899 research outputs found
LA CONSTRUCCIÓN DE LA ARQUITECTURA ORGANIZATIVA EN LAS ENTIDADES SIN FINES DE LUCRO. EL CASO DE LAS ONGD EN ESPAÑA
RESUMENEl objetivo del presente trabajo es valorar el equilibrio de las fuerzas organizativas en la construcción de una arquitectura organizativa eficiente y, todo ello, bajo un enfoque de agencia. Los resultados del análisis empírico, llevado a cabo en las más importantes ONGD españolas durante el año 2003, ponen de relieve la gran importancia de la influencia mutua de la delegación de derechos de decisión, sistemas de incentivos y el uso de medidas de evaluación del rendimiento en el logro del equilibrio organizativo, lo que nos permite afirmar que, para el caso estudiado, la teoría se confirma.ABSTRACTThe aim of this paper is to evaluate the balance of organizational components in the design of an efficient organizational architecture from an agency perspective. The results of the empirical analysis, performed in the most prominent Spanish NGDO throughout the year 2003, show the great importance of the mutual influence among the delegation of decision rights, the incentive systems and the use of performance measurements in the achievement of organizational equilibrium
Patrones de actividad y abundancias estacionales del Flamenco Andino (Phoe-nicoparrus andinus) en dos humedales contrastantes en Argentina
El Flamenco Andino utilizade forma complementaria y alternativa humedales altoandinos de Argentina, Bolivia, Chile y Perú,además de humedales en las tierras bajas de Argentina. Estudios previos se enfocaron en su com-portamiento en sitios andinos, pero no existen al momento estudios de este tipo en sitios de tierrasbajas. Debido a esto, el objetivo del estudio fue analizar los patrones de actividad, de despliegues decortejo y abundancias de esta especie de flamenco en dos humedales contrastantes. Los sitios de es-tudio fueron: la Laguna de Vilama, en el noroeste de Argentina y a 4500 m s.n.m., la cual es utilizadaen el verano durante el período reproductivo; y la Laguna Melincué, en la planicie del centro-este deArgentina y a 84 m s.n.m., que es utilizada durante el período no reproductivo invernal. Entre sitios yentre años hubo marcadas diferencias en la abundancia y en los patrones de actividad. En la Lagunade Vilama, los flamencos se alimentaron durante la mayor parte del tiempo (95%), mientras que enla Laguna Melincué, los flamencos mostraron un rango más amplio de comportamientos, destinandosólo el 60% del tiempo a alimentarse. No registramos despliegues nupciales (marchas) en la Lagunade Vilama, mientras que en la Laguna Melincué sí registramos marchas, las cuales fueron másfrecuentes y de mayor duración en aquellos años con mayores abundancias de flamencos. Las dife-rencias en actividades entre los sitios estarían asociadas a la calidad y disponibilidad de recursos yal momento del ciclo reproductivo, donde los sitios de tierras bajas proveen hábitats críticos paralas actividades de cortejo que finalmente influyen el éxito reproductivo en los humedales de los AltosAndes.The Andean Flamingo (Phoenicoparrus andinus), one of three flamingo species in southernSouth America makes complementary and alternative use of high Andean wetlands in Argentina, Bolivia,Chile and Peru, and lowland wetlands in Argentina over its life cycle. Previous studies have focused onits behavior in Andean sites, but there are no such studies in lowland sites. Therefore, we analyzed theactivity patterns, courtship displays, and individual abundance of this flamingo species at two contrastingwetland sites, Laguna de Vilama, located at 4500 m a.s.l. in northwestern Argentina and used in summerduring the breeding season, and Laguna Melincué, a lowland wetland located at 84 m a.s.l. in the plainsof central east Argentina and used in winter during the non-breeding season. There were marked differ-ences in flamingo abundance and activity patterns between sites and years. In Laguna de Vilama, fla-mingos were feeding most of the time (95%), whereas at Laguna Melincué, flamingos showed a broaderrange of behaviors, with only a 60% of time spent feeding. We did not record marching displays atLaguna de Vilama, whereas at Laguna Melincué we recorded marching events in each of the three studyyears, being more frequent and lasting longer in the year with higher flamingo abundance. The differ-ences in behaviors at these sites are associated with resource quality and availability and with timing ofthe reproductive cycle, with lowland wetlands providing critical habitats for courtship displays that influ-ence reproductive success of this species breeding colonies in high Andean wetlands. Accepted 1 Octo-ber 2014Fil: Derlindati, Enrique Javier. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto Geonorte; Argentina. Grupo de Conservación Flamencos Altoandinos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Romano, Marcelo C. Grupo de Conservación Flamencos Altoandinos; Argentina. Centro de Investigaciones en Biodiversidad y Ambiente. Rosario; ArgentinaFil: Cruz, Nancy N.. Grupo de Conservación Flamencos Altoandinos; Argentina. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto Geonorte; ArgentinaFil: Barisón, Caterina. Grupo de Conservación Flamencos Altoandinos; Argentina. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arengo, Felicity. Grupo de Conservación Flamencos Altoandinos; Argentina. American Museum Of Natural History; Estados UnidosFil: Barberis, Ignacio Martín. Grupo de Conservación Flamencos Altoandinos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Spectroscopic characterization of 78 DENIS ultracool dwarf candidates in the solar neighborhood and the Upper Sco OB association
Aims: Low-resolution optical spectroscopic observations for 78 very low-mass
star and brown dwarf candidates that have been photometrically selected using
the DENIS survey point source catalogue. Methods: Spectral types are derived
for them using measurements of the PC3 index. They range from M6 to L4. H_alpha
emission and NaI subordinate doublet (818.3 nm and 819.9 nm) equivalent widths
are measured in the spectra. Spectroscopic indices of TiO, VO, CrH and FeH
molecular features are also reported. Results: A rule-of-thumb criterion to
select young very low-mass objects using the NaI doublet equivalent width is
given. It is used to confirm seven new members of the Upper Sco OB association
and two new members of the R Cr-A star-forming region. Four of our field
objects are also classified as very young, but are not members of any known
nearby young association. The frequency of lower-gravity young objects in our
field ultracool sample is 8.5%. Our results provide the first spectroscopic
classification for 38 ultracool dwarfs in the solar vicinity with
spectrophotometric distances in the range 17 pc to 65 pc (3 of them are new L
dwarfs within 20 pc).Comment: 25 pages, 10 figures, 7 tables, Accepted by A&
Leisure Boating Environmental Footprint: A Study of Leisure Marinas in Palermo
Ports have played a significant role in the touristic development and further economic growth of Italy. It is the country with the highest number of berths among the nations in the Medi- terranean Sea; over time, Italy has created ports with a range of functions. Therefore, it is of vital importance to evaluate the potential pollutants generated from these docks and propose ways to eliminate those problems. A survey that asked about the carbon footprint and the quality of the water in the water footprint calculation was created and distributed to the management of the ma- rinas’ operations. After receiving the completed surveys, the data were analyzed and translated using emission factors into tons of CO2 equivalent. The amount of greenhouse gases generated by the investigated marinas was determined by calculating the carbon and water footprints of five rep- resentative Palermo marinas, and we aimed to better understand how these port-related operations affect the environment. To pinpoint the pollutant sources within the investigated marinas, an orig- inal P-Mapping/Pareto ratio approach was performed as supported by Pareto’s principle. The find- ings indicated that the primary operations of the marina sector are the main sources of pollution. However, a sizable portion of the emissions were also caused by pollution from supporting opera- tions. Based on the study, the origins of CO2 and pollution in marina operations were clarified. The results obtained enable the authors to make recommendations that all recreational boating activities should be closely supervised in order to reduce CO2 emissions and their input in relation to envi- ronmental degradation
GTC Osiris spectroscopic identification of a faint L subdwarf in the UKIRT Infrared Deep Sky Survey
We present the discovery of an L subdwarf in 234 square degrees common to the
UK Infrared Telescope (UKIRT) Infrared Deep Sky Survey Large Area Survey Data
Release 2 and the Sloan Digital Sky Survey Data Release 3. This is the fifth L
subdwarf announced to date, the first one identified in the UKIRT Infrared Deep
Sky Survey, and the faintest known. The blue optical and near-infrared colors
of ULAS J135058.86+081506.8 and its overall spectra energy distribution are
similar to the known mid-L subdwarfs. Low-resolution optical (700-1000 nm)
spectroscopy with the Optical System for Imaging and low Resolution Integrated
Spectroscopy spectrograph on the 10.4 m Gran Telescopio de Canarias reveals
that ULAS J135058.86+081506.8 exhibits a strong KI pressure-broadened line at
770 nm and a red slope longward of 800 nm, features characteristics of L-type
dwarfs. From direct comparison with the four known L subdwarfs, we estimate its
spectral type to be sdL4-sdL6 and derive a distance in the interval 94-170 pc.
We provide a rough estimate of the space density for mid-L subdwarfs of
1.5x10^(-4) pc^(-3).Comment: 5 pages, 1 table, 3 figures, published in ApJ Letters (January 2010
issue
Search for nearby stars among proper motion stars selected by optical-to-infrared photometry. II. Two late M dwarfs within 10 pc
We have identified two late M dwarfs within 10 parsecs of the Sun, by
cross-correlating the Luyten NLTT catalogue of stars with proper motions larger
than 0.18 arcsec/yr, with objects lacking optical identification in the 2MASS
data base. The 2MASS photometry was then combined with improved optical
photometry obtained from the SuperCOSMOS Sky Surveys. The two objects (LP775-31
and LP655-48) have extremely red optical-to-infrared colours ((R-K)~7) and very
bright infrared magnitudes (K_s<10): follow-up optical spectroscopy with the
ESO 3.6-m telescope gave spectral types of M8.0 and M7.5 dwarfs, respectively.
Comparison of their near-infrared magnitudes with the absolute magnitudes of
known M8 and M7.5 dwarfs with measured trigonometric parallaxes yields
spectroscopic distance estimates of 6.4+/-1.4 parsecs and 8.0+/-1.6 parsecs for
LP775-31 and LP655-48, respectively. In contrast, Cruz & Reid (2002) recently
determined spectral types of M6 for both objects, and commensurately larger
distances of 11.3+/-1.3 parsecs and 15.3+/-2.6 parsecs. LP655-48 is also a
bright X-ray source (1RXS J044022.8-053020). With only a few late M dwarfs
previously known within 10 parsecs, these two objects represent an important
addition to the census of the Solar neighbourhood.Comment: Astronomy & Astrophysics (Letters), in press; 5 pages, 1 figure, uses
aa.cls version 5.
Intermediate Resolution Near-Infrared Spectroscopy of 36 late-M Dwarfs
We present observations of 36 late-M dwarfs obtained with the KeckII/NIRSPEC
in the J-band at a resolution of \sim20,000. We have measured projected
rotational velocities, absolute radial velocities, and pseudo-equivalent widths
of atomic lines. 12 of our targets did not have previous measurements in the
literature.
For the other 24 targets, we confirm previously reported measurements. We
find that 13 stars from our sample have vsini below our measurement threshold
(12 km/s) whereas four of our targets are fast rotators (vsini > 30 km/s). As
fast rotation causes spectral features to be washed out, stars with low
projected rotational velocities are sought for radial velocity surveys.
At our intermediate spectral resolution we have confirmed the identification
of neutral atomic lines reported in Mclean et al. 2007. We also calculated
pseudo-equivalent widths (p-EW) of 12 atomic lines. Our results confirm that
the p-EW of K I lines are strongly dependent on spectral types. We observe that
the p-EW of Fe I and Mn I lines remain fairly constant with later spectral
type. We suggest that those lines are particularly suitable for deriving
metallicities for late-M dwarfs.Comment: accepted in Astronomical Journal. 30 pages, 7 tables, and 7 figure
Optical linear polarization in ultra cool dwarfs: A tool to probe dust in the ultra cool dwarf atmospheres
Aims.Recent studies have detected linear polarization in L dwarfs in the
optical I band. Theoretical models have been developed to explain this
polarization. These models predict higher polarization at shorter wavelengths.
We discuss the polarization in the R and I band of 4 ultra cool dwarfs.
Methods.We report linear polarization measurements of 4 ultra cool dwarfs in
the R and I bands using the Intermediate dispersion Spectrograph and Imaging
System (ISIS) mounted on the 4.2m William Herschel Telescope (WHT). Results.As
predicted by theoretical models, we find a higher degree of polarization in the
R band when compared to polarization in the I band for 3/4 of these ultra cool
dwarfs. This suggests that dust scattering asymmetry is caused by oblateness
>.We also show how these measurements fit the theoretical models. A case for
variability of linear polarization is found, which suggests the presence of
randomly distributed dust clouds. We also discuss one case for the presence of
a cold debris disk.Comment: 7 pages, 2 figure
New neighbours: V. 35 DENIS late-M dwarfs between 10 and 30 parsecs
This paper reports updated results on our systematic mining of the DENIS
database for nearby very cool M-dwarfs (M6V-M8V, 2.0<I-J<3.0, photometric
distance within 30 pc), We calibrate the DENIS (M_I, I-J) colour-luminosity
relationship from M dwarfs with well measured parallaxes (HIP, GCTP,...),
obtaining distance errors for single dwarfs of 25%. Using proper motions
measured on archive Schmidt plates for stars that meet the photometric
selection criteria, we eliminate the giants by a Reduced Proper Motion cutoff,
which is significantly more selective than a simple proper motion cutoff.
Here we present new data for 62 red dwarf candidates selected over 5700
square degrees in the DENIS database. 26 of those originate in the 2100 square
degrees analysed in Paper I, with improved parameters here, and 36 were found
in 3600 additional square degrees. 25 of those are new nearby dwarfs. We
determine from that sample of 62 stars a stellar density for 12.0<M_I<14.0 of
2.2(+-0.4)E-3 stars/pc^3/mag. This value is consistent with photometric
luminosity functions measured from deeper and smaller-field observations, but
not with the nearby star luminosity function. In addition we cross-identified
the NLTT and DENIS catalogues to find 15 similar stars, in parts of the sky not
yet covered by the colour-selected search.Comment: Accepted by Astronomy & astrophysics. 17 pages, 8 figure
Follow-up observations of binary ultra-cool dwarfs
Astrometric observations of resolved binaries provide estimates of orbital
periods and will eventually lead to measurement of dynamical masses. Only a few
very low mass star and brown dwarf masses have been measured to date, and the
mass-luminosity relation still needs to be calibrated.
We have monitored 14 very low mass multiple systems for several years to
confirm their multiplicity and, for those with a short period, derive accurate
orbital parameters and dynamical mass estimates.
We have used high spatial resolution images obtained at the Paranal, Lick and
HST observatories to obtain astrometric and photometric measurements of the
multiple systems at several epochs. The targets have periods ranging from 5 to
200 years, and spectral types in the range M7.5 - T5.5.
All of our 14 multiple systems are confirmed as common proper motion pairs.
One system (2MASSW J0920122+351742) is not resolved in our new images, probably
because the discovery images were taken near maximum elongation. Six systems
have periods short enough to allow dynamical mass measurements within the next
15 to 20years. We estimate that only 8% of the ultracool dwarfs in the solar
neighborhood are binaries with separations large enough to be resolved, and yet
periods short enough to derive astrometric orbital fits over a reasonable time
frame with current instrumentation. A survey that doubles the number of
ultracool dwarfs observed with high angular resolution is called for to
discover enough binaries for a first attempt to derive the mass-luminosity
relationship for very low-mass stars and brown dwarfs.Comment: 13 pages, 6 Tables, 4 Figures, Accepted for A&A, reference pb
correcte
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