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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

The nanocomposites based on polycarbonate and organophilic montmorillonite were prepared by solvent cast method, using different ratios of organophilic montmorillonite. The intermolecular interactions and molecular dynamics of the nanocomposites obtained have been evaluated by spin-lattice relaxation time determined by nuclear magnetic resonance. They have also been characterized by X-ray diffraction to confirm the changes in the organoclay structure after being incorporated in the polymeric matrix. The thermal stability of both polymer and nanocomposites were also studied by thermogravimetric analysis. The glass transition temperature was determined by differential scanning calorimetry. The sum of all results indicates that nanocomposites obtained presented a predominant intercalated morphology.

关键词：纳米复合材料 X射线衍射分析低场核磁共振聚碳酸酯热分析制备差示扫描量热法玻璃化转变温度

Clinical and pathological characterization of epstein-barr virus-associated gastric carcinomas in portugal

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World Journal of Gastroenterology 2017年第40期23卷 7292-7302页

作者： Joana Ribeiro Andreia Oliveira Mariana Malta Claudia Oliveira Fernanda silva Ana Galaghar Luís pedro Afonso Maria Cassiano Neves Rui Medeiros pedro Pimentel-Nunes Hugo Sousa Molecular Oncology and Viral Pathology Group Portuguese Oncology Institute of Porto Faculty of Medicine of Porto University Department of Pathology Portuguese Oncology Institute of Porto Medical Oncology Department Portuguese Oncology Institute of Porto Instituto CUF de Oncologia Virology Service Portuguese Oncology Institute of Porto Research Department-Portuguese League Against Cancer(Liga Portuguesa Contra o Cancro-Núcleo Regional do Norte) Gastroenterology Service Portuguese Oncology Institute of Porto CINTESIS-Center for Health Technology and Services Research(Centro de Investigacao Médica Faculdade de Medicina da Universidade do Porto)

AIM To determine the prevalence of epstein-barr virus(eb V)-associated gastric carcinomas in the North Region of Portugal and to study its clinicopathological characteristics. METHODS We have performed a retrospective study including a total of 179 consecutive patients with gastric cancer(GC) submitted to gastrectomy during 2011 at the Portuguese Oncology Institute of Porto. Clinical and pathological data was collected from individual clinical records and inserted on a database with unique codification. Tumour tissues were collected from the institutional tumour bank. eb V was detected by in situ hybridization for the detection of eb V-encoded small RNAs(ebe Rs) and eb V latent proteins(LMP1 and LMP2 A) were detected by *** The analysis showed that eb V-associated gastric carcinomas(eb Va GC) represents 8.4%(15/179) of all GC cases, with a significant differential distribution among histological types(P < 0.001): 100%(3/3) of medullary carcinomas, 100%(1/1) of adenosquamous carcinoma, 8.7%(8/92) of tubular adenocarcinomas, 8.0%(2/25) of mixed carcinomas and 2%(1/51) in poorly cohesive carcinomas. The analysis revealed a higher predominance of eb Va GC in the upper third and middle(cardia, fundus and body) of the stomach(P = 0.041), a significant lower number of regional lymph nodes invasion(P = 0.025) and a tendency for better prognosis(P = 0.222). eb V latent protein expression revealed that all eb Va GC cases were LMP1-negative, nevertheless 6 cases(40%) expressed LPM2 A, which reveals that these cases show a distinct eb V-Latency profile(latency II-like).CONCLUSION eb Va GC represents 8.4% of all GC in the North Region of Portugal. The eb V-infected patients have specific clinic-pathological features that should be further explored to develop new strategies of management and treatment.

关键词： Gastric cancer Epstein-barr virus Prevalencel Epstein-barr virus-associated gastric carcinomas

Enzyme from Banana(Musa sp.)Extraction Procedures for Sensitive Adrenaline Biosensor Construction

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American Journal of Analytical Chemistry 2013年第6期4卷 293-300页

作者： Solange Carvalho da silva Célio Wisniewski pedro Orival Luccas Cristiana Schmidt de Magalhaes Exact Sciences Institute Federal University of Alfenas—Unifal-MGAlfenasBrazil Chemistry Institute Federal University of Alfenas—Unifal-MGAlfenasBrazil

For building a biosensor, at least two enzyme sources can be employed. The pure enzyme has features with better selectivity and low stability. Crude extract presents better stability and wrong selectivity. Thus, one intermediate condition can be feasible joining both benefits of crude extract and pure enzymes. For that result, several procedures of extraction and semi purification of polyphenol oxidase (PPO) enzyme from banana (Musa sp.) were studied. The results showed that cleaned enzymatic extracts presented higher specific activities than crude extracts (2.8 up to 5.3 fold), despite the total protein concentration diminishing from 27% up to 72%, indicating that polyphenol oxidase (PPO) enzyme was preserved in them. The biosensors with 125 AU mL-1 containing cleaned enzymatic extracts performed better by grinding or grinding plus sonication for 30 s. They were linear over the ranges of 5.9 × 10-6 mol·L-1 to 1.4 × 10-3 mol·L-1 and 7.9 × 10-8 mol·L-1 to 4.0 × 10-3 mol·L-1, respectively. The limit of Detection (LOD) was 5.9 × 10-6 mol·L-1 and 7.9 × 10-8 mol·L-1, respectively. The LOD obtained is adequate to adrenaline determination on blood and medicinal samples, and were applied in medicinal samples with satisfactory results.

关键词： Enzymatic Extract Epinephrine Biosensor Polyphenol Oxidase

Histological analysis and transcription profiles on somatic embryogenesis in interspecific hybrids of <i>Elaeis guineensis ×E. oleifera</i>

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Agricultural Sciences 2013年第11期4卷 1-11页

作者： Paula Cristina da silva Angelo Douglas André Steinmacher Ricardo Lopes Raimundo Nonato Vieira da Cunha Miguel pedro Guerra Embrapa Western Amazon Manaus Brazil UFSC Federal University of Santa Catarina—CCA Graduate Program in Plant Genetic Resources Physiology of Development and Plant Genetics Laboratory Florianópolis Brazil Brazilian Council for Technological Development—CNPq Brazil

Elaeis guineensis (African oil palm) and E. oleifera (American oil palm) are bred to attain high oil yields, disease resistances, and decelerated shoot elongation. We cultivated immature zygotic embryos from backcrossed and F1 interspecific progenies on media containing 110, 150, or 200 mg·l-1 2,4-diclorophenoxyacetic acid (2,4-D) to obtain embryogenic cultures. These were set to multiply on medium containing 8 mg·l-1 2,4-D or lower concentrations of auxins and finally we induced plantlets regeneration, from each zygotic embryo, independently, in order to have the clones organized according to their respective origins. Reductions in auxins induced cultures to revert from highly embryogenic into competent for embryogenesis and finally to organogenic degenerated callus lines. Histology and the expression of SOMATIC EMBRYOGENESIS RECEPTOR KINASE, DEHYDRIN, DEFENSIN, TRANSPOSASE, and LIPID TRANSFER PROTEIN were analyzed on four callus lines representative of morphological aspects consistently observed. The highest number of embryogenic cultures was obtained on 150 mg·l-1 2,4-D. Maturation and multiplication of somatic embryos through secondary embryogenesis occurred simultaneously on 8 mg·l-1 2,4-D. LIPID TRANSFER PROTEIN expression was detected in one of the embryogenic cultures and correlated with protoderm onset. Three six-week cycles on induction medium yielded 1.5 shoots above 6 cm per poly-embryogenic complex, which performed better than embryoids individualized mechanically. Rooting was observed for 77% and 82% of shoots from these two types of explants, respectively. Rooted plantlets ready for acclimatization were obtained nine months after shoot

关键词： Amazon Arecaceae Dendê Caiaué Gene Expression

Numerical Implementation and Calibration of a Hysteretic Model for Cyclic Response of End-Plate Beam-to-Column Steel Joints under Arbitrary Cyclic Loading

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Numerical Implementation and Calibration of a Hysteretic Mod...

Formulations Containing Curcumin or Trans-Resveratrol Increase Dermal Thickness in Rats Submitted to Chemical Peeling

The 10th EPMESC

作者： pedro Nogueiro Luís Sim■es da silva Rita Bento Polytechnic Institute of Bragana Bragana Portugal Department of Civil Engineering University of Coimbra - Polo II Pinhal de Marrocos Coimbra Portugal Department of Civil Engineering Instituto Superior Técnico Av. Rovisco Pais Lisbon Portugal

This work presents the implementation and calibration of Modified Richard-Abbott model for cyclic response of four end-plate beam-to-column steel joints under arbitrary cyclic loading. The joints para

关键词： Implementation Calibration Hysteretic model Hysteretic energy dissipation Steel Joint.

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Journal of Cosmetics, Dermatological Sciences and Applications 2017年第1期7卷 14-26页

作者： Gisele Mara silva Gonç alves pedro Paulo Barros Gustavo Henrique da silva Erica Mendes dos Santos Amanda Figlia Minutti Faculty of Pharmaceutical Sciences Pontifical Catholic University of Campinas Campinas Brazil

Plant-derived substances such as curcumin and trans-resveratrol, both of which have anti-inflammatory properties, may have a beneficial effect on human skin. The present study analyzed the effects of topical formulations containing curcumin or trans-resveratrol on the recovery and rejuvenation of skin after chemical peeling. The study was performed on rats, randomly divided into seven groups of six animals each. Superficial peeling was performed using a 50% glycolic acid gel, which was applied to the dorsal region of each animal. Rats were then treated with the experimental formulations for 15 days. On the sixteenth day, skin samples were taken and mounted on slides for histological analysis. Statistical analysis showed that the formulation containing trans-resveratrol led to increased dermal and epidermal thickness, while the formulation containing curcumin had no effects on epidermal thickness. The increased epidermal thickness may reflect greater skin vitality, although this was not directly evaluated. The increase in dermal thickness may be attributed to greater collagen production, which may increase skin firmness and elasticity, and lead to skin rejuvenation as well as wrinkle reduction. Formulations containing curcumin or trans-resveratrol may have potential for the topical treatment after peeling and of sensitive skin, in addition to being used for their antiaging properties.

关键词： Curcumin Resveratrol Peeling Histological Analysis

Towards the Recovery of By-Product Metals from Mine Wastes:An X-Ray Absorption Spectroscopy Study on the Binding State of Rhenium in Debris from a Centennial Iberian Pyrite Belt Mine

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Journal of Minerals and Materials Characterization and Engineering 2014年第2期2卷 135-143页

作者： Maria-Ondina Figueiredo Teresa Pereira da silva Joao pedro Veiga daniel de Oliveira Maria Joao Batista CENIMAT/I3N Faculty of Sciences and TechnologyNew University of LisbonCampus da CaparicaLisbonPortugal Unit of Mineral Resources and Geophysics National Laboratory for Energy and GeologyAmadoraPortugal

Rhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on ex- ploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of Sao Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.

关键词： Mine Waste Materials By-Products Iberian Pyrite Belt Rhenium XANES Re L_(3)-Edge

Evapotranspiration and water-use efficiency of irrigated colored cotton cultivar in semiarid regions

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Agricultural Sciences 2012年第5期3卷 714-722页

作者： pedro V.de Azevedo José R.C.Bezerra Vicente de P.R.da silva Federal University of Campina Grande Campina GrandeBrazil Brazilian Company for Agriculture and Animal Research(Embrapa Algodão) Campina GrandeBrazil

Irrigation studies provide a framework for evaluating agricultural production and the water resource management in locations where water is scarce. Field experiments were conducted at Barbalha- CE (northwestern Brazil) during 2004 and 2005 cropping seasons to investigate the effects of different irrigation water depths on the water-use efficiency and yield of the BRS 200-brown cotton cultivar (Gossypium hirsutum L.). Three irrigation treatments were applied: T1 = 80%;T2 = 100% and T3 = 120% of the potential evapotranspiration (ETp). The Bowen ratio-energy balance was used to obtain crop evapotrnaspiration (ETc) while daily reference evapo-transpiration (ETo) was obtained by the Penman-Monteith approach. Irrigation water was applied by a sprinkler system during both cropping seasons. The daily evapotranspiration ranged from 2.59 mm·day-1 at the emergence to 5.89 mm·day-1 at first square growth stage with an accumulated value of 528.7 mm as a mean of the two cropping seasons. The average crop coefficient across both years (2004-2005) was 0.90, with minimum and maximum values of 0.46 and 1.17 at emergency and first flower growth stages, respectively. The results also showed that the increase in irrigation from 80% to 120% of ETp resulted in a significant increase in the seed-cotton yield (from 2476.0 to 3289.5 kg·ha-1), while lint percentage and water-use efficiency (WUE) were slightly reduced from 35.7% to 35.6% and from 0.60 to 0.53 kg·m-3, respectively. These results suggests that the cotton crop (cultivar BRS-200 brown) reaches higher water-use efficiency when irrigated with 80% of the crop evapotrnaspiration obtained as a function of the reference evapotranspiration and the crop coefficient proposed by FAO. However, the maximum seed-cotton yield is obtained when irrigated with 120% of that crop evapotranspiration.

关键词： Bowen Ratio Crop Evapotranspiration Irrigation Treatments Seed-Cotton Yield

Phenology and Vegetative Growth in a New Production Region of Grapevines:Case Study in Sao Joaquim,Santa Catarina,Southern Brazil

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Open Journal of Ecology 2014年第6期4卷 321-335页

作者： Marcelo Borghezan Larissa Villar Tatiane Carine da silva Monica Canton Miguel pedro Guerra Claudia Guimaraes Camargo Campos UFSC—Universidade Federal de Santa Catarina FlorianopolisBrazil UDESC—Universidade do Estado de Santa Catarina LagesBrazil

In Brazil winemaking is expanding not only in the renewal of vineyards in traditional production areas, but also in the introduction of new crops in the newer winemaking regions. Promising characteristics were observed in the quality of the grapes and wines produced in altitude regions of Santa Catarina. The aim of this study is to characterize the geographic and climatic conditions which affect the phenology and vegetative growth of grapevine in S?o Joaquim, in the mountains region of Santa Catarina. The vineyards are located in areas with undulated and strongly undulated relief, predominantly in soils originating from basaltic rocks, in climate conditions classified as Cfb according to the K?ppen, as Region I according to Winkler classification. The phenological stage of the grapevines in the S?o Joaquim region begins later and lasts longer in comparison to other winegrowing regions in Brazil. Decrease in photoperiod and low temperatures (<10?C) were the determining factors for the induction of growth cessation of the shoots in S?o Joaquim. The geographic location in a lower latitude and its high altitude results in a distinct growing climate compared to the other winegrowing regions in Brazil.

关键词： Vitis vinifera L. Climate Characterization Phenological Events Ecophysiology

Kinetics and thermodynamic studies of Methyl Orange removal by polyvinylidene fluoride-PEDOT mats

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Journal of Environmental Sciences 2021年第2期33卷 62-73页

作者： Romario J.da silva Lizeth Carolina Mojica-Sanchez Filipe D.S.Gorza Graciela C.pedro Bruna G.Maciel Gabriela P.Ratkovski Herica D.daRocha Kamila T.O.do Nascimento Juan CMedina-Llamas Alicia E.Chavez-Guajardo Jose J.Alcaraz-Espinoza Celso P.de Melo Program a de Pos-Graduagao em Ciencia de Materials U niversidade Federal de Pernambuco50670-901 RecifePEBrazil Departamento de Ffsica Uniuersidade Federal de Pemambiico50670-901 Reci/ePEBrazil Centro de Estudios Cientificosy Tecnologicos No.18 Instituto Politecnico Nacional98160 ZacatecasZacMexico Unidad Academica de Ciencias de la Tierra Uniuersidad Aut6noma de Zacatecas98058 ZacatecasZacMexico Departamento de Quimica Universidad Autonoma Metropolitana09340Ciudad de MexicoMexico

We report the preparation of poly(3,4-ethylene dioxythiophene)(PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange(MO)from aqueous *** novel adsorbent material can be used to selectively remove MO on a wide p H range(3.0-10.0),with a maximum capacity of 143.8 mg/g at p H *** used in a recirculating filtration system,the maximum absorption capacity was reached in a shorter time(20 min)than that observed for batch mode experiments(360 min).Based on the analyses of the kinetics and adsorption isotherm data,one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is ***,considering the estimated values for the Gibbs energy,and entropy and enthalpy changes,it was established that the adsorption process is spontaneous and occurs in an endothermic *** good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles,without significant loss of their *** suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.

关键词： Electrospinning Composite mats Pedot Pvdf mats Dye removal Water remediation