314 research outputs found
Physicochemical behavior of Riesling x Silvaner grapevine fruit under the high altitude conditions of Colombia (South America)
The Valle del Sol (Sun Valley) of the Boyacá department is a zone with temperate tropical climate conditions (2,500 m above sea level) that is suitable for the production of grapes for quality wine. The objective of this investigation was to study the physical and chemical behavior during growth and development of the grapevine fruit var. Riesling x Silvaner, produced for winemaking, in the municipality of Corrales (Boyacá, Colombia). To determine the physical and chemical characteristics of the fruit starting at 28 days after anthesis (daa), 14 weekly samplings were carried out, in each of which three clusters were taken from randomly selected plants. The development of the berry lasted 119 daa in which three stages were defi ned: herbaceous, veraison and maturation1. The herbaceous stage ended at 63 daa, the veraison period lasted 14 days and ended at 77 daa, whereas the maturation and ripening stage lasted 42 days; no period of overmaturity was observed. The behavior of the fresh mass, dry mass and diameter of the fruit followed a double sigmoid curve. During berry development, total soluble solids (from 5.03 to 23.73 °Brix at the harvest point), pH (from 2.88 to 3.71) and technological maturity index (from 2.27 to 21.84) all increased, whereas total titratable acidity decreased from 3.96 to 1.11%
Strength distribution of solar magnetic fields in photospheric quiet Sun regions
The magnetic topology of the solar photosphere in its quietest regions is
hidden by the difficulties to disentangle magnetic flux through the resolution
element from the field strength of unresolved structures. The observation of
spectral lines with strong coupling with hyperfine structure, like the observed
MnI line at 553.7 nm, allows such differentiation.
The main aim is to analyse the distribution of field strengths in the network
and intranetwork of the solar photosphere through inversion of the MnI line at
553.7 nm.
An inversion code for the magnetic field using the Principal Component
Analysis (PCA) has been developed. Statistical tests are run on the code to
validate it. The code has to draw information from the small-amplitude spectral
feature oppearing in the core of the Stokes V profile of the observed line for
field strengths below a certain threshold, coinciding with lower limit of the
Paschen-Back effect in the fine structure of the involved atomic levels.
The inversion of the observed profiles, using the circular polarization (V)
and the intensity (I), shows the presence of magnetic fields strengths in a
range from 0 to 2 kG, with predominant weak strength values. Mixed regions with
mean strength field values of 1130 and 435 Gauss are found associated with the
network and intranetwork respectively.
The MnI line at 553 nm probes the field strength distribution in the quiet
sun and shows the predominance of weak, hectoGauss fields in the intranetwork,
and strong, kiloGauss fields in the network. It also shows that both network
and intranetwork are to be understood at our present spatial resolutions as
field distributions of which we hint the mean properties.Comment: 10 pages, 6 figure
Efectos del acotamiento al pastoreo en pastizales de montaña de la Sierra del Segura (Albacete)
Fencing influence on overgrazed ranges of the Sierra del Segura is studied, over two fenced plots, during three years. An important increment of cover in herbaceous plants of elevated pastoral value, mainly perennial legumes, is observated. Uncovered soil ratio decreased by effect of fencing. Woody species of elevated pastoral value increment their cover. An important increment in floral richness and diversity is produced during the first year after fencing. Appearance species ratio decreased after the first year.Se estudia la influencia del acotamiento al pastoreo en pastizales esquilmados de la Sierra del Segura sobre dos parcelas acotadas y muestreadas tres años post-acotamiento. Se observa un importante incremento de cobertura en especies herbáceas de interés pastoral, principalmente de leguminosas vivaces, así como de la cobertura de suelo recubierto de vegetación. Las leñosas incrementan ligeramente su cobertura apareciendo diversas especies de interés pastoral. Se produce un importante incremento en la riqueza y diversidad florísticas durante el primer año post-acotamiento, ralentizándose posteriormente la tasa de aparición de especies
Comercialización de cerveza en Asia
El proyecto PAP elaborado para Cervezutra tuvo como propósito realizar una investigación de mercado internacional en donde el principal interés fue posicionar el producto en Asía para dar a conocer la cerveza artesanal del amor.
En este documento se encuentran datos de la empresa en general, descripción del producto, así como el proceso de su fabricación, la fracción arancelaria de la cerveza, el mercado meta y la comercialización de este; la logística donde se abordan temas como empaque, transporte, documentación, regulaciones arancelarias y no arancelarias y las recomendaciones del equipo hacia el empresario. Se presentan también los métodos de investigación que se utilizaron para poder llevar a cabo esta investigación con el fin de brindar una buena asesoría e informar al empresario para que obtenga una idea clara sobre la exportación de su producto al mercado asiático. Este documento final servirá como guía para la exportación a dichos mercados, además tener una visión general de cómo está el panorama en cuestión de cerveza y cerveza artesanal, saber sus gustos e intereses y conocer si el procducto es atractivo en los países de China, Malasia, Taiwán y Japón.ITESO, A.C
Synthesis and Properties of 2′-Deoxy-2′,4′-difluoroarabinose-Modified Nucleic Acids
We report the synthesis, thermal stability, and RNase H substrate activity of 2′-deoxy-2′,4′-difluoroarabino-modified nucleic acids. 2′-Deoxy-2′,4′-difluoroarabinouridine (2,′4′-diF-araU) was prepared in a stereoselective way in six steps from 2′-deoxy-2′-fluoroarabinouridine (2′-F-araU). NMR analysis and quantum mechanical calculations at the nucleoside level reveal that introduction of 4′-fluorine introduces a strong bias toward the North conformation, despite the presence of the 2′-βF, which generally steers the sugar pucker toward the South/East conformation. Incorporation of the novel monomer into DNA results on a neutral to slightly stabilizing thermal effect on DNA-RNA hybrids. Insertion of 2′,4′-diF-araU nucleotides in the DNA strand of a DNA-RNA hybrid decreases the rate of both human and HIV reverse transcriptase-associated RNase H-mediated cleavage of the complement RNA strand compared to that for an all-DNA strand or a DNA strand containing the corresponding 2′-F-araU nucleotide units, consistent with the notion that a 4′-fluorine in 2′-F-araU switches the preferred sugar conformation from DNA-like (South/East) to RNA-like (North)
A rain and scintillation Ka-band channel simulator
This paper describes the implementation of a
Ka-band satellite channel simulator with emphasis on the
synthesis of scintillation processes. The problem becomes
one of generating a given probability density function, the
Moulsley-Vilar distribution, with a specified power spectral
density using aWiener model based on orthogonal Hermite
polynomials for the nonlinearity. A numerical procedure is
devised to calculate the filter and non-linearity coefficients
of the Wiener model. The generation of rain processes
conforms to the Maseng-Bakken model.Postprint (published version
The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data
The use of IFS is since recently allowing to measure the emission line fluxes
of an increasingly large number of star-forming galaxies both locally and at
high redshift. The main goal of this study is to review the most widely used
empirical oxygen calibrations, O3N2 and N2, by using new direct abundance
measurements. We pay special attention to the expected uncertainty of these
calibrations as a function of the index value or abundance derived and the
presence of possible systematic offsets. This is possible thanks to the
analysis of the most ambitious compilation of Te-based HII regions to date.
This new dataset compiles the Te-based abundances of 603 HII regions extracted
from the literature but also includes new measurements from the CALIFA survey.
Besides providing new and improved empirical calibrations for the gas
abundance, we also present here a comparison between our revisited calibrations
with a total of 3423 additional CALIFA HII complexes with abundances derived
using the ONS calibration by Pilyugin et al. (2010). The combined analysis of
Te-based and ONS abundances allows us to derive their most accurate calibration
to date for both the O3N2 and N2 single-ratio indicators, in terms of all
statistical significance, quality and coverage of the space of parameters. In
particular, we infer that these indicators show shallower abundance
dependencies and statistically-significant offsets compared to those of Pettini
and Pagel (2004), Nagao et al. (2006) and P\'erez-Montero and Contini (2009).
The O3N2 and N2 indicators can be empirically applied to derive oxygen
abundances calibrations from either direct abundance determinations with random
errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a
large amount of data) reaching an average precision of 0.08 and 0.09 dex
(random) and 0.02 and 0.08 dex (systematic; compared to the direct
estimations),respectively.Comment: 12 pages, 5 figures, accepted for publication in A&
The second flight of the SUNRISE balloon-borne solar observatory: overview of instrument updates, the flight, the data and first results
The SUNRISE balloon-borne solar observatory, consisting of a 1~m aperture
telescope that provided a stabilized image to a UV filter imager and an imaging
vector polarimeter, carried out its second science flight in June 2013. It
provided observations of parts of active regions at high spatial resolution,
including the first high-resolution images in the Mg~{\sc ii}~k line. The
obtained data are of very high quality, with the best UV images reaching the
diffraction limit of the telescope at 3000~\AA\ after Multi-Frame Blind
Deconvolution reconstruction accounting for phase-diversity information. Here a
brief update is given of the instruments and the data reduction techniques,
which includes an inversion of the polarimetric data. Mainly those aspects that
evolved compared with the first flight are described. A tabular overview of the
observations is given. In addition, an example time series of a part of the
emerging active region NOAA AR~11768 observed relatively close to disk centre
is described and discussed in some detail. The observations cover the pores in
the trailing polarity of the active region, as well as the polarity inversion
line where flux emergence was ongoing and a small flare-like brightening
occurred in the course of the time series. The pores are found to contain
magnetic field strengths ranging up to 2500~G and, while large pores are
clearly darker and cooler than the quiet Sun in all layers of the photosphere,
the temperature and brightness of small pores approach or even exceed those of
the quiet Sun in the upper photosphere.Comment: Accepted for publication in The Astrophysical Journa
Effect of iron addition on the crystal structure of the α-AlFeMnSi phase formed in the quaternary Al-Fe-Mn-Si system
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