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Gold Nanoparticle and Berberine Entrapped into Hydrogel Matrix as Drug Delivery System

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j.urnal of Biomaterials and Nanobiotechnology 2015年第1期6卷 53-63页

作者： Camila Rufino Souza Henrique R. Oliveira Wagner M. Pinheiro Lubhandwa S. Biswaro Ricardo B. Azevedo anderson j. gomes Claure N. Lunardi Laboratory of Nanobiotechnology Faculty of Ceilandia University of Brasilia Brasilia Brazil Institute of Biological Sciences University of Brasilia Brasilia Brazil

In this study the novel hydrogel loaded with gold nanoparticle (AuNP) enhanced the berberine (BS) release when compared with other formulations of hydrogel. Hydrogels are hydrophilic polymer networks having the capacity to absorb water, ranging from about twenty to thousand times their dry weight. BS is a natural product, a quaternary ammonium salt from the group of isoquinoline alkaloids found in medicinal plants as Berberis Vulgaris. BS has some activity against dysentery, hypertension, inflammation, and liver disease in China and j.pan. In this work, BS was used as a model drug to study its association with different types of hydrogel composites of polyvinyl alcohol (BS-PVA 10%);gellan gum (BS-GG 2%), gellan gum-PVA crosslinked with cysteine (cys) (BSGG2%PVA2%cys) and gellan gum-PVA cosslinked with cysteine associated with gold nanoparticles (AuNP-BSGG2%PVA2%cys). Several parameters such as fraction of retained water (Wf), hydration percentage (%H), Swelling (DSw) and time course profile (t = 100%) (TC) were evaluated for all preparations. The results showed that the AuNP-BS-GG2%PVA2%cys was able to retain more water and swelling than the other preparations. The time course of release of the BS to the medium was greater for AuNP-BS-GG2%PVA2%cys making it a candidate to drug delivery studies in biological assays. Also Scanning Electron Microscopy (SEM) images of the surface of these hydrogel were performed. Furthermore, crosslink of the resulting hydrogels were investigated by Fourier Transform Infrared Spectroscopy (FTIR) and differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Thus, briefly, the aim of this work was to study three composition of hydrogel loaded with BS and its composition in relation to addition to AuNP and evaluate its profile for further drug delivery application using the Surface Plasmonic Resonance (SPR) as a tool improving the drug release in the new hydrogel.

关键词： Hydrogel Berberine Drug Delivery AuNPs

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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j.urnal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANDES Letícia RAMOS Dario C.PAIVA j.ssica CUNHA-BLUM Vanessa Matos gomes Daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

Digital generation of super-Gaussian perfect vortex beams via wavefront shaping with globally adaptive feedback

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High Power Laser Science and Engineering 2024年第1期12卷 42-51页

作者： Rui Ma Ke Hai Luo j.ng Song He Wei Li Zhang Dian Yuan Fan anderson S.L.gomes j.n Liu International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhenChina Institute for Advanced Study Shenzhen UniversityShenzhenChina Fiber Optics Research Centre School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina Departamento de Física Universidade Federal de PernambucoRecife-PEBrazil

High-intensity vortex beams with tunable topological charges and low coherence are highly demanded in applications such as inertial confinement fusion(ICF) and optical communication. However, traditional optical vortices featuring nonuniform intensity distributions are dramatically restricted in application scenarios that require a high-intensity vortex beam owing to their ineffective amplification resulting from the intensity-dependent nonlinear effect. Here, a low-coherence perfect vortex beam(PVB) with a topological charge as high as 140 is realized based on the super-pixel wavefront-shaping technique. More importantly, a globally adaptive feedback algorithm(GAFA) is proposed to efficiently suppress the original intensity fluctuation and achieve a flat-top PVB with dramatically reduced beam speckle contrast. The GAFA-based flat-top PVB generation method can pave the way for high-intensity vortex beam generation,which is crucial for potential applications in ICF, laser processing, optical communication and optical trapping.

关键词： digital micromirror device flat-top beam orbital angular momentum perfect vortex beam random fiber laser

Opposite latitudinal gradients for species richness and phylogenetic diversity of endemic snakes in the Atlantic Forest

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Current Zoology 2024年第4期70卷 522-530页

作者： j.séThales da Motta Portillo j.suéanderson Rēgo Azevedo Fausto Erritto Barbo Ricardo j.Sawaya Programa de Pos-Graduacao em Biologia Animal Instituto de BiocienciasLetras e Ciencias ExatasUniversidade Estadual Paulista"Julio de Mesquita Filho"Rua Cristovao Colombo2265Sao Josédo Rio PretoSao Paulo 15054-000Brazil Programa de Colecoes Cientificas Biologicas Coordenagao de BiodiversidadeInstituto Nacional de Pesquisas da AmazoniaAvenida AndréAraujo2936ManausAmazonas 69067-375Brazil Gothenburg Global Biodiversity Centre University of GothenburgBox 461GothenburgVastra Gotaland SE-40530Sweden Instituto Federal de Educacao Ciencia e Tecnologia de Minas GeraisRodovia Machado-Paraguacukm 3MachadoMinas Gerais 37750-000Rraizil Centro de Ciencias Naturais e Humanas UniversidadeFederaldo ABCRua Arcturus03Sao Bernardo do CampoSao Paulo09606-070Brazil

The decrease in species richness toward higher latitudes is an expected biogeographical *** pattern could be related to particular envi-ronmental constraints and the evolutionary history of ***,species richness does not fully represent the evolutionary history of the clades behind their *** diversity better clarifies the role of historical factors in biogeographical *** analyzed envi-ronmental and historical drivers related to latitudinal variation in species richness and phylogenetic diversity of Atlantic Forest endemic *** implemented species distribution models,from voucherbased locality points,to map the snake ranges and *** used generalized additive mixed models to evaluate the relationships among the diversity metrics and area,topographical roughness,and past climate change velocity since the Last Maximum Glacial in the Atlantic Forest latitudinal *** to the expected general pattern,species richness was higher toward higher latitudes,being positively related to past climatic *** richness also increased with total area and higher topographical *** diversity,on the other hand,showed opposite relationships related to the same *** diversity increased with lower climatic stability in lower ***,dimensions of diversity were affected in different ways by historical and environmental constraints in this unique and threatened biodiversity hotspot.

关键词： biodiversity latitudinal gradient neotropical region phylogenetic diversity serpents species richness.

Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial

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Stroke & Vascular Neurology 2024年第1期9卷 38-49,I0035-I0046页

作者： j.son Philip Appleton Lisa j.Woodhouse Craig S anderson Sandeep Ankolekar Lesley Cala Mark Dixon Timothy j.England Kailash Krishnan Grant Mair Keith W Muir j.hn Potter Christopher I Price Marc Randall Thompson G Robinson Christine Roffe Else C Sandset j.ffrey L Saver Angela Shone Aloysius Niroshan Siriwardena j.anna M Wardlaw Nikola Sprigg Philip M Bath Stroke University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Applied HealthResearch University of Birmingham College of Medical and Dental SciencesBirminghamUK Stroke Trials Unit Mental Health and Clinical NeurosciencesUniversity of NottinghamNottinghamUK Faculty of Medicine The George Institute for Global HealthSydneyNew South WalesAustralia The George Institute China at Peking University Health Science Center BeijingChina Neurology Royal Prince Alfred HospitalSydney Health PartnersSydneyNew South WalesAustralia Department of Neurology King's College Hospital NHS Foundation TrustLondonUK Faculty of Health and Medical Sciences University of Western AustraliaCrawleyWestern AustraliaAustralia East Midlands Ambulance Service NHS Trust NottinghamUK Stroke Queen's Medical CentreNottingham University Hospitals NHS TrustNottinghamUK Centre for Clinical Brain Sciences Dementia Research InstituteUniveristy of EdinburghEdinburghUK Institute of Neurology and Psychology University of GlasgowGlasgowUK Bob Champion Research and Education Building University of East AngliaNorwichUK Institute of Neuroscience Newcastle UniversityNewcastle upon TyneUK Department of Neurology Leeds Teaching Hospitals NHS TrustLeedsUK Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre University of LeicesterLeicesterUK Stroke Research in Stoke Institute for Science and Technology in MedicineKeele UniversityStoke-on TrentUK Department of Neurology Oslo University HospitalOsloNorway Research and Development Norwegian Air Ambulance FoundationOsloNorway Department of Neurology and Comprehensive Stroke Center David Geffen School of MedicineUCLALos AngelesCaliforniaUSA Research and Graduate Services University of NottinghamNottinghamUK Community and Health Research Unit University of LincolnLincolnUK

Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is ***,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of *** primary outcome was a shift in scores on the modified Rankin scale(mRS)at day *** outcomes included death;a global analysis(Wei-Lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’*** were reported as n(%),mean(SD),median[IQR],adj.sted common OR(acOR),mean difference or Mann-Whitney difference(MWD)with 95%*** 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow Coma Scale 14(2)and time from onset to randomisation 67[45,108]***‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%CI 0.85 to 1.54),death or global analysis(MWD 0.00,95%CI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe *** In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital *** IS ALREADY KNOWN ON THIS TOPIC⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those w

关键词： Glasgow nitrate random

Broadband Optical Active Waveguides Written by Femtosecond Laser Pulses in Lithium Fluoride

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Chinese Physics Letters 2014年第1期31卷 72-75页

作者： Ismael Chiamenti Francesca Bonfigli anderson S. L. gomes Rosa Maria Montereali Larissa N. da Costa Hypolito j. Kalinowski Federal University of Technology- Parang 80230-901 Curitiba Brazil ENEA C. R. Frascati Photonics Micro and Nanostructures Laboratory UTAPRAD-MNF V. E. Fermi 45 00044 Frascati (Rome) Italy Department of Physics Universidade Federai de Pernambuco necife Brazil

Broadband waveguiding through light-emitting strips directly written in a blank lithium fluoride crystal with a femtosecond laser is reported. Light guiding was observed at several optical wavelengths, from blue, 458 nm, to near-infrared, at 155nm. Visible photoluminescence spectra of the optically active F2 and F33 color centers produced by the fs laser writing process were measured. The wavelength-dependent refractive index increase was estimated to be in the order of 10-3-10-4 in the visible and near-infrared spectral intervals, which is consistent with the stable formation of point defects in LiF.

关键词： POINT defects CRYSTAL defects IMPURITY centers ANTISITE defects INTERSTITIALS FLUX pinning

ecent advances in selective acetylene hydrogenation using palladium containing catalysts

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Frontiers of Chemical Science and Engineering 2015年第2期9卷 142-153页

作者： Alan j. McCue j.mes A. anderson Surface Chemistry and Catalysis Group Department of Chemistry University of Aberdeen Aberdeen AB24 3UE UK Materials and Chemical Engineering Group School of Engineering University of Aberdeen Aberdeen AB24 3UE UK

Recent advances with Pd containing catalysts for the selective hydrogenation of acetylene are described. The overview classifies enhancement of catalytic proper- ties for monometallic and bimetallic Pd catalysts. Activity/ selectivity of Pd catalysts can be modified by controllingparticle shape/morphology or immobilisation on a support which interacts strongly with Pd particles. In both cases enhanced ethylene selectivity is generally associated with modifying ethylene adsorption strength and/or changes to hydride formation. Inorganic and organic selectivity modifiers （i.e., species adsorbed onto Pd particle surface） have also been shown to enhance ethylene selectivity. Inorganic modifiers such as TiO2 change Pd ensemble size and modify ethylene adsorption strength whereas organic modifiers such as diphenylsulfide are thought to create a surface template effect which favours acetylene adsorption with respect to ethylene. A number of metals and synthetic approaches have been explored to prepare Pd bimetallic catalysts. Examples where enhanced selectivity is observed are generally associated with decreased Pd ensemble size and/or hindering of the ease with which an unselective hydride phase is formed for Pd. A final class of bimetallic catalysts are discussed where Pd is not thought to be the primary reaction site but merely acts as a site where hydrogen dissociation and spillover occurs onto a second metal （Cu or Au） where the reaction takes place more selectively.

关键词： acetylene ethylene selective hydrogenation,palladium bimetallic

Release, Recycle, Rebuild： Cell-Wall Remodeling, Autodegradation, and Sugar Salvage for New Wall Biosynthesis during Plant Development

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Molecular Plant 2018年第1期11卷 31-46页

作者： William j. Barnes Charles T. anderson Department of Biology Center for Ugnocellulose Structure and Formation The Pennsylvania State University University Park PA 16802 USA

Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precur- sors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evi- dence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the develop- mental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.

关键词： Plant cell walls wall degradation wall recycling wall biosynthesis

Adding Value to Crop Production Systems by Integrating Forage Cover Crop Grazing

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American j.urnal of Plant Sciences 2024年第3期15卷 180-192页

作者： Robert B. Mitchell Daren D. Redfearn Kenneth P. Vogel Terry j. Klopfenstein Galen Erickson P. Stephen Baenziger Bruce E. anderson Mary E. Drewnoski j.y Parsons Steven D. Masterson Marty R. Schmer Virginia L. j.n USDA-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA Department of Animal Science University of Nebraska-Lincoln Lincoln NE USA Department of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USDA-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In addition to their value as cereal grains, wheat (Triticum aestivum L.) and triticale (× Triticosecale Wittmack) are important cool-season annual forages and cover crops. Yearling steer (Bos taurus) performance was compared in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated pastures (0.4 ha) were no-till seeded in three consecutive years into soybean stubble in autumn, fertilized, and grazed the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked in spring with four yearling steers (380 ± 38 kg) for 17, 32, and 28 d in 2005, 2006, and 2007, respectively. In 2005, average daily gain (ADG) for steers grazing triticale exceeded the ADG for wheat by 0.31 kghd-1d-1. In 2006, wheat ADG exceeded that for triticale by 0.12 kghd-1d-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained 0.20 kghd-1d-1. Based on the 3-year average animal gains valued at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and $22.55 for wheat. Since these grazed cover crops provide ecosystem services in addition to forage, grazing could be viewed as a mechanism for recovering costs and adds additional value to the system. Based on this 3-year grazing trial, triticale was superior to wheat and likely will provide the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat