State University of Amapa

Macapá, Brazil

State University of Amapa

Macapá, Brazil
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Colodette J.L.,Federal University of Viçosa | Gomes C.M.,Federal University of Recôncavo da Bahia | Gomes F.J.,Federal University of Viçosa | Cabral C.P.,State University of Amapa
Applied Adhesion Science | Year: 2015

Brazil has 8.51 million km2 of territorial area and a tropical climate. In 2010, the occupation of the Brazilian soil consists of 20.8% pasture, 6.8% agriculture, 0.8% forested areas, 61.0% natural forests, and 9.7% other areas. In 2012, of the total area of the country 3.25% (27.65 million ha) is occupied by soy bean cultivation and 1% (8.5 million ha) by sugar cane cultivation. In 2012, the main cultivated species in the country were Eucalyptus spp. (71.0%), Pinus spp. (21.75%), Acacia mearnsii and Acacia mangium (2.12%), Hevea brasiliensis (2.36%), and Schizolobium amazonicum (1.22%). From 2004 to 2012, the planted forest area growth was 50.4%. The main factor that boosted this growth was the demand of the pulp and paper, followed by wood-based panels sector. It is also notable the development of new planted forests in Brazil for energy purposes. In recent decades, scientific and technological advance shave resulted in significant improvements in productivity, resistance to diseases, uniform degree of the forest plantations, wood quality etc. Among the most researched species are the ones belonging to Eucalyptus gender for having excellent adaptability to the edaphoclimatic conditions in the country. The current average productivity of Eucalyptus is of 40.7 m3/ha·year. In some regions of the country the average productivity of Eucalyptus has reached 100 m3/ha·year. The Brazilian forestry industry uses mainly planted forests, and the pulp and paper industry consumes only this type of wood. The pulp and wood panel sectors are more technologically advanced in relation to the other wood products sectors. © 2014, Colodette et al.; licensee Springer. All Right Reserved.


da Silva M.V.O.,Federal Rural University of Amazonia | Videira M.N.,State University of Amapa | Tortelly R.,Federal University of Fluminense | Clemente S.C.S.,Federal University of Fluminense | And 2 more authors.
Revista Brasileira de Parasitologia Veterinaria | Year: 2012

Aspidogastrea are globally-distributed parasites of the class Trematoda, which have been described as pathogens of a range of aquatic organisms, in marine and freshwater environments. The principal morphological characteristic of the group is an adhesive ventral disc, which is responsible for fixing the parasite to the host organism. In this study, 112 specimens of Colomesus psittacus from the municipality of Cametá, in the state of Pará (Brazil), were necropsied. Platyhelminthes of the genus Rohdella attached to the mucous membrane of the fish's intestine by the adhesive disc were observed. Fragments of parasitized tissue were fixed in Davidson solution and then processed and stained with hematoxylin-eosin. Other fragments were fixed in glutaraldehyde, processed and observed under a scanning electron microscope. The prevalence of the parasite was 76.4%, mean intensity of infection was 8.0 and mean abundance was 6.2. The parasitism provoked chronic enteritis with diffused inflammatory infiltration. The adherence of the parasite to the mucous membrane of the intestine resulted in strangulation and hyperplasia of the region, as well as causing hypertrophy of the muscle of the mucous membrane. The present study describes the anatomopathological and ultrastructural aspects of the parasitism of the intestine of C. psittacus by Rohdella sp.


Scatolino M.V.,Federal University of Lavras | Bufalino L.,State University of Amapa | Mendes L.M.,Federal University of Lavras | Tonoli G.H.D.,Federal University of Lavras
Wood Science and Technology | Year: 2017

The production of cellulose nanofibrils (CNFs) from Amazonian wood wastes could reduce pollution and raw material costs for cellulose industry. Further studies are required to analyze the feasibility of using hardwood sawdust for the production of high-quality CNF films. Therefore, the objective of this study was to evaluate the impact of various nanofibrillation degrees of waste sawdust generated from the primary processing of different hardwood species on the physical properties of CNF films. Raw sawdust was submitted to alkaline and bleaching pre-treatments. The chemical composition of the bleached fibers was determined. The CNFs were obtained by mechanical shearing of the bleached fibers using a grinder Super MassColloider after 10, 20, 30 and 40 passages. CNFs were evaluated by transmission electron microscopy. The CNF films were formed by the casting method. Residual lignin and hemicelluloses content greatly varied among species after bleaching. No clear influence of the number of passages on apparent density was observed. None of the films was degraded in significant amounts after water immersion. Water vapor absorption (WVA) consistently decreased with more passages through the Super MassColloider for Amazonian species until 30 passages. Residual hemicelluloses of the bleached fibers adversely affected WVA. Bleached fibers made of highly purified cellulose or containing residual lignin showed lower WVA after 30 and 40 passages. Water vapor permeability showed consistent relation with the apparent density of the films. For hardwood wastes, 10–30 passages through the grinder are recommended. © 2017 Springer-Verlag Berlin Heidelberg


dos Melo S.S.,Federal University of Pará | de Diniz J.E.M.,State University of Amapa | de Diniz J.E.M.,Federal University of Amapá | Guimaraes J.H.,State University of Amapa | And 7 more authors.
Chemistry Central Journal | Year: 2015

Background: The increasing efforts to reduce the environmental impact on the Amazon's natural resources are focusing on watercourses that pass through effluents with high concentrations of heavy metals. The adsorption by absorbent is one of the methods used to remove metallic ions. In this assignment, the preparation of activated carbon from Brazil nut bark (Bertholletia excelsa l.), which is a waste material produced from the use of seeds in foodstuffs and cosmetics, is shown. Results: The absorbent was carbonized at 400 °C in 3 h and activated at 800 °C in 2 h, having received the name of AC2, and, the specific area, pore size, real and apparent densities, porosity, scanning electron microscopy (SEM) coupled to energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), pH, moisture, fixed carbon and surface functional groups by Boehm method and Fourier transformed infrared spectroscopy (FTIR) were characterized. According to the results, the carbon presented alkaline characteristic, mesoporosity, average pore diameters of 2.203 nm and specific surface area by BET of 464.835 m2 g-1. The efficiency of removal was performed in synthetic solutions of copper sulphate (II) pentahydrate (CuSO4.5H2O), evaluating the influence of pH, initial concentration of copper solution (II), particle diameter and time contact of the adsorbent in solution. The results of higher removal percentages were to pH 5.09, initial concentration of 50, 100 and 150 mg-1 diameter 0.595 < D < 1.19 mm and time contact of 5 min. Conclusions: The Brazil nut bark is shown to be an important bio-waste, being an excellent alternative material for the low-cost production of activated carbon for use in processes involving iterations of adsorption. © 2015 Melo et al.


Bufalino L.,State University of Amapa | de Sena Neto A.R.,Instrumentation Unit of Brazilian Agriculture Research Corporation EMBRAPA | Tonoli G.H.D.,Federal University of Lavras | de Souza Fonseca A.,Federal University of Lavras | And 5 more authors.
Cellulose | Year: 2015

A wide range of alternative cellulose fibers for the development of new green nanomaterials can be obtained from Brazil’s natural resources. The objective of the work is to evaluate the influence of the chemical composition of hardwoods on the nanofibrillation process and optical quality of nanofiber films. Wood wastes were selected from three native Amazonian species and from exotic planted Eucalyptus grandis species. Wood sawdust was submitted to chemical alkali and bleaching pretreatments. Nanofibers were produced from the bleached fibers after 10, 20, 30 and 40 passes through a Super Mass Colloider grinder, and films were produced by the casting method. Raw sawdust, alkali-treated fibers and bleached fibers were evaluated by the major chemical components, syringyl/guaiacyl ratio, Fourier transformed infrared spectroscopy, oxygen/carbon ratio and scanning electron microscopy. Morphological characteristics of nanofibers and films were analyzed by transmission and scanning electron microscopies. Optical parameters studied for the films were the opacity, total color difference and b value. The main challenge to delignification was attributed to the low syringyl/guaiacyl ratio. The different chemical natures of Amazonian and eucalyptus hardwoods greatly affected pretreatments and, consequently, the nanofibrillation and optical quality of the films. Consequences observed for highly purified cellulose starting fibers are: (1) lower diameters for individual nanofiber elements; (2) fewer opaque and colored films produced from nanofibers; (3) a tendency to stabilization of the nanofibrillation process after 20 passes through the grinder. For species whose chemical nature hindered cellulose purification, the increased number of passes through the grinder continuously decreased the opacity. © 2015 Springer Science+Business Media Dordrecht


Melo S.S.,Federal University of Pará | Diniz J.E.M.,Federal University of Amapá | Guimaraes J.H.,State University of Amapa | Costa J.S.,Federal University of Amapá | And 6 more authors.
Chemistry Central Journal | Year: 2015

Background: The increasing efforts to reduce the environmental impact on the Amazon's natural resources are focusing on watercourses that pass through effluents with high concentrations of heavy metals. The adsorption by absorbent is one of the methods used to remove metallic ions. In this assignment, the preparation of activated carbon from Brazil nut bark (Bertholletia excelsa l.), which is a waste material produced from the use of seeds in foodstuffs and cosmetics, is shown. Results: The absorbent was carbonized at 400 °C in 3 h and activated at 800 °C in 2 h, having received the name of AC2, and, the specific area, pore size, real and apparent densities, porosity, scanning electron microscopy (SEM) coupled to energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), pH, moisture, fixed carbon and surface functional groups by Boehm method and Fourier transformed infrared spectroscopy (FTIR) were characterized. According to the results, the carbon presented alkaline characteristic, mesoporosity, average pore diameters of 2.203 nm and specific surface area by BET of 464.835 m2 g-1. Conclusions: The Brazil nut bark is shown to be an important bio-waste, being an excellent alternative material for the low-cost production of activated carbon for use in processes involving iterations of adsorption. © 2015 Melo et al.


Bufalino L.,State University of Amapa | Tonoli G.H.D.,Federal University of Lavras | Costa T.G.,Federal University of Lavras | Protasio T.D.P.,Federal University of Lavras | And 4 more authors.
Key Engineering Materials | Year: 2016

The aim of this work was to determine the best fibrillation intensity that should be used to produce high crystalline and thermal stable microfibrillated cellulose (MFC) and nanocellulose films from C. goeldiana veneer wastes. The number of passages (cycles) of cellulose suspension tested in grinder were 10, 20, 30 and 40. Important properties to be analyzed included changes in morphology from the raw wood to the nanocellulose films, increases/decreases in cellulose crystalline index for inference on biomaterial strength, and thermal behavior changes to support conclusions on biomaterials processing and application possibilities. After chemical treatments for cellulose isolation, mechanical shearing was applied to produce cellulose nanostructures; hence nanocellulose films could be successfully produced from C. goeldiana wood wastes. Influence of more refining cycles on thermal properties, indicated higher stability for 40-cycles nanocellulose films. In general, grinder refining process decreased crystalline index of cellulose. © (2016) Trans Tech Publications, Switzerland.


Vogt N.,University of Paraíba Valley | Pinedo-Vasquez M.,Columbia International University | Brondizio E.S.,Indiana University | Rabelo F.G.,State University of Amapa | And 5 more authors.
Sustainability Science | Year: 2016

The need for understanding the factors that trigger human responses to climate change has opened inquiries on the role of indigenous and local ecological knowledge (ILK) in facilitating or constraining social adaptation processes. Answers to the question of how ILK is helping or limitingsmallholders to cope with increasing disturbances to the local hydro-climatic regime remain very limited in adaptation and mitigation studies and interventions. Herein, we discuss a case study on ILK as a resource used by expert farmer-fishers (locally known as Caboclos) to cope with the increasing threats on their livelihoods and environments generated by changing flood patterns in the Amazon delta region. While expert farmer-fishers are increasingly exposed to shocks and stresses, their ILK plays a key role in mitigating impacts and in strengthening their adaptive responses that are leading to a process of incremental adaptation (PIA). We argue that ILK is the most valuable resource used by expert farmer-fishers to adapt the spatial configuration and composition of their land-/resource-use systems (agrodiversity) and their produced and managed resources (agrobiodiversity) at landscape, community and household levels. We based our findings on ILK on data recorded for over the last 30 years using detailed ethnographic methodologies and multitemporal landscape mapping. We found that the ILK of expert farmer-fishers and their “tradition of change” have facilitated the PIA to intensify a particular production system to optimize production across a broad range of flood conditions and at the same time to manage or conserve forests to produce resources and services. © 2016 Springer Japan


Neves L.R.,Aquatic Organism Health Laboratory | Braga E.C.R.,State University of Amapa | Tavares-Dias M.,Aquatic Organism Health Laboratory
Journal of Parasitic Diseases | Year: 2015

This paper is the first study on host-parasite relationship in wild Curimata incompta Vari, 1984 (Curimatidae) from Amazon river system, Northern Brazil. In 40 specimens examined from December 2012 to November 2013, 615,818 parasites were collected, such as Ichthyophthirius multifiliis, Piscinoodinium pilullare, Urocleidoides sp., Posthodiplostomum sp., Gorytocephalus elongorchis and Braga patagonica. The parasites’ component community had a low Brillouin diversity (0.16 ± 0.15), a low species richness (3.1 ± 0.7), a low evenness (0.09 ± 0.09) and a high dominance of Berger–Parker (0.96 ± 0.06). I. multifiliis was the dominant parasite species and it showed the highest prevalence and intensity in the host population. There was an aggregate dispersion of parasites, but the low parasitism did not affect the body condition of the host. The occurrence of parasites in C. incompta was due to their life habits and food behavior. This study, besides expanding the geographical distribution of G. elongorchis in Brazil, records the first occurrence of these six parasites in C. incompta. © 2015 Indian Society for Parasitology


PubMed | State University of Amapa and Aquatic Organism Health Laboratory
Type: Journal Article | Journal: Journal of parasitic diseases : official organ of the Indian Society for Parasitology | Year: 2016

This paper is the first study on host-parasite relationship in wild

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