2,369 research outputs found
Strong Cosmic Censorship in Charged de Sitter spacetime with Scalar Field Non-minimally Coupled to Curvature
We examine the stability and the strong cosmic censorship in the
Reissner-Nordstrom-de Sitter (RN-dS) black hole by investigating the evolution
of a scalar field non-minimally coupled to the curvature. We find that when the
coupling parameter is negative, the RN-dS black hole experiences instability.
The instability disappears when the coupling parameter becomes non-negative.
With the increase of the coupling parameter, the violation of the strong cosmic
censorship occurs at a larger critical charge ratio. But such an increase of
the critical charge is suppressed by the increase of the cosmological constant.
Different from the minimal coupling situation, it is possible to accommodate
in the near extremal black hole when the scalar field is
non-minimally coupled to curvature. The increase of the cosmological constant
can allow to be satisfied for even smaller value of the coupling
parameter. The existence of implies that the resulting curvature
can continuously cross the Cauchy horizon.Comment: 14 pages, 4 figures, 5 table
Observation of backscattering-immune chiral electromagnetic modes without time reversal breaking
A strategy is proposed to realize robust transport in time reversal invariant
photonic system. Using numerical simulation and microwave experiment, we
demonstrate that a chiral guided mode in the channel of a three-dimensional
dielectric woodpile photonic crystal is immune to the scattering of a square
patch of metal or dielectric inserted to block the channel. The chirality based
robust transport can be realized in nonmagnetic dielectric materials without
any external field.Comment: 16 pages, 5 figure
ElixirNet: Relation-aware Network Architecture Adaptation for Medical Lesion Detection
Most advances in medical lesion detection network are limited to subtle
modification on the conventional detection network designed for natural images.
However, there exists a vast domain gap between medical images and natural
images where the medical image detection often suffers from several
domain-specific challenges, such as high lesion/background similarity, dominant
tiny lesions, and severe class imbalance. Is a hand-crafted detection network
tailored for natural image undoubtedly good enough over a discrepant medical
lesion domain? Is there more powerful operations, filters, and sub-networks
that better fit the medical lesion detection problem to be discovered? In this
paper, we introduce a novel ElixirNet that includes three components: 1)
TruncatedRPN balances positive and negative data for false positive reduction;
2) Auto-lesion Block is automatically customized for medical images to
incorporate relation-aware operations among region proposals, and leads to more
suitable and efficient classification and localization. 3) Relation transfer
module incorporates the semantic relationship and transfers the relevant
contextual information with an interpretable the graph thus alleviates the
problem of lack of annotations for all types of lesions. Experiments on
DeepLesion and Kits19 prove the effectiveness of ElixirNet, achieving
improvement of both sensitivity and precision over FPN with fewer parameters.Comment: 7 pages, 5 figure, AAAI202
Study on Perfume Stimulating Olfaction with Volatile Oil of Acorus Gramineus for Treatment of the Alzheimer's Disease Rat
ObjectiveTo probe into the therapeutic efect of perfume stimulating olfaction with volatile oil of Acorus Gramineus on the Alzheimer's disease (AD) rat.MethodsTotally 50 adult SD rats, male, weighing 300±10 g, were randomly divided into 5 groups, normal group (group A), olfactory nerve severing model group (group B), AD model group (group C), AD model plus perfume stimulation group (group D), AD model olfactory nerve severing plus perfume stimulation group (group E), 10 rats in each group. After perfume stimulation, Morris maze test was conducted for valuating the learning and memory ability; Malondaldehyde (MDA) content, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in the brain, and the brain weight were detected.ResultsCompared with the AD model group, the average escape latency and swimming distance in 6 days were significantly shorter than those in the group A, B, D (P<0.01), with no significant differences between the group C and the group E (P>0.05); Compared with the group A, B and D, MDA content in the group C significantly increased (P<0.01), and SOD and GSH-Px activities significantly decreased (P<0.01), and brain weight/body weight decreased significantly in the group C (P<0.01), with no significant differences between the group C and the group E (P>0.05).ConclusionPerfume stimultating olfaction with volatile oil of Acorus Gramineus can significantly increase the learning-memory ability, decrease MDA content and increase SOD and GSH-Px activities and weight of brain in AD rats
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A Robust Gene Expression Prognostic Signature for Overall Survival in High-Grade Serous Ovarian Cancer.
The objective of this research was to develop a robust gene expression-based prognostic signature and scoring system for predicting overall survival (OS) of patients with high-grade serous ovarian cancer (HGSOC). Transcriptomic data of HGSOC patients were obtained from six independent studies in the NCBI GEO database. Genes significantly deregulated and associated with OS in HGSOCs were selected using GEO2R and Kaplan-Meier analysis with log-rank testing, respectively. Enrichment analysis for biological processes and pathways was performed using Gene Ontology analysis. A resampling/cross-validation method with Cox regression analysis was used to identify a novel gene expression-based signature associated with OS, and a prognostic scoring system was developed and further validated in nine independent HGSOC datasets. We first identified 488 significantly deregulated genes in HGSOC patients, of which 232 were found to be significantly associated with their OS. These genes were significantly enriched for cell cycle division, epithelial cell differentiation, p53 signaling pathway, vasculature development, and other processes. A novel 11-gene prognostic signature was identified and a prognostic scoring system was developed, which robustly predicted OS in HGSOC patients in 100 sampling test sets. The scoring system was further validated successfully in nine additional HGSOC public datasets. In conclusion, our integrative bioinformatics study combining transcriptomic and clinical data established an 11-gene prognostic signature for robust and reproducible prediction of OS in HGSOC patients. This signature could be of clinical value for guiding therapeutic selection and individualized treatment
2,3,4-TrihyÂdroxyÂbenzoic acid 0.25-hydrate
The asymmetric unit of the title compound, C7H6O5·0.25H2O, contains two molÂecules of 2,3,4-trihyÂdroxyÂbenzoic acid, with similar conformations, and one water molÂecule which lies on a twofold rotation axis. Both acid molÂecules are essentially planar [maximum r.m.s deviations = 0.0324 (2) and 0.0542 (3) Å for the two acid molecules]. The molÂecular conformations are stabilized by intraÂmolecular O(phenol)—Hâ‹ŻO(carboxÂyl/phenol) interÂactions. A cyclic interÂmolecular association is formed between the two acid and one water molÂecule [graph set R
3
3(12)] involving O—Hâ‹ŻO hydrogen bonds. The two acid molÂecules are further linked through a cyclic R
2
2(8) carbÂoxyÂlic acid hydrogen-bonding association, which together with interÂmolecular O—Hâ‹ŻO hydrogen-bonding interÂactions involving the phenol groups and the water molÂecule, and weak π–π interÂactions [minimum ring centroid separation = 3.731 (3) Å], give a three-dimensional network
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