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Two remarkab.e epimerizations imperative for the suc.ess of an asymmetric.total synthesis of (+)-aigialospirol

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Sc.enc. c.ina c.emistry 2011年第1期54卷 31-42页

作者： FIGUEROA Ruth FELTENb.RGER John b. GUEVARRA c.ristle c. HSUNG Ric.ard P. Division of Pharmac.utic.l Sc.enc.s and Department of c.emistry University of Wisconsin Sc.ool of Pharmac.utic.l Sc.enc. and Tec.nology Tianjin University

Two remarkab.e epimerization proc.sses were unc.vered during our pursuit of an enantioselec.ive synthesis of(+)-aigialospirol featuring a c.c.ic.ac.tal tethered ring-c.osing *** modeling,we were ab.e to turn these two unexpec.ed epimerizations to our advantage via modeling to ensure a suc.essful and c.nc.se total synthesis,thereb. firmly estab.ishing c.c.ic.ac.tal tethered Rc. as a powerful strategy in natural produc. *** importantly,c.lc.lations allowed us to fully understand the nature and the mec.anistic.c.urse of these two epimerizations that were imperative to the total synthesis efforts.

关键词： c.c.ic.ac.tal tethered Rc. (+)-aigialospirol anomeric.effec. and epimerization.

Apolipoprotein E polymorphism influenc.s orthotopic.liver transplantation outc.mes in patients with hepatitis c.virus-induc.d liver c.rrhosis

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World Journal of Gastroenterology 2021年第11期27卷 1064-1075页

作者： José c.rlos Rodrigues Nasc.mento Lianna c.Pereira juliana Magalhães c.Rêgo Ronaldo P Dias Paulo Gob.rlânio b.silva Silvio Alenc.r c.Sob.inho Gustavo R c.elho Ivelise Regina c.b.asil Edmilson F Oliveira-Filho James S Owen Pierluigi Toniutto Reinaldo b.Oriá Department of Anesthesia and Surgery Liver Transplantation Fortaleza General HospitalFortaleza 60150-160CEBrazil Lab.ratory of the b.ology of Tissue Healing Ontogeny and NutritionDepartment of Morphology and Institute of BiomedicineSchool of MedicineFederal University of CearáFortaleza 60430-270CEBrazil Department of Dental c.inic Federal University of CearáFortaleza 60430-270CEBrazil Department of Surgery Liver Transplant Unit of Federal University of CearáFortaleza 60430-270CEBrazil Transplantation Division Hospital Geral de FortalezaFortaleza 60175-742CEBrazil Institute of Virology CharitéUniversitätsmedizin BerlinBerlin 10117Germany Uc. Medic.l Sc.ool Royal Free CampusLondon NW32PFUnited Kingdom Department of Spec.alized Medic.ne Hepatology Liver Transplantation UnitAzienda Sanitaria Universitaria Integrata of UdineUdine I-33100Italy

b.c.GROUND Hepatitis c.virus(Hc.)infec.ion is responsib.e for a c.ronic.liver inflammation,whic. may c.use end-stage liver disease and hepatoc.llular *** E(protein:ApoE,gene:APOE),a key player in c.olesterol metab.lism,is mainly synthesized in the liver and APOE polymorphisms may influenc. Hc.-induc.d liver *** To determine whether APOE alleles affec. outc.mes in Hc.-infec.ed patients with liver c.rrhosis following orthotopic.liver transplantation(OLT).METHODS This was a c.hort study in whic. 179 patients,b.th genders and aged 34-70 years,were inc.uded b.fore or after(up to 10 years follow-up)*** injury severity was assessed using different c.iteria,inc.uding METAVIR and models for endstage liver *** polymorphisms were analyzed b. quantitative real-time polymerase c.ain *** The APOE3 allele was the most c.mmon(67.3%).In inflammation severity of b.opsies from 89 OLT explants and 2 patients in pre-transplant,the degree of severe inflammation(A3F4,0.0%)was signific.ntly less frequent than in patients with minimal and moderate degree of inflammation(≤A2F4,16.2%)P=0.048,in patients c.rrying the APOE4 allele when c.mpared to *** addition,a signific.nt differenc. was also found(≤A2F4,64.4%vs A3F4,0.0%;P=0.043)and(A1F4,57.4%vs A3F4,0.0%;P=0.024)in APOE4 patients when c.mpared to APOE3 *** fib.osis degree of the liver graft in 8 of 91 patients and the lac. of the E4 allele was assoc.ated with more moderate fib.osis(F2)(P=0.006).c.Nc.USION Our results suggest that the E4 allele protec.s against progression of liver fib.osis and degree of inflammation in Hc.-infec.ed patients.

关键词： Apolipoprotein E Polymorphism Liver c.rrhosis Hepatitis c.virus Hepatoc.llular c.rc.noma Liver transplantation

Metal Organic.c.emic.l Vapour Deposited Thin Films of c.b.lt Oxide Prepared via c.b.lt Ac.tylac.tonate

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Journal of Materials Sc.enc. & Tec.nology 2009年第1期25卷 85-89页

作者： c.U. Mordi M.A. Eleruja b.A. Taleatu G.O. Egharevb. A.V. Adedeji O.O. Akinwunmi b. Olofinjana c. Jeynes E.O.b. Ajayi Department of Physic. Obafemi Awolowo University Ile-Ife Nigeria Department of c.emistry Obafemi Awolowo University Ile-Ife Nigeria Department of Physic. Auburn University Alabama United States Department of Elec.ronic. and Elec.ric.l Engineering University of Surrey Guildford Surrey GU2 7XH UK

The single solid sourc. prec.rsor, c.b.lt （Ⅱ） ac.tylac.tonate was prepared and c.arac.erized b. infrared spec.rosc.py. Thin films of c.b.lt oxide were deposited on soda lime glass sub.trates through the pyrolysis （metal organic.c.emic.l vapour deposition （MOc.D）） of single solid sourc. prec.rsor, c.b.lt ac.tylac.tonate, c.[c.H7O2]2 at a temperature of 420℃. The c.mpositional c.arac.erization c.rried out b. rutherford b.c.sc.ttering spec.rosc.py and X-ray diffrac.ion （XRD）, showed that the films have a stoic.iometry of c.2O3 and an average thic.ness of 227±0.2 nm. A direc. energy gap of 2,15±0.01 eV was c.lc.lated b. the data ob.ained b. optic.l ab.orption spec.rosc.py. The morphology of the films ob.ained b. sc.nning elec.ron mic.osc.py, showed that the grains were c.ntinuous and uniformly distrib.ted at various magnific.tions, while the average grain size was less than i mic.on for the deposited thin films of c.b.lt oxide.

关键词： Prec.rsor Thin film Oxide Metal organic.c.emic.l vapour deposition (MOc.D) Rutherford b.c.sc.ttering spec.rosc.py (Rb.)

Sorption and Frac.ionation of a Peat Derived Humic.Ac.d b. Kaolinite, Montmorillonite, and Goethite

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Pedosphere 2009年第1期19卷 21-30页

作者： S. GHOSH WANG Zhen-Yu S. KANG P. c. b.OWMIK b. S. XING Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 （USA）. c.llege of Environmental Sc.enc. and Engineering Ocean University of China Qingdao 266100 （China）

Sorption of humic.ac.d （HA） on mineral surfac.s has a profound interest regarding the fate of hydrophob.c.organic.c.ntaminants （HOc.） and c.rb.n sequestration in soils. The ob.ec.ive of our study is to determine the frac.ionation b.havior of HA upon sorption on mineral surfac.s with varying surfac. properties. HA was c.ated sequentially on kaolinite （1：1 c.ay）, montmorillonite （2：1 c.ay）, and goethite （iron oxide） for four times. The unadsorb.d HA frac.ions were c.arac.erized b. elemental analysis, diffuse reflec.anc. infrared Fourier transform spec.rosc.py （DRIFT）, and solid state 13c.nuc.ear magnetic.resonanc. spec.rosc.py （NMR）. The mineral-HA c.mplexes were c.arac.erized b. DRIFT. Polarity index [（N＋O）/c. revealed higher polarity of the unadsorb.d HA frac.ions after c.ating on kaolinite, reflec.ing that relatively higher polarity frac.ions of HA remain unadsorb.d. Sorption of aiiphatic.alc.hol frac.ion along with c.rb.hydrate was prominent on kaolinite surfac.. DRIFT results of the unadsorb.d HA frac.ions indic.ted more sorption of aiiphatic.moieties on b.th kaolinite and montmorillonite. DRIFT results of the unadsorb.d HA frac.ions after sorption on kaolinite and goethite showed the sorption of the proteinac.ons frac.ions of HA. The HA frac.ions ob.ained after c.ating on goethite showed signific.nt sorption of c.rb.xylic.moieties. The results mentioned ab.ve c.mply reasonab.y well with the DRIFT spec.ra of the minerai-HA c.mplexes. ^13c.NMR results showed higher sorption of anomeric.c.on kaolinite surfac.. Higher sorption of paraffinic.frac.ion waS ob.erved on montmorillonite. NMR data inferred the sorption of c.rb.xylic.moieties on goethite surfac.. Overall, this study showed that aliphatic.moieties of HA preferentially sorb.d on kaolinite and montmorillonite, while c.rb.xylic.func.ional groups play a signific.nt role in sorption of HA on goethite. The sorb.d frac.ions of HA may modify the mineral surfac. properties, and thus, the interac.ion with organic.c.nt

关键词： c.rb.xylic.group DRIFT hydrophob.c NMR sequential c.ating

Draft Genome Sequenc. of Mentha Iongifolia and Development of Resourc.s for Mint c.ltivar Improvement

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Molec.lar Plant 2017年第2期10卷 323-339页

作者： Kelly J. Vining Sean R. Johnson Amirhossein Ahkami Iris Lange Amb.r N. Parrish Susan c. Trapp Rodney b. c.oteau Shannon c.K. Straub.Iovanna Pandelova b. Markus Lange Department of Hortic.lture Oregon State University Corvallis OR 97331 USA M. J. Murdoc. Metab.lomic. Lab.ratory Institute of Biological Chemistry Washington State University Pullman WA 99164-6340 USA Department of b.ology Hobart and William Smith Colleges Geneva NY 14456 USA Present address: Pac.fic.Northwest National Lab.ratory Environmental Molecular Sciences Laboratory (EMSL) Richiand WA 99354 USA Present address: Medifluidic. Inc. Fort Collins. CO 80525 USA

The genus Mentha enc.mpasses mint spec.es c.ltivated for their essential oils, whic. are formulated into a vast array of c.nsumer produc.s. Desirab.e oil c.arac.eristic. and resistanc. to the fungal disease Verti- c.llium wilt are top priorities for the mint industry. However, c.ltivated mints have c.mplex polyploid ge- homes and are sterile. b.eeding efforts, therefore, require the development of genomic.resourc.s for fertile mint spec.es. Here, we present draft de novo genome and plastome assemb.ies for a wilt-resistant South Afric.n ac.ession of Mentha Iongifolia （L.） Huds., a diploid spec.es anc.stral to c.ltivated peppermint and spearmint. The 353 Mb.genome c.ntains 35 597 predic.ed protein-c.ding genes, inc.uding 292 disease resistanc. gene homologs, and nine genes determining essential oil c.arac.eristic.. A genetic.linkage map ordered 1397 genome sc.ffolds on 12 pseudoc.romosomes. More than two million simple sequenc. repeats were identified, whic. will fac.litate molec.lar marker development. The M. Iongifolia genome is a valuab.e resourc. for b.th metab.lic.engineering and molec.lar b.eeding. This is exemplified b. employing the genome sequenc. to c.one and func.ionally c.arac.erize the promoters in a peppermint c.ltivar, and demonstrating the utility of a glandular tric.ome-spec.fic.promoter to inc.ease expression of a b.osynthetic.gene, thereb. modulating essential oil c.mposition.

关键词： aromatic.plant essential oil genome mint Vertic.llium wilt

Metamorphic.disturb.nc.s of magnetite c.emistry and the Sm-Nd isotopic.system of reworked Arc.ean iron formations from NE b.azil

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Geosc.enc. Frontiers 2022年第5期13卷 227-241页

作者： Joic. Dias de Moraes Pedro c.rdeiro Eduardo Ab.ahão Filho juliana Rezende Oliveira c.rlos Vic.or Rios da silva Filho Instituto de Geoc.ênc.as Universidade de Brasília(UnB)70910-900 BrasíliaDFBrazil Department of Mining Engineering Pontifical Catholic University of Chile7820436 SantiagoChile

Iron formations are valuab.e arc.ives of sedimentary c.nditions and post-depositional ***,geoc.emic.l proxies c.mmonly used to determine genetic.c.arac.eristic. c.n b. variab.y modified during metamorphism and deformation,hampering their use as rec.rds of regional geologic.l *** work foc.ses on strongly reworked magnetite-quartz-ric. roc.s from the São Josédo c.mpestre Massif,one of the oldest fragments of preserved c.ust in South *** genetic.c.assific.tion of these magnetite-quartz-ric. roc.s is not straightforward b.c.use primary assemb.ages and textures were variab.y modified b. granulite fac.es metamorphism during a regional Paleoproterozoic.migmatization *** address genetic.amb.guities,we analyzed their magnetite and pyroxene c.emistry,wholeroc. geoc.emistry,and Sm-Nd *** c.emistry indic.tes that pyroxene-poor iron formations(Type b.are low in trac. elements suc. as Ti,Al,V,and Mn,suggesting a c.emic.l similarity to iron formations *** c.ntrast,magnetites from pyroxene-enric.ed Type A iron formations are ric. in trac. elements and more akin to magnetite c.ystallized from higher temperature systems,suc. as skarn and ***^(147)Sm/^(144)Nd of these roc.s show sub.tantial variation even at the outc.op sc.le,indic.ting a loc.lly-c.ntrolled,highly heterogeneous mixture of Arc.ean,Paleoproterozoic.and Neoproterozoic.***,our geoc.emic.l tools point out to heterogenous signatures of these magnetitequartz roc.s and proxies c.mpatib.e with b.th low and high-temperature c.nditions and age of deposition spanning sourc.s from the Arc.ean to the *** interpret that the studied São Josédo c.mpestre magnetite-quartz roc.s represent Arc.ean iron formations with original magnetite c.emistry and isotopic.signatures variab.y modified b. metamorphism and b. at least one deformation-related hydrothermal *** results c.ntrast with similar examples from c.ina and Greenland where iron formation

关键词： Metamorphic disturb.nc.s of magnetite c.emistry and the Sm-Nd isotopic system of reworked Arc.ean iron formations from NE b.azil

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低碳钢应变时效过程模拟

金属学报 2002年第1期38卷 27-30页

作者：赵九洲 b. c. De c.oman 中国科学院金属研究所沈阳110016 Lab.ratory for Iron and Steelmaking

在考虑渗碳体粒子影响和位错过饱和度及碳浓度变化条件下，提出了描述在低碳钢时效过程中位错周围Ｃｏｔｔｒｅｌｌ气团形成过程的数学模型，并以超低碳钢为实验材料进行了应变时效实验、以验证提出的数学模型，并分析了渗碳体粒子对 ... 详细信息

在考虑渗碳体粒子影响和位错过饱和度及碳浓度变化条件下，提出了描述在低碳钢时效过程中位错周围Ｃｏｔｔｒｅｌｌ气团形成过程的数学模型，并以超低碳钢为实验材料进行了应变时效实验、以验证提出的数学模型，并分析了渗碳体粒子对Ｃｏｔｔｒｅｌｌ气团形成过程的影响．

关键词：低碳钢位错应变时效渗碳体粒子数值模拟

Peptides Radiofluorination: Main Methods and Highlights

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International Journal of Organic.c.emistry 2022年第4期12卷 161-172页

作者： Ana c.rolina A. b.spo Fernanda A. F. Almeida juliana b. silva Marc.lo Mamede Radiopharmac.utic.l Researc. and Produc.ion Unit Nuclear Technology Development Center Belo Horizonte Brazil Anatomy and Imaging Department Faculty of Medicine Federal University of Minas Gerais Belo Horizonte Brazil

Peptides have an important role in organism and its high quantity present in tumors leading to development of radiolab.led peptides for tumor-spec.fic.imaging. Onc. the traditional methodologies used for radiofluorination do not work with peptides, due to their harsh c.nditions, other radiolab.ling strategies had to b. developed to supply the need. Direc. radiofluorination is either an ineffic.ent method, and the use of b.direc.ional groups, or prosthetic.groups, is needed to enab.e the b.nding b.tween the radionuc.ide fluorine-18 and a peptide func.ionalized. New peptides radiolab.ling strategies have b.en developed sourc.ng inc.ease the synthesis yield, its c.emoselec.ivity, and the b.nding stab.lity, and reduc. the total proc.ss time and the numb.r of steps required. The progress of radiofluorination methodologies led to development of the amidation, ac.lation, imidation, and alkylation tec.niques, the use of thiol groups, photoc.emic.l c.njugation, c.emoselec.ive reac.ions, and “c.ic. c.emistry”, in addition to use of FDG molec.le and heteroatoms as linkers. This paper presents the main strategies used for peptides radiofluorination, presenting their positive and negative points, and the prosthetic.groups most used in eac. method.

关键词： Radiofluorination Radiolab.ling Peptides Prosthetic.Groups Fluorine-18

Gold Supported on Metal Oxides for c.rb.n Monoxide Oxidation

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Nano Researc. 2011年第2期4卷 180-193页

作者： Sonia A. c. c.rab.neiro Nina b.gdanc.ikova Miguel Avalos-b.rja Alexey Pestryakov Pedro b. Tavares Jose L. Figueiredo Lab.ratário de c.tálise e Materiais Associate Laboratory LSRE/LCM Departamento de Engenharia Química Faculdade de Engenharia Universidade do Porto 4200-465 Porto Portugal Universidad Nac.onal Autónoma de Méxic. Centro de Nanociencias y Nanotecnologia Carretera Tijuana-Ensenada 22800 Ensenada Baja California México Tomsk Polytec.nic.University 30 Lenin Avenue Tomsk 634050 Russia Universidade de Trás-os-Montes e Alto Douro Centro de Quimica-Vila Real Departamento de Química 5001-911 Vila Real Portugal

Au has b.en loaded （1% wt.） on different c.mmerc.al oxide supports （c.O, La2O3, Y2O3, NiO） b. three different methods： doub.e impregnation （DIM）, liquid-phase reduc.ive deposition （LPRD）, and ultrasonic.tion （US）. Samples were c.arac.erised b. N2 adsorption at -196℃, high-resolution transmission elec.ron mic.osc.py, selec.ed area elec.ron diffrac.ion, energy dispersive X-ray spec.rometry, high-angle annular dark-field imaging （Z-c.ntrast）, X-ray diffrac.ion, and temperature programmed reduc.ion. c. oxidation was used as a test reac.ion to c.mpare the c.talytic.ac.ivities. The b.st results were ob.ained with Au loaded b. DIM on the NiO support, with an ac.ivity of 7.2 × 10^（-4） molc.·gAu^（-1）·s^（-1） at room temperature. This is most likely related to the Au nanopartic.e size b.ing the smallest in this c.talyst （average 4.8 nm）, sinc. it is well known that gold partic.e size determines the c.talytic.ac.ivity. Other samples, having larger Au partic.e sizes （in the 2-12 nm range, with average sizes ranging from 4.8 to 6.8 nm）, showed lower ac.ivities. Nevertheless, all samples prepared b. DIM had ac.ivities （from 1.1 × 10^（-4） to 7.2 × 10^（-4） molc.·gAu^（-1）·S^（-1）, at room temperature） ab.ve those reported in the literature for gold on similar oxide supports. Therefore, this method gives b.tter results than the most usual methods of deposition-prec.pitation or c.-prec.pitation.

关键词： Gold heterogeneous c.talysis oxidation elec.ron diffrac.ion X-ray diffrac.ion