pressure(BHP),gas void fraction and mixture velocity in the flow behavior is analyzed. Finally, several critical factors affecting flow behavior are investigated and compared to gas kicks in water-based muds(WBM) where the effect of solubility is neglected. The results show that the invading gas exists as dissolved gas in the OBM and as free gas in the WBM. Before the gas escapes from the OBM, the pit gain is zero and there is barely any change in the BHP, annulus return flow rate and mixture velocity, which means that detecting gas kicks through these warning signs can be challenging until they get very close to the surface and develop rapidly. However, in WBM drilling, these parameters change quickly with the increasing gas kick time. Additionally, for both cases, the longer the horizontal length and the greater reservoir permeability,the greater the decrease in BHP, and the shorter the time for gas to migrate from the bottom-hole to the wellhead. A larger flow rate contributes to a greater initial BHP and a lesser BHP reduction. This research is of value in characterizing gas kick behavior and identifying novel ways for early gas kick detection during horizontal drilling with OBM.

关键词： Flow behavior Gas solubility Gas kick Horizontal drilling Oil-based muds Water-based muds

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Towards accurate mapping of loess waterworn gully by integrating google earth imagery and DEM using deep learning

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International Soil and Water Conservation Research 2024年第1期12卷 13-28页

作者： Rong Chen Yi Zhou Zetao Wang Ying Li Fan Li Feng yang School of Geography and Tourism Shaanxi Normal UniversityXi'an710119China National Experiment and Teaching Demonstration Center for Geography Xi'an710119China SuperMap Software Co. Ltd.Beijing100015China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Accurate mapping of loess waterworn gully(LWG)is essential to further study gully erosion and geomorphological evolution for the Chinese Loess Plateau(CLP).Due to the vertical joint and collapsibility of loess,LWGs have the characteristics of zigzag and unique slope abruptness under synthetic action of hydraulic force and *** forces existing LWG mapping methods to either focus on the improvement of mapping accuracy or center on the increase of mapping ***,simultaneously achieving accurate and efficient mapping of LWG is still in its infancy under complex topographic ***,we proposed a method that innovatively integrates the loess slope abruptness feature into an improved deep learning semantic segmentation framework for LWG mapping using 0.6 m Google imagery and 5 m DEM *** selected four study areas representing typical loess landforms to test the performance of our *** proposed method can achieve satisfactory mapping results,with the F1 score,mean Intersection-over-Union(mIoU),and overall accuracy of 90.5%,85.3%,and 92.3%,*** addition,the proposed model also showed significant accuracy improvement by inputting additional topographic information(especially the slope of slope).Compared with existing algorithms(Random forests,original DeepLabV3+,and Unet),the proposed approach in this study achieved a better accuracy-efficiency ***,the method can ensure high accuracy and efficiency of the LWG mapping for different loess landform types and can be extended to study various loess gully mapping and water and soil conservation.

关键词： Loess waterworn gully Topographic information Mapping Deep learning Soil erosion Loess plateau

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Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research International 2024年第1期31卷 143-156页

作者： An-gang Ning yang Liu Rui Gao Stephen Yue Ming-bo Wang Han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

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