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Dual-objective two-photon microscope for volumetric imaging of dense scattering biological samples by bidirectional excitation and collection

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Photonics Research 2024年第6期12卷 1351-1361页

作者： MUyuE zHAI JING yu YANHUI HU hang yu BEICHEN XIE YI yu DAWEI LI AIMIN WANG HEPING CHENG National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Research Unit of Mitochondria in Brain Diseases Chinese Academy of Medical SciencesPKU-Nanjing Institute of Translational MedicineNanjing 211500China Beijing Transcend Vivoscope Biotech Beijing 100085China College of Engineering Peking UniversityBeijing 100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China Center for Quantitative Biology Peking UniversityBeijing 100871China School of Electronics Peking UniversityBeijing 100871China State Key Laboratory of Advanced Optical Communication System and Networks Peking UniversityBeijing 100871China

Full view observation throughout entire specimens over a prolonged period is crucial when exploring the physiological functions and system-level ***-photon microscopy(MPM)has been widely employed for such purposes owing to its deep penetration ***,the current MPM struggles with balancing the imaging depth and quality while avoiding photodamage for the exponential increasement of excitation power with the imaging ***,we present a dual-objective two-photon microscope(Duo-2P),characterized by bidirectional two-photon excitation and fluorescence collection,for long-duration volumetric imaging of dense scattering ***-2P effectively doubles the imaging depth,reduces the total excitation energy by an order of magnitude for samples with a thickness five times the scattering length,and enhances the signal-to-noise ratio up to 1.4 *** these advantages,we acquired volumetric images of a 380-μm suprachiasmatic nucleus slice for continuous 4-h recording at a rate of 1.67 s/volume,visualized the calcium activities over 4000 neurons,and uncovered their state-switching *** conclude that Duo-2P provides an elegant and powerful means to overcome the fundamental depth limit while mitigating photodamages for deep tissue volumetric imaging.

关键词： excitation overcome exponential

Enhanced Ethylene Production from Electrocatalytic Acetylene Semi-hydrogenation Over Porous Carbon-Supported Cu Nanoparticles

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Transactions of Tianjin University 2024年第4期30卷 297-304页

作者： Li Li Fanpeng Chen Bo-hang zhao Yifu yu Institute of Molecular Plus Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Electrocatalytic semi-hydrogenation of acetylene(C_(2)H_(2))over copper nanoparticles(Cu NPs)offers a promising non-petroleum alternative for the green production of ethylene(C2H4).However,server hydrogen evolution reaction(HER)competition in this process prominently decreases C2H4 selectivity,thereby hindering its practical ***,a Cu-based composite catalyst,wherein porous carbon with nanoscale pores was used as a support,is constructed to gather the C_(2)H_(2) feedstocks for suppressing the undesirable *** a result,the as-prepared catalyst exhibited C_(2)H_(2) conversion of 27.1%and C_(2)H_(4) selectivity of 88.4%at a C2H4 partial current density of 0.25 A/cm^(2) under optimal−1.0 V versus reversible hydrogen electrode(RHE)under the simulated coal-derived C_(2)H_(2) atmosphere,significantly outperforming the single Cu NPs *** addition,a series of in situ and ex situ experimental results show that not only the porous nature of the carbon support but also the stabilized Cu^(0)–Cu^(+) dual active sites through the strong metal–support interactions enhance the adsorption capacity of C_(2)H_(2),leading to high C_(2)H_(2) partial pressure,restraining the HER and thus improving the C2H4 selectivity.

关键词： Electrocatalysis Cu-based catalyst Hydrogenation Ethylene Selectivity

Treadmill exercise improves hippocampal neural plasticity and relieves cognitive deficits in a mouse model of epilepsy

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Neural Regeneration Research 2024年第3期19卷 657-662页

作者： hang yu Mingting Shao Xi Luo Chaoqin Pang Kwok-Fai So Jiandong yu Li zhang Key Laboratory of CNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina State Key Laboratory of Brain and Cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina Department of Neurosurgery The First Affiliated Hospital of Bengbu Medical CollegeBengbuShandong ProvinceChina School of Psychology Shanghai University of SportShanghaiChina

Epilepsy frequently leads to cognitive dysfunction and approaches to treatment remain *** regular exercise effectively improves learning and memory functions across multiple neurological diseases,its application in patients with epilepsy remains ***,we adopted a 14-day treadmill-exercise paradigm in a pilocarpine injection-induced mouse model of *** assays confirmed the improvement of object and spatial memory after endurance training,and electrophysiological studies revealed the maintenance of hippocampal plasticity as a result of physical *** of the mechanisms underlying this effect revealed that exercise protected parvalbumin interneurons,probably via the suppression of neuroinflammation and improved integrity of blood-brain *** summary,this work identified a previously unknown mechanism through which exercise improves cognitive rehabilitation in epilepsy.

关键词： blood-brain barrier cognition hippocampus interneurons long-term potentiation microglial cell neuroinflammation spatial memory temporal epilepsy treadmill exercise

Development of a novel staging classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction after neoadjuvant chemotherapy

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2541-2554页

作者： Jian zhang Hao Liu hang yu Wei-Xiang Xu Department of Gastrointestinal Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Stage classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction(AEG)treated with neoadjuvant chemotherapy(NAC)has not been *** To investigate the optimal stage classification for Siewert Ⅱ AEG with *** A nomogram was established based on Cox regression model that analyzed variables associated with overall survival(OS)and disease-specific survival(DSS).The nomogram performance in terms of discrimination and calibration ability was evaluated using the likelihood-ratio test,Akaike information criterion,Harrell concordance index,time-receiver operating characteristic curve,and decision curve *** Data from 725 patients with Siewert type Ⅱ AEG who underwent neoadjuvant therapy and gastrectomy were obtained from the Surveillance,Epidemiology,and End Results *** and multivariate analyses revealed that sex,marital status,race,ypT stage,and ypN stage were independent prognostic factors of OS,whereas sex,race,ypT stage,and ypN stage were independent prognostic factors for *** factors were incorporated into the OS and DSS *** novel nomogram model performed better in terms of OS and DSS prediction compared to the 8th American Joint Committee of Cancer pathological staging system for esophageal and gastric ***,a user-friendly web application was developed for clinical *** The nomogram established specifically for patients with Siewert type Ⅱ AEG receiving NAC demonstrated good prognostic *** using external data is warranted before its widespread clinical application.

关键词： Stage classification Prognosis Esophagogastric junction cancer Neoadjuvant chemotherapy Siewert type

Breaking the Fe_(3)O_(4)-wrapped copper microstructure to enhance copper-slag separation

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2312-2325页

作者： Xiaopeng Chi Haoyu Liu Jun Xia hang Chen Xiangtao yu Wei Weng Shuiping zhong zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China Fujian Key Laboratory of Green Extraction and High-Value Utilization of New Energy Metals Fuzhou UniversityFuzhou 350108China zijin Mining Group Co. Ltd.Longyan 364200China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of copper ***,the commercial powdery pyrite or anthracite is replaced with pyrite-anthracite pellets as the reductants to remove a large amount of Fe_(3)O_(4)particles in the molten slag,resulting in a deep fracture in the Fe_(3)O_(4)-wrapped copper microstructure and the full exposure of the copper matte *** 1wt%composite pellet is used as the reductant,the copper matte droplets are enlarged greatly from 25μm to a size observable by the naked eye,with the copper content being enriched remarkably from 1.2wt%to 4.5wt%.Density functional theory calculation results imply that the formation of the Fe_(3)O_(4)-wrapped copper structure is due to the preferential adhesion of Cu_(2)S on the Fe_(3)O_(4)particles.X-ray photoelectron spectroscopy,Fourier transform infrared spectrometer(FTIR),and Raman spectroscopy results all reveal that the high-efficiency conver-sion of Fe_(3)O_(4)to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network *** a consequence,the settling of copper matte droplets is enhanced due to the lowered slag viscosity,contributing to the high efficiency of copper-slag separation for copper *** results provide new insights into the enhanced in-situ enrichment of copper from mol-ten slag.

关键词： pyrometallurgical smelting process slag cleaning reductants copper matte

Experimental Study on the Sinking and Leveling of A Large-Capacity Offshore Wind Turbine Five-Bucket Foundation in Sand

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China Ocean Engineering 2024年第4期38卷 586-601页

作者： LIAN Ji-jian zHU hang GUO Yao-hua WANG Hai-jun yu Tong-shun State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Tianjin University of Technology Tianjin 300384China College of Engineering Ocean University of ChinaQingdao 266100China

As offshore wind farms expand into deeper and farther ocean regions and the unit capacity of offshore wind turbines(OWTs)increases,there is a pressing need for a new foundation structure that can accommodate deep-sea conditions and support large capacities while maintaining economical and *** meet this goal of integrated transportation and one-step installation,a novel five-bucket jacket foundation(FBJF),with its suction installation and leveling methods in sand,has been proposed,analyzed and experimentally ***,seepage failure experiments of the FBJF at various depths were conducted,and a formula for calculating the critical suction of seepage failure suitable for the FBJF in sand was chosen and recommended for use with a range of values for the permeability coefficient ***,through leveling experiments of the FBJF at different depths,the maximum adjustable leveling angle during the sinking process was defined using seepage failure and the adjustable leveling angle of the foundation as control *** leveling control strategies were proposed and ***,an automatic sinking and leveling control system for the FBJF was developed and experimentally verified for feasibility.

关键词： offshore wind turbine(OWT) bucket foundation seepage failure suction installation

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-zhi Pan yu-hang Guo Qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

Unveiling the Contribution of Lactic Acid to the Passivation Behavior of Ti-6Al-4V Fabricated by Laser Powder Bed Fusion in Hank’s Solution

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 102-118页

作者： yu-hang Chu Liang-yu Chen Bo-yuan Qin Wenbin Gao Fanmin Shang Hong-yu Yang Lina zhang Peng Qin Lai-Chang zhang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100China Foshan(Southern China)Institute for New Materials Foshan528200China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

In actual physiological environments,bacteria can activate the immune system and release lactic ***,the detailed contribution of lactic acid to the passivation behavior of titanium(Ti)alloys is still *** current work investigated the in vitro passivation behavior of Ti-6Al-4V(TC4)alloys fabricated by laser powder bed fusion in Hank's solution with and without adding lactic *** methods,inductively coupled plasma atomic emission spectrometer,and X-ray photoelectron spectroscopy were jointly *** lactic acid decreases the corrosion resistance of samples by degrading the formed passive *** film formed in the(lactic acid)-containing solution exhibits a higher level of oxygen vacancies and a lower thickness,attributed to the suppressed formation of Ti^(4+)transformed from Ti^(3+)and Ti^(2+).Moreover,the presence of lactic acid would increase the open circuit potential,relieve the ions release,and hinder the deposition of calcium phosphates within 24 h immersion.

关键词： Titanium alloy Corrosion behavior Passive film Lactic acid Laser powder bed fusion

A survey on model-based reinforcement learning

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Science China(Information Sciences) 2024年第2期67卷 59-84页

作者： Fan-Ming LUO Tian XU hang LAI Xiong-Hui CHEN Weinan zhang Yang yu National Key Laboratory for Novel Software Technology Nanjing University Polixir. ai Department of Computer Science and Engineering Shanghai Jiao Tong University

Reinforcement learning(RL) interacts with the environment to solve sequential decision-making problems via a trial-and-error approach. Errors are always undesirable in real-world applications, even though RL excels at playing complex video games that permit several trial-and-error attempts. To improve sample efficiency and thus reduce errors, model-based reinforcement learning(MBRL) is believed to be a promising direction, as it constructs environment models in which trial-and-errors can occur without incurring actual costs. In this survey, we investigate MBRL with a particular focus on the recent advancements in deep RL. There is a generalization error between the learned model of a non-tabular environment and the actual environment. Consequently, it is crucial to analyze the disparity between policy training in the environment model and that in the actual environment, guiding algorithm design for improved model learning, model utilization, and policy training. In addition, we discuss the recent developments of model-based techniques in other forms of RL, such as offline RL, goal-conditioned RL, multi-agent RL, and meta-RL. Furthermore,we discuss the applicability and benefits of MBRL for real-world tasks. Finally, this survey concludes with a discussion of the promising future development prospects for MBRL. We believe that MBRL has great unrealized potential and benefits in real-world applications, and we hope this survey will encourage additional research on MBRL.

关键词： reinforcement learning model-based reinforcement learning planning model learning model learning with reduced error model usage