191 research outputs found
High-Throughput Screening of Transition Metal Single-Atom Catalysts for Nitrogen Reduction Reaction
The discovery of metals as catalytic centers for nitrogen reduction reactions
has stimulated great enthusiasm for single-atom catalysts. However, the poor
activity and low selectivity of available SACs are far away from the industrial
requirement. Through the high throughout first principles calculations, the
doping engineering can effectively regulate the NRR performance of b-Sb
monolayer. Especially, the origin of activated N2 is revealed from the
perspective of the electronic structure of the active center. Among the 24
transition metal dopants, Re@Sb and Tc@Sb showed the best NRR catalytic
performance with a low limiting potential. The Re@Sb and Tc@Sb also could
significantly inhibit HER and achieve a high theoretical Faradaic efficiency of
100%. Our findings not only accelerate discovery of catalysts for ammonia
synthesis but also contribute to further elucidate the structure-performance
correlations
Amodal Segmentation Based on Visible Region Segmentation and Shape Prior
Almost all existing amodal segmentation methods make the inferences of
occluded regions by using features corresponding to the whole image. This is
against the human's amodal perception, where human uses the visible part and
the shape prior knowledge of the target to infer the occluded region. To mimic
the behavior of human and solve the ambiguity in the learning, we propose a
framework, it firstly estimates a coarse visible mask and a coarse amodal mask.
Then based on the coarse prediction, our model infers the amodal mask by
concentrating on the visible region and utilizing the shape prior in the
memory. In this way, features corresponding to background and occlusion can be
suppressed for amodal mask estimation. Consequently, the amodal mask would not
be affected by what the occlusion is given the same visible regions. The
leverage of shape prior makes the amodal mask estimation more robust and
reasonable. Our proposed model is evaluated on three datasets. Experiments show
that our proposed model outperforms existing state-of-the-art methods. The
visualization of shape prior indicates that the category-specific feature in
the codebook has certain interpretability.Comment: Accepted by AAAI 202
Reliable Joint Segmentation of Retinal Edema Lesions in OCT Images
Focusing on the complicated pathological features, such as blurred
boundaries, severe scale differences between symptoms, background noise
interference, etc., in the task of retinal edema lesions joint segmentation
from OCT images and enabling the segmentation results more reliable. In this
paper, we propose a novel reliable multi-scale wavelet-enhanced transformer
network, which can provide accurate segmentation results with reliability
assessment. Specifically, aiming at improving the model's ability to learn the
complex pathological features of retinal edema lesions in OCT images, we
develop a novel segmentation backbone that integrates a wavelet-enhanced
feature extractor network and a multi-scale transformer module of our newly
designed. Meanwhile, to make the segmentation results more reliable, a novel
uncertainty segmentation head based on the subjective logical evidential theory
is introduced to generate the final segmentation results with a corresponding
overall uncertainty evaluation score map. We conduct comprehensive experiments
on the public database of AI-Challenge 2018 for retinal edema lesions
segmentation, and the results show that our proposed method achieves better
segmentation accuracy with a high degree of reliability as compared to other
state-of-the-art segmentation approaches. The code will be released on:
https://github.com/LooKing9218/ReliableRESeg
Spatio-temporal characteristics of PM2.5 and O3 synergic pollutions and influence factors in the Yangtze River Delta
Since the implementation of pollution prevention and control action in China in 2013, particulate pollution has been greatly reduced, while ozone pollution has become gradually severe, especially in the economically developed eastern region. Recently, a new situation of air pollution has emerged, namely, enhanced atmospheric oxidation, ascending regional ozone pollution, and increasing particle and ozone synergic pollution (i.e., double-high pollution). Based on the long-term observation data from 2015 to 2021, we examined the spatio-temporal characteristics of urban PM2.5 and O3 pollution in the Yangtze River Delta and quantified the effects of meteorological and non-meteorological factors on pollution in four city clusters using stepwise multiple linear regression models. Temporally, PM2.5 decreased gradually year by year while, O3 increased in city clusters. Spatially, PM2.5 declined from northwest to southeast, while O3 decreased from northeast to southwest. Except for southern Zhejiang, other city clusters suffer from complex air pollution at different levels. In general, pollution intensity and frequency vary with city location and time. Single PM2.5 pollution mostly occurred in northern Anhui. Single O3 pollution occurred in central and southern Jiangsu and northern Zhejiang. Synergic pollutions of PM2.5 and O3 mainly occurred in central Jiangsu. The contributions (90%) of non-meteorological factors (e.g., anthropogenic emission) to PM2.5 decrease and O3 increase are far larger than that of meteorological factors (5%). Relative humidity, sea level pressure, and planetary boundary layer height are the most important meteorological factors to drive PM2.5 changes during pollution. Downward solar radiation, total cloud cover, and precipitation are the most important meteorological factors that affect O3 changes during pollution. The results provide insights into particulate and ozone pollution in the Yangtze River Delta and can help policymakers to formulate accurate air pollution prevention and control strategies at urban and city cluster scales in the future
Comprehending the cuproptosis and cancer-immunity cycle network: delving into the immune landscape and its predictive role in breast cancer immunotherapy responses and clinical endpoints
BackgroundThe role of cuproptosis, a phenomenon associated with tumor metabolism and immunological identification, remains underexplored, particularly in relation to the cancer-immunity cycle (CIC) network. This study aims to rigorously examine the impact of the cuproptosis-CIC nexus on immune reactions and prognostic outcomes in patients with breast cancer (BC), striving to establish a comprehensive prognostic model.MethodsIn the study, we segregated data obtained from TCGA, GEO, and ICGC using CICs retrieved from the TIP database. We constructed a genetic prognostic framework using the LASSO-Cox model, followed by its validation through Cox proportional hazards regression. This framework’s validity was further confirmed with data from ICGC and GEO. Explorations of the tumor microenvironment were carried out through the application of ESTIMATE and CIBERSORT algorithms, as well as machine learning techniques, to identify potential treatment strategies. Single-cell sequencing methods were utilized to delineate the spatial distribution of key genes within the various cell types in the tumor milieu. To explore the critical role of the identified CICs, experiments were conducted focusing on cell survival and migration abilities.ResultsIn our research, we identified a set of 4 crucial cuproptosis-CICs that have a profound impact on patient longevity and their response to immunotherapy. By leveraging these identified CICs, we constructed a predictive model that efficiently estimates patient prognoses. Detailed analyses at the single-cell level showed that the significance of CICs. Experimental approaches, including CCK-8, Transwell, and wound healing assays, revealed that the protein HSPA9 restricts the growth and movement of breast cancer cells. Furthermore, our studies using immunofluorescence techniques demonstrated that suppressing HSPA9 leads to a notable increase in ceramide levels.ConclusionThis research outlines a network of cuproptosis-CICs and constructs a predictive nomogram. Our model holds great promise for healthcare professionals to personalize treatment approaches for individuals with breast cancer. The work provides insights into the complex relationship between the cuproptosis-CIC network and the cancer immune microenvironment, setting the stage for novel approaches to cancer immunotherapy. By focusing on the essential gene HSPA9 within the cancer-immunity cycle, this strategy has the potential to significantly improve the efficacy of treatments against breast cancer
Evolutionary Characterization of the Pandemic H1N1/ 2009 Influenza Virus in Humans Based on Non-Structural Genes
The 2009 influenza pandemic had a tremendous social and economic impact. To study the genetic diversity and evolution of the 2009 H1N1 virus, a mutation network for the non-structural (NS) gene of the virus was constructed. Strains of the 2009 H1N1 pandemic influenza A virus could be divided into two categories based on the V123I mutation in the NS1 gene: G1 (characterized as 123 Val) and G2 (characterized as 123 Ile). Sequence homology analysis indicated that one type of NS sequence, primarily isolated from Mexico, was likely the original type in this pandemic. The two genotypes of the virus presented distinctive clustering features in their geographic distributions. These results provide additional insight into the genetics and evolution of human pandemic influenza H1N1
- …