Effect of high temperatures on sex ratio and differential expression analysis (RNA-seq) of sex-determining genes in <i>Oreochromis niloticus</i> from different river basins in Benin

peer reviewedAbstract The high temperature sex reversal process leading to functional phenotypic masculinization during development has been widely described in Nile tilapia (Oreochromis niloticus) under laboratory or aquaculture conditions and in the wild. In this study, we selected five wild populations of O. niloticus from different river basins in Benin and produced twenty full-sib families of mixed-sex (XY and XX) by natural reproduction. Progenies were exposed to room temperature or high (36.5°C) temperatures between 10 and 30 days post-fertilization (dpf). In control groups, we observed sex ratios from 40 to 60% males as expected, except for 3 families from the Gobé region which showed a bias towards males. High temperature treatment significantly increased male rates in each family up to 88%. Transcriptome analysis was performed by RNA-sequencing (RNA-seq) on brains and gonads from control and treated batches of six families at 15 dpf and 40 dpf. Analysis of differentially expressed genes, differentially spliced genes, and correlations with sex reversal was performed. In 40 dpf gonads, genes involved in sex determination such as dmrt1, cyp11c1, amh, cyp19a1b, ara, and dax1 were upregulated. In 15 dpf brains, a negative correlation was found between the expression of cyp19a1b and the reversal rate, while at 40 dpf a negative correlation was found between the expression of foxl2, cyp11c1, and sf1 and positive correlation was found between dmrt1 expression and reversal rate. Ontology analysis of the genes affected by high temperatures revealed that male sex differentiation processes, primary male sexual characteristics, autophagy, and cilium organization were affected. Based on these results, we conclude that sex reversal by high temperature treatment leads to similar modifications of the transcriptomes in the gonads and brains in offspring of different natural populations of Nile tilapia, which thus may activate a common cascade of reactions inducing sex reversal in progenies

Layer Morphology and Ink Compatibility of Silver Nanoparticle Inkjet Inks for Near-Infrared Sintering

The field of printed electronics is rapidly evolving, producing low cost applications with enhanced performances with transparent, stretchable properties and higher reliability. Due to the versatility of printed electronics, industry can consider the implementation of electronics in a way which was never possible before. However, a post-processing step to achieve conductive structures&mdash;known as sintering&mdash;limits the production ease and speed of printed electronics. This study addresses the issues related to fast sintering without scarifying important properties such as conductivity and surface roughness. A drop-on-demand inkjet printer is employed to deposit silver nanoparticle-based inks. The post-processing time of these inks is reduced by replacing the conventional oven sintering procedure with the state-of-the-art method, named near-infrared sintering. By doing so, the post-processing time shortens from 30&ndash;60 min to 6&ndash;8 s. Furthermore, the maximum substrate temperature during sintering is reduced from 200 &deg;C to 120 &deg;C. Based on the results of this study, one can conclude that near-infrared sintering is a ready-to-industrialize post-processing method for the production of printed electronics, capable of sintering inks at high speed, low temperature and with low complexity. Furthermore, it becomes clear that ink optimization plays an important role in processing inkjet printable inks, especially after being near-infrared sintered

Thermo-Mechanical Stress Comparison of a GaN and SiC MOSFET for Photovoltaic Applications

Integrating photovoltaic applications within urban environments creates the need for more compact and efficient power electronics that can guarantee long lifetimes. The upcoming wide-bandgap semiconductor devices show great promise in providing the first two properties, but their packaging requires further testing in order to optimize their reliability. This paper demonstrates one iteration of the design for reliability methodology used in order to compare the generated thermo-mechanical stress in the die attach and the bond wires of a GaN and SiC MOSFET. An electro-thermal model of a photovoltaic string inverter is used in order to translate a cloudy and a clear one-hour mission profile from Arizona into a junction losses profile. Subsequently, the finite element method models of both devices are constructed through reverse engineering in order to analyze the plastic energy. The results show that the plastic energy in the die attach caused by a cloudy mission-profile is much higher than that caused by a clear mission-profile. The GaN MOSFET, in spite of its reduced losses, endures around 5 times more plastic energy dissipation density in its die attach than the SiC MOSFET while the reverse is true for the bond wires. Potential design adaptations for both devices have been suggested to initiate a new iteration in the design for reliability methodology, which will ultimately lead to a more reliable design

The Sensitivity of an Electro-Thermal Photovoltaic DC-DC Converter Model to the Temperature Dependence of the Electrical Variables for Reliability Analyses

status: publishe

The Sensitivity of an Electro-Thermal Photovoltaic DC–DC Converter Model to the Temperature Dependence of the Electrical Variables for Reliability Analyses

The operational expenditures of solar energy are gaining attention because of the continuous decrease of the capital expenditures. This creates a demand for more reliable systems to further decrease the costs. Increased reliability is often ensured by iterative use of design for reliability. The number of iterations that can take place strongly depends on the computational efficiency of this methodology. The main research objective is to quantify the influence of the temperature dependence of the electrical variables used in the electro-thermal model on the reliability and the computation time. The influence on the reliability is evaluated by using a 2-D finite elements method model of the MOSFET and calculating the plastic energy dissipation density in the die-attach and the bond wire. The trade-off between computation time of the electro-thermal model in PLECS (4.3, Plexim, Zurich, Switzerland) and generated plastic energy accuracy obtained in COMSOL (5.3, COMSOL Inc., Burlington, MA, USA) is reported when excluding a certain temperature dependence. The results indicate that the temperature dependence of the input and output capacitors causes no change in the plastic energy dissipated in the MOSFET but does introduce the largest increase in computation time. However, not including the temperature dependence of the MOSFET itself generates the largest difference in plastic energy of 10% as the losses in the die are underestimated

J-DISTAS: a new tool to predict field readiness to ensure efficiency of field operations and avoid soil compaction

International audienceSustainable crop production implies high efficiency of field operations and protection of the soil as a natural resource. Soil physical fertility is threatened by compaction, especially deep soil horizons for which remediation is more critical (Schjonning et al., 2015). To avoid soil compaction and ensure field operations efficiency, including satisfactory crop production in a cost-effective way, the prediction of field readiness, defined as the combination of soil workability and soil trafficability, is of prime interest (Edwards et al., 2016). The currently available tools are generally focused on only one part of the problem (either soil compaction risk in deep soil horizon or possibility of efficient field operation), and are usually built for a specific pedoclimatic context, which raises question of their application in a broader context. They also need to be upgraded to consider agricultural equipment evolution.The J-DISTAS project (2019-2022) aims at creating a prototype of interoperable tool to predict field readiness. This tool will combine: (i) the evaluation of the soil compaction risk using the Terranimo® model (terranimo.dk) and the CHN crop model, and (ii) expert models estimating soil water potential and soil workability (Ugarte Nano et al., 2021). This decision support tool will allow strategic decisions based on field readiness consideration such as definition of cropping systems in the context of global changes, optimization of the use of agricultural machinery, etc.We will present i) the J-Distas tool’s ability to predict field readiness, ii) its sensitivity to input data, and iii) an example of its use

J-DISTAS: a new tool to predict field readiness to ensure efficiency of field operations and avoid soil compaction

International audienceSustainable crop production implies high efficiency of field operations and protection of the soil as a natural resource. Soil physical fertility is threatened by compaction, especially deep soil horizons for which remediation is more critical (Schjonning et al., 2015). To avoid soil compaction and ensure field operations efficiency, including satisfactory crop production in a cost-effective way, the prediction of field readiness, defined as the combination of soil workability and soil trafficability, is of prime interest (Edwards et al., 2016). The currently available tools are generally focused on only one part of the problem (either soil compaction risk in deep soil horizon or possibility of efficient field operation), and are usually built for a specific pedoclimatic context, which raises question of their application in a broader context. They also need to be upgraded to consider agricultural equipment evolution.The J-DISTAS project (2019-2022) aims at creating a prototype of interoperable tool to predict field readiness. This tool will combine: (i) the evaluation of the soil compaction risk using the Terranimo® model (terranimo.dk) and the CHN crop model, and (ii) expert models estimating soil water potential and soil workability (Ugarte Nano et al., 2021). This decision support tool will allow strategic decisions based on field readiness consideration such as definition of cropping systems in the context of global changes, optimization of the use of agricultural machinery, etc.We will present i) the J-Distas tool’s ability to predict field readiness, ii) its sensitivity to input data, and iii) an example of its use

Anti-Cancer Activity of Resveratrol and Derivatives Produced by Grapevine Cell Suspensions in a 14 L Stirred Bioreactor

In the present study, resveratrol and various oligomeric derivatives were obtained from a 14 L bioreactor culture of elicited grapevine cell suspensions (Vitis labrusca L.). The crude ethyl acetate stilbene extract obtained from the culture medium was fractionated by centrifugal partition chromatography (CPC) using a gradient elution method and the major stilbenes contained in the fractions were subsequently identified by using a 13C-NMR-based dereplication procedure and further 2D NMR analyses including HSQC, HMBC, and COSY. Beside δ-viniferin (2), leachianol F (4) and G (4′), four stilbenes (resveratrol (1), ε-viniferin (5), pallidol (3) and a newly characterized dimer (6)) were recovered as pure compounds in sufficient amounts to allow assessment of their biological activity on the cell growth of three different cell lines, including two human skin malignant melanoma cancer cell lines (HT-144 and SKMEL-28) and a healthy human dermal fibroblast HDF line. Among the dimers obtained in this study, the newly characterized resveratrol dimer (6) has never been described in nature and its biological potential was evaluated here for the first time. ε-viniferin as well as dimer (6) showed IC50 values on the three tested cell lines lower than the ones exerted by resveratrol and pallidol. However, activities of the first two compounds were significantly decreased in the presence of fetal bovine serum although that of resveratrol and pallidol was not. The differential tumor activity exerted by resveratrol on healthy and cancer lines was also discussed

Cytotoxicity of Labruscol, a New Resveratrol Dimer Produced by Grapevine Cell Suspensions, on Human Skin Melanoma Cancer Cell Line HT-144

A new resveratrol dimer (1) called labruscol, has been purified by centrifugal partition chromatography of a crude ethyl acetate stilbene extract obtained from elicited grapevine cell suspensions of Vitis labrusca L. cultured in a 14-liter stirred bioreactor. One dimensional (1D) and two dimensional (2D) nuclear magnetic resonance (NMR) analyses including 1H, 13C, heteronuclear single-quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and correlation spectroscopy (COSY) as well as high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) were used to characterize this compound and to unambiguously identify it as a new stilbene dimer, though its relative stereochemistry remained unsolved. Labruscol was recovered as a pure compound (&gt;93%) in sufficient amounts (41 mg) to allow assessment of its biological activity (cell viability, cell invasion and apoptotic activity) on two different cell lines, including one human skin melanoma cancer cell line HT-144 and a healthy human dermal fibroblast (HDF) line. This compound induced almost 100% of cell viability inhibition in the cancer line at a dose of 100 μM within 72 h of treatment. However, at all tested concentrations and treatment times, resveratrol displayed an inhibition of the cancer line viability higher than that of labruscol in the presence of fetal bovine serum. Both compounds also showed differential activities on healthy and cancer cell lines. Finally, labruscol at a concentration of 1.2 μM was shown to reduce cell invasion by 40%, although no similar activity was observed with resveratrol. The cytotoxic activity of this newly-identified dimer is discussed

INTERCONNECTION 1, 2, 3, 4.0: BUILDUP TOWARDS A PV TECHNOLOGY HERO?

status: Published onlin