655 research outputs found
Melanoma-specific mortality and competing mortality in patients with non-metastatic malignant melanoma: a population-based analysis
Diversity is Strength: Mastering Football Full Game with Interactive Reinforcement Learning of Multiple AIs
Training AI with strong and rich strategies in multi-agent environments
remains an important research topic in Deep Reinforcement Learning (DRL). The
AI's strength is closely related to its diversity of strategies, and this
relationship can guide us to train AI with both strong and rich strategies. To
prove this point, we propose Diversity is Strength (DIS), a novel DRL training
framework that can simultaneously train multiple kinds of AIs. These AIs are
linked through an interconnected history model pool structure, which enhances
their capabilities and strategy diversities. We also design a model evaluation
and screening scheme to select the best models to enrich the model pool and
obtain the final AI. The proposed training method provides diverse,
generalizable, and strong AI strategies without using human data. We tested our
method in an AI competition based on Google Research Football (GRF) and won the
5v5 and 11v11 tracks. The method enables a GRF AI to have a high level on both
5v5 and 11v11 tracks for the first time, which are under complex multi-agent
environments. The behavior analysis shows that the trained AI has rich
strategies, and the ablation experiments proved that the designed modules
benefit the training process
Early identification of mild cognitive impairment using incomplete random forest-robust support vector machine and FDG-PET imaging
Alzheimerâs disease (AD) is the most common type of dementia and will be an increasing health problem in society as the population ages. Mild cognitive impairment (MCI) is considered to be a prodromal stage of AD. The ability to identify subjects with MCI will be increasingly important as disease modifying therapies for AD are developed. We propose a semi-supervised learning method based on robust optimization for the identification of MCI from [18F]Fluorodeoxyglucose PET scans. We extracted three groups of spatial features from the cortical and subcortical regions of each FDG-PET image volume. We measured the statistical uncertainty related to these spatial features via transformation using an incomplete random forest and formulated the MCI identification problem under a robust optimization framework. We compared our approach to other state-of-the-art methods in different learning schemas. Our method outperformed the other techniques in the ability to separate MCI from normal controls
PD-1 expression on peripheral CD8+ TEM/TEMRA subsets closely correlated with HCV viral load in chronic hepatitis C patients
<p>Abstract</p> <p>Background</p> <p>Tight correlation between host circulating CD8+ T cell-mediated immune response and control of viral replication is classical characteristic of long-term HCV infection. CD8+ T cell maturation/activation markers are expected to be associated with viral replication and disease progression in chronic HCV infection. The aim of the present study was to explore novel markers on CD8+ T cells with ability to evaluate HCV viral replication and disease progression.</p> <p>Methods</p> <p>PBMCs were isolated from 37 chronic HCV-infected patients and 17 healthy controls. Distributed pattern of CD8+ T cells subsets and expression of PD-1, CD38, HLA-DR and CD127 were analyzed by flow cytometry. The correlation between expression of surface markers and HCV viral load or ALT was studied.</p> <p>Results</p> <p>Declined naĂŻve and increased TEMRA CD8+ T subsets were found in HCV-infected individuals compared with healthy controls. Percentage and MFI of PD-1, CD38 and HLA-DR on all CD8+ T cell subsets were higher in HCV-infected patients than healthy controls. In contrast, CD127 expression on CD8+ TCM showed an opposite trend as PD-1, CD38 and HLA-DR did. In chronic HCV infection, MFI of PD-1 on CD8+ TEM (p < 0.0001) and TEMRA (p = 0.0015) was positively correlated with HCV viral load while HLA-DR expression on non-naive CD8+ T cell subsets (p < 0.05) was negatively correlated with HCV viral load.</p> <p>Conclusion</p> <p>PD-1 level on peripheral CD8+ TEM/TEMRA was highly correlated with HCV viral load in chronic HCV-infected patients, which made PD-1 a novel indicator to evaluate HCV replication and disease progression in chronic hepatitis C patients.</p
Human connectome module pattern detection using a new multi-graph MinMax cut model
Many recent scientific efforts have been devoted to constructing the human connectome using Diffusion Tensor Imaging (DTI) data for understanding the large-scale brain networks that underlie higher-level cognition in human. However, suitable computational network analysis tools are still lacking in human connectome research. To address this problem, we propose a novel multi-graph min-max cut model to detect the consistent network modules from the brain connectivity networks of all studied subjects. A new multi-graph MinMax cut model is introduced to solve this challenging computational neuroscience problem and the efficient optimization algorithm is derived. In the identified connectome module patterns, each network module shows similar connectivity patterns in all subjects, which potentially associate to specific brain functions shared by all subjects. We validate our method by analyzing the weighted fiber connectivity networks. The promising empirical results demonstrate the effectiveness of our method
Restoration of Mangrove Plantations and Colonisation by Native Species in Leizhou Bay, South China
To examine the natural colonization of native mangrove species into remediated exotic mangrove stands in Leizhou Bay, South China, we compared soil physicalâchemical properties, community structure and recruitments of barren mangrove areas, native mangrove species plantations, and exotic mangrove speciesâSonneratia apetala Buch.Hamâbetween plantations and natural forest. We found that severely degraded mangrove stands could not regenerate naturally without human intervention due to severely altered local environments, whereas some native species had been recruited into the 4â10 year S. apetala plantations. In the first 10 years, the exotic species S. apetala grew better than native species such as Rhizophora stylosa Griff and Kandelia candel (Linn.) Druce. The mangrove plantation gradually affected soil physical and chemical properties during its recovery. The exotic S. apetala was more competitive than native species and its plantation was able to restore soil organic matter in about 14 years. Thus, S. apetala can be considered as a pioneer species to improve degraded habitats to facilitate recolonization by native mangrove species. However, removal to control proliferation may be needed at late stages to facilitate growth of native species. To ensure sustainability of mangroves in South China, the existing mangrove wetlands must be managed as an ecosystem, with long-term scientific monitoring program in place
Restoration of Mangrove Plantations and Colonisation by Native Species in Leizhou Bay, South China
To examine the natural colonization of native mangrove species into remediated exotic mangrove stands in Leizhou Bay, South China, we compared soil physicalâchemical properties, community structure and recruitments of barren mangrove areas, native mangrove species plantations, and exotic mangrove speciesâSonneratia apetala Buch.Hamâbetween plantations and natural forest. We found that severely degraded mangrove stands could not regenerate naturally without human intervention due to severely altered local environments, whereas some native species had been recruited into the 4â10 year S. apetala plantations. In the first 10 years, the exotic species S. apetala grew better than native species such as Rhizophora stylosa Griff and Kandelia candel (Linn.) Druce. The mangrove plantation gradually affected soil physical and chemical properties during its recovery. The exotic S. apetala was more competitive than native species and its plantation was able to restore soil organic matter in about 14 years. Thus, S. apetala can be considered as a pioneer species to improve degraded habitats to facilitate recolonization by native mangrove species. However, removal to control proliferation may be needed at late stages to facilitate growth of native species. To ensure sustainability of mangroves in South China, the existing mangrove wetlands must be managed as an ecosystem, with long-term scientific monitoring program in place
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