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The concept of granular void ratio, in which the volume of fines is treated as voids, was introduced to characterise mixed soils that contain both coarse (sand-size and above) and fine (clay and silt-size) soil particles. In using this concept, fines are assumed to make no contribution to the mechanical properties of the mixed soil. In this paper, this assumption is assessed through the analyses of a number of published results as well as data from tests conducted specifically for this study. The assessment shows that, in most instances, the relation between undrained shear strength and granular void ratio of the mixed soil is not the same as that of the host coarse material. At the same granular void ratio plastic fines generally cause a reduction in undrained strength and, at best, act like voids, whereas non-plastic fines increase the undrained strength and, at worst, act like voids. A recently introduced equivalent granular void ratio, which makes use of a modification factor b to account for the contribution of fines, was evaluated. The equivalent granular void ratio was found to be able to synthesise the various results. The factor b has a different range of values, depending on the hardness of the fines, and reflecting the different ways these fines contribute to the behaviour. For non-plastic and thus relatively harder fines, b depends on the ratio of the average size of the fines to the average pore size space of the host coarse material. For plastic fines, this factor depends on the pore space of the host coarse material and the stress history, such as the overconsolidation ratio.Le concept de taux de pore granulaire, dans lequel le volume de fines est traité en tant que vide, a été introduit pour caractériser les sols mélangés qui contiennent à la fois de grosses particules (de la taille du sable et audessus) et des fines (de la taille de l'argile et du limon). En utilisant ce concept, nous présupposons que les fines ne font aucune contribution aux propriétés mécaniques du sol mélangé. Dans cet exposé, nous évaluons cette supposition en analysant un certain nombre de résultats publiés ainsi que les résultats d'essais conduits spécifiquement pour cette étude. L'évaluation montre que, dans la plupart des cas, la relation entre résistance au cisaillement non drainé et taux de pore granulaire du sol mélangé n'est pas la même que celle de la matière hôte grossière. Pour le même taux de pore granulaire, les fines plastiques provoquent généralement une réduction de la résistance non drainée et, au mieux, agissent comme des vides, alors que les fines non plastiques augmentent la résistance non drainée et, au pire, agissent comme des vides. Nous avons évalué un taux de pore granulaire équivalent, récemment introduit, qui utilise un facteur de modification b pour représenter la contribution des fines. Nous avons trouvé que le taux de pore granulaire équivalent était capable de synthétiser les divers résultats. Le facteur b a une gamme de valeurs différente selon la dureté des fines et réfléchis-sant les diverses...

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A small-scale physical modelling method was developed to study the movement of clay during pile installation. The clay was simulated using a mixture of amorphous silica and mineral oil, which becomes almost transparent when the refractive indices of the oil and the silica are well matched. After adding reflective particles and consolidating the mixture in a transparent container, cylindrical model piles were driven vertically at the centre. A vertical section aligned with the pile centreline was illuminated by a laser light sheet, and a sequence of digital images was recorded. These were analysed using particle image velocimetry, and the complete displacement distribution during the pile installation was obtained. Notwithstanding some discrepancies at shallow depths, the observed displacements generally showed fairly good agreement with the theoretical predictions of the shallow strain path method (SSPM) once the effect of some soil trapped beneath the flat pile tip was taken into account. Normalisation of the horizontal and vertical components of movement employing both the pile length and radius, based on SSPM theory, was shown to be valid. The normalised vertical displacement contours were similar to those published by previous researchers. The results of this study could be used to assess the impact of disturbance due to pile installation on, for example, buried services or archaeology.

Osteosarcoma is among the most common malignant bone tumors in human skeletal system. The conventional treatment of osteosarcoma mainly consists of combining neoadjuvant chemotherapy with surgical approach. However, it is crucial to design an artificial implant that possesses excellent biomechanical properties and is capable of sustaining local release of chemotherapeutics. In this study, we envision that the highly efficient combination of gemcitabine (GEM) hydrochloride loaded liposomes with gelatin methacryloyl (GelMA) of in situ photocrosslinkable hydrogel will lead to a multifunctional implant with unique antitumor, mechanical, and biodegradable properties. A sustained controlled release was observed; more specifically, the release of GEM in vitro lasted for 4 days long. Furthermore, its capability in killing MG63 cells was further explored by using the lixivium of GEM-Lip@Gel and GEM-GelMA hydrogel in vitro (composite hydrogel by GEM loaded liposomes blending with GelMA, short for GEM-Lip@Gel), which agreed with the drug release outcome. In addition, these hydrogel showed excellent ability in inhibiting osteosarcoma in vivo by Balb/c mice bearing MG63 cells. Therefore, GEM-loaded lipo-hydrogel certainly has presented itself as a promising strategy for the development of implant in the field of osteosarcoma treatment.

Psychological disorders are associated with increased risk of severe inflammatory bowel disease (IBD) by causing gut microbiota dysbiosis and colonic mucosal barrier damage. However, the interaction between chronic restraint stress (CRS), gut microbiota composition, and colonic mucus remains unclear. We demonstrated that mice under CRS conditions exhibited alterations in microbiota composition, disruption of colonic mucus, and aggravation of colitis. In addition, the abundance of Akkermansia muciniphila was significantly decreased in mice under CRS and UC patients with depression, and positively associated with the expression of MUC2. After antibiotic treatment, the recipient mice colonized with CRS microbiota showed barrier defects and severe colitis. Administration of Akkermansia muciniphila was found to restore colonic mucus and modify the gut microbiota. We confirm that CRS-mediated gut microbiota dysbiosis results in colonic mucosal barrier damage and aggravation of colitis. Our results suggest that A. muciniphila is expected to be a potential probiotic to protect and treat colonic mucus that is involved in IBD with psychological disorders.