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1.
Foods ; 13(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38890848

RESUMO

The objective of this research was to investigate and compare the results obtained in the intensification and integration of (sc-CO2) under different pressure conditions (25 and 30 MPa) at 60 °C. When intensifying the process, ethanol (10%) was used as a co-solvent (sc-CO2 + EtOH). In the process integration, black soldier fly larvae flour, defatted via supercritical extraction (SFE), was the raw material for pressurized liquid extraction (PLE) using ethanol as solvent. The extract yields, fatty acid profile, free fatty acids, triacylglycerols (TAGs), oxidative stability, and nutritional quality of the oil obtained using sc-CO2 + EtOH were evaluated. The composition of bioactive compounds (carotenoids, acidity, antioxidant compounds, tocopherols, and phospholipids) was determined in both extracts. The yields of the extracts were different by 32.5 to 53.9%. In the extracts obtained with sc-CO2 + EtOH (10%), the predominant fatty acids were oleic, palmitic, and linoleic, with considerable levels of desirable fatty acids (DFA), tocopherols, and phospholipids. The nutritional indices showed good values for polyunsaturated and saturated fatty acids (PUFAs/SFAs), above 0.45%. Extracts from larvae meal defatted with SFE showed carotenoids, phenolic compounds, and antioxidant activity. HPTLC and HPLC analyses indicated the presence of amino acids, sugars, phenolics, and organic acids in their composition. This study revealed that the supercritical fluid extraction (SFE) process, or its conditions, can modify the fatty acid composition and the presence of minor bioactive compounds in the obtained extracts.

2.
Materials (Basel) ; 17(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38399069

RESUMO

Blast furnace dust waste (BFDW) proved efficient as a photocatalyst for the decolorization of methylene blue (MB) dye in water. Structural analysis unequivocally identified α-Fe2O3 as the predominant phase, constituting approximately 92%, with a porous surface showcasing unique 10-30 nm agglomerated nanoparticles. Chemical and thermal analyses indicated surface-bound water and carbonate molecules, with the main phase's thermal stability up to 900 °C. Electrical conductivity analysis revealed charge transfer resistance values of 616.4 Ω and electrode resistance of 47.8 Ω. The Mott-Schottky analysis identified α-Fe2O3 as an n-type semiconductor with a flat band potential of 0.181 V vs. Ag/AgCl and a donor density of 1.45 × 1015 cm-3. The 2.2 eV optical bandgap and luminescence stem from α-Fe2O3 and weak ferromagnetism arises from structural defects and surface effects. With a 74% photocatalytic efficiency, stable through three photodegradation cycles, BFDW outperforms comparable waste materials in MB degradation mediated by visible light. The elemental trapping experiment exposed hydroxyl radicals (OH•) and superoxide anions (O2-•) as the primary species in the photodegradation process. Consequently, iron oxide-based BFDW emerges as an environmentally friendly alternative for wastewater treatment, underscoring the pivotal role of its unique physical properties in the photocatalytic process.

3.
Nanomaterials (Basel) ; 13(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985876

RESUMO

Herein, we carefully investigated the Fe3+ doping effects on the structure and electron distribution of Cr2O3 nanoparticles using X-ray diffraction analysis (XRD), maximum entropy method (MEM), and density functional theory (DFT) calculations. We showed that increasing the Fe doping induces an enlargement in the axial ratio of c/a, which is associated with an anisotropic expansion of the unit cell. We found that as Fe3+ replaces Cr in the Cr2O3 lattice, it caused a higher interaction between the metal 3d states and the oxygen 2p states, which led to a slight increase in the Cr/Fe-O1 bond length followed by an opposite effect for the Cr/Fe-O2 bonds. Our results also suggest that the excitations characterize a well-localized bandgap region from occupied Cr d to unoccupied Fe d states. The Cr2O3 and Fe-doped Cr2O3 nanoparticles behave as Mott-Hubbard insulators due to their band gap being in the d-d gap, and Cr 3d orbitals dominate the conduction band. These findings suggest that the magnitude and the character of the electronic density near the O atom bonds in Cr2O3 nanoparticles are modulated by the Cr-Cr distances until its stabilization at the induced quasi-equilibrium of the Cr2O3 lattice when the Fe3+ doping values reaches the saturation level range.

4.
Microsc Res Tech ; 86(6): 731-741, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36974978

RESUMO

We have investigated the evolution of the structure and surface morphology of n-ZnO/p-ZnO homojunctions and n-ZnO/p-NiO heterojunctions transparent structures deposited by radio frequency-sputtering on quartz (Q)/ITO substrates. X-ray diffraction (XRD) analysis of the as-deposited and annealed ZnO, n-ZnO/p-NiO/Q/ITO, and n-ZnO/p-ZnO/Q/ITO thin films showed that ZnO had a wurtzite hexagonal structure and (002) preferred growth direction. The annealing temperature played a key role in improving the crystalline structure of the films, as evidenced by the changes in the intensity and position of the XRD (002) peak. Morphological analysis revealed that the roughness of the film varies with increasing annealing temperature. Particle size dictates the vertical growth of p-ZnO homojunctions, while particle shape dictated the p-NiO heterojunctions growth. Fractal analysis showed that p-ZnO homojunctions have similar spatial complexity, surface percolation, and topographical uniformity and are dominated by low dominant frequencies. Moreover, a robust multifractal character was observed, where n-ZnO/p-ZnO homojunctions follow similar vertical growth dynamics, which differed from the n-ZnO/p-NiO heterojunctions growth dynamics. These results prove that annealing temperature plays a key role in the n-ZnO/p-ZnO homojunctions and n-ZnO/p-NiO heterojunctions structure, surface morphology, and vertical growth dynamics.

5.
Materials (Basel) ; 15(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36363016

RESUMO

Iron niobates, pure and substituted with copper (Fe1-xCuxNbO4 with x = 0-0.15), were prepared by the solid-state method and characterized by X-ray diffraction, Raman spectroscopy, and magnetic measurements. The results of the structural characterizations revealed the high solubility of Cu ions in the structure and better structural stability compared to the pure sample. The analysis of the magnetic properties showed that the antiferromagnetic-ferromagnetic transition was caused by the insertion of Cu2+ ions into the FeNbO4 structure. The pure FeNbO4 structure presented an antiferromagnetic ordering state, with a Néel temperature of approximately 36.81K. The increase in substitution promoted a change in the magnetic ordering, with the state passing to a weak ferromagnetic order with a transition temperature (Tc) higher than the ambient temperature. The origin of the ferromagnetic ordering could be attributed to the increase in super-exchange interactions between Fe/Cu ions in the Cu2+-O-Fe3+ chains and the formation of bound magnetic polarons in the oxygen vacancies.

6.
Materials (Basel) ; 15(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36233887

RESUMO

FeSbO4 powder was prepared using the solid-state reaction method in this work. Afterward, the dense and porous ceramics were obtained by sintering the pressed powder calcined at temperatures of 900 and 1000 °C for 4 h. Rietveld profile analysis of the X-ray powder diffraction data showed that FeSbO4 adopts the trirutile-type structure (space group P42/mnm, with a ≅ 4.63 Å and c ≅ 9.23 Å). SEM images showed that the powder calcined at 900 °C after being sintered at 1200 °C resulted in ceramics of higher crystallinity, larger grains, and consequently, low porosity. The dielectric properties were measured in the frequency range of 10−1 Hz−1 MHz as a function of temperature (25−250 °C). The real (σ') and imaginary (σ″) parts of the complex conductivity increase with rising annealing temperature for both samples. The real conductivity in the AC region for 𝑓 = 100 kHz was 1.59×10−6 S·cm−1 and 7.04×10−7 S·cm−1 for the ceramic samples obtained from the powder calcined at 900 (C-900) and 1000 °C (C-1000), respectively. Furthermore, the dielectric constants (k') measured at room temperature and f=100 kHz were 13.77 (C-900) and 6.27 (C-1000), while the activation energies of the grain region were Ea = 0.53 eV and Ea = 0.49 eV, respectively. Similar activation energy (Ea = 0.52 eV and 0.49 eV) was also obtained by the brick-layer model and confirmed by the adjustment of activation energy by DC measurements which indicated an absence of the porosity influence on the parameter. Additionally, loss factor values were obtained to be equal to 3.8 (C-900) and 5.99 (C-1000) for measurements performed at 100 Hz, suggesting a contribution of the conductivity originated from the combination or accommodation of the pores in the grain boundary region. Our results prove that the microstructural factors that play a critical role in the electrical and dielectric properties are the average grain size and the porosity interspersed with the grain boundary region.

7.
Nanomaterials (Basel) ; 12(16)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36014752

RESUMO

ZnO nanocrystals with three different morphologies have been synthesized via a simple sol-gel-based method using Brosimum parinarioides (bitter Amapá) and Parahancornia amapa (sweet Amapá) latex as chelating agents. X-ray diffraction (XRD) and electron diffraction patterns (SAED) patterns showed the ZnO nanocrystals were a pure hexagonal wurtzite phase of ZnO. XRD-based spherical harmonics predictions and HRTEM images depicted that the nanocrystallites constitute pitanga-like (~15.8 nm), teetotum-like (~16.8 nm), and cambuci-like (~22.2 nm) shapes for the samples synthesized using bitter Amapá, sweet Amapá, and bitter/sweet Amapá chelating agent, respectively. The band gap luminescence was observed at ~2.67-2.79 eV along with several structural defect-related, blue emissions at 468-474 nm (VO, VZn, Zni), green emissions positioned at 513.89-515.89 (h-VO+), and orange emission at 600.78 nm (VO+-VO++). The best MB dye removal efficiency (85%) was mainly ascribed to the unique shape and oxygen vacancy defects found in the teetotum-like ZnO nanocrystals. Thus, the bitter Amapá and sweet Amapá latex are effective chelating agents for synthesizing distinctive-shaped ZnO nanocrystals with highly defective and remarkable photocatalytic activity.

8.
Sci Rep ; 12(1): 12002, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35835814

RESUMO

In this study, we investigated the morphology of synthesized Cu/Ni nanoparticles in trace of carbon sources by the co-deposition process of RF sputtering and RF-PECVD methods and localized surface plasmon resonance of CO gas sensing of Cu/Ni nanoparticles. The surface morphology was studied by analyzing 3D micrographs of atomic force microscopy using image processing techniques and fractal/multifractal analyses. The MountainsMap® Premium software with the two-way ANOVA (Variance analysis) and least-significant differences tests were used for statistical analysis. The surface nano-patterns have a local and global particular distribution. Experimental and simulated Rutherford backscattering spectra confirm the quality of nanoparticles. Then, prepared samples were exposed to CO gas flue to study their gas sensor application using the localized surface plasmon resonance method. Increasing the Ni layer over Cu one shows an interesting result in both morphology and gas sensing sides. Advanced stereometric analyses for the surface topography of thin films in conjunction with Rutherford backscattering spectrometry and Spectroscopic analysis make a unique study in the field.

9.
Bull Entomol Res ; 112(3): 389-398, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35543299

RESUMO

Non-crop plant diversity plays a fundamental role in the conservation of predatory mite (PM) and can be proposed as a banker plant system (BPS). BPSs provide plants that host natural enemies in greenhouses or field crops and may improve the efficiency of biological control. The aim of this study was to investigate if a diverse plant composition could be a suitable BPS for PMs in strawberry crops. A plant inventory characterized 22 species of non-crop plants harboring PMs. The most abundant PMs, in decreasing order, were Neoseiulus californicus, Neoseiulus anonymus, Euseius citrifolius, and Euseius concordis. PMs were randomly distributed among plants. We also found specific associations of Phytoseiidae species and phytophagous or generalist mites on plants. Due to this, four species were deemed suitable as banker plants: Capsicum sp., Leonurus sibiricus, Solanum americanum, and Urochloa mutica. Moreover, these plants combined a high PMs density and a low occurrence or absence of pest-mites. This study suggests shifting the traditional view that BPSs are composed of a limited number of species to use plant assemblages. This contributes to both conservation and augmentative biological control.


Assuntos
Fragaria , Ácaros , Tetranychidae , Animais , Controle Biológico de Vetores , Comportamento Predatório
10.
Microsc Res Tech ; 85(7): 2526-2536, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35312128

RESUMO

In this study, açaí-loaded kefir microbial films obtained in solutions containing demerara sugar, a low-cost and relatively organic sugar, were prepared. Environmental scanning electron microscopy (ESEM), atomic force microscopy (AFM), stereometric and multifractal analyses were applied to study the influence of the concentration of açaí over the surface morphology as well as its multifractal nature. The ESEM and AFM images showed that low concentrations of acai berry form surface covered by bacteria, while higher concentrations promote yeast growth. The autocorrelation function suggested that the degree of surface anisotropy changes as the concentration of açaí increases, while the Minkowski Functionals confirmed that the sample with the highest content has a different morphology than the samples containing 10-40 ml. The multifractal analysis revealed that the surfaces have a strong multifractal behavior, where the multifractal singularity strength was higher in the sample containing the highest concentration of açaí. The sample with the highest concentration was then mapped to have a greater vertical growth of its spatial patterns. These results prove that image analysis using mathematical tools can be very useful for the characterization of biological-based systems for application in the biomedicine field. We characterized the micromorphology of the 3D surface of the kefir biofilms associated with Acai extract. The 3D surface analysis of the samples was performed using by environmental scanning electron microscope and atomic force microscopy. We determined the multifractal and Minkowski Functionals of the analyzed samples.


Assuntos
Kefir , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Açúcares , Propriedades de Superfície
11.
Appl Immunohistochem Mol Morphol ; 29(10): e92-e100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34261975

RESUMO

Skin ulcers, wounds, or burns represent a burden for health care worldwide. Our aim was to explore the effects of mucoadhesive formulation with Curcuma longa L. extract mucoadhesive formulation containing curcumin (MFC) on skin healing in Wistar rats. Fifty-four rats were randomly allocated into 3 groups: control, vehicle, and MFC. A full-thickness circular wound was induced on the back of each animal. Two daily applications of the products were performed according to the experimental group. On days 3, 10, and 21, 6 animals in each group were euthanized. Clinical analysis was based on wound area. Histologic analysis was performed in hematoxylin and eosin-stained sections, with re-epithelization and inflammation being assessed by means of semiquantitative scores. To analyze the Akt/mTOR pathway, immunohistochemistry for phospho Akt (pAkt) and phospho ribosomal protein S6 were investigated. In addition, nuclear factor kappa-light-chain-enhancer of activated B cells immunolabeling was performed. Clinical analysis revealed wounds with a smaller area on days 3 and 10 in curcumin-treated animals. Histologically, MFC had a significant impact on inflammatory events on days 3 and 10 and promoted faster re-epithelization, which was evidenced on day 10. MFC-treated wounds exhibited pAkt upregulation on day 10 and both pAkt and phospho ribosomal protein S6 downregulation on day 21. Nuclear factor kappa-light-chain-enhancer of activated B cells expression varied through the evaluation periods; however, no significant difference was observed between groups. Collectively, our results indicate that MFC is efficient in accelerating cutaneous wound repair through modulation of the inflammatory process and stimulus of re-epithelization by an Akt/mTOR-dependent mechanism.


Assuntos
Curcuma/química , Regulação da Expressão Gênica/efeitos dos fármacos , NF-kappa B/biossíntese , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Imuno-Histoquímica , Masculino , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
12.
Inorg Chem ; 60(7): 4475-4496, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33710867

RESUMO

Defect influences on the photoactivity of ZnO nanoparticles prepared by a powdered coconut water (ACP) assisted synthesis have been studied. The crystalline phase and morphology of ZnO nanoparticles were effectively controlled by adjusting the calcination temperature (400-700 °C). An induced transition of hybrid Zn5(CO3)2(OH)6/ZnO nanoparticles to single-phase ZnO nanoparticles was obtained at 480 °C. The morphological analysis revealed a formation of ZnO nanoparticles with semispherical (∼6.5 nm)- and rod-like (∼96 nm) shapes when the calcination temperatures were 400 and 700 °C, respectively. Photoluminescence characterizations revealed several defects types in the samples with VZn and VO+ being in the self-assembly of semispherical- and rod-like ZnO nanoparticles. The photocatalytic activity of the ZnO nanoparticles was examined by assessing the degradation of methylene blue in an aqueous solution under low-intensity visible-light irradiation (∼3 W m-2). The results point toward the self-assembly of semispherical- and rod-like ZnO nanoparticles that had significantly better photocatalytic activity (∼31%) in comparison to that of spherical-agglomerated- or near-spherical-like species within 120 min of irradiation. The possible photocatalytic mechanism is discussed in detail, and the morphology-driven intrinsic [VZn+VO+] defects are proposed to be among the active sites of the ZnO nanoparticles enhancing the photocatalytic activity.

13.
Sao Paulo Med J ; 138(4): 297-304, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813846

RESUMO

BACKGROUND: The largest radiological accident to occur in any urban area happened in Goiânia, Brazil, in 1987. OBJECTIVE: To evaluate the association between breast cancer incidence and ionizing radiation levels. DESIGN AND SETTING: Ecological study among residents of the city of Goiânia, Brazil. METHODS: The central region of Goiânia, with seven major sources of contamination from cesium-137, was defined as the study area. The addresses of women diagnosed with breast cancer were identified between 2001 and 2010. The data were geographically referenced and, using census data, the annual averages of crude incidence rates were estimated. The existence of clusters of new cases was ascertained by means of the Moran index. Correlations of radiometric measurements with the incidence were assessed using unconditional linear regression. RESULTS: A total of 4,105 new cases were identified, of which 2,233 were in the study area, and of these, 1,286 (57.59%) were georeferenced. The gross rates of total and referenced cases were 102.91 and 71.86/100,000 women, respectively. These were close to the average for Brazilian state capitals, which is 79.37/100,000 women. The cluster analysis showed slight correlations in three small sets of census tracts, but these were far from the sources of contamination. The scatter plot of points and the R2 value close to zero indicated that there was no association between the variables. CONCLUSION: This study reinforces the hypothesis that the ionizing radiation levels to which women living in Goiânia are now exposed to are not associated with the onset of new cases of breast cancer.


Assuntos
Contaminação Radioativa do Ar/efeitos adversos , Neoplasias da Mama/epidemiologia , Mama/efeitos da radiação , Radioisótopos de Césio/efeitos adversos , Neoplasias Induzidas por Radiação/epidemiologia , Radiação Ionizante , Liberação Nociva de Radioativos , Adulto , Brasil/epidemiologia , Neoplasias da Mama/etiologia , Feminino , Humanos , Incidência , Medição de Risco , Fatores de Risco , Fatores de Tempo
14.
São Paulo med. j ; 138(4): 297-304, July-Aug. 2020. tab, graf
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: biblio-1139709

RESUMO

ABSTRACT BACKGROUND: The largest radiological accident to occur in any urban area happened in Goiânia, Brazil, in 1987. OBJECTIVE: To evaluate the association between breast cancer incidence and ionizing radiation levels. DESIGN AND SETTING: Ecological study among residents of the city of Goiânia, Brazil. METHODS: The central region of Goiânia, with seven major sources of contamination from cesium-137, was defined as the study area. The addresses of women diagnosed with breast cancer were identified between 2001 and 2010. The data were geographically referenced and, using census data, the annual averages of crude incidence rates were estimated. The existence of clusters of new cases was ascertained by means of the Moran index. Correlations of radiometric measurements with the incidence were assessed using unconditional linear regression. RESULTS: A total of 4,105 new cases were identified, of which 2,233 were in the study area, and of these, 1,286 (57.59%) were georeferenced. The gross rates of total and referenced cases were 102.91 and 71.86/100,000 women, respectively. These were close to the average for Brazilian state capitals, which is 79.37/100,000 women. The cluster analysis showed slight correlations in three small sets of census tracts, but these were far from the sources of contamination. The scatter plot of points and the R2 value close to zero indicated that there was no association between the variables. CONCLUSION: This study reinforces the hypothesis that the ionizing radiation levels to which women living in Goiânia are now exposed to are not associated with the onset of new cases of breast cancer.


Assuntos
Humanos , Feminino , Adulto , Radiação Ionizante , Mama/efeitos da radiação , Neoplasias da Mama/epidemiologia , Radioisótopos de Césio/efeitos adversos , Contaminação Radioativa do Ar/efeitos adversos , Neoplasias Induzidas por Radiação/epidemiologia , Fatores de Tempo , Brasil/epidemiologia , Neoplasias da Mama/etiologia , Incidência , Fatores de Risco , Medição de Risco , Liberação Nociva de Radioativos
15.
Asian Pac J Cancer Prev ; 20(6): 1857-1864, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31244310

RESUMO

Background: Factors that may hamper access to mammographic screening in any given region include socioeconomic limitations and the geographical distribution and quality of the mammography machines. This study evaluated access to breast cancer screening within the Brazilian National Health Service (SUS), the geographical distribution of mammography equipment and the number of mammograms performed in Brazil. Methods: This ecological study evaluated the availability of mammography machines within the SUS, those available for Brazil as a whole, its macroregions, states and the Federal District in 2016. The number of mammography machines required for breast cancer screening was calculated and compared to the number of machines available. The expected number of mammograms was compared with the actual number performed. Machines were georeferenced based on their location and the municipal seat, according to healthcare region, with 60 km being defined as the maximum distance for an individual to travel for a mammogram. Results: In 2016, there were 4,628 mammography machines in Brazil. Of these, 4,492 were in use and 2,113 (47%) were available to the SUS. Considering the number of mammograms required as a function of the number clinically indicated, 2,068 machines would be required for breast cancer screening in Brazil. The network of machines available would be capable of producing 14,279,654 exams; however, only 4,073,079 exams were performed, representing 29% of the total capacity of production in the country in 2016. Regarding the maximum distance of 60 km to access a mammogram, only relatively small areas of Brazil were found not to meet this indicator. Conclusion: These results suggest that the difficulty of the Brazilian population in accessing breast cancer screening through the SUS is not associated with the number of machines available or with the geographical location of the equipment but rather with the insufficient number of mammograms performed.


Assuntos
Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/tendências , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Idoso , Brasil/epidemiologia , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico
16.
Acta sci., Biol. sci ; 30(4): 379-390, 2008.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460556

RESUMO

Systematic surveys of the vegetative cover in Brazil include the semi-detailed mappings conducted within the scope of the Radam and Radambrasil projects, between 1971 and 1977, based on side-looking airborne radar images, and more recently, the assessments, based on Landsat 7 ETM+ imagery, of the remnant vegetation cover of the Brazilian biomes (MMA/PROBIO), finished in 2006. In a little more than 30 years, many changes have occurred, both in vegetation cover as well as in orbital remote sensing. In this review article, we discuss, from a conceptual and technological perspective, the evolution and the state of the art of imager sensors, as well as some of the enhancement techniques utilized for decoding (e.g., in biophysical parameters, etc.) and classifying the spectral response of vegetation. Likewise, we present the main current (pioneering) initiatives for land cover monitoring of the Brazilian biomes.


Levantamentos sistemáticos da cobertura vegetal no Brasil, à escala de semidetalhe, incluem aqueles realizados no âmbito dos projetos Radam e Radambrasil, no período de 1971 a 1977, tendo por base imagens de radar aerotransportadas e, mais recentemente, os mapeamentos, com base em imagens Landsat 7 ETM+, dos remanescentes da cobertura vegetal nos biomas brasileiros (projeto MMA/PROBIO), concluídos em 2006. Nestes pouco mais de 30 anos, muitas mudanças ocorreram, tanto na cobertura vegetal do país quanto no sensoriamento remoto orbital. Neste artigo de revisão, apresentamos, do ponto de vista conceitual e tecnológico, a evolução e o estado-da-arte dos sistemas sensores e discutimos algumas das técnicas mais utilizadas para decodificar (ex. em parâmetros biofísicos etc.) e classificar a resposta espectral da vegetação. Da mesma forma, apresentamos as principais iniciativas, históricas ou em curso, voltadas ao monitoramento da cobertura vegetal dos biomas brasileiros.

17.
Belo Horizonte; s.n; 2002. 51 p.
Tese em Português | BBO - Odontologia | ID: biblio-865377
18.
Rev. CROMG (Impr.) ; 8(1): 79-87, 2002. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-855730

RESUMO

É proposta uma nova técnica que permite a construção e instalação definitiva de uma prótese total fixa mandibular implanto-suportada em apenas 31 horas após instalação cirúrgica dos implantes


Assuntos
Prótese Total , Implantes Dentários
19.
Ciênc. rural ; 32(6): 1011-1017, 2002. tab
Artigo em Inglês | LILACS | ID: lil-330450

RESUMO

The hepatic megakaryocytic cells of New Zealand White rabbit in the intrauterine phase and in the immediate postnatal period were studied. Statistical analysis of the data concerning the cytoplasm and nucleus of those cells, i.e., area, perimeter, maximum diameter, minimum diameter, volume and shape factor, presented significant differences (p<0.01) for F values concerning the life phases studied on15th, 22nd and 29th day of intrauterine life and 10th day of postnatal life, and for F values for animal within each phase. The TukeyÆs test showed that most of the parameters studied in the cytoplasm and nucleus of these megakaryocytic cells presented the lowest values on the 15th day of intrauterine life and the highest on the 22nd day of the same phase

20.
Rev. CROMG (Impr.) ; 6(2): 94-8, maio-out. 2000. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-855700

RESUMO

Este relato descreve a ocorrência de uma lesão periapical inativa em um implante de titânio osseointegrado, a qual foi diagnosticada aproximadamente 16 meses após sua ativação e que apresentou-se assintomática durante aquele período. A lesão e a região do implante afetado foram removidas cirurgicamente


Assuntos
Apicectomia , Implantes Dentários
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