304 research outputs found
Weak Hopf Algebras, Smash Products and Applications to Adjoint-Stable Algebras
For a semisimple quasi-triangular Hopf algebra over a
field of characteristic zero, and a strongly separable quantum commutative
-module algebra over which the Drinfeld element of acts trivially,
we show that is a weak Hopf algebra, and it can be embedded into a weak
Hopf algebra . With these structure,
is the monoidal category introduced by Cohen and
Westreich, and is tensor
equivalent to . If is in the M{\"{u}}ger center of
, then the embedding is a quasi-triangular weak Hopf algebra
morphism. This explains the presence of a subgroup inclusion in the
characterization of irreducible Yetter-Drinfeld modules for a finite group
algebra
Contextual Attention Recurrent Architecture for Context-aware Venue Recommendation
Venue recommendation systems aim to effectively rank a list of interesting venues users should visit based on their historical feedback (e.g. checkins). Such systems are increasingly deployed by Location-based Social Networks (LBSNs) such as Foursquare and Yelp to enhance their usefulness to users. Recently, various RNN architectures have been proposed to incorporate contextual information associated with the users' sequence of checkins (e.g. time of the day, location of venues) to effectively capture the users' dynamic preferences. However, these architectures assume that different types of contexts have an identical impact on the users' preferences, which may not hold in practice. For example, an ordinary context such as the time of the day reflects the user's current contextual preferences, whereas a transition context - such as a time interval from their last visited venue - indicates a transition effect from past behaviour to future behaviour. To address these challenges, we propose a novel Contextual Attention Recurrent Architecture (CARA) that leverages both sequences of feedback and contextual information associated with the sequences to capture the users' dynamic preferences. Our proposed recurrent architecture consists of two types of gating mechanisms, namely 1) a contextual attention gate that controls the influence of the ordinary context on the users' contextual preferences and 2) a time- and geo-based gate that controls the influence of the hidden state from the previous checkin based on the transition context. Thorough experiments on three large checkin and rating datasets from commercial LBSNs demonstrate the effectiveness of our proposed CARA architecture by significantly outperforming many state-of-the-art RNN architectures and factorisation approaches
Generative Modeling in Structural-Hankel Domain for Color Image Inpainting
In recent years, some researchers focused on using a single image to obtain a
large number of samples through multi-scale features. This study intends to a
brand-new idea that requires only ten or even fewer samples to construct the
low-rank structural-Hankel matrices-assisted score-based generative model
(SHGM) for color image inpainting task. During the prior learning process, a
certain amount of internal-middle patches are firstly extracted from several
images and then the structural-Hankel matrices are constructed from these
patches. To better apply the score-based generative model to learn the internal
statistical distribution within patches, the large-scale Hankel matrices are
finally folded into the higher dimensional tensors for prior learning. During
the iterative inpainting process, SHGM views the inpainting problem as a
conditional generation procedure in low-rank environment. As a result, the
intermediate restored image is acquired by alternatively performing the
stochastic differential equation solver, alternating direction method of
multipliers, and data consistency steps. Experimental results demonstrated the
remarkable performance and diversity of SHGM.Comment: 11 pages, 10 figure
Changes in the Interstitial Cells of Cajal and Immunity in Chronic Psychological Stress Rats and Therapeutic Effects of Acupuncture at the Zusanli Point (ST36)
Now, chronic psychological stress (CPS) related diseases are increasing. Many CPS patients have gastrointestinal complaints, immune suppression, and immune imbalance. Increasing evidence is indicating that acupuncture (AP) at the Zusanli point (ST36) can alleviate functional gastrointestinal disorders (FGID), immune suppression, and immune imbalance. However, few studies have investigated the potential mechanisms. In this study, CPS rat models were established, and electroacupuncture (EA) at ST36 was done for CPS rats. Daily food intake, weight, intestinal sensitivity, the morphology of interstitial cell of Cajal (ICC) in the small intestine, and serum indexes were measured. The study found that, in CPS rats, EA at ST36 could improve food intake, weight, visceral hypersensitivity, and immunity; in CPS rats, in small intestine, the morphology of ICCs was abnormal and the number was decreased, which may be part causes of gastrointestinal motility dysfunction. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its repairing effects on ICCs damages; in CPS rats, there were immune suppression and immune imbalance, which may be part causes of visceral hypersensitivity. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its regulation on immunity
Recommended from our members
CR Cistrome: a ChIP-Seq database for chromatin regulators and histone modification linkages in human and mouse
Diversified histone modifications (HMs) are essential epigenetic features. They play important roles in fundamental biological processes including transcription, DNA repair and DNA replication. Chromatin regulators (CRs), which are indispensable in epigenetics, can mediate HMs to adjust chromatin structures and functions. With the development of ChIP-Seq technology, there is an opportunity to study CR and HM profiles at the whole-genome scale. However, no specific resource for the integration of CR ChIP-Seq data or CR-HM ChIP-Seq linkage pairs is currently available. Therefore, we constructed the CR Cistrome database, available online at http://compbio.tongji.edu.cn/cr and http://cistrome.org/cr/, to further elucidate CR functions and CR-HM linkages. Within this database, we collected all publicly available ChIP-Seq data on CRs in human and mouse and categorized the data into four cohorts: the reader, writer, eraser and remodeler cohorts, together with curated introductions and ChIP-Seq data analysis results. For the HM readers, writers and erasers, we provided further ChIP-Seq analysis data for the targeted HMs and schematized the relationships between them. We believe CR Cistrome is a valuable resource for the epigenetics community
Shale gas geological characteristics and exploration potential of lower permian Taiyuan Formation in Linxing Area
In order to reveal the geological characteristics and exploration potential of shale gas in Taiyuan Formation in Linxing area, eastern Ordos Basin, taking organic-rich mud shale as the research object, the distribution rules of mud shale cumulative thickness and single layer maximum thickness were found out based on field drilling and logging geological data. The organic geochemistry, physical properties, X-ray diffraction and isothermal adsorption experiments were carried out for shales, and the accumulation conditions and exploration potential of shale gas were studied. The results show that the distribution of mud shale in Taiyuan Formation in Linxing area is stable, the cumulative thickness is 10-50 m, the average thickness is 30 m, and the maximum thickness of single layer is 5−25 m. The Organic matter abundance is high, TOC content is 0.26%-12%, with an average value of 3.81%. Organic matter type is mainly II and III kerogen, and peak temperature of pyrolysis is between 443 ℃ and 576 ℃. The thermal maturity of shale near zijinshan rock mass increases obviously. The pores and fissures of nanoscale–micron scale are developed in shales. The pores of organic matter are mostly round, oval and honeycomb. Other types of pores such as the dissolution pores of clastic minerals are developed. The microcracks in mineral particles, the edge of clastic particles and the internal organic matter are relatively developed. The content of brittle minerals such as quartz and feldspar are 45%-65%, and the content of clay minerals is 28%-62%, which are mostly non-expansive minerals. The variation range of gas content in shale is large, ranging from 0.08 m3/t to 7.3 m3/t, with an average value of 1.41 m3/t. There is a significant positive correlation between gas content and TOC. Considering the factors such as shale thickness, organic matter abundance and thermal evolution degree, the central and northern shale in Linxing area has large thickness and high TOC content. The mineral assemblage is conducive to reservoir reconstruction and is a favorable area for shale gas exploration. Compared with marine shale gas exploration area in Sichuan Basin, Taiyuan Formation shale in Linxing area has the characteristics of shallow burial depth and low gas content. In the exploration and development of oil and gas resources, it is necessary to pay attention to the joint exploration and development of sandstone gas and coalbed methane in coal measure strata
Extreme Mitogenomic Variation in Natural Populations of Chaetognaths
The extent of within-species genetic variation across the diversity of animal life is an underexplored problem in ecology and evolution. Although neutral genetic variation should scale positively with population size, mitochondrial diversity levels are believed to show little variation across animal species. Here, we report an unprecedented case of extreme mitochondrial diversity within natural populations of two morphospecies of chaetognaths (arrow worms). We determine that this diversity is composed of deep sympatric mitochondrial lineages, which are in some cases as divergent as human and platypus. Additionally, based on 54 complete mitogenomes, we observed mitochondrial gene order differences between several of these lineages. We examined nuclear divergence patterns (18S, 28S, and an intron) to determine the possible origin of these lineages, but did not find congruent patterns between mitochondrial and nuclear markers. We also show that extreme mitochondrial divergence in chaetognaths is not driven by positive selection. Hence, we propose that the extreme levels of mitochondrial variation could be the result of either a complex scenario of reproductive isolation, or a combination of large population size and accelerated mitochondrial mutation rate. These findings emphasize the importance of characterizing genome-wide levels of nuclear variation in these species and promote chaetognaths as a remarkable model to study mitochondrial evolution
Cytoplasmic DNAs: Sources, sensing, and roles in the development of lung inflammatory diseases and cancer
Cytoplasmic DNA is emerging as a pivotal contributor to the pathogenesis of inflammatory diseases and cancer, such as COVID-19 and lung carcinoma. However, the complexity of various cytoplasmic DNA-related pathways and their crosstalk remains challenging to distinguish their specific roles in many distinct inflammatory diseases, especially for the underlying mechanisms. Here, we reviewed the latest findings on cytoplasmic DNA and its signaling pathways in inflammatory lung conditions and lung cancer progression. We found that sustained activation of cytoplasmic DNA sensing pathways contributes to the development of common lung diseases, which may result from external factors or mutations of key genes in the organism. We further discussed the interplays between cytoplasmic DNA and anti-inflammatory or anti-tumor effects for potential immunotherapy. In sum, this review aids in understanding the roles of cytoplasmic DNAs and exploring more therapeutic strategies
- …