313 research outputs found
Organic Anti-counterfeiting Techniques in China
The development of organic label anti-counterfeiting techniques in China has been introduced, including three generations of the techniques, especially the third-generation QR Code organic anti-counterfeiting traceable label. How to use the anti-counterfeiting techniques to enable the organic products to be “easy in identification, traceable in information and controllable in quantity”, how to enhance consumers’ recognition and how to power the government's regulation enforcement on organic market were demonstrated
A comparative theoretical study on core-hole excitation spectra of azafullerene and its derivatives
Phylogenetic Molecular Ecological Network of Soil Microbial Communities in Response to Elevated CO2
Understanding the interactions among different species and their responses to environmental changes, such as elevated atmospheric concentrations of CO2, is a central goal in ecology but is poorly understood in microbial ecology. Here we describe a novel random matrix theory (RMT)-based conceptual framework to discern phylogenetic molecular ecological networks using metagenomic sequencing data of 16S rRNA genes from grassland soil microbial communities, which were sampled from a long-term free-air CO2 enrichment experimental facility at the Cedar Creek Ecosystem Science Reserve in Minnesota. Our experimental results demonstrated that an RMT-based network approach is very useful in delineating phylogenetic molecular ecological networks of microbial communities based on high-throughput metagenomic sequencing data. The structure of the identified networks under ambient and elevated CO2 levels was substantially different in terms of overall network topology, network composition, node overlap, module preservation, module-based higher-order organization, topological roles of individual nodes, and network hubs, suggesting that the network interactions among different phylogenetic groups/populations were markedly changed. Also, the changes in network structure were significantly correlated with soil carbon and nitrogen contents, indicating the potential importance of network interactions in ecosystem functioning. In addition, based on network topology, microbial populations potentially most important to community structure and ecosystem functioning can be discerned. The novel approach described in this study is important not only for research on biodiversity, microbial ecology, and systems microbiology but also for microbial community studies in human health, global change, and environmental management
Pure Monte Carlo Counterfactual Regret Minimization
Counterfactual Regret Minimization (CFR) and its variants are the best
algorithms so far for solving large-scale incomplete information games.
Building upon CFR, this paper proposes a new algorithm named Pure CFR (PCFR)
for achieving better performance. PCFR can be seen as a combination of CFR and
Fictitious Play (FP), inheriting the concept of counterfactual regret (value)
from CFR, and using the best response strategy instead of the regret matching
strategy for the next iteration. Our theoretical proof that PCFR can achieve
Blackwell approachability enables PCFR's ability to combine with any CFR
variant including Monte Carlo CFR (MCCFR). The resultant Pure MCCFR (PMCCFR)
can significantly reduce time and space complexity. Particularly, the
convergence speed of PMCCFR is at least three times more than that of MCCFR. In
addition, since PMCCFR does not pass through the path of strictly dominated
strategies, we developed a new warm-start algorithm inspired by the strictly
dominated strategies elimination method. Consequently, the PMCCFR with new warm
start algorithm can converge by two orders of magnitude faster than the CFR+
algorithm
Multiscale Global Adaptive Attention Graph Neural Network
Dynamic multiscale graph neural networks have high motion prediction errors due to the low correlation between the internal joints of body parts and the limited perceptual fields. A multiscale global adaptive attention graph neural network for human motion prediction is proposed to reduce motion prediction errors. Firstly, a multi-distance partitioning strategy for dividing skeleton joint is proposed to improve the degree of temporal and spatial correlation of body joint information. Secondly, a global adaptive attention spatial temporal graph convolutional network is designed to dynamically enhance the network??s attention to the spatial temporal joints contributing to a motion in combination with global adaptive attention. Finally, this paper integrates the above two improvements into the graph convolutional neural network gate recurrent unit to enhance the state propagation performance of the decoding network and reduce prediction errors. Experimental results show that the prediction error of the proposed method is decreased on Human 3.6M dataset, CMU Mocap dataset and 3DPW dataset compared with state-of-the-art methods
Constructing gene co-expression networks and predicting functions of unknown genes by random matrix theory
<p>Abstract</p> <p>Background</p> <p>Large-scale sequencing of entire genomes has ushered in a new age in biology. One of the next grand challenges is to dissect the cellular networks consisting of many individual functional modules. Defining co-expression networks without ambiguity based on genome-wide microarray data is difficult and current methods are not robust and consistent with different data sets. This is particularly problematic for little understood organisms since not much existing biological knowledge can be exploited for determining the threshold to differentiate true correlation from random noise. Random matrix theory (RMT), which has been widely and successfully used in physics, is a powerful approach to distinguish system-specific, non-random properties embedded in complex systems from random noise. Here, we have hypothesized that the universal predictions of RMT are also applicable to biological systems and the correlation threshold can be determined by characterizing the correlation matrix of microarray profiles using random matrix theory.</p> <p>Results</p> <p>Application of random matrix theory to microarray data of <it>S. oneidensis</it>, <it>E. coli</it>, yeast, <it>A. thaliana</it>, <it>Drosophila</it>, mouse and human indicates that there is a sharp transition of nearest neighbour spacing distribution (NNSD) of correlation matrix after gradually removing certain elements insider the matrix. Testing on an <it>in silico </it>modular model has demonstrated that this transition can be used to determine the correlation threshold for revealing modular co-expression networks. The co-expression network derived from yeast cell cycling microarray data is supported by gene annotation. The topological properties of the resulting co-expression network agree well with the general properties of biological networks. Computational evaluations have showed that RMT approach is sensitive and robust. Furthermore, evaluation on sampled expression data of an <it>in silico </it>modular gene system has showed that under-sampled expressions do not affect the recovery of gene co-expression network. Moreover, the cellular roles of 215 functionally unknown genes from yeast, <it>E. coli </it>and <it>S. oneidensis </it>are predicted by the gene co-expression networks using guilt-by-association principle, many of which are supported by existing information or our experimental verification, further demonstrating the reliability of this approach for gene function prediction.</p> <p>Conclusion</p> <p>Our rigorous analysis of gene expression microarray profiles using RMT has showed that the transition of NNSD of correlation matrix of microarray profile provides a profound theoretical criterion to determine the correlation threshold for identifying gene co-expression networks.</p
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