618 research outputs found
Paclobutrazol effects on cacao seedlings
O efeito do paclobutrazol (2RS, 3RS)-1-(4-Clorofenil) - 4,4-dimefil - 2 - (1H, 2,4 - triazol -1-it) - pentan-3-ol), ICI PP333 nas características morfológicas de plântulas de cacau (Theobroma cacao L.) foi avaliado sob condições de casa de vegetação. O delineamento experimental utilizado foi o inteiramente casualizado com cinco tratamentos e dez repetições. O experimento consistiu na aplicação de 0, 5, 15,45, e 90 ppm de PP333 em plântulas de cacau "Catongo" de 5 meses de idade crescendo em sacos de polietileno com 5 kg de solo. A altura da planta foi o parâmetro mais afetado pela ação do PP333. As maiores dosagens reduziram a altura em 32% em relação ao tratamento testemunha. A dosagem de 15 ppm reduziu o crescimento em 17% e a de 5 ppm não diferiu estatisticamente do controle. A exceção de 90 ppm, que reduziu significativamente o diâmetro do caule em 15%, não se verificaram diferenças significativas nos outros tratamentos em relação a testemunha. A área de cada folha, nas duas maiores dosagens, foi significativamente menor em relação aos tratamentos 0, 5 e 15 ppm. As dosagens maiores decresceram, aproximadamente, 25% a área das folhas. A dosagem de 90 ppm diminuiu o peso da matéria seca total em 21% em relação ao controle. Os pesos da matéria seca da raiz, caule e folhas a 90 ppm foram 32%, 27% e 22% menores, respectivamente, em relação às mesmas partes das plântulas testemunha. A dosagem maior do produto modificou a partição dinâmica de assimilados, decrescendo a razão peso seco da matéria seca da raiz/peso seco da malária seca parte aérea, que foi significativamente menor em relação aos outros tratamentos.The effects of paclobutrazol (2RS, 3RS) -1-(4-Chlorophenyl) - 4,4-dimethyl-2-(1H, 2, 4-triazol- 1 -yl)-pentan-3-ol), ICI PP333 on the morphological characteristics of cacao (Theobroma cacao L.) seedlings were evaluated under greenhouse conditions. The experimental design was a complete randomized design with five treatments and 10 replications. Applications of 5, 15, 45, and 90 ppm of PP333 were made directly to the soil in which 5-months old 'Catongo' cacao seedlings were grown in 5,0 kg poliethylene bags. Plant height was the parameter more affected by the action of PP333. The height reduction by the highest rates was 32% with respect to control plants. The 15 ppm application reduced height by 17% and the 5 ppm did not statistically differ from the control. With the exception of the 90 ppm treatment which significantly reduced stem diameter, the other treatments were not statistically different from the control. Individual leaf area, in the two higher doses, was significantly lower than the control, 0,5, and 15 ppm treatments, by approximately 28%. Total dry weight of plants al the highest rate of PP333 were 21% lower than the control seedlings. Root, stem, and leaf dry weight for the 90 ppm seedlings were 32, 17 and 22% lower than control plants, respectively. The highest dose changed the partitioning of photosynthates, decreasing the root/shoot ratio which was significantly lower
Parisoschoenus obesulus Casey (Coleoptera: Curculionidae) não é praga de frutos novos do coqueiro
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Development and bloom in hybrids of wild passion fruit cultivated in different types of pots and shading levels
Large-scale and multipolar anisotropies of cosmic rays detected at the Pierre Auger Observatory with energies above 4 EeV
Studies of the mass composition of cosmic rays and proton-proton interaction cross-sections at ultra-high energies with the Pierre Auger Observatory
In this work, we present an estimate of the cosmic-ray mass composition from the distributions of the depth of the shower maximum (Xmax) measured by the fluorescence detector of the Pierre Auger Observatory. We discuss the sensitivity of the mass composition measurements to the uncertainties in the properties of the hadronic interactions, particularly in the predictions of the particle interaction cross-sections. For this purpose, we adjust the fractions of cosmic-ray mass groups to fit the data with Xmax distributions from air shower simulations. We modify the proton-proton cross-sections at ultra-high energies, and the corresponding air shower simulations with rescaled nucleus-air cross-sections are obtained via Glauber theory. We compare the energy-dependent composition of ultra-high-energy cosmic rays obtained for the different extrapolations of the proton-proton cross-sections from low-energy accelerator data
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