1,057 research outputs found
Normas DRIS multivariadas para avaliação do estado nutricional de laranjeira 'Pera' no estado do Amazonas.
Para utilização da diagnose da composição nutricional ou do sistema integrado de diagnose e recomendação de relações multivariadas (DRIS) na avaliação do estado nutricional de laranjeira, faz-se necessário a definição de valores de referência que sejam adequados para refletir suas condições nutricionais. Neste trabalho, objetivou-se estabelecer normas DRIS multivariadas e avaliar seu desempenho comparativamente aos padrões nutricionais definidos pela literatura na avaliação do estado nutricional de laranjeiras 'Pera' no estado do Amazonas. Avaliou-se o estado nutricional de 120 glebas comerciais de laranjeira 'Pera' enxertadas em limoeiro 'Cravo', sendo que os padrões de referência foram definidos a partir do conjunto das glebas. O diagnóstico nutricional pelo método DRIS conjugado a utilização de normas genéricas comparativamente aos padrões nutricionais propostos pela literatura apresentou baixo grau de concordância na avaliação do estado nutricional de laranjeira 'Pera' no estado do Amazonas
Soft-Collinear Factorization in Effective Field Theory
The factorization of soft and ultrasoft gluons from collinear particles is
shown at the level of operators in an effective field theory. Exclusive
hadronic factorization and inclusive partonic factorization follow as special
cases. The leading order Lagrangian is derived using power counting and gauge
invariance in the effective theory. Several species of gluons are required, and
softer gluons appear as background fields to gluons with harder momenta. Two
examples are given: the factorization of soft gluons in B->D pi, and the
soft-collinear convolution for the B->Xs gamma spectrum.Comment: 32 pages, 11 figs, journal versio
Foregrounds for observations of the cosmological 21 cm line: I. First Westerbork measurements of Galactic emission at 150 MHz in a low latitude field
We present the first results from a series of observations conducted with the
Westerbork telescope in the 140--160 MHz range with a 2 arcmin resolution aimed
at characterizing the properties of the foregrounds for epoch of reionization
experiments. For the first time we have detected fluctuations in the Galactic
diffuse emission on scales greater than 13 arcmin at 150 MHz, in the low
Galactic latitude area known as Fan region. Those fluctuations have an of
14 K. The total intensity power spectrum shows a power--law behaviour down to
with slope . The detection of
diffuse emission at smaller angular scales is limited by residual point
sources. We measured an confusion noise of 3 mJy beam.
Diffuse polarized emission was also detected for the first time at this
frequency. The polarized signal shows complex structure both spatially and
along the line of sight. The polarization power spectrum shows a power--law
behaviour down to with slope .
The of polarization fluctuations is 7.2 K on 4 arcmin scales. By
extrapolating the measured spectrum of total intensity emission, we find a
contamination on the cosmological signal of K on 5 arcmin scales and a corresponding value
of 18.3 K at the same angular scale. The level of the polarization power
spectrum is K on 5 arcmin scales. Given its exceptionally
bright polarized signal, the Fan region is likely to represent an upper limit
on the sky brightness at moderate and high Galactic latitude.Comment: Minor corrections made to match the final version printed on A&A. A
version with high resolution figures is available at
http://www.astro.rug.nl/~bernardi/FAN/fan.pd
Lyapunov exponents for products of complex Gaussian random matrices
The exact value of the Lyapunov exponents for the random matrix product with each , where
is a fixed positive definite matrix and a complex Gaussian matrix with entries standard complex normals, are
calculated. Also obtained is an exact expression for the sum of the Lyapunov
exponents in both the complex and real cases, and the Lyapunov exponents for
diffusing complex matrices.Comment: 15 page
D3MOBILE METROLOGY WORLD LEAGUE: TRAINING SECONDARY STUDENTS ON SMARTPHONE-BASED PHOTOGRAMMETRY
The advent of the smartphones brought with them higher processing capabilities and improved camera specifications which boosted the applications of mobile-based imagery in a range of domains. One of them is the 3-D reconstruction of objects by means of photogrammetry, which now enjoys great popularity. This fact brings potential opportunities to develop educational procedures in high schools using smartphone-based 3-D scanning techniques. On this basis, we designed a Project Based e-Learning (PBeL) initiative to introduce secondary students to the disciplines of photogrammetry through the use of their mobile phones in an attractive and challenging way for them. The paper describes the motivation behind the project "D3MOBILE Metrology World League", supported by ISPRS as part of the "Educational and Capacity Building Initiative 2020"programme. With this Science, Technology, Engineering and Mathematics (STEM) initiative, we implement a methodology with the format of an international competition, that can be adapted to daily classwork at the high school level anywhere in the world. Therefore, the championship is essentially structured around a collection of well-thought-out e-learning materials (text guidelines, video tutorials, proposed exercises, etc.), providing a more flexible access to content and instruction at any time and from any place. The methodology allows students to gain spatial skills and to practice other transversal abilities, learn the basics of photogrammetric techniques and workflows, gain experience in the 3-D modelling of simple objects and practice a range of techniques related to the science of measurementS
Antecipação do período de diagnose foliar em laranjeira 'Pêra' no Amazonas.
O objetivo deste trabalho foi avaliar a possibilidade de se antecipar o período de realização da diagnose foliar em laranjeira 'Pêra'. Vinte e sete pomares representativos da região produtora de laranja do Estado do Amazonas foram monitorados durante o ano agrícola de 2011/2012. Foram realizadas diagnoses da composição nutricional (CND) em amostras foliares retiradas durante a floração e quando a árvore apresentava frutos com três e seis meses de idade (época tradicional para o monitoramento nutricional). Pomares com produtividade superior a 25 Mg ha‑1 foram selecionados para o estabelecimento dos padrões de referência. O estado nutricional da laranja variou com o estádio fenológico no qual se realizou a amostragem foliar, o que fez com que fosse necessário estabelecer normas CND para cada período. Com a antecipação da diagnose para o período de floração, observouse aumento nas concentrações foliares de N, P, K e Cu diminuição e nas de Ca. A antecipação da diagnose foliar em laranja 'Pêra' depende da geração de padrões nutricionais CND específicos para cada época de amostragem
Study of the genetic variability in a Parkinson's Disease gene: EIF4G1
Chartier-Harlin and colleagues [2] recently reported mutations in the eukaryotic translation initiation factor 4-gamma (EIF4G1) gene in families with parkinsonism. Large-scale screening found two mutations (p.R1205H and p.A502V) only in affected individuals, although their relative frequency was very low. The aim of this study was to investigate EIF4G1 parkinsonism-related variants in two separate cohorts and study coding variability across the gene. We first screened a series of familial Parkinson's Disease (PD) patients in an attempt to confirm previous results by showing segregation. Then, to determine the extent of coding variation in the gene, we first screened a cohort of sub-Saharan African individuals from the Centre d'Etude du Polymorphisme Humain - Human Genome Diversity Cell Line Panel (HGDP) [1] and then analyzed data from 5350 individuals National Heart, Lung, and Blood Institute (NHLBI) exome sequencing project. We failed to identify any PD-related mutations in the familial samples. Conversely we found the p.A502V variant in the NHLBI population. We observed a high number of coding polymorphism in the exons where the two PD variants have been previously reported. We conclude that either EIF4G1 variants are an extremely rare cause of familial PD in Caucasian cohorts, or that A502V is in fact a rare benign variant not involved in PD aetiology. Our data also suggests that the protein can tolerate some extent of variability particularly at this point of the gene
Investigating the TeV Morphology of MGRO J1908+06 with VERITAS
We report on deep observations of the extended TeV gamma-ray source MGRO
J1908+06 made with the VERITAS very high energy (VHE) gamma-ray observatory.
Previously, the TeV emission has been attributed to the pulsar wind nebula
(PWN) of the Fermi-LAT pulsar PSR J1907+0602. We detect MGRO J1908+06 at a
significance level of 14 standard deviations (14 sigma) and measure a photon
index of 2.20 +/- 0.10_stat +/- 0.20_sys. The TeV emission is extended,
covering the region near PSR J1907+0602 and also extending towards SNR
G40.5--0.5. When fitted with a 2-dimensional Gaussian, the intrinsic extension
has a standard deviation of sigma_src = 0.44 +/- 0.02 degrees. In contrast to
other TeV PWNe of similar age in which the TeV spectrum softens with distance
from the pulsar, the TeV spectrum measured near the pulsar location is
consistent with that measured at a position near the rim of G40.5--0.5, 0.33
degrees away.Comment: To appear in ApJ, 8 page
The BaR-SPOrt Experiment
BaR-SPOrt (Balloon-borne Radiometers for Sky Polarisation Observations) is an
experiment to measure the linearly polarized emission of sky patches at 32 and
90 GHz with sub-degree angular resolution. It is equipped with high sensitivity
correlation polarimeters for simultaneous detection of both the U and Q stokes
parameters of the incident radiation. On-axis telescope is used to observe
angular scales where the expected polarization of the Cosmic Microwave
Background (CMBP) peaks. This project shares most of the know-how and
sophisticated technology developed for the SPOrt experiment onboard the
International Space Station. The payload is designed to flight onboard long
duration stratospheric balloons both in the Northern and Southern hemispheres
where low foreground emission sky patches are accessible. Due to the weakness
of the expected CMBP signal (in the range of microK), much care has been spent
to optimize the instrument design with respect to the systematics generation,
observing time efficiency and long term stability. In this contribution we
present the instrument design, and first tests on some components of the 32 GHz
radiometer.Comment: 12 pages, 10 figures, Astronomical Telescopes and Instrumentation
(Polaimetry in Astronomy) Hawaii August 2002 SPIE Meetin
- …