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Synthesis of Silsesquioxane Cages from Phenyl-cis-tetrol, 1,3-Divinyltetraethoxydisiloxane and Cyclopentyl Resins

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Chemical Research in Chinese Universities 2004年第4期20卷 433-436页

作者： alan R. Bassindale peter G. Taylor Department of Chemistry Open UniversityDepartment of Chemistry Open University Walton Hall Milton Keynes MK7 6AA UKWalton Hall Milton Keynes MK7 6AA UK

The synthesis of T_8, T_ 10 and T_ 12 silsesquioxane cages from a range of starting materials: phenyl-cis-tetrol, 1,3-divinyltetraethoxydisiloxane and cyclopentyl T resins by using tetra n-butylammonium fluoride(TBAF) as the catalyst is described in this paper. The reaction yields obtained viathe current route are better compared to those viathe literature routes. Some of the cage compounds have been characterized by X-ray crystallography.

关键词： Synthesis Silsesquioxane cage Phenyl-cis-tetrol 1,3-Divinyltetraethoxydisiloxane Cyclopentyl T resin

ELECTROACTIVE AND NANOSTRUCTURED POLYMERS AS SCAFFOLD MATERIALS FOR NEURONAL AND CARDIAC TISSUE ENGINEERING

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Chinese Journal of Polymer Science 2007年第4期25卷 331-339页

作者： Paul Bidez Elizabeth Guterman-Tretter alan G. MacDiarmid peter I. Lelkes 危岩 School of Biomedical Engineering Science & Health SystemsDrexel UniversityPhiladelphiaPA 19104USA School of Biomedical Engineering Science & Health SystemsDrexel UniversityPhiladelphiaPA 19104USA Department of ChemistryDrexel UniversityPhiladelphiaPA 19104USA Department of Chemistry University of PennsylvaniaPhiladelphiaPA 19104USA

Conducting polymer, polyaniline （PANI）, has been studied as a novel electroactive and electrically conductive material for tissue engineering applications. The biocompatibility of the conductive polymer can be improved by （i） covalently grafting various adhesive peptides onto the surface of prefabricated conducting polymer films or into the polymer structures during the synthesis, （ii） co-electrospinning or blending with natural proteins to form conducting nanofibers or films, and （iii） preparing conducting polymers using biopolymers, such as collagen, as templates. In this paper, we mainly describe and review the approaches of covalently attaching oligopeptides to PANI and electrospinning PANI-gelatin blend nanofibers. The employment of such modified conducting polymers as substrates for enhanced cell attachment, proliferation and differentiation has been investigated with neuronal PC-12 cells and H9c2 cardiac myoblasts. For the electrospun PANI- gelatin fibers, depending on the concentrations of PANI, H9c2 cells initially displayed different morphologies on the fibrous substrates, but after one week all cultures reached confluence of similar densities and morphologies. Furthermore, we observed, that conductive PANI, when maintained in an aqueous physiologic environment, retained a significant level of electrical conductivity for at least 100 h, even though this conductivity was decreasing over time. Preliminary data show that the application of micro-current stimulates the differentiation of PC-12 cells. All the results demonstrate the potential for using PANI as an electroactive polymer in the culture of excitable cells and open the possibility of using this material as an electroactive scaffold for cardiac and/or neuronal tissue engineering applications that require biocompatibility of conductive polymers.

关键词： Polyaniline Conductive polymer Biocompatibility Tissue engineering.

The new COVID-19 poor and the neglected tropical diseases resurgence

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Infectious Diseases of Poverty 2021年第1期10卷 1-3页

作者： peter J.Hotez alan Fenwick David Molyneux Department of Pediatrics Texas Children's Hospital CenterforVaccine DevelopmentNational School of Tropical MedicineBaylor College of MedicineHoustonTXUSA Department of Molecular Virology and Microbiology Texas Children's Hospital Center for Vaccine DevelopmentNational School of Tropical MedicineBaylor College of MedicineHoustonTXUSA Hagler Institute for Advaneed Study at Texas A&M University College StationTXUSA Department of Biology Baylor UniversityWacoTXUSA James A Baker III Institute of Public Policy Rice UniversityHoustonTXUSA Scowcroft Institute of International Affairs Bush School of Government and Public ServiceTexas A&M UniversityCollege StationTXUSA School of Public Health Faculty of MedicineImperial College Lon don LondonUK. Centre for Neglected Tropical Diseases Liverpool School ofTropical MedicineLiverpoolUK.

More than 100 million people are facing a return to extreme poverty because of coronavirus disease 2019(COVID-19),while new estimates suggest that three nations—India,Nigeria,and the Democratic Republic of the Congo-may suffer the greatest economic *** findings will have profound consequences in terms of our ability to control or eliminate the most widely prevalent neglected tropical diseases.

关键词： neglected tropical consequences

The challenges of developing an open source, standards-based technology stack to deliver the latest UK climate projections

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International Journal of Digital Earth 2012年第1期5卷 43-62页

作者： Ag Stephens Philip James David Alderson Stephen Pascoe Simon Abele alan Iwi peter Chiu The British Atmospheric Data Centre DidcotUK School of Civil Engineering and Geosciences Newcastle UniversityNewcastle-Upon-TyneUK

To improve the understanding of local and regional effects of climate change,the UK government supported the development of new climate *** Met Office Hadley Centre produced a sophisticated set of probabilistic projections for future *** paper discusses the design and implementation of an interactive website to deliver those projections to a broad user *** interface presents complex data sets,generates on-the-fly products and schedules jobs to an offline weather generator capable of outputting gigabytes of data in response to a single request.A robust and scalable physical architecture was delivered through significant use of open source technologies and open standards.

关键词： geoinformatics digital earth climate change geospatial science geospatial data integration

Zebrafish Wnt9b Patterns the First Pharyngeal Arch into D-I-V Domains and Promotes Anterior-Medial Outgrowth

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American Journal of Molecular Biology 2015年第3期5卷 57-83页

作者： Henry Wells Jackson Divakar Prakash Mark Litaker Tracie Ferreira peter A. jezewski Department of Genetics University of Alabama at Birmingham Birmingham USA University of Alabama at Birmingham School of Dentistry Institute of Oral Health Research Birmingham USA Department of Clinical and Community Sciences University of Alabama at Birmingham School of Dentistry Birmingham USA Department of Bioengineering University of Massachusetts Dartmouth Dartmouth MA USA Department of Pediatric Dentistry University of Alabama at Birmingham School of Dentistry Birmingham AL USA

Disrupted morphogenesis and growth of the embryonic maxillary jaw lead to oral facial clefting in humans (OFC) and result in an incompletely formed secondary mouth and face. A requirement for Wnt signaling and Wnt9b in particular are postulated in the etiology of OFC from association studies in humans and from animal models. Loss of murine Wnt9b leads to reduced upper jaw (maxillary) outgrowth and OFC, though the signaling architecture leading to this phenotype is poorly understood. Previous murine Wnt9b studies largely overlooked cranial neural crest cell (CNCC) patterning events and instead focused on later events during fusion of facial prominences. Using zebrafish and a morpholino-mediated knockdown approach, we demonstrate functional requirements for Wnt9b signaling during two crucial stages of facial development: 1) CNCC patterning into Dorsal-Intermediate-Ventral (D-I-V) domains;and 2) facial outgrowth during the primary to secondary mouth transition (PM to SM). Zebrafish embryos deficient for Wnt9b (Wnt9b morphants) exhibit an open bite with fused jaw joints as well as a flat face. Open bite and jaw joint fusion in Wnt9b morphants phenocopies characteristics of edn1 pathway is mutant zebrafish with disrupted D-I-V patterning of CNCC. Expression studies show Wnt9b morphants exhibit perturbed expression of edn1 signaling targets including dlx2a, jag1b, and msxe, consistent with disrupted CNCC patterning. Wnt9b morphant upper jaws have stunted outgrowth reminiscent of murine Wnt9b mutants and Wnt9b morphant skulls phenocopy the broad class of foreshortened skull zebrafish mutants known as hammerheads. Wnt9b morphants show upregulated expression of pitx2a after the opening of the primary mouth and disrupted expression of Wnt5b which is consistent with disrupted chondrocyte stacking. Strong upregulation of dorsal mesodermal frzb expression in the prechordal plate of Wnt9b morphants suggests a role for Wnt9b in primary mouth induction or maintenance. Collectively

关键词： Cleft Morphogenesis Patterning Cranial Neural Crest Cell Pharyngeal Arch Primary/Secondary Mouth

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北美有轨电车的回归

国外铁道机车与动车 2023年第1期 25-27页

作者： [美]David peter alan 张建平(译) 不详

上个世纪,美国和加拿大客运列车的保有量下滑,有轨电车几近消失。如今,随着技术的进步以及新产品的研发,北美有轨电车有望回归。

关键词：北美有轨电车轻轨

Installation and operational effects of a HVDC submarine cable in a continental shelf setting: Bass Strait, Australia

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Journal of Ocean Engineering and Science 2016年第4期1卷 337-353页

作者： John Sherwood Scott Chidgey peter Crockett David Gwyther Percival Ho Simon Stewart David Strong Bob Whitely alan Williams School of Life and Environmental Sciences Deakin UniversityWarrnamboolVictoria 3280Australia CEE Consulting 90 Bridge RoadRichmondVictoria 3121Australia Enesar Consulting Pty Ltd 124 Camberwell RdHawthorn EastVictoria 3123Australia DSA Consulting Suite 211620 St Kilda RoadMelbourneVictoria 3004Australia Coffey Natural Systems Pty Ltd 126 Trenerry CrescentAbbotsfordVictoria 3067Australia Marine Research CSIROHobartTasmania 7000Australia Picton Group Pty Ltd 30 Malpas DriveWallingtonVictoria 3222Australia

Despite the many submarine telecommunications and power cables laid world-wide there are fewer than ten published studies of their environmental effects in the refereed *** paper describes an investigation into the effects of laying and operating the Basslink High Voltage Direct Current(HVDC)cable and its associated metallic return cable across Bass Strait in South East *** more than 95%of its length the cable was directly laid into a wet jetted trench given the predominantly soft sediments *** remote video investigations found that within two years all visible evidence of the cable and trench was gone at over a third of the transects at six deep water sites(32-72 m deep).At other deep water transects the residual trench trapped drift material providing habitat for the generally sparsely distributed benthic *** surveys at both of the near shore sites(<15 m deep)on the northern side of the Strait also found the cable route was undetectable after a *** the southern side,where the cable traversed hard basalt rock near shore,it was encased in a protective cast iron half *** studies by divers over 3.5 years demonstrated the colonization of the hard shell by similar species occupying hard substrates elsewhere on the basalt *** field strengths associated with the operating cable were found to be within 0.8%of those predicted from theory with strength dropping rapidly with distance from the *** 20 m the field was indistinguishable from background.

关键词： High Voltage Direct Current Power cable Magnetic field Epibenthos Ecological effects Video survey

Late syn-to post-collisional magmatism in Madagascar:The genesis of the Ambalavao and Maevarano Suites

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Geoscience Frontiers 2019年第6期10卷 2063-2084页

作者： Donnelly B.Archibald alan S.Collins John D.Foden Justin L.Payne peter Holden Théodore Razakamanana Department of Earth Sciences St.Francis Xavier UniversityPhysical Sciences Complex5009 Chapel SquareAntigonishNSB2G 2W5Canada Centre for Tectonics Resources and Exploration(TRaX)Department of Earth SciencesThe University of AdelaideAdelaide 5005SAAustralia Centre for Tectonics Resources and Exploration(TRaX)School of Built and Natural EnvironmentsUniversity of South AustraliaMawson LakesSA5001Australia Research School of Earth Sciences The Australian National UniversityCanberraACT2601Australia Departement des Sciences de la Terre Universitede ToliaraToliara601Madagascar

The East African Orogen involves a collage of Proterozoic microcontinents and arc terranes that became wedged between older cratonic blocks during the assembly of *** Ediacaran-Cambrian Ambalavao and Maevarano Suites in Madagascar were emplaced during the waning orogenic stages and consist of weakly deformed to undeformed plutonic rocks and dykes of mainly porphyritic granite but also gabbro,diorite and charnockite.U-Pb geochronological data date emplacement of the Ambalavao Suite to between ca.580 Ma and 540 Ma and the Maevarano Suite to between ca.537 Ma and522 *** and trace element concentrations are consistent with emplacement in a syn-to postcollisional tectonic setting as A-type(anorogenic) ***(δ^(18)O of 5.27‰-7.45‰) and hafnium(ε(Hf)(t) of-27.8 to-12.3) isotopic data from plutons in the Itremo and Antananarivo Domains are consistent with incorporation of an ancient crustal *** primitive δ^(18)O(5.27‰-5.32‰) andε(Hf)(t)(+0.0 to+0.2) isotopic values recorded in samples collected from the Ikalamavony Domain demonstrate the isotopic variation of basement sources present in the Malagasy *** Hf isotopic composition of Malagasy zircon are unlike more juvenile Ediacaran-Cambrian zircon sou rces elsewhere in the East African Orogen and,as such,Madagascar represents a distinct and identifiable detrital zircon source region in Phanerozoic sedimentary provenance *** together,these data indicate that high-T crustal anatexis,crustal assimilation and interaction of crustal material with mantle-derived melts were the processes operating during magma *** magmatism was coeval with polyphase deformation throughout Madagascar during the amalgamation of Gondwana and magmatism is interpreted to reflect lithospheric delamination of an extensive orogenic plateau.

关键词： Madagascar geology East African orogen Zircon geochronology Zircon oxygen and hafnium isotopes Post-collisional magmatism

Neoproterozoic tectonic geography of the south-east Congo Craton in Zambia as deduced from the age and composition of detrital zircons

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Geoscience Frontiers 2019年第6期10卷 2045-2061页

作者： Brandon L.Alessio alan S.Collins peter Siegfried Stijn Glorie Bert De Waele Justin Payne Donnelly B.Archibald Centre for Tectonics Resources and Exploration(TRaX)Dept of Earth SciencesThe University of AdelaideAdelaideSouth Australia 5005Australia GeoAfrica Prospecting Services cc ErosNamibia SRK Consulting 1/10 Richardson StWest PerthWestern Australia 6005Australia Curtin University of Technology Kent StBentleyWestern Australia 6102Australia Centre for Tectonics Resources and Exploration(TRaX)School of Built and Natural EnvironmentsUniversity of South AustraliaAdelaideSouth Australia 5000Australia St.Francis Xavier University Physical Sciences Complex5009 Chapel SquareAntigonishNova Scotia B2G 2W5Canada

The Southern Irumide Belt(SIB)is an orogenic belt consisting of a number of lithologically varied Mesoproterozoic and Neoproterozoic terranes that were thrust upon each *** belt lies along the southwest margin of the Archaean to Proterozoic Congo Craton,and bears a Neoproterozoic tectonothermal overprint relating to the Neoproterozoic-Cambrian collision between the Congo and Kalahari *** preserves a record of about 500 million years of plate interaction along this part of the Congo *** zircon samples from the SIB were analysed for U-Pb and Lu-Hf isotopes,as well as trace element *** data are used to constrain sediment-source relationships between SIB terranes and other Gondwanan terranes such as the local Congo Craton and Irumide belt and wider afield to Madagascar(Azania)and *** correlations are then used to interpret the Mesoproterozoic to Neoproterozoic affinity of the rocks and evolution of the *** zircon samples from the Chewore-Rufunsa and Kacholola(previously referred to as Luangwa-Nyimba)terranes of the SIB yield zircon U-Pb age populations and evolvedε(Hf)(t)values that are similar to the Muva Supergroup found throughout eastern Zambia,primarily correlating with Ubendian-Usagaran(ca.2.05-1.80 Ga)phase magmatism and a cryptic basement terrane that has been suggested to underlie the Bangweulu Block and Irumide *** data suggest that the SIB was depositionally connected to the Congo Craton throughout the *** more eastern Nyimba-Sinda terrane of the SIB(previously referred to as Petauke-Sinda terrane)records detrital zircon ages andε(Hf)(t)values that correlate with ca.1.1-1.0 Ga magmatism exposed elsewhere in the SIB and Irumide *** ascribe this difference in age populations to the polyphase development of the province,where the sedimentary and volcanic rocks of the Nyimba-Sinda terrane accumulated in extensional basins that developed in the *** deposition wou

关键词： Detrital zircon geochronology Tectonics Hafnium isotopes Zambia Southern irumide belt Irumide belt