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This study aimed to discuss the combined theoretical and experimental results of elastic properties of the tungsten trioxide films supported on Quartz (YX)/45°/10° resonator, as surface acoustic wave (SAW) device. The SAW system with different thicknesses of WO3 thin films were imaged and structurally characterized by X-Ray diffraction, atomic force and transmission electron microscopy. The deposited WO3 films (100 nm, 200 nm and 300 nm) were crystallized in a single monoclinic phase. The acoustoelectric properties of the SAW system were obtained by combining theoretical simulations with experimental measurements. The modeling of the SAW devices has been performed by the finite element and boundary element methods (FEM/BEM). The theoretical and experimental electrical admittances responses obtained at room temperature gave access to elastic constants. The gravimetric effect of the deposited layers is observed by a resonance frequencies shift to lower values with thicknesses film. Moreover, the acoustic losses are affected by the dielectric losses of the WO3 films, while the resonant frequency decreases almost linearly. SAW devices revealed strong displacement fields with low acoustic losses as a function of WO3 thicknesses. For all the deposited layers, the Young's modulus and the Poisson coefficient obtained are respectively of 8 GPa and 0.5.

The orthorhombic LaFeO3 thin films grown by pulsed laser deposition on silicon showed nano-structuration of their surface and preferential crystallographic exposed facets, depending on the deposition temperature. The LaFeO3 film deposited at 850 °C has two types of grain termination, flat or tip-like, corresponding to two different growth directions, respectively [110] and [200]. However, due to the shape of the termination, the two types of grains expose the same {110} facets. The prepared lanthanum iron oxide films are iron deficient and consequently contains oxygen vacancies, the exact chemical formula being LaFe0.82O3-δ.

International audience; The aim of this study was to observe the effect of feed restriction (FR) on milk concentrations of major proteins and microRNA in order to identify potential biomarkers of negative energy balance in cows. We hypothesized that the effects of FR on mammary gland metabolism are reflected in milk and its different fractions. Two FR trials were conducted at mid lactation to induce negative energy balance: a short duration and high intensity one (SH) and a long duration and moderate intensity one (LM). The SH experiment involved 8 Holstein cows. The LM experiment involved 19 Holstein cows either in control (n=9) or restriction conditions (n=10). FR lasted 6 and 29 days with a dry matter intake reduced by 64 and 20% of ad libitum intake, and induced a negative energy balance of-42 and-21 MJ/d, respectively for SH and LM experiments. Milk was sampled before, during (3 times for LM) and after the restriction periods. MicroRNA, extracted from whole milk, fat globules, milk isolated mammary epithelial cells and extracellular vesicles were sequenced and protein concentrations analyzed using LC-MS. Concentration of several major proteins decreased during FR: αS2-casein (LM and SH), αS1-casein (SH), κ-casein (LM), α-lactalbumin (LM), β-lactoglobulin (LM). Among 2896 microRNA detected in milk, the abundance of 159 microRNA was affected by FR, mostly in extracellular vesicles (n=83) and whole milk (n=85), few in fat globules (n=6), but none in mammary epithelial cells. Among these 159 microRNA, 15 varied in two compartments. These experiments showed that FR affects the abundance of proteins and microRNA in milk. It may reflect modifications of mammary gland metabolism. These results will be further explored by proteomic analysis and by RT-qPCR on more samples. These preliminary results are promising in the search for non-invasive biomarkers of negative energy balance in milk.

International audience; Evolutionary selective pressure on lactation has resulted in milk that provides far more than simply essential nutrients, delivering a complex repertoire of agents from hormones to intact cells. Human infants are born with low barrier integrity of their gut, which means that many of the complex biopolymer components of milk enter and circulate in lymph and blood, reaching organs throughout the body. Due to this state of gut maturation, all components of milk are potentially part of the crosstalk between mother and infants. This article highlights the functions of milk's complex biopolymers, more specifically the potential role of microRNAs (miRNAs) contained in extracellular vesicles in human milk. miRNAs are key effectors in the regulation of many biological processes during early-age development, and consequently milk-sourced miRNAs must be considered to provide unique biological assets to the infant during breastfeeding. This article interprets the evidence of the potential action of human milk miRNAs on infant development, taking into account their abundance in milk based on the literature and current knowledge. Human milk miRNAs appear to influence lipid and glucose metabolism, gut maturation, neurogenesis, and immunity. We also show growing evidence that human milk miRNAs are epigenetic modulators that play a pivotal role in the regulation of tissue-specific gene expression throughout life. Furthermore, this article addresses the ongoing debate regarding the potential influence of human milk miRNAs on viral infection as a new research area. This article highlights that these bioactive molecules are now being incorporated into our overall understanding of nutrient needs for healthy infant development, preparing each individual infant to succeed as a healthy and protected adult throughout its life. In essence, miRNAs are a new language in the Rosetta stone of health that is mammalian lactation.

International audience; In mammals, milk is essential for the growth, development, and health. Milk quantity and quality are dependent on mammary development, strongly influenced by nutrition. This review provides an overview of the data on nutritional regulations of mammary development and gene expression involved in milk component synthesis. Mammary development is described related to rodents, rabbits, and pigs, common models in mammary biology. Molecular mechanisms of the nutritional regulation of milk synthesis are reported in ruminants regarding the importance of ruminant milk in human health. The effects of dietary quantitative and qualitative alterations are described considering the dietary composition and in regard to the periods of nutritional susceptibly. During lactation, the effects of lipid supplementation and feed restriction or deprivation are discussed regarding gene expression involved in milk biosynthesis, in ruminants. Moreover, nutrigenomic studies underline the role of the mammary structure and the potential influence of microRNAs. Knowledge from three lactating and three dairy livestock species contribute to understanding the variety of phenotypes reported in this review and highlight (1) the importance of critical physiological stages, such as puberty gestation and early lactation and (2) the relative importance of the various nutrients besides the total energetic value and their interaction.

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International audience; Aluminum powders are commonly used in energetics materials and it is possible to improve their reactivity by preparing them as nanopowders. In this article, it is shown that high-energy ball milling can be used to tune the reactivity of nanoflakes. Several nanopowders are synthesized using three different grinding ball diameters (5 mm, 10 mm and 15 mm). The powders are characterized in terms of morphology, structure and microstructure. Changing the diameter of the grinding balls results in powders with different characteristics. Among the three diameters used, an optimum is found for powders synthetized with 10 mm diameter balls: they possess the highest specific area, the smallest aluminum crystallites and the lowest amount of deformation. The reactivity of the various nanopowders, evaluated using thermal analysis under air, is shown to be dependent on both textural and microstructural properties of the powders. Such considerations on the microstructural properties of nanopowders are of utmost importance in the quest for the best materials for energetics applications.

International audience; In addition to the major and well-known milk components, nutritional quality of milk is also influenced by recently detected components, such as miRNAs that regulate many biological processes. They were found in different fractions of milk including extracellular vesicles (EVs). Evidence of the presence of food-sourced miRNAs in human plasma suggests that they could influence human health. In goats, the polymorphisms occurring at the CSN1S1 locus deeply impact mammary epithelial cell (MEC) function and milk composition. We hypothesized that this polymorphism may influence cargo miRNA in milk-derived EVs. Our objectives were to: i) characterize the miRNome from milk-derived EVs; ii) compare the miRNomes of strong (AA) vs natural-KO (OO) genotypes and hypothesize on the putative effects on milk consumers. Total RNA isolated from EVs was subjected to RNAseq using Illumina NextSeq500. Sequences were mapped on Bos taurus genome (UMD3.1) and miRBase. Differential analyses, multiple testing correction and bioinformatics analyses were performed.

International audience; The catalytic efficiency as well as the electrical conduction mechanism of Ce2(WO4)3 powders synthetized for the oxidation of methane were investigated. Total and partial oxidation reactions were observed in the temperature range between 600 and 750 °C under CH4/dry air flux, for low CH4 concentrations. The electrical conduction mechanism is based on electron tunneling at low temperature (< 650 °C) and hopping over an ion barrier at high temperature, which favors the catalytic oxidation of CH4 in air; these mechanisms occur during the partial and total oxidation under weak gas flow. The occurrence of these types of conduction mechanism was related both to the distorted monoclinic structure of Ce2(WO4)3 and to the larger structural cavities, as evidenced respectively by X-ray diffraction analyses (Rietveld analyses) and high-resolution transmission electron microscopy. The oxidation state of cerium is 3 + in the compound, as revealed by XPS investigations.

The objective was to investigate the effects of feed restriction on concentrations of selected milk metabolites in mid-lactation Holstein and Montbéliarde cows and to explore their correlations with energy balance and classic plasma and milk indicators of nutritional status. Eight Holstein and 10 Montbéliarde cows (165 ± 21 d in milk) underwent 6 d of feed restriction during which feed allowance was reduced to meet 50% of their net energy for lactation (NEL) requirements. The experiment was divided in 4 periods: control (CON; d −3 to −1), restriction (RES; d 1 to 6), wk 1 (W1; d 7 to 13), and wk 2 (W2; d 14 to 18) after refeeding at ad libitum intake. Intake, milk production, energy balance and plasma metabolites were used to validate the feed restriction model. Concentrations of 7 milk metabolites: β-hydroxybutyrate (BHB), glucose, glucose-6-phosphate, isocitrate, glutamate, uric acid, and free amino groups were measured in morning milk samples, and fatty acids were measured in pooled p.m. and a.m. samples. Feed restriction induced a negative energy balance (−42.5 ± 4.4 MJ/d), increased plasma nonesterified fatty acids and BHB, and decreased plasma glucose concentrations. Feed restriction increased milk glucose-6-phosphate and isocitrate (+38% and +39%, respectively) and decreased milk BHB, glucose, glutamate, uric acid and free amino group concentrations (−20%, −57%, −65%, −42%, and −14%, respectively), compared with pre- restriction. Milk concentrations of medium-chain fatty acids (e.g., sum of C10 to C15) decreased and those of long chain (e.g., 18:0, cis-9 18:1) increased during restriction. Breed differences were not detected for the majority of variables. All studied milk metabolites were significantly correlated with energy balance (Spearman correlation = 0.48, 0.63, −0.31, −0.45, and 0.61 for BHB, glucose, glucose-6-phosphate, isocitrate, and glutamate, respectively). Milk glucose and glutamate showed the strongest correlations with plasma metabolites and milk FA associated with lipomobilization. These results suggest that milk metabolites may be used as noninvasive indicators of negative energy balance and metabolic status of dairy cows.

International audience; Despite the unavoidable presence of silicon atoms in the catalyst alloy droplets during the vapor-liquid-solid growth of III-V nanowires on silicon substrates, it remains unknown how the nucleation of nanowires is affected by these foreign atoms. In this work, we present the first attempt to quantify the nanowire nucleation rate versus the silicon concentration in the droplet. We calculate the chemical potential difference per Ga-As pair in the quaternary Au-Ga-As-Si liquid alloy droplet and in solid state, and compare it to the ternary Au-Ga-As droplet without silicon. This allows us to compute the nucleation rates of GaAs nanowires versus the silicon concentration under different conditions. We find that the presence of silicon in the droplet decreases the nucleation probability of GaAs nanowires for gallium-rich droplets (with the gallium contents c(GA) greater than 0.6) and increases it for gold-rich droplets (c(GA) < 0.6). The model is used to explain our experimental data for hydride vapor phase epitaxy of gold-catalyzed GaAs nanowires, which easily nucleate on Si(111) covered with different SiO2 layers but do not grow on the bare Si(111). In the latter case, more silicon is etched from the substrate and enters the gallium-rich droplets, which suppresses the nanowire nucleation. We discuss other relevant data, including the known difficulties in obtaining self-assisted GaAs NWs on silicon by chemical epitaxy techniques. These results may be useful for the fine-tuning of III-V nanowire properties and integrating them with silicon electronics.

Adipose tissue is the energy storage organ providing energy to other tissues, including mammary gland, that supports the achievement of successive lactation cycles. Our objective was to investigate the ability of goats to restore body fat reserves by comparing lipogenic enzyme activities and by transcriptomic RNA-Seq data at two different physiological stages, mid- and post-lactation. Key lipogenic enzyme activities were higher in goat omental adipose tissue during mid-lactation (74 days in milk) than during the post-lactation period (300 days postpartum). RNA-Sequencing analysis revealed 19,271 expressed genes in the omental adipose tissue. The comparison between adipose transcriptome analysis from mid- and post-lactation goats highlighted 252 differentially expressed genes (p

Introduction: Alors que les patients partenaires sont de plus en plus impliqués en ETP, leurs expériences à la suite de leurs pratiques ont peu été explorées. Objectif : Comprendre comment les patients partenaires évaluent leurs activités et rôles en ETP, en Auvergne (France). Méthodes : Une étude quantitative d’une durée d’un mois a été proposée à vingt patients partenaires d’Auvergne. Les données qualitatives ont été exploitées par catégorisation thématique, en respectant une triangulation de méthodes et d’analyse. Résultats : Onze patients partenaires ont participé à l’ensemble de l’étude. Un total de 107 catégories de vécues ont été décrites dont la majorité était à connotation positive (76,6 %). Les patients partenaires ont mentionné 90 verbatim décrivant des aptitudes et compétences nécessaires à leurs activités, principalement relationnelles et pédagogiques (37 %) puis intrapersonnelles (31 %). Ces données recueillies s’accompagnaient de besoins d’échanges sur leurs rôles et leurs postures ainsi que d’acquisition de nouvelles compétences. Discussion : Les patients partenaires réalisent des activités et formations multiples en lien avec l’ETP et ont un statut particulier. Ceci leur permet d’acquérir et mobiliser de nombreuses compétences, mais engendre aussi une difficulté de reconnaissance et d’identification auprès des institutions. Des besoins d’échanges entre pairs, structurés, stables et en groupe, apparaissent. Conclusion : Les patients partenaires possèdent une curiosité intellectuelle salutogénique les poussant à se former et à développer leurs activités. Cependant, ces élans et investissements doivent être soutenus au niveau régional, voire national, afin d’en assurer la pérennité.

Examples of current research on indicators of adaptative response in periparturient dairy ruminants. Adipose tissue in livestock. Cycle de conférences 'Global Health'

International audience; MicroRNAs (miRNAs) are small noncoding RNAs present in milk-derived extracellular vesicles and milk fat globules(MFG). Nucleic acid content between the lactating mammary tissue (MT) and MFG are quite similar but discrepanciesexist in their miRNA content. Our objective was to identify the origin of these discrepancies, and to evaluate the existenceof a possible mechanism sorting miRNAs that will or will not be exported from the mammary epithelial cells (MECs) inbovine MFG. miR-125b-5p, miR-126-3p, miR-141-3p, and miR-204-5p, chosen on the basis of their abundance in the MT,were quantified using RT-qPCR in lactating cow MT, MFG, and laser capture-microdissected MECs. Two miRNAs (miR-125b-5p and miR-141-3p) were detected in the MT as well as in MFG and MECs. miR-204-5p was detected only in the MT,suggesting that it is very likely expressed in a cell type other than MECs. miR-126-3p was detected both in the MT and inMECs but not in MFG, suggesting a targeting mechanism for miRNAs in MECs. These results highlights differences inmiRNA content between MECs and MFG may be due to a possibly not random mechanism for loading MFG with miRNAcargos that could involve a variable distribution in MECs or a sorting mechanism.

The incorporation of Si into vapor-liquid-solid GaAs nanowires often leads to p-type doping, whereas it is routinely used as an n-dopant of planar layers. This property limits the applications of GaAs nanowires in electronic and optoelectronic devices. The strong amphoteric behavior of Si in nanowires is not yet fully understood. Here, we present the first attempt to quantify this behavior as a function of the droplet composition and temperature. It is shown that the doping type critically depends on the As/Ga ratio in the droplet. In sharp contrast to vapor-solid growth, the droplet contains very few As atoms, which enhance their reverse transfer from solid to liquid. As a result, Si atoms preferentially replace As in GaAs, leading to p-type doping in nanowires. Hydride vapor phase epitaxy provides the highest As concentrations in the catalyst droplets during their vapor-liquid-solid growth, resulting in n-type dopant behavior of Si. We present experimental data on n-doped Si-doped GaAs nanowires grown by this method and explain the doping within our model. These results give a clear route for obtaining n-type or p-type Si doping in GaAs nanowires and may be extended to other III-V nanowires.

International audience; LaLuO3 amorphous thin films were elaborated by pulsed laser deposition technique on different support: Si (100), Si(100) with buffer layer CeO2, MgO(111) and Al2O3 (1101). For obtained the crystallizes phase the thin films were annealed in temperature 1100 degrees C in air during 2 h. TEM analysis clearly showed the reaction between Si support and LaLuO3 thin films and their polycrystalline structure. The spectroscopy investigations indicate the reaction between Si support and LaLuO3 thin films and formation of silicates. The CeO2 thin buffer layers on Si support limited the reaction between support and thin films. No reactions were observed between the surface Al2O3 and MgO and thin films. (C) 2016 Elsevier Ltd. All rights reserved.

Background Genetic polymorphisms are known to influence milk production and composition. However, the genomic mechanisms involved in the genetic regulation of milk component synthesis are not completely understood. MicroRNAs (miRNAs) regulate gene expression. Previous research suggests that the high developmental potential of the mammary gland may depend in part on a specific miRNA expression pattern. The objective of the present study was to compare the mammary gland miRNomes of two dairy cow breeds, Holstein and Montbéliarde, which have different mammogenic potentials that are related to differences in dairy performance. Results Milk, fat, protein, and lactose yields were lower in Montbéliarde cows than in Holstein cows. We detected 754 distinct miRNAs in the mammary glands of Holstein (n = 5) and Montbéliarde (n = 6) midlactating cows using RNA-Seq technology, among which 738 were known and 16 were predicted miRNAs. The 25 most abundant miRNAs accounted for 90.6% of the total reads. The comparison of their abundances in the mammary glands of Holstein versus Montbéliarde cows identified 22 differentially expressed miRNAs (Padj ≤ 0.05). Among them, 11 presented a fold change ≥2, and 2 (miR-100 and miR-146b) were highly expressed. Among the most abundant miRNAs, miR-186 is known to inhibit cell proliferation and epithelial-to-mesenchymal transition. Data mining showed that 17 differentially expressed miRNAs with more than 20 reads were involved in the regulation of mammary gland plasticity. Several of them may potentially target mRNAs involved in signaling pathways (such as mTOR) and lipid metabolism, thereby indicating that they could influence milk composition. Conclusion We found differences in the mammary gland miRNomes of two dairy cattle breeds. These differences suggest a potential role for miRNAs in mammary gland plasticity and milk component synthesis, both of which are related to milk production and composition. Further research is warranted on the genetic regulation of miRNAs and their role in milk synthesis. Electronic supplementary material The online version of this article (10.1186/s12864-019-5987-4) contains supplementary material, which is available to authorized users.

National audience; Les microARN (miARNs) sont de petits ARNs non codants régulant l'expression génique au niveau posttranscriptionnel. Ils sont synthétisés par les cellules et sont aussi présents dans les fluides physiologiques tels que le lait, dans les vésicules extracellulaires ainsi que dans les globules gras qui sont sécrétés en grande quantité dans le lait. Si l’on considère que les miARNs contenus dans les globules gras du lait sont majoritairement le reflet de ceux du tissu mammaire, le profil de certains diffère. Ceci pose la question de l’origine des miARNs présents dans les globules gras ainsi que de leur mode de sécrétion. L'objectif de la présente étude pilote était d'évaluer l'existence d'un possible mécanisme de tri des miARNs produits par la cellule épithéliale mammaire (CEM) et de leur export ou non via les globules gras du lait. Pour cela, 12 vaches en lactation ont permis la collecte de glande mammaire (n=6) et de lait (n=6). Trois préparations de CEM, capturées par microdissection laser, ont été effectuées. Quatre miARNs (miR-125b-5p, miR-126-3p, miR-141-3p et miR-204-5p) ont été choisis sur la base de leur abondance différente dans le lait et dans le tissu mammaire. Après extraction des ARN totaux (kit miRVana), les miARNs ont été quantifiés par RTqPCR (kits TaqMan® MicroRNA Reverse Transcription et TaqMan® Advanced miRNA cDNA synthesis + TaqMan® Fast Advanced Master Mix) dans le tissu mammaire (parenchyme sécrétoire profond), dans la matière grasse du lait, et les CEM microdisséquées. Deux miARNs (miR-125b-5p et miR-141-3p) ont été détectés dans le tissu mammaire, la matière grasse et les CEM, tandis que miR-204-5p n'a été détecté que dans le tissu mammaire. Cela suggère que ce miARN pourrait être exprimé dans un type cellulaire mammaire autre que les CEM, par exemple les cellules myoépithéliales, immunitaires ou les adipocytes mammaires. Le résultat le plus intéressant concerne miR-126-3p qui a été détecté dans le tissu mammaire, les CEM, mais pas dans la matière grasse du lait, ce qui suggère une localisation différente ou un possible mécanisme d'adressage des miARNs vers les voies de sécrétion ou non dans les CEM. En conclusion, cette étude pilote met en évidence des différences qualitatives de contenu en miARNs entre les CEM et la matière grasse laitière. Ces résultats laissent penser qu’il existerait un mécanisme non aléatoire de chargement des miARNs dans les globules gras, à l'image des processus de tri décrits pour les vésicules extracellulaires. Ce mécanisme reste à élucider pour ce qui concerne les globules gras.

To produce embryos by nuclear transfer, it needs a great epigenetic reprogramming of somatic nucleus into embryonic nucleus: this reprogramming is highly dependent of oocyte capacity. Thus, each nucleus is placed in a different environment as soon as the oocyte-somatic cell fusion. This way, the cloned animals obtained using the same fibroblast line, have the same nuclear genotype, but are indubitably epigenetically different ([1]). DNA methylation, is one of the more important epigenetic modification analyzed contributes play a role in regulating gene expression and consequently in different biological processes, such as those involved in health and disease. In this study, we analyzed the genome-wide DNA methylation of a purified subpopulation of immune cells, such as monocytes from cloned and controls Holstein (n=5 per group). Born in an experimental INRA’s farm the cows were breed exactly under the same conditions limiting environmental changes. All growth, health and reproductive information has been collected. Cows were hormonally synchronized, the ovulation detected by ultrasonography and blood samples collected at D15 of cycle. Monocyte purification was performed from peripheral blood mononuclear cells obtained by Ficoll gradient, using CD14+ antibody beads. Genome-wide DNA methylation was analyzed by Reduced Representation Bisulfite Sequencing (RRBS; [2]). After sequencing, the reads were analyzed using our dedicated pipeline (https://github.com/FAANG/faang-methylation/tree/master/RRBS-toolkit). After mapping to the reference genome (UMD3.1 assembly), around of 40% of uniquely mapped reads were obtained. Only CpGs covered between 10X and 500X were analyzed and used to calculate a DNA methylation score which was not different between cloned and control groups. However, PCA described a clear separation between cloned and control groups. Differential analysis of the 10 libraries provided differentially methylated cytosine (DMCs) between the two groups, corresponding to DMRs. This study therefore highlights CpGs and regions displaying a specific methylation pattern in cloned cows.

The expression of Azgp1 gene, an adipokine involved in the mobilization of body reserves, was observed in mammary gland of ruminants. Its regulation by different dietary conditions suggests a potential role in the mechanisms controlling the composition of milk fat. The aim of this study was to evaluate the role of Azgp1 during lactation. Azgp1

The catalytic efficiency of ternary strontium cerium tungstate Sr0.5Ce0.35WO4, for the production of syngas through methane oxidation, was investigated and compared to those of binary strontium tungstate SrWO4. Total and partial oxidation reactions were observed for both samples in the temperature range 600–750 °C under CH4/dry air flux. At high CH4 concentration and low temperature with the ternary tungstate as catalyst, the partial oxidation, leading to CO/H2, prevails. This indicates the potentiality of the new strontium cerium tungstate scheelite compound for the catalysis of CH4. Sr0.5Ce0.35WO4 and SrWO4 exhibit different conduction mechanisms. Conduction in the binary compound is related to the overlapping large polaron tunneling model, whereas conduction in the ternary one is due to a correlated barrier hopping phenomenon. The activation energies, in the low temperature range where the partial oxidation occurs, are significantly lower for the ternary compound than for the binary one. These electrical tendencies favor both partial and total oxidation of methane. The correlated barrier hopping conduction in the ternary compound leads to a better partial oxidation rate than conduction through large polaron tunneling.

International audience; The objective was to assess effects of experimentally induced undernutrition on responses to an intramammary lipopolysaccharide (LPS) challenge in early-lactation cows. Starting at 24 +/- 3 d in milk, multiparous Holstein cows either received a ration containing 48% straw for 96 h to restrict nutrient intake (REST, n = 8) or were allowed ad libitum intake of a lactation diet (CONT, n = 9). After 72 h on diet or after an equivalent period for CONT, 50 mu g of LPS (Escherichia coli 0111:B4) was injected into one healthy rear mammary quarter to induce an acute inflammation response. Blood samples were collected weekly until 7 wk of lactation, daily during feed restriction (or control), before and at 1, 2, 4, 6, 10, and 24 h relative to LPS injection. Foremilk quarter samples were collected before and at 4, 6, 10, and 24 h after LPS injection. Dry matter intake, milk yield, energy balance, plasma glucose, nonesterifled fatty acids (NEFA), and beta-hydroxybutyrate (BHB) concentrations did not differ between CONT and REST immediately before nutrient restriction in REST (least squares means at d -1 were 21.8, 39.0 kg/d, -2.5 MJ/d, and 3.78, 0.415, 0.66 mM, respectively) but were significantly altered at 72 h of nutrient restriction (9.8, 28.3 kg/d, -81.6 MJ/d, and 2.77, 1.672, and 2.98 mM, respectively), when the LPS challenge was performed. The rectal temperature increment from baseline values in response to LPS did not differ, but cortisol increment was greater and cortisol response area under the curve (AUC) tended to be greater [202 vs. 122 (ng/mL) x 10 h] for REST than CONT. No treatment differences were observed in foremilk IL-8, IL-1 beta, tumor necrosis factor-alpha, and chemokine (C-X-C motif) ligand 3 concentrations in response to LPS injection. Composite milk somatic cell count per milliliter (6.919 x 10(6) vs. 1.956 x 10(6) cells/mL) and total number of somatic cells secreted in milk per day were greater for REST than CONT during the day following LPS. Plasma glucose, urea, and insulin concentrations increased after the LPS challenge, suggesting establishment of insulin resistance and modifications of glucose metabolism to support acute inflammation in both CONT and REST. Nonetheless, nutrient-restricted cows had delayed plasma insulin and glucose responses to LPS, smaller insulin AUC but greater glucose AUC compared with CONT, despite the limited nutrient availability to sustain an inflammation response. Undernutrition altered peripheral metabolic responses to an intramammary LPS challenge but had limited effects on selected indicators of inflammation response in early-lactation cows.

Background: Fatty acid (FA) composition plays a crucial role in milk nutritional quality. Despite the known nutritional regulation of ruminant milk composition, the overall mammary mechanisms underlying this regulation are far from being understood. The aim of our study was to determine nutritional regulation of mammary transcriptomes in relation to the cow milk composition. Methods: Twelve cows received diets differing in the forage-to-concentrate ratio [high forage (HF) and low forage (LF)] supplemented or not with lipids [HF with whole intact rapeseeds (RS) and LF sunflower oil (SO)] in a 4 × 4 Latin square design. Milk production and FA composition were determined. The gene expression profile was studied using RT-qPCR and a bovine microarray. Results: Our results showed a higher amplitude of milk composition and mammary transcriptome responses to lipid supplementation with the LF-SO compared with the LF diet than with the HF-RS compared with the HF diet. Forty-nine differentially expressed genes, including genes involved in lipid metabolism, were identified with LF-SO versus LF, whereas RS supplementation to the HF diet did not affect the mammary transcriptome. Conclusions: This study highlights different responses to lipid supplementation of milk production and composition and mammary transcriptomes depending on the nature of lipid supplementation and the percentage of dietary concentrate.

International audience; Nutrition is a major factor that regulates ruminant milk components, particularly its fatty acid (FA) composition, which is an important determinant of milk nutritional quality. In the mammary gland, milk component biosynthesis involves a large number of genes under nutritional regulation that are not well understood. Thus, the objective of the present study was to evaluate the effects of extruded linseeds (EL) alone or in combination with fish oil (ELFO) on goat mammary gene expression. In total, 14 goats were fed one of the following three diets: a natural grassland hay basal diet (CTRL) alone, CTRL supplemented with 530 g/day of EL, or 340 g/day of EL plus 39 g/day of fish oil (ELFO). Mammary secretory tissues were collected after slaughter on day 28, to determine the expression of 14 lipogenic genes and five lipogenic enzyme activities and transcriptomic profiles. The mRNA abundance decreased for SCD1 ( P

Molecular nutrition is relatively recent research discipline that aims to decipher molecular effects of nutrition at the cellular level and identify mechanisms underlying potential impact on health, protective or deleterious. The development and the use of holistic “omics” approach in the last decade or two have revealed the complexity of action of different nutrients at the molecular level. These nutrigenomic studies have shown that nutrients can impact transcriptional and post transcriptional regulation of gene expression, by impacting expression of mRNA, non-coding RNAs (both short and long) and proteins, but also modulate epigenetic profile of the cells. The capacity of nutrients to exert these nutrigenomic effects can be related to the their ability to bind to cell signaling proteins, modulate their activity and consequently that of transcription factors. The feature article gives a rapid overview of molecular mechanisms impacted by different nutrients.

International audience; Based on the potential benefits for long-term human health, there is interest in developing sustainable nutritional strategies for lowering medium-chain saturated fatty acids (FA) and increasing specific unsaturated FA in ruminant milk. Dietary supplements of extruded linseeds (EL), fish oil (FO) or a mixture of EL and FO increase cis-9,trans-11 CLA and long-chain n-3 polyunsaturated FA in bovine milk. Supplements of FO cause milk fat depression in lactating cows, but information for dairy goats is limited. A total of 14 Alpine goats were used in a replicated 3×3 Latin square with 28-days experimental periods to examine the effects of EL alone or in combination with FO on animal performance, milk fat synthesis and milk FA composition. Treatments comprised diets based on natural grassland hay supplemented with no additional oil (control), 530 of EL or 340 g/day of EL and 39 g/day of FO (ELFO). Compared with the control, ELFO tended (P=0.08) to lower milk fat yield, whereas EL increased (P

Nano-octahedra of cobalt ferrite Co x Fe3 − xO4 (1 ≤ x

International audience; Synopsis-A new ternary scheelite tungstate (Sr,Ce)WO 4 phase was synthesized, with a 2D incommensurately modulated structure linked to partial ordering of Sr, Ce cations and vacancies as was evidenced by high resolution electron microscopy. The bang gap of 3.2 eV makes it a promising violet emitting compound. Abstract-type the Abstract here (Style: IUCr Abstract) For the first time, a ternary tetragonal scheelite structure tungstate with strontium and cerium cations,(Sr,Ce)WO 4 , was synthesized. As much as 35 % Ce could be inserted in the structure, leaving 1/7 of the (Sr,Ce) cation sites vacant. Partial ordering of Sr and Ce, with atomic displacements, were evidenced by high resolution electron microscopy. 2D incommensurate modulations occur in this material, in small domains 20 nm in size. The band gap of this compound is significantly lower than the band gap of SrWO 4 and this was related to the distortions of WO 4 and (Sr,Ce)O 8 polyhedra. The bang gap value of 3.2 eV makes Sr 1/2 Ce 5/14 □ 1/7 WO 4 a promising candidate for violet luminescence.

La santé et la fertilité des vaches laitières sont au cœur des préoccupations de la filière professionnelle dans un objectif d’efficience, de quantité et de qualité de la production de lait. La mise en place d’une lactation performante se superpose aux profonds changements hormonaux et métaboliques de la période postpartum, se traduisant par une balance énergétique négative. Les conséquences en sont souvent une altération de la fertilité et une immunodépression qui accroit la susceptibilité aux pathologies. Dans les élevages, il existe encore une grande variabilité d’état général et de performances chez les vaches laitières malgré la sélection génomique. Il est proposé que des modifications de la méthylation de l’ADN puissent contribuer à cette variabilité phénotypique individuelle. En effet, la méthylation de l’ADN, en tant que processus épigénétique, est impliquée dans la régulation transcriptionnelle des gènes, et présente une certaine plasticité face aux contraintes environnementales. Nous avons fait l’hypothèse que des signatures épigénétiques portées par les cellules du sang, pourraient refléter l’état de santé des vaches et pourraient être modifiées en réponse à différents facteurs intrinsèques (parité, stades physiologiques…) et aux contraintes environnementales. Ces signatures ont été recherchées dans une population de cellules du sang particulière : les monocytes. Ces cellules, accessibles par prélèvements sanguins et purification en présence d’un anticorps spécifique, constituent la première ligne de réponse d’immunité innée face aux infections aigües participant à la dégradation de l’état de santé des vaches en postpartum. Pour tester l’hypothèse de signatures épigénétiques monocytaires, une analyse du méthylome par « Reduced Representation Bisulfite Sequencing », (RRBS) dans diverses situations d’élevage a été réalisée. En utilisant des ADN génomiques de vaches incluses dans plusieurs protocoles, 22 banques ont été construites et séquencées. Leur analyse a été réalisée en utilisant un pipeline d’analyses bioinformatique et biostatistique développé au laboratoire. En moyenne 1 250 000 CpG sont pris en considération et permettent l’identification et la localisation de cytosines différentiellement méthylées (DMC) : i) 27143 DMC en comparant les méthylomes de différents types cellulaires (monocytes versus fibroblastes et PBMC) ii) 4788 DMC en réponse à un challenge nutritionnel basé sur la distribution du complément alimentaire GENIAL®, fabriqué et distribué en élevage par nos partenaires PILARDIERE et XR-Repro. iii) 2615 et 4616 DMC en réponse au challenge infectieux pour le groupe de vaches témoins et le groupe en restriction alimentaire respectivement (protocole coordonné par Christine Leroux et José Pires (RUMINFLAME, INRA, Theix) combinant une restriction alimentaire et un challenge immunitaire, par injection de LipoPolySaccharide). iv) 4420 DMC issues de la comparaison entre méthylomes de vaches à génome constant (issues du transfert nucléaire, clones) et de vaches à génome variable mais de même âge et élevées dans les mêmes conditions que les clones. Pour certaines régions différentiellement méthylées (DMR) ciblant le promoteur de gènes, le statut de méthylation a été confirmé par conversion bisulfite et pyroséquençage. L’expression des gènes associés a été étudiée. Une anti corrélation significative est observée entre méthylation et expression signant la fonctionnalité de ces régions. En comparant les 11 méthylomes monocytaires, il est montré que 21% des CpG sont extrêmement stables et ne présentent qu’une faible variation de méthylation entre échantillons ( 20%).L’ensemble de ces informations peut être pris en considération pour la conception d’un outil d’épigénotypage. A l’avenir, il serait aussi possible d’utiliser cet outil en routine afin d’appréhender les variations du méthylome monocytaire dans différentes conditions d’élevage.

The electrical response of cobalt ferrites CoxFe3-xO4 nanopowders was tested in presence of ammonia. The morphology, shape and chemical composition of the powder was fully characterized by transmission electron microscopy. Fast response, good sensitivity and good reversibility were evidenced, with detection even at 5 ppm NH3. Gas selectivity depends on the cobalt amount, x, in cobalt ferrite powders.

In this work, we report the synthesis of SrWO 4 (SWO) and Ce 2 (WO 4 ) 3 (CWO) phases, based on the ethylenediaminetetraacetic–citrate complexing method. All samples were characterized by thermogravimetric analysis, X-ray diffraction and electron microscopy to identify the structure and the morphology of each compound. The catalytic reactivity of the samples was analyzed using a homemade reactor coupled to a combined system of Fourier transform infrared spectrometer (FTIR) and mass spectrometer apparatus. The measurements were performed under methane gas flows with different gas carriers (Air and Argon), in the temperature range of 500–950 °C. The catalytic activity was determined as a function of time and temperature. In specific circumstances, FTIR experiments show that methane is partly oxidized into CO thus giving rise to syngas production at low pressure. The reactivity could be linked to oxygen species delivered by solids. Electrical impedance spectroscopy analyses have been carried out on compacted polycrystalline samples, and Nyquist representations have been interpreted. The SWO and CWO samples presented similar semiconducting behaviors with electronic and ionic mix conductions, with higher conductivity for the CWO phase.

International audience; Gold-free GaAs nanowires on silicon substrates can pave the way for monolithic integration of photonic nanodevices with silicon electronic platforms. It is extensively documented that the self-catalyzed approach works well in molecular beam epitaxy but is much more difficult to implement in vapor phase epitaxies. Here, we report the first gallium-catalyzed hydride vapor phase epitaxy growth of long (more than 10 mu m) GaAs nanowires on Si(111) substrates with a high integrated growth rate up to 60 mu mh(-1) and pure zincblende crystal structure. The growth is achieved by combining a low temperature of 600 degrees C with high gaseous GaCl/As flow ratios to enable dechlorination and formation of gallium droplets. GaAs nanowires exhibit an interesting bottle-like shape with strongly tapered bases, followed by straight tops with radii as small as 5 nm. We present a model that explains the peculiar growth mechanism in which the gallium droplets nucleate and rapidly swell on the silicon surface but then are gradually consumed to reach a stationary size. Our results unravel the necessary conditions for obtaining galliumcatalyzed GaAs nanowires by vapor phase epitaxy techniques.

Mammary gland is the organ of milk component synthesis that provides the nutrients for growth and development of the mammalian neonate. In addition to macronutrients like proteins, carbohydrates, and lipids known for their roles in providing substrate and energy, a new class of components has been identified notably microRNA that have signaling roles regulating a large set of biological processes. MicroRNAs, short noncoding RNAs, have been reported to act on the mammary tissues, influencing mammary development and milk component biosynthesis, and evidence is now assembling that they also signal to the infant. The expression profile of these miRNAs can be under nutritional regulation. Their presence in milk and their relative persistency through industrial treatment open new way of investigations to use them as biomarkers of animal health, as well as to evaluate their effects on the health of those consuming them. Due to the role of miRNAs on human health and diseases, their transfer from milk or milk products to infants and adults is being actively researched, though their bioavailability is not known. Research is defining their distribution in the different fractions of milk (such as cells, exosomes, fat globule, or skim milk). Indeed, the unique packaging of miRNAs could be crucial for their action through the intestinal tract. The value of milk miRNAs to diverse aspects of human health is now an emerging field of science

Mammary gland is the organ of milk component synthesis that provides the nutrients for growth and development of the mammalian neonate. In addition to macronutrients like proteins, carbohydrates, and lipids known for their roles in providing substrate and energy, a new class of components has been identified notably microRNA that have signaling roles regulating a large set of biological processes. MicroRNAs, short noncoding RNAs, have been reported to act on the mammary tissues, influencing mammary development and milk component biosynthesis, and evidence is now assembling that they also signal to the infant. The expression profile of these miRNAs can be under nutritional regulation. Their presence in milk and their relative persistency through industrial treatment open new way of investigations to use them as biomarkers of animal health, as well as to evaluate their effects on the health of those consuming them. Due to the role of miRNAs on human health and diseases, their transfer from milk or milk products to infants and adults is being actively researched, though their bioavailability is not known. Research is defining their distribution in the different fractions of milk (such as cells, exosomes, fat globule, or skim milk). Indeed, the unique packaging of miRNAs could be crucial for their action through the intestinal tract. The value of milk miRNAs to diverse aspects of human health is now an emerging field of science