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Search Results: 1 - 10 of 1017580 matches for " A. M. C. R. P. F; Melo "
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Comparative Study of the Cephalic Index of the Population from the Regions of the North and South of Brazil
Alves,H. A; Santos,M. I. M. P; Melo,F. C. L; Wellington,R;
International Journal of Morphology , 2011, DOI: 10.4067/S0717-95022011000400050
Abstract: since the beginning of the century in various countries, investigations to determine the anthropometric characteristics of a population were carried out. the issue of miscegenation in brazil is of great importance in this study to define a population representative data on the cranial anthropometry. the large size of brazil, with 8.514.876 km2 leads to an investigation between the two extreme regions of the country: north and south, because of the ethnic composition of their colonizers. this study aims to investigate, compare and rank possible differences in cephalic index of the populations from these regions of brazil. therefore, an anthropometric study was performed at the school of aeronautics expert (single training center for graduates of brazilian air force), measurements were performed in 110 male students, divided by regions, and also the parents of these students who came from the same region of brazil. the average width of the head shown in the northern region is 15.80 ± 0.69 and 15.75 ± 0.53 in the southern region, with significant difference (p <0.05). the average length of the head lodged in the northern region is 19.54 ± 0.61 and 19.94 and in the south ± 0.67, significant difference (p <0.05). with respect to the cephalic index the average in the north is 80.93 ± 3.84 and in the south 79.06 ± 3.60, significant difference (p <0.05). in the northern region, for the classification, mesocephalic is predominant, but with a tendency to brachycephalic and hyperbrachycephalic, dolichocephalic type was rare in the south and the opposite occurs with respect to the rare type, the classification is to mesocephalic predominantly the second type is also brachycephalic, dolichocephalic but it is the third most common, often presented as the brachycephalic type.
Comparative Study of the Cephalic Index of the Population from the Regions of the North and South of Brazil Estudio Comparativo de índice Cefálico de la Población de las Regiones Norte y Sur de Brasil
H. A Alves,M. I. M. P Santos,F. C. L Melo,R Wellington
International Journal of Morphology , 2011,
Abstract: Since the beginning of the century in various countries, investigations to determine the anthropometric characteristics of a population were carried out. The issue of miscegenation in Brazil is of great importance in this study to define a population representative data on the cranial anthropometry. The large size of Brazil, with 8.514.876 km2 leads to an investigation between the two extreme regions of the country: North and South, because of the ethnic composition of their colonizers. This study aims to investigate, compare and rank possible differences in cephalic index of the populations from these regions of Brazil. Therefore, an anthropometric study was performed at the School of Aeronautics Expert (single training center for graduates of Brazilian Air Force), measurements were performed in 110 male students, divided by regions, and also the parents of these students who came from the same region of Brazil. The average width of the head shown in the Northern region is 15.80 ± 0.69 and 15.75 ± 0.53 in the Southern region, with significant difference (P <0.05). The average length of the head lodged in the Northern region is 19.54 ± 0.61 and 19.94 and in the South ± 0.67, significant difference (P <0.05). With respect to the cephalic index the average in the North is 80.93 ± 3.84 and in the South 79.06 ± 3.60, significant difference (P <0.05). In the Northern region, for the classification, mesocephalic is predominant, but with a tendency to brachycephalic and hyperbrachycephalic, dolichocephalic type was rare in the South and the opposite occurs with respect to the rare type, the classification is to mesocephalic predominantly the second type is also brachycephalic, dolichocephalic but it is the third most common, often presented as the brachycephalic type. Desde el comienzo del siglo en varios países, se llevaron a cabo investigaciones para determinar las características antropométricas de la población. El tema del mestizaje en Brasil es de gran importancia en este estudio para definir una base de datos representativa de la población en la antropometría craneal. El gran tama o de Brasil, con 8.514.876 km2 nos lleva a realizar una investigación en individuos pertenecientes a las dos regiones extremas del país: Norte y Sur, debido a la composición étnica de sus colonizadores. Este estudio tiene como objetivo investigar, comparar y clasificar las posibles diferencias en el índice cefálico de las poblaciones de estas regiones de Brasil. Por anterior, se llevó a cabo un estudio antropométrico en la Escuela de Aeronáutica de expertos (centro de entrenamie
Detection of White Spot Syndrome Virus in Brazil using Negative Staining, Immunoelectron Microscopy and Immunocytochemistry Techniques Detección del Virus del Síndrome de Mancha Blanca en el Brasil Utilizando Inmunomicroscopía e Inmunomarcación con Partículas de Oro Coloidal
M Hipolito,M. H. B Catroxo,A. M. C. R. P. F Martins,N.A Melo
International Journal of Morphology , 2012,
Abstract: In this study thirty shrimp samples from commercial marine shrimp (L. vannamei) farms of southern region of Brazil were obtained. Hepatopancreas and shell scrapings fragments collected in these animals were processed by transmission electron microscopy using negative staining (rapid preparation), immunoelectron microscopy and immunocytochemistry (immunolabelling with colloidal gold particles) techniques. On the transmission electron microscopy a great number of white spot virus particles, ovoid or bacilliform-to-ellipsoid, measured 230-290 nm in length and 80-160 nm in diameter with intra-nuclear projections were visualized by the negative staining technique in 27 (90%) out of 30 samples examined. Using immunoelectron microscopy technique, the anti-VP 664 serum agllutinated a large number of particles formed by antigen-antibody interaction. In the immunocytochemistry technique, the antigen-antibody reaction was styrongly marked by the particles of colloidal gold over the virus. Notably, this is the first report, to our knowledge, describing use of these microscopy techniques to study Brazilian L. vannamei marine shrimp samples; moreover, this methodology also appears to be a viable complementary tool for diagnosing the presence of the white spot virus within shrimp tissues. Importantly, these are the first photoelectron micrographs of the WSSV in Brazil. Se obtuvieron para el estudio 30 muestras de camarones marinos comerciales (L. vannamei) de las granjas de la región sur de Brasil. Fueron procesados fragmentos de hepatopáncreas y raspados internos del cefalotórax recogidos en estos animales por microscopía electrónica de transmisión con tinción negativa (preparación rápida), inmunomicroscopía y técnicas de inmunocitoquímica (inmunomarcación con partículas de oro coloidal). En la microscopía electrónica de transmisión de un gran número de partículas de virus de la mancha blanca, ovoide o elipsoidal a baciliformes, medían 230-290 nm de longitud y 80-160 nm de diámetro. En 27 (90%) de las 30 muestras examinadas intra-nuclear proyecciones se visualizaron mediante la técnica de tinción negativa. Utilizando una técnica de inmunomicroscopía electrónica, el anti-suero VP 664 reunió a un gran número de partículas formadas por la interacción antígeno-anticuerpo. En la técnica de inmunocitoquímica, la reacción antígeno-anticuerpo fue fuertemente reforzada por las partículas de oro coloidal en los virus. En particular, en Brasil este es el primer informe, a nuestro entender, que describe el uso de estas técnicas de microscopía en muestras de camarón marino L. van
Research of Viral Agent in Free-living Pigeon Feces (Columba livia) in the City of S?o Paulo, SP, Brazil, for Transmission Electron Microscopy
Catroxo,M. H. B; Martins,A. M. C. R. P. F; Petrella,S; Curi,N. A; Melo,N.A;
International Journal of Morphology , 2011, DOI: 10.4067/S0717-95022011000200055
Abstract: the pigeon feces are vehicle of diseases both for humans and other animal species. in these birds, the most important viral diseases of the digestive tract are transmitted by the paramyxovirus, adenovirus and coronavirus. avian paramyxoviruses have been isolated from a variety of species of free living and domestic birds worldwide, with several symptoms and clinical signs and economic losses. paramyxoviruses belong to the paramyxoviridae family and avulovirus genus that includes nine serotypes (apmv 1 to 9). avian adenoviruses belong to the adenoviridae family and aviadenovirus genus. in pigeons, cause classical adenovirosis and necrotizing hepatitis. the respiratory and enteric tracts are common targets of coronavirus. they belong to the coronaviridae family and to 3a and 3c groups. in this study, we described the presence of viral agents in free-living pigeon feces (columba livia) from the city of s?o paulo, brazil. the feces were processed by negative staining technique (rapid preparation) for transmission electron microscopy. in this technique paramyxoviruses particles, pleomorphic, roughly spherical or filamentous, measuring 100 to 500 nm of diameter containing an envelope covered by spikes, with characteristic helical herring-bone-like nucleocapsid, measuring 15 to 20 nm in diameter, were visualized in 45 (79%) out of 57 feces samples. in 2 (3.5%) samples, paramyxovirus and adenovirus particles were simultaneously visualized. adenovirus particles were isometric, spherical, characterized as "complete "or" empty ", measuring between 70 and 90 nm in diameter. paramyxovirus and coronavirus particles were detected in 3 (5.2%) samples. coronaviruses were pleomorphic with a diameter of 75-160 nm containing a solar corona-shaped envelope, with projections of approximately 20 nm of diameter. seven (12.3%) samples were negative for viral particles.
Search for associations containing young stars (SACY). V. Is multiplicity universal? Tight multiple systems
P. Elliott,A. Bayo,C. H. F. Melo,C. A. O. Torres,M. Sterzik,G. R. Quast
Physics , 2014, DOI: 10.1051/0004-6361/201423856
Abstract: Context: Dynamically undisrupted, young populations of stars are crucial to study the role of multiplicity in relation to star formation. Loose nearby associations provide us with a great sample of close ($<$150 pc) Pre-Main Sequence (PMS) stars across the very important age range ($\approx$5-70 Myr) to conduct such research. Aims: We characterize the short period multiplicity fraction of the SACY (Search for Associations Containing Young stars) accounting for any identifiable bias in our techniques and present the role of multiplicity fractions of the SACY sample in the context of star formation. Methods: Using the cross-correlation technique we identified double-lined spectroscopic systems (SB2), in addition to this we computed Radial Velocity (RV) values for our subsample of SACY targets using several epochs of FEROS and UVES data. These values were used to revise the membership of each association then combined with archival data to determine significant RV variations across different data epochs characteristic of multiplicity; single-lined multiple systems (SB1). Results: We identified 7 new multiple systems (SB1s: 5, SB2s: 2). We find no significant difference between the short period multiplicity fraction ($F_\mathrm{m}$) of the SACY sample and that of nearby star forming regions ($\approx$1-2 Myr) and the field ($F_\mathrm{m}\leq$10%) both as a function of age and as a function of primary mass, $M_1$, in the ranges $P$ [1:200 day] and $M_2$ [0.08 $M_{\odot}$-$ M_1$]. Conclusions: Our results are consistent with the picture of universal star formation, when compared to the field and nearby star forming regions (SFRs). We comment on the implications of the relationship between increasing multiplicity fraction with primary mass, within the close companion range, in relation to star formation.
Production of bone cement composites: effect of fillers, co-monomer and particles properties
Santos Jr., J. G. F.;Pita, V. J. R. R.;Melo, P. A.;Nele, M.;Pinto, J. C.;
Brazilian Journal of Chemical Engineering , 2011, DOI: 10.1590/S0104-66322011000200007
Abstract: artificial bone cements (bcs) based on poly(methyl methacrylate) (pmma) powders and methyl methacrylate (mma) liquid monomer also present in their formulation small amounts of other substances, including a chemical initiator compound and radiopaque agents. because inadequate mixing of the recipe components during the manufacture of the bone cement may compromise the mechanical properties of the final pieces, new techniques to incorporate the fillers into the bc and their effect upon the mechanical properties of bc pieces were investigated in the present study. pmma powder composites were produced in-situ in the reaction vessel by addition of x-ray contrasts to the reacting mma mixture. it is shown that this can lead to much better mechanical properties of test pieces, when compared to standard bone cement formulations, because enhanced dispersion of the radiopaque agents can be achieved. moreover, it is shown that the addition of hydroxyapatite (ha) and acrylic acid (aa) to the bone cement recipe can be beneficial for the mechanical performance of the final material. it is also shown that particle morphology can exert a tremendous effect upon the performance of test pieces, indicating that the suspension polymerization step should be carefully controlled when optimization of the bone cement formulation is desired.
Síntese e estudo microestrutural de perovsquitas tipo La0,8Ca0,2MO3 (M: Co e Mn) para aplica??o em catálise automotiva
Ribeiro, J. P.;Borges, F. M. M.;Pimentel, P. M.;Oliveira, R. M. P. B.;Melo, D. M. A.;Bicudo, T. C.;
Ceramica , 2011, DOI: 10.1590/S0366-69132011000300014
Abstract: materials with perovskite structure are potential catalysts for preventing greenhouse gas emissions to the environment. several methods have been proposed for the synthesis of these materials in order to produce homogeneous powders with nanometric particle size. in the present work, the la0.8ca0.2mno3 and la0.8ca0.2coo3 systems were prepared by the polymeric precursor method for application in automotive catalysis. this method was chosen because it allows obtaining homogeneous powders and crystalline phases at lower temperatures. the powders were calcined at 700 and 900 oc for 4 h and characterized by thermal analysis, x-ray diffraction and scanning electron microscopy techniques. the perovskites are nanometric, single phased and present suitable properties for use in automotive catalysis.
High-pressure Raman study of L-alanine crystal
A. M. R. Teixeira,P. T. C. Freire,A. J. D. Moreno,J. M. Sasaki,A. P. Ayala,J. Mendes Filho,F. E. A. Melo
Physics , 2000, DOI: 10.1016/S0038-1098(00)00342-2
Abstract: Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were carried out in L-alanine in order to investigate its external mode phonon spectra in relation to the phase transitions in the crystal. A careful analysis of the spectra shows that the low-energy Raman modes exhibit variation both in frequency and in intensity and between 26 and 28 kbar it is observed a splitting of a external mode, indicating that the D_2 normal phase undergoes a transition. Pressure coefficients for external modes are also given.
Catalisadores ceramicos de ZnAl2-xFe xO4: síntese de pós nanométricos e sua caracteriza??o
Lula, R. P. T.;Melo, P. S.;Barros, B. S.;Gama, L.;Mariano, W. A.;Kiminami, R. H. G. A.;Costa, A. C. F. M.;
Ceramica , 2005, DOI: 10.1590/S0366-69132005000200005
Abstract: in recent years, increasing interest has focused on direct catalytic sox reduction of elementary sulfur by several reducing agents such as co, methane and synthetic gases. mixed metallic oxides are an important class of catalytic materials investigated worldwide for application in a variety of fields. in this context, this work focused on the synthesis by combustion reaction and characterization of znal2-xfexo4 catalysts, x = 0.0, 0.75, 1.0, 1.25, 1.5, and 1.75. the resulting powders were characterized by their density and surface area measured by bet, x-ray diffraction and scanning electron microscopy. our findings indicate that single phase powders comprised of nanosized particles were obtained. increasing the amount of fe3+ ions replacing al3+ ions caused the surface area to increase, thereby reducing the particle size (82.74 - 30.94 nm). hence, the catalysts with a greater fe3+ content were found to perform well in reducing gas emissions from the oil industry.
Search for associations containing young stars (SACY). VI. Is multiplicity universal? Stellar multiplicity in the range 3-1000 au from adaptive-optics observations
P. Elliott,N. Huelamo,H. Bouy,A. Bayo,C. H. F. Melo,C. A. O. Torres,M. F. Sterzik,G. R. Quast,G. Chauvin,D. Barrado
Physics , 2015, DOI: 10.1051/0004-6361/201525794
Abstract: Context. Young loose nearby associations are unique samples of close (<150 pc), young (approx 5-100 Myr) pre-main sequence (PMS) stars. A significant number of members of these associations have been identified in the SACY collaboration. We can use the proximity and youth of these members to investigate key ingredients in star formation processes, such as multiplicity. Aims. We present the statistics of identified multiple systems from 113 confirmed SACY members. We derive multiplicity frequencies, mass-ratio, and physical separation distributions in a consistent parameter space, and compare our results to other PMS populations and the field. Methods. We have obtained adaptive-optics assisted near-infrared observations with NACO (ESO/VLT) and IRCAL (Lick Observatory) for at least one epoch of all 113 SACY members. We have identified multiple systems using co-moving proper-motion analysis and using contamination estimates. We have explored ranges in projected separation and mass-ratio of a [3-1000 au], and q [0.1-1], respectively. Results. We have identified 31 multiple systems (28 binaries and 3 triples). We derive a multiplicity frequency (MF) of MF_(3-1000au)=28.4 +4.7, -3.9% and a triple frequency (TF) of TF_(3-1000au)=2.8 +2.5, -0.8% in the separation range of 3-1000 au. We do not find any evidence for an increase in the MF with primary mass. The estimated mass-ratio of our statistical sample (with power-law index gamma=-0.04 +/- 0.14) is consistent with a flat distribution (gamma = 0). Conclusions. We show further similarities (but also hints of discrepancies) between SACY and the Taurus region: flat mass-ratio distributions and statistically similar MF and TF values. We also compared the SACY sample to the field (in the separation range of 19-100 au), finding that the two distributions are indistinguishable, suggesting a similar formation mechanism.
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