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1.
Sensors (Basel) ; 24(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39001112

RESUMO

A robust wood material crack detection algorithm, sensitive to small targets, is indispensable for production and building protection. However, the precise identification and localization of cracks in wooden materials present challenges owing to significant scale variations among cracks and the irregular quality of existing data. In response, we propose a crack detection algorithm tailored to wooden materials, leveraging advancements in the YOLOv8 model, named ICDW-YOLO (improved crack detection for wooden material-YOLO). The ICDW-YOLO model introduces novel designs for the neck network and layer structure, along with an anchor algorithm, which features a dual-layer attention mechanism and dynamic gradient gain characteristics to optimize and enhance the original model. Initially, a new layer structure was crafted using GSConv and GS bottleneck, improving the model's recognition accuracy by maximizing the preservation of hidden channel connections. Subsequently, enhancements to the network are achieved through the gather-distribute mechanism, aimed at augmenting the fusion capability of multi-scale features and introducing a higher-resolution input layer to enhance small target recognition. Empirical results obtained from a customized wooden material crack detection dataset demonstrate the efficacy of the proposed ICDW-YOLO algorithm in effectively detecting targets. Without significant augmentation in model complexity, the mAP50-95 metric attains 79.018%, marking a 1.869% improvement over YOLOv8. Further validation of our algorithm's effectiveness is conducted through experiments on fire and smoke detection datasets, aerial remote sensing image datasets, and the coco128 dataset. The results showcase that ICDW-YOLO achieves a mAP50 of 69.226% and a mAP50-95 of 44.210%, indicating robust generalization and competitiveness vis-à-vis state-of-the-art detectors.

2.
Molecules ; 28(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37175058

RESUMO

Cutting fluids are the most effective method to lower the cutting temperature and decrease the cutting tool wear. At the same time, the cutting fluids influence the corrosion resistance property of the machined surface. In this study, chlorinated paraffin (CP), which is a common additive in the cutting fluid, was selected as the research objective to study its corrosion resistance property. The passivation effect of CP with different concentrations on the machined surface of stainless steel was studied. Electrochemical measurements and surface morphology investigation were used to characterize the passivation effect of CP with different concentrations. The test results showed that the corrosion resistance of stainless steel in the cutting fluid was enhanced with the increase in CP additive. This reason is that the charge transfer resistance increases and the corrosion current density decreases with the increase in CP additive. The X-ray photoelectron spectroscopy (XPS) results show that the proportion of metal oxides on the processed surface of the stainless steel sample was increased from 20.4% to 22.0%, 32.9%, 26.6%, and 31.1% after adding 1 mL, 2 mL, 4 mL and 6 mL CP in the cutting fluid with a total volume of 500 mL, respectively. The oxidation reaction between CP and the stainless steel sample resulted in an increase in metal oxides proportion, which prevented the stainless steel sample from corrosion in cutting fluid.

3.
J Phys Condens Matter ; 34(44)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35985306

RESUMO

Cluster is the intermediate of individual atom and larger agglomeration. The structural evolutions of clusters are critically important to explore the physical properties of bulk solids. Here, we carry out systematic structure predictions of medium-sized vanadium-doped boron clusters by using crystal structure analysis by particle swarm optimization method combined with density function theory calculations. A great deal of low-lying isomers with attractive geometries are discovered, such as the crown-like VB18-cluster and the drum-like VB20-cluster. Interestingly, the VB12-cluster possesses excellently relative stability due to its higher second-order difference and larger highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap. The molecular orbitals (MOs) and adaptive natural density partitioning (AdNDP) analysis indicate that the 3dorbitals of V atom and the 2pand 2sorbitals of B atoms are the primary constituents of the MOs, and the interactions between V and B atoms are the main factor for the robust stabilization of the anionic VB12-cluster. The present findings advance the understanding of the structural evolution of transition metal doped boron clusters and offer crucial insights for future experiments.

4.
Phytother Res ; 35(7): 3848-3860, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33792992

RESUMO

Random skin flap is widely used in plastic surgery. However, flap necrosis caused by ischemia-reperfusion injury limits its clinical applications. Apigenin, a naturally occurring flavonoid mainly derived from plants, facilitates flap survival. In this study, we explored the effects of apigenin on flap survival and the underlying mechanisms. A total of 54 mice having a dorsal random flap model were randomly divided into control, apigenin, and apigenin +3-methyladenine groups. These groups were treated with dimethyl sulfoxide solution, apigenin, and apigenin +3-methyladenine, respectively. The animals were then euthanized to assess angiogenesis, apoptosis, oxidative stress, and autophagy levels through histological and protein analyses. Apigenin promotes survival of the skin flap area and reduces tissue edema. In addition, apigenin enhanced angiogenesis, attenuated apoptosis, alleviated oxidative stress, and activated autophagy. Interestingly, 3-methyladenine reversed the effects of apigenin on flap survival, angiogenesis, apoptosis, and oxidative stress through inhibition of autophagy. The findings of this study show that apigenin promotes angiogenesis, inhibits cell apoptosis, and lowers oxidative stress by mediating autophagy, thus the improving survival rate of random skin flaps.


Assuntos
Apigenina , Autofagia , Sobrevivência de Enxerto/efeitos dos fármacos , Pele , Retalhos Cirúrgicos , Indutores da Angiogênese , Animais , Apigenina/farmacologia , Apoptose/efeitos dos fármacos , Camundongos , Estresse Oxidativo , Pele/metabolismo
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