1,746 research outputs found
On the Robustness of Multidimensional Counting Poverty Orderings
Counting poverty measures have gained prominence in the analysis of multidimensional poverty in recent decades. Poverty orderings based on these measures typically depend on methodological choices regarding individual poverty functions, poverty cut-offs, and dimensional weights whose impact on poverty rankings is often not well understood. In this paper we propose new dominance conditions that allow the analyst to evaluate the robustness of poverty comparisons to those choices. These conditions provide an approach to evaluating the sensitivity of poverty orderings superior to the common approach of considering a restricted and arbitrary set of indices, cut-offs, and weights. The new criteria apply to a broad class of counting poverty measures widely used in empirical analysis of poverty in developed and developing countries including the multidimensional headcount and the adjusted headcount ratios. We illustrate these methods with an application to time-trends in poverty in Australia and cross-regional poverty in Peru. Our results highlight the potentially large sensitivity of poverty orderings based on counting measures and the importance of evaluating the robustness of results when performing poverty comparisons across time and regions
Measurement of 1323 and 1487 keV resonances in 15N({\alpha}, {\gamma})19F with the recoil separator ERNA
The origin of fluorine is a widely debated issue. Nevertheless, the
^{15}N({\alpha},{\gamma})^{19}F reaction is a common feature among the various
production channels so far proposed. Its reaction rate at relevant temperatures
is determined by a number of narrow resonances together with the DC component
and the tails of the two broad resonances at E_{c.m.} = 1323 and 1487 keV.
Measurement through the direct detection of the 19F recoil ions with the
European Recoil separator for Nuclear Astrophysics (ERNA) were performed. The
reaction was initiated by a 15N beam impinging onto a 4He windowless gas
target. The observed yield of the resonances at Ec.m. = 1323 and 1487 keV is
used to determine their widths in the {\alpha} and {\gamma} channels. We show
that a direct measurement of the cross section of the
^{15}N({\alpha},{\gamma})^{19}F reaction can be successfully obtained with the
Recoil Separator ERNA, and the widths {\Gamma}_{\gamma} and {\Gamma}_{\alpha}
of the two broad resonances have been determined. While a fair agreement is
found with earlier determination of the widths of the 1487 keV resonance, a
significant difference is found for the 1323 keV resonance {\Gamma}_{\alpha} .
The revision of the widths of the two more relevant broad resonances in the
15N({\alpha},{\gamma})19F reaction presented in this work is the first step
toward a more firm determination of the reaction rate. At present, the residual
uncertainty at the temperatures of the ^{19}F stellar nucleosynthesis is
dominated by the uncertainties affecting the Direct Capture component and the
364 keV narrow resonance, both so far investigated only through indirect
experiments.Comment: 8 pages, 11 figures. Accepted for publication in PR
A New Pleiades Member at the Lithium Substellar Boundary
We present the discovery of an object in the Pleiades open cluster, named
Teide 2, with optical and infrared photometry which place it on the cluster
sequence slightly below the expected substellar mass limit. We have obtained
low- and high-resolution spectra that allow us to determine its spectral type
(M6), radial velocity and rotational broadening; and to detect H in
emission and Li I 670.8 nm in absorption. All the observed properties strongly
support the membership of Teide 2 into the Pleiades. This object has an
important role in defining the reappearance of lithium below the substellar
limit in the Pleiades. The age of the Pleiades very low-mass members based on
their luminosities and absence or presence of lithium is constrained to be in
the range 100--120 Myr.Comment: 17 pages, 3 figure
Studies of Vibrational Properties in Ga Stabilized d-Pu by Extended X-ray Absorption Fine Structure
Temperature dependent extended x-ray absorption fine structure (EXAFS)
spectra were measured for a 3.3 at% Ga stabilized Pu alloy over the range T= 20
- 300 K at both the Ga K-edge and the Pu L_III-edge. The temperature dependence
of the pair-distance distribution widths, \sigma(T) was accurately modeled
using a correlated-Debye model for the lattice vibrational properties,
suggesting Debye-like behavior in this material. We obtain pair- specific
correlated-Debye temperatures, \Theta_cD, of 110.7 +/- 1.7 K and 202.6 +/- 3.7
K, for the Pu-Pu and Ga-Pu pairs, respectively. These results represent the
first unambiguous determination of Ga-specific vibrational properties in PuGa
alloys, and indicate the Ga-Pu bonds are significantly stronger than the Pu-Pu
bonds. This effect has important implications for lattice stabilization
mechanisms in these alloys.Comment: 7 pages, 4 figures, Phys. Rev. B in pres
Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment
This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided
Spherical Mexican Hat wavelet: an application to detect non-Gaussianity in the COBE-DMR maps
The spherical Mexican Hat wavelet is introduced in this paper, with the aim
of testing the Gaussianity of the Cosmic Microwave Background temperature
fluctuations. Using the information given by the wavelet coefficients at
several scales, we have performed several statistical tests on the COBE-DMR
maps to search for evidence of non-Gaussianity. Skewness, kurtosis, scale-scale
correlations (for two and three scales) and Kolmogorov-Smirnov tests indicate
that the COBE-DMR data are consistent with a Gaussian distribution. We have
extended the analysis to compare temperature values provided by COBE-DMR data
with distributions (obtained from Gaussian simulations) at each pixel and at
each scale. The number of pixels with temperature values outside the 95% and
the 99% is consistent with that obtained from Gaussian simulations, at all
scales. Moreover, the extrema values for COBE-DMR data (maximum and minimum
temperatures in the map) are also consistent with those obtained from Gaussian
simulations.Comment: to be published in MNRA
Inherited germline T790M mutation and somatic epidermal growth factor receptor mutations in non-small cell lung cancer patients.
Five cases of non-small cell lung cancer, associated with germline transmission of epidermal growth factor receptor (EGFR)-T790M mutation, have been reported1; these patients had family histories of lung cancer. The activity of gefitinib was tested in only two patients, who were both refractory to this drug.2 Herein, we describe a family of European descent in which two family members had non-small cell lung cancer associated with germline transmission of T790M mutation and who were treated with gefitinib
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