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Functional interpretation of single cell similarity maps.
We present Vision, a tool for annotating the sources of variation in single cell RNA-seq data in an automated and scalable manner. Vision operates directly on the manifold of cell-cell similarity and employs a flexible annotation approach that can operate either with or without preconceived stratification of the cells into groups or along a continuum. We demonstrate the utility of Vision in several case studies and show that it can derive important sources of cellular variation and link them to experimental meta-data even with relatively homogeneous sets of cells. Vision produces an interactive, low latency and feature rich web-based report that can be easily shared among researchers, thus facilitating data dissemination and collaboration
Large Merger Recoils and Spin Flips From Generic Black-Hole Binaries
We report the first results from evolutions of a generic black-hole binary,
i.e. a binary containing unequal mass black holes with misaligned spins. Our
configuration, which has a mass ratio of 2:1, consists of an initially
non-spinning hole orbiting a larger, rapidly spinning hole (specific spin a/m =
0.885), with the spin direction oriented -45 degrees with respect to the
orbital plane. We track the inspiral and merger for ~2 orbits and find that the
remnant receives a substantial kick of 454 km/s, more than twice as large as
the maximum kick from non-spinning binaries. The remnant spin direction is
flipped by 103 degrees with respect to the initial spin direction of the larger
hole. We performed a second run with anti-aligned spins, a/m = +-0.5 lying in
the orbital plane that produces a kick of 1830 km/s off the orbital plane. This
value scales to nearly 4000 km/s for maximally spinning holes. Such a large
recoil velocity opens the possibility that a merged binary can be ejected even
from the nucleus of a massive host galaxy.Comment: 4 pages. Accepted for publication in ApJ
Sub-Riemannian Fast Marching in SE(2)
We propose a Fast Marching based implementation for computing sub-Riemanninan
(SR) geodesics in the roto-translation group SE(2), with a metric depending on
a cost induced by the image data. The key ingredient is a Riemannian
approximation of the SR-metric. Then, a state of the art Fast Marching solver
that is able to deal with extreme anisotropies is used to compute a SR-distance
map as the solution of a corresponding eikonal equation. Subsequent
backtracking on the distance map gives the geodesics. To validate the method,
we consider the uniform cost case in which exact formulas for SR-geodesics are
known and we show remarkable accuracy of the numerically computed SR-spheres.
We also show a dramatic decrease in computational time with respect to a
previous PDE-based iterative approach. Regarding image analysis applications,
we show the potential of considering these data adaptive geodesics for a fully
automated retinal vessel tree segmentation.Comment: CIARP 201
Relating leptogenesis parameters to light neutrino masses
We obtain model independent relations among neutrino masses and leptogenesis
parameters. We find exact relations that involve the CP asymmetries
, the washout parameters and
, and the neutrino masses and , as well
as powerful inequalities that involve just and . We
prove that the Yukawa interactions of at least two of the heavy singlet
neutrinos are in the strong washout region ().Comment: 5 pages, 1 figur
Study of Conformally Flat Initial Data for Highly Spinning Black Holes and their Early Evolutions
We study conformally-flat initial data for an arbitrary number of spinning
black holes with exact analytic solutions to the momentum constraints
constructed from a linear combination of the classical Bowen-York and conformal
Kerr extrinsic curvatures. The solution leading to the largest intrinsic spin,
relative to the ADM mass of the spacetime epsilon_S=S/M^2_{ADM}, is a
superposition with relative weights of Lambda=0.783 for conformal Kerr and
(1-Lambda)=0.217 for Bowen-York. In addition, we measure the spin relative to
the initial horizon mass M_{H_0}, and find that the quantity chi=S/M_{H_0}^2
reaches a maximum of \chi^{max}=0.9856 for Lambda=0.753. After equilibration,
the final black-hole spin should lie in the interval 0.9324<chi_{final}<0.9856.
We perform full numerical evolutions to compute the energy radiated and the
final horizon mass and spin. We find that the black hole settles to a final
spin of chi_{final}^{max}=0.935 when Lambda=0.783. We also study the evolution
of the apparent horizon structure of this "maximal" black hole in detail.Comment: 9 pages, 8 figure
Pengaruh Rehidrasi Dengan Minuman Isotonik Terhadap Waktu Reaksi (Studi Perbandingan Dengan Air Mineral)
Background: Reaction time is one of many physiological parameters which has an important role in daily activity. Being dehydrated by just 1-2% body mass loss impairs performance and reduces reaction time. Adequate rehydration is often suggested to prevent severe dehydration. One of many rehydration efforts is by consuming sports drinks.Aim: To investigate the effect of rehydration with sports drinks on reaction time.Methods: This research was true experimental study using 31 students of medical faculty Diponegoro University (22 men and 9 women) between the ages of 18 and 24 as research subjects. Their reaction time were measured by Attentional Network Test (ANT) before dehydration, after dehydration and after rehydration. Subjects were randomly assigned to one of three rehydration groups: sports drinks, mineral water and without rehydration. The methodology to induce dehydration is a total of 5 km of running within 45 minutes.Results: Friedman test was observed there is mean reaction time reduction on subjects with sports drink rehydration (p=0,002). Significant difference in mean reaction time on subjects with sports drinks rehydration was noted at before dehydrated condition to after rehydrated condition (p=0,005). Meanwhile, there is no significant difference in mean reaction time between after dehydrated condition and after rehydrated condition on subjects with sports drinks rehydration (p=0,059). Kruskal-Wallis test showed no significant differences in mean reaction time after rehydration among three groups: sports drinks, mineral water and without rehydration (p=0,593).Conclusions: There was no significant reaction time difference before and after rehydration with sports drinks or mineral water
Volatility of Linear and Nonlinear Time Series
Previous studies indicate that nonlinear properties of Gaussian time series
with long-range correlations, , can be detected and quantified by studying
the correlations in the magnitude series , i.e., the ``volatility''.
However, the origin for this empirical observation still remains unclear, and
the exact relation between the correlations in and the correlations in
is still unknown. Here we find analytical relations between the scaling
exponent of linear series and its magnitude series . Moreover, we
find that nonlinear time series exhibit stronger (or the same) correlations in
the magnitude time series compared to linear time series with the same
two-point correlations. Based on these results we propose a simple model that
generates multifractal time series by explicitly inserting long range
correlations in the magnitude series; the nonlinear multifractal time series is
generated by multiplying a long-range correlated time series (that represents
the magnitude series) with uncorrelated time series [that represents the sign
series ]. Our results of magnitude series correlations may help to
identify linear and nonlinear processes in experimental records.Comment: 7 pages, 5 figure
Overview study on challenges of additive manufacturing for a healthcare application
Additive manufacturing is a rapidly evolving manufacturing technology bringing numerous and wide opportunities for the design team involved in the process by creating intricate and customized products with saving labor, time, and other expenses. Innovative AM methods and numerous practical applications in aerospace, automotive, medical, energy, and other industries have been developed and commercialized through extensive research over the last two decades. One embraced industry among others that benefited from the advances of AM is the healthcare industry. This paper focuses on addressing the challenges and opportunities in Additive manufacturing for healthcare. Although there are advanced possibilities in AM, there are also numerous issues needed to be overcome. The paper is based upon the current state-of-the-art review and study visits. The purpose of this work has been to identify the opportunities and limitations associated with additive manufacturing in healthcare applications and to highlight the identified research needs
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