4,308 research outputs found
Leptophilic dark matter in gauged model in light of DAMPE cosmic ray excess
Motivated by the very recent cosmic-ray electron+positron excess observed by
DAMPE collaboration, we investigate a Dirac fermion dark matter (DM) in the
gauged model. DM interacts with the electron and muon via the
gauge boson . The model can explain the DAMPE data well.
Although a non-zero DM-nucleon cross section is only generated at one loop
level and there is a partial cancellation between and
couplings, we find that a large portion of mass is ruled out from
direct DM detection limit leaving the allowed mass to be close to two
times of the DM mass. Implications for and , and muon anomaly are also studied.Comment: Discussions added, version accepted by EPJ
Validation of the chinese version of the oral health impact profile for TMDs (OHIP- TMDs-C)
Objectives: The aim of this study was to evaluate the reliability and validity of the the Chinese version of the Oral
Health Impact Profile for TMDs (OHIP-TMDs-C).
Study Design: The OHIP-TMDs was initially translated and cross-culturally adapted to Chinese following international guidelines; then subsequently validated for the psychometric characteristics of reliability and validity. In
total, 156 participants with temporomandibular disorders (TMDs) were recruited to complete the questionnaire.
The reliability of the OHIP-TMDs-C was evaluated using internal consistency and test-retest methods. The validity of the OHIP-TMDs-C was analysed by construct validity and convergent validity. Construct validity was determined based on factor analysis, and convergent validity by analyzing the correlation between OHIP-TMDs-C
subscale scores and the global rating of oral health question.
Results: Cronbach’s alpha value (internal reliability) for the total OHIP-TMDs-C score was 0.917 and the intraclass correlation coefficient (ICC) value (test–retest reliability) was 0.899. Construct validity was determined by
factor analysis, extracting five factors, accounting for 78.6% of the variance. All items had factor loadings above
0.40. In terms of convergent validity, the OHIP-TMDs-C subscale was significant correlated to the global oral
health rating.
Conclusions: The results suggest that the OHIP-TMDs-C has good reliability and validity and thus may be used
as a valuable instrument for patients with TMDs in China
CO J=3-2 Emission from the "Water Fountain" Sources IRAS 16342-3814 and IRAS 18286-0959
We observed CO J=3-2 emission from the "water fountain" sources, which
exhibit high-velocity collimated stellar jets traced by water maser emission,
with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope. We
detected the CO emission from two sources, IRAS 16342-3814 and IRAS 18286-0959.
The IRAS 16342-3814 CO emission exhibits a spectrum that is well fit to a
Gaussian profile, rather than to a parabolic profile, with a velocity width
(FWHM) of 158+/-6 km/s and an intensity peak at VLSR = 50+/-2 km/s. The mass
loss rate of the star is estimated to be ~2.9x10^-5 M_sun/yr. Our
morpho-kinematic models suggest that the CO emission is optically thin and
associated with a bipolar outflow rather than with a (cold and relatively
small) torus. The IRAS 18286-0959 CO emission has a velocity width (FWHM) of
3.0+/-0.2 km/s, smaller than typically seen in AGB envelopes. The narrow
velocity width of the CO emission suggests that it originates from either an
interstellar molecular cloud or a slowly-rotating circumstellar envelope that
harbors the water maser source.Comment: 10 pages, 4 figure, accepted for publication in the Publications of
the Astronomical Society of Japan, Vol. 61, No.6, 2009 December issu
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Soft phototactic swimmer based on self-sustained hydrogel oscillator.
Oscillations are widely found in living organisms to generate propulsion-based locomotion often driven by constant ambient conditions, such as phototactic movements. Such environment-powered and environment-directed locomotions may advance fully autonomous remotely steered robots. However, most man-made oscillations require nonconstant energy input and cannot perform environment-dictated movement. Here, we report a self-sustained soft oscillator that exhibits perpetual and untethered locomotion as a phototactic soft swimming robot, remotely fueled and steered by constant visible light. This particular out-of-equilibrium actuation arises from a self-shadowing-enabled negative feedback loop inherent in the dynamic light-material interactions, promoted by the fast and substantial volume change of the photoresponsive hydrogel. Our analytical model and governing equation unveil the oscillation mechanism and design principle with key parameters identified to tune the dynamics. On this autonomous oscillator platform, we establish a broadly applicable principle for converting a continuous input into a discontinuous output. The modular design can be customized to accommodate various forms of input energy and to generate diverse oscillatory behaviors. The hydrogel oscillator showcases agile life-like omnidirectional motion in the entire three-dimensional space with near-infinite degrees of freedom. The large force generated by the powerful and long-lasting oscillation can sufficiently overcome water damping and effectively self-propel away from a light source. Such a hydrogel oscillator-based all-soft swimming robot, named OsciBot, demonstrated high-speed and controllable phototactic locomotion. This autonomous robot is battery free, deployable, scalable, and integratable. Artificial phototaxis opens broad opportunities in maneuverable marine automated systems, miniaturized transportation, and solar sails
Information Geometry Theoretic Measures for Characterizing Neural Information Processing from Simulated EEG Signals
In this work, we explore information geometry theoretic measures for characterizing neural information processing from EEG signals simulated by stochastic nonlinear coupled oscillator models for both healthy subjects and Alzheimer’s disease (AD) patients with both eyes-closed and eyes-open conditions. In particular, we employ information rates to quantify the time evolution of probability density functions of simulated EEG signals, and employ causal information rates to quantify one signal’s instantaneous influence on another signal’s information rate. These two measures help us find significant and interesting distinctions between healthy subjects and AD patients when they open or close their eyes. These distinctions may be further related to differences in neural information processing activities of the corresponding brain regions, and to differences in connectivities among these brain regions. Our results show that information rate and causal information rate are superior to their more traditional or established information-theoretic counterparts, i.e., differential entropy and transfer entropy, respectively. Since these novel, information geometry theoretic measures can be applied to experimental EEG signals in a model-free manner, and they are capable of quantifying non-stationary time-varying effects, nonlinearity, and non-Gaussian stochasticity presented in real-world EEG signals, we believe that they can form an important and powerful tool-set for both understanding neural information processing in the brain and the diagnosis of neurological disorders, such as Alzheimer’s disease as presented in this work
Systematic investigation of the rotational bands in nuclei with using a particle-number conserving method based on a cranked shell model
The rotational bands in nuclei with are investigated
systematically by using a cranked shell model (CSM) with the pairing
correlations treated by a particle-number conserving (PNC) method, in which the
blocking effects are taken into account exactly. By fitting the experimental
single-particle spectra in these nuclei, a new set of Nilsson parameters
( and ) and deformation parameters ( and
) are proposed. The experimental kinematic moments of inertia
for the rotational bands in even-even, odd- and odd-odd nuclei, and the
bandhead energies of the 1-quasiparticle bands in odd- nuclei, are
reproduced quite well by the PNC-CSM calculations. By analyzing the
-dependence of the occupation probability of each cranked Nilsson
orbital near the Fermi surface and the contributions of valence orbitals in
each major shell to the angular momentum alignment, the upbending mechanism in
this region is understood clearly.Comment: 21 pages, 24 figures, extended version of arXiv: 1101.3607 (Phys.
Rev. C83, 011304R); added refs.; added Fig. 4 and discussions; Phys. Rev. C,
in pres
Plant diversity of Southeast Asia-II
The special issue of plant diversity in Southeast Asia will focus on the documentation of new discoveries in SE Asia. There are four global biodiversity hotspots in Southeast Asia. Although there are many plans to protect this rich biodiversity, however, the rich biodiversity in SE Asia is under threat due to economic development and population growth. There is a huge gap between our knowledge and biodiversity in SE Asia. During the last six investigations, many new taxa, including new species, new genera, have been discovered. This special issue will bring the rich but little known biodiversity to the public and protect them
Energy Spectrum Theory of Incommensurate Systems
Due to the lack of the translational symmetry, calculating the energy
spectrum of an incommensurate system has always been a theoretical challenge.
Here, we propose a natural approach to generalize the energy band theory to the
incommensurate systems without reliance on the commensurate approximation, thus
providing a comprehensive energy spectrum theory of the incommensurate systems.
Except for a truncation dependent weighting factor, the formulae of this theory
are formally almost identical to that of the Bloch electrons, making it
particularly suitable for complex incommensurate structures. To illustrate the
application of this theory, we give three typical examples: one-dimensional
bichromatic and trichromatic incommensurate potential model, as well as a
moir\'{e} quasicrystal. Our theory establishes a fundamental framework for
understanding the incommensurate systems.Comment: 7 pages, 3 figure
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