9 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 transcriptional factor Clr-5 is involved in cellulose degradation through regulation of amino acid metabolism in Neurospora crassa
Abstract Background Filamentous fungi are efficient degraders of plant biomass and the primary producers of commercial cellulolytic enzymes. While the transcriptional regulation mechanisms of cellulases have been continuously explored in lignocellulolytic fungi, the induction of cellulase production remains a complex multifactorial system, with several aspects still largely elusive. Results In this study, we identified a Zn2Cys6 transcription factor, designated as Clr-5, which regulates the expression of cellulase genes by influencing amino acid metabolism in Neurospora crassa during growth on cellulose. The deletion of clr-5 caused a significant decrease in secreted protein and cellulolytic enzyme activity of N. crassa, which was partially alleviated by supplementing with yeast extract. Transcriptomic profiling revealed downregulation of not only the genes encoding main cellulases but also those related to nitrogen metabolism after disruption of Clr-5 under Avicel condition. Clr-5 played a crucial role in the utilization of multiple amino acids, especially leucine and histidine. When using leucine or histidine as the sole nitrogen source, the Δclr-5 mutant showed significant growth defects on both glucose and Avicel media. Comparative transcriptomic analysis revealed that the transcript levels of most genes encoding carbohydrate-active enzymes and those involved in the catabolism and uptake of histidine, branched-chain amino acids, and aromatic amino acids, were remarkably reduced in strain Δclr-5, compared with the wild-type N. crassa when grown in Avicel medium with leucine or histidine as the sole nitrogen source. These findings underscore the important role of amino acid metabolism in the regulation of cellulase production in N. crassa. Furthermore, the function of Clr-5 in regulating cellulose degradation is conserved among ascomycete fungi. Conclusions These findings regarding the novel transcription factor Clr-5 enhance our comprehension of the regulatory connections between amino acid metabolism and cellulase production, offering fresh prospects for the development of fungal cell factories dedicated to cellulolytic enzyme production in bio-refineries
High-Field Asymmetric Waveform Ion Mobility Spectrometry Interface Enhances Parallel Reaction Monitoring on an Orbitrap Mass Spectrometer
High-field asymmetric
waveform ion mobility spectrometry (FAIMS)
enables gas-phase separations on a chromatographic time scale and
has become a useful tool for proteomic applications. Despite its emerging
utility, however, the molecular determinants underlying peptide separation
by FAIMS have not been systematically investigated. Here, we characterize
peptide transmission in a FAIMS device across a broad range of compensation
voltages (CVs) and used machine learning to identify charge state
and three-dimensional (3D) electrostatic peptide potential as major
contributors to peptide intensity at a given CV. We also demonstrate
that the machine learning model can be used to predict optimized CV
values for peptides, which significantly improves parallel reaction
monitoring workflows. Together, these data provide insight into peptide
separation by FAIMS and highlight its utility in targeted proteomic
applications
Supramolecular assembly-derived carbon-nitrogen-based functional materials for photo/electrochemical applications: progress and challenges
Supramolecular chemistry during the synthesis of carbon-nitrogen-based materials has recently experienced a renaissance in the arena of photocatalysis and electrocatalysis. In this review, we start with the discussion of supramolecular assemblies-derived carbon-nitrogen-based materials’ regulation from the aspect of morphology, chemical composition, and micro/nanostructural control. Afterwards the recent advances of these materials in energy and environment related applications, including degradation of pollutants, water splitting, oxygen reduction reactions, CO2 reduction reactions along with organic synthesis are summarized. The correlations between the structural features and physicochemical properties of the carbon-nitrogen-based materials and the specific catalytic activity are discussed in depth. By highlighting the opportunities and challenges of supramolecular assembly strategies, we attempt an outlook on possible future developments for highly efficient carbon-based photo/electrocatalysts.</p
Supramolecular assembly-derived carbon-nitrogen-based functional materials for photo/electrochemical applications: progress and challenges
Supramolecular chemistry during the synthesis of carbon-nitrogen-based materials has recently experienced a renaissance in the arena of photocatalysis and electrocatalysis. In this review, we start with the discussion of supramolecular assemblies-derived carbon-nitrogen-based materials’ regulation from the aspect of morphology, chemical composition, and micro/nanostructural control. Afterwards the recent advances of these materials in energy and environment related applications, including degradation of pollutants, water splitting, oxygen reduction reactions, CO2 reduction reactions along with organic synthesis are summarized. The correlations between the structural features and physicochemical properties of the carbon-nitrogen-based materials and the specific catalytic activity are discussed in depth. By highlighting the opportunities and challenges of supramolecular assembly strategies, we attempt an outlook on possible future developments for highly efficient carbon-based photo/electrocatalysts
Immunity to SARS-CoV-2 up to 15 months after infection
Information concerning the longevity of immunity to SARS-CoV-2 following natural infection may have considerable implications for durability of immunity induced by vaccines. Here, we monitored the SARS-CoV-2 specific immune response in COVID-19 patients followed up to 15 months after symptoms onset. Following a peak at day 15-28 postinfection, the IgG antibody response and plasma neutralizing titers gradually decreased over time but stabilized after 6 months. Compared to G614, plasma neutralizing titers were more than 8-fold lower against variants Beta, Gamma, and Delta. SARS-CoV-2-specific memory B and T cells persisted in the majority of patients up to 15 months although a significant decrease in specific T cells, but not B cells, was observed between 6 and 15 months. Antiviral specific immunity, especially memory B cells in COVID-19 convalescent patients, is long-lasting, but some variants of concern may at least partially escape the neutralizing activity of plasma antibodies