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Exploring ratiometric endolysosomal pH nanosensors with hydrophobic indicators responding at the nanoscale interface and multiple fluorescence resonance energy transfers

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Nano Research 2022年第4期15卷 3471-3478页

作者： Qinghan Chen Jingying Zhai Jing Li yifu wang Xiaojiang Xie School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China

Compared with conventional water-soluble fluorescence probes,pH-sensitive fluorescent nanosensors based on hydrophobic indicators remain largely unexplored.We report here the unique pH response of the nanosensors with a hydrophobic indicator(Ch3,a Nile Blue derivative)in polymeric nanoparticles(NPs).At the aqueous-organic interface of the NPs,spectral overlap and dye accumulation caused significant Förster resonance energy transfer(FRET)not only between the protonated and deprotonated Ch3(hetero-FRET),but also between the protonated and deprotonated Ch3 themselves(homo-FRET).The pH response was simulated according to an interfacial response mechanism and the dynamic range was found to depend on the size of the NPs and dye distribution(Kp).Therefore,adjusting the size of the NPs and the local dye concentration gave rise to a series of dynamic sensing ranges with apparent pKa values from 2.7 to 9.6 based on a single indicator.The nanosensors were successfully delivered to HeLa cells to monitor subcellular pH values in the endosomes and lysosomes.Based on cellular calibrations,the average pH in the organelles were determined to be ca.4.7.Moreover,the pH neutralization process during lysosome membrane permeabilization(LMP)induced by hydrogen peroxide stimulation was also successfully visualized with the nanosensors.

关键词： pH nanosensor fluorescence resonance energy transfer(FRET) lysosome interfacial response cell pH chromoionophore

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Pine wilt disease detection in high-resolution UAV images using object-oriented classification

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Journal of Forestry Research 2022年第4期33卷 1377-1389页

作者： Zhao Sun yifu wang Lei Pan Yunhong Xie Bo Zhang Ruiting Liang Yujun Sun National Forestry and Grassland Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People’s Republic of China

Pine wilt disease(PWD)is currently one of the main causes of large-scale forest destruction.To control the spread of PWD,it is essential to detect affected pine trees quickly.This study investigated the feasibility of using the object-oriented multi-scale segmentation algorithm to identify trees discolored by PWD.We used an unmanned aerial vehicle(UAV)platform equipped with an RGB digital camera to obtain high spatial resolution images,and multiscale segmentation was applied to delineate the tree crown,coupling the use of object-oriented classification to classify trees discolored by PWD.Then,the optimal segmentation scale was implemented using the estimation of scale parameter(ESP2)plug-in.The feature space of the segmentation results was optimized,and appropriate features were selected for classification.The results showed that the optimal scale,shape,and compactness values of the tree crown segmentation algorithm were 56,0.5,and 0.8,respectively.The producer’s accuracy(PA),user’s accuracy(UA),and F1 score were 0.722,0.605,and 0.658,respectively.There were no significant classification errors in the final classification results,and the low accuracy was attributed to the low number of objects count caused by incorrect segmentation.The multi-scale segmentation and object-oriented classification method could accurately identify trees discolored by PWD with a straightforward and rapid processing.This study provides a technical method for monitoring the occurrence of PWD and identifying the discolored trees of disease using UAV-based high-resolution images.

关键词： Object-oriented classification Multi-scale segmentation UAV images Pine wilt disease

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Developing nonlinear additive tree crown width models based on decomposed competition index and tree variables

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林业研究:英文版 2023年第5期34卷 1407-1422页

作者： Siyu Qiu Peiwen Gao Lei Pan Lai Zhou Ruiting Liang Yujun Sun yifu wang National Forestry and Grassland Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People’s Republic of China The School of Information Science and Technology Beijing Forestry UniversityBeijing 100083People’s Republic of China Department of Forestry Shanxi Agricultural UniversityShanxi 030801People’s Republic of China

Crown development is closely related to the biomass and growth rate of the tree and its width(CW)is an important covariable in growth and yield models and in forest management.To date,various CW models have been proposed.However,limited studies have explicitly focused on additive and inherent correlation of crown components and total CW as well as the influence of competition on crown radius from the corresponding direction.In this study,two model systems were used,i.e.,aggregation method system(AMS)and disaggregation method system(DMS),to develop crown width additive model systems.For calculating spatially explicit competition index(CI),four neighbor tree selection methods were evaluated.CI was decomposed into four cardinal directions and added into the model systems.Results show that the power model form was more proper for our data to fit CW growth.For each crown radius and total CW,height to the diameter at breast height(HDR)and basal area of trees larger than the subject tree(BAL)significantly contributed to the increase of prediction accuracy.The 3-m fixed radius was optimal among the four neighborhoods selection ways.After adding decomposed competition Hegyi index into model systems AMS and DMS,the prediction accuracy improved.Of the model systems evaluated,AMS based on decomposed CI provided the best performance as well as the inherent correlation and additivity properties.Our study highlighted the importance of decomposed CI in tree CW modelling for additive model systems.This study focused on methodology and could be applied to other species or stands.

关键词： Competition decomposition Additivity Crown width Spatially explicit Competitor selection

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Only Sunda and Chinese pangolin(Pholidota)are naturally distributed in China

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Integrative Zoology 2023年第4期18卷 704-709页

作者： Peng CEN Jiankun SUN Qiaoyan wang Fuhua ZHANG Lianxian MO Amna MAHMOOD Jiaqi LI yifu wang Shibao WU School of Life Science South China Normal UniversityGuangzhouChina Administration of Xishuangbanna National Nature Reserve XishuangbannaChina Administration of Gaoligongshan National Nature Reserve in Baoshan BaoshanChina Nanjing Institute of Environmental Science Ministry of Environmental ProtectionNanjingChina The University of Hong Kong HongkongChina IUCN SSC Pangolin Specialist Group LondonUK

INTRODUCTION Pangolin is the common name for animals in the Family Pholidota,Mammalia,which consists of eight extant species.All pangolin species have been listed as critically endangered(CR),endangered(EN),or vulnerable(VU)species in the International Union for Conservation of Nature(IUCN)Red List of Threatened Species(Challender et al.2020).In June 2020,the Chinese government upgraded the Chinese pangolin(Manis pentadactyla Linnaeus,1758)from a national second-class protected animal to a national first-class protected animal.In February 2021,the Sunda pangolin(Manis javanica Desmarest,1822)and the Indian pangolin(Manis crassicaudata Geoffroy,1803)were added to the list of national first-class protected animals.However,the number of species of pangolins naturally distributed in China varies in the literature:Some sources have recorded only one species,namely the Chinese pangolin(Nowak&Paradiso 1983;Sheng 1999),while most have recorded two species,namely the Chinese pangolin and Indian pangolin(Allen 1938;Zhang 1997;wang 2003;Wu et al.2005a;Hu&Hu 2017).

关键词： protected Indian listed

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Anti-melanoma effect and action mechanism of a novel chitosan-based composite hydrogel containing hydroxyapatite nanoparticles

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Regenerative Biomaterials 2022年第1期9卷 665-676页

作者： Kejia Xu yifu wang Yao Xie Xiaoyan Zhang Wei Chen Zhongtao Li Tingting wang Xiao Yang Bo Guo Lin wang Xiangdong Zhu Xingdong Zhang Department of Dermatovenereology West China HospitalSichuan UniversityChengdu 610041China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610041China Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041China

Hydroxyapatite nanoparticles(HANPs)have been increasingly regarded and reported due to their potential anti-tumor ability.Previously,we found that the rod-like HANPs had good application potential for cutaneous melanoma(CMM).To satisfy the actual requirements in repairing post-operative skin defects and inhibiting CMM recurrence after tumorectomy,we constructed a novel chitosan/alginate(CS/Alg)hydrogel containing the aforementioned HANPs.The in vitro cell experiments confirmed that activated mitochondrial-dependent apoptosis was tightly related to the anti-tumor ability of HANPs.Specifically,we further discovered several target proteins might be involved in abnormal activating Wnt,proteoglycans in cancer,oxidative phosphorylation and p53 signaling pathways.The in vivo animal experiments demonstrated that the HANPsloaded CS/Alg hydrogel(CS/Alg/HANPs)had a similar effect on inhibiting tumor growth as HANPs,and CS/Alg hydrogel as well as phosphate buffered saline(PBS)group(control)not showed any effect,proving the key role of HANPs.The immunohistochemical staining demonstrated a tumor inhibition via the mitochondria-mediated apoptosis pathway,consistent with the in vitro evaluation.Moreover,CS/Alg/HANPs exhibited no additional biosafety risk to the functions of major organs.Overall,this CS/Alg/HANPs hydrogel has substantial application potential for treating CMM.

关键词： melanoma hydroxyapatite nanoparticles composite hydrogel tumor inhibition biosafety

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热处理对Fe−6.5%Si磁粉芯性能的影响

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粉末冶金技术 2024年第2期42卷 177-183页

作者：邱玥贺弋海王义富林少川孔辉王锐安徽工业大学冶金工程学院马鞍山243002 马鞍山市申马机械制造股份有限公司马鞍山243021

对Fe-6.5%Si粉末(质量分数)进行不同温度的热处理实验,经压制后得到Fe-6.5%Si磁粉芯,并对磁粉芯进行不同温度的热处理,探究热处理工艺对Fe-6.5%Si磁粉芯磁导率和损耗等磁性能的影响。结果发现:粉末热处理可以大幅度消除气雾化制粉过程... 详细信息

对Fe-6.5%Si粉末(质量分数)进行不同温度的热处理实验,经压制后得到Fe-6.5%Si磁粉芯,并对磁粉芯进行不同温度的热处理,探究热处理工艺对Fe-6.5%Si磁粉芯磁导率和损耗等磁性能的影响。结果发现:粉末热处理可以大幅度消除气雾化制粉过程中合金粉末受高压气体冲击造成的缺陷,并减少粉末中的C、O含量;随着热处理温度的升高,粉末的矫顽力先增后减,饱和磁化强度逐渐降低。通过对压制成型磁粉芯进行热处理也能够改善磁粉芯的磁性能,不同温度热处理后损耗均维持在600~700 mW∙cm^(-3)之间,最低值为625 mW∙cm^(-3)。综合分析,用经900℃热处理粉末制成的磁粉芯在800℃进行后续热处理,磁粉芯磁导率、损耗等性能综合较优。

关键词：磁粉芯铁硅合金热处理磁性能

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The signaling pathway in modulating bone metabolism after dental implant in diabetes

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BIOCELL 2021年第6期45卷 1509-1519页

作者： XIAOMEI HAN SHUYING ZHANG yifu wang CHANGE QI PENGNYU GUO YALI XU GUANGHUI LYU Department of Oral Implantology Affiliated Hospital of Chifeng UniversityChifeng024000China

Diabetes Mellitus is a systematic disease with complications in multi-organs,including decreased implant osseointegration and a high failure rate of dental transplants.Accumulating evidence indicates that the signaling pathway directly impacts the process of bone metabolism and inflammatory response implicated with dental implants in diabetic patients.This review summarizes the recent advance in signaling pathways regulate osseointegration and inflammatory response in dental transplantation,aiming to identify the potential therapeutic target to reduce the dental transplant failure in diabetes patients,with emphasis on the surface characteristics of the implant,inflammatory signaling,AMPK,PPARγ,WNT,ROS,and adiponectin signaling.

关键词： Diabetes Osseointegration Titanium Wnt ROS Adiponectin PPARγ Dental transplant

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机器学习算法在降水和气温多模式集成中的应用

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水资源保护 2024年第3期40卷 106-115页

作者：鞠琴吴金雨王兴平刘小妮王逸夫段远强吴可馨蒋晓蕾河海大学水灾害防御全国重点实验室江苏南京210098 中国气象局水文气象重点开放实验室江苏南京210024 四川省紫坪铺开发有限责任公司四川成都610091 扬州大学水利科学与工程学院江苏扬州225000

选取CMIP6中5种全球气候模式,利用算术平均、权重平均、多元线性回归、BP神经网络、长短期记忆(LSTM)神经网络和随机森林(RF)等6种多模式集成方法,基于黄河流域水源涵养区历史降水量和气温数据,评估不同集成方法的模拟效果,并选取模拟... 详细信息

选取CMIP6中5种全球气候模式,利用算术平均、权重平均、多元线性回归、BP神经网络、长短期记忆(LSTM)神经网络和随机森林(RF)等6种多模式集成方法,基于黄河流域水源涵养区历史降水量和气温数据,评估不同集成方法的模拟效果,并选取模拟效果最好的多模式集成方法预估未来SSP1-2.6、SSP2-4.5和SSP5-8.53种情景下黄河流域水源涵养区的降水和气温变化趋势。结果表明:多模式集成能很好地再现基准期降水和气温变化,3种机器学习算法表现相对较好,其中LSTM神经网络最好;在未来3种情景下,多年平均降水量均有所增加,四季降水量变化各有差异;SSP1-2.6情景下年降水量峰值出现在各时段初期,SSP2-4.5和SSP5-8.5情景下的年降水量呈增长趋势,远期下降趋势较明显;3种情景下气温都呈上升趋势,但变化差异较大,增温幅度和速率由小到大为SSP1-2.6、SSP2-4.5、SSP5-8.5,秋季气温增幅最大,冬季最小;多模式集成方法对未来降水量和气温的预估存在较大的不确定性,均表现为中远期大于近期,降水量预估的不确定性比气温大,其中降水量秋冬季不确定性明显大于春夏季。

关键词： CMIP6 全球气候模式多模式集成 LSTM神经网络黄河流域

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基于无人机多维数据集的森林地上生物量估测模型研究

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农业机械学报 2024年第6期55卷 186-195,236页

作者：孙钊谢运鸿王宝莹谭军王轶夫孙玉军中国地质调查局军民融合地质调查中心成都610036 北京林业大学森林资源和环境管理国家林业和草原局重点开放性实验室北京100083

森林地上生物量(Aboveground biomass,AGB)是评价森林生长情况的重要指标。基于数字航空摄影(Digital aerial photography,DAP)生成的二维和三维数据,分别计算了41个点云高度变量和16个可见光植被指数,利用6种回归算法(随机森林(RF... 详细信息

森林地上生物量(Aboveground biomass,AGB)是评价森林生长情况的重要指标。基于数字航空摄影(Digital aerial photography,DAP)生成的二维和三维数据,分别计算了41个点云高度变量和16个可见光植被指数,利用6种回归算法(随机森林(RF)、袋装树(BT)、支持向量回归(SVR)、Cubist、类别型特征提升(CatBoost)、极端梯度提升(XGBoost))分别构建了单一变量集和综合变量集AGB估测模型,探索了不同变量对于AGB估测模型的贡献。研究结果表明光谱数据集和点云数据集AGB预测模型精度最高分别为Cubist和XGBoost,R^(2)分别为0.5309和0.6395。组合数据集最高精度模型为XGBoost,R^(2)达到0.7601,XGBoost模型具有更高的AGB估测稳定性。研究还表明6种机器学习模型的贡献主要取决于所考虑的回归方法,所选择的特征个数和特征对模型的重要性在不同的模型中并不一致。DOM光谱特征在AGB的估测中具有更高的重要性。总体来说,二维和三维数据的结合能够有效提高森林AGB估测精度,基于无人机倾斜摄影获取的RGB影像能够实现森林AGB的快速无损估计。

关键词：森林地上生物量估测模型无人机密集点云 SfM 可见光植被指数机器学习

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从“两会”议案提案解读数字中国建设

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竞争情报 2024年第2期20卷 35-42页

作者：李颖王一夫南开大学商学院信息资源管理系天津300071

“数字中国”是由党中央发起,全国人民共同参与,旨在加速建设社会主义现代化强国、实现中华民族伟大复兴的数字化运动。全国“两会”作为汇集民智、反映民意、影响民生的重要政治舞台,影响国家未来重点发展方向。本文基于2023年全国“... 详细信息

“数字中国”是由党中央发起,全国人民共同参与,旨在加速建设社会主义现代化强国、实现中华民族伟大复兴的数字化运动。全国“两会”作为汇集民智、反映民意、影响民生的重要政治舞台,影响国家未来重点发展方向。本文基于2023年全国“两会”代表委员关于数字中国建设的议案提案,运用NVivo 11软件进行文本分析,从整体建设及重点问题与挑战两方面梳理了数字中国建设的发展现状,并在此基础上对未来数字中国建设提出相应建议与展望。

关键词： “两会” 议案提案数字中国

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