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A Galaxy Image Augmentation Method Based on Few-shot Learning and Generative Adversarial Networks

Research in Astronomy and Astrophysics 2024年第3期24卷 180-193页

作者： Yiqi yao Jinqu Zhang Ping du Shuyu Dong School of Artificial Intelligence South China Normal UniversityFoshan 528225China School of Computer Science South China Normal UniversityGuangzhou 510631China Guangdong Construction Vocational Technology Institute Guangzhou 511500China

Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the machine learning models.Therefore this article proposes an image data augmentation method that combines few-shot learning and generative adversarial networks.The Galaxy10 DECaLs data set is selected for the experiments with consistency,variance,and augmentation effects being evaluated.Three popular networks,including AlexNet,VGG,and ResNet,are used as examples to study the effectiveness of different augmentation methods on galaxy morphology classifications.Experiment results show that the proposed method can generate galaxy images and can be used for expanding the classification model’s training set.According to comparative studies,the best enhancement effect on model performance is obtained by generating a data set that is 0.5–1 time larger than the original data set.Meanwhile,different augmentation strategies have considerably varied effects on different types of galaxies.FSL-GAN achieved the best classification performance on the ResNet network for In-between Round Smooth Galaxies and Unbarred Loose Spiral Galaxies,with F1 Scores of 89.54%and 63.18%,respectively.Experimental comparison reveals that various data augmentation techniques have varied effects on different categories of galaxy morphology and machine learning models.Finally,the best augmentation strategies for each galaxy category are suggested.

关键词： techniques image processing-galaxies structure-galaxies general

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Sexual Dimorphism and Female Reproductive Characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China

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Asian Herpetological Research 2024年第1期15卷 49-58页

作者： Yu du Xiaming ZHU Chixian LIN Yuntao yao Xiang JI Hainan Key Laboratory for Herpetological Research College of Fisheries and Life SciencesHainan Tropical Ocean UniversitySanya 572022HainanChina Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection College of Life and Environmental SciencesWenzhou UniversityWenzhou 325035ZhejiangChina Institute for Eco-environmental Research of Sanyang Wetland Wenzhou UniversityWenzhou 325014ZhejiangChina

We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3–6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus.

关键词： fecundity morphology offspring size-number trade-off reproduction scincidae sexual dimorphism

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Combining graph neural network with deep reinforcement learning for resource allocation in computing force networks

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 701-712页

作者： Xueying HAN Mingxi XIE Ke YU Xiaohong HUANG Zongpeng du Huijuan yao School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Infrastructure Network Technology Research China Mobile Research InstituteBeijing 100032China

Fueled by the explosive growth of ultra-low-latency and real-time applications with specific computing and network performance requirements,the computing force network(CFN)has become a hot research subject.The primary CFN challenge is to leverage network resources and computing resources.Although recent advances in deep reinforcement learning(DRL)have brought significant improvement in network optimization,these methods still suffer from topology changes and fail to generalize for those topologies not seen in training.This paper proposes a graph neural network(GNN)based DRL framework to accommodate network trafic and computing resources jointly and efficiently.By taking advantage of the generalization capability in GNN,the proposed method can operate over variable topologies and obtain higher performance than the other DRL methods.

关键词： Computing force network Routing optimization Deep learning Graph neural network Resource allocation

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Multi-Material Topology Optimization of 2D Structures Using Convolutional Neural Networks

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1919-1947页

作者： Jiaxiang Luo Weien Zhou Bingxiao du Daokui Li Wen yao College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China Defense Innovation Institute Chinese Academy of Military ScienceBeijing100071China Intelligent Game and Decision Laboratory Chinese Academy of Military ScienceBeijing100071China

In recent years,there has been significant research on the application of deep learning(DL)in topology optimization(TO)to accelerate structural design.However,these methods have primarily focused on solving binary TO problems,and effective solutions for multi-material topology optimization(MMTO)which requires a lot of computing resources are still lacking.Therefore,this paper proposes the framework of multiphase topology optimization using deep learning to accelerate MMTO design.The framework employs convolutional neural network(CNN)to construct a surrogate model for solving MMTO,and the obtained surrogate model can rapidly generate multi-material structure topologies in negligible time without any iterations.The performance evaluation results show that the proposed method not only outputs multi-material topologies with clear material boundary but also reduces the calculation cost with high prediction accuracy.Additionally,in order to find a more reasonable modeling method for MMTO,this paper studies the characteristics of surrogate modeling as regression task and classification task.Through the training of 297 models,our findings show that the regression task yields slightly better results than the classification task in most cases.Furthermore,The results indicate that the prediction accuracy is primarily influenced by factors such as the TO problem,material category,and data scale.Conversely,factors such as the domain size and the material property have minimal impact on the accuracy.

关键词： Multi-material topology optimization convolutional neural networks deep learning finite element analysis

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Amide naphthotubes:Biomimetic macrocycles for selective molecular recognition

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Chinese Chemical Letters 2024年第4期35卷 124-131页

作者： Cheng-Da Zhao Huan yao Shi-yao Li Fangfang du Li-Li Wang Liu-Pan Yang School of Pharmaceutical Science Postdoctoral Research Station of Basic MedicineHengyang Medical SchoolUniversity of South ChinaHengyang 421001China

Selective molecular recognition in water is routine for bioreceptors,but remains challenging for synthetic hosts.This is principally because noncovalent interactions are usually less efficient in aqueous environments.By mimicking the cavity feature of bioreceptors,Prof.Wei Jiang proposed and clarified the concept of“endo-functionalized cavity”.Through situating polar binding sites into a deep hydrophobic cavity,we designed and synthesized several macrocyclic hosts,among which amide naphthotubes are the most representative.The hosts can selectively recognize various polar molecules including organic micropollutants,drug molecules,and chiral molecules in water by employing the hydrophobic effect and shielded hydrogen bonding.In addition,these biomimetic hosts have been applied in spectroscopic analysis,adsorptive separation and self-assembly.In this review,we provide an overview of recent advances on amide naphthotubes with special emphasis on the efforts of Jiang's group.We are convinced that these biomimetic macrocycles will make further contributions to supramolecular chemistry and beyond.

关键词： Molecular recognition Supramolecular chemistry Amide naphthotube Endo-functionalized cavity Biomimetic macrocycle

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A Confined Two-peaked Solar Flare Observed by EAST and SDO

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Research in Astronomy and Astrophysics 2024年第4期24卷 71-83页

作者： Liang Zhang Ruisheng Zheng Zhike Xue Changhui Rao Qing Lin Zhimao du Jiawen yao Libo Zhong yao Chen Institute of Space Sciences Shandong UniversityWeihai 264209China Yunnan Key Laboratory of the Solar physics and Space Science Kunming 650011China Institute of Frontier and Interdisciplinary Science.Shandong University Qingdao266237China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China National Laboratory on Adaptive Optics Chengdu610209China University of Chinese Academy of Sciences Beijing 100049China Shanghai Astronomy Museum Shanghai201306China

The solar flare is one of the most violent explosions,and can disturb the near-Earth space weather.Except for commonly single-peaked solar flares in soft X-ray,some special flares show intriguing a two-peak feature that is deserved much more attentions.Here,we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics Observatory.Before the flare,a magnetic flux rope(MFR)formed through partially tether-cutting reconnection between two sheared arches.The flare occurred after the MFR eruption that was confined by the overlying strong field.Interestingly,a small underlying filament immediately erupted,which was possibly destabilized by the flare ribbon.The successive eruptions were confirmed by the analysis of the emission measure and the reconnection fluxes.Therefore,we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.

关键词： Sun:activity Sun:corona Sun:flares Sun:magnetic fields Sun:filaments prominences Online material:animations

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Efficacy and safety of clarithromycin for patients with sepsis or septic shock:a systematic review and meta-analysis

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Emergency and Critical Care Medicine 2024年第2期4卷 90-96页

作者： Pengyue Zhao Renqi yao Jiaqi Yang Wei Wen Yongming yao Xiaohui du Department of General Surgery First Medical Center of the Chinese PLA General HospitalBeijingChina Translational Medicine Research Center Medical Innovation Research Division and Fourth Medical Center of the Chinese PLA General HospitalBeijingChina Department of Burn Surgery the First Affiliated Hospital of Naval Medical UniversityShanghaiChina Department of General Surgery Hainan Hospital of Chinese PLA General HospitalSanyaHainanChina.

Background:Clarithromycin exerts an immunomodulatory role in several human diseases.However,whether this effect improves the prognosis in patients with sepsis remains controversial,and higher levels of clinical evidence are urgently needed.To the best of our knowledge,no meta-analysis to date has reported the clinical efficacy and safety of clarithromycin in sepsis.Methods:A comprehensive literature search of PubMed,EMBASE,and the Cochrane Library was conducted up to December 31,2022.Only randomized controlled trials comparing the clinical efficacy and safety of clarithromycin with controls among patients with sepsis or septic shock were included.Data were pooled by applying a fixed-effects model and a relative risk(RR)estimate with 95%confidence intervals(CIs)using Review Manager(version 5.3;Cochrane Collaboration,Copenhagen,Denmark).Results:Three randomized controlled trials involving a total of 910 patients were included.The pooled results confirmed that clarithromycin had no beneficial effect on progression to multiple organ dysfunction syndrome(RR:1.51;95%CI:1.02-2.25;P=0.04;I^(2)=0%),28-day mortality(RR:1.09;95%CI:0.87-1.36;P=0.46;I^(2)=0%),and 90-day mortality(RR:0.86;95%CI:0.71-1.03;P=0.10;I^(2)=81%)in patients with sepsis or septic shock.Moreover,there was no difference in other serious adverse events between patients who received clarithromycin and those in the control group(RR:1.02;95%CI:0.87-1.19;P=0.83;I^(2)=18%).Conclusion:Our meta-analysis did not reveal an improvement to short-term outcomes in patients with sepsis treated with clarithromycin.However,administration of clarithromycin did not increase the risk of adverse events.

关键词： Clarithromycin Meta-analysis Outcomes Sepsis Septic shock

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Ultra-highly selective recognition of nucleosides over nucleotides by rational modification of tetralactam macrocycle and its application in enzyme assay

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Chinese Chemical Letters 2024年第6期35卷 274-278页

作者： Huan yao Jian Qin Yan-Fang Wang Song-Meng Wang Liu-Huan Yi Shi-yao Li Fangfang du Liu-Pan Yang Li-Li Wang School of Pharmaceutical Science Postdoctoral Research Station of Basic MedicineHengyang Medical SchoolUniversity of South ChinaHengyang 421001China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

Artificial macrocycle with high binding selectivity in water is often challenging but urgently needed in various research and application areas.Herein,we report a new water-soluble biomimetic tetralactam macrocycle and realize the ultra-high selectivity to nucleosides over corresponding monophosphate nucleotides by rational modification.The introduction of charged groups at the periphery of endofunctionalized cavity makes the selectivity(guanosine to guanosine 5-monophosphate)increase remarkably from 100 to 1119.Based on the ultra-high selectivity of biomimetic tetralactam macrocycle,the sensitive CD73 enzyme activity assay was then achieved through product-selective fluorescence indicator displacement assay.Furthermore,the capability of the proposed method for inhibitor screening was successfully displayed.

关键词： Rational modification Biomimetic macrocycle Ultra-high selectivity Enzyme assay

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A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band mode.This topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency points.Consequently,it can be applied to transmitters that are excited by broadband signals.In particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design idea.Its saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 MHz.These results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

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Persistent greening against drying in northeast Asian semiarid grasslands:Asymmetrical responses of direct and legacy effects to intensified drought

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Advances in Climate Change Research 2024年第1期15卷 9-20页

作者： Yu-Tong MA Hai-Shan CHEN yao-Ming SONG Bo-Tao ZHOU Shan-Lei SUN Xin-Guan du Yue SUN Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

Despite experiencing a decadal shift towards drought conditions at the end of the 2Oth century,semiarid grasslands in northeast Asia(NEA)exhibited an evident greening trend from 1982 to 2020.However,the mechanism behind this phenomenon remains unclear.Hence,we analysed the interdecadal changes in vegetation response to drought on the basis of the standardised precipitation evapotranspiration index(SPEI)and Global Inventory Modelling and Mapping Studies LAI4g datasets,with an emphasis on the differences between direct and legacy effects(as measured by resilience),to explore the mechanism of persistent grassland greening.Results revealed that during the post-drought shift period(2000-2020),the sudden decrease in the water content of the intermediate soil layer triggered an intensified vegetation response to drought.Specifically,although direct effects and resilience were amplified,they exhibited asymmetric changes.Resilience was stronger than direct effects,and this difference increased with increasing drought(drought recovery)levels.These combined effects may account for persistent greening against intensified drying in the semiarid grasslands in NEA.Given the projected exacerbation of future droughts,this study holds notable importance for comprehending the long-term change dynamics of dryland ecosystems.

关键词： Semiarid grassland Drought decadal shift Direct effect Legacy effect(resilience) Northeast Asia

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