Principal components in the study of soil and plant properties in precision coffee farming

ArticleIn this work, a principal component analysis was performed to evaluate the possibility of discarding obsolete soil and plant variables in a coffee field to eliminate redundant and difficult-to-measure information in precision coffee farming. This work was conducted at Brejão Farm in Três Pontas, Minas Gerais, Brazil, in a coffee field planted with 22 ha of Topázio cultivar. The evaluated variables were the yield, plant height, crown diameter, fruit maturation index, degree of fruit maturation, leafing, soil pH, available phosphorus (P), remaining phosphorus (Prem), available potassium (K), exchangeable calcium (Ca2+), exchangeable magnesium (Mg2+), exchangeable acidity (Al3+), potential acidity (H + Al), aluminium saturation (N(Al)), potential CEC (CECp), actual CEC (CECa), sum of bases (SB), base saturation (BS) and organic matter (OM). The data were evaluated by a principal component analysis, which generated 20 components. Of these, 7 representing 88.98% of the data variation were chosen. The variables were discarded based on the preservation of the variables with the greatest coefficients in absolute values corresponding to the first component, followed by the variable with the second highest absolute value corresponding to the second principal component. Based on the results, the variables V, OM, fruit maturity index, plant height, yield, leafing and P were selected. The other variables were discarded

Spatial variability of litter temperature, relative air humidity and skin temperature of chicks in a commercial broiler house

ArticleThe thermal environment inside a broiler house has a great influence on animal welfare and productivity during the production phase. Among the importance of the chicken litter is the function of absorbing moisture, provide thermal insulation and provide a soft surface for broilers. The skin temperature is an important physiological parameter to quantify the thermal comfort of animals, its variations may occur as a function of thermal variables. So, the aim of this work was to analyse the magnitude and spatial variability of chicken litter temperature and relative humidity of the air and to correlate them with the spatial distribution of chicks’ skin surface temperature throughout the broiler house during the 7th, 14th and 21st days of the chicks’ life, using geostatistical techniques. The experiment was performed in a commercial broiler house located in the western mesoregion of Minas Gerais, Brazil, where 28,000 male Cobb chicks were housed. The heating system consisted of an industrial indirect-fired biomass furnace. The heated air was inflated by an AC motor, 2,206 W of power, 1,725 RPM. Geostatistical techniques were used through semivariogram analysis and isochore maps were generated through data interpolation by kriging. The semivariogram was fitted by the restricted maximum likelihood method. The used mathematical model was the spherical one. After fitting the semivariograms, the data were interpolated by ordinary kriging. The semivariograms along with the isochore maps allowed identifying the non-uniformity of spatial distribution of the broiler litter temperature throughout the broiler house for 3 days of chicks’ life. It was observed that skin surface presented a positive correlation with the litter temperature and a negative correlation with the air humidity. The semivariograms along with the isochore maps allowed identifying the non-uniformity of spatial distribution of the litter temperature, air humidity and skin temperature of chicks throughout the broiler aviary for the three days. In addition, the use of geostatistics and distribution maps made possible to identify different environmental conditions in regions inside the broiler house that may harm the development of chicks

RGB vegetation indices applied to grass monitoring: a qualitative analysis

ArticleIn developing countries such as Brazil, research on low-cost remote sensing and computational techniques become essential for the development of precision agriculture (PA), and improving the quality of the agricultural products. Faced with the scenario of increasing production of emerald grass (Zoysia Japônica) in Brazil, and the value added the quality of this agricultural product. The objective of this work was to evaluate the performance of RGB (IV) vegetation indices in the identification of exposed soil and vegetation. The study was developed in an irrigated area of 58 ha cultivated with emerald grass at Bom Sucesso, Minas Gerais, Brazil. The images were obtained by a RGB digital camera coupled to an remotely piloted aircraft. The flight plan was setup to take overlapping images of 70% and the aircraft speed was 10 m s -1 . Six RGB Vegetation index (MGVRI, GLI, RGBVI, MPRI, VEG, ExG) were evaluated in a mosaic resulting from the images of the study area. All of the VIs evaluated were affected by the variability of lighting conditions in the area but MPRI and MGVRI were the ones that presented the best results in a qualitative evaluation regarding the discrimination of vegetation and soil

Design and construction of a low-cost remotely piloted aircraft for precision agriculture applications

ArticleThis study aimed to construct a low cost RPA capable of recording georeferenced images. For the construction of the prototype of a quadcopter type RPA, only essential materials were used to allow stable flight. A maximum total weight of 2 kg was stipulated, including frame weight, electronic components, motors and cameras. The aircraft was programmed using a low-cost microcontroller widely used in prototyping and automation research. An electronic circuit board is designed to facilitate the connection of the microcontroller with the other components of the design. Specific software was used for flight control. The prototype was built successfully, being able to lift stable and controllable flight. However, we still need to acquire equipment and programming components capable of enabling autonomous images and flights. The final cost of the RPA was on average $427.00 on average 50in the Brazilian ARP market ($ 772.81 to $ 1,288.00

Applications of Bioceramics in the Management of Orbital Floor Fractures and Anophthalmic Cavity: A Review

Biocompatible ceramics, commonly known as “bioceramics”, are an extremely versatile class of materials with a wide range of applications in modern medicine. Given the inorganic nature and physico-mechanical properties of most bioceramics, which are relatively close to the mineral phase of bone, orthopedics and dentistry are the preferred areas of usage for such biomaterials. Another clinical field where bioceramics play an important role is oculo-orbital surgery, a highly cross-and interdisciplinary medical specialty addressing to the management of injured eye orbit, with particular focus on the repair of orbital bone fractures and/or the placement of orbital implants following removal of a diseased eye. In the latter case, orbital implants are not intended for bone repair but, being placed inside the ocular cavity, have to be biointegrated in soft ocular tissues. This article reviews the state of the art of currently-used bioceramics in orbital surgery, highlighting the current limitations and the promises for the future in this field

Capybara (Hydrochoerus hydrochaeris) distribution in agroecosystems: a cross-scale habitat analysis.

Made available in DSpace on 2018-06-05T00:41:40Z (GMT). No. of bitstreams: 1 ID278041.pdf: 606577 bytes, checksum: 40bd9735a50e8fafb25cc96dca81c57a (MD5) Previous issue date: 2007-01-0

Chirikov Diffusion in the Asteroidal Three-Body Resonance (5,-2,-2)

The theory of diffusion in many-dimensional Hamiltonian system is applied to asteroidal dynamics. The general formulations developed by Chirikov is applied to the Nesvorn\'{y}-Morbidelli analytic model of three-body (three-orbit) mean-motion resonances (Jupiter-Saturn-asteroid system). In particular, we investigate the diffusion \emph{along} and \emph{across} the separatrices of the (5,-2,-2) resonance of the (490) Veritas asteroidal family and their relationship to diffusion in semi-major axis and eccentricity. The estimations of diffusion were obtained using the Melnikov integral, a Hadjidemetriou-type sympletic map and numerical integrations for times up to $10^{8}$ years.Comment: 27 pages, 6 figure

Descriptive analysis of copy number variation regions in a population of dairy Gyr cattle.

The aim of this work was to investigate, based on a high density BovineHD SNP array, the abundance and distributions of CNVs and CNVR in a Gyr cattle population from Brazil. Genotype data of representative bulls were recorded, totaling 476 Gyr animals. For CNV identification was used the PennCNV software and the CNVRs were determined by the CNVRuler software. A total of 26,672 CNVs were found, beingon average 62 CNV per animal. Also, 1,898 CNVRs were detected on the autosomal chromosomes. Also, 1,898 CNVRs were detected on the autosomal chromosomes with 96% of these between 1.1 Kb to 100 Kb. The Ensembl's VEP tool, using the CNVRs information as input, found 913 coding regions, suggesting that exon regions were duplicated. In summary, the results help to better understand the Gyr genome and suggest that CNVRs might have some relationship with production traits.WCGALP 2014

Descriptive analysis of copy number variation regions in a population of dairy Gyr cattle.

The aim of this work was to investigate, based on a high density BovineHD SNP array, the abundance and distributions of CNVs and CNVR in a Gyr cattle population from Brazil. Genotype data of representative bulls were recorded, totaling 476 Gyr animals. For CNV identification was used the PennCNV software and the CNVRs were determined by the CNVRuler software. A total of 26,672 CNVs were found, beingon average 62 CNV per animal. Also, 1,898 CNVRs were detected on the autosomal chromosomes. Also, 1,898 CNVRs were detected on the autosomal chromosomes with 96% of these between 1.1 Kb to 100 Kb. The Ensembl's VEP tool, using the CNVRs information as input, found 913 coding regions, suggesting that exon regions were duplicated. In summary, the results help to better understand the Gyr genome and suggest that CNVRs might have some relationship with production traits

Phenotypic plasticity of composite beef cattle performance using reaction norms model with unknown covariate.

The objective of the present study was to determine the presence of genotype by environment interaction (G × E) and to characterize the phenotypic plasticity of birth weight (BW), weaning weight (WW), postweaning weight gain (PWG) and yearling scrotal circumference (SC) in composite beef cattle using the reaction norms model with unknown covariate. The animals were born between 1995 and 2008 on 33 farms located throughout all Brazilian biomes between latitude −7° and −31°, longitude −40° and −63°. The contemporary group was chosen as the environmental descriptor, that is, the environmental covariate of the reaction norms. In general, higher estimates of direct heritability were observed in extreme favorable environments. The mean of direct heritability across the environmental gradient ranged from 0.05 to 0.51, 0.09 to 0.43, 0.01 to 0.43 and from 0.12 to 0.26 for BW, WW, PWG and SC, respectively. The variation in direct heritability observed indicates a different response to selection according to the environment in which the animals of the population are evaluated. The correlation between the level and slope of the reaction norm for BW and PWG was high, indicating that animals with higher average breeding values responded better to improvement in environmental conditions, a fact characterizing a scale of G × E. Low correlation between the intercept and slope was obtained for WW and SC, implying re-ranking of animals in different environments. Genetic variation exists in the sensitivity of animals to the environment, a fact that permits the selection of more plastic or robust genotypes in the population studied. Thus, the G × E is an important factor that should be considered in the genetic evaluation of the present population of composite beef cattle.Firstview article 27 set. 2012