392 research outputs found
Extraction-condition Optimization of Baicalein and Schisandrin from Hu-gan-kang-yuan Formula Using Orthogonal Array Design
Purpose: To optimize the extraction conditions for Hu-gan-kang-yuan Formula based on extraction rates of baicalein and schisandrin using an orthogonal array design.Methods: Ethanol concentration (50 - 70 %), ratio of solvent to raw material (8 - 12 mL/g), and extraction time (1 - 3 h) were examined with a three-factor and three-level L9(3)3 orthogonal array design. In addition, analysis of variance (ANOVA) was used to evaluate the statistical significance of the effects of individual factors on extraction rates of baicalein and schisandrin determined by high performance liquid chromatography (HPLC). The number of extractions was further investigated to confirm the extraction rate of target compounds based on the optimized conditions.Results: The optimized conditions were an ethanol concentration of 70 %; ratio of solvent to raw material, 12:1 mL/g; and extraction time of 60 min. Ethanol concentration and ratio of solvent to raw material showed significant effects on the extraction of the two compounds (p < 0.05). The number of extraction steps, two, was reasonable. The final optimum extraction conditions resulted in 79.48 ± 1.40 and 88.55 ± 1.85 % of extraction for baicalein and schisandrin, respectively.Conclusion: The optimized extraction conditions for baicalein and schisandrin are practicable and repeatable, and can be upgraded for pilot-scale production of Hu-gan-kang-yuan preparations.Keywords: Hu-gan-kang-yuan Formula, Extract-condition optimization, Orthogonal array design, Baicalein, Schisandri
MEDOE: A Multi-Expert Decoder and Output Ensemble Framework for Long-tailed Semantic Segmentation
Long-tailed distribution of semantic categories, which has been often ignored
in conventional methods, causes unsatisfactory performance in semantic
segmentation on tail categories. In this paper, we focus on the problem of
long-tailed semantic segmentation. Although some long-tailed recognition
methods (e.g., re-sampling/re-weighting) have been proposed in other problems,
they can probably compromise crucial contextual information and are thus hardly
adaptable to the problem of long-tailed semantic segmentation. To address this
issue, we propose MEDOE, a novel framework for long-tailed semantic
segmentation via contextual information ensemble-and-grouping. The proposed
two-sage framework comprises a multi-expert decoder (MED) and a multi-expert
output ensemble (MOE). Specifically, the MED includes several "experts". Based
on the pixel frequency distribution, each expert takes the dataset masked
according to the specific categories as input and generates contextual
information self-adaptively for classification; The MOE adopts learnable
decision weights for the ensemble of the experts' outputs. As a model-agnostic
framework, our MEDOE can be flexibly and efficiently coupled with various
popular deep neural networks (e.g., DeepLabv3+, OCRNet, and PSPNet) to improve
their performance in long-tailed semantic segmentation. Experimental results
show that the proposed framework outperforms the current methods on both
Cityscapes and ADE20K datasets by up to 1.78% in mIoU and 5.89% in mAcc.Comment: 18 pages, 9 figure
Rapid detection of sacbrood virus (SBV) by one-step reverse transcription loop-mediated isothermal amplification assay
<p>Abstract</p> <p>Background</p> <p><it>Sacbrood virus </it>(SBV) primarily infects honeybee broods, and in order to deal with the problem cost effective detection methods are required.</p> <p>Findings</p> <p>A one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the rapid identification of SBV. The data demonstrated that, in a simple water bath, SBV RNA could be detected as early as 20 min at 65°C, and a positive amplification reaction was visible to the naked eye due to a color change brought on by the addition of nucleic acid stain SYBR Green.</p> <p>Conclusions</p> <p>The current study presents a method for the rapid and simple detection of SBV by RT-LAMP with high sensitivity and analytic specificity.</p
An Empirical Approach to the Bond Additivity Model in Quantitative Interpretation of Sum Frequency Generation Vibrational Spectra
A complete empirical approach from known Raman and IR spectra is used to make
corrections to the bond additivity model for quantitative interpretation of Sum
Frequency generation Vibrational Spectra (SFG-VS) from molecular interfaces.
This empirical correction successfully addresses the failures of the simple
bond additivity model. This empirical approach not only provides new
understandings of the effectiveness and limitations of the bond additivity
model, but also provides a practical roadmap for its application in SFG-VS
studies of molecular interfaces
Efficient and Product-Controlled Depolymerization of Lignin Oriented by Raney Ni Cooperated with Cs x H3 − x PW12O40.
An Efficient Spatial-Temporal Trajectory Planner for Autonomous Vehicles in Unstructured Environments
As a core part of autonomous driving systems, motion planning has received
extensive attention from academia and industry. However, real-time trajectory
planning capable of spatial-temporal joint optimization is challenged by
nonholonomic dynamics, particularly in the presence of unstructured
environments and dynamic obstacles. To bridge the gap, we propose a real-time
trajectory optimization method that can generate a high-quality whole-body
trajectory under arbitrary environmental constraints. By leveraging the
differential flatness property of car-like robots, we simplify the trajectory
representation and analytically formulate the planning problem while
maintaining the feasibility of the nonholonomic dynamics. Moreover, we achieve
efficient obstacle avoidance with a safe driving corridor for unmodelled
obstacles and signed distance approximations for dynamic moving objects. We
present comprehensive benchmarks with State-of-the-Art methods, demonstrating
the significance of the proposed method in terms of efficiency and trajectory
quality. Real-world experiments verify the practicality of our algorithm. We
will release our codes for the research communit
Comparison of post-Minkowskian and self-force expansions: Scattering in a scalar charge toy model
We compare numerical self-force results and analytical fourth-order
post-Minkowskian (PM) calculations for hyperbolic-type scattering of a
point-like particle carrying a scalar charge off a Schwarzschild black
hole, showing a remarkably good agreement. Specifically, we numerically compute
the scattering angle including the full scalar-field self-force term
(but ignoring the gravitational self-force), and compare with analytical
expressions obtained in a PM framework using scattering-amplitude methods. This
example provides a nontrivial, high-precision test of both calculation methods,
and illustrates the complementarity of the two approaches in the context of the
program to provide high-precision models of gravitational two-body dynamics.
Our PM calculation is carried out through 4PM order, i.e., including all terms
through . At the fourth post-Minkowskian order the point-particle
description involves two a-priori undetermined coefficients, due to
contributions from tidal effects in the model under consideration. These
coefficients are chosen to align the post-Minkowskian results with the
self-force ones.Comment: 53 pages, 11 figures, 7 table
Gold-Catalyzed Tandem Cycloisomerizationand Dimerization of Chiral Homopropargyl Sulfonamides
We are grateful for the financial support from the National Natural Science
Foundation of China (No. 21102119 and 21272191), the Natural Science
Foundation of Fujian Province of China (No. 2012J01051), NFFTBS
(No. J1210014), and PCSIRT. We also thank Professor Dr. Liming Zhang
(University of California Santa Barbara) for the helpful discussions
Physics perspectives of heavy-ion collisions at very high energy
Heavy-ion collisions at very high colliding energies are expected to produce
a quark-gluon plasma (QGP) at the highest temperature obtainable in a
laboratory setting. Experimental studies of these reactions can provide an
unprecedented range of information on properties of the QGP at high
temperatures. We report theoretical investigations of the physics perspectives
of heavy-ion collisions at a future high-energy collider. These include initial
parton production, collective expansion of the dense medium, jet quenching,
heavy-quark transport, dissociation and regeneration of quarkonia, photon and
dilepton production. We illustrate the potential of future experimental studies
of the initial particle production and formation of QGP at the highest
temperature to provide constraints on properties of strongly interaction
matter.Comment: 35 pages in Latex, 29 figure
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