97,566 research outputs found
Correlation of the earth's rotation rate and the secular change of the geomagnetic field
Power spectral density analysis using Burg's maximum entropy method was applied to the geomagnetic dipole field and its rate of change for the years 1901 to 1969. Both spectra indicate relative maxima at 0.015 cycles/year and its harmonics. These maxima correspond approximately to 66, 33, 22, 17, 13, 11, and 9-year spectral lines. The application of the same analysis techniques to the length-of-day (l.o.d) fluctuations for the period 1865 to 1961 reveal similar spectral characteristics. Although peaks were observed at higher harmonics of the fundamental frequency, the 22-year and 11-year lines are not attributed unambiguously to the solar magnetic cycle and the solar cycle. It is suggested that the similarity in the l.o.d fluctuations and the dipole field variations is related to the motion within the earth's fluid core during the past one hundred years
A flexible mandatory access control policy for XML databases
A flexible mandatory access control policy (MAC) for XML
databases is presented in this paper. The label type and label
access policy can be defined according to the requirements of
applications. In order to preserve the integrity of data in XML
databases, a constraint between a read access rule and a write
access rule in label access policy is introduced. Rules for label
assignment and propagation are proposed to alleviate the
workload of label assignment. Also, a solution for resolving
conflicts of label assignments is proposed. At last, operations for
implementation of the MAC policy in a XML database are
illustrated
Behavior of Complex Knots in Single DNA Molecules
We used optical tweezers to tie individual DNA molecules in knots. Although these knots become highly localized under tension, they remain surprisingly mobile and undergo thermal diffusion with classical random walk statistics. The diffusion constants of knots with different complexities correlate with theoretical calculations of knot sizes. We show that this correlation can be explained by a simple hydrodynamical model of "self-reptation" of the knot along a polymer
Relationship between spin squeezing and single-particle coherence in two-component Bose-Einstein condensates with Josephson coupling
We investigate spin squeezing of a two-mode boson system with a Josephson
coupling. An exact relation between the squeezing and the single-particle
coherence at the maximal-squeezing time is discovered, which provides a more
direct way to measure the squeezing by readout the coherence in atomic
interference experiments. We prove explicitly that the strongest squeezing is
along the axis, indicating the appearance of atom number-squeezed state.
Power laws of the strongest squeezing and the optimal coupling with particle
number are obtained based upon a wide range of numerical simulations.Comment: 4 figures, revtex4, new refs. are adde
Probing higher spin black holes from CFT
In a class of 2D CFTs with higher spin symmetry, we compute thermal two-point
functions of certain scalar primary operators in the presence of nonzero
chemical potential for higher spin charge. These are shown to agree with the
same quantity calculated holographically using scalar fields propagating in a
charged black hole background of 3D higher spin gravity. This match serves as
further evidence for the duality between W_N minimal models at large central
charge and 3D higher spin gravity. It also supports a recent prescription for
computing boundary correlators of multi-trace scalar primary operators in
higher spin theories.Comment: 34 pages, 1 figur
INTEGRATE-Neo: A pipeline for personalized gene fusion neoantigen discovery
Abstract
Motivation
While high-throughput sequencing (HTS) has been used successfully to discover tumor-specific mutant peptides (neoantigens) from somatic missense mutations, the field currently lacks a method for identifying which gene fusions may generate neoantigens.
Results
We demonstrate the application of our gene fusion neoantigen discovery pipeline, called INTEGRATE-Neo, by identifying gene fusions in prostate cancers that may produce neoantigens.
Availability and Implementation
INTEGRATE-Neo is implemented in C ++ and Python. Full source code and installation instructions are freely available from https://github.com/ChrisMaherLab/INTEGRATE-Neo.
Supplementary information
Supplementary data are available at Bioinformatics online.
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Transparency and International Investor Behavior
Does country transparency affect international portfolio investment? We examine this and related questions using some new measures of transparency and a unique micro dataset on international portfolio holdings. We distinguish between government and corporate transparency. There is clear evidence that international funds invest systematically less in less transparent countries. On the other hand, herding among funds tends to be more prevalent in less transparent countries. There is also some evidence that during crises, funds flee non-transparent countries by a greater amount.
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