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SummaryDental pulp is particularly interesting in regenerative medicine because of the accessibility and differentiation potential of the tissue. Dental pulp has an early developmental origin with multi-lineage differentiation potential as a result of its development during childhood and adolescence. However, no study has previously identified the presence of stem cell populations with embryonic-like phenotypes in human dental pulp from the third molar. In the present work, we describe a new population of dental pulp pluripotent-like stem cells (DPPSCs) that were isolated by culture in medium containing LIF, EGF and PDGF. , and they show genetic stability in vitro based on genomic analysis with a newly described CGH technique. Interestingly, DPPSCs were able to form both embryoid-body-like structures (EBs) in vitro and teratoma-like structures that contained tissues derived from all three embryonic germ layers when injected in nude mice. We examined the capacity of DPPSCs to differentiate in vitro into tissues that have similar characteristics to mesoderm, endoderm and ectoderm layers in both 2D and 3D cultures. We performed a comparative RT-PCR analysis of GATA4, GATA6, MIXL1, NANOG, OCT3/4, SOX1 and SOX2 to determine the degree of similarity between DPPSCs, EBs and human induced pluripotent stem cells (hIPSCs). Our analysis revealed that DPPSCs, hIPSC and EBs have the same gene expression profile. Because DPPSCs can be derived from healthy human molars from patients of different sexes and ages, they represent an easily accessible source of stem cells, which opens a range of new possibilities for regenerative medicine.

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We present an approach to improving the performance of solution processed organic semiconductor transistors based on a dual solvent system. We here apply this to a blend containing the p-conjugated small molecule 6,13 bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) and polystyrene, which acts as an inert binder. Using a semiconductor-binder solution of two solvents, where the main solvent is a better solvent of the small molecule and second solvent is a better solvent of the polymer, crystal morphologies can be altered and transistor mobilities increased by almost an order of magnitude. In this way, air-ambient and solution-processed transistors with linear and saturation mobilities higher than 1 cm 2 V À1 s À1 have been fabricated. We discuss how the solubility properties of the formulation components can be used to identify solvent candidates that promote an efficient self-assembly of the small molecule.

International audiencePhotovoltaic cells are characterized via a static relationship that describes their current-voltage relationship. This relationship is a complicated implicit algebraic equation that depends, in a nonlinear way, on two critical uncertain parameters: temperature and solar irradiance. The efficient operation of the panel relies on the knowledge of these key parameters. While it is technologically feasible to measure the former, a sensor for the latter is usually expensive and difficult to calibrate. In this paper, we propose a globally convergent estimator for solar irradiance which is developed using the principles of immersion and invariance recently reported in the control literature. To design the estimator, a suitable reparameterization of the current-voltage characteristic, which effectively exhibits a monotonic behavior, is introduced. The approach is validated through detailed computer simulations and experimental prototyping using real outdoor measurements

In this paper, we first remember the mathematical formulation of an original variance-expected compliance model used for structural optimization. It allows us to find robust structures for the main load and its perturbations. In the second part, we valid this model on a 3-D benchmark test case and compare the results obtained to those given by a classical expected compliance model.

We have studied the effects in vitro of gastrin-17 and gastrin-34, at concentrations from 10(-14) M to 10(-6) M, on several of the functions of peripheral blood human neutrophils, i.e. adherence to substrate, mobility (spontaneous and directed by a chemical gradient or chemotaxis), ingestion of inert particles (latex beads) and cells (Candida albicans) and superoxide anion production. Both gastrins inhibited several steps of the phagocytic process of human neutrophils, such as mobility and ingestion. By contrast, these peptides increased adherence and had no effect on superoxide anion production. In general, these effects were significant at peptide concentrations between 10(-12) M and 10(-8) M with a maximal effect at 10(-10) M. In addition, gastrin peptides induced a significant increase in intracellular cAMP levels at 30, 60 and 120 s. Moreover, the inhibitory effect of gastrin-17 on the ingestion capacity of neutrophils (latex bead phagocytosis) was similar to that obtained with EGTA, a well-known extracellular calcium chelating compound. Gastrin-17 was found to inhibit completely the stimulation of latex bead phagocytosis in neutrophils caused by the calcium ionophore A23187. These results suggest that gastrin is a negative modulator of the phagocytic process of human neutrophils, and that this effect might involve an increase in intracellular cAMP levels and a decrease in calcium entry into the cells.