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Cenozoic plants from Tibet:An extraordinary decade of discovery,understanding and implications

Science China Earth sciences 2023年第2期66卷 205-226页

作者： Zhekun ZHOU Jia LIU Linlin CHEN Robert A.SPICER Shufeng LI Jian HUANG Shitao ZHANG Yongjiang HUANG Linbo JIA Jinjin HU Tao SU CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla666303China CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650204China School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton KeynesMK76AAUK faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China State Key Laboratory of Paleobiology and Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing210008China

Plant fossils play an important role in understanding landscape evolution across the Tibetan Region,as well as plant diversity across wider eastern *** the last decade or so,paleobotanical investigations within the Tibet Region have led to a paradigm shift in our understanding of how the present plateau formed and how this affected the regional climate and *** is because:(1)Numerous new taxa have been *** all the Cenozoic records of new plant fossil species reported from the Tibet(Xizang)Autonomous Region 45 out of 63(70%)were documented after *** these,many represent the earliest records from Asia,or in some cases worldwide,at the genus or family level.(2)These fossils show that during the Paleogene,the region now occupied by the Tibetan Plateau was a globally significant floristic exchange *** on paleobiogeographic studies,grounded by fossil evidence,there are four models of regional floristic migration and exchange,i.e.,into Tibet,out of Tibet,out of India and into/out of Africa.(3)Plant fossils evidence the asynchronous formation histories for different parts of the Tibetan *** most of the Paleogene,there was a wide east-west trending valley with a subtropical climate in central Tibet bounded by high(>4 km)mountain systems,but that by the early Oligocene the modern high plateau had begun to form by the rise of the valley *** reconstructions using radiometrically-dated plant fossil assemblages in southeastern Tibet show that by the earliest Oligocene southeastern Tibet(including the Hengduan Mountains)had reached its present elevation.(4)The coevolution between vegetation,landform and paleoenvironment is evidenced by fossil records from what is now the central Tibetan *** the Paleocene to Pliocene,plant diversity transformed from that of tropical,to subtropical forests,through warm to cool temperate woodland and eventually to deciduous shrubland in response to landscape evolution from a seas

关键词： Tibetan Plateau Cenozoic Paleobotany Flora Central valley Biodiversity

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Gauss Gradient and SURF Features for Landmine Detection from GPR Images

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Computers, Materials & Continua 2022年第6期71卷 4457-4486页

作者： Fatma M.El-Ghamry Walid El-Shafai Mahmouad I.Abdalla Ghada M.El-Banby Abeer D.Algarni Moawad I.Dessouky Adel S.Elfishawy Fathi E.Abd El-Samie Naglaa F.Soliman Department of Electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazigSharqia44519Egypt Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenoufia32952Egypt Department of Industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Recently,ground-penetrating radar(GPR)has been extended as a well-known area to investigate the subsurface ***,its output has a low resolution,and it needs more processing for more *** paper presents two algorithms for landmine detection from GPR *** first algorithm depends on a multi-scale technique.A Gaussian kernel with a particular scale is convolved with the image,and after that,two gradients are estimated;horizontal and vertical ***,histogram and cumulative histogram are estimated for the overall gradient *** bin values on the cumulative histogram are used for discrimination between images with and without ***,a neural classifier is used to classify images with cumulative histograms as feature *** second algorithm is based on scale-space analysis with the number of speeded-up robust feature(SURF)points as the key parameter for *** addition,this paper presents a framework for size reduction of GPR images based on decimation for efficient *** further classification steps can be performed on images after *** sensitivity of classification accuracy to the interpolation process is studied in detail.

关键词： GPR images cumulative histogram gradient image neural classifier SURF

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Synthesis and in vitro Antimycobacterial Activity of Moxifloxacin Methylene and Ethylene Isatin Derivatives

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Chemical Research in Chinese Universities 2012年第1期28卷 61-66页

作者： FENG Lian-shun, LIU Ming-liang, WANG Shuo, CHAI Yun, LI Su-jie and GUO Hui-yuan Institute of Medicinal biotechnology, Chinese Academy of Medical sciences and Peking Union Medical College, Beijing 100050, P. R. China Institute of Medicinal biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050

A series of novel moxifloxacin methylene and ethylene isatin derivatives with remarkable improvement in lipophilicity, compared to the parent moxifloxacin, was designed, synthesized and characterized by 1H NMR, MS and HRMS. These derivatives were initially evaluated for their in vitro antimycobacterial activity against M. smegmatis CMCC 93202. Compounds 3a―3f, 5a, 5f and 5j were chosen for the further evaluation of their in vitro activity against Mycobacterium tuberculosis（MTB） H37Rv ATCC 27294 and MDR-MTB 09710. All the target com pounds[minimum inhibitory concentration（MIC）： 0.39―〉16 μg/mL] were far more active than rifampin（MIC： 2.0―〉256 μg/mL）, but less active than moxifloxacin（MIC： 0.1―1.0 μg/mL） against the three tested strains. The most active compounds 3a and 3c were found to be 2―64 fold more potent than isoniazid and rifampin against M. smegmatis CMCC 93202, 2 fold more potent than rifampin against MTB H37Rv ATCC 27294, and 16―〉64 fold more potent than ethambutol, isoniazid and rifampin against MDR-MTB 09710.

关键词： Moxifloxacin derivative Antimycobacterial activity Isatin

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Effects of Nitrogen Application on Chlorophyll Fluorescence Parameters and Leaf Gas Exchange in Naked Oat

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Journal of Integrative Agriculture 2013年第12期12卷 2164-2171页

作者： LIN Ye-chun HU Yue-gao REN Chang-zhong GUO Lai-chun WANG Chun-long JIANG Ying WANG Xue-jiao Phendukani Hlatshwayo ZENG Zhao-hai College of Agronomy and biotechnology China Agricultural University Baicheng Academy of Agricultural sciences KZN Department of Agriculture

Naked oat（Avena nuda L.） was originated from China,where soil nitrogen（N） is low *** responses of chlorophyll（Chl.） fluorescence parameters and leaf gas exchange to N application were analysed in this *** the N application rate ranged from 60 to 120 kg ha-1,variable fluorescence（F v）,the maximal fluorescence（F m）,the maximal photochemical efficiency（F v /F m）,quantum yield（Φ PS II） of the photosynthetic system II（PS II）,electron transport rate（ETR）,and photochemical quenching coefficient（qP） increased with N application level,however,non-photochemical quenching coefficient（qN） ***,there was no difference in initial fluorescence（F o） with further more N *** maximum net photosynthetic rate（P max）,apparent dark respiration rate（R d） and light saturation point（LSP） were improved with 40-56 kg N ha-1as basal fertilizer and 24-40 kg N ha-1as top dressing fertilizer applied at jointing *** quantum yield（α） was decreased with 24 kg N ha-1as basal fertilizer and 56 kg N ha-1as top dressing ***-leaf net photosynthetic rate（P n） was significantly enhanced at the jointing and heading stages with 40-56 kg N ha-1as basal fertilizer; in addition,increased at grain filling stage of naked oat with 40-56 kg N ha-1as top dressing fertilizer.90 kg N ha-1（50-70% as basal fertilizer and 30-50% as top dressing fertilizer） application is recommended to alleviate photodamage of photosystem and improve the photosynthetic rate in naked oat.

关键词： Avena nuda nitrogen fertilizer nitrogen application chlorophyll fluorescence gas exchange

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Development of Alfalfa (Medicago sativa L.) Regeneration System and Agrobacterium-Mediated Genetic Transformation

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Agricultural sciences in China 2010年第2期9卷 170-178页

作者： ZHANG He HUANG Qi-man SU Jin biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

The regeneration ability of four alfalfa （Medicago sativa L.） cultivars, Xinjiang Daye, Longdong, Gannong 1 and Gannong 3, was studied, and the effects of various cultivars, explant sources and medium recipes on regeneration were compared. The better callus forming frequency obtained from hypocotyls of Xinjiang Daye is 88.5% and regeneration frequency is 9.8% in our initial experiments. To further optimize regeneration system for genetic transformation, we therefore changed concentrations of plant growth regulators and supplemented with glutamine into callus-induction and shoot-regeneration media. Callus forming frequency and shoot differentiation frequency were increased to 100%. The time taken to generate transgenic plants （16 weeks） was shorter than that for previouse procedure （25 weeks） and regeneration frequency was promoted to 15.1%. The results show that addition of glutamine is particularly important for shortening period of regeneration and promoting regeneration frequency. For study of genetic transformation of alfalfa, Agrobacterium tumefaciens-mediated transformation of Xinjiang Daye was developed based on this optimized regeneration system. The plant expression vector carrying two glutamine synthetases （GS 1 and GS2） and △1-pyrroline-5-carboxylate synthetase （P5CS） gene was used for alfalfa in vitro transformation. Six transgenic alfalfa plantlets with resistance to PPT were obtained. The introduction of foreign genes into plants was assessed in the transformants by PCR analysis and Southern hybridizations.

关键词： alfalf glutamine synthetases △1-pyrroline-5-carboxylate synthetase Agrobacterium tumefaciens-mediated transformation transgenic alfalfa

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Stoichiometric Conversion of Maltose for Biomanufacturing by In Vitro Synthetic Enzymatic Biosystems

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BioDesign Research 2022年第1期2022卷 217-227页

作者： Guowei Li Xinlei Wei Ranran Wu Wei Zhou Yunjie Li Zhiguang Zhu Chun You Tianjin Institute of Industrial biotechnology Chinese Academy of Sciences32 West 7th AvenueTianjin Airport Economic AreaTianjin 300308China College of biotechnology Tianjin University of Science and Technology1038 Dagu NanluHexi DistrictTianjin 300457China National Technology Innovation Center of Synthetic Biology Tianjin 300308China

Maltose is a natural α-(1,4)-linked disaccharide with wide applications in food industries and microbial fermentation. However,maltose has scarcely been used for in vitro biosynthesis, possibly because its phosphorylation by maltose phosphorylase (MP)yields β-glucose 1-phosphate (β-G1P) that cannot be utilized by α-phosphoglucomutase (α-PGM) commonly found in in vitrosynthetic enzymatic biosystems previously constructed by our group. Herein, we designed an in vitro synthetic enzymaticreaction module comprised of MP, β-phosphoglucomutase (β-PGM), and polyphosphate glucokinase (PPGK) for thestoichiometric conversion of each maltose molecule to two glucose 6-phosphate (G6P) molecules. Based on this syntheticmodule, we further constructed two in vitro synthetic biosystems to produce bioelectricity and fructose 1,6-diphosphate (FDP),respectively. The 14-enzyme biobattery achieved a Faraday efficiency of 96.4% and a maximal power density of 0.6mW/cm^(2),whereas the 5-enzyme in vitro FDP-producing biosystem yielded 187.0mM FDP from 50 g/L (139mM) maltose by adopting afed-batch substrate feeding strategy. Our study not only suggests new application scenarios for maltose but also provides novelstrategies for the high-efficient production of bioelectricity and value-added biochemicals.

关键词： enzymatic utilized maximal

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Review of the anticancer activities of bee products

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Asian Pacific Journal of Tropical Biomedicine 2014年第5期4卷 337-344页

作者： Pongsathon Premratanachai Chanpen Chanchao Program of biotechnology faculty of Science Chulalongkorn University Department of Biology faculty of Science Chulalongkorn University

Bee products have long been used in traditional *** raw materials,crude extracts and purified active compounds from them have been found to exhibil interesting bioactivities,such as antimicrobial,anti-inflammatory and antioxidant *** addition,they have been widely used in the treatment of many immune-related diseases,as well as in recent times in the treatment of *** product peptides induce apoptotic cell death in vitro in several transformed(cancer) human cell lines,including those derived from renal,lung,liver,prostate,bladder and lymphoid *** bioactive natural products ***,prove to be useful as part of a novel targeted therapy for some types of cancer,such as prostate and breast *** review summarizes the current knowledge regarding the in vivo and in vitro potential of selective bee products against tumor cells.

关键词： Bee products Cancer cells Chrysin Flavonoid Inflammatory Propolis

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In vitro larvicidal potential against Anopheles stephensi and antioxidative enzyme activities of Ginkgo biloba,Stevia rebaudiana and Parthenium hysterophorous

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Asian Pacific Journal of Tropical Medicine 2011年第3期4卷 169-175页

作者： Nisar Ahmad Hina Fazal Bilal H Abbasi Mazhar Iqbal Department of biotechnology Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabad 45320Pakistan Nuclear Institute for Food and Agriculture(NIFA) Peshawar 2500Pakistan Department of Plant sciences Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabad 45320Pakistan Pakistan Council of Scientific and Industrial Research(PCSIR)Laboratories Complex Peshawar 2500Pakistan

Objective:To investigate in vitro larvicidal and antioxidant enzymes potential of the medicinal plants Ginkgo biloba（***）,Stevia rebaudiana（***） and Parthenium hysterophorous（***） against Anopheles stephensi（***） 4th instars larvae. Methods:For evaluation of larvicidal potential,the ethanolic,methanolic and dichloromethane leaves extracts of three different plants were used in dose-dependent experiments in two media, while the antioxidant enzymes activities were investigated using four different methods viz., superoxide dismutase,peroxidase,ascorbate and ***:*** has developed resistance to various synthetic insecticides,making its control increasingly *** comparative performance of ethanolic extracts（65%-90%） was found better than the methanolic extract（70%-87%） and dichloromethane extract（60%-70%）.Among the three plants extracts tested in two media,*** exhibited higher larvicidal activity with LC50（24 h） in methanolic extract than *** and *** and *** exhibited the strongest antioxidative enzymes activity and *** were less active and no significant difference was ***:These three plants exhibit larvicidal potential and can be further used for vector control alternative to synthetic insecticide due to eco-friendly and diseases control,furthermore these plant species have potent antioxidative enzyme activities, therefore,making them strong natural candidate particularly for diseases which are caused due to free radicals.

关键词： Larvicidal activity Antioxidative enzymes activities Anopheles stephensi

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An Efficient CNN-Based Hybrid Classification and Segmentation Approach for COVID-19 Detection

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Computers, Materials & Continua 2022年第3期70卷 4393-4410页

作者： Abeer D.Algarni Walid El-Shafai Ghada M.El Banby Fathi E.Abd El-Samie Naglaa F.Soliman Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh 84428Saudi Arabia Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazigSharqia 44519Egypt

COVID-19 remains to proliferate precipitously in the *** has significantly influenced public health,the world economy,and the persons’***,there is a need to speed up the diagnosis and precautions to deal with COVID-19 *** this explosion of this pandemic,there is a need for automated diagnosis tools to help specialists based onmedical *** paper presents a hybrid Convolutional Neural Network(CNN)-based classification and segmentation approach for COVID-19 detection from Computed Tomography(CT)*** proposed approach is employed to classify and segment the COVID-19,pneumonia,and normal CT *** classification stage is firstly applied to detect and classify the input medical CT ***,the segmentation stage is performed to distinguish between pneumonia and COVID-19 CT *** classification stage is implemented based on a simple and efficient CNN deep learning *** model comprises four Rectified Linear Units(ReLUs),four batch normalization layers,and four convolutional(Conv)*** layer depends on filters with sizes of 64,32,16,and 8.A2×2windowand a stride of 2 are employed in the utilized four max-pooling layers.A soft-max activation function and a Fully-Connected(FC)layer are utilized in the classification stage to perform the detection *** the segmentation process,the Simplified Pulse Coupled Neural Network(SPCNN)is utilized in the proposed hybrid *** proposed segmentation approach is based on salient object detection to localize the COVID-19 or pneumonia region,*** summarize the contributions of the paper,we can say that the classification process with a CNN model can be the first stage a highly-effective automated diagnosis *** the images are accepted by the system,it is possible to perform further processing through a segmentation process to isolate the regions of interest in the *** region of interest can be assesses both automatically and through ***

关键词： COVID-19 segmentation classification CNN SPCNN CT images

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PIF4 and HOOKLESS1 Impinge on Common Transcriptome and Isoform Regulation in Thermomorphogenesis

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Plant Communications 2020年第2期1卷 45-53页

作者： Huanhuan Jin Jingya Lin Ziqiang Zhu Jiangsu Key Laboratory for Biodiversity and biotechnology College of Life SciencesNanjing Normal UniversityNanjing 210023China Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations Lanzhou UniversityLanzhou 730000China

High temperature activates the transcription factor PHYTOCHROME-INTERACTING FACTOR4(PIF4)to stimulate auxin signaling,which causes hypocotyl elongation and leaf hyponasty(thermomorphogenesis).HOOKLESS1(HLS1)is a recently reported positive regulator of thermomorphogenesis,but the molecular mechanisms by which HLS1 regulates thermomorphogenesis remain *** this study,we initially compared PIF4-and/or HLS1-dependent differential gene expression(DEG)upon high-temperature *** found that a large number of genes are coregulated by PIF4 and HLS1,especially genes involved in plant growth or defense ***,we found that HLS1 interacts with PIF4 to form a regulatory module and that,among the HLS1-PIF4-coregulated genes,27.7%are direct targets of *** also identified 870 differentially alternatively spliced genes(DASGs)in wild-type plants under high ***,more than half of these DASG events(52.4%)are dependent on both HLS1 and PIF4,and the spliceosome-defective mutant plantsexhibit a hyposensitive response to high temperature,indicating that DASGs are required for *** comparative analyses showed that the HLS1/PIF4-coregulated DEGs and DASGs exhibit almost no overlap,suggesting that high temperature triggers two distinct strategies to control plant responses and *** together,these results demonstrate that the HLS1-PIF4 module precisely controls both transcriptional and posttranscriptional regulation during plant thermomorphogenesis.

关键词： PIF4 HLS1 transcription alternative splicing thermomorphogenesis

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