17 results on '"R. S. Mendes"'
Search Results
2. Microbial Hydroxylation of Sclareol by Rhizopus Stolonifer
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J. G. Urones, P. Basabe, I. S. Marcos, C. Paulino, R. S. Mendes, P. M. Rocha, J. M. Rodilla, J. M. Sanchez, and D. DÃÂez
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Sclareol ,Rhizopus stolonifer ,3β-hydroxy-sclareol ,18-hydroxy-sclareol ,Organic chemistry ,QD241-441 - Abstract
Incubation of sclareol with Rhizopus stolonifer affords in high yield a mixture of triols with 18-hydroxy-sclareol as the main component.
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- 2005
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3. Strong subadditivity lower bound and quantum channels.
- Author
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Leandro R. S. Mendes and Marcos César de Oliveira 0002
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- 2022
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4. Use of aerial image in the estimation of volume and biomass of Eucalyptus sp. forest stand
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Eraldo Aparecido Trondoli Matricardi, Mauro Eloi Nappo, Pedro Guilherme de Andrade Vasconcelos, Alba Valéria Rezende, Humberto Angelo, Thallita R. S. Mendes, Marco Bruno Xavier Valadão, Alcides Gatto, and Eder Pereira Miguel
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Volume (thermodynamics) ,Remote sensing (archaeology) ,Environmental science ,Biomass ,Satellite imagery ,Plant Science ,Agronomy and Crop Science ,Eucalyptus ,Aerial image ,Normalized Difference Vegetation Index ,Remote sensing ,Basal area - Abstract
Assessing forest stands is crucial for managing and planning the use of these resources. Forest inventory is the instrument that provides information about the stand situation, which can be costly and time consuming. In order to facilitate and reduce the time spent obtaining these data, the main objective of this work was to evaluate the accuracy of volume and biomass estimates per unit area with data from remote sensing. Forty sample units were allocated and georeferenced, in which all trees with diameter at breast height (DBH) ≥ 5 cm were inventoried. Sequentially, the cubage was performed in order to obtain individual biomass, volume, and adjustment of the individual models. With data from georeferenced images of the study area, the vegetation indices MSAVI (Modified Soil-Adjusted Vegetation Index) and NDVI (Normalized Difference Vegetation Index) were obtained. The volume and biomass estimation using remote sensing variables were carried out through the adjustment of sigmoidal models by regression analysis, which used a combination of the average values of the vegetation indices and the basal area of the plot/hectares as an independent variable. The fit statistics and the accuracy of the tested models presented consistent results to estimate forest production. The results showwd that indices derived from remote sensing techniques associated with forest variables information could accurately estimate the volume and biomass of Eucalyptus spp. plantations.
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- 2020
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5. Cisto de Inclusão Epidérmica em Situação Pré-Sacral: Um Relato de Caso
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L. P. Zollinger, C. R. S. Mendes, D. B. Vieira, L. A. Pereira, R. C. Barbosa, and A. J. D. Filho
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- 2021
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6. Cirurgia Ambulatorial para Endometriose Profunda com Ressecção Intestinal: É Possível?
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C. R. S. Mendes and M. A. M. Travessa
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- 2021
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7. Fuel material in quantification burlap planting of Tectona grandis Linn.F
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J. C. H. Santos, M. Sabino, A. T. P. Bortolini, A. G. M. F. Silva, A. P. Machado Neto, B. R. S. Mendes, D. P. Mata, D. Z. Araujo, and M. L. Pirolla
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lcsh:A ,lcsh:General Works ,fire, litter, sheets, miscellaneous - Abstract
This study aimed to evaluate the quantity and fuel moisture content material deposited in planting of Tectona grandis Linn.F with 20 years in the municipality of Sinop - MT. In the study area were installed five plots of 1 m2 within which collected up all the material above ground. The collected material was separated and weighed according to their type (green or dry) and class (leaf, miscellaneous, and branches 7, 6 cm). 100 g were taken. material from each plot to determine the moisture content in the laboratory after drying in an oven at 75 ° C for 48 hours. The experimental design was completely randomized in a factorial 2x7 (Type X Class) in 5 repetitions, significant means were compared by Tukey at 5% probability. Found 23.2 t ha-1 of dry combustible material in the area. There was no green material because the light conditions caused the tops of planting. There was a significant difference in the amount of combustible material in each class. Classes leaves and miscellany excelled presenting 8.37 Mg ha-1 and 10.29 t ha-1, respectively. Due to the climatic conditions of the season collects a 65.82% moisture content of the material was found.
- Published
- 2017
8. Time as a consequence of internal coherence
- Author
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Leandro R. S. Mendes and Diogo O. Soares-Pinto
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Work (thermodynamics) ,Quantum Physics ,010308 nuclear & particles physics ,Computer science ,General Mathematics ,General Engineering ,Measure (physics) ,FOS: Physical sciences ,General Physics and Astronomy ,Coherence (statistics) ,01 natural sciences ,Character (mathematics) ,INFORMAÇÃO QUÂNTICA (TEORIA) ,0103 physical sciences ,Statistical physics ,Quantum Physics (quant-ph) ,010306 general physics ,Quantum thermodynamics ,Quantum ,Mechanism (sociology) ,Coherence (physics) ,Research Article - Abstract
Time has been an elusive concept to grasp. Although we do not yet understand it properly, there have been advances made in regard to how we can explain it. One such advance is the Page–Wootters mechanism. In this mechanism, time is seen as an inaccessible coordinate and the apparent passage of time arises as a consequence of correlations between the subsystems of a global state. Here we propose a measure that captures the relational character of the mechanism, showing that the internal coherence is the necessary ingredient for the emergence of time in the Page–Wootters model. Also, we connect it to results in quantum thermodynamics, showing that it is directly related to the extractable work from quantum coherence.
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- 2019
9. Modeling Biomass and Nutrients in a Eucalyptus Stand in the Cerrado
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Thallita R. S. Mendes, Daniel Alves Vieira, Maísa Isabela Rodrigues, Alcides Gatto, Eder Pereira Miguel, Mirella Basileu de Oliveira Lima, Jonas Inkotte, Marco Bruno Xavier Valadão, Renan Augusto Miranda Matias, Fabiana Piontekowski Ribeiro, and Karla Monique Silva Carneiro
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Nutrient cycle ,aerial biomass ,non-linear model ,food and beverages ,Biomass ,nutrient cycling ,Forestry ,lcsh:QK900-989 ,Biomassa ,complex mixtures ,Eucalyptus ,Schumacher–Hall model ,Basal area ,Modelos matemáticos ,Nutrient ,Ciclagem de nutrientes ,Agronomy ,Soil water ,lcsh:Plant ecology ,Environmental science ,Soil fertility ,Silviculture - Abstract
The prediction of biological processes, which involve growth and plant development, is possible via the adjustment of mathematical models. In forest areas, these models assist in management practices, silviculture, harvesting, and soil fertility. Diameter, basal area, and height are predictors of volume and biomass estimates in forest stands. This study utilized different non-linear models for estimating biomass and nutrient values in the aerial biomass and roots of an unmanaged eucalypt stand in Cerrado dystrophic soil. It was hypothesized that the models would estimate the nutrients of the aboveground biomass and roots after meeting the selection and validation criteria. By statistical analysis of the parameters and subsequent validation, the Schumacher&ndash, Hall model was presented to be the best fit for biomass and nutrients. This result confirmed the ability of different variables, including diameter, basal area, and height, to be predicted. Estimating the nutrient values in the aboveground biomass and roots allowed a better understanding of the quality of the vegetal residues that remained in the soil. For dystrophic soils, which occur in the Cerrado, these estimates become even more relevant.
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- 2020
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10. Hábitos alimentares de estudantes de uma universidade pública no nordeste, Brasil Food habits of students of one public university of Northeast, Brazil
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E. P .S. FEITOSA, C. A. O. DANTAS, E. R. S. ANDRADE-WARTHA, P. S. MARCELLINI, and R. S. MENDES-NETTO
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hábitos alimentares, estado nutricional, estudantes universitários ,lcsh:TX341-641 ,lcsh:Nutrition. Foods and food supply - Abstract
Hábitos alimentares de universitários apresentam-se na maioria das vezes inadequados, caracterizado pelo baixo consumo de frutas e verduras e alta ingestão de alimentos ricos em gorduras e açúcares. Dessa forma, este grupo apresenta um maior risco de contrair doenças crônicas não transmissÃveis (DCNT). Diante disso, o propósito deste estudo foi avaliar os hábitos alimentares de estudantes universitários da UFS. Foram entrevistados, , 718 universitários dos cursos das áreas de exatas (300), humanas (180) e saúde (238), O instrumento utilizado para coleta de dados foi uma adaptação do questionário do Ministério da Saúde, além do da auto-referição do peso e da estatura. Os resultados mostraram que a maioria (69,6%) dos universitários encontrava-se eutróficos e 17,9% com excesso de peso (principalmente entre os homens, p
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- 2010
11. Spatial and temporal variability of canopy cover and understory light in a Cerrado of Southern Brazil
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José P. Lemos-Filho, Gisele P. M. Dantas, Lucimar G. Dias, C F A Barros, and R S Mendes
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Wet season ,Canopy ,Biology ,Trees ,seedling growth ,lcsh:Botany ,lcsh:Zoology ,Dry season ,Botany ,lcsh:QL1-991 ,Leaf area index ,lcsh:Science ,lcsh:QH301-705.5 ,photosynthesis ,leaf area index ,Understory ,Photosynthetic capacity ,lcsh:QK1-989 ,Plant Leaves ,tropical savanna ,lcsh:Biology (General) ,Agronomy ,Seedlings ,Photosynthetically active radiation ,Sunlight ,lcsh:Q ,Spatial variability ,Seasons ,Lambert-Beer ratio ,General Agricultural and Biological Sciences ,Brazil - Abstract
Canopy cover has significant effects on the understory environment, including upon light availability for seedling growth. The aim of the present study was to verify spatial heterogeneity and seasonal changes in the canopy cover of a dense Cerrado area, and their relationship to understory photosynthetic active radiation availability. Leaf area index (LAI) values in the rainy season varied from 0.9 to 4.83, with 40% of the values ranging from 4.0 to 5.0, while in the dry season LAI varied from 0.74 to 3.3, with 53% of the values oscillating from 2.0 to 3.0. Understory light (Q(i)) and the Lambert-Beer ratio (Q(i)/Q(o)) were taken around noon on sunny days (between 11:00 AM and 1:00 PM). They were also statistically different (p0.01) between the dry and wet seasons, with 72% of sampled points in the rainy season presenting photosynthetic photon flux density (PPFD) values lower than 250 micromol x m(-2)/s around noon, whereas in the dry season, most PPFD values varied from 1500 to 1817 micromol x m(-2)/s, thus providing high light availability for understory plants. In most of the studied sites, understory plants did not even receive enough light for 50% of their photosynthetic capacity in the wet season. In contrast during the dry season, Q(i)/Q(o) values of 0.8 to 1.0 were observed in more than 50% of the points, thereby allowing for photosynthetic light saturation. Thus, light variability around noon was higher during the dry season than in the wet season, its heterogeneity being related to spatial complexity in the canopy cover.
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- 2010
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12. STOCHASTIC QUANTIZATION AND 1/N EXPANSION
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R. S. Mendes and J. C. Brunelli
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Physics ,Nuclear and High Energy Physics ,Nonlinear system ,Field (physics) ,General Physics and Astronomy ,Astronomy and Astrophysics ,Perturbation theory ,Stochastic quantization ,1/N expansion ,Mathematical physics - Abstract
We study the 1/N expansion of field theories in the stochastic quantization method of Parisi and Wu using the supersymmetric functional approach. This formulation provides a systematic procedure to implement the 1/N expansion which resembles the ones used in the equilibrium. The 1/N perturbation theory for the nonlinear sigma-model in two dimensions is worked out as an example.
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- 1993
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13. Attractive forces between electrons in (2+1)-dimensional QED
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M. Gomes, R. S. Mendes, A. J. da Silva, H. O. Girotti, Jorge L. deLyra, and J. R. Nascimento
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Physics ,Particle physics ,Photon ,High Energy Physics::Lattice ,High Energy Physics::Phenomenology ,Massive particle ,General Physics and Astronomy ,Propagator ,Electron ,Vector boson ,Quantum mechanics ,Bound state ,Vacuum polarization ,Boson - Abstract
Vacuum polarization effects are nonperturbatively incorporated into the photon propagator to eliminate the severe infrared problems characteristic of (2+1)-dimensional QED (${\mathrm{QED}}_{3}$). The theory is thus rephrased in terms of a massive vector boson whose mass is ${\mathit{e}}^{2}$/8\ensuremath{\pi}. Subsequently, it is shown that electron-electron bound states are possible on ${\mathrm{QED}}_{3}$.
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- 1992
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14. Laboratory and field analysis on the tribological behavior of coated and uncoated forming tools
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R. M. Souza, M. A. R. S. Mendes, Yves Berthier, P. K. Vencovsky, Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne] (LaMCoS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
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Materials science ,Metallurgy ,chemistry.chemical_element ,Adhesion ,Tribology ,engineering.material ,chemistry ,Coating ,Physical vapor deposition ,visual_art ,visual_art.visual_art_medium ,engineering ,General Materials Science ,Galling ,Thin film ,Sheet metal ,Tin ,ComputingMilieux_MISCELLANEOUS - Abstract
Frequently, the life of the tools used in sheet metal forming operations is determined by a phenomenon known as galling, which originates from the adhesion of the sheet to the forming tool surface. The application of coating architectures composed by single or multiple layers of Physical Vapor Deposition (PVD) films, such as TiN, TiCN, CrN, TiCNAl, may significantly reduce the chemical interaction in the contact, up to the point that no significant adhesion may be observed for an extended number of forming operations. Usually, the evaluation of the behavior of different thin film architectures is conducted using tribometers that may or may not reproduce the conditions found in industrial practice. This work presents a tribological analysis of coated and uncoated surfaces of tools used in industrial sheet metal forming operations and discusses the capability of laboratory tests in reproducing the situations found in practice.
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- 2008
15. Quantum Corrections for Generalized Partition Functions
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R. S. Mendes, Rua Xavier Sigaud, Luiz Roberto Evangelista, and L. C. Malacarne
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Statistics and Probability ,Work (thermodynamics) ,Condensed Matter (cond-mat) ,FOS: Physical sciences ,Coherent states ,Order (group theory) ,Statistical mechanics ,Statistical physics ,Condensed Matter ,Condensed Matter Physics ,Quantum ,Classical limit ,Mathematics - Abstract
The classical limit for generalized partition functions is obtained using coherent states. In this framework it is presented a general procedure to obtain all the corrections to the classical limit. In particular, the first and second order quantum corrections are worked out explicitly, and the classical limit for the Tsallis thermostatistics is determined. The results of this work generalize the ones obtained by E. Wigner (Phys. Rev. 40 (1932) 749) for usual statistical mechanics., latex, 12 pages, to appears in Phys. A
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- 1998
16. Spatial correlations, clustering and percolation-like transitions in homicide crimes.
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L. G. A. Alves, E. K. Lenzi, R. S. Mendes, and H. V. Ribeiro
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The spatial dynamics of criminal activities has been recently studied through statistical physics methods; however, models and results have been focusing on local scales (city level) and much less is known about these patterns at larger scales, e.g. at a country level. Here we report on a characterization of the spatial dynamics of the homicide crimes along the Brazilian territory using data from all cities in a period of more than thirty years. Our results show that the spatial correlation function in the per capita homicides decays exponentially with the distance between cities and that the characteristic correlation length displays an acute increasing trend in the latest years. We also investigate the formation of spatial clusters of cities via a percolation-like analysis, where clustering of cities and a phase-transition–like behavior describing the size of the largest cluster as a function of a homicide threshold are observed. This transition-like behavior presents evolutive features characterized by an increasing in the homicide threshold (where the transitions occur) and by a decreasing in the transition magnitudes (length of the jumps in the cluster size). We believe that our work sheds new light on the spatial patterns of criminal activities at large scales, which may contribute for better political decisions and resources allocation as well as opens new possibilities for modeling criminal activities by setting up fundamental empirical patterns at large scales. [ABSTRACT FROM AUTHOR]
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- 2015
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17. Non-Gaussian center-of-pressure velocity distribution during quiet stance.
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E. S. D. Santos, S. Picoli, R. S. Mendes, and P. P. Deprá
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In the present study, we investigate patterns in the postural sway that characterize the static balance in human beings. To measure the postural sway, sixteen healthy young subjects performed quiet stance tasks providing the center-of-pressure (COP) trajectories. From these trajectories, we obtained the COP velocities. We verified that the velocity distributions exhibit non-normal behavior and can be approximated by generalized Gaussians with fat tails. We also discuss possible implications of modeling COP velocity by using generalized Fokker-Planck equations related to Tsallis statistics and Richardson anomalous diffusion. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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