Stress Engineering in Germanium-Silicon Heterostructure Using Surface Activated Hot Bonding

International audienceThe manufacturing of heterostructures is interesting in many fields such as photonics, solar energy production and quantum technologies. This paper, dedicated to germanium on silicon heterostructure manufacturing and stress engineering, builds up on LETI and EVGroup’s hot bonding technology (1). The coefficients of thermal expansion (CTE) mismatch between germanium and silicon is used to induce some in-plane tensile stress in a thin germanium layer transferred by the Smart Cut TM technique onto a silicon substrate. In this approach, a bulk germanium wafer is directly bonded on a bulk silicon wafer, using surface activated hot bonding (SAHB). Process integration advantages are the low defect density of bulk germanium and the tensile stress that can be tuned using the bonding temperature. According to X-Ray diffraction measurements, for a bonding performed at 250°C, the lattice parameter deformation reached +0.06%, resulting in a 82 MPa tensile stress in a 370 nm thick germanium layer

Downregulation of sphingosine kinase-1 induces protective tumor immunity by promoting M1 macrophage response in melanoma

The infiltration of melanoma tumors by macrophages is often correlated with poor prognosis. However, the molecular signals that regulate the dialogue between malignant cells and the inflammatory microenvironment remain poorly understood. We previously reported an increased expression of sphingosine kinase-1 (SK1), which produces the bioactive lipid sphingosine 1-phosphate (S1P), in melanoma. The present study aimed at defining the role of tumor SK1 in the recruitment and differentiation of macrophages in melanoma. Herein, we show that downregulation of SK1 in melanoma cells causes a reduction in the percentage of CD206highMHCIIlow M2 macrophages in favor of an increased proportion of CD206lowMHCIIhigh M1 macrophages into the tumor. This macrophage differentiation orchestrates T lymphocyte recruitment as well as tumor rejection through the expression of Th1 cytokines and chemokines. In vitro experiments indicated that macrophage migration is triggered by the binding of tumor S1P to S1PR1 receptors present on macrophages whereas macrophage differentiation is stimulated by SK1-induced secretion of TGF-β1. Finally, RNA-seq analysis of human melanoma tumors revealed a positive correlation between SK1 and TGF-β1 expression. Altogether, our findings demonstrate that melanoma SK1 plays a key role in the recruitment and phenotypic shift of the tumor macrophages that promote melanoma growth.Mrad, Marguerite Imbert, Caroline Garcia, Virginie Rambow, Florian Therville, Nicole Carpentier, Stephane Segui, Bruno Levade, Thierry Azar, Rania Marine, Jean-Christophe Diab-Assaf, Mona Colacios, Celine Andrieu-Abadie, Nathalie eng 2016/10/07 06:00 Oncotarget. 2016 Nov 1;7(44):71873-71886. doi: 10.18632/oncotarget.12380. The infiltration of melanoma tumors by macrophages is often correlated with poor prognosis. However, the molecular signals that regulate the dialogue between malignant cells and the inflammatory microenvironment remain poorly understood. We previously reported an increased expression of sphingosine kinase-1 (SK1), which produces the bioactive lipid sphingosine 1-phosphate (S1P), in melanoma. The present study aimed at defining the role of tumor SK1 in the recruitment and differentiation of macrophages in melanoma. Herein, we show that downregulation of SK1 in melanoma cells causes a reduction in the percentage of CD206highMHCIIlow M2 macrophages in favor of an increased proportion of CD206lowMHCIIhigh M1 macrophages into the tumor. This macrophage differentiation orchestrates T lymphocyte recruitment as well as tumor rejection through the expression of Th1 cytokines and chemokines. In vitro experiments indicated that macrophage migration is triggered by the binding of tumor S1P to S1PR1 receptors present on macrophages whereas macrophage differentiation is stimulated by SK1-induced secretion of TGF-beta1. Finally, RNA-seq analysis of human melanoma tumors revealed a positive correlation between SK1 and TGF-beta1 expression. Altogether, our findings demonstrate that melanoma SK1 plays a key role in the recruitment and phenotypic shift of the tumor macrophages that promote melanoma growth.status: publishe

Rapport du projet. Développement d'outils méthodologiques pour l'évaluation de biocénoses marines et de ressources halieutiques d'intérêt régional en vue de leur conservation ou de leur valorisation durable. DESCARTES 2

Descartes 2 propose la mise au point et l'optimisation de protocoles d'échantillonnage qualifiant les biocénoses marines et des ressources halieutiques d'intérêt régional sur deux types de milieux aquitains : la côte basque rocheuse et le bassin d'Arcachon. Tester et définir des méthodes d'échantillonnage fiables, applicables en routine et transférables, requièrent une phase de recherche impliquant des compétences en mathématiques, hydrodynamique, sciences du vivant. Le projet contribuera ainsi, par des actions scientifiques, à l'amélioration des politiques publiques pour la gestion du milieu marin, y compris sur des problématiques transfrontalières. Par ailleurs le projet Descartes 2 vise à contribuer au renforcement durable du partenariat pluridisciplinaire existant avec le monde académique (UPPA) via la Fédération de Recherche MIlieux et Ressources Aquatiques (FR MIRA). Il concerne l'axe de recherche prioritaire « Fonctionnement des populations naturelles et perturbations »pour lequel l'Université affiche des orientations de recherche

Naturally occurring melanomas in dogs as models for non-UV pathways of human melanomas.

International audienceSpontaneously occurring melanomas are frequent in dogs. They appear at the same localizations as in humans, i.e. skin, mucosal sites, nail matrix and eyes. They display variable behaviors: tumors at oral localizations are more frequent and aggressive than at other anatomical sites. Interestingly, dog melanomas are associated with strong breed predispositions and overrepresentation of black-coated dogs. Epidemiological analysis of 2350 affected dogs showed that poodles are at high risk of developing oral melanoma, while schnauzers or Beauce shepherds mostly developped cutaneous melanoma. Clinical and histopathological analyses were performed on a cohort of 153 cases with a 4-yr follow-up. Histopathological characterization showed that most canine tumors are intradermal and homologous to human rare morphological melanomas types - 'nevocytoid type' and 'animal type'-. Tumor cDNA sequencing data, obtained from 95 dogs for six genes, relevant to human melanoma classification, detected somatic mutations in oral melanoma, in NRAS and PTEN genes, at human hotspot sites, but not in BRAF. Altogether, these findings support the relevance of the dog model for comparative oncology of melanomas, especially for the elucidation of non-UV induced pathways

Validation and inter-comparison of models for landslide tsunami generation

10.1016/j.ocemod.2021.101943OCEAN MODELLING17