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An experimental study was carried out to investigate the effects of soil partial saturation on the behaviour of laterally loaded piles. The proposed study was conducted by means of centrifuge tests at 100g, where a single vertical pile was subjected to a combination of static horizontal load and bending moment. The study was conducted on a silty soil characterized with laboratory testing under saturated and unsaturated conditions. During flight, two different positions of water table were explored. The influence of density was investigated by compacting the sample with two different void ratios. Finally, the effects of a variation of saturation degree on the pile response under loading were studied by raising the water table to the ground surface. Data interpretation allows drawing different considerations on the effects of partial saturation on the behaviour of laterally loaded piles. As expected, compared to saturated soils, partial saturation always leads to a stiffer and resistant response of the system. However, the depth of the maximum bending moment is related to the position of the water table and the bounding effects induced by partial saturation appear to be more important for loose soils. Key words: centrifuge modelling, unsaturated soils, soil-structure interaction, piles, lateral loading. Une etude experimentale a ete realisee pour etudier les effets de la saturation partielle du sol sur le comportement de pieux charges lateralement. L'etude proposee a ete realisee au moyen d'essais en centrifugeuse a 100 g, au cours desquels un seul pieu vertical a ete soumis a une combinaison de charge horizontale statique et de moment de flexion. L'etude a ete menee sur un sol limoneux caracterise par des essais en laboratoire dans des conditions saturees et non saturees. En vol, deux positions differentes de la nappe phreatique ont ete explorees. L'influence de la densite a ete etudiee en compactant l'echantillon a deux indices des vides differents. Enfin, les effets d'une variation du degre de saturation sur la reponse du pieu sous chargement ont ete etudies lors de l'elevation de la nappe phreatique jusqu'a la surface du sol. L'interpretation des donnees permet de tirer differentes considerations sur les effets de la saturation partielle sur le comportement des pieux chargees lateralement. Comme prevu, par rapport aux sols satures, une saturation partielle conduit toujours a une reponse plus rigide et resistante du systeme. Cependant, la profondeur du moment de flexion maximal est liee a la position de la nappe phreatique et les effets de liaison induits par la saturation partielle semblent etre plus importants pour les sols meubles. [Traduit par la Redaction] Mots-cles : modelisation centrifuge, sols non satures, interaction sol-structure, pieux, chargement lateral., Introduction The significant soil volume interested by the kinematics of piles foundation under lateral loading is typically limited vertically in the first metres (several diameters of pile) of depth from [...]

Ref.: Can. Geotech. J. 49(9): 1102-1114 (2012) dx.doi.org/10.1139/t2012-064. Replace Fig. 5 with the figure shown herein, where the unit shown in the label on the vertical axis 'N/m' has been [...]

In this paper, selected aspects of an experimental study conducted in a geotechnical centrifuge are discussed. The tests aimed to explore the effects of partial saturation of soil on the response of a single pile subjected to a combination of lateral force and bending moment under drained conditions. The soil used in the experiments is a low plasticity silty soil, named B-grade kaolin, characterized by a relatively high permeability compared to the typical values for clayey soils. Two different elevations of the water table and its effects on the pile response under loading are studied. The data show a marked influence of soil partial saturation on the pile response, both under working loads and ultimate loads. In particular, under working loads, the displacement of the head of the pile is appreciably lower than that measured under saturated conditions.

The climatic chamber at the Universidad de Los Andes was improved for modeling desiccation in soil layers. This chamber allows the measurement of different environmental variables. In this research, evaporation tests were conducted in water imposing boundary conditions for drying, and then these tests were performed in a soil layer. The soil was prepared from a slurry state and was drying controlling the temperature, the infrared radiation, the wind velocity, and the relative humidity. In the first part of this paper, a description of the climatic chamber, operation ranges and theoretical work principles of the climatic chamber are presented. Then, the second part shows the results for desiccation in water and soil. The desiccation tests performed with the climatic chamber allow simulating all environmental conditions accurately during drying coupling the effect of all environmental variables. As a result, the evaporation rate increases with infrared radiation in soil and water. The rate at the beginning of the desiccation tests in clays is the same as in water. However, this evaporation rate decreases as the soil becomes desiccated.

Over the past decade, the emergence of patient-derived tumor organoids (PDTOs) has broadened the repertoire of preclinical models and progressively revolutionized three-dimensional cell culture in oncology. PDTO can be grown from patient tumor samples with high efficiency and faithfully recapitulates the histological and molecular characteristics of the original tumor. Therefore, PDTOs can serve as invaluable tools in oncology research, and their translation to clinical practice is exciting for the future of precision medicine in oncology. In this review, we provide an overview of methods for establishing PDTOs and their various applications in cancer research, starting with basic research and ending with the identification of new targets and preclinical validation of new anticancer compounds and precision medicine. Finally, we highlight the challenges associated with the clinical implementation of PDTO, such as its representativeness, success rate, assay speed, and lack of a tumor microenvironment. Technological developments and autologous cocultures of PDTOs and stromal cells are currently ongoing to meet these challenges and optimally exploit the full potential of these models. The use of PDTOs as standard tools in clinical oncology could lead to a new era of precision oncology in the coming decade., (© 2024. The Author(s).)

Background: Ovarian cancer is the first cause of death from gynecological malignancies mainly due to development of chemoresistance. Despite the emergence of PARP inhibitors, which have revolutionized the therapeutic management of some of these ovarian cancers, the 5-year overall survival rate remains around 45%. Therefore, it is crucial to develop new therapeutic strategies, to identify predictive biomarkers and to predict the response to treatments. In this context, functional assays based on patient-derived tumor models could constitute helpful and relevant tools for identifying efficient therapies or to guide clinical decision making., Method: The OVAREX study is a single-center non-interventional study which aims at investigating the feasibility of establishing in vivo and ex vivo models and testing ex vivo models to predict clinical response of ovarian cancer patients. Patient-Derived Xenografts (PDX) will be established from tumor fragments engrafted subcutaneously into immunocompromised mice. Explants will be generated by slicing tumor tissues and Ascites-Derived Spheroids (ADS) will be isolated following filtration of ascites. Patient-derived tumor organoids (PDTO) will be established after dissociation of tumor tissues or ADS, cell embedding into extracellular matrix and culture in specific medium. Molecular and histological characterizations will be performed to compare tumor of origin and paired models. Response of ex vivo tumor-derived models to conventional chemotherapy and PARP inhibitors will be assessed and compared to results of companion diagnostic test and/or to the patient's response to evaluate their predictive value., Discussion: This clinical study aims at generating PDX and ex vivo models (PDTO, ADS, and explants) from tumors or ascites of ovarian cancer patients who will undergo surgical procedure or paracentesis. We aim at demonstrating the predictive value of ex vivo models for their potential use in routine clinical practice as part of precision medicine, as well as establishing a collection of relevant ovarian cancer models that will be useful for the evaluation of future innovative therapies., Trial Registration: The clinical trial has been validated by local research ethic committee on January 25th 2019 and registered at ClinicalTrials.gov with the identifier NCT03831230 on January 28th 2019, last amendment v4 accepted on July 18, 2023., (© 2024. The Author(s).)

Background: In the era of personalized medicine, the establishment of preclinical models of cancer that faithfully recapitulate original tumors is essential to potentially guide clinical decisions., Methods: We established 7 models [4 cell lines, 2 Patient-Derived Tumor Organoids (PDTO) and 1 Patient-Derived Xenograft (PDX)], all derived from the same Ovarian Clear Cell Carcinoma (OCCC). To determine the relevance of each of these models, comprehensive characterization was performed based on morphological, histological, and transcriptomic analyses as well as on the evaluation of their response to the treatments received by the patient. These results were compared to the clinical data., Results: Only the PDX and PDTO models derived from the patient tumor were able to recapitulate the patient tumor heterogeneity. The patient was refractory to carboplatin, doxorubicin and gemcitabine, while tumor cell lines were sensitive to these treatments. In contrast, PDX and PDTO models displayed resistance to the 3 drugs. The transcriptomic analysis was consistent with these results since the models recapitulating faithfully the clinical response grouped together away from the other classical 2D cell culture models. We next investigated the potential of drugs that have not been used in the patient clinical management and we identified the HDAC inhibitor belinostat as a potential effective treatment based on PDTO response., Conclusions: PDX and PDTO appear to be the most relevant models, but only PDTO seem to present all the necessary prerequisites for predictive purposes and could constitute relevant tools for therapeutic decision support in the context of these particularly aggressive cancers refractory to conventional treatments., (© 2023. Italian National Cancer Institute ‘Regina Elena’.)

Review of literature shows that it is possible to establish tumor-derived organoids, or tumoroids, from almost any type of tumor, and that these "micro-tumors" could be used to develop functional assays allowing the prediction of the patient response to treatments and/or the identification of predictive molecular signatures associated with the development of these therapies. Although it is still essential to optimize culture conditions to promote and accelerate the establishment of tumoroids, or to recapitulate tumor microenvironment, many applications are now possible in the field of prediction of response to treatments and in guiding therapeutic decision-making. Using tumoroids as standard tools in clinical oncology could make precision oncology enter a new era in the coming decade. Numerous ongoing research and clinical trials conducted throughout the world aim to validate the interest of this approach., (© 2022 médecine/sciences – Inserm.)

The recent emergence of tumor organoid cultures, or tumoroids, has enriched the repertoire of preclinical models in oncology. These microtumors are obtained in vitro by including cells from patient tumor samples in an extracellular matrix and cultured in specific media. Very close to the tumor of origin, tumoroids can be amplified fairly rapidly from a small quantity of tissue, established with high success rate for most tumor types, easily genetically engineered, and stored in biobanks. Tumoroids thus offer numerous possibilities in terms of basic research, such as the study of carcinogenesis or mechanisms of chemoresistance, but also the identification of new targets and preclinical validation of new anti-cancer compounds or personalized medicine. Technological developments and enrichment of tumoroids with other cell types are currently ongoing to optimally exploit the full potential of these models., (© 2022 médecine/sciences – Inserm.)

The presented dataset was collected in seven centrifuge tests, specifically designed for modelling the lateral response of offshore monopiles in dense sand. Two model piles with outer diameter D  = 50 mm were loaded laterally at 100 ×  g . The embedding depths were 3 D , 5 D , 7 D and 9 D , with load eccentricity of 5, 10 and 15. Fibre Bragg gratings (FBGs) were used to measure the tensile and compressive strains of the monopiles. The raw data obtained from different sensors during the tests and the analysed data (e.g. soil reaction, pile deflection) are included in separate editable files, enabling future reuse and development of the experimental results., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)