As a biological characteristic, gait uses the posture characteristics of human walking for identification, which has the advantages of a long recognition distance and no requirement for the ...cooperation of subjects. This paper proposes a research method for recognising gait images at the frame level, even in cases of discontinuity, based on human keypoint extraction. In order to reduce the dependence of the network on the temporal characteristics of the image sequence during the training process, a discontinuous frame screening module is added to the front end of the gait feature extraction network, to restrict the image information input to the network. Gait feature extraction adds a cross-stage partial connection (CSP) structure to the spatial–temporal graph convolutional networks’ bottleneck structure in the ResGCN network, to effectively filter interference information. It also inserts XBNBlock, on the basis of the CSP structure, to reduce estimation caused by network layer deepening and small-batch-size training. The experimental results of our model on the gait dataset CASIA-B achieve an average recognition accuracy of 79.5%. The proposed method can also achieve 78.1% accuracy on the CASIA-B sample, after training with a limited number of image frames, which means that the model is more robust.
•An adaptive-stacking algorithm based on Google Earth Engine was proposed.•LandTrendr was utilized to analyze vegetation dynamics of wetland.•The recovery condition of the wetland vegetation around ...Dongting Lake was good.
Wetland vegetation is susceptible to climate change and human disturbance, and has experienced significant losses and degradation. However, the spatial patterns of dynamics for China’s inland lake wetlands remain unknown. In this paper, an adaptive-stacking algorithm based on Google Earth Engine was proposed to map the vegetation distribution of Dongting Lake wetland using Sentinel-1/2 and DEM data. Subsequently, LandTrendr was utilized to analyze vegetation dynamics over the 1999–2018 based on Landsat normalized combustion ratio time-series. By overlaying the latest vegetation types and spatial distribution of vegetation dynamics, the main types of vegetation change were examined. Results showed that the overall accuracy and kappa coefficient of adaptive-stacking classification were 94.59% and 0.92, respectively, which were higher than those of support vector machine and random forest. The overall accuracy of change detection for three types (vegetation gain, vegetation loss, and no changes) was 83.67%. In the past 20 years, 2,604.43 and 5,458.84 km2 land has experienced vegetation loss and gain, respectively. The increase in the areas of forest, reed, and sedge in wetland were 1330.39, 86.42, 136.97 km2, respectively. We found that the overall recovery condition of the wetland vegetation around Dongting Lake was good, which demonstrated the key role played by the national wetland ecological protection policy.
Present photocatalysts for the synchronous cleanup of pharmaceuticals and heavy metals have several drawbacks, including inadequate reactive sites, inefficient electron–hole disassociation, and ...insufficient oxidation and reduction power. In this research, we sought to address these issues by using a facile solvothermal-photoreduction route to develop an innovative plasmonic S-scheme heterojunction, Au/MIL-101(Fe)/BiOBr. The screened-out Au/MIL-101(Fe)/BiOBr (AMB-2) works in a durable and high-performance manner for both Cr(VI) and norfloxacin (NOR) eradication under visible light, manifesting up to 53.3 and 2 times greater Cr(VI) and NOR abatement rates, respectively, than BiOBr. Remarkably, AMB-2's ability to remove Cr(VI) in a Cr(VI)-NOR co-existence system is appreciably better than in a sole-Cr(VI) environment; the synergy among Cr(VI), NOR, and AMB-2 results in the better utilization of photo-induced carriers, yielding a desirable capacity for decontaminating Cr(VI) and NOR synchronously. The integration of MOF-based S-scheme heterojunctions and a plasmonic effect contributes to markedly reinforced photocatalytic ability by increasing the number of active sites, augmenting the visible-light absorbance, boosting the efficient disassociation and redistribution of powerful photo-carriers, and elevating the generation of reactive substances. We provide details of the photocatalytic mechanism, NOR decomposition process, and bio-toxicity of the intermediates. This synergistic strategy of modifying S-scheme heterojunctions with a noble metal opens new horizons for devising excellent MOF-based photosystems with a plasmonic effect for environment purification.
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•A novel plasmonic MOF-based S-scheme heterostructure of Au/MIL-101(Fe)/BiOBr was devised.•Au/MIL-101(Fe)/BiOBr exhibited high photo-activity for the eradication of Cr(VI) and norfloxacin.•Au/MIL-101(Fe)/BiOBr worked more effectively in a Cr(VI)-NOR coexistence system.•The photocatalysis mechanism, antibiotic degradation pathways, and toxicities were analyzed.•Integrating MOF-based S-scheme heterojunctions and a plasmonic effect contributed to the reinforced photo-activity.
Crustaceans (e.g., shrimp and crabs) are a good source of protein-rich foods for human consumption. They are the second largest aquaculture species worldwide. Understanding the digestion of dietary ...protein, as well as the absorption, metabolism and functions of amino acids (AAs) and small peptides is essential to produce cost-effective and sustainable aquafeeds. Hepatopancreas (the midgut gland) is the main site for the digestion of dietary protein as well as the absorption of small peptides and AAs into the hemolymph. Besides serving as the building blocks of protein, AAs (particularly aspartate, glutamate, glutamine and alanine) are the primary metabolic fuels for the gut and extra-hepatopancreas tissues (e.g., kidneys and skeletal muscle) of crustaceans. In addition, AAs are precursors for the syntheses of glucose, lipids, H
S, and low-molecular-weight molecules (e.g., nitric oxide, glutathione, polyamines, histamine, and hormones) with enormous biological importance, such as physical barrier, immunological and antioxidant defenses. Therefore, both nutritionally essential and nonessential AAs are needed in diets to improve the growth, development, molt rate, survival, and reproduction of crustaceans. There are technical difficulties and challenges in the use of crystalline AAs for research and practical production due to the loss of free AAs during feed processing, the leaching of in-feed free AAs to the surrounding water environment, and asynchronous absorption with peptide-bounded AAs. At present, much knowledge about AA metabolism and functions in crustaceans is based on studies of mammals and fish species. Basic research in this area is necessary to lay a solid foundation for improving the balances and bioavailability of AAs in the diets for optimum growth, health and wellbeing of crustaceans, while preventing and treating their metabolic diseases. This review highlights recent advances in AA nutrition and metabolism in aquatic crustacean species at their different life stages. The new knowledge is expected to guide the development of the next generation of their improved diets.
Partially oxidizing methane into syngas via a two-step chemical looping scheme is a promising option for methane transformation. Providing the optimum lattice oxygen to selectively produce syngas ...represents the major challenge for the development of oxygen carrier materials in chemical looping processes. This paper describes the design of WO3-based oxygen carriers as the primary source of lattice oxygen with high melting points and attractive syngas selectivity. To further enhance the lattice oxygen availability and methane conversion capacity, NiO nanoclusters are introduced, considering the doping effect on chemical bonding disruption in both bulk and surface regions. For Ni0.5WO x /Al2O3, the nickel cations incorporated into the bulk of WO3 can strongly weaken the tungsten–oxygen bond strength and increase the availability of lattice oxygen. The surface-grafted nickel species can effectively activate methane molecules and catalyze the partial oxidation reaction. Total methane conversion and syngas yield can be substantially increased by about 2.7-fold in comparison with unmodified WO3/Al2O3. This work demonstrates that the bulk and surface modifications are feasible to tailor the active lattice oxygen of oxygen-carrying materials in chemical looping processes.
•We propose a three-stage diagnosis method of rotating machinery towards imbalanced data.•A novel synthetic oversampling approach is proposed.•An enhanced deep auto-encoder is developed to learn ...sparse robust features.•The proposed method is validated on 25 benchmark imbalanced datasets and a real engineering application.
Imbalanced data problems are prevalent in the real rotating machinery applications. Traditional data-driven diagnosis methods fail to identify the fault condition effectively for lack of enough fault samples. Therefore, this study proposes an effective three-stage fault diagnosis method towards imbalanced data. First, a new synthetic oversampling approach called weighted minority oversampling (WMO) is devised to balance the data distribution. It adopts a new data synthesis strategy to avoid generating incorrect or unnecessary samples. Second, to select useful features automatically, an enhanced deep auto-encoder (DA) approach is adopted. DA is improved in two aspects: 1) a new cost function based on maximum correntropy and sparse penalty is designed to learn sparse robust features; 2) a fine-tuning operation with a self-adaptive learning rate is developed to ensure the good convergence performance. Finally, the C4.5 decision tree identifies the learned features. The proposed method named WMODA is evaluated on 25 benchmark imbalanced datasets. It achieves better results than five well-known imbalanced data learning methods. It is also evaluated on a real engineering dataset. The experimental results show that WMODA can detect more fault samples than the traditional data-driven methods.
ABSTRACT We explore the interaction between Hall waves and mechanical failures inside a magnetar crust, using detailed one-dimensional models that consider temperature-sensitive plastic flow, heat ...transport, and cooling by neutrino emission, as well as the coupling of the crustal motion to the magnetosphere. We find that the dynamics is enriched and accelerated by the fast, short-wavelength Hall waves that are emitted by each failure. The waves propagate and cause failures elsewhere, triggering avalanches. We argue that these avalanches are the likely sources of outbursts in transient magnetars.
The success of targeted drug therapy for cancer patients has attracted extensive attention from academia and society. However, the rapid development of acquired drug resistance is becoming a major ...challenge. Autophagy, as an essential homeostatic and catabolic process, is crucial for the degradation or recycling of proteins and cellular components. Autophagy has a crucial role in several cellular functions and its dysregulation is associated with tumorigenesis, tumor–stroma interactions, and resistance to cancer therapy. A growing body of evidence shows that in multiple types of cancer, autophagy is also a key regulator in the tumor microenvironment and the cellular drug response. However, our understanding of the process of autophagy remains incompletely. In this review, we identify the role of autophagy and describe recent advances in the identification of the mechanism by which autophagy is implicated in drug resistance, with a focus on the mode of action, and validation as potential therapeutics.
Soil microbial community composition and litter quality are important drivers of litter decomposition, but how litter quality influences the soil microbial composition largely remains unknown. We ...conducted a microcosm experiment to examine the effects of changes in litter quality induced by long-term N deposition on soil microbial community composition. Mixed-species litter and single-species litter were collected from a field experiment with replicate plots exposed to long-term N-addition in a semiarid grassland in northern China. The litters were decomposed in a standard live soil after which the composition of the microbial community was determined by Illumina MiSeq Sequencing. Changes in litter stoichiometry induced by N-addition increased the diversity of the fungal community. The alpha-diversity of the fungal community was more sensitive to the type of litter (mixed- or single-species) than to the N-addition effects, with higher abundance of fungal OTUs and Shannon-diversity observed in soil with mixed-species litter. Moreover, the relative abundance of saprophytic fungi increased with increasing N-addition rates, which suggests that fungi play an important role in the initial stages of the decomposition process. Litter type and N addition did not significantly change the diversity of bacterial community. The relative abundance of ammonia-oxidizing bacteria was lower in high N-addition treatments than in those with lower N input, indicating that changes in litter stoichiometry could change ecosystem functioning via its effects on bacteria. Our results presented robust evidence for the plant-mediated pathways through which N-deposition affects the soil microbial community and biogeochemical cycling.
•Changes in litter quality increased the diversity of fungal community.•Higher fungal diversity was observed in soil with mixed litter.•Saprophytic fungi increased with increasing N-addition rates.•Ammonia-oxidizing bacteria was lower in high N-addition treatments.
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