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Accurate identification of Seriola dumerili (SD) offers crucial technical support for aquaculture practices and behavioral research of this species. However, the task of discerning S. dumerili from complex underwater settings, fluctuating light conditions, and schools of fish presents a challenge. This paper proposes an intelligent recognition model based on the YOLOv8 network called SD-YOLOv8. By adding a small object detection layer and head, our model has a positive impact on the recognition capabilities for both close and distant instances of S. dumerili, significantly improving them. We construct a convenient S. dumerili dataset and introduce the deformable convolution network v2 (DCNv2) to enhance the information extraction process. Additionally, we employ the bottleneck attention module (BAM) and redesign the spatial pyramid pooling fusion (SPPF) for multidimensional feature extraction and fusion. The Inner-MPDIoU bounding box regression function adjusts the scale factor and evaluates geometric ratios to improve box positioning accuracy. The experimental results show that our SD-YOLOv8 model achieves higher accuracy and average precision, increasing from 89.2% to 93.2% and from 92.2% to 95.7%, respectively. Overall, our model enhances detection accuracy, providing a reliable foundation for the accurate detection of fishes. [ABSTRACT FROM AUTHOR]

This study investigates rhythmic jaw movement (RJM) patterns and masticatory muscle activities during electrical stimulation in two cortical masticatory areas in obese male Zucker rats (OZRs), compared to their counterparts—lean male Zucker rats (LZRs) (seven each). At the age of 10 weeks, electromyographic (EMG) activity of the right anterior digastric muscle (RAD) and masseter muscles, and RJMs were recorded during repetitive intracortical micro-stimulation in the left anterior and posterior parts of the cortical masticatory area (A-area and P-area, respectively). Only P-area-elicited RJMs, which showed a more lateral shift and slower jaw-opening pattern than A-area-elicited RJMs, were affected by obesity. During P-area stimulation, the jaw-opening duration was significantly shorter (p < 0.01) in OZRs (24.3 ms) than LZRs (27.9 ms), the jaw-opening speed was significantly faster (p < 0.05) in OZRs (67.5 mm/s) than LZRs (50.8 mm/s), and the RAD EMG duration was significantly shorter (p < 0.01) in OZRs (5.2 ms) than LZR (6.9 ms). The two groups had no significant difference in the EMG peak-to-peak amplitude and EMG frequency parameters. This study shows that obesity affects the coordinated movement of masticatory components during cortical stimulation. While other factors may be involved, functional change in digastric muscle is partly involved in the mechanism. [ABSTRACT FROM AUTHOR]

In this paper, three key geometrical dimensions such as XL3 (constant pressure mixing chamber length), D5 (diameter of the throat of the ejector), and XL5 (length of the throat of the ejector) were separately or sequentially optimized under different lengths and angles of two sections of the primary nozzle. Furthermore, shock cluster number and shock chain length or area of low static pressure zone were used to analyze the effect of geometries on ejector performance, which is normally indicated by entrainment ratio (ER, or the ratio between the mass flow rate of secondary flow and the mass flow rate of primary flow). The results show that: (1) the improvement of ejector performance with only optimization of the primary nozzle is quite limited, in comparison, the impact of length and angle of nozzle diverging section on ejector performance is higher than that of converging section; (2) the relative sensitivity of ER to three key dimensions is much higher than that to the angles and lengths of the primary nozzle; (3) with the increase of XL3 and D5, ER needs a larger angle and smaller length of nozzle converging section; (4) the impact of key geometries on ejector performance can be analyzed with the help of shock cluster number and shock chain length or area of low static pressure zone. [ABSTRACT FROM AUTHOR]

In this paper, we employ the certain theory of Lie symmetry analysis to discuss the time-fractional Gardner equation with time-dependent coefficients. The Lie point symmetry is applied to realize the symmetry reduction of the equation, and then the power series solutions in some specific cases are obtained. By virtue of the fractional conservation theorem, the conservation laws are constructed. [ABSTRACT FROM AUTHOR]

Large-scale water infrastructure such as immersed tunnels remain in a seawater environment for a long time, and gradually deteriorate under the action of high water head, soil pressure and corrosive ions in seawater solution. In order to simulate the corrosion damage and deterioration of concrete in seawater environment, 10% Na2SO4 solution was used to conduct indoor corrosion tests on concrete samples under different water heads and for different durations. The corrosion damage and micro-mechanical properties of concrete under the coupled action of high water head and sulfate are studied by micro-indentation tests. The effect of sulfate ion corrosion and complex mechanical loading was studied. The effect of micro-mechanical properties of concrete is studied on time and space. Numerical simulation and test results show that the results of micro-indentation are in good agreement with the fitting curves. The chemical damage rate and the corrosion depth increase with the increase of water head; the numerical simulation analysis shows that the sulfate concentration is high in the area where the mechanical damage variable is large, which indicates that the two kinds of corrosion occur in concrete and interact with each other. [ABSTRACT FROM AUTHOR]

The reconstruction of severe alveolar bone defects remains a complex and challenging field for clinicians. Three-dimensional-printed scaffolds can adapt precisely to the complicated shape of the bone defects, which is an alternative solution to bone tissue engineering. Our previous study constructed an innovative low-temperature 3D-printed silk fibroin/collagen I/nano-hydroxyapatite (SF/COL-I/nHA) composite scaffold with a stable structure and remarkable biocompatibility. However, the clinical translation of most scaffolds is limited by insufficient angiogenesis and osteogenesis. In this study, we investigated the effects of human umbilical cord mesenchymal-stem-cell-derived exosomes (hUCMSC-Exos) on bone regeneration, especially from the perspective of inducing angiogenesis. HUCMSC-Exos were isolated and characterized. In vitro, the effect of hUCMSC-Exos on the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) was examined. Moreover, the loading and release of hUCMSC-Exos on 3D-printed SF/COL-I/nHA scaffolds were evaluated. In vivo, hUCMSC-Exos and 3D-printed SF/COL-I/nHA scaffolds were implanted into alveolar bone defects, and bone regeneration and angiogenesis were investigated by micro-CT, HE staining, Masson staining, and immunohistochemical analysis. The results showed that hUCMSC-Exos stimulated HUVEC proliferation, migration, and tube formation in vitro, and the effect increased with increasing exosome concentrations. In vivo, the combination of hUCMSC-Exos and 3D-printed SF/COL-I/nHA scaffolds promoted alveolar bone defect repair by enhancing angiogenesis and osteogenesis. We constructed an elaborate cell-free bone-tissue-engineering system by combining hUCMSC-Exos with 3D-printed SF/COL-I/nHA scaffolds, potentially providing new ideas for treating alveolar bone defects. [ABSTRACT FROM AUTHOR]

The grain number per spike (GNPS) is an important yield component, and much attention is given to the increase in GNPS for current yield improvement of common wheat. Here, a panel of 259 pre-breeding lines and elite commercial varieties were collected for the investigation of 12 agronomic traits, especially for spike-related traits, with 2-year replicates. The high correlation between GNPS and kernel number per spikelet (KNS) suggested that the high GNPS trait in our pre-breeding lines was mainly controlled by grain set number per spikelet. Genome-wide association studies (GWAS) using the 660K SNP genotyping assay suggested that a major locus on chromosomes 4BS contributed to the high GNPS trait, which contributed to 33% and 48% of the variation in KNS and GNPS, respectively. A good diagnostic KASP marker AX-109286577 flanking the 4BS locus was developed for easy selection of the large spike trait. Taken together, the results suggested that untapped rare allele variation in our pre-breeding lines can be used for improvement of the yield component of set grain number per spike. [ABSTRACT FROM AUTHOR]