379 research outputs found
L'Evolució del turisme en espais rurals: un estat de la qüestió
Tourism evolution in rural areas: a state of the art
Rural tourism is born as an activity linked to rural accommodation and farming
practices. Step by step, the tourist practice in rural areas diversified itself and included
specialized culture and nature related activities. Spa users and hikers were the first to
explore the Pyrenees, but it was not until the rise of mass tourism in mountain regions
–skiing–, when suitable zones of the Pyrenees began to develop tourism, too often linked
to economic development excessively and exclusively. Thus, current research deals with
the literature in relation to rural tourism in mountain destinations, its beginnings and its
evolution in the context of the Catalan Pyrenees.La evolución del turismo en espacios rurales: un estado de la
cuestión
El turismo rural nace como una actividad vinculada a los alojamientos rurales y a las
prácticas agrÃcolas y ganaderas. Poco a poco la práctica turÃstica en espacios rurales se irá
diversificando e incluirá turismos especializados relacionados con la cultura y la naturaleza.
La actividad balnearia y los excursionistas fueron los primeros en explorar los Pirineos
catalanes, pero no fue hasta la llegada del turismo de masas a las regiones de montaña,
con el esquÃ, cuando las zonas propicias de los Pirineos empezaron a desarrollar la actividad
turÃstica, en ocasiones vinculada excesiva y exclusivamente al desarrollo económico. AsÃ,
la presenta investigación expone la literatura existente en relación al turismo rural en
destinos de montaña, sus inicios y su evolución en el contexto de los Pirineos de Catalunya.El turisme rural neix com una activitat vinculada als allotjaments rurals i a les prà ctiques
agrÃcoles i ramaderes. A poc a poc la prà ctica turÃstica en espais rurals es va diversificant
i inclou turismes especialitzats relacionats amb la cultura i la naturalesa. L'activitat
balneà ria i els excursionistes van ser els primers a explorar els Pirineus catalans, però no
va ser fins l'arribada del turisme de masses en regions de muntanya, amb l'esquÃ, que les
zones propÃcies dels Pirineus van començar a desenvolupar l'activitat turÃstica, massa
vegades vinculada exclusivament al desenvolupament econòmic. AixÃ, la present recerca
tracta sobre la literatura vinculada el turisme rural en destinacions de muntanya, els seus
inicis i la seva evolució en el context dels Pirineus de Catalunya
Anà lisi d'estabilitat de diferents esllavissaments al Pirineu mitjançant el mètode de l'equilibri lÃmit. Influència del nivell freà tic en les reactivacions
Les pluges són el principal motor de ractivació d'esllavissaments de vessants al Pirineu, podent provocar importants desperfectes. L'objectiu d'aquest treball és reobar quina és la influència dels diferents factors que intervenen en l'estabilitat dels vessants, amb especial atenció al nivell freà tic. Es realitzen assaigs de laboratori per caracteritzar el material del vessant i s'utilitza el Mètode de l'Equilibri LÃmit per estudiar l'estabilitat i les condicions de reactivació d'una sèrie de vessant
Recensions
François DAGOGNET, La maîtrise du vivant
Anà lisi d'estabilitat de diferents esllavissaments al Pirineu mitjançant el mètode de l'equilibri lÃmit. Influència del nivell freà tic en les reactivacions
Les pluges són el principal motor de ractivació d'esllavissaments de vessants al Pirineu, podent provocar importants desperfectes. L'objectiu d'aquest treball és reobar quina és la influència dels diferents factors que intervenen en l'estabilitat dels vessants, amb especial atenció al nivell freà tic. Es realitzen assaigs de laboratori per caracteritzar el material del vessant i s'utilitza el Mètode de l'Equilibri LÃmit per estudiar l'estabilitat i les condicions de reactivació d'una sèrie de vessant
Cost-effectiveness and harm-benefit analyses of risk-based screening strategies for breast cancer
The one-size-fits-all paradigm in organized screening of breast cancer is shifting towards a personalized approach. The
present study has two objectives: 1) To perform an economic evaluation and to assess the harm-benefit ratios of screening
strategies that vary in their intensity and interval ages based on breast cancer risk; and 2) To estimate the gain in terms of
cost and harm reductions using risk-based screening with respect to the usual practice. We used a probabilistic model and
input data from Spanish population registries and screening programs, as well as from clinical studies, to estimate the
benefit, harm, and costs over time of 2,624 screening strategies, uniform or risk-based. We defined four risk groups, low,
moderate-low, moderate-high and high, based on breast density, family history of breast cancer and personal history of
breast biopsy. The risk-based strategies were obtained combining the exam periodicity (annual, biennial, triennial and
quinquennial), the starting ages (40, 45 and 50 years) and the ending ages (69 and 74 years) in the four risk groups.
Incremental cost-effectiveness and harm-benefit ratios were used to select the optimal strategies. Compared to risk-based
strategies, the uniform ones result in a much lower benefit for a specific cost. Reductions close to 10% in costs and higher
than 20% in false-positive results and overdiagnosed cases were obtained for risk-based strategies. Optimal screening is
characterized by quinquennial or triennial periodicities for the low or moderate risk-groups and annual periodicity for the
high-risk group. Risk-based strategies can reduce harm and costs. It is necessary to develop accurate measures of individual
risk and to work on how to implement risk-based screening strategies.This study was funded by grants PS09/01340 and PS09/01153 from the Health Research Fund (Fondo de Investigación Sanitaria) of the Spanish Ministry of Health. The authors thank the Breast Cancer Surveillance Consortium and the funding that the BCSC received from the National Cancer Institute (U01CA63740, U01CA86076, U01CA86082, U01CA63736, U01CA70013, U01CA69976, U01CA63731, U01CA70040, and HHSN261201100031C). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Another look at the BL Lacertae flux and spectral variability
The GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope
(WEBT) monitored BL Lacertae in 2008-2009 at radio, near-IR, and optical
frequencies. During this period, high-energy observations were performed by
XMM-Newton, Swift, and Fermi. We analyse these data with particular attention
to the calibration of Swift UV data, and apply a helical jet model to interpret
the source broad-band variability. The GASP-WEBT observations show an optical
flare in 2008 February-March, and oscillations of several tenths of mag on a
few-day time scale afterwards. The radio flux is only mildly variable. The UV
data from both XMM-Newton and Swift seem to confirm a UV excess that is likely
caused by thermal emission from the accretion disc. The X-ray data from
XMM-Newton indicate a strongly concave spectrum, as well as moderate flux
variability on an hour time scale. The Swift X-ray data reveal fast (interday)
flux changes, not correlated with those observed at lower energies. We compare
the spectral energy distribution (SED) corresponding to the 2008 low-brightness
state, which was characterised by a synchrotron dominance, to the 1997 outburst
state, where the inverse-Compton emission was prevailing. A fit with an
inhomogeneous helical jet model suggests that two synchrotron components are at
work with their self inverse-Compton emission. Most likely, they represent the
radiation from two distinct emitting regions in the jet. We show that the
difference between the source SEDs in 2008 and 1997 can be explained in terms
of pure geometrical variations. The outburst state occurred when the
jet-emitting regions were better aligned with the line of sight, producing an
increase of the Doppler beaming factor. Our analysis demonstrates that the jet
geometry can play an extremely important role in the BL Lacertae flux and
spectral variability.Comment: 12 pages, 10 figures, accepted for publication in A&
Dissecting the long-term emission behaviour of the BL Lac object Mrk 421
We report on long-term multiwavelengthmonitoring of blazar Mrk 421 by the GLAST-AGILE
Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and
Steward Observatory, and by the Swift and Fermi satellites. We study the source behaviour in
the period 2007–2015, characterized by several extreme flares. The ratio between the optical,
X-ray and γ -ray fluxes is very variable. The γ -ray flux variations show a fair correlation with
the optical ones starting from 2012.We analyse spectropolarimetric data and find wavelengthdependence
of the polarization degree (P), which is compatible with the presence of the
host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA).
Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of
the EVPA.We build broad-band spectral energy distributions with simultaneous near-infrared
and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite.
They show strong variability in both flux and X-ray spectral shape and suggest a shift of
the synchrotron peak up to a factor of ∼50 in frequency. The interpretation of the flux and
spectral variability is compatible with jet models including at least two emitting regions that
can change their orientation with respect to the line of sight.http://10.0.4.69/mnras/stx2185Accepted manuscrip
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