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Abstract: We propose a study of electrical properties of plastic solar modules with a combination of current density–voltage curves (J–V characteristics) and a non destructive Light/Laser Beam Induced Current (LBIC) technique. We first extract global electrical information and trends of modules provided by J–V curves after a warming up time and during a short illumination time. On the other hand, LBIC profiles and mappings are recorded and show the behavior of each individual cell of the module. The results allow us to identify the evolution and global trends of the module efficiency as a function of the evolution of each cell comprising the module according to a simple simulation model. At the same time, using LBIC mappings, we check the module uniformity and show that no microscopic defects coming from the deposition process of the films are visible. Finally, we reveal a module encapsulation failure. [Copyright &y& Elsevier]

Abstract: Angiotensin-converting enzyme (ACE) is a metallopeptidase that converts angiotensin I into angiotensin II. ACE is crucial in the control of cardiovascular and renal homeostasis and fertility in mammals. In vertebrates, both transmembrane and soluble ACE, containing one or two active sites, have been characterized. So far, only soluble, single domain ACEs from invertebrates have been cloned, and these have been implicated in reproduction in insects. Furthermore, an ACE-related carboxypeptidase was recently characterized in Leishmania, a unicellular eukaryote, suggesting the existence of ACE in more distant organisms. Interestingly, in silico databank analysis revealed that bacterial DNA sequences could encode putative ACE-like proteins, strikingly similar to vertebrates'' enzymes. To gain more insight into the bacterial enzymes, we cloned the putative ACE from the phytopathogenic bacterium, Xanthomonas axonopodis pv. citri, named XcACE. The 2 kb open reading frame encodes a 672-amino-acid soluble protein containing a single active site. In vitro expression and biochemical characterization revealed that XcACE is a functional 72 kDa dipeptidyl-carboxypeptidase. As in mammals, this metalloprotease hydrolyses angiotensin I into angiotensin II. XcACE is sensitive to ACE inhibitors and chloride ions concentration. Variations in the active site residues, highlighted by structural modelling, can account for the different substrate selectivity and inhibition profile compared to human ACE. XcACE characterization demonstrates that ACE is an ancestral enzyme, provoking questions about its appearance and structure/activity specialisation during the course of evolution. [Copyright &y& Elsevier]

This paper deals with organic solar cells (OSC) simulation using finite element method. Optical modeling is performed via finite difference time domain method whilst the continuity and Poisson's equations are solved to obtain electrical characteristics of the OSC. In this work, simulation results point out the OSC structure influence on its performances, either by the interface grating or by the ZnO optical spacer introduced between the active layer (P3HT:PCBM layer) and the metallic electrode. The comparison of modeling results and experimental measurement allows us to confirm and forecast the enhancement of the photovoltaic properties such as the power conversion efficiency. [ABSTRACT FROM AUTHOR]

A new series of cationic gold(i) pyrazole complexes were prepared in excellent yields as their perchlorate salts. Results of cell viability assays show that these novel complexes have good cytotoxic properties against the human HepG2 cancer cell line. These complexes showed promising anti-cancer activities and to our knowledge, pyrazoles have never been tested against this cell line. The regioselectivity of the complexation is also discussed in regards to the substitution pattern of the pyrazoles. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) is a prevalent epitranscriptomic mark in eukaryotic RNA, with crucial roles for mammalian and ecdysozoan development. Indeed, m6A‐RNA and the related protein machinery are important for splicing, translation, maternal‐to‐zygotic transition and cell differentiation. However, to date, the presence of an m6A‐RNA pathway remains unknown in more distant animals, questioning the evolution and significance of the epitranscriptomic regulation. Therefore, we investigated the m6A‐RNA pathway in the oyster Crassostrea gigas, a lophotrochozoan model whose development was demonstrated under strong epigenetic influence. Using mass spectrometry and dot blot assays, we demonstrated that m6A‐RNA is actually present in the oyster and displays variations throughout early oyster development, with the lowest levels at the end of cleavage. In parallel, by in silico analyses, we were able to characterize at the molecular level a complete and conserved putative m6A machinery. The expression levels of the identified putative m6A writers, erasers and readers were strongly regulated across oyster development. Finally, RNA pull‐down coupled to LC‐MS/MS allowed us to prove the actual presence of readers able to bind m6A‐RNA and exhibiting specific developmental patterns. Altogether, our results demonstrate the conservation of a complete m6A‐RNA pathway in the oyster and strongly suggest its implication in early developmental processes including MZT. This first demonstration and characterization of an epitranscriptomic regulation in a lophotrochozoan model, potentially involved in the embryogenesis, bring new insights into our understanding of developmental epigenetic processes and their evolution. [ABSTRACT FROM AUTHOR]

This paper deals with Organic Solar Cells (OSCs) simulation using finite element method. Optical modeling is performed via Finite Difference Time Domain method whereas the continuity and Poisson's equations are solved to obtain electrical characteristics of the OSC. In this work, simulation results point out the influence of physical parameters such as the exciton diffusion coefficient or the exciton lifetime on OSC performances. The comparison of modeling results and experimental measurement allows the exciton recombination, dissociation rate and lifetime to be determinated. [ABSTRACT FROM AUTHOR]

Highlights • Six different insulin related sequences are identified in Crassostrea gigas. • They belongs to three types based on disulfide bonds number and sequence homology. • The most related peptide to vertebrate insulin appears to be the ancestral form. • These peptides are expressed in nervous ganglia, digestive tissue and gonads. Abstract Insulin Related Peptides (IRPs) belong to the insulin superfamily and possess a typical structure with two chains, B and A, linked by disulphide bonds. As the sequence conservation is usually low between members, IRPs are classified according to the number and position of their disulphide bonds. In molluscan species, the first IRPs identified, named Molluscan Insulin-related Peptides (MIPs), exhibit four disulphide bonds. The genomic and transcriptomic data screening in the Pacific oyster Crassostrea gigas (Mollusc, Bivalvia) allowed us to identify six IRP sequences belonging to three structural groups. Cg-MIP1 to 4 have the typical structure of MIPs with four disulphide bonds. Cg-ILP has three disulphide bonds like vertebrate Insulin-Like Peptides (ILPs). The last one, Cg-MILP7 has a significant homology with Drosophila ILP7 (DILP7) associated with two additional cysteines allowing the formation of a fourth disulphide bond. The phylogenetic analysis points out that ILPs may be the most ancestral form. Moreover, it appears that ILP7 orthologs are probably anterior to lophotrochozoa and ecdysozoa segregation. In order to investigate the diversity of physiological functions of the oyster IRPs, we combine in silico expression data, qPCR measurements and in situ hybridization. The Cg-ilp transcript, mainly detected in the digestive gland and in the gonadal area, is potentially involved in the control of digestion and gametogenesis. The expression of Cg-mip4 is mainly associated with the larval development. The Cg-mip transcript shared by the Cg-MIP1, 2 and 3, is mainly expressed in visceral ganglia but its expression was also observed in the gonads of mature males. This pattern suggested the key roles of IRPs in the control of sexual reproduction in molluscan species. [ABSTRACT FROM AUTHOR]

Copper contamination is widespread along coastal areas and exerts adverse effects on marine organisms such as mollusks. In the Pacific oyster, copper induces severe developmental abnormalities during early life stages; however, the underlying molecular mechanisms are largely unknown. This study aims to better understand whether the embryotoxic effects of copper in Crassostrea gigas could be mediated by alterations in gene expression, and the putative role of DNA methylation, which is known to contribute to gene regulation in early embryo development. For that purpose, oyster embryos were exposed to 4 nominal copper concentrations (0.1, 1, 10 and 20 μg L −1 Cu 2+ ) during early development assays. Embryotoxicity was monitored through the oyster embryo-larval bioassay at the D-larva stage 24 h post fertilization (hpf) and genotoxicity at gastrulation 7 hpf. In parallel, the relative expression of 15 genes encoding putative homeotic, biomineralization and DNA methylation proteins was measured at three developmental stages (3 hpf morula stage, 7 hpf gastrula stage, 24 hpf D-larvae stage) using RT-qPCR. Global DNA content in methylcytosine and hydroxymethylcytosine were measured by HPLC and gene-specific DNA methylation levels were monitored using MeDIP-qPCR. A significant increase in larval abnormalities was observed from copper concentrations of 10 μg L −1 , while significant genotoxic effects were detected at 1 μg L −1 and above. All the selected genes presented a stage-dependent expression pattern, which was impaired for some homeobox and DNA methylation genes ( Notochord, HOXA1, HOX2, Lox5, DNMT3b and CXXC-1 ) after copper exposure. While global DNA methylation (5-methylcytosine) at gastrula stage didn’t show significant changes between experimental conditions, 5-hydroxymethylcytosine, its degradation product, decreased upon copper treatment. The DNA methylation of exons and the transcript levels were correlated in control samples for HOXA1 but such a correlation was diminished following copper exposure. The methylation level of some specific gene regions ( HoxA1, Hox2, Engrailed2 and Notochord ) displayed changes upon copper exposure. Such changes were gene and exon-specific and no obvious global trends could be identified. Our study suggests that the embryotoxic effects of copper in oysters could involve homeotic gene expression impairment possibly by changing DNA methylation levels. [ABSTRACT FROM AUTHOR]

A series of original 2-phenyl-3-(pyridin-4-yl)imidazo[1,2- a ]pyrazines and the 3-iodo precursors, bearing a polar moiety at the C-8 position, was synthesized and evaluated for their antileishmanial activities. Two derivatives exhibited very good activity against the promastigote and the amastigote forms of Leishmania major in the micromolar to submicromolar ranges, coupled with a low cytotoxicity against macrophages and 3T3 mouse fibroblast cells. Through Lm CK1 inhibition assay, investigations of the putative molecular target of these promising antileishmanial compounds will be discussed. [ABSTRACT FROM AUTHOR]

We present design principles for conceiving tangible user interfaces for the interactive physically-based deformation of 3D models. Based on these design principles, we developed a first prototype using a passive tangible user interface that embodies the 3D model. By associating an arbitrary reference material with the user interface, we convert the displacements of the user interface into forces required by physically-based deformation models. These forces are then applied to the 3D model made out of any material via a physical deformation model. In this way, we compensate for the absence of direct haptic feedback, which allows us to use a force-driven physically-based deformation model. A user study on simple deformations of various metal beams shows that our prototype is usable for deformation with the user interface embodying the virtual beam. Our first results validate our design principles, plus they have a high educational value for mechanical engineering lectures. [ABSTRACT FROM AUTHOR]

Histone methylation patterns are important epigenetic regulators of mammalian development, notably through stem cell identity maintenance by chromatin remodeling and transcriptional control of pluripotency genes. But, the implications of histone marks are poorly understood in distant groups outside vertebrates and ecdysozoan models. However, the development of the Pacific oyster Crassostrea gigas is under the strong epigenetic influence of DNA methylation, and Jumonji histone-demethylase orthologues are highly expressed during C. gigas early life. This suggests a physiological relevance of histone methylation regulation in oyster development, raising the question of functional conservation of this epigenetic pathway in lophotrochozoan. Quantification of histone methylation using fluorescent ELISAs during oyster early life indicated significant variations in monomethyl histone H3 lysine 4 (H3K4me), an overall decrease in H3K9 mono- and tri-methylations, and in H3K36 methylations, respectively, whereas no significant modification could be detected in H3K27 methylation. Early in vivo treatment with the JmjC-specific inhibitor Methylstat induced hypermethylation of all the examined histone H3 lysines and developmental alterations as revealed by scanning electronic microscopy. Using microarrays, we identified 376 genes that were differentially expressed under methylstat treatment, which expression patterns could discriminate between samples as indicated by principal component analysis. Furthermore, Gene Ontology revealed that these genes were related to processes potentially important for embryonic stages such as binding, cell differentiation and development. These results suggest an important physiological significance of histone methylation in the oyster embryonic and larval life, providing, to our knowledge, the first insights into epigenetic regulation by histone methylation in lophotrochozoan development. [ABSTRACT FROM AUTHOR]