6,989 research outputs found
The privatisation of communal lands in spain (1750-1925): an econometric revision of the Neo-Malthusian thesis
The main aim of this paper is to check one of the few existing theories regarding the factors that can explain the historical dissolution of collective rustic property, namely the Neo-Malthusian thesis which underlies the so-called “tragedy of the commons”. This old interpretative proposal, originating in the field of Biology, but rapidly adopted by Economy, not only continues to be explicitly present in some manuals of natural resources management, but also persists in those works that, from Economic and Social History, attempt to understand the reasons of the decline of communal systems in the Western world. Leaving aside the revision that, in the last decades, New Institutional Economy has advanced in this respect through the “property rights theory”, which is difficult to contrast, my paper tries to test the applicability of the Neo-Malthusian schema with the help of elementary econometric methods. The testing ground chosen for this purpose is the process of disintegration of communal lands which took place in Spain since the middle of the 18th century and, especially, the process of privatisation promoted by the Law of General Disentitlement of 1 May 1855. In no way does this analysis attempt to create a refined econometric model with which to explain the changes in collective patrimony during the last centuries. The inclusion in the test of other factors, different from the ones emphasised in the “tragedy of the commons”, suggests and advances some possible approaches to assemble an alternative theoretical schema, but does not endeavour to offer a global mechanical explanation.tragedy of the commons, Neo-Malthusian thesis, privatisation process, collective rustic patrimony, Spain, Extremadura, econometric methods
Wetland restoration and nitrate reduction: the example of the periurban wetland of Vitoria-Gasteiz (Basque Country, North Spain)
Changes in land use and agricultural intensification caused wetlands on the quaternary aquifer of Vitoria-Gasteiz (Basque Country) to disappear some years ago and nitrate concentration in groundwaters increased very quickly. The Basque Government recently declared the East Sector of this aquifer a Vulnerable Zone according to the 91/676/CEE European Directive. Recently, the wetlands have been restored through the closure of the main drainage ditches, the consequent elevation of the water table and the abondonment of agricultural practices near the wetlands. This is the case of the Zurbano wetland. Restoration has allowed the recovery of its biogeochemical function, which has reduced nitrate concentrations in waters. Nitrate concentrations which exceed 50 mg l–1 in groundwaters entering into the wetland are less than 10 mg l–1 at the outlet. Conditions in the wetland are conducive to the loss of nitrates: organic matter rich wetted soils, clay presence allowing a local semiconfined flow and very low hydraulic gradient. Water quality monitoring at several points around the wetland showed the processes involved in nitrate loss, although some aspects still remain unresolved. However, during storm events, the wetland effectively reduces the nitrate concentration entering the Alegria River, the most important river on the quaternary aquifer
Properties of the redback millisecond pulsar binary 3FGL J0212.1+5320
Linares et al. (2016) obtained quasi-simultaneous g', r' and i-band light
curves and an absorption line radial velocity curve of the secondary star in
the redback system 3FGL J0212.1+5320. The light curves showed two maxima and
minima primarily due to the secondary star's ellipsoidal modulation, but with
unequal maxima and minima. We fit these light curves and radial velocities with
our X-ray binary model including either a dark solar-type star spot or a hot
spot due to off-centre heating from an intrabinary shock, to account for the
unequal maxima. Both models give a radial velocity semi-amplitude and
rotational broadening that agree with the observations. The observed secondary
star's effective temperature is best matched with the value obtained using the
hot spot model, which gives a neutron star and secondary star mass of =1.85 and =0.50
, respectively.Comment: 10 pages, 8 figues, accepted by MNRA
Timing the accretion flow around accreting millisecond pulsars
At present, ten years after they were first discovered, ten accreting
millisecond pulsars are known. I present a study of the aperiodic X-ray
variability in three of these systems, which led to the discovery of
simultaneous kHz quasi periodic oscillations in XTE J1807-294 and extremely
strong broadband noise at unusually low variability frequencies in IGR
J00291+5934. Furthermore, we classified SWIFT J1756.9-2508 as an atoll source
and measured in its 2007 outburst spectral and variability properties typical
of the extreme island state. I also give detailed estimates of the total
fluence during the studied outbursts.Comment: To be published in the proceedings of the workshop 'A Decade of
Accreting Millisecond X-ray pulsars' (Amsterdam 14-18 April 2008; Eds.
Wijnands et al.
The identification of MAXI J1659-152 as a black hole candidate
We report on the analysis of all 65 pointed Rossi X-ray Timing Explorer
observations of the recently discovered soft X-ray transient MAXI J1659-152
(initially referred to as GRB 100925A). The source was studied in terms of its
evolution through the hardness-intensity diagram (HID) as well as its X-ray
variability properties. MAXI J1659-152 traced out an anti-clockwise loop in the
HID, which is commonly seen in transient low-mass X-ray binaries. The
variability properties of the source, in particular the detection of type-B and
type-C low-frequency quasi-periodic oscillations, and the way they evolve along
the HID track, indicate that MAXI J1659-152 is a black hole candidate. The
spectral and variability properties of MAXI J1659-152 imply that the source was
observed in the hard and soft intermediate states during the RXTE observations,
with several transitions between these two states.Comment: 6 pages, 4 figures, accepted for publication in ApJ
Live Demonstration: Multiplexing AER Asynchronous Channels over LVDS Links with Flow-Control and Clock- Correction for Scalable Neuromorphic Systems
In this live demonstration we exploit the use of a
serial link for fast asynchronous communication in massively
parallel processing platforms connected to a DVS for realtime
implementation of bio-inspired vision processing on
spiking neural networks
Low-frequency QPO from the 11 Hz accreting pulsar in Terzan 5: not frame dragging
We report on 6 RXTE observations taken during the 2010 outburst of the 11 Hz
accreting pulsar IGR J17480-2446 located in the globular cluster Terzan 5.
During these observations we find power spectra which resemble those seen in
Z-type high-luminosity neutron star low-mass X-ray binaries, with a
quasi-periodic oscillation (QPO) in the 35-50 Hz range simultaneous with a kHz
QPO and broad band noise. Using well known frequency-frequency correlations, we
identify the 35-50 Hz QPOs as the horizontal branch oscillations (HBO), which
were previously suggested to be due to Lense-Thirring precession. As IGR
J17480-2446 spins more than an order of magnitude more slowly than any of the
other neutron stars where these QPOs were found, this QPO can not be explained
by frame dragging. By extension, this casts doubt on the Lense-Thirring
precession model for other low-frequency QPOs in neutron-star and perhaps even
black-hole systems.Comment: 6 pages, 5 figures, Accepted for publication in ApJ
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