Hierarchical Graph Transformer with Adaptive Node Sampling

The Transformer architecture has achieved remarkable success in a number of domains including natural language processing and computer vision. However, when it comes to graph-structured data, transformers have not achieved competitive performance, especially on large graphs. In this paper, we identify the main deficiencies of current graph transformers:(1) Existing node sampling strategies in Graph Transformers are agnostic to the graph characteristics and the training process. (2) Most sampling strategies only focus on local neighbors and neglect the long-range dependencies in the graph. We conduct experimental investigations on synthetic datasets to show that existing sampling strategies are sub-optimal. To tackle the aforementioned problems, we formulate the optimization strategies of node sampling in Graph Transformer as an adversary bandit problem, where the rewards are related to the attention weights and can vary in the training procedure. Meanwhile, we propose a hierarchical attention scheme with graph coarsening to capture the long-range interactions while reducing computational complexity. Finally, we conduct extensive experiments on real-world datasets to demonstrate the superiority of our method over existing graph transformers and popular GNNs.Comment: Accepted by NeurIPS 202

FedGT: Federated Node Classification with Scalable Graph Transformer

Graphs are widely used to model relational data. As graphs are getting larger and larger in real-world scenarios, there is a trend to store and compute subgraphs in multiple local systems. For example, recently proposed \emph{subgraph federated learning} methods train Graph Neural Networks (GNNs) distributively on local subgraphs and aggregate GNN parameters with a central server. However, existing methods have the following limitations: (1) The links between local subgraphs are missing in subgraph federated learning. This could severely damage the performance of GNNs that follow message-passing paradigms to update node/edge features. (2) Most existing methods overlook the subgraph heterogeneity issue, brought by subgraphs being from different parts of the whole graph. To address the aforementioned challenges, we propose a scalable \textbf{Fed}erated \textbf{G}raph \textbf{T}ransformer (\textbf{FedGT}) in the paper. Firstly, we design a hybrid attention scheme to reduce the complexity of the Graph Transformer to linear while ensuring a global receptive field with theoretical bounds. Specifically, each node attends to the sampled local neighbors and a set of curated global nodes to learn both local and global information and be robust to missing links. The global nodes are dynamically updated during training with an online clustering algorithm to capture the data distribution of the corresponding local subgraph. Secondly, FedGT computes clients' similarity based on the aligned global nodes with optimal transport. The similarity is then used to perform weighted averaging for personalized aggregation, which well addresses the data heterogeneity problem. Moreover, local differential privacy is applied to further protect the privacy of clients. Finally, extensive experimental results on 6 datasets and 2 subgraph settings demonstrate the superiority of FedGT.Comment: ICLR 24 submissio

Chinese Herbal Formula Xiao Yao San for Treatment of Depression: A Systematic Review of Randomized Controlled Trials

Objectives. To assess the beneficial and adverse effects of Xiaoyaosan for depression. Search Strategy. Electronic databases were searched until December 2009. Inclusion Criteria. We included randomized clinical trials testing Xiaoyaosan against placebo, antidepressants, or combined with antidepressants against antidepressants alone. Data Extraction and Analyses. Study selection, data extraction, quality assessment, and data analyses were conducted according to the Cochrane standards. Results. 26 randomized trials (involving 1837 patients) were included and the methodological quality was evaluated as generally low. The pooled results showed that Xiaoyaosan combined with antidepressants was more effective in comprehensive effect, the score of HAMD and the score of SDS compared with antidepressants alone. Xiaoyaosan was superior to antidepressants for the score of HAMD. However, Xiaoyaosan was not different from placebo for the score of SDS. There was no adverse effects reported in the trials from Xiaoyaosan. Conclusions. Xiaoyaosan appears to be effective on improving symptoms in patients with depression. However, due to poor methodological quality in the majority of included trials, the potential benefit from Xiaoyaosan need to be confirmed in rigorous trials and the design and reporting of trials should follow international standards

VEGF Is Involved in the Increase of Dermal Microvascular Permeability Induced by Tryptase

Tryptases are predominantly mast cell-specific serine proteases with pleiotropic biological activities and play a critical role in skin allergic reactions, which are manifested with rapid edema and increases of vascular permeability. The exact mechanisms of mast cell tryptase promoting vascular permeability, however, are unclear and, therefore, we investigated the effect and mechanism of tryptase or human mast cells (HMC-1) supernatant on the permeability of human dermal microvascular endothelial cells (HDMECs). Both tryptase and HMC-1 supernatant increased permeability of HDMECs significantly, which was resisted by tryptase inhibitor APC366 and partially reversed by anti-VEGF antibody and SU5614 (catalytic inhibitor of VEGFR). Furthermore, addition of tryptase to HDMECs caused a significant increase of mRNA and protein levels of VEGF and its receptors (Flt-1 and Flk-1) by Real-time RT-PCR and Western blot, respectively. These results strongly suggest an important role of VEGF on the permeability enhancement induced by tryptase, which may lead to novel means of controlling allergic reaction in skin

Experimental study on the combustion and explosion process induced by the entrainment of deposited coal dust

During the operation of pulverizing systems in power plants, high ambient temperatures create conditions in which coal dust deposited on equipment surfaces is prone to thermal runaway. When these self-ignited coal dust particles are lifted by airflow, there is a significant risk of combustion and explosion. To reveal the processes and mechanisms of dust cloud explosions induced by airflow entrainment, we constructed an experimental setup to monitor coal dust self-ignition, dispersion in a dust cloud, and the subsequent ignition and explosion. Next, we investigated the self-ignition process, characteristic parameters, critical conditions for entrainment-induced explosions, explosion behavior, and underlying mechanisms. The experimental procedure involved first placing the coal powder on a high-temperature flat plate and then using a high-pressure airflow to entrain the coal powder into the air under various spontaneous combustion conditions. Subsequently, the phenomena of spontaneous combustion, explosion, and their transitions were observed. The results indicated that thermal conduction and oxidative heat release were the primary causes of high-temperature spot migration during the self-ignition process of the deposited coal dust, with the high-temperature point moving upward from the hot surface and then downward. As the deposition thickness increased, both the peak temperature and the duration of the combustion propagation and decay stages increased, reaching 538 ℃, 510 ℃, 810 s, and 1520 s for thicknesses of 8 mm and 10 mm, respectively. The degree of self-ignition and the mass of coal dust significantly influenced the occurrence of explosions, with the central temperature representing the self-ignition level. When the central temperature of the coal dust layer ranged from 280 ℃ to 420 ℃, the entrained coal dust could trigger an explosion. As the central temperature increased, the flame propagation speed first increased and then decreased, whereas the particle size and surface smoothness of the solid residue decreases. The flame propagation speed of the explosion was the largest (4.76 m·s−1) at a mass of 6.0 g and central temperature of 340 ℃. Additionally, the explosion intensity initially increased and then decreased with an increasing coal dust mass. Moreover, the maximum flame length and flame area occurred at 6.0 g, measuring 26.81 cm and 301.4 cm2, respectively. A lower dust mass resulted in insufficient combustible particles, leading to a decrease in flame intensity, whereas a higher dust mass limited combustion owing to an inadequate oxygen supply. Furthermore, the combined effects of the heterogeneous combustion of carbon particles and homogeneous combustion of volatiles, such as CO and H2, are the primary trigger mechanisms driving the explosion of deposited coal dust. The homogeneous combustion of combustible gases ignited the coal dust particles, thus further promoting the pyrolysis and combustion of coal dust, and producing more combustible gases and strengthening the explosion process. When coal dust has a low concentration and a low degree of spontaneous combustion, the combustion and explosions are dominated by heterogeneous combustion. Additionally, the coupling of these two ignition mechanisms leads to incomplete combustion, secondary ignition, and multiple ignition sources. This study provides a theoretical basis for the prevention and control of spontaneous combustion-induced explosion hazards in pulverized industrial systems

Effect of the combination of cognitive behavioral therapy and oral paroxetine hydrochloride in patients with post-stroke depression

Purpose: To determine the effects of combined use of cognitive behavioral therapy (CBT) and paroxetine hydrochloride tablets in patients with post-stroke depression (PSD), and its effect on scores on Hamilton Rating Scale for Depression (HAMD) and Stroke Specific Quality of Life Scale (SS-QOL). Methods: Clinical data for 96 patients with PSD who were treated in Dongying Traditional Chinese Hospital, Dongying City, China from June 2018 to June 2019 were retrospectively analyzed. Patients who met the inclusion criteria were divided into treatment group (TG, n = 48) and reference group (RG, n = 48) based on odd and even hospitalization numbers. Both groups received conventional treatment, but RG patients were in addition given clopidogrel, while TG received CBT in combination with paroxetine hydrochloride tablets. Clinical indices were evaluated in both groups before and after treatment. Moreover, therapeutic effects in the two different treatment methods on PSD, as well as on Hamilton Rating Scale for Depression (HAMD) and Stroke Specific Quality of Life Scale (SS-QOL) scores were analyzed. Results: After treatment, TG had lower HAMD score (p < 0.001), lower scores on modified Rankin scale, and few incidences of adverse reactions at 3, 7, 15 and 30 days of treatment (p < 0.05), but higher total clinical effectiveness and mean SS-QOL score (p < 0.05), when compared with RG. Conclusion: Combined use of CBT and oral paroxetine hydrochloride tablets may be a promising strategy for treating depression and enhancing the quality of life of PSD patients, as it greatly improves neurological deficit and prognosis. However, further clinical trials should be carried out prior to introducing it in clinical practice

Formation conditions and enrichment mechanisms of the Jurassic lacustrine organic-rich shale in the East Fukang Sag, Junggar Basin, NW China: A reassessment based on organic geochemistry

Chemical composition of sediments is often used to evaluate paleoclimate condition, provenance, tectonic setting, depositional condition, and paleoproductivity. However, the validity of these proxies has long been questioned. The comprehensive use of organic and inorganic multi-indicators in combination when interpreting issues related to terrestrial shales should be advocated. The paleodepositional environment, origin of organic matter (OM) and factor controlling OM accumulation in the Early Jurassic Badaowan (J1b) and Sangonghe (J1s) as well as Middle Jurassic Xishanyao (J2x) lacustrine shales in the East Fukang Sag are reassessed by using organic geochemical characteristics of the OM. Some previous knowledge is updated, and some knowledge is further supported by more evidence. The typical clay-rich shale developed under a lacustrine sedimental environment, and the thermal maturity of these organic-rich shales has entered the oil window and formed economic hydrocarbon potential for the tight-oil and shale-oil reservoirs. The paleoclimate conditions of the study area were warm and humid from the Early to Middle Jurassic periods but were colder and drier after the Middle Jurassic period. The salinity of the water column ranged from freshwater to brackish conditions. The J2x Formation was deposited under oxic conditions, while J1b and J1s formations developed under suboxic and reducing environmental conditions. The J2x Formation OM mainly derived from higher plants was deposited in a terrestrial environment,while the OM of J1b and J1s formations was a mixed OM derived from higher plants and bacteria with little algae deposited under bay/estuary environments alternated with terrestrial environments. It is effective to reflect the paleoclimate by element index and judge the salinity by the updated element thresholds, but it is not effective to evaluate the paleoredox conditions by common elemental ratios and to evaluate the paleoproductivity by Ba in the study area

Analysis of Immunoglobulin Transcripts in the Ostrich Struthio camelus, a Primitive Avian Species

Previous studies on the immunoglobulin (Ig) genes in avian species are limited (mainly to galliformes and anseriformes) but have revealed several interesting features, including the absence of the IgD and Igκ encoding genes, inversion of the IgA encoding gene and the use of gene conversion as the primary mechanism to generate an antibody repertoire. To better understand the Ig genes and their evolutionary development in birds, we analyzed the Ig genes in the ostrich (Struthio camelus), which is one of the most primitive birds. Similar to the chicken and duck, the ostrich expressed only three IgH chain isotypes (IgM, IgA and IgY) and λ light chains. The IgM and IgY constant domains are similar to their counterparts described in other vertebrates. Although conventional IgM, IgA and IgY cDNAs were identified in the ostrich, we also detected a transcript encoding a short membrane-bound form of IgA (lacking the last two CH exons) that was undetectable at the protein level. No IgD or κ encoding genes were identified. The presence of a single leader peptide in the expressed heavy chain and light chain V regions indicates that gene conversion also plays a major role in the generation of antibody diversity in the ostrich. Because the ostrich is one of the most primitive living aves, this study suggests that the distinct features of the bird Ig genes appeared very early during the divergence of the avian species and are thus shared by most, if not all, avian species