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Using an improved lightweight YOLOv8 model for real-time detection of multi-stage apple fruit in complex orchard environments

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Artificial Intelligence in Agriculture 2024年第1期11卷 70-82页

作者： Baoling Ma Zhixin Hua Yuchen wen Hongxing Deng Yongjie Zhao Liuru pu Huaibo Song College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agricultureand Rural AffairsYanglingShaanxi 712100China Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Services YanglingShaanxi 712100China

For the purpose of monitoring apple fruits effectively throughout the entire growth period in smart orchards.A lightweight model named YOLOv8n-ShuffleNetv2-Ghost-SE was *** ShuffleNetv2 basic modules and down-sampling modules were alternately connected,replacing the Backbone of YOLOv8n *** Ghost modules replaced the Conv modules and the C2fGhost modules replaced the C2f modules in the Neck part of the ***2 reduced the memory access cost through channel splitting *** Ghost module combined linear and non-linear convolutions to reduce the network computation *** Wise-IoU(WIoU)replaced the CIoU for calculating the bounding box regression loss,which dynamically adjusted the anchor box quality threshold and gradient gain allocation strategy,optimizing the size and position of predicted bounding *** Squeeze-and-Excitation(SE)was embedded in the Backbone and Neck part of YOLOv8n to enhance the representation ability of feature *** algorithm ensured high precision while having small model size and fast detection speed,which facilitated model migration and *** 9652 images validated the effectiveness of the *** YOLOv8n-ShuffleNetv2-Ghost-SE model achieved Precision of 94.1%,Recall of 82.6%,mean Average Precision of 91.4%,model size of 2.6 MB,parameters of 1.18 M,FLOPs of 3.9 G,and detection speed of 39.37 *** detection speeds on the Jetson Xavier NX development board were 3.17 *** with advanced models including Faster R-CNN,SSD,YOLOv5s,YOLOv7‑tiny,YOLOv8s,YOLOv8n,MobileNetv3_small-Faster,MobileNetv3_small-Ghost,ShuflleNetv2-Faster,ShuflleNetv2-Ghost,ShuflleNetv2-Ghost-CBAM,ShuflleNetv2-Ghost-ECA,and ShuflleNetv2-Ghost-CA demonstrated that the method achieved smaller model and faster detection *** research can provide reference for the development of smart devices in apple orchards.

关键词： Multi-stage apple fruit Deep learning Real-time detection Lightweight model

Catalase promotes whitefly adaptation to high temperature by eliminating reactive oxygen species

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Insect Science 2023年第5期30卷 1293-1308页

作者： Peng Liang Jie Ning wenlu Wang pu Zhu Lianyou Gui wen Xie Youjun Zhang Forewarning and Management of Agricultural and Forestry Pests Hubei Engineering Technology CenterInstitute of InsectCollege of AgricultureYangtze UniversityJingzhouHubei ProvinceChina Department of Plant Protection Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina Jinhua Academy of Agricultural Sciences JinhuaZhejiangChina

Thermal stress usually leads to excessive production of reactive oxygen species(ROS)in all aerobic ***(CAT)are the key antioxidant enzymes,which act as the first line of defense against ROS in the antioxidant *** highly invasive and widely distributed whitefly Bemisia tabaci MED damages plants by feeding as well as by transmitting many plant *** studies have shown that strong adaptability to high temperature helps explain the spread of MED around the ***,the mechanism underlying high temperature adaptation of this pest is not well *** this study,6 CAT genes were identified from the MED genome and transcriptome dataset,among which BtCAT1,BtCAT2,and BtCAT3 were found to be highly expressed in *** expression of BtCAT1,BtCAT2,or BtCAT3 increased with induction temperature and induction *** MED was exposed with mean high temperature(30℃ or 35℃)and a short-term extremely high temperature(39℃ or 41℃)after the silencing of BtCAT1,BtCAT2,or BtCAT3 to significantly increased ROS levels by at least 0.5 times and significantly decreased survival rate and fecundity of MED *** ROS level in the treated specimens gradually returned to a normal level after 24 h at 25℃,but the survival rate still declined *** together,our results demonstrate that CAT could help *** adapt to long-term mean high temperatures and short-term extremely high temperatures by eliminating excessive ROS.

关键词： catalase fecundity reactive oxygen species survival rate temperature adap-tation mechanism whitefly

Apple polyphenols attenuate the binding ability of angiotensin converting enzyme 2 to viral proteins: Computer simulation and in vitro experiments

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Food Bioscience 2022年第6期50卷 733-741页

作者： Yijing pu Xu He Luyao Chen Hongxuan Wang Yuxia Ma Weibo jiang College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing100083PR China Department of Nutrition and Hygiene HebeiMedical UniversityShijiazhuangChina

To investigate the effects of apple polyphenols on ACE2 and its antibody binding, computer simulation and experiments in vitro were conducted. The results of molecular docking and molecular dynamics showed that apple polyphenols had a good binding effect on RBD and RBD-ACE2 complex. Fluorescence analysis exhibited that the three main apple polyphenols had a fluorescence quenching effect on the ACE2 antibodies, and the quenching mechanism was static. The results of the circular dichroism experiment suggested that apple polyphenols could change the secondary structure of the ACE2 antibodies. Western blot results displayed that apple polyphenols inhibited the binding of ACE2 and its antibodies. This study confirmed that apple polyphenols could bind ACE2 antibodies in vitro. Therefore, it is speculated that apple polyphenols have similar effects on a class of proteins with similar ACE2 recognition sites, which may potentially inhibit viral protein and ACE2 recognition, thus preventing viruses from entering host cells.

关键词： Apple polyphenols RBD protein ACE2 antibodies Molecular docking simulation Molecular dynamics simulation

Characterization of endogenous nucleic acids that bind to NgAgo in Natronobacterium gregoryi sp2 cells

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BIOCELL 2022年第2期46卷 547-557页

作者： LIXU jiang LIN NING CHUNCHAO pu ZIXIN WANG BIFANG HE JIAN HUANG School of Life Science and Technology University of Electronic Science and Technology of ChinaChengdu611731China School of Healthcare Technology Chengdu Neusoft UniversityChengdu611844China School of Medicine Guizhou UniversityGuiyang550025China

As nucleic acid-guided endonucleases,some prokaryotic Argonautes have been used as programmable *** gregoryi Argonaute(NgAgo)has also been proposed for gene editing,but this remains very *** now,the endogenous nucleic acids that bind to NgAgo in Natronobacterium gregoryi sp2(*** sp2)have not been *** expressed the conserved PIWI domain of NgAgo and used it to induce anti-PIWI *** also cultured the *** sp2 strain and performed immunoprecipitation,chromatin immunoprecipitation(ChIP),and RNA immunoprecipitation(RIP)*** nucleic acids that endogenously bound NgAgo in *** sp2 cells were sequenced and *** results showed that NgAgo endogenously bound RNA rather than ***-associated RNAs were mainly transcripts of genes that encoded tRNA,transcriptional regulators,RNA polymerases,and RNA-binding *** mainly binds to the transcripts inside genes or in their upstream ***,the top enriched motif of peaks was the same as that of miR-1289,suggesting that NgAgo may regulate gene expression *** enrichment analysis showed that the peak-associated genes were enriched in transmembrane transport *** results revealed that NgAgo binds RNA and may function in post-transcriptional regulation in vivo.

关键词： NgAgo PIWI Immunoprecipitation ChIP-seq RIP-seq Post-transcriptional regulation

Formation mechanism of the Lidang circular structure in the Guangxi Province

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Earth and Planetary Physics 2019年第4期3卷 298-304页

作者： Pan Yan ZhiYong Xiao YiZhen Ma YiChen Wang jiang pu Planetary Science Institute School of Earth Sciences China University of Geosciences (Wuhan) Wuhan 430074 China 2State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and Technology Macao 999078 China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Beijing 100864 China

The Lidang circular structure in the center of the Guangxi Province is about 8 km in diameter. This structure appears as an abnormal shallow depression that has disturbed the rather harmonic regional joint systems. Its unique occurrence in the whole region, the circular morphology, negative topography, and the spatial distribution of interior and exterior strata are all consistent with those of impact craters that are formed by asteroidal or cometary collision. To test the impact hypothesis, we carried out both field investigation and remote sensing study of this structure. Regional geological history suggests that if the impact hypothesis were correct, the impact event should have occurred at or after the Early Permian. Field investigation found that the strata inside and outside the crater are dominated by parallel stacks of Lower and Upper Permian limestone that have various thicknesses and different mud contents. The layers of limestone within and outside the circular structure have identical attitudes;no structural disturbances were visible in the outcrops. Field investigations provide conclusive evidence against the impact cratering hypothesis. A high-resolution digital elevation model shows that the spatial distribution of rounded mountains within the structure is controlled by faint but continual extension of joints, suggesting that the crater interior has gone through a much higher degree of erosion. Therefore, regional joints that had once existed within the crater are preserved less well than exterior terrains, forming the abruptly disrupted circular depression. Differential erosion, as the possible formation mechanism of the Lidang structure, is consistent with the different mud contents found between the interior and exterior limestone. The circular outline of this structure may correspond to the shape of the original deposition basin. In conclusion, the Lidang circular structure is a polje formed by karstification, not an astrobleme.

关键词： impact crater impact cratering geomorphology karst Guangxi

Water molecule-induced hydrogen bonding between cellulose nanofibers toward highly strong and tough materials from wood aerogel

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Chinese Chemical Letters 2021年第10期32卷 3105-3108页

作者： Xiaoshuai Han Zhenxing Wang Linhu Ding Lian Chen Feng Wang Junwen pu Shaohua jiang Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China MOE Engineering Research Center of Forestry Biomass Materials and Bioenergy Beijing Forestry UniversityBeijing 100083China

Lightweight,highly strong and bio-based structural materials remain a long-lasting ***,inspired by nacre,a lightweight and high mechanical performance cellulosic material was fabricated via a facile and effective top-down approach and the resulting material has a high tensile strength of149.21 MPa and toughness of 1.91 MJ/m^(3).More specifically,the natural balsawood(NW) was subjected to a simple chemical treatment,removing most lignin and partial hemicellulose,follow by freeze-drying,forming wood aerogel(WA).The delignification process produced many pores and exposed numerous aligned cellulose ***,the WA absorbed a quantity of moisture and was directly densified to form above high-performance cellulosic *** treatment imitates highly ordered"brick-and-mortar" arrangement of nacre,in which water molecules plays the role of mortar and cellulose nanofibrils make the brick *** lightweight and good mechanical properties make this material promising for new energy car,aerospace,*** paper also explains the strengthening mechanism for making biomimetic materials by water molecules-induced hydrogen bonding and will open a new path for designing high-performance bio-based structural materials.

关键词： Wood aerogel Cellulose nanofibers Water molecules Hydrogen bonding Strength and toughness

PREDICTION OF MAXIMUM SCOUR DEPTH AROUND LARGE DIAMETER CYLINDER UNDER THE EFFECTS OF BOTH WAVE AND CURRENT

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Journal of Hydrodynamics 2005年第1期17卷 74-79页

作者： LILin-pu CUILi SchoolofCivilandHydraulicEngineering~DalianUniversityofTechnology Dalian116024china

Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result of tests, an analysis was made on all the factors influencing the scour. The results shows that for the seabed with relative fine grains in shallow water (0.07

关键词： offshore engineering the effects of both wave and current large diameter cylinder local scour

A preliminary experimental investigation on the biotribocorrosion of a metal-on-polyethylene hip prosthesis in a hip simulator

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Friction 2023年第6期11卷 1094-1106页

作者： Shu YANG Jian pu Xiaogang ZHANG Yali ZHANG wen CUI Fengbao XIE Weiping LU Qin TAN Zhongmin JIN Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu610031China Beijing Chunlizhengda Medical Instruments Co. Ltd.Beijing101100China School of Mechanical Engineering University of LeedsLeedsLS29JTUK

Corrosion at the taper/trunnion interface of total hip replacement(THR)often results in severe ***,the underlying mechanisms of biotribocorrosion at the taper/trunnion interface during the long-term walking gait cycles remain to be fully *** this study,a hip joint simulator was therefore instrumented with an electrochemical cell for in-situ monitoring of the tribocorrosion evolution in a metal-on-polyethylene(MoP)THR during a typical long-term walking *** addition,the biotribocorrosion mechanism was investigated via surface and chemical *** experimental results confirmed that the taper/trunnion interface dominated the contemporary MoP hip joint *** cyclic variations in the open circuit potential(OCP)were observed throughout the long-term electrochemical measurements,attributed to the formation and disruption of the adsorbed protein *** corrosion exhibited an initial increase at each period,peaking at approximately 0.125 million cycles,followed by a subsequent gradual *** and chemical analyses revealed the formation of a tribochemical reaction layer(tribolayer)on the worn surface of the taper/trunnion *** surface/chemical characterizations and the electrochemical measurements indicated that the adhesion force of the adsorbed protein layer was weaker than that of the *** contrast,the opposite was true for the corrosion *** on the observations from this study,the tribocorrosion mechanism of the taper/trunnion interface under the long-term walking gait cycles is deduced.

关键词： biotribocorrosion metal-on-polyethylene(MoP) adsorbed protein layer total hip replacement(THR)

Configuration and Spin Assignments of Yrast Band for Doubly Odd Nucleus ^(122)Cs

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Chinese Physics Letters 1998年第7期15卷 480-482页

作者： pu Yun-wei wen Jia-yan ZHU Shun-quan ZHENG Ren-rong Department of Physics Southwest Normal UniversityChongqing 400715

Energy spectrum of yrast band for ^(122)Cs is studied by using particle-rotor model(PRM)of odd-odd nuclei,in which special attention is paid to the model basis accounting for the effect of the instabilityγvibration perturbation around axial *** order to check the assignments of this band,two calculation schemes are put into *** first one is for previousπh11/2 vg7/2 configuration with bandhead spin I_(0)=(6^(-))which was obtained from cranked shell model(CSM)calculation,and the other one is forπh_(11/2) vh_(11/2) configuration with I_(0)=(9^(+))supported by the systematic analyses of experimental data.A qualitative comparison between the present PRM calculation and that of CSM has also been *** results indicate that,rather thanπh_(11/2) vg_(7/2) I_(0)=(6^(-)),πh_(11/2) vh_(11/2) with I_(0)=(9^(+))is a more reasonable assignment to the yrast band in ^(122)Cs.

关键词： assignment Configuration