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Chemical Research in Chinese Universities 2012年第4期28卷 614-619页

作者： LI Jun-fenl SHI Wen-tao HAN Xiu-ying DONG Chuan choi martin m.f. School of Chemistry and Chemical Engineering Research Center of Environmental Science and Engineering Shanxi UniversityTaiyuan 030006P.R.China Department of Chemistry Hong Kong Baptist UniversityHong KongP.R.China

The interaction of calf thymus DNA（ctDNA） with berberine（Ber） was systematically investigated via UV-Vis,fluorescence and phosphorescence spectroscopies in aqueous solution and on solid *** very weak fluorescence intensity of Ber at 525 nm in aqueous solution can be greatly enhanced by *** UV-Vis spectrum shows that Ber could bind with DNA by *** addition,strong fluorescence of Ber alone could be observed on filter paper substrate and can be quenched by ctDNA effectively,and the increase of fluorescence polarization of Ber on the filter paper implies the intercalation *** emits phosphorescence at 619 nm in the presence of thallium（I） *** lifetime of Ber increased from 38.4 ms to 43.4 ms with the increase of *** increase of lifetime is possibly attributed to the increase of rigidity of Ber after its intercalating into the ctDNA base *** explanation is also augmented by the anionic quenching *** behaves as a typical intercalating agent into *** intrinsic binding constant between Ber and ctDNA is（1.84±0.12）×10^4 L/mol and n=0.16.

关键词： Berberine Calf thymus DNA UV-Vis spectroscopy Luminescence Interaction

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： Jens müller Sebastian Leonow Johannes Schulz Christian Hansen martin monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier

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Journal of Energy Chemistry 2024年第5期92卷 296-310页

作者： Benjamin fleiß Juraj Priscak martin Hammerschmid Josef fuchs Stefan müller Hermann Hofbauer Institute of Chemical Environmental and Bioscience EngineeringTU WienVienna1060 ViennaAustria BEST–Bioenergy and Sustainable Technologies GmbH Graz8010 StyriaAustria

Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate *** this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of *** commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid *** oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural *** determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was *** synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were *** techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic *** synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling *** comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.

关键词： Chemical looping combustion BECCS Techno-economic assessment CO_(2)capture costs Oxygen carrier development Synthetic materials Ilmenite

RANKL inhibition reduces lesional cellularity and Gαs variant expression and enables osteogenic maturation in fibrous dysplasia

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Bone Research 2024年第1期12卷 165-179页

作者： Luis f.de Castro Jarred m.Whitlock Zachary michel Kristen Pan Jocelyn Taylor Vivian Szymczuk Brendan Boyce Daniel martin Vardit Kram Rebeca Galisteo Kamran melikov Leonid V.Chernomordik michael T.Collins Alison m.Boyce Skeletal Disorders and mineral Homeostasis Section National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMDUSA Section on membrane Biology Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA metabolic Bone Disorders Unit National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMDUSA Department of Plastic and Reconstructive Surgery The Johns Hopkins Medical InstitutionsBaltimoreMDUSA Department of Pathology and Laboratory medicine University of Rochester Medical CenterRochesterNYUSA NIDCR Genomics and Computational Biology Core National Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMDUSA

fibrous dysplasia(fD)is a rare,disabling skeletal disease for which there are no established *** evidence supports inhibiting the osteoclastogenic factor receptor activator of nuclear kappa-B ligand(RANKL)as a potential treatment *** this study,we investigated the mechanisms underlying RANKL inhibition in fD tissue and its likely indirect effects on osteoprogenitors by evaluating human fD tissue pre-and post-treatment in a phase 2 clinical trial of denosumab(NCT03571191)and in murine in vivo and ex vivo preclinical *** analysis of human and mouse tissue demonstrated increased osteogenic maturation,reduced cellularity,and reduced expression of the pathogenic Gαs variant in fD lesions after RANKL *** sequencing of human and mouse tissue supported these *** interaction between osteoclasts and mutant osteoprogenitors was further assessed in an ex vivo lesion model,which indicated that the proliferation of abnormal fD osteoprogenitors was dependent on *** results from this study demonstrated that,in addition to its expected antiosteoclastic effect,denosumab reduces fD lesion activity by decreasing fD cell proliferation and increasing osteogenic maturation,leading to increased bone formation within *** findings highlight the unappreciated role of cellular crosstalk between osteoclasts and preosteoblasts/osteoblasts as a driver of fD pathology and demonstrate a novel mechanism of action of denosumab in the treatment of bone disease.

关键词： dysplasia treatment finding

Recent Developments in metallic Degradable micromotors for Biomedical and Environmental Remediation Applications

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Nano-micro Letters 2024年第3期16卷 1-35页

作者： Sourav Dutta Seungmin Noh Roger Sanchis Gual Xiangzhong Chen Salvador Pané Bradley J.Nelson Hongsoo choi Department of Robotics and mechatronics Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea DGIST‑ETH microrobotics Research Center DGISTDaegu 42988Republic of Korea multi‑Scale Robotics Lab Institute of Robotics and Intelligent SystemsETH Zurich8092 ZurichSwitzerland Institute of Optoelectronics State Key Laboratory of Photovoltaic Science and TechnologyShanghai Frontiers Science Research Base of Intelligent Optoelectronics and PerceptionFudan UniversityShanghai 200433People’s Republic of China

Synthetic micromotor has gained substantial attention in biomedicine and environmental ***-based degradable micromotor composed of magnesium(mg),zinc(Zn),and iron(fe)have promise due to their nontoxic fuel-free propulsion,favorable biocompatibility,and safe excretion of degradation products Recent advances in degradable metallic micromotor have shown their fast movement in complex biological media,efficient cargo delivery and favorable biocompatibility.A noteworthy number of degradable metal-based micromotors employ bubble propulsion,utilizing water as fuel to generate hydrogen *** novel feature has projected degradable metallic micromotors for active in vivo drug delivery *** addition,understanding the degradation mechanism of these micromotors is also a key parameter for their design and *** propulsion efficiency and life span govern the overall performance of a degradable metallic *** we review the design and recent advancements of metallic degradable ***,we describe the controlled degradation,efficient in vivo drug delivery,and built-in acid neutralization capabilities of degradable micromotors with versatile biomedical ***,we discuss micromotors’efficacy in detecting and destroying environmental ***,we address the limitations and future research directions of degradable metallic micromotors.

关键词： magnesium Zinc Iron Biodegradable microrobot Biomedical Environmental

Haplotype-based phylogenetic analysis and population genomics uncover the origin and domestication of sweetpotato

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molecular Plant 2024年第2期17卷 277-296页

作者： mengxiao Yan ming Li Yunze Wang Xinyi Wang m-Hossein moeinzadeh Dora G.Quispe-Huamanquispe Weijuan fan Yijie fang Yuqin Wang Haozhen Nie Zhangying Wang Aiko Tanaka Bettina Heider Jan f.Kreuze Godelieve Gheysen Hongxia Wang martin Vingron Ralph Bock Jun Yang Shanghai Key Laboratory of Plant functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai 201602China College of Life Sciences Chongqing Normal UniversityChongqing 401331China Biotechnology and Nuclear Technology Research Institute Sichuan Academy of Agricultural SciencesChengdu 610061China College of Life Sciences Shanghai Normal UniversityShanghai 200234China Department of Computational molecular Biology Max Planck Institute for Molecular GeneticsIhnestraBe 63-7314195 BerlinGermany Department of Biotechnology Ghent University9000 GhentBelgium Guangdong Provincial Key Laboratory of Crops Genetics and Improvement Crop Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China Graduate School of Bioagricultural Sciences Nagoya UniversityChikusaNagoya 464-8601Japan international Potato Center(CIP) LimaPeru CAS Center for Excellence of molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China max-Planck-Institut fur molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany

The hexaploid sweetpotato(lpomoea batatas)is one of the most important root crops ***,its genetic origin remains controversial,and its domestication history remains *** this study,we used a range of genetic evidence and a newly developed haplotype-based phylogenetic analysis to identify two probable progenitors of *** diploid progenitor was likely closely related to lpomoea ae-quatoriensis and contributed the B,subgenome,IbT-DNA2,and the lineage 1 type of chloroplast genome to *** tetraploid progenitor of sweetpotato was most likely *** 4x,which donated the B2 subgenome,IbT-DNA1,and the lineage 2 type of chloroplast *** most likely originated from reciprocal crosses between the diploid and tetraploid progenitors,followed by a subsequent whole-genome *** addition,we detected biased gene exchanges between the subgenomes;the rate of B,to B2 subgenome conversions was nearly three times higher than that of B2 to B subgenome *** analyses revealed that genes involved in storage root formation,maintenance of genome stabil-ity,biotic resistance,sugar transport,and potassium uptake were selected during the speciation and domestication of *** study sheds light on the evolution of sweetpotato and paves the way forimprovementofthiscrop.

关键词： sweetpotato origin gene conversion domestication IbT-DNA HPA

Photoinduced Radical-Ionic Transfer of Various Chlorofluorocarbons to Alkenes from Oxime-Based Surrogates

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CCS Chemistry 2024年第5期6卷 1222-1230页

作者： Jinghui Zhang muliang Zhang martin Oestreich Institut für Chemie Technische Universität Berlin10623 Berlin Hefei National Laboratory for Physical Sciences at the microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026

functional-group-transfer strategies that avoid the use of unsustainable chemicals are attractive for the development of green ***(CfCs)not only contribute to the depletion of the stratospheric ozone layer,but their gaseous nature also poses a serious threat in scientific ***,the design of effective and sustainable alternatives to CfCs is highly ***,a practical CfC transfer platform.f.r the addition of both a fluoroalkyl group and a chlorine substituent across alkenes by a photomediated redox-neutral manifold using bench-stable and easy-to-handle oxime-based surrogates is *** distinct reactivity of these tunable reagents allows for their single-electron reduction to trigger fragmentation driven by benzonitrile formation and loss of carbon *** other fragments released in that step,namely an electrophilic fluoroalkyl radical and a nucleophilic chloride anion,are subsequently transferred onto alkenes by a radical-ionic mechanism to deliver the desired chlorofluorocarbon products.

关键词： alkenes chlorofluorocarbons functionalgroup transfer radical-ionic crossover photoredox catalysis

fluorescence quenching method for the determination of catechol with gold nanoparticles and tyrosinase hybrid system

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Chinese Chemical Letters 2010年第3期21卷 346-348页

作者： martin m.f.choi Department of Chemistry Hong Kong Baptist University

The determination method of catechol by fluorescence quenching was *** assay was based on the combination of the unique property of gold nanoparticles with tyrosinase enzymatic *** the presence of tyrosinase,the fluorescence of gold nanoparticles was quenched by catechol which can be employed to detect *** the optimal conditions,a linear range 5.0×10^(-7)-1.0×10^(-3) mol L^(-1) and a detection limit 1.0×10^(-7) mol L^(-1) of catechol were obtained.o-Quinone intermediate produced...

关键词： Gold nanoparticles Tyrosinase Catechol fluorescence quenching

An ethanol biosensor based on a bacterial cell-immobilized eggshell membrane

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Chinese Chemical Letters 2012年第4期23卷 481-483页

作者： Guang ming Wen Shao min Shuang Chuan Dong martin m.f.choi School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan 030006China Research Center of Environmental Science and Engineering Shanxi UniversityTaiyuan 030006China Department of Chemistry Hong Kong Baptist UniversityHong KongChina

An ethanol biosensor was fabricated based on a methylobacterium organophilium-immobilized eggshell membrane and an oxygen（O2） electrode.A linear response for ethanol was obtained in the range of 0.050-7.5 mmol/L with a detection limit of 0.025 mmol/L（S/N= 3） and a *** 2.1%.The response time was less than 100 s at room temperature and ambient pressure. The optimal loading of bacterial cells on the biosensor membrane is 40 mg（wet weight）.The optimal working conditions for the microbial biosensor are pH 7.0 phosphate buffer（50 mmol/L） at 20-25℃.The interference test,operational and storage stability of the biosensor are studied in ***,the biosensor is applied to determine the ethanol contents in various alcohol samples and the results are comparable to that obtained by gas chromatographic method and the results are *** proposed biosensor provides a convenient,simple and reliable method to determine ethanol content in alcoholic drinks.

关键词： Oxygen electrode methylobacterium organophilium Wine microbial biosensor Ethanol Eggshell membrane

Typology and Agroecology of Agroecosystems in Vegetation Dynamics in the Ecotones of the mbam and Inoubou

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Open Journal of forestry 2024年第1期14卷 42-66页

作者： Alex Bruno Dong Etchike Lucie félicité Temgoua Bertine Tiokeng marie Caroline momo Solefack martin Benoit Ngassoum Pierre marie mapongmetsem Laboratory of Applied Botany Faculty of Sciences of the University of Dschang Dschang Cameroon Department of forestry Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon National School of Agro-Industrial Sciences of the University of Ngaoundéré Ngaoundéré Cameroon Laboratory of Biodiversity and Sustainable Development of the University of Ngaoundéré Ngaoundéré Cameroon

Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems of Central and South Cameroon, few have come out contribution of the structure of these traditional systems in the dynamics of the vegetation of these forest-savannah ecotones. The present contribution has the overall objective of demonstrating the structural efficiency of agroforests the dynamics of ecotone vegetation, but also in the conservation of biodiversity. To do this, a participatory analysis was carried out with 56 farmers distributed in the five villages of makénéné. Botanical inventories supplemented socio-economic household surveys. The data collected was subjected to various analyzes (univariate test, analysis of variance, multivariate test, PCA, CAH). The results reveal that 55.2% of agroforests are less than 15 years old and those with an area greater than 1500 m2 predominate (33%). They are mainly young with generally small surface areas. The horizontal structure reveals that the largest diameter classes are those of [20 - 30 cm[ and [10 - 20 cm[ with a very low rate of basal area. Agroforests with trees over 10 m high are dominant in five villages of makénéné. Two types of structural profiles characterize the agroforestry flora of the area, namely intensive pluristratified home gardens on savannah and intensive pluristratified agroforests under forest-savannah transition vegetation. Principal Component Analysis (PCA) and Ascending Hierarchical Clustering (HAC) show three Agroforest Clusters each. The PCA distribution reveals that woody biomass (Y) is strongly correlated with tree diameter (DBH) and significantly with height (Cluster 2). The age (AAG) (Cluster 1) of these agroforests, on the other hand, remains independent of the density (DST) of these trees (Cluster 3). The agroforests in the Nyokon, Carrière and mocksud vil

关键词： Agroforests Agroecosystem Center Cameroon Dynamics Agroecology Typology