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Through the analysis of the chain failure mode， the main factors that causing the chain elongation is found. Through the validation on the acceleration-fatigue test rig， the chain using vanadinizing pins is more better than carbon-nitrogen and chromizing pins on the chain wear-resistant characteristics. After using vanadinizing pin chain， the problems of the engine project which has the chain severely worn issues is solved. The conclusions and test method has a certain kind of reference on the chain system development and application on the engine.

Ephemeral gully erosion is a significant form of soil erosion that visibly impacts soil productivity and restricts land use. While watersheds are fundamental for controlling soil erosion, past studies have focused on individual ephemeral gully or slope types, which do not fully represent changes in ephemeral gullies at the watershed scale. This research used remote sensing images (0.5 m resolution), unmanned aerial vehicles (UAV), and field investigations to analyze the spatial–temporal evolution and development rate of ephemeral gully erosion at the watershed scale on the Loess Plateau from 2009 to 2021. Using spatial information and morphological parameters of ephemeral gullies obtained from the SegNet model, we found that: (1) ephemeral gully numbers decreased from 4495 in 1999 to 2312 in 2021 due to improved vegetation coverage; (2) average growth rates of ephemeral gully frequency, length, density, dissection degree, and width were 2.87 km−2 year−1, 1.66 m year−1, 0.12 km km−2 year−1, 0.01% year−1, and 0.04 m year−1, respectively; (3) ephemeral gully erosion volume (V) and length (L) had a good power function relationship: V=0.0842L1.1932(R2=0.80). The root‐mean‐square error (RMSE) and coefficient of determination (R2) between measured and predicted ephemeral gully volumes indicated that the V–L relationship has a good predictive ability for ephemeral gully volume; thus, the V–L model was used to evaluate the development rate of ephemeral gully erosion volume in small watersheds from 2009 to 2021, revealing an average value of 743.20 m3 year−1. This study presents an empirical model for assessing ephemeral gully volume and volume changes at a watershed scale using high‐resolution remote sensing images, providing a reference for understanding the development of ephemeral gully erosion in small watersheds over time. [ABSTRACT FROM AUTHOR]

Accurate segmentation of brain gliomas (BG) is a crucial and challenging task for effective treatment planning in BG therapy. This study presents the weight loss function and dropout U‐Net with ConvNeXt block (WD‐UNeXt), which precisely segments BG from few shot MRI. The ConvNeXt block, which comprises the main body of the network, is a structure that can extract more detailed features from images. The weight loss function addresses the issue of category imbalance, thereby enhancing the network's ability to achieve more precise segmentation. The training set of BraTS2019 was used to train the network and apply it to test data. Dice similarity coefficient (DSC), sensitivity (Sen), specificity (Spec) and Hausdorff distance (HD) were used to assess the performance of the method. The experimental results demonstrate that the DSC of whole tumour, tumour core and enhancing tumour reached 0.934, 0.911 and 0.851, respectively. Sen of the sub‐regions achieved 0.922, 0.911 and 0.867. Spec and HD reached 1.000, 1.000, 1.000 and 3.224, 2.990, 2.844, respectively. Compared with the performance of state‐of‐the‐art methods, the DSC and HD of WD‐UNeXt were improved to varying degrees. Therefore, this method has considerable potential for the segmentation of BG. [ABSTRACT FROM AUTHOR]

Early recognition of abnormal gait enables physicians to determine a prompt rehabilitation plan for patients for the most effective treatment and care. The Kinect depth sensor can easily collect skeleton data describing the position of joints in the human body. However, the default human skeleton model of Kinect includes an excessive number of many joints, which limits the accuracy of the gait recognition methods and increases the computational resources required. In this study, we propose an optimized human skeleton model for the Kinect system and streamline the joints using a center-of-mass calculation. We integrate several techniques to propose an end-to-end, spatial–temporal, joint attention graph convolutional network (STJA-GCN) architecture. We conducted experiments with a fivefold cross-validation on two common datasets of information on abnormal gaits to evaluate the performance of the proposed method. The results show that the STJA-GCN achieved 93.17 and 92.08% accuracy on the two datasets, and compared to the original spatial–temporal graph convolutional network (ST-GCN), the recognition accuracy increases by 9.22 and 20.65%, respectively. Overall, the results demonstrate that the STJA-GCN can accurately recognize abnormal gaits and, thus, can support low-cost rehabilitation assessments at community hospitals or in patients' homes. [ABSTRACT FROM AUTHOR]

Non-cytotoxicity or good biocompatibility is an essential requisite for the thermo-sensitive polymeric materials used in the biomedical fields. In this study, a new poly( N-acetyl- L-glutamic acid- co-lysine ester) (PGAL) with excellent thermo-sensitivity and biocompatibility is synthesized from natural lysine and glutamic acid. The chemical structures of the monomers and polymers are determined by H NMR, FTIR spectrum, and GPC. PGAL shows a reversible lower critical solution temperature (LCST) of 17.3-31.7 °C, and the thermo-sensitivity is affected by its molecular weight, structure, and concentration. The viability of HeLa cells in 0.01-10 μg/mL PGAL solution is found to be in a range of 98-110 % after 24, 48, and 72 h of incubation. To sum up, this new thermo-sensitive PGAL has excellent biocompatibility that makes it a promising material in the biomedical fields. [ABSTRACT FROM AUTHOR]

A new thermosensitive poly( N-propionyl-aspartic acid/ethylene glycol) (PPAE) with no cytotoxicity and an upper critical solution temperature (UCST) is synthesized by polycondensation of l-aspartic acid and ethylene glycol. The chemical structures of the monomer and polymer are confirmed by FTIR and 1H NMR spectroscopy, and by elemental analysis measurements. Turbidimetric measurements indicate that PPAE shows a reversible UCST phase transition at 1.5-37.6 °C in pure water or an alcohol/water mixture. The UCST can be facilely tuned via changing the content of alcohol in water or the normal saline. Moreover, the survival rate of HeLa cells to PPAE is close to 100% within 48 h, demonstrating no cytotoxicity. Such aspartic acid-based polymers with tunable thermosensitivity could be useful in the biomedical field. [ABSTRACT FROM AUTHOR]

The ratio of correct diagnosis for primary headache has always been relatively low for general practitioners due to the unacquaintance with headache guideline in Chinese primary hospitals. This study proposed a computerized headache guideline method using SAGE module and developed a decision support system for headache diagnosis, which could be expected to help general practitioners of primary hospitals improve diagnostic accuracy. 282 previously diagnosed cases from EMR were used to evaluate the diagnostic accuracy of the system, the result is: migraine 144/153 (94.1%), tension-type headache 89/100 (89.0%), cluster headache 10/11 (90.9%) and chronic daily headache 53/57(93.0%). The proposed system is in the starting phase of the implementation at the outpatient department of Neurology in Chinese PLA general hospital. [ABSTRACT FROM AUTHOR]