7 research outputs found
Vision Transformer with Attentive Pooling for Robust Facial Expression Recognition
Facial Expression Recognition (FER) in the wild is an extremely challenging
task. Recently, some Vision Transformers (ViT) have been explored for FER, but
most of them perform inferiorly compared to Convolutional Neural Networks
(CNN). This is mainly because the new proposed modules are difficult to
converge well from scratch due to lacking inductive bias and easy to focus on
the occlusion and noisy areas. TransFER, a representative transformer-based
method for FER, alleviates this with multi-branch attention dropping but brings
excessive computations. On the contrary, we present two attentive pooling (AP)
modules to pool noisy features directly. The AP modules include Attentive Patch
Pooling (APP) and Attentive Token Pooling (ATP). They aim to guide the model to
emphasize the most discriminative features while reducing the impacts of less
relevant features. The proposed APP is employed to select the most informative
patches on CNN features, and ATP discards unimportant tokens in ViT. Being
simple to implement and without learnable parameters, the APP and ATP
intuitively reduce the computational cost while boosting the performance by
ONLY pursuing the most discriminative features. Qualitative results demonstrate
the motivations and effectiveness of our attentive poolings. Besides,
quantitative results on six in-the-wild datasets outperform other
state-of-the-art methods.Comment: Codes will be public on https://github.com/youqingxiaozhua/APVi
The Brassica oleracea genome reveals the asymmetrical evolution of polyploid genomes
Polyploidization has provided much genetic variation for plant adaptive evolution, but the mechanisms by which the molecular evolution of polyploid genomes establishes genetic architecture underlying species differentiation are unclear. Brassica is an ideal model to increase knowledge of polyploid evolution. Here we describe a draft genome sequence of Brassica oleracea, comparing it with that of its sister species B. rapa to reveal numerous chromosome rearrangements and asymmetrical gene loss in duplicated genomic blocks, asymmetrical amplification of transposable elements, differential gene co-retention for specific pathways and variation in gene expression, including alternative splicing, among a large number of paralogous and orthologous genes. Genes related to the production of anticancer phytochemicals and morphological variations illustrate consequences of genome duplication and gene divergence, imparting biochemical and morphological variation to B. oleracea. This study provides insights into Brassica genome evolution and will underpin research into the many important crops in this genus.Peer reviewed: YesNRC publication: Ye
Early allopolyploid evolution in the post-Neolithic Brassica napus oilseed genome
Oilseed rape (Brassica napus L.) was formed ~7500 years ago by hybridization between B. rapa and B. oleracea, followed by chromosome doubling, a process known as allopolyploidy. Together with more ancient polyploidizations, this conferred an aggregate 72× genome multiplication since the origin of angiosperms and high gene content. We examined the B. napus genome and the consequences of its recent duplication. The constituent An and Cn subgenomes are engaged in subtle structural, functional, and epigenetic cross-talk, with abundant homeologous exchanges. Incipient gene loss and expression divergence have begun. Selection in B. napus oilseed types has accelerated the loss of glucosinolate genes, while preserving expansion of oil biosynthesis genes. These processes provide insights into allopolyploid evolution and its relationship with crop domestication and improvement
The Brassica oleracea genome reveals the asymmetrical evolution of polyploid genomes
Polyploidization has provided much genetic variation for plant adaptive evolution, but the mechanisms by which the molecular evolution of polyploid genomes establishes genetic architecture underlying species differentiation are unclear. Brassica is an ideal model to increase knowledge of polyploid evolution. Here we describe a draft genome sequence of Brassica oleracea, comparing it with that of its sister species B. rapa to reveal numerous chromosome rearrangements and asymmetrical gene loss in duplicated genomic blocks, asymmetrical amplification of transposable elements, differential gene co-retention for specific pathways and variation in gene expression, including alternative splicing, among a large number of paralogous and orthologous genes. Genes related to the production of anticancer phytochemicals and morphological variations illustrate consequences of genome duplication and gene divergence, imparting biochemical and morphological variation to B. oleracea. This study provides insights into Brassica genome evolution and will underpin research into the many important crops in this genus