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Tungsten 2024年第03期6卷 621-632页

作者： Jing Zhao Lei Gao Jian-Jun Zhao Wei Wei hui-qin yun Ru Xing Huai-Jin Ma Xiang Jin Luo-Meng Chao School of Physical Science and Technology Key Laboratory of Magnetism and Magnetic Materials for Higher Education in Inner Mongolia Autonomous Region Baotou Teachers' College National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths School of Physics and Electronic Information Inner Mongolia Normal University College of Science Inner Mongolia University of Science and Technology

In this study,a novel method is proposed for producing perovskite rare-earth manganese oxide magnetic refrigeration materials that exhibit superior properties compared to similar *** maximum magnetic entropy change values for this sample are 1.44 and 3.75 J·kg-1·K-1for magnetic fields of 2 and 7 T,***,its relative cooling power has been calculated to be 101.96 and 404.78 J·kg-1,indicating good *** results were obtained using the sample synthesized under a pressure of 4 GPa,and the sample has undergone a second phase *** critical behavior of the sample fits well with the mean field *** different magnetic fields,there is a significant overlap between the values of the maximum magnetic entropy change and the temperature-averaged entropy change,indicating that the refrigeration performance of the sample after high pressure can approach its maximum capability.

关键词： High-pressure synthesis Magnetocaloric effect Relative cooling power Magnetic phase transition

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan hui-yun Hao qin Wu yun-qing Liu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong hui Li Ya‑qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic *** aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese *** A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in *** and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were *** The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒*** apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th *** total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,*** total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural *** The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒*** attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Associative Tasks Computing Offloading Scheme in Internet of Medical Things with Deep Reinforcement Learning

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China Communications 2024年第4期21卷 38-52页

作者： Jiang Fan qin Junwei Liu Lei Tian hui School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The Internet of Medical Things(Io MT) is regarded as a critical technology for intelligent healthcare in the foreseeable 6G era. Nevertheless, due to the limited computing power capability of edge devices and task-related coupling relationships, Io MT faces unprecedented challenges. Considering the associative connections among tasks, this paper proposes a computing offloading policy for multiple-user devices(UDs) considering device-to-device(D2D) communication and a multi-access edge computing(MEC)technique under the scenario of Io MT. Specifically,to minimize the total delay and energy consumption concerning the requirement of Io MT, we first analyze and model the detailed local execution, MEC execution, D2D execution, and associated tasks offloading exchange model. Consequently, the associated tasks’ offloading scheme of multi-UDs is formulated as a mixed-integer nonconvex optimization problem. Considering the advantages of deep reinforcement learning(DRL) in processing tasks related to coupling relationships, a Double DQN based associative tasks computing offloading(DDATO) algorithm is then proposed to obtain the optimal solution, which can make the best offloading decision under the condition that tasks of UDs are associative. Furthermore, to reduce the complexity of the DDATO algorithm, the cacheaided procedure is intentionally introduced before the data training process. This avoids redundant offloading and computing procedures concerning tasks that previously have already been cached by other UDs. In addition, we use a dynamic ε-greedy strategy in the action selection section of the algorithm, thus preventing the algorithm from falling into a locally optimal solution. Simulation results demonstrate that compared with other existing methods for associative task models concerning different structures in the Io MT network, the proposed algorithm can lower the total cost more effectively and efficiently while also providing a tradeoff between delay and energy co

关键词： associative tasks cache-aided procedure double deep Q-network Internet of Medical Things(IoMT) multi-access edge computing(MEC)

Regulation of solvation structure and the cooperation environment of potassium bonds for wider-temperature adaptive potassium storage

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Rare Metals 2024年第4期43卷 1610-1621页

作者： Bing-Bing Liu Yi-hui Liu You-Bin Zhang Zhen-Guo Qi Guo-hui qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China Shandong Synergetic Innovation Center of Ecological and Chemical Engineering Qingdao266042China

Antimony selenide(Sb_(2)Se_(3))is one of the perspective candidates for potassium-ion batteries due to its advanced virtues stem including featured high capacity,fertile reserves and the relative narrow band *** the unique advantages,it is still plagued by the unstable interface compatibility and poor wider-temperature *** optimization of microstructure and the construction of inorganic-organic hybrids with a low desolvation barrier and rapid kinetics behaviors are efficient to address these *** Sb_(2)Se_(3)nanorods enclosed by the S-doped carbon layer(SC),further crosslinked by the poly(N-isopropylacrylamide)(PM)film(PM@Sb_(2)Se_(3)@SC),were artificially fabricated,and it displays the enrichment ion aggregated model as well as contacted ion pair state,the well-tailored cooperation environment of potassium bonds,assuring a homogeneous potassium deposition and an excellent widertemperature *** complicated experimental studies and theoretical calculations authenticate the synergistic effects of geometric conformation and compositional design for the tremendously enhanced potassium ***,the full device over PM@Sb_(2)Se_(3)@SC anode and the potassium Prussian blue cathode manifests impressively durable cycling life and wider-temperature adaptability,verifying the glorious contribution from the finely manipulation in solvation structure and potassium bonds to enhancing the potassium storage behaviors.

关键词： Anode Sb_(2)Se_(3) rods Interface compatibility Inorganic-organic electrode Potassium ion battery

Ligand-controlled electrochemiluminescence generation from CdSe/CdS/ZnS core/shell/shell quantum dots

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Nano Research 2024年第8期17卷 7776-7785页

作者： hui Sun Zhiyuan Cao Haiyan qin Xiaogang Peng Bin Su Key Laboratory of Excited-State Materials of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310058China

The CdSe/CdS/ZnS core/shell/shell quantum dots(QDs)with strong exciton confinement have manifested themselves as competitive light-emitting materials in electrochemiluminescence(ECL).However,cathodic ECL generation by these QDs requires the injection of electron and hole from solid electrode and electrogenerated radicals(for example SO_(4)•^(−)),which is inevitably influenced by not only the inorganic structure of QDs but also the organic ligands on the *** this work we aimed at studying the impact of surface organic ligands on ECL performance of CdSe/CdS/ZnS *** changing the surface ligand from oleate to acetate,we phenomenologically observed the positive shift of ECL onset potential by ca.200 mV and the increase of ECL intensity by~100 times,suggesting that a short ligand is more favorable for ECL *** further comprehend the ligand effect,we measured the charge injection kinetics using potential-modulated,time-resolved photoluminescence,and thinlayer spectroelectrochemistry *** electron and hole injection into QDs were found to be accelerated by 2–20 times if shortening the ligand from oleate to acetate,confirming the significant impact of surface ligands on ECL performance of *** study is expected to provide guidance on how to design surface functionalized QDs for specific applications such as ECL immunodiagnosis,photocatalysis,and photovoltaics.

关键词： electrochemiluminescence quantum dots spectroelectrochemistry surface ligands charge injection charge transfer

Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern Yangtze Block

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Acta Geochimica 2024年第4期43卷 707-718页

作者： Jun-xiao Ma Guang-shu Yang Yong-feng Yan Xiao-Fei Xu yun-hua Ren hui Zhao Xiao-jun Zheng Yuan qin Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of yunnan Non-Ferrous Metals Geological Bureau Kunming 650217China yunnan Provincial Bureau of Non-Ferrous Geology Kunming 650051China

The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the *** paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb *** schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and *** equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°*** further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde ***-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 *** with previously reported results,it is revealed that the southwestern margin of the Yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic *** may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

关键词： Southwestern Yangtze Block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism

Long non-coding RNA MALAT1 in hematological malignancies and its clinical applications

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Chinese Medical Journal 2024年第10期137卷 1151-1159页

作者： Chunlan Zhang yun qin Yu Wu Heng Xu Yang Shu Department of Hematology West China HospitalSichuan UniversityChengduSichuan 610041China Department of Radiology West China HospitalSichuan UniversityChengduSichuan 610041China Department of Laboratory Medicine/Research Center of Clinical Laboratory Medicine West China HospitalSichuan UniversityChengduSichuan 610041China Department of Biotherapy State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China Institute of General Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of General Surgery Gastric Cancer Center and Laboratory of Gastric CancerWest China HospitalSichuan UniversityChengduSichuan 610041China

Metastasis-associated lung adenocarcinoma transcript 1(MALAT1)is a well-established oncogenic long non-coding RNA,the higher expression of which is strongly correlated with cancer events such as tumorigenesis,progression,metastasis,drug resistance,and treatment outcome in solid ***,a series of studies has highlighted its potential role in hematological malignancies in terms of these *** to solid cancers,MALAT1 can regulate various target genes via sponging and epigenetic mechanisms,but the miRNAs sponged by MALAT1 differ from those identified in solid *** this review,we systematically describe the role and underlying mechanisms of MALAT1 in multiple types of hematological malignancies,including regulation of cell proliferation,metastasis,stress response,and ***,MALAT1 expression is related to poor treatment outcome and drug resistance,therefore exhibiting potential prognostic value in multiple myeloma,lymphoma,and ***,we discuss the evaluation of MALAT1 as a novel therapeutic target against cancer in preclinical studies.

关键词： Long non-coding RNA Hematological malignancies Tumorigenesis Metastasis Drug resistance Prognostic biomarker

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying qin Kai-Fan Ji hui Liu Xiao-Guang Yu yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Biopsy forceps are useful for measuring esophageal varices in vitro

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 539-545页

作者： Zhi-hui Duan Sheng-yun Zhou Endoscopy Center Xingtai People’s HospitalXingtai 054000Hebei ProvinceChina

BACKGROUND To avoid acute variceal bleeding in cirrhosis,current guidelines recommend screening for high-risk esophageal varices(EVs)by determining variceal size and identifying red wale ***,visual measurements of EV during routine endoscopy are often *** To determine whether biopsy forceps(BF)could be used as a reference to improve the accuracy of binary classification of variceal *** An in vitro self-made EV model with sizes ranging from 2 to 12 mm in diameter was *** online image-based survey comprising 11 endoscopic images of simulated EV without BF and 11 endoscopic images of EV with BF was assembled and sent to 84 *** endoscopists were blinded to the actual EV size and evaluated the 22 images in random *** The respondents included 48 academic and four private *** accuracy of EV size estimation was low in both the visual(13.81%)and BF-based(20.28%)*** use of open forceps improved the ability of the endoscopists to correctly classify the varices by size(small≤5 mm,large>5 mm)from 71.85%to 82.17%(P<0.001).CONCLUSION BF may improve the accuracy of EV size assessment,and its use in clinical practice should be investigated.

关键词： Accuracy Liver cirrhosis Esophageal varices Endoscopy Measurement