5,058 research outputs found
Spectropolarimetric analysis of an active region filament. I. Magnetic and dynamical properties from single component inversions
The determination of the magnetic filed vector in solar filaments is possible
by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral
lines like those of the He I multiplet at 10830 A. We study the vector magnetic
field of an active region filament (NOAA 12087). Spectropolarimetric data of
this active region was acquired with the GRIS instrument at the GREGOR
telescope and studied simultaneously in the chromosphere with the He I 10830 A
multiplet and in the photosphere with the Si I 10827 A line. As it is usual
from previous studies, only a single component model is used to infer the
magnetic properties of the filament. The results are put into a solar context
with the help of the Solar Dynamic Observatory images. Some results clearly
point out that a more complex inversion had to be done. Firstly, the Stokes
map of He I does not show any clear signature of the presence of the filament.
Secondly, the local azimuth map follows the same pattern than Stokes as if
the polarity of Stokes were conditioning the inference to very different
magnetic field even with similar linear polarization signals. This indication
suggests that the Stokes could be dominated by the below magnetic field
coming from the active region, and not, from the filament itself. Those and
more evidences will be analyzed in depth and a more complex inversion will be
attempted in the second part of this series.Comment: 18 pages, 19 figures, accepted for publication in A&
Estudios sobre las Rubiáceas de México, XLIX
Abstract
The new Arachnothryx species collected in Veracruz is a vicarious one of the next related Arachnothryx secundiflora (B. L. Rob.) Borhidi of Oaxaca, Tabasco and Chiapas, which differs in having sessile bractless cymes. Another closely related species A. linguiloba Borhidi et Diego Pérez of Guerrero differs in size and pubescence of stipules and leaves and the size and shape of the flowers. This paper presents also a short note about the generic delimitation of Arachnothryx Planch. 1849 not Lorence 2012
Variability in grape composition and phenology of 'Tempranillo' in zones located at different elevations and with differences in the climatic conditions
The objective of this research was to analyse the variability on phenology and berry composition of 'Tempranillo' among different elevations and different climatic conditions. The study was conducted on 'Tempranillo' vineyards located in Rioja DOCa at elevations between 367 and 650 m a.s.l. Phenology and the evolution of berry composition during ripening, related to pH, total acidity, malic acid, total anthocyanins, total polyphenols index, colour intensity and sugar content were analysed for the period 2008-2018 at each elevation. The weather conditions recorded during the period of study were evaluated.
The results indicate that, on average, differences between the analysed elevations of up to 21 days existed in the dates in which the maturity was reached, being the differences higher in the years with extreme conditions (very wet or dry and very hot or cool). The comparative analysis among elevations and in years with differences in temperature and in precipitation allowed knowing the differences in the vine response under different climatic conditions. From this analysis some conclusions may be extracted that may be useful for police makers to define new planting areas in which less imbalanced situations may occur under warm conditions
Interannual and spatial variability of grape composition in the Rioja DOCa show better resilience of cv. graciano than cv. tempranillo under a warming scenario
Weather conditions affect vine development and grape composition, although the response may be different depending
on the variety and altitude. Under scenarios of climate change, the knowledge of the relationships between grape
composition and climate is therefore important to know the suitability of a given cultivar. In this research, the
variability of the grape composition of two red varieties with different phenological timings (Vitis vinifera L. cv.
Tempranillo and Graciano) cultivated in Rioja DOCa (Spain) and the climatic variables that have a higher effect on the
response of each of them were analysed. Grape composition of both cultivars at technical maturity (considered when
a probable volumetric alcoholic degree (PVAD) = 13 º was reached) was analysed during the period 2008–2020 in
areas located at different elevations and related to the weather conditions recorded in those areas. The results show the
effect of temperature and water availability in different periods during the growing cycle on grape composition and the
potential benefits of cultivating at a higher elevation, under higher water availability. The anthocyanins were affected
by the maximum temperatures recorded in the period before veraison and during ripening (period veraison to technical
maturity), decreasing their concentrations with increasing temperatures. In addition, higher water availability gave
rise to an increase in acidity. Graciano is shown as a variety more suitable than Tempranillo to be cultivated under
warmer conditions
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