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Molecular rotor based on an oxidized resorcinarene

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Organic Chemistry Frontiers 2022年第1期9卷 39-50页

作者： Daniel T.payne Jan Labuta Zdeněk Futera Václav Březina Lenka Hanyková Mandeep K.Chahal jonathan p.hill International Center for Materials Nanoarchitectonics National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan bInternational Center for Young Scientists National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan Institute of physics Faculty of ScienceUniversity of South BohemiaBranišovská1760ČeskéBudějovice 37005Czech Republic Faculty of Mathematics and physics Charles UniversityV Holešovičkách 218000 Prague 8Czech Republic

Molecular rotors are an important class of dynamic molecules which have been studied not only for their possible uses as components of molecular machines but also because of potential applications as probes of local viscosity in biological media,especially self-assembled *** the former,factors affecting rotational motility are critical while for the latter the rotor activity must be complexed with an output signal(often fluorescence)for reporting of local *** single stator-double rotor activity of an oxidized resorcinarene(fuchsonarene)macrocycle containing unsaturated hemiquinonoid groups at its meso positions was *** contain two hemiquinonoid substituents at diagonally-opposed meso-positions with two electron rich phenol groups at the remaining meso-positions between the hemiquinonoid *** meso-substituents are in proximity at one side of the resorcinarene macrocycle(so-called rccc-type isomer)with rotational activity of the phenol *** rates of the phenol moieties can be controlled by varying temperature,solvent polarity and acidity of the medium of study with rotation being thermally activated in neutral and acidic media and tunable in the range from 2 s^(−1) to 20000 s^(−1).Experimental and computational data indicate that rotation of the mobile phenol meso-substituents is remotely affected by interactions with acidic solvents at the carbonyl CvO groups of macrocyclic acetyloxy groups,which occurs with the emergence of a lower energy electronic absorption band whose intensity is correlated with both the acidity of the medium and the rotation rate of the phenol ***-dependent DFT calculations suggest that the low energy band is due to a molecular conformational adjustment affecting electronic conjugation caused by strong interaction of macrocyclic acetyloxy carbonyl groups with the acid *** work presents a molecular mechanical model for estimating solution acidity a

关键词： substituent rotation oxidized

A new class of crystalline X-ray induced photochromic materials assembled from anion-directed folding of a flexible cation

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Chinese Chemical Letters 2024年第8期35卷 554-557页

作者： Hong-Jin Liao Zhu Zhuo Qing Li Yoshihito Shiota jonathan p.hill Katsuhiko Ariga Zi-Xiu Lu Lu-Yao Liu Zi-Ang Nan Wei Wang You-Gui Huang CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Xiamen Key Laboratory of Rare Earth photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen 361021China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China Institute for Materials Chemistry and Engineering Kyushu UniversityFukuoka 819-0395Japan World premier International(WpI)Center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)Ibaraki 305-0044Japan

Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic ***,a new rational strategy of anion-directed fold-ing a flexible cation(H_(2)imb)^(2+)((H_(2)imb)^(2+)=di-protonated 2,3-bis(imidazolin-2-yl)-2,3-dimethylbutane)has been ***-donating Cl−and(ZnCl4)2−are used to direct folding a flexible electron-deficient(H_(2)imb)^(2+)*** complexes(H_(2)imb)(NO_(3))2(1),(H_(2)imb)Cl2·H_(2)O(2),and(H_(2)imb)ZnCl4(3)have been synthesized in which(H_(2)imb)^(2+)crystallize in an anti-conformation,88.8°-gauche,and 51.8°-gauche,*** contrary to X-ray silent complex 1,X-ray induced photochromism has been achieved in both complex 2 and *** intermolecular charge-transfer mechanism has been elucidated and the anion directed folding of(H_(2)imb)^(2+)has been validated to be critical to yield colored long-lived charge-separated states.

关键词： Supramolecular photochromic X-ray induced Anion-directed folding Electron-deficient viologens

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功能光电分子的表面分散与STM研究

功能光电分子的表面分散与STM研究

Therapeutic mechanisms and routes of delivery of mesenchymal stem cells in veterinary medicine:A point of view

中国真空学会2012学术年会

作者：邝艳敏耿锋张尧朱三娥 André Gourdon jonathan p.hill 王官武董振超中国科学技术大学微尺度物质科学国家实验室

二萘嵌苯分子由于具有高荧光效率等优良的光电性质,在电子和光电元件中有着广泛的应用。化学修饰的二萘嵌苯分子衍生物由于具有新的光电特性在纳米光电子学和纳米电子学领域也得到了广泛的研究。在本文中,我们在超高真空环境下利用闪热...

二萘嵌苯分子由于具有高荧光效率等优良的光电性质,在电子和光电元件中有着广泛的应用。化学修饰的二萘嵌苯分子衍生物由于具有新的光电特性在纳米光电子学和纳米电子学领域也得到了广泛的研究。在本文中,我们在超高真空环境下利用闪热脱吸附方法5将具有四脚架结构的二萘嵌苯分子衍生物沉积到金属衬底上,并利用STM对吸附的分子进

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BIOCELL 2022年第5期46卷 1173-1176页

作者： AMANDA BARACHO TRINDADE hill jonathan EDWIN BARACHO TRINDADE hill Centro Universitário Max planck IndaiatubaBrazil CellTech-Stem Cell Technologies CampinasBrazil

Mesenchymal stem cells(MSCs)represent an important tool in veterinary regenerative medicine due to their ability to home to injury sites and secrete molecules that regulate niches into regenerative *** cell therapy depends on many factors,including choice of administration route and application of understanding of cell potency and their therapeutic *** this point of view,the authors leverage the tumultuous history of the field to demonstrate the need for clinicians to continually update themselves as new discoveries are made in order to avoid misalignments in the future,especially regarding administration routes and dose frequency,as well as to explore recent insights into MSC plasticity,therapeutic mechanisms,and cell delivery systems.

关键词： Cell therapy Application Injection pharmacodynamics pharmacokinetics

A Comparative Analysis of Quantitative Metrics of Root Architecture

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plant phenomics 2021年第1期3卷 65-85页

作者： Harini Rangarajan jonathan p.Lynch Department of plant Science The Pennsylvania State UniversityUniversity ParkPA 16802USA

High throughput phenotyping is important to bridge the gap between genotype and *** methods used to describe the phenotype therefore should be robust to measurement errors,relatively stable over time,and most importantly,provide a reliable estimate of elementary phenotypic *** this study,we use functional-structural modeling to evaluate quantitative phenotypic metrics used to describe root architecture to determine how they fit these *** results show that phenes such as root number,root diameter,and lateral root branching density are stable,reliable measures and are not affected by imaging method or *** aggregating multiple phenes such as total length,total volume,convex hull volume,and bushiness index estimate different subsets of the constituent phenes;they however do not provide any information regarding the underlying phene *** of phene aggregates are not unique representations of underlying constituent phenes:multiple phenotypes having phenes in different states could have similar aggregate *** growth angle is an important phene which is susceptible to measurement errors when 2D projection methods are *** that aggregate phenes which are complex functions of root growth angle and other phenes are also subject to measurement errors when 2D projection methods are *** results support the hypothesis that estimates of phenes are more useful than metrics aggregating multiple phenes for phenotyping root *** propose that these concepts are broadly applicable in phenotyping and phenomics.

关键词： aggregate projection estimates

Variant selection in stationary shoulder friction stir welded Ti-6Al-4V alloy

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Journal of Materials Science & Technology 2018年第1期34卷 198-208页

作者： Xiaoqing Jiang Bradley p.Wynne jonathan Martin Engineering Research Center of Advanced Manufacturing Technology for Automotive Structural parts Ministry of Education College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Department of Materials Science and Engineering The University of Sheffield The Welding Institute Granta Park

Stationary shoulder friction stir welding of Ti-6Al-4V of 7 mm thickness was conducted with varying welding speeds and rotation speeds. Variant selection analysis was carried out based on the inherited α phase texture and the reconstructed 13 phase texture. The weld surfaces became significantly smoother with increasing welding speed and decreasing rotation speed. Heat input decreased greatly with increased welding speed and it decreased slightly with decreased rotation speed. The orientation relationship between the prior 13 grains was measured based on the reconstructed electron backscattered diffraction （EBSD） data. Weak Variant selection has occurred in all the welds because most of the prior 13 grains did not share { 110} poles. Strong links between crystal orientation of the prior 13 grains and hardness have been found.

关键词： Stationary shoulder friction stir welding Texture Variant selection Hardness

Accurate and scalable graph neural network force field and molecular dynamics with direct force architecture

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npj Computational Materials 2021年第1期7卷 650-658页

作者： Cheol Woo park Mordechai Kornbluth jonathan Vandermause Chris Wolverton Boris Kozinsky jonathan p.Mailoa Robert Bosch Research and Technology Center CambridgeMA 02139USA Northwestern University EvanstonIL 60208USA Harvard School of Engineering and Applied Sciences CambridgeMA 02138USA

Recently,machine learning(ML)has been used to address the computational cost that has been limiting ab initio molecular dynamics(AIMD).Here,we present GNNFF,a graph neural network framework to directly predict atomic forces from automatically extracted features of the local atomic environment that are translationally-invariant,but rotationally-covariant to the coordinate of the *** demonstrate that GNNFF not only achieves high performance in terms of force prediction accuracy and computational speed on various materials systems,but also accurately predicts the forces of a large MD system after being trained on forces obtained from a smaller ***,we use our framework to perform an MD simulation of Li7p3S11,a superionic conductor,and show that resulting Li diffusion coefficient is within 14%of that obtained directly from *** high performance exhibited by GNNFF can be easily generalized to study atomistic level dynamics of other material systems.

关键词： neural AIMD dynamics

In situ measurement of ECM rheology and microheterogeneity in embedded and overlaid 3D pancreatic tumor stroma co-cultures via passive particle tracking

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Journal of Innovative Optical Health Sciences 2017年第6期10卷 26-34页

作者： Dustin p.Jones William Hanna Gwendolyn M.Cramer jonathan p.Celli Department of physics University of Massachusetts Boston Boston MA 02215USA

Tumor growth is regulated by a diverse set of extraellular infuences,including paracrine crosstalk with stromal partners,and biophysical interactions with surrounding cells and *** elucidating the role of physical force and the mechanical properties of the extracellular matrix(ECM)itself as regulators of tumor growth and invasion have been greatly catalyzed by the use of in ritro three-dimensional(3D)tumor *** systems provide the ability to systematically isolate,manipulate,and evaluate impact of stromal components and extracellular mechanics in a platform that is both conducive to imaging and biologically ***,recognizing that mechanoregulatory crosstalk is bi-directional and fully utilizing these models requires complementary methods for in situ measurements of the local mechanical ***,in 3D tumor/fbroblast co-culture models of pancreatic canocer,a discase characterized by its prominent stromal involvement,we evaluate the use of particle-tracking microrhoology to probe dynamic mechanical *** videos of fuorescently labeled polystyrene micro-spheres embedded in ollagen I ECM,we measure spatiotemporal changes in the Brownian motion of probes to report local ECM shear modulus and *** approach reveals st ffening of collagen in fibroblast co-cultures relative to cultures with cancer cells only,which exhibit degraded ECM with heterogeneous *** further show that these effects are dependent on culture geometry with contrast ing behavior for embedded and overlay *** addition to potential application to screening stroma targeted therapeutics,this work also provides insight into how the compoition and plating geometry impact the mechanical propertios of 3D cell cultures that are increasingly widey used in cancer biology.

关键词： Microrheology 3D tumor models matrix remodeling mechanobiology stromal depletion

Above-ground woody biomass allocation and within tree carbon and nutrient distribution of wild cherry(prunus avium L.)-a case study

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Forest Ecosystems 2016年第2期3卷 138-152页

作者： Christopher Morhart jonathan p. Sheppard Johanna K. Schuler Heinrich Spiecker Chair of Forest Growth and Dendroecology Albert-Ludwigs-University Freiburg Tennenbacher Str. 4 D 79106 Freiburg Germany

Background： The global search for new ways to sequester carbon has already reached agricultural lands. Such land constitutes a major potential carbon sink. The production of high value timber within agroforestry systems can facilitate an in-situ carbon storage function. This is followed by a potential long term ex- situ carbon sinkwithin long lasting products such as veneer and furniture. For this purpose wild cherry （prunus avium L.） is an interesting option for middle Europe, yielding high prices on the timber market. Methods： A total number of 39 wild cherry were sampled in 2012 and 2013 to assess the leafless above ground biomass. The complete trees including stem and branches were separated into 1 cm diameter classes. Wood and bark from sub-samples were analysed separately and nutrient content was derived. Models for biomass estimation were constructed for all tree compartments. Results： The smallest diameter classes possess the highest proportion of bark due to smaller cross sectional area. Tree boles with a greater amount of stem wood above 10 cm in diameter will have a more constant bark proportion. Total branch bark proportion also remains relatively constant above *** measurements of 8 cm. A balance is evident between the production of new branches with a low diameter and high bark proportion offset by the thickening and a relative reduction in bark proportion in larger branches. The results show that a single tree with an age of 17 and 18 years can store up to 85 kg of carbon within the aboveground biomass portion, an amount that will increase as the tree matures. Branches display greater nutrient content than stem sections per volume unit which can be attributed to a greater bark proportion. Conclusions： Using the derived models the carbon and the nutrient content of above-ground woody biomass of whole trees can be calculated. Suggested values for carbon with other major and minor nutrients held within relatively immature trees strongly supports the id

关键词： Carbon sequestration Biomass Bark Branch Stem Nutrient content AIIometry Agroforestry