5,123 research outputs found
Democratization, Parliamentary Power, and Belligerency: A Quantitative Analysis
Research linking democratization, institutional strength, and war prescribes the construction of strong central government institutions prior to mass elections as a prime mechanism for mitigating the danger of international belligerency associated with democratization. However, institutional analysis of the democratization â war linkage skews institutional strength measures in favour of the executive, overlooking the other arms of government. Drawing on CĂŽte dâIvoireâs 2010 â 2011 internationalized post-election civil conflict, which was largely engendered by excessive executive powers and limited legislative leverage, this paper quantitatively evaluates the effect state legislatures bear on the democratization â war linkage. The evaluations yield at least some evidence for the postulated influence of state legislatures. Thus, whilst heeding extant scholarly recommendations for strengthening state institutions, foreign policies promoting liberal democracy should ensure the ultimate institutional configuration of power in aspirant democracies favours parliaments over executives for more auspicious outcomes
Energy dependence of pion in-medium effects on \pi^-/\pi^+ ratio in heavy-ion collisions
Within the framework of a thermal model with its parameters fitted to the
results from an isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport
model, we study the pion in-medium effect on the charged-pion ratio in
heavy-ion collisions at various energies. We find that due to the cancellation
between the effects from pion-nucleon s-wave and p-wave interactions in nuclear
medium, the \pi^-/\pi^+ ratio generally decreases after including the pion
in-medium effect. The effect is larger at lower collision energies as a result
of narrower pion spectral functions at lower temperatures.Comment: 4 pages, 4 figures, 1 table, minor modifications, version to appear
in Physical Review
Shear viscosity of neutron-rich nucleonic matter near its liquid-gas phase transition
Within a relaxation time approach using free nucleon-nucleon cross sections
modified by the in-medium nucleon masses that are determined from an isospin-
and momentum-dependent effective nucleon-nucleon interaction, we investigate
the specific shear viscosity () of neutron-rich nucleonic matter near
its liquid-gas phase transition. It is found that as the nucleonic matter is
heated at fixed pressure or compressed at fixed temperature, its specific shear
viscosity shows a valley shape in the temperature or density dependence, with
the minimum located at the boundary of the phase transition. Moreover, the
value of drops suddenly at the first-order liquid-gas phase transition
temperature, reaching as low as times the KSS bound of .
However, it varies smoothly for the second-order liquid-gas phase transition.
Effects of the isospin degree of freedom and the nuclear symmetry energy on the
value of are also discussed.Comment: 6 pages, 5 figure
A Span-Extraction Dataset for Chinese Machine Reading Comprehension
Machine Reading Comprehension (MRC) has become enormously popular recently
and has attracted a lot of attention. However, the existing reading
comprehension datasets are mostly in English. In this paper, we introduce a
Span-Extraction dataset for Chinese machine reading comprehension to add
language diversities in this area. The dataset is composed by near 20,000 real
questions annotated on Wikipedia paragraphs by human experts. We also annotated
a challenge set which contains the questions that need comprehensive
understanding and multi-sentence inference throughout the context. We present
several baseline systems as well as anonymous submissions for demonstrating the
difficulties in this dataset. With the release of the dataset, we hosted the
Second Evaluation Workshop on Chinese Machine Reading Comprehension (CMRC
2018). We hope the release of the dataset could further accelerate the Chinese
machine reading comprehension research. Resources are available:
https://github.com/ymcui/cmrc2018Comment: 6 pages, accepted as a conference paper at EMNLP-IJCNLP 2019 (short
paper
Electron energy-loss spectroscopy and ab initio electronic structure of the LaOFeP superconductor
The electronic band structures of the LaOFeP superconductor have been
calculated theoretically by the first principles method and measured
experimentally by electron energy loss spectroscopy. The calculations indicate
that the Fe atom in LaOFeP crystal shows a weak magnetic moment and does not
form a long-range magnetic ordering. Band structure, Fermi surfaces and
fluorine-doping effects are also analyzed based on the data of the density
functional theory. The fine structures of the EELS data have been carefully
examined in both the low loss energy region and the core losses region (O K, Fe
L2,3, and La M4,5). A slight bump edge at 44 eV shows notable
orientation-dependence: it can be observed in the low loss EELS spectra with q
parallel to c, but becomes almost invisible in the q vertical to c spectra.
Annealing experiments indicate that low oxygen pressure favors the appearance
of superconductivity in LaOFeP, this fact is also confirmed by the changes of
Fe L2,3 and O K excitation edges in the experimental EELS data
HSIC Regularized LTSA
Hilbert-Schmidt Independence Criterion (HSIC) measures statistical independence between two random variables. However, instead of measuring the statistical independence between two random variables directly, HSIC first transforms two random variables into two Reproducing Kernel Hilbert Spaces (RKHS) respectively and then measures the kernelled random variables by using Hilbert-Schmidt (HS) operators between the two RKHS. Since HSIC was first proposed around 2005, HSIC has found wide applications in machine learning. In this paper, a HSIC regularized Local Tangent Space Alignment algorithm (HSIC-LTSA) is proposed. LTSA is a well-known dimensionality reduction algorithm for local homeomorphism preservation. In HSIC-LTSA, behind the objective function of LTSA, HSIC between high-dimensional and dimension-reduced data is added as a regularization term. The proposed HSIC-LTSA has two contributions. First, HSIC-LTSA implements local homeomorphism preservation and global statistical correlation during dimensionality reduction. Secondly, HSIC-LTSA proposes a new way to apply HSIC: HSIC is used as a regularization term to be added to other machine learning algorithms. The experimental results presented in this paper show that HSIC-LTSA can achieve better performance than the original LTSA
Nuclear symmetry potential in the relativistic impulse approximation
Using the relativistic impulse approximation with the Love-Franey \textsl{NN}
scattering amplitude developed by Murdock and Horowitz, we investigate the
low-energy (100 MeV MeV) behavior of the nucleon
Dirac optical potential, the Schr\"{o}dinger-equivalent potential, and the
nuclear symmetry potential in isospin asymmetric nuclear matter. We find that
the nuclear symmetry potential at fixed baryon density decreases with
increasing nucleon energy. In particular, the nuclear symmetry potential at
saturation density changes from positive to negative values at nucleon kinetic
energy of about 200 MeV. Furthermore,the obtained energy and density dependence
of the nuclear symmetry potential is consistent with those of the isospin- and
momentum-dependent MDI interaction with , which has been found to describe
reasonably both the isospin diffusion data from heavy-ion collisions and the
empirical neutron-skin thickness of Pb.Comment: 8 pages, 5 figures, revised version to appear in PR
Triplet luminescent dinuclear-gold(I) complex-based light-emitting diodes with low turn-on voltage
The electroluminescence (EL) from a dinuclear-gold(I)-chlorate compound containing bridging phosphine ligands [Au 2(dppm)Cl 2] as emitting layer is reported. Devices with a structure Al/Au 2(dppm)Cl 2/indium-tin-oxide demonstrated a uniform emission under the driving voltage below 1 V. The EL emission was from triplet excited state and the emission color of the device was found to depend on the deposition rate of Au 2(dppm)Cl 2, which can be explained as the different aggregation forms of the stacking compound in the deposition process. © 1999 American Institute of Physics.published_or_final_versio
FusionQ: a novel approach for gene fusion detection and quantification from paired-end RNA-Seq
Background: Gene fusions, which result from abnormal chromosome rearrangements, are a pathogenic factor in cancer development. The emerging RNA-Seq technology enables us to detect gene fusions and profile their features. Results: In this paper, we proposed a novel fusion detection tool, FusionQ, based on paired-end RNA-Seq data. This tool can detect gene fusions, construct the structures of chimerical transcripts, and estimate their abundances. To confirm the read alignment on both sides of a fusion point, we employed a new approach, residual sequence extension , which extended the short segments of the reads by aggregating their overlapping reads. We also proposed a list of filters to control the false-positive rate. In addition, we estimated fusion abundance using the Expectation-Maximization algorithm with sparse optimization, and further adopted it to improve the detection accuracy of the fusion transcripts. Simulation was performed by FusionQ and another two stated-of-art fusion detection tools. FusionQ exceeded the other two in both sensitivity and specificity, especially in low coverage fusion detection. Using paired-end RNA-Seq data from breast cancer cell lines, FusionQ detected both the previously reported and new fusions. FusionQ reported the structures of these fusions and provided their expressions. Some highly expressed fusion genes detected by FusionQ are important biomarkers in breast cancer. The performances of FusionQ on cancel line data still showed better specificity and sensitivity in the comparison with another two tools. Conclusions: FusionQ is a novel tool for fusion detection and quantification based on RNA-Seq data. It has both good specificity and sensitivity performance. FusionQ is free and available at http://www.wakehealth.edu/CTSB/Software/Software.htm
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