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Canopy deposition characteristics of different orchard pesticide dose models

International Journal of Agricultural and Biological Engineering 2023年第3期16卷 1-6页

作者： Qingqing Zhou Xinyu Xue Chen Chen Chen Cai Yuxuan Jiao Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsJiangsu UniversityNanjing 210014China

Pesticide dose model based on canopy characteristics is the guidance basis for spray parameters adjustment.In this study,the calculation formula and canopy deposition characteristics of leaf wall area(LWA)model,tree row volume(TRV)model,and optimal coverage method(OCM)model were described and compared.A tower air-assisted spray test bench was applied to provide fine quality droplets,suitable wind speed and demand spray flow rate for corresponding models,an electric flat board vehicle was applied to drive tree in a straight line to simulate the sprayer movement speed,and droplet deposition distribution were tested in different leaf area density canopy.The results showed that the spray flow rates of three pesticide dose models decreased gradually.LWA model was only related to canopy height,TRV model was related to canopy height and canopy diameter,while OCM model was related to canopy height,canopy diameter and leaf area density.Whether dense or sparse canopy,TRV model basically satisfied the requirement of coverage rate greater than 33%in the entire canopy,OCM model met the requirement of coverage density greater than 70 droplets/cm^(2).However,LWA model,for dense canopy,unit area deposition of outermost leaves near sprayer was 3.6 times of the apple leaf maximum retention,which had a high loss risk;for sparse canopy,penetration rates of outermost leaves far away sprayer,that is,the drift rate was 21.4%.The discussion leads to the conclusion that for conventional spraying,TRV model represented a substantial improvement compared to LWA model,and OCM model was a reasonable low volume spraying model.This study provides a reference to different growth seasons spray amount adjustments in orchard.

关键词： orchard plant protection pesticide dose model leaf wall area tree row volume optimal coverage method

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Vicinal hydroxyl group-inspired selective oxidation of glycerol to glyceric acid on hydroxyapatite supported Pd catalyst

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Green Energy & Environment 2022年第4期7卷 691-703页

作者： Difan Li Xiuge Zhao Qingqing Zhou Bingjie Ding Anna Zheng Qingpo Peng Zhenshan Hou Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Selective oxidation of glycerol provides a feasible route towards the sustainable synthesis of high value-added chemicals.Herein,the hydroxyapatite(HAP)supported palladium(Pd)species were fabricated by impregnation and subsequent calcination.The as-obtained heterogeneous Pd catalyst afforded not only excellent selectivity to glyceric acid(GLA)up to 90%with 59%conversion of glycerol but also good recyclability by using molecular oxygen as an oxidant under mild conditions.The characterization of catalysts indicated that both the surface basicity and Pd sites on the catalyst played a crucial role in promoting glycerol oxidation.Notably,it demonstrated that the presence of the vicinal hydroxyl group of glycerol molecule can assist the oxidation reaction via forming a coordination between the vicinal hydroxyl group and Ca^(2+) sites on HAP-derived catalysts.In this catalytic process,the secondary hydroxyl of glycerol kept untouched and the primary hydroxyl of glycerol was converted into carboxyl group,while the Pd species acted as active centers for cooperatively promoting the subsequent oxidation to generate GLA.Additionally,this catalytic system can be extended widely for the oxidative conversion of other vicinal diols into the corresponding a-hydroxycarboxylic acids selectively.Isotope labeling experiment using H_(2)^(18)O confirmed that H_(2)O not only acted as solvent but also was involved in the catalytic cycles.On the basis of the results,a possible reaction mechanism has been proposed.The HAP-supported Pd catalytic system has been shown to serve as an effective approach for the upgrading of bio-derived vicinal diols to high value-added chemicals.

关键词： Hydroxyapatite Palladium Glycerol oxidation Glyceric acid Vicinal hydroxyl group

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Preparation of Peptide Selenoesters from Their Corresponding Acyl Hydrazides

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Chinese Journal of Chemistry 2021年第7期39卷 1861-1866页

作者： Yunxue Li Jiazhi Liu Qingqing Zhou Jie Zhao Ping Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical EngineeringFrontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai200240 China

Main observation and conclusion Selenoesters are useful substitutes for traditional thioesters in protein ligation chemistry due to their high reactivity in the trans-thio/selenoesterification reaction.However,existing synthetic routes to access peptide selenoester require a selenoesterification reaction between a selenide and a protected peptide with a free carboxylate at the C-terminus.

关键词： Peptides Hydrazide Selenium Synthetic methods One-pot ligation

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Ultraviolet photodetectors based on ferroelectric depolarization field

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Journal of Energy Chemistry 2023年第2期77卷 487-498,I0013页

作者： Xiaoyu zhou qingqing Ke Silin Tang Jilong Luo Zihan Lu School of Microelectronics Science and Technology Sun Yat-sen UniversityZhuhai 519082GuangdongChina Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen UniversityZhuhai 519082GuangdongChina

Ultraviolet(UV)photodetectors are extensively adopted in the fields of the Internet of Things,optical communications and imaging.Nowadays,with broadening the application scope of UV photodetectors,developing integrated devices with more functionalities rather than basic photo-detecting ability are highly required and have been triggered ever-growing interest in scientific and industrial communities.Ferroelectric thin films have become a potential candidate in the field of UV detection due to their wide bandgap and unique photovoltaic characteristics.Additionally,ferroelectric thin films perform excellent dielectric,piezoelectric,pyroelectric,acousto-optic effects,etc.,which can satisfy the demand for the diversified development of UV detectors.In this review,according to the different roles of ferroelectric thin films in the device,the UV photodetectors based on ferroelectric films are classified into ferroelectric depolarization field driven type,ferroelectric depolarization field and built-in electric field co-driven type,and ferroelectric field enhanced type.These three types of ferroelectric UV photodetectors have great potential and are expected to promote the development of a new generation of UV detection technology.At the end of the paper,the advantages and challenges of three types of ferroelectric UV photodetectors are summarized,and the possible development direction in the future is proposed.

关键词： UV photodetector Ferroelectric Thin film Depolarization field Built-in electric field

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Chemical Protein Synthesis by Native Chemical Ligation and Variations Thereof

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Chinese Journal of Chemistry 2019年第11期37卷 1181-1193页

作者： Siyao Wang Yogesh Abaso Thopate Qingqing Zhou Ping Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical EngineeringShanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China

For a long time,the total synthesis of proteins was considered as a "mission impossible" because of the tedious and complex synthetic steps and demanding purification processes.However,with the development of modern synthetic methodologies,many protein syntheses have now been reported.More importantly,through chemical synthesis,desired modifications can be installed to target proteins precisely,which is a major advantage over trad卜tional bio-synthesis approaches.This review summarizes the techniques developed for protein assembly,including native chemical ligation,5e-mediated ligation,and a range of other ligation methods. .

关键词： processes. methods. synthesis

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Influence of nozzle enabling strategy on spray deposition of crop protection unmanned aerial system

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 53-61页

作者： Wei Gu Xinyu Xue Chen Chen Qingqing Zhou Songchao Zhang Bin Peng Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China Key Laboratory of Aviation Plant Protection Ministry of Agriculture and Rural AffairsAnyang 455000HenanChina XAG Co. LtdGuangzhou 510663China

Proper nozzles arrangement is significant to improve spray deposition of crop protection unmanned aerial system(UAS).Besides fuselage structure,the control strategy is another nozzle location changing method when there are multiple sets of nozzles.A four-rotor crop protection UAS equipped with four centrifugal nozzles was used to conduct a field experiment in the rupturing stage of rice.Two sets of nozzles in the front and rear of the fuselage were enabled independently to investigate spray deposition,including spray coverage and droplet density on the sampling cards.Various nozzle rotating speeds and flight speeds were employed in the experiment to study the influence of nozzle location on the deposition.With different nozzle rotating speeds,the droplet spectrum could be controlled.The results show that the average coverage and average cumulative droplet density are negatively correlated with flight speed.Average droplet density is also negatively correlated with the droplet size.Spray deposition of front nozzles is significantly reduced compared with that of the rear nozzles under the same spray parameters,especially when the droplet size is too large or the flight speed is too fast.The reduction is mainly concentrated in the center area of the spray swath.As a result,the average cumulative droplet density of the front nozzles decreases by 25.96%in total.The average droplet density decreases by 18.54%when the droplet size is smaller than 100μm,decreases by 25.02%when between 100μm and 200μm,and decreases by more than half when larger than 200μm.This research can provide guidance for the installation of UAS nozzles and spray control strategy design.

关键词： crop protection unmanned aircraft system nozzles arrangement spray coverage droplet density

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Effect of slope position on leaf and fine root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations

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林业研究:英文版 2023年第6期34卷 1997-2009页

作者： qingqing Zhang Zaizhi zhou Weiwei Zhao Guihua Huang Gaofeng Liu Xiaofei Li Junduo Wu Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520People’s Republic of China Experimental Center of Tropical Forestry Chinese Academy of ForestryPingxiang 532600People’s Republic of China

Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils.Here we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation.The Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope position.The results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere soils.The lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in leaves.Nutrient accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils.Leaf C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope position.The contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively lower.Variations in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere soils.Chemical properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper slope.Correspondingly,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing factor.Overall,these results offer new insights for the sustainabili

关键词： Tectona grandis Stoichiometric ratio Rhizosphere soil Dominant trees Nutrient accumulation

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Protocatechuic acid and quercetin attenuate ETEC-caused IPEC-1 cell inflammation and injury associated with inhibition of necroptosis and pyroptosis signaling pathways

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1551-1568页

作者： Kan Xiao Mohan zhou qingqing Lv Pengwei He Xu Qin Dan Wang Jiangchao Zhao Yulan Liu Hubei Key Laboratory of Animal Nutrition and Feed Science Wuhan Polytechnic UniversityWuhan 430023People’s Republic of China Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleAR 72701USA

Background:Necroptosis and pyroptosis are newly identified forms of programmed cell death,which play a vital role in development of many gastrointestinal disorders.Although plant polyphenols have been reported to protect intestinal health,it is still unclear whether there is a beneficial role of plant polyphenols in modulating necroptosis and pyroptosis in intestinal porcine epithelial cell line(IPEC-1)infected with enterotoxigenic Escherichia coli(ETEC)K88.This research was conducted to explore whether plant polyphenols including protocatechuic acid(PCA)and quercetin(Que),attenuated inflammation and injury of IPEC-1 caused by ETEC K88 through regulating necroptosis and pyroptosis signaling pathways.Methods:IPEC-1 cells were treated with PCA(40μmol/L)or Que(10μmol/L)in the presence or absence of ETEC K88.Results:PCA and Que decreased ETEC K88 adhesion and endotoxin level(P<0.05)in cell supernatant.PCA and Que increased cell number(P<0.001)and decreased lactate dehydrogenases(LDH)activity(P<0.05)in cell supernatant after ETEC infection.PCA and Que improved transepithelial electrical resistance(TEER)(P<0.001)and reduced fluorescein isothiocyanate-labeled dextran(FD4)flux(P<0.001),and enhanced membrane protein abundance of occludin,claudin-1 and ZO-1(P<0.05),and rescued distribution of these tight junction proteins(P<0.05)after ETEC infection.PCA and Que also declined cell necrosis ratio(P<0.05).PCA and Que reduced mRNA abundance and concentration of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-8(P<0.001),and down-regulated gene expression of toll-like receptors 4(TLR4)and its downstream signals(P<0.001)after ETEC infection.PCA and Que down-regulated protein abundance of total receptor interacting protein kinase 1(t-RIP1),phosphorylated-RIP1(p-RIP1),p-RIP1/t-RIP1,t-RIP3,p-RIP3,mixed lineage kinase domain-like protein(MLKL),p-MLKL,dynamin-related protein 1(DRP1),phosphoglycerate mutase 5(PGAM5)and high mobility group box 1(HMGB1)(P<0.05)after ETEC infection.Moreover,PCA and Que reduced protein abundance of

关键词： Cell damage ETEC K88 Intestinal inflammation Necroptosis Protocatechuic acid Pyroptosis Quercetin

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KDM2B promotes IL-6 production and inflammatory responses through Brg1-mediated chromatin remodeling

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Cellular & Molecular Immunology 2020年第8期17卷 834-842页

作者： Qingqing Zhou Yunkai Zhang Bo Wang Wenhui zhou Yong Bi Wanwan Huai Xi Chen Yihan Chen Zhongmin Liu Xingguang Liu Zhenzhen Zhan Institute of Heart Failure Shanghai East HospitalTongji University School of Medicine200120ShanghaiChina National Key Laboratory of Medical Immunology&Institute of Immunology Second Military Medical University200433ShanghaiChina Shanghai Fourth People’s Hospital Tongji University School of Medicine200081ShanghaiChina Institute of Immunology Zhejiang University School of Medicine310058HangzhouChina Key Laboratory of Arrhythmias of the Ministry of Education of China Shanghai East HospitalTongji University School of Medicine200120ShanghaiChina

IL-6 plays important and pleiotropic roles in infection and inflammatory diseases,and its production needs to be tightly regulated.However,the epigenetic mechanism underlying Il6 gene transcription remains to be fully elucidated.Here,we report that lysine-specific demethylase 2b(KDM2B),which demethylates H3K4me3 and H3K36me2,is required in macrophages and dendritic cells for the induction of IL-6 but not TNF-α,IL-1,and IFN-β.Compared to wild-type mice,KDM2B-deficient mice were more resistant to endotoxin shock and colitis,with a less severe inflammatory pathogenesis phenotype and decreased IL-6 production in sera.KDM2B selectively bound the Il6 promoter but did not alter histone demethylation;instead,KDM2B interacted with Brahma-related gene 1(Brg1),the core ATPase subunit of SWI/SNF chromatin remodeling complexes,to facilitate chromatin accessibility of the Il6 promoter.Furthermore,KDM2B directly recruited RNA Polymerase II to further initiate and promote Il6 transcription.Thus,our finding identifies a novel nonclassical function of KDM2B in gene-specific transcription initiation and enhancement of Il6 independent of its demethylase activity and adds new insight into the specific epigenetic modification mechanism of inflammatory immune responses.

关键词： KDM2B IL-6 Brg1 Chromatin remodeling Inflammation

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The disbalance of LRP1 and SIRPα by psychological stress dampens the clearance of tumor cells by macrophages

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Acta Pharmaceutica Sinica B 2022年第1期12卷 197-209页

作者： Yanping Wu Xiang Luo Qingqing Zhou Haibiao Gong Huaying Gao Tongzheng Liu Jiaxu Chen Lei Liang Hiroshi Kurihara Yi-Fang Li Rong-Rong He Guangdong Engineering Research Center of Chinese Medicine&Disease Susceptibility Jinan UniversityGuangzhou 510632China International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Chinese Ministry of Education College of PharmacyJinan UniversityGuangzhou 510632China Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research College of PharmacyJinan UniversityGuangzhou 510632China Formula-pattern Research Center School of Traditional Chinese MedicineJinan UniversityGuangzhou 510632China Integrated Chinese and Western Medicine Postdoctoral Research Station Jinan UniversityGuangzhou 510632China Institute of Tumor Pharmacology College of PharmacyJinan UniversityGuangzhou 510632China

The relationship between chronic psychological stress and tumorigenesis has been well defined in epidemiological studies;however, the underlying mechanism remains underexplored. In this study, we discovered that impaired macrophage phagocytosis contributed to the psychological stressevoked tumor susceptibility, and the stress hormone glucocorticoid(GC) was identified as a principal detrimental factor. Mechanistically, GC disturbed the balance of the "eat me" signal receptor(low-density lipoprotein receptor-related protein-1, LRP1) and the "don’t eat me" signal receptor(signal regulatory protein alpha, SIRPa). Further analysis revealed that GC led to a direct, glucocorticoid receptor(GR)-dependent trans-repression of LRP1 expression, and the repressed LRP1, in turn, resulted in the elevatedgene level of SIRPa by down-regulating mi RNA-4695-3 p. These data collectively demonstrate that stress induces the imbalance of the LRP1/SIRPa axis and entails the disturbance of tumor cell clearance by macrophages. Our findings provide the mechanistic insight into psychological stress-evoked tumor susceptibility and indicate that the balance of LRP1/SIRPa axis may serve as a potential therapeutic strategy for tumor treatment.

关键词： Psychological stress Tumorigenesis Macrophages Phagocytosis LRP1 SIRPa Therapeutic target

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