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Infiltration,runoff,and slope stability behaviors of infinite slope with macropores based on an improved Green–Ampt model

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Journal of Mountain Science 2024年第7期21卷 2220-2235页

作者： LI Shanghui WU Guoxiong QUE Yun JIANG Zhenliang CHENG Gaoyun college of Intelligent Construction Fuzhou University of International Studies and TradeFuzhou 350202China college of Civil Engineering Chongqing Jiao Tong UniversityChongqing 400074China Chongqing Vocational college of Architectural Engineering Chongqing 400072China college of Civil Engineering Fuzhou UniversityFuzhou 350000China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong Kong 999077China T.Y.Lin International Engineering Consulting(China)Co.Ltd Chongqing 401120China

Infiltration–runoff–slope instability mechanism of macropore slope under heavy rainfall is *** paper studied its instability mechanism with an improved Green–Ampt(GA)model considering the dual-porosity(i.e.,matrix and macropore)and ponding condition,and proposed the infiltration equations,infiltration–runoff coupled model,and safety factor calculation *** show that the infiltration processes of macropore slope can be divided into three stages,and the proposed model is rational by a comparative *** wetting front depth of the traditional unsaturated slope is 17.2%larger than that of the macropore slope in the early rainfall stage and 27%smaller than that of the macropore slope in the late rainfall ***,macropores benefit the slope stability in the early rainfall but not in the *** flow does not occur initially but becomes pronounced with increasing rainfall *** equal depth of the wetting front in the two domains is regarded as the onset criteria of macropore *** analysis shows that macropore flow is delayed by increasing proportion of macropore domain(ω_(f)),whereas promoted by increasing ratio of saturated permeability coefficients between the two domains(μ).The increasing trend of ponding depth is sharp at first and then grows ***,when rainfall duration is less than 3 h,ωf andμhave no significant effect on the safety factor,whereas it decreases with increasingωf and increases with increasingμunder longer duration(≥3 h).With the increase ofω_(f),the slope maximum instability time advances by 10.5 h,and with the increase ofμ,the slope maximum instability time delays by 3.1 h.

关键词： Macropore slope Green–Ampt infiltration model Equivalent wetting front Ponding response time Slope stability

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Global existence and large-time behavior for primitive equations with the free boundary

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Science China Mathematics 2024年

作者： Hailiang Li Chuangchuang Liang School of Mathematical Sciences Capital Normal University Academy for Multidisciplinary studies Capital Normal University college of Mathematics and Statistics Chongqing University

In the present paper, the primitive equations, which can be used to simulate the large-scale motion of the ocean and atmosphere, are considered in the three-dimensional domain bounded below by a fixed solid boundary and above by a free-moving boundary. The global existence and uniqueness of strong solutions are established, and the long-time convergence to the equilibrium state is shown to be either at an exponential rate for the horizontal periodic domain or at an algebraic rate for the horizontal whole space.

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Westward Migration of Tropical Cyclone Activity in the Western North Pacific during 1982–2020:Features and Possible Causes

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Journal of Meteorological Research 2024年第1期38卷 1-9页

作者： Jian ZHONG Huadong DU Yuqin WU Yuehua PENG China Satellite Maritime Tracking and Control Department Jiangyin 2144312 college of Advanced Interdisciplinary studies National University of Defense TechnologyChangsha 4100733 Dalian Naval Academy Dalian 1160184 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

The westward migration of tropical cyclone(TC)activity has been identified in the western North Pacific(WNP),but the related features and causes remain ***,based on the best track data from China,Japan,and the US,and the NCEP–NCAR reanalysis data in 1982–2020,we investigate characteristics of the westward migration of the WNP TC activity with various metrics,and reveal possible causes for the migration of TC tracks through analyzing its seasonality and dependence on environmental *** results show that the WNP TCs show significant westward migrations in a number of metrics,including location of tracks,genesis,the first track point at which TC reaches its lifetime-maximum intensity,and the last track point in the TC *** is found that TC tracks exhibit more significant westward migrations in the easterly steering flow than in the westerly steering ***,the TC longitude shift shows notable seasonal variations,for which the TCs in the easterlies move further west than those in the westerlies during July–September,vice versa during October–*** dependence of the westward migration of TC tracks on background steering flow is associated with the different environmental *** westward shift in the westerly steering is mainly due to the reduced vertical wind shear(VWS),while the weakened zonal easterly steering and reduced VWS are both closely related to the westward migration in the easterly *** results have important implications for understanding current and future variations in TC longitude shift.

关键词： tropical cyclone westward migration steering flow vertical wind shear

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Exploring Sequential Feature Selection in Deep Bi-LSTM Models for Speech Emotion Recognition

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Computers, Materials & Continua 2024年第2期78卷 2689-2719页

作者： Fatma Harby Mansor Alohali Adel Thaljaoui Amira Samy Talaat Computer Science Department Future Academy-Higher Future Institute for Specialized Technological StudiesCairo12622Egypt Department of Computer Science and Information college of Science at Zulfi Majmaah UniversityP.O.Box 66Al-Majmaah11952Saudi Arabia Preparatory Institute for Engineering studies of Gafsa ZarrougGafsa2112Tunisia Computers and Systems Department Electronics Research InstituteCairo12622Egypt

Machine Learning(ML)algorithms play a pivotal role in Speech Emotion Recognition(SER),although they encounter a formidable obstacle in accurately discerning a speaker’s emotional *** examination of the emotional states of speakers holds significant importance in a range of real-time applications,including but not limited to virtual reality,human-robot interaction,emergency centers,and human behavior *** identifying emotions in the SER process relies on extracting relevant information from audio *** studies on SER have predominantly utilized short-time characteristics such as Mel Frequency Cepstral Coefficients(MFCCs)due to their ability to capture the periodic nature of audio signals *** these traits may improve their ability to perceive and interpret emotional depictions appropriately,MFCCS has some *** this study aims to tackle the aforementioned issue by systematically picking multiple audio cues,enhancing the classifier model’s efficacy in accurately discerning human *** utilized dataset is taken from the EMO-DB database,preprocessing input speech is done using a 2D Convolution Neural Network(CNN)involves applying convolutional operations to spectrograms as they afford a visual representation of the way the audio signal frequency content changes over *** next step is the spectrogram data normalization which is crucial for Neural Network(NN)training as it aids in faster *** the five auditory features MFCCs,Chroma,Mel-Spectrogram,Contrast,and Tonnetz are extracted from the spectrogram *** attitude of feature selection is to retain only dominant features by excluding the irrelevant *** this paper,the Sequential Forward Selection(SFS)and Sequential Backward Selection(SBS)techniques were employed for multiple audio cues features ***,the feature sets composed from the hybrid feature extraction methods are fed into the deep Bidirectional Long Short

关键词： Artificial intelligence application multi features sequential selection speech emotion recognition deep Bi-LSTM

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Intrinsic polarization conversion and avoided-mode crossing in X-cut lithium niobate microrings

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Chinese Physics B 2024年第6期33卷 398-403页

作者：谭泽林张检发朱志宏陈伟邵铮铮刘肯秦石乔 college of Advanced Interdisciplinary studies&Hunan Provincial Key Laboratory of Novel Nano Optoelectronic Information Materials and Devices National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China college of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China School of Physics Central South UniversityChangsha 410083China

Compared with well-developed free space polarization converters, polarization conversion between TE and TM modes in the waveguide is generally considered to be caused by shape birefringence, like curvature, morphology of waveguide cross section and scattering. Here, we study the polarization conversion mechanism in 1-THz-FSR X-cut lithium niobate microrings with multiple-resonance condition, that is the conversion can be implemented by birefringence of waveguides,which will also introduce an avoided-mode crossing. In the experiment, we find that this mode crossing results in severe suppression of one sideband in local nondegenerate four-wave mixing and disrupts the cascaded four-wave mixing on this side. Simultaneously, we propose one two-dimensional method to simulate the eigenmodes(TE and TM) in X-cut microrings, and the mode crossing point. This work will provide one approach to the design of polarization converters and simulation for monolithic photonics integrated circuits, and may be helpful to the studies of missed temporal dissipative soliton formation in X-cut lithium niobate rings.

关键词： polarization conversion birefringence nondegenerate four-wave mixing

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A Graded Speed Control Method for Cyborg Rats Based on Electrical Stimulation of the Cuneiform Nucleus

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Journal of Bionic Engineering 2024年第3期21卷 1334-1346页

作者： Hanyi Ling Le Han Nenggan Zheng Qiushi Academy for Advanced studies(QAAS) Zhejiang UniversityHangzhou310007China The State Key Lab of Brain-Machine Intelligence Zhejiang UniversityHangzhou310007China college of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310007China college of Computer Science and Technology Zhejiang UniversityHangzhou310007China CCAI by MOE and Zhejiang Provincial Government(ZJU) Hangzhou310007China

The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg ***,the current stimulation techniques cannot realize the graded control of the *** this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration *** concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg *** the amplitude of stimulation was found to affect the response time exhibited by the cyborg *** study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.

关键词： Cyborg rats Cuneiform nucleus Graded control Speed regulation

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Regulation of AMPK activation by extracellular matrix stiffness in pancreatic cancer

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Genes & Diseases 2024年第3期11卷 338-350页

作者： Xin Xu Yuan Fang Somaira Nowsheen Ye-Xiong Li Zhenkun Lou Min Deng State Key Laboratory of Molecular Oncology and Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of general Surgery Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China Department of general Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Department of Dermatology University of California San DiegoSan DiegoCA 92093USA Department of Oncology Mayo ClinicRochesterMN 55905USA

The adenosine monophosphate(AMP)-activated protein kinase(AMPK)sits at a cen-tral node in the regulation of energy metabolism and tumor *** is best known to sense high cellular ADP or AMP levels,which indicate the depletion of energy *** studies have shown that the low expression of phosphorylated AMPK is associated with a poor prognosis of pancreatic *** this study,we report that AMPK is also highly sensitive to extracellular matrix(ECM)*** found that AMPK is activated in cells when cultured under low ECM stiffness conditions and is functionally required for the metabolic switch induced by ECM *** regulation of AMPK requires the Hippo kinases but not LKB1/*** kinases directly phosphorylate AMPKa at Thr172 to activate AMPK at low ECM ***,we found AMPK activity is inhibited in patients with pancreatic ductal adenocarcinoma(PDAC)with high ECM stiffness and is associated with a poor survival *** activation of Hippo kinases by ROCK inhibitor Y-27632 in combination with the mitochondrial inhibitor metformin synergistically activates AMPK and dramatically inhibits PDAC ***,these findings establish a novel model for AMPK regulation by the mechanical properties of ECMs and provide a rationale for simultaneously targeting the ECM stiffness-Hippo kinases-AMPK signaling and low glucose-LKB1-AMPK signaling pathways as an effective therapeutic strategy against PDAC.

关键词： AMPKactivity Cellularmetabolic switch ECM stiffness Hippokinase signaling Pancreaticductal adenocarcinoma

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NbN quantum dots anchored hollow carbon nanorods as efficient polysulfide immobilizer and lithium stabilizer for Li-S full batteries

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Journal of Energy Chemistry 2024年第1期88卷 260-271,I0007页

作者： Fei Ma Zhuo Chen Katam Srinivas Ziheng Zhang Yu Wu Dawei Liu Hesheng Yu Yue Wang Xinsheng Li Ming-qiang Zhu Qi Wu Yuanfu Chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and TechnologyChengdu 610054SichuanChina college of Science and Institute of Oxygen Supply Center of Tibetan Studies(Everest Research Institute)Tibet UniversityLhasa 850000TibetChina college of Mechanical and Electronic Engineering Northwest A&F UniversityXianyang 712100ShaanxiChina

The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)*** simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full *** functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite *** a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 *** at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 *** study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode.

关键词： Dual-functional host NbN quantum dots Shuttle effect Dendrite-free Li anode Li-S full batteries

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Bismuth clusters pinned on TiO_(2) porous nanowires boosting charge transfer for CO_(2) photoreduction to CH_(4)

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Nano Research 2024年第3期17卷 1190-1198页

作者： Jiazhi Meng Kaiwen Wang Yang Wang Jiangping Ma Chaogang Ban Yajie Feng Bin Zhang Kai Zhou Liyong Gan Guang Han Danmei Yu Xiaoyuan Zhou college of Physics and Institute of Advanced Interdisciplinary studies Chongqing UniversityChongqing 401331China School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China college of Materials Science and Engineering Chongqing UniversityChongqing 400044China Beijing Key Lab of Microstructure and Properties of Advanced Materials Beijing University of TechnologyBeijing 100124China Analytical and Testing Center Chongqing UniversityChongqing 401331China

Artificial photosynthesis in carbon dioxide(CO_(2))conversion into value-added chemicals attracts considerable attention but suffers from the low activity induced by sluggish separation of photogenerated carriers and the kinetic bottleneck-induced unsatisfied ***,we prepare a new-style Bi/TiO_(2) catalyst formed by pinning bismuth clusters on TiO_(2) nanowires through being confined by pores,which exhibits high activity and selectivity towards photocatalytic production of CH_(4) from CO_(2).Boosted charge transfer from TiO_(2) through Bi to the reactants is revealed via in situ X-ray photon spectroscopy and time-resolved photoluminescence(PL).Further,in situ Fourier transform infrared results confirm that Bi/TiO_(2) not only overcomes the multi-electron kinetics challenge of CO_(2) to CH_(4) via boosting charge transfer,but also facilitates proton production and transfer as well as the intermediates*CHO and*CH_(3)O generation,ultimately achieving the tandem catalysis towards *** calculation also underlies that the more favorable reaction step from*CO to*CHO on Bi/TiO_(2) results in CH_(4) production with higher *** work brings new insights into rational design of photocatalysts with high performance and the formation mechanism of CO_(2) to CH_(4) for solar energy storage in future.

关键词： carbon dioxide(CO_(2))photoreduction charge transfer tandem catalysis methanation

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Resection of polyps involving the appendiceal orifice by combined endo-laparoscopic surgery: Two case reports

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1948-1952页

作者： Yue-Yi Zhang Jun-Yang Lu Qiang Wang Ai-Ming Yang Department of Gastroenterology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of general Surgery State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

BACKGROUND The management of polyps involving the appendiceal orifice(AO)presents notable *** resection is frequently hindered by operational complexities,a heightened risk of incomplete removal,and an elevated risk of procedural complications,including ***,surgical resection may entail unnecessary excision of intestinal segments,leading to potential *** SUMMARY Here,we reported two patients who presented with polyps deeply situated within the AO,with indistinct boundaries making it challenging to ensure completeness using traditional endoscopic *** overcome these challenges,we em-ployed combined endo-laparoscopic surgery(CELS),achieving curative resection without postoperative *** The application of CELS in managing polyps involving the AO is emerging as a safe and effective treatment modality.

关键词： Polyps Laterally spreading tumor Appendiceal orifice Endoscopic resection Combined endo-laparoscopic surgery Case report

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