26,448 research outputs found
Revealing spatio-spectral electroencephalographic dynamics of musical mode and tempo perception by independent component analysis.
BackgroundMusic conveys emotion by manipulating musical structures, particularly musical mode- and tempo-impact. The neural correlates of musical mode and tempo perception revealed by electroencephalography (EEG) have not been adequately addressed in the literature.MethodThis study used independent component analysis (ICA) to systematically assess spatio-spectral EEG dynamics associated with the changes of musical mode and tempo.ResultsEmpirical results showed that music with major mode augmented delta-band activity over the right sensorimotor cortex, suppressed theta activity over the superior parietal cortex, and moderately suppressed beta activity over the medial frontal cortex, compared to minor-mode music, whereas fast-tempo music engaged significant alpha suppression over the right sensorimotor cortex.ConclusionThe resultant EEG brain sources were comparable with previous studies obtained by other neuroimaging modalities, such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET). In conjunction with advanced dry and mobile EEG technology, the EEG results might facilitate the translation from laboratory-oriented research to real-life applications for music therapy, training and entertainment in naturalistic environments
Experimental Two-dimensional Quantum Walk on a Photonic Chip
Quantum walks, in virtue of the coherent superposition and quantum
interference, possess exponential superiority over its classical counterpart in
applications of quantum searching and quantum simulation. The quantum enhanced
power is highly related to the state space of quantum walks, which can be
expanded by enlarging the photon number and/or the dimensions of the evolution
network, but the former is considerably challenging due to probabilistic
generation of single photons and multiplicative loss. Here we demonstrate a
two-dimensional continuous-time quantum walk by using the external geometry of
photonic waveguide arrays, rather than the inner degree of freedoms of photons.
Using femtosecond laser direct writing, we construct a large-scale
three-dimensional structure which forms a two-dimensional lattice with up to
49X49 nodes on a photonic chip. We demonstrate spatial two-dimensional quantum
walks using heralded single photons and single-photon-level imaging. We analyze
the quantum transport properties via observing the ballistic evolution pattern
and the variance profile, which agree well with simulation results. We further
reveal the transient nature that is the unique feature for quantum walks of
beyond one dimension. An architecture that allows a walk to freely evolve in
all directions and a large scale, combining with defect and disorder control,
may bring up powerful and versatile quantum walk machines for classically
intractable problems.Comment: 7 pages, 4 figures. The experiment has been performed again with
heralded single photons instead of the coherent ligh
Non-classical photon correlation in a two-dimensional photonic lattice
Quantum interference and quantum correlation, as two main features of quantum
optics, play an essential role in quantum information applications, such as
multi-particle quantum walk and boson sampling. While many experimental
demonstrations have been done in one-dimensional waveguide arrays, it remains
unexplored in higher dimensions due to tight requirement of manipulating and
detecting photons in large-scale. Here, we experimentally observe non-classical
correlation of two identical photons in a fully coupled two-dimensional
structure, i.e. photonic lattice manufactured by three-dimensional femtosecond
laser writing. Photon interference consists of 36 Hong-Ou-Mandel interference
and 9 bunching. The overlap between measured and simulated distribution is up
to . Clear photon correlation is observed in the two-dimensional
photonic lattice. Combining with controllably engineered disorder, our results
open new perspectives towards large-scale implementation of quantum simulation
on integrated photonic chips.Comment: 10 pages, 5 figure
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Effect of Blood Pressure Control on Long-Term Risk of End-Stage Renal Disease and Death Among Subgroups of Patients With Chronic Kidney Disease.
Background Our objective was to explore the effect of intensive blood pressure (BP) control on kidney and death outcomes among subgroups of patients with chronic kidney disease divided by baseline proteinuria, glomerular filtration rate, age, and body mass index. Methods and Results We included 840 MDRD (Modification of Diet in Renal Disease) trial and 1067 AASK (African American Study of Kidney Disease and Hypertension) participants. We used Cox models to examine whether the association between intensive BP control and risk of end-stage renal disease (ESRD) or death is modified by baseline proteinuria (≥0.44 versus <0.44 g/g), glomerular filtration rate (≥30 versus <30 mL/min per 1.73 m2), age (≥40 versus <40 years), or body mass index (≥30 versus <30 kg/m2). The median follow-up was 14.9 years. Strict (versus usual) BP control was protective against ESRD (hazard ratio [HR]ESRD, 0.77; 95% CI, 0.64-0.92) among those with proteinuria ≥0.44 g/g but not proteinuria <0.44 g/g. Strict (versus usual) BP control was protective against death (HRdeath, 0.73; 95% CI, 0.59-0.92) among those with glomerular filtration rate <30 mL/min per 1.73 m2 but not glomerular filtration rate ≥30 mL/min per 1.73 m2 (HRdeath, 0.98; 95% CI, 0.84-1.15). Strict (versus usual) BP control was protective against ESRD among those ≥40 years (HRESRD, 0.82; 95% CI, 0.71-0.94) but not <40 years. Strict (versus usual) BP control was also protective against ESRD among those with body mass index ≥30 kg/m2 (HRESRD, 0.75; 95% CI, 0.61-0.92) but not body mass index <30 kg/m2. Conclusions The ESRD and all-cause mortality benefits of intensive BP lowering may not be uniform across all subgroups of patients with chronic kidney disease. But intensive BP lowering was not associated with increased risk of ESRD or death among any subgroups that we examined
A Magnetohydrodynamic Model for the Formation of Episodic Jets
Episodic ejection of plasma blobs have been observed in many black hole
systems. While steady, continuous jets are believed to be associated with
large-scale open magnetic fields, what causes the episodic ejection of blobs
remains unclear. Here by analogy with the coronal mass ejection on the Sun, we
propose a magnetohydrodynamical model for episodic ejections from black holes
associated with the closed magnetic fields in an accretion flow. Shear and
turbulence of the accretion flow deform the field and result in the formation
of a flux rope in the disk corona. Energy and helicity are accumulated and
stored until a threshold is reached. The system then loses its equilibrium and
the flux rope is thrust outward by the magnetic compression force in a
catastrophic way. Our calculations show that for parameters appropriate for the
black hole in our Galactic center, the plasmoid can attain relativistic speeds
in about 35 minutes.Comment: 8 pages, 2 figures; the finalized version to appear in MNRA
Clinicopathological features and CCT2 and PDIA2 expression in gallbladder squamous/adenosquamous carcinoma and gallbladder adenocarcinoma
BACKGROUND: Gallbladder cancer (GBC) is a relatively uncommon carcinoma among gastrointestinal cancers and usually has a rather poor prognosis. The most common subtype of GBC is adenocarcinoma (AC), which accounts for about 90% of GBC. Squamous carcinoma/adenosquamous carcinoma (SC/ASC) are comparatively rare histopathological subtypes of GBC. The clinicopathological features and biological behaviors of SC/ASC have not been well-characterized. No molecular biomarkers are currently available for predicting the progression, metastasis, and prognosis of the SC/ASC subtype of GBC. METHODS: We examined the expression levels of CCT2 and PDIA3 by immunohistochemistry (IHC) staining in human GBC tissue samples collected from 46 patients with SC/ASC and evaluated the clinicopathological significance of both CCT2 and PDIA3 expression in the SC/ASC subtypes of GBC by Kaplan-Meier analysis and multivariate Cox regression analysis. For comparison, we included specimens from 80 AC patients in our study to investigate the specificity of CCT2 and PDIA3 expression in GBC subtypes. RESULTS: We found that the positive expression of CCT2 and PDIA3 was significantly associated with clinicopathological features of both SC/ASC and AC specimens, including high TNM stage and lymph node metastasis. Univariate analysis revealed that the two-year survival rate was significantly lower for patients with positive expression of CCT2 and PDIA3 than for those with negative expression. Multivariate analysis also indicated that the positive expression of CCT2 and PDIA3 was negatively correlated with poor postoperative patient survival and positively correlated with high mortality. CONCLUSIONS: Our study suggests that positive expression of CCT2 or PDIA3 is associated with tumor progression and the clinical behavior of gallbladder carcinoma. Therefore, CCT2 and PDIA3 could be potentially important diagnostic and prognostic biomarkers for both SC/ASC and AC subtypes of GBC
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