Bone defect healing is often compromised by infections acquired during surgery, hindering regeneration. An effective solution should first prevent infection and then promote bone repair. Localised drug-delivery systems capable of dual and sequential release of antimicrobial and bone-regenerative agents represent a promising solution; however, precisely controlling this sequential release remains an unmet challenge.
View Article and Find Full Text PDFPlants cope with the environment by displaying large phenotypic variation. Two spectra of global plant form and function have been identified: a size spectrum from small to tall species with increasing stem tissue density, leaf size, and seed mass; a leaf economics spectrum reflecting slow to fast returns on investments in leaf nutrients and carbon. When species assemble to communities it is assumed that these spectra are filtered by the environment to produce community level functional composition.
View Article and Find Full Text PDFBauxite mining has been caused severe changes in the natural ecosystems of the Amazon, but the restoration of these areas is mandatory by federal law in Brazil. The recolonization of fauna is crucial to establishing the ecological functions of recovering forests, and the small nonflying mammals can stand out in this process. Assessing taxonomic and functional diversity parameters, we demonstrated that in the early stages of forest recovery post-bauxite mining, between 6 and 11 years, it is possible to restore approximately 45% of the richness of small non-flying mammal species from the original habitats, that in this case were altered Primary Forests.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Unlike most rivers globally, nearly all lowland Amazonian rivers have unregulated flow, supporting seasonally flooded floodplain forests. Floodplain forests harbor a unique tree species assemblage adapted to flooding and specialized fauna, including fruit-eating fish that migrate seasonally into floodplains, favoring expansive floodplain areas. Frugivorous fish are forest-dependent fauna critical to forest regeneration via seed dispersal and support commercial and artisanal fisheries.
View Article and Find Full Text PDFCommun Biol
October 2024
We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Within-plot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions.
View Article and Find Full Text PDFTrees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge.
View Article and Find Full Text PDFUsing 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness.
View Article and Find Full Text PDFIn a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies.
View Article and Find Full Text PDFThis study aimed to compare the efficacy of XP-endo Finisher R and IrriSafe, with a solvent mixture of Methyl ethyl ketone/Tetrachloroethylene (MEK/TCE), in the removal of root filling residues. Twenty-four human mandibular incisors were pair-matched by micro-computed tomography according to volume and aspect ratio. After retreatment, specimens were allocated to two experimental groups (n = 12), according to the supplementary instrument used.
View Article and Find Full Text PDFThe aim of this study was to compare the effects of new irrigation solvent mixtures with Methyl ethyl ketone (MEK)/Tetrachloroethylene (TCE) and MEK/Orange oil (OOil), and different agitation techniques on dentin hardness. One hundred forty-four mandibular teeth were prepared and standardized, with each root's middle part transversely sectioned. Initial hardness was measured using a Vickers microhardness tester.
View Article and Find Full Text PDFMaterials (Basel)
July 2020
Objectives: This study reports the efficacy of two solvent mixtures on the dissolution of gutta-percha and AH Plus sealer, together with the cytotoxicity.
Methods: Methyl ethyl ketone (MEK), orange oil, tetrachloroethylene, MEK/tetrachloroethylene (1:1), MEK/orange oil (1:1), and chloroform (control) were tested. Twelve groups ( = 15) of standardized stainless-steel molds filled with softened gutta-percha cones and twelve ( = 15) filled with AH Plus were immersed in the corresponding mixture or individual solvent, in an ultrasonic bath, for either 2 or 5 min.
Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals, where aggregation increases with rarity.
View Article and Find Full Text PDFSci Rep
September 2019
Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions.
View Article and Find Full Text PDFJ Biomed Mater Res A
October 2019
Currently available scaffolds for tissue repair have shown very limited success, so many efforts have being put in the development of novel functional materials capable of regulating cell behavior and enhance the tissue healing rate. Piezoelectric materials, as zinc oxide (ZnO), can be a very interesting solution for scaffold development, as they can deliver electrical signals to cells upon mechanical solicitation, allowing the development of suitable microenvironments for tissue repair. This way, it is reported the deposition of ZnO thin films on a polymer by direct current magnetron sputtering, under different conditions, in order to obtain a piezoelectric ZnO thin film with potential for tissue repair applications.
View Article and Find Full Text PDFThe dominance structure of primate social groups varies widely. In addition to the groups' composition, intrinsic attributes such as sex, body size and life experience are important factors that can affect hierarchical dominance relations. All primates are social animals, and the social environment has a direct influence on the physiological conditions of vital systems such as immunological, reproductive and cardiovascular systems.
View Article and Find Full Text PDFWe determined the filtered tree species pool of Amazonian wetland forests, based on confirmed occurrence records, to better understand how tree diversity in wetland environments compares to tree diversity in the entire Amazon region. The tree species pool was determined using data from two main sources: 1) a compilation of published tree species lists plus one unpublished list of our own, derived from tree plot inventories and floristic surveys; 2) queries on botanical collections that include Amazonian flora, curated by herbaria and available through the SpeciesLink digital biodiversity database. We applied taxonomic name resolution and determined sample-based species accumulation curves for both datasets, to estimate sampling effort and predict the expected species richness using Chao's analytical estimators.
View Article and Find Full Text PDFAutograft has been carried out for anterior cruciate ligament (ACL) reconstruction surgery. However, it has negative aspect because patients lose their healthy ligaments from other part. We focus on a chitosan-hydroxyapatite (HAp) composite fiber as a scaffold of ligament regeneration.
View Article and Find Full Text PDFJ Endod
September 2017
Introduction: The purpose of this study was to evaluate the use of solvents that are not traditionally used in dentistry for the dissolution of an epoxy resin-based sealer and the effect of ultrasonic agitation (UA).
Methods: The dissolution of the AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) and the effect of UA in various solvents (eucalyptol, xylene, chloroform, EndoSolv R [Septodont, Cedex, France], EndoSolv E [Septodont], methyl ethyl ketone [MEK], and ethyl acetate) were quantified. The dissolving capacity was assessed by weight loss, Vicker microhardness, scanning electron microscopy (SEM), and X-ray diffraction (XRD).
Int J Pharm
May 2017
The functional and structural performance of a 5cm synthetic small diameter vascular graft (SDVG) produced by the copolymerization of polyvinyl alcohol hydrogel with low molecular weight dextran (PVA/Dx graft) associated to mesenchymal stem cells (MSCs)-based therapies and anticoagulant treatment with heparin, clopidogrel and warfarin was tested using the ovine model during the healing period of 24 weeks. The results were compared to the ones obtained with standard expanded polyetetrafluoroethylene grafts (ePTFE graft). Blood flow, vessel and graft diameter measurements, graft appearance and patency rate (PR), thrombus, stenosis and collateral vessel formation were evaluated by B-mode ultrasound, audio and color flow Doppler.
View Article and Find Full Text PDFInt J Pharm
November 2016
The functional and structural performance of a 5cm synthetic small diameter vascular graft (SDVG) produced by the copolymerization of polyvinyl alcohol hydrogel with low molecular weight dextran (PVA/Dx graft) associated to mesenchymal stem cells (MSCs)-based therapies and anticoagulant treatment with heparin, clopidogrel and warfarin was tested using the ovine model during the healing period of 24 weeks. The results were compared to the ones obtained with standard expanded polyetetrafluoroethylene grafts (ePTFE graft). Blood flow, vessel and graft diameter measurements, graft appearance and patency rate (PR), thrombus, stenosis and collateral vessel formation were evaluated by B-mode ultrasound, audio and color flow Doppler.
View Article and Find Full Text PDFThe large surface area and ability to retain moisture of textile structures enable microorganisms' growth, which causes a range of undesirable effects, not only on the textile itself, but also on the user. Due to the public health awareness of the pathogenic effects on personal hygiene and associated health risks, over the last few years, intensive research has been promoted in order to minimize microbes' growth on textiles. Therefore, to impart an antimicrobial ability to textiles, different approaches have been studied, being mainly divided into the inclusion of antimicrobial agents in the textile polymeric fibers or their grafting onto the polymer surface.
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