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The Evaluation of Polyethylene/Clay Composite from Solid State NMR

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Materials Sciences and Applications 2011年第5期2卷 453-457页

作者： Regina F.Nogueira maria ines b.tavares Rosane A.S.San Gil Antonio G.Ferreira Departamento de Quimica Universidade Federal de Sao CarlosSao CarlosBrasil Laboratorio de Nanocompositos Polimericos Instituto de Macromoleculas Professora Eloisa Mano da Universidade Federal do Rio de JaneiroRio de JaneiroBrasil Departamento de Quimica Organica da Universidade Federal do Rio de JaneiroRio de JaneiroBrasil

Polymeric nanocomposites based on polyethylene (PE) and brazilian natural montmorillonite clay (MN) were obtained by melt processing, using a twin-screw extruder. The main objective of this work is focusing on the characterization of composites materials by solid-state nuclear magnetic resonance (NMR). The solid-state NMR measurements were used to observe both polymer matrix (through carbon-13 and hydrogen nuclei) and the clay (silicon-29 and aluminum-27). The polymer matrix analyses were carried out applying solid state techniques, such as: cross-polarization magic angle spinning (CPMAS), variable contact time (VCT) and by the proton spin-lattice relaxation time in the rotating frame parameter (T1ρH), detected from the resolved carbon-13 decay of the VCT experiment and through the determination of spin-lattice relaxation time, T1H (using low field NMR). The clay was analyzed by 29Si and 27Al, employing MAS NMR technique. From those techniques we can have principally response on clay dispersion in the polyethylene matrix, as well as the interactions between both components in the nanostructured material. The T1H response was an important result which showed, that the materials formed, presented different molecular domains (according to the domain size that varied from 25 to 50 nm, measured by relaxation), considering the clay dispersion mode in terms of intercalation and/or exfoliation in the polymer matrix.

关键词： NMR Polymer Polyethylene Clay Montmorillonite

Recombination-Independent Mechanisms and Pairing of Homologous Chromosomes during Meiosis in Plants

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Molecular Plant 2014年第3期7卷 492-501页

作者： Olivier Da ines maria E. Gallego Charles I. White Genetique Reproduction et Developpement UMR CNRS 6293 Clermont UniversitY INSERM U1103 63171 Aubiere France

Meiosis is the specialized eukaryotic cell division that permits the halving of ploidy necessary for game- togenesis in sexually reproducing organisms, This involves a single round of DNA replication followed by two successive divisions. To ensure balanced segregation, homologous chromosome pairs must migrate to opposite poles at the first meiotic division and this means that they must recognize and pair with each other beforehand. Although understanding of the mechanisms by which meiotic chromosomes find and pair with their homologs has greatly advanced, it remains far from being fully understood. With some notable exceptions such as male Drosophila, the recognition and physical link- age of homologs at the first meiotic division involves homologous recombination. However, in addition to this, it is clear that many organisms, including plants, have also evolved a series of recombination-independent mechanisms to facili- tate homolog recognition and pairing. These implicate chromosome structure and dynamics, telomeres, centromeres, and, most recently, small RNAs. With a particular focus on plants, we present here an overview of understanding of these early, recombination-independent events that act in the pairing of homologous chromosomes during the first meiotic division,

关键词： meiosis homolog pairing chromatin centromeres telomeres.

Nutritional,rheological and sensory properties of butter processed with different mixtures of cow and sheep milk cream

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Food bioscience 2022年第2期46卷 487-497页

作者： Renata S Dias Celso F.balthazar Rodrigo N.Cavalcanti Louise A.Sobral Jessica F.Rodrigues Roberto P.CNeto maria Inˆes b.tavares Ana Paula b.Ribeiro Renato Grimaldi Celso Sant’Anna Erick A.Esmerino Tatiana C.Pimentel Marcia Cristina Silva Adriano G.Cruz Instituto Federal de Educaç˜ao Ciˆencia e Tecnologia do Rio de Janeiro(IFRJ)Departamento de AlimentosRJBrazil Universidade Estadual de Campinas(UNICAMP) Faculdade de Engenharia de AlimentosCampinasSPBrazil Universidade Federal do Rio de Janeiro(UFRJ) Escola de QuimicaRJBrazil Instituto Federal of Minas Gerais(IFMG) Departamento de Ciˆencias Agr´ariasBambuíMGBrazil Universidade Federal do Rio de Janeiro(UFRJ) Instituto de Macromol´eculas Professora Eloisa Mano(IMA)Rio de JaneiroBrazil Instituto Federal do Paran´a(IFPR) ParanavaíPRBrazil g Instituto Nacional de MetrologiaNormalizaç˜ao Qualidade Industrial(affnInmetro) Duque de Caxias25250-020Rio de JaneiroBrazil Universidade Federal Fluminense(UFF) Faculdade de Medicina VeterinariaNiter´oiRJBrazil

This study assessed the quality parameters and consumer perception and behavior of butter processed with different ratios of cow and sheep milk *** milk cream butter(CMCb)showed lower moisture content and higher fat content,smaller fat globules,and higher concentrations of long-chain saturated fatty acids and monounsaturated fatty acids,resulting in improved potential health *** addition,CMCb showed yellow color,little salt,and butter taste as the main sensory characteristics,resulting in grateful and good digestibility *** milk cream addition improved the rheological properties of the products(lower viscosity,consistency index,and rigidity(J0),and higher fluidity and viscoelastic behavior(J1)),mainly due to the increased concentrations of short-chain and medium-chain saturated fatty acids and polyunsaturated fatty ***,sheep milk cream butter(SMCb)was characterized by a greasy and striking aroma,with a lower perception of good digestibility and good appearance,and a higher bitter *** association of cow and sheep milk cream could be an exciting option to obtain products with improved fatty acid profiles,health indices,and yet maintain desired rheological and sensory *** formulation with 60%sheep milk cream and 40%cow milk cream would be the suggested combination.

关键词： Sheep milk bovine milk Quality parameters butter

Preparation of Polycarbonate/Clay Nanocomposite and Characterization by X-Ray, Thermal Analyzes and Low-Field Nuclear Magnetic Resonance

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材料科学与工程（中英文A版） 2011年第5X期1卷 671-677页

作者： Pedro Paulo Merat maria ines bruno tavares Emerson Oliveira da Silva Instituto de Macromoleculas Professora Eloisa Mano Universidade Federal do Rio de Janeiro Centro de Tecnologia Bloco J Rio de Janeiro RJ CEP 21945-970 Brazil Instituto Federal de Educacao Ciencia e Tecnologia Rio de Janeiro Avenida Republica do ParaguaL 120 Sarapui Duque de Caxias Rio de Janeiro RJ CEP 25050-100 Brazil

ORS1, an H2O2-Responsive NAC Transcription Factor, Controls Senescence in Arabidopsis thaliana

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Molecular Plant 2011年第2期4卷 346-360页

作者： Salma balazadeh Miroslaw Kwasniewski Camila Caldana Mohammad Mehrnia maria ines Zanor Gang-Ping Xue bernd Mueller-Roeber University of Potsdam Institute of Biochemistry and Biology KarI-Liebknecht-Straβe 24-25 Haus 20 14476 Potsdam-Golm Germany Max-Planck Institute of Molecular Plant Physiology Am Muhlenberg 1 14476 Potsdam-Golm Germany University of Silesia Department of Genetics Jagiellonska 28 40-032 Katowice Poland CSIRO Plant Industry 306 Carmody Road St Lucia QLD 4067 Australia Present address: Instituto de biologia Molecular y Celular de Rosario (IbR-CONICET). Facultad de Ciencias bioquimicas y Farmaceuticas (UNR) Suipacha 530 Rosario S2002LRK Argentina

We report here that ORS1, a previously uncharacterized member of the NAC transcription factor family, controls leaf senescence in Arabidopsis thaliana. Overexpression of ORS1 accelerates senescence in transgenic plants, whereas its inhibition delays it. Genes acting downstream of ORS1 were identified by global expression analysis using transgenic plants producing dexamethasone-inducible ORSl-GR fusion protein. Of the 42 up-regulated genes, 30 （-70%） were pre- viously shown to be up-regulated during age-dependent senescence, We also observed that 32 （-76%） of the ORSl-dependent genes were induced by long-term （4 d）, but not short-term （6 h） salinity stress （150 mM NaCI）. Furthermore, expression of 16 and 24 genes, respectively, was induced after 1 and 5 h of treatment with hydrogen peroxide （H2O2）, a reactive oxygen species known to accumulate during salinity stress. ORS1 itself was found to be rapidly and strongly induced by H2O2 treatment in both leaves and roots. Using in vitro binding site selection, we determined the preferred binding motif of ORS1 and found it to be present in half of the ORSl-dependent genes. ORS1 is a paralog of ORE1/ ANACO92/AtNAC2, a previously reported regulator of leaf senescence. Phylogenetic footprinting revealed evolutionary conservation of the ORS1 and ORE1 promoter sequences in different brassicaceae species, indicating strong positive selection acting on both genes. We conclude that ORS1, similarly to ORE1, triggers expression of senescence-associated genes through a regulatory network that may involve cross-talk with saltand H2O2-dependent signaling pathways.

关键词： NAC transcription factor leaf senescence gene expression gene regulatory network hydrogen peroxide

Long noncoding RNAs:a missing link in osteoporosis

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bone Research 2019年第1期7卷 25-40页

作者： Andreia Machado Silva Sara Reis Moura JoseHenrique Teixeira Mario Adolfo barbosa Susana Gomes Santos maria ines Almeida i3S-Instituto de Investigacao e Inovacao em Sau.de University of PortoPortoPortugal INEb-Instituto de Engenharia biomedica University of PortoPortoPortugal ICbAS-Instituto de Ciências biomedicas Abel Salazar University of PortoPortoPortugal

Osteoporosis is a systemic disease that results in loss of bone density and increased fracture risk,particularly in the vertebrae and the *** condition and associated morbidity and mortality increase with population *** noncoding(lnc)RNAs are transcripts longer than 200 nucleotides that are not translated into proteins,but play important regulatory roles in transcriptional and post-transcriptional *** contribution to disease onset and development is increasingly ***,we present an integrative revision on the studies that implicate lncRNAs in osteoporosis and that support their potential use as therapeutic ***,current evidence on lncRNAs involvement in cellular and molecular mechanisms linked to osteoporosis and its major complication,fragility fractures,is *** analyze evidence of their roles in osteogenesis,osteoclastogenesis,and bone fracture healing events from human and animal model ***,the potential of lncRNAs alterations at genetic and transcriptomic level are discussed as osteoporosis risk factors and as new circulating biomarkers for ***,we conclude debating the possibilities,persisting difficulties,and future prospects of using lncRNAs in the treatment of osteoporosis.

关键词： Osteoporosis density lncRNAs

bEZIER SPLines INTERPOLATION ON STIEFEL AND GRASSMANN MANIFOLDS

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Journal of Computational Mathematics 2024年第6期42卷 1554-1578页

作者： ines Adouani Chafik Samir Department of Mathematics University of SousseTunisia LIMOS-CNRS University of Clermont AuvergneFrance

We propose a new method for smoothly interpolating a given set of data points on Grassmann and Stiefel manifolds using a generalization of the De Casteljau *** that end,we reduce interpolation problem to the classical Euclidean setting,allowing us to directly leverage the extensive toolbox of spline *** interpolated curve enjoy a number of nice properties:The solution exists and is optimal in many common *** applications,the structures with respect to chosen Riemannian metrics are detailed resulting in additional computational advantages.

关键词： Optimization b´ezier spline Curve fitting Grassmann manifolds Stiefel manifolds Canonical metrics

Diversification of SUMO-Activating Enzyme in Arabidopsis： Implications in SUMO Conjugation

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Molecular Plant 2013年第5期6卷 1646-1660页

作者： Laura Castano-Miquel Josep Segui Silvia Manrique ines Teixeira Lorenzo Carretero-Paulet Felix Atencio L. maria Lois Center for Research in Agricultural Genomics CRAG (CSIC-IRTA-UAb-Ub) Edifici CRAG-Campus UAB Bellaterra (Cerdanyola del Valles) 08193 Barcelona Spain Department of biological Sciences SUNY-University at Buffalo North Campus 109 Cooke Hall Buffalo NY 14260 USA

Sumoylation is an essential posttranslational modification that participates in many biological processes including stress responses. However, little is known about the mechanisms that control Small Ubiquitin-like MOdifier （SUMO） conjugation in vivo. We have evaluated the regulatory role of the heterodimeric E1 activating enzyme, which catalyzes the first step in SUMO conjugation. We have established that the E1 large SAE2 and small SAE1 subunits are encoded by one and three genes, respectively, in the Arabidopsis genome. The three paralogs genes SAEla, SAElbl, and SAElb2 are the result of two independent duplication events. Since SAElbl and SAElb2 correspond to two identical cop- ies, only two E1 small subunit isoforms are present in vivo： SAEla and SAElb. The E1 heterodimer nuclear localization is modulated by the C-terminal tail of the SAE2 subunit. In vitro, SUMO conjugation rate is dependent on the SAE1 isoform contained in the E1 holoenzyme and our results suggest that downstream steps to SUMO-E1 thioester bond formation are affected. In vivo, SAEla isoform deletion in T-DNA insertion mutant plants conferred sumoylation defects upon abi- otic stress, consistent with a sumoylation defective phenotype. Our results support previous data pointing to a regula- tory role of the E1 activating enzyme during SUMO conjugation and provide a novel mechanism to control sumoylation in vivo by diversification of the E1 small subunit.

关键词： E1 activating enzyme conjugation rate subcellular localization regulation abiotic stress gene duplication.

Soil properties and habitats determine the response of bacterial communities to agricultural wastewater irrigation

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Pedosphere 2020年第1期30卷 146-158页

作者： Sascha M.b.KRAUSE Anja b.DOHRMANN Osnat GILLOR bent T.CHRISTENSEN ines MERbACH Christoph C.TEbbE Thünen Institute of biodiversity Federal Research Institute for Rural AreasForestry and FisheriesBundesallee 65Braunschweig 38116Germany Zuckerberg Institute for Waster Research Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevMidreshet IL-84990Israel Department of Agroecology Aarhus UniversityAU-FolumTjele 8830Denmark Helmholtz Centre for Environmental Research-Umweltforschungszentrum(UFZ) Department Community EcologyBad Lauchstadt D-06246Germany

Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in ***,the use of secondary treated wasterwater(TWW)could have consequences for the receiving soil environment and its resident microbial *** objective of this study was to characterize the importance of soil properties and habitats to the response of soil bacteria and archaea to irrigation with *** agricultural soils with contrasting textures(loamy sand or silt loam)and,for each,three variants differing in soil organic carbon and nitrogen,as generated by long-term fertilization,were *** each of these six soils,prokaryotic communities from two habitats,i.e.,root-free bulk soil and the rhizosphere of developing cucumber plants in the greenhouse,were *** were analyzed by the quantity and diversity of their polymerase chain reaction(PCR)-amplified 16S rRNA *** account for TWW-associated nutrient effects,potable water(PW)served as a *** sequence analysis showed that prokaryotic communities mainly consisted of bacteria(99.8%).Upon irrigation,regardless of the water quality,prokaryotic diversity declined,p H increased,and no bacterial growth was detected in bulk *** contrast,the growth of cucumbers was stimulated by TWW,indicating that plants were the main ***,strong responses were seen in the rhizosphere,suggesting an indirect effect of TWW by altered *** main bacterial responders to TWW were Proteobacteria,bacteroidetes,Actinobacteria,and *** in bacterial communities due to TWW were less pronounced in all variants of the silt loam,indicating the importance of clay and soil organic carbon for buffering effects of TWW on soil bacterial ***,soil organic carbon and soil texture are important parameters that need to be considered when applying TWW in agriculture.

关键词： 16S rRNA gene sequences buffering effect cucumber rhizosphere microbial community dynamics rhizodeposition soil organic carbon soil texture treated wastewater irrigation