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Journal of Analysis and Testing 2024年第03期8卷 262-269页

作者： Meixuan Li Lei Wang Ai Xu Ying Ding fengzhen yang Yanbin Li Jianhan Lin Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural University Center of Excellence for Poultry Science University of Arkansas

Inspired by ballpoint pen, an optical biosensor is developed for detection of Salmonellausing a mechanical step rotator with a dropper to greatly simplify operation, a high gradient magnetic field with immune magnetic nanobeads to specifically separate bacteria, and immune gold@platinum nanozymes with a smartphone to sensitively detect bacteria. First, the preloaded bacterial sample is drawn by the dropper to react with the immune magnetic nanobeads through repeated squeezing and releasing of the dropper, and the rotator is successively rotated and the dropper is repeatedly squeezed and released to achieve mixing of the bacteria, magnetic nanobeads and gold@platinum nanozymes, followed by magnetic separation to remove the background. Then, the conjugates are eff ectively washed with skim milk and ultrapure water, and the substrate are rapidly catalyzed into the product. Finally, the blue product is photographed and analyzed using a smartphone to obtain the Salmonella concentration. This biosensor could detect Salmonellaas low as 56 CFU/mL in～25 min.

关键词： gold@platinum nanozyme magnetic grid separation mechanical step rotator optical biosensor Salmonella detection

Pathogenicity of Cell Wall Degrading Enzymes Produced by Botryodiplodia theobromae Pat. against Mangoes

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Agricultural Biotechnology 2012年第6期1卷 18-21页

作者： Min LI Zhaoyin GAO Meijiao HU Shuo ZHOU Dongping yang Bo yang Jianxue YI fengzhen yang Environment and Plant Protection Research Institute CATAS Hainan Key Laboratory for Monitoring and Control of Tropical Agricultural Pests Hainan Engineering Research Center for Biological Control of Diseases and Pests on Tropical Crops College of Environment and Plant Protection Hainan University

[ Objective ] This study aimed to confirm the roles of cell wall degrading enzymes （CWDEs） produced by Botryodiplodia theobromae Pat. in the infec- tion of mango fruits. [ Method] Change of activities of five types of CWDEs produced by B. theobromae Pat. were studied under both in vitro culture and inocula- tion conditions, along with the pathogenicity and the ability of producing CWDEs of four post-harvest fangal pathogens（B, theobromae Pat. , Colletotrichum gloeos- porioides Penz. , Phomopsis mangiferae Ahmad and Dothiorella dominicana Pet. et Cif. ） which cause stem-end rot of mangoes. [ Result] B. theobromae Pat. was a- ble to produce polygalacturonase（PG）, pectinmethylgalacturonase（PMG）, polygalacturonic acid trans-eliminase （PGTE）, pectin methyltrans-eliminase （PMTE） and cellulase （ Cx. ） under both in vitro culture and inoculation conditions, of which activities of PG, Cx and PMG were significantly higher in than that in either PGTE or PMTE. Among three primary CWDEs, the peak of activities of PG and Cx appeared earlier and that of PMG occured later. The pathogenicity of B. theo- bromae Pat. was significantly higher than that of any other three pathogens; it is the same with the abilities of producing pectinase. [ Conclusion] This paper pro- vides theoretical bases for further exploring the mechanism of host-pathogen interaction and decreasing the post-harvest loss of mango fruits.

关键词： Botryodiplodia theobromae Pat cell wall degrading enzymes(CWDEs) Pathogenicity

Analysis and Verification of the Conserved MYB Binding Element in the DFR Promoter in Compositae

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 343-353页

作者： Jialei Guo fengzhen Li Guomin Shi Weimin Zhao Tao He State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining810016China School of Ecol-Environmental Engineering Qinghai UniversityXining810016China Key Laboratory of Landscape Plants of Qinghai Province Qinghai UniversityXining810016China

Anthocyanins,ubiquitous in the Compositae family,are regulated by MYB(v-myb avian myeloblastosis viral oncogene homolog),playing an important role in anthocyanin *** this study,we analyzed the regulation pathway in which the MYB protein of subgroup 6 promotes dihydroflavonol reductase(DFR)expression in Compositae,and validated this law in Saussurea medusa through yeast one-hybrid *** results showed that MYB and DFR underwent purification selection,DFR promoter analysis revealed the presence of MYB binding site(GAGTTGAATGG)and bHLH binding site(CANNTG)at the sense strand of 84–116 nucleotide residues from the start *** two motifs were separated by 9–10 nucleotide residues,as existed in the DFR promoters of many Compositae ***,the yeast one-hybrid experiment demonstrated that SmMYB1 can activate the promoter of *** results provide a reference for further functional study of DFR in Compositae.

关键词： Compositae anthocyanin DFR gene MYB gene

Principle of Hydrogen Isotope Geochemistry Paleo-altimeter and its Potential in Reconstructing Paleo-elevation of the Southeastern Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1051-1063页

作者： CUI fengzhen LIU-ZENG Jing LI Yunshuai XU Qiang TANG Maoyun WANG Heng SUN Zhaotong School of Earth System Science Tianjin UniversityTianjin 300072China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China School of Earth Science and Technology Southwest Petroleum UniversityChengdu 610500China Chongqing Earthquake Agency Chongqing 401147China

The reconstruction of paleo-elevation serves a dual purpose to enhance our comprehension of geodynamic processes affecting terrestrial landforms and to contribute significantly to the interpretation of atmospheric circulation and *** oxygen(δ~(18)O_w)and deuterium(δD_w)isotopes in atmospheric precipitation are systematically depleted with the increase of altitude,which are typical and widely applicated *** utilization of hydrogen isotope of hydrous silicate minerals within the shear zone system,volcanic glass,and plant leaf wax alkanes offers valuable insights for addressing evaporation and *** this paper,we review the principle,application conditions,and influencing factors of the hydrogen isotope *** addition,we discuss the feasibility of utilizing this technique for quantitatively estimating the paleo-elevation of the southeastern Tibetan Plateau,where multiple shear zones extend over hundred kilometers parallel to the topographic gradient.

关键词： paleo-elevation hydrogen isotope hydrous silicate minerals volcanic glass Tibetan Plateau

Macrophage exosomes modified by miR-365-2-5p promoted osteoblast osteogenic differentiation by targeting OLFML1

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Regenerative Biomaterials 2024年第3期3卷 134-147页

作者： Caiyao Hou Yujue Zhang Zhaoyong Lv Yurun Luan Jun Li Chunxiu Meng Kun Liu Xin Luo Liyu Chen fengzhen Liu Department of Materials Science and Engineering Liaocheng UniversityLiaocheng 252000China Liaocheng People's Hospital Liaocheng Hospital Affliated Shandong First Medical UniversityLiaocheng 252000China The Second Hospital Cheeloo College of MedicineShandong UniversityJinan 250023China

In the bone immune microenvironment,immune cells can regulate osteoblasts through a complex communication *** play a central role in mediating immune osteogenesis,exosomes derived from them have osteogenic regulation and can be used as cariers in bone tissue ***,there are problems with exosomal therapy alone,such as poor targeting,and the content of loaded molecules cannot reach the therapeutic *** this study,macrophage-derived exosomes modified with miR-365-2-5p were developed to accelerate bone ***3T3-E1 cells were incubated with the culture supermatants of Mo,M1 and M2 macrophages,and it was found that the culture medium of M2 macrophages had the most significant effects in contributing to ***-throughput sequencing identified that miR-365-2-5p was significantly expressed in exosomes derived from M2 *** incubated MC3T3-E1 with exosomes overexpressing or kmocking down miR-365-2-5p to examine the biological function of exosome miR-365-2-5p on MC3T3-E1 *** findings suggested that miR-365-2-5p secreted by exosomes increased the osteogenesis of ***,miR-365-2-5p had a direct influence over osteogenesis for *** analysis combined with dual luciferase detection indicated that miR-365-2-5p binded to the 3'-UTR of *** summary,exosomes secreted by M2 macrophages targeted OLFML1 through miR-365-2-5p to facilitate osteogenesis.

关键词： macrophage exosomes osteogenesis osteoimmunology

Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate

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Chinese Chemical Letters 2024年第3期35卷 282-286页

作者： Jin Huang Jinwen Li Rui Yan Yuanyuan Qu fengzhen Guo Lei Shen Can-liang Ma Jie Sun Zhenjiang Li Kai Guo State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Nanjing Advanced Biomaterials&Processing Equipment Lishui Economic Development ZoneNanjing 211299China

The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable ***,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of *** this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,*** intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the *** comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关键词： Zwitterionic ring-opening polymerization Cyclic polycarbonate Macrocycles Tetrahedral intermediate NHC carbene

Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-7页

作者： yang, yang Harbin Univ Coll Art & Design Harbin 150076 Peoples R China Northeast Forestry Univ Coll Mech & Elect Engn Harbin 150040 Peoples R China

As an important material for manufacturing resonant components of musical instruments, Paulownia has an important influence on the sound quality of Ruan. In this paper, a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning methods. Generally, the selection of materials for Ruan manufacturing relies primarily on manually weighing, observing, striking, and listening by the instrument technician. Deficiencies in scientific theory have hindered the quality of the finished Ruan. In this study, nine Ruans were manufactured, and a prediction model of Ruan sound quality was proposed based on the raw material information of Ruans. Out of a total of 180 data sets, 145 and 45 sets were chosen for training and validation, respectively. In this paper, typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in Ruan. The vibration characteristics of the wood were tested, and a model for predicting the evaluation of Ruan's acoustic qualities was developed by measuring the vibration characteristics of the resonating plate material. The acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural network. The results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard wood. When the model-predicted values were compared with the traditional predicted results, it was found that the generalized regression neural network had good performance, achieving an accuracy of 93.8% which was highly consistent with the experimental results. It was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods YOUNGS MODULUS INTERNAL-FRICTION PREDICTION

小学英语教学中培养学生学科核心素养的可行性策略

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英语教师 2023年第16期23卷 117-119,132页

作者：杨凤珍广州市增城区增江街第二小学广东广州511300

简述英语学科核心素养的内涵及在小学英语教学中培养学生学科核心素养的重要性。在此基础上,结合教学实例,提出培养学生英语学科核心素养的可行性策略,即强化学生多元化的语言输出练习,提高学生的语言能力;挖掘拓展教材中的文化知识,培... 详细信息

简述英语学科核心素养的内涵及在小学英语教学中培养学生学科核心素养的重要性。在此基础上,结合教学实例,提出培养学生英语学科核心素养的可行性策略,即强化学生多元化的语言输出练习,提高学生的语言能力;挖掘拓展教材中的文化知识,培养学生的文化意识;善用启发性的教学模式,提升学生的思维品质;采用灵活、有趣的教学方法,强化学生的学习能力。

关键词：小学英语英语学科核心素养语言能力文化意识思维品质学习能力

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情感与高校女生体育教学

体育科研 1998年第2期19卷 50-52页

作者：杨凤珍苏州城建环保学院江苏215011

扼要分析情感在提高高校女生体育教学质量中的作用及培养女大学生对体育课情感的途径。

关键词：情感高校女生体育教学

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang Guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making