3,190 research outputs found
Charge-impurity-induced Majorana fermions in topological superconductors
We study numerically Majorana fermions (MFs) induced by a charged impurity in
topological superconductors. It is revealed from the relevant Bogoliubov-de
Gennes equations that (i) for quasi-one dimensional systems, a pair of MFs are
bounded at the two sides of one charge impurity and well separated; and (ii)
for a two dimensional square lattice, the charged-impurity-induced MFs are
similar to the known pair of vortex-induced MFs, in which one MF is bounded by
the impurity while the other appears at the boundary. Moreover, the
corresponding local density of states is explored, demonstrating that the
presence of MF states may be tested experimentally.Comment: 5 pages, 5 figure
Evaluating Summary Statistics with Mutual Information for Cosmological Inference
The ability to compress observational data and accurately estimate physical
parameters relies heavily on informative summary statistics. In this paper, we
introduce the use of mutual information (MI) as a means of evaluating the
quality of summary statistics in inference tasks. MI can assess the sufficiency
of summaries, and provide a quantitative basis for comparison. We propose to
estimate MI using the Barber-Agakov lower bound and normalizing flow based
variational distributions. To demonstrate the effectiveness of our method, we
compare three different summary statistics (namely the power spectrum,
bispectrum, and scattering transform) in the context of inferring reionization
parameters from mock images of 21~cm observations with Square Kilometre Array.
We find that this approach is able to correctly assess the informativeness of
different summary statistics and allows us to select the optimal set of
statistics for inference tasks.Comment: Accepted at the ICML 2023 Workshop on Machine Learning for
Astrophysics, comments welcom
GraMMaR: Ground-aware Motion Model for 3D Human Motion Reconstruction
Demystifying complex human-ground interactions is essential for accurate and
realistic 3D human motion reconstruction from RGB videos, as it ensures
consistency between the humans and the ground plane. Prior methods have modeled
human-ground interactions either implicitly or in a sparse manner, often
resulting in unrealistic and incorrect motions when faced with noise and
uncertainty. In contrast, our approach explicitly represents these interactions
in a dense and continuous manner. To this end, we propose a novel Ground-aware
Motion Model for 3D Human Motion Reconstruction, named GraMMaR, which jointly
learns the distribution of transitions in both pose and interaction between
every joint and ground plane at each time step of a motion sequence. It is
trained to explicitly promote consistency between the motion and distance
change towards the ground. After training, we establish a joint optimization
strategy that utilizes GraMMaR as a dual-prior, regularizing the optimization
towards the space of plausible ground-aware motions. This leads to realistic
and coherent motion reconstruction, irrespective of the assumed or learned
ground plane. Through extensive evaluation on the AMASS and AIST++ datasets,
our model demonstrates good generalization and discriminating abilities in
challenging cases including complex and ambiguous human-ground interactions.
The code will be available at https://github.com/xymsh/GraMMaR.Comment: Accepted to ACM Multimedia 2023. The code will be available at
https://github.com/xymsh/GraMMa
A preliminary study on the key factors contributing to the attractive lips of Chinese children
AbstractObjectiveTo explore the aesthetic characteristics of the Chinese children lips.MethodsFrontal and profile photographs of 653 healthy children were categorized as the attractive and the unattractive by three laypersons and objectively measured for comparison.ResultsThe attractive group tended to be smaller in the upper paramedian red lip height, the lower paramedian red lip height, the midline upper red lip height, the central bow angle, and the lip angle, while greater in the Cupid's bow width.ConclusionsThinner lips seemed to be more attractive than full ones among Chinese children
Inhibition of MDM2 homodimerization by XIAP IRES stabilizes MDM2, influencing cancer cell survival
Chaos-assisted two-octave-spanning microcombs
Since its invention, optical frequency comb has revolutionized a broad range of subjects from metrology to spectroscopy. The recent development of microresonator-based frequency combs (microcombs) provides a unique pathway to create frequency comb systems on a chip. Indeed, microcomb-based spectroscopy, ranging, optical synthesizer, telecommunications and astronomical calibrations have been reported recently. Critical to many of the integrated comb systems is the broad coverage of comb spectra. Here, microcombs of more than two-octave span (450 nm to 2,008 nm) is demonstrated through χ^((2)) and χ^((3)) nonlinearities in a deformed silica microcavity. The deformation lifts the circular symmetry and creates chaotic tunneling channels that enable broadband collection of intracavity emission with a single waveguide. Our demonstration introduces a new degree of freedom, cavity deformation, to the microcomb studies, and our microcomb spectral range is useful for applications in optical clock, astronomical calibration and biological imaging
No association between XRCC1 gene Arg194Trp polymorphism and risk of lung cancer: evidence based on an updated cumulative meta-analysis
X-ray repair cross-complementing group 1 (XRCC1) gene Arg194Trp polymorphism has been reported to be associated with risk of lung cancer in many published studies. Nevertheless, the research results were inconclusive and conflicting. To reach conclusive results, several meta-analysis studies were conducted by combining results from literature reports through pooling analysis. However, these previous meta-analysis studies were still not consistent. Hence, we used an updated and cumulative meta-analysis to get a more comprehensive and precise result from 25 case–control studies searching through the PubMed database up to September 1, 2013. The meta-analysis was carried out by the Comprehensive Meta-Analysis software and the odds ratio (OR) with 95 % confidence interval (CI) was used to estimate the pooled effect. The result involving 8,876 lung cancer patients and 11,210 controls revealed that XRCC1 Arg194Trp polymorphism was not associated with lung cancer risk [(OR = 0.97, 95 %CI = 0.92–1.03) for Trp vs. Arg; (OR = 0.92, 95 % CI = 0.85–0.98) for ArgTrp vs. ArgArg; (OR = 1.07, 95 % CI = 0.92–1.23) for TrpTrp vs. ArgArg; (OR = 0.93, 95 % CI = 0.87–1.00) for (TrpTrp + ArgTrp) vs. ArgArg; and (OR = 1.08, 95 % CI = 0.94–1.25) for TrpTrp vs. (ArgTrp + ArgArg)]. The cumulative meta-analysis showed that the results maintained the same, while the ORs with 95 % CI were more stable with the accumulation of case–control studies. The sensitivity and subgroups analyses showed that the results were robust and not affected by any single study with no publication bias. Relevant studies might not be needed for supporting these results
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