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Under the fatigue loading condition, tooth flank fracture, crack source initiated at the subsurface position, is a subsurface fatigue failure. The failure mode is closely related to the local material strength and local stress state at the internal points of teeth. Based on the contact theory and elastic mechanics, a mathematical model for calculating the internal field stress of gear teeth with interfacial friction and the stress intensity with hardness gradient was established, and the risk prediction of gear tooth flank fracture was carried out. The results show that the calculated maximum stress risk position occurs at a certain depth below the tooth surface, which is basically consistent with the representative position of the tooth surface fracture fatigue source. With the increase of the friction coefficient, the internal safety factor of the gear teeth decreases, which indicates that poor interfacial lubrication can easily lead to the accelerated initiation of internal cracks in the gear teeth, resulting in the fracture fatigue failure of the tooth surface. The risk prediction model provides basic technical guarantee and support for the design and manufacture of tooth flank fracture resistance.

The development of algorithms for remote sensing of water quality (RSWQ) requires a large amount of in situ data to account for the bio-geo-optical diversity of inland and coastal waters. The GLObal Reflectance community dataset for Imaging and optical sensing of Aquatic environments (GLORIA) includes 7,572 curated hyperspectral remote sensing reflectance measurements at 1 nm intervals within the 350 to 900 nm wavelength range. In addition, at least one co-located water quality measurement of chlorophyll a, total suspended solids, absorption by dissolved substances, and Secchi depth, is provided. The data were contributed by researchers affiliated with 59 institutions worldwide and come from 450 different water bodies, making GLORIA the de-facto state of knowledge of in situ coastal and inland aquatic optical diversity. Each measurement is documented with comprehensive methodological details, allowing users to evaluate fitness-for-purpose, and providing a reference for practitioners planning similar measurements. We provide open and free access to this dataset with the goal of enabling scientific and technological advancement towards operational regional and global RSWQ monitoring.

To investigate evolution of soil arching during suffusion in gap-graded soils, a new suffusion apparatus was developed for trapdoor tests under a horizontal seepage flow. Glass beads with fine-grain contents ranging from 15% to 45% were adopted to represent coarse-grain controlled soils and fine-grain controlled soils. Coupled computational fluid dynamics (CFD) and discrete element method (DEM) models were developed to further investigate the evolution of soil arching from microscopic views. At the early stage of suffusion, soil arching degraded rapidly under seepage loads in both coarse-grain controlled and fine-grain controlled soils due to the compaction of soil skeleton and the clogging of voids, which increased in the number of fine particles connected to the stress-transfer matrix. At the later stage, soil arching was nearly maintained as the soil skeleton became stable in the coarse-grain controlled soils. In the fine-grain controlled soils, soil arching degraded continuously due to continuous loss of fine particles connected to the stress-transfer matrix. The decrease in the contact number of fine particles also made the soil skeleton more vulnerable to suffusion. The degradation of soil arching resulted in an increase of surface displacement and a decrease of soil arching height in fine-grain controlled soils. Key words: soil arching, suffusion, trapdoor test, CFD-DEM, strong force chain, 1. Introduction Soil arching is generally defined as the stress redistribution due to the relative displacement between a yielding soil mass and its adjacent soil masses (Terzaghi 1943). This phenomenon [...]

To investigate the expressions of glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE) and protein S100β and their diagnostic values for sepsis-associated encephalopathy (SAE).

The property of a road base depends on its fine content (FC) and water content/suction. In this study, a cyclic loading test was carried out on road base aggregate with different FCs under controlled suction. The different effects of fines on the accumulated strain of road base aggregate at different FCs and suctions were identified. Under the saturated condition, the accumulated strain increased with FC due to the reduction of soil interparticle friction caused by the inclusion of fines. Under unsaturated conditions, the effect of fines on the accumulated strain depended on the inner structure of the soil. For the 'coarse-graincontrolled soil' (FC in the range of 0%-4%), the accumulated strain increased with the increase of FC due to the reduction of interparticle friction, while for the 'transition soil' (FC in the range of 4%-8%), the accumulated strain decreased with the increase of FC as the major impact of the fines shifted to the enhancement of suction, and the inclusion of fines is beneficial for this case; for the 'fine-grain-controlled soil' (FC in the range of 8%-16%), the accumulated strain increased rapidly with FC as the effect of interparticle friction reduction dominated again. Key words: road base aggregate, fine content, cyclic loading, accumulated strain, unsaturated soil La propriete de la base de la route depend de sa teneur en fines (FC) et de sa teneur en eau/suction. Dans cette etude, l'essai de chargement cyclique a ete effectue sur un agregat de base de route avec differentes teneurs en fines sous des succions controlees. Les differents effets des fines sur la deformation accumulee du granulat de la base de la route a differentes teneurs en fines et suctions ont ete identifies. Dans des conditions de saturation, la deformation accumulee augmente avec la teneur en fines en raison de la reduction de la friction interparticulaire du sol causee par l'inclusion de fines. Dans des conditions non saturees, l'effet des fines sur la deformation accumulee depend de la structure interne du sol. Pour le << sol a gros grains controles (FC dans la gamme de 0-4 %)>>, la deformation accumulee augmente avec l'augmentation de la teneur en fines en raison de la reduction de la friction interparticulaire; tandis que pour le << sol de transition (FC dans la gamme de 4-8%)>>, la deformation accumulee diminue avec l'augmentation de la teneur en fines comme l'impact majeur des fines se deplace vers l'amelioration de la succion, et l'inclusion de fines sera benefique pour ce cas; pour le << sol a grains fins controles (FC dans la gamme de 8-16%)>>, la deformation accumulee augmente rapidement avec la teneur en fines, car l'effet de la reduction de la friction interparticulaire domine a nouveau. [Traduit par la Redaction] Mots-cles : agregat de base de route, teneur en fines, chargement cyclique, deformation accumulee, sol non sature, Introduction Road base aggregates mainly consist of unbound granular materials such as gravel and sand. During a road's service, the road base aggregate can be invaded by fines from particle [...]