19,454 research outputs found
When “conservation” leads to land degradation: lessons from Ban Lak Sip, Laos
Land degradation / Soil erosion / Farming systems / Environmental policy / Political ecology / Households / Population growth / Laos / Ban Lak Sip
Recommended from our members
Coherent modeling of mortality patterns for age-specific subgroups
The recent actuarial literature has shown that mortality patterns and trajectories in closely related populations are similar in some respects and that small differences are unlikely to increase in the long run. The common feeling is that mortality forecasts for individual countries could be improved by taking into account the patterns from a larger group. Starting from this consideration, we apply the three-way Lee–Carter model to a group of countries, by extending the bilinear LC model to a three-way structure, which incorporates a further component in the decomposition of the log-mortality rates. From a methodological point of view, there are several issues to deal with when focusing on such kind of data. In the presence of a three-way data structure, several choices on the pretreatment of the data could affect the whole modeling process. This kind of analysis is useful to assess the source of variation in the raw mortality data, before the extraction of the rank-one components by the LC model. The proposed procedure is used to extract an ad hoc time mortality trend parameter for age-specific subgroups. The results show that the proposed strategy leads to a more coherent description of mortality for age-specific subgroups
Studying the coincidence excess between EXPLORER and NAUTILUS during 1998
The coincidences between EXPLORER and NAUTILUS during 1998 (Astone et al.
2001) are more deeply studied. It is found that the coincidence excess is
greater in the ten-day period 7-17 September 1998 and it occurs at the sidereal
hour 4, when the detectors axes are perpendicular to the Galactic Disk. The
purpose of this paper is to bring our results with the GW detectors to the
attention of scientists working in the astrophysical field, and ask them
whether are they aware of any special phenomenon occurring when EXPLORER and
NAUTILUS showed a coincidence excess.Comment: 5 pages, 7 figures, submitted to A &
Universality and the QCD Anderson Transition
We study the Anderson-type transition previously found in the spectrum of the
QCD quark Dirac operator in the high temperature, quark-gluon plasma phase.
Using finite size scaling for the unfolded level spacing distribution, we show
that in the thermodynamic limit there is a genuine mobility edge, where the
spectral statistics changes from Poisson to Wigner-Dyson statistics in a
non-analytic way. We determine the correlation length critical exponent, ,
and find that it is compatible with that of the unitary Anderson model.Comment: 4 pages, 5 figure
Benign epithelial lesions of the cervix, which can be mistaken as epithelial neoplastic malignancies: Morphological and immunohistochemical analysis
In this paper the Author describes the morphological and the immunohistochemical features of the most common lesions of the cervix, which can be mistaken for neoplastic malignancies (pseudoneoplastic lesions), on microscopic examination.The lesions discussed in this paper represent physiological changes and benign reactive lesions that are the consequences of hormone stimulation or inflammation, which occur in the cervix.
In the cervix there are many lesions which can mimic epithelial malignancies adn here the Author demonstrates that morphological, clinical data and immunohistochemical features are all useful for an accurate differential pathological diagnosi
Electron trapping at point defects on hydroxylated silica surfaces
The origin of electron trapping and negative charging of hydroxylated silica surfaces is predicted based on accurate quantum-mechanical calculations. The calculated electron affinities of the two dominant neutral paramagnetic defects, the nonbridging oxygen center, equivalent to Si-O-center dot, and the silicon dangling bond, equivalent to Si-center dot, demonstrate that both defects are deep electron traps and can form the corresponding negatively charged defects. We predict the structure and optical absorption energies of these diamagnetic defects
- …