In Vitro Fertilization and Embryo Culture Strongly Impact the Placental Transcriptome in the Mouse Model

BACKGROUND: Assisted Reproductive Technologies (ART) are increasingly used in humans; however, their impact is now questioned. At blastocyst stage, the trophectoderm is directly in contact with an artificial medium environment, which can impact placental development. This study was designed to carry out an in-depth analysis of the placental transcriptome after ART in mice. METHODOLOGY/PRINCIPAL FINDINGS: Blastocysts were transferred either (1) after in vivo fertilization and development (control group) or (2) after in vitro fertilization and embryo culture. Placentas were then analyzed at E10.5. Six percent of transcripts were altered at the two-fold threshold in placentas of manipulated embryos, 2/3 of transcripts being down-regulated. Strikingly, the X-chromosome harbors 11% of altered genes, 2/3 being induced. Imprinted genes were modified similarly to the X. Promoter composition analysis indicates that FOXA transcription factors may be involved in the transcriptional deregulations. CONCLUSIONS: For the first time, our study shows that in vitro fertilization associated with embryo culture strongly modify the placental expression profile, long after embryo manipulations, meaning that the stress of artificial environment is memorized after implantation. Expression of X and imprinted genes is also greatly modulated probably to adapt to adverse conditions. Our results highlight the importance of studying human placentas from ART

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

A multi-scale analysis of bull sperm methylome revealed both species peculiarities and conserved tissue-specific

peer-reviewedBackground: Spermatozoa have a remarkable epigenome in line with their degree of specialization, their unique nature and different requirements for successful fertilization. Accordingly, perturbations in the establishment of DNA methylation patterns during male germ cell differentiation have been associated with infertility in several species.Background: Spermatozoa have a remarkable epigenResults: The quantification of DNA methylation at CCGG sites using luminometric methylation assay (LUMA) highlighted the undermethylation of bull sperm compared to the sperm of rams, stallions, mice, goats and men. Total blood cells displayed a similarly high level of methylation in bulls and rams, suggesting that undermethylation of the bovine genome was specific to sperm. Annotation of CCGG sites in different species revealed no striking bias in the distribution of genome features targeted by LUMA that could explain undermethylation of bull sperm. To map DNA methylation at a genome-wide scale, bull sperm was compared with bovine liver, fibroblasts and monocytes using reduced representation bisulfite sequencing (RRBS) and immunoprecipitation of methylated DNA followed by microarray hybridization (MeDIP-chip). These two methods exhibited differences in terms of genome coverage, and consistently, two independent sets of sequences differentially methylated in sperm and somatic cells were identified for RRBS and MeDIP-chip. Remarkably, in the two sets most of the differentially methylated sequences were hypomethylated in sperm. In agreement with previous studies in other species, the sequences that were specifically hypomethylated in bull sperm targeted processes relevant to the germline differentiation program (piRNA metabolism, meiosis, spermatogenesis) and sperm functions (cell adhesion, fertilization), as well as satellites and rDNA repeats. Conclusions: These results highlight the undermethylation of bull spermatozoa when compared with both bovine somatic cells and the sperm of other mammals, and raise questions regarding the dynamics of DNA methylation in bovine male germline. Whether sperm undermethylation has potential interactions with structural variation in the cattle genome may deserve further attention. While bull semen is widely used in artificial insemination, the literature describing DNA methylation in bull spermatozoa is still scarce. The purpose of this study was therefore to characterize the bull sperm methylome relative to both bovine somatic cells and the sperm of other mammals through a multiscale analysis

Photoproduction de pions neutres au voisinage du seuil sur les noyaux d'helium-4, de carbone-12 et de calcium-40

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Regards croisés sur les feuilles de route hydrogène de trois pays : le Canada, le Japon et la France. Quels enseignements ?

Les multiples usages de l’hydrogène – moyen de stockage de l’énergie, utilisation finale pour la mobilité ou la production d’électricité et de chaleur, vecteur de couplage des réseaux – en font un vecteur clé de la transition énergétique. De nombreux pays et territoires s’engagent ainsi dans une feuille de route hydrogène, avec pour objectif une progressive décarbonation de leur système énergétique. L’analyse de la trajectoire de déploiement des technologies de l’hydrogène au Canada, au Japon et en France, montre que le succès de ces initiatives dépend de plusieurs ensembles de conditions : 1 ) une contribution claire et argumentée à l’effort de transition énergétique et un soutien politique ; 2) des activités nationales de R&D, de démonstration et d’industrialisation, préparant le déploiement, soutenu par des mécanismes financiers appropriés ; 3) un engagement de toutes les parties prenantes dans les débats sur le rôle de l’hydrogène dans la transition énergétique, ainsi que dans la définition et la réalisation des projets locaux de déploiement.The multiple uses of hydrogen – as a mean to store energy, for mobility or cogeneration of electricity and heat, as a vector to bridge between energy networks – make it a key vector of the energy transition. Many countries and regions are thus embarking on a hydrogen roadmap, with the objective of a progressive decarbonization of their energy system. The analysis of hydrogen technologies deployment trajectories – in Canada, Japan and France – shows that the success of these initiatives depends on several sets of conditions : 1) a clear and well-argued contribution to the energy transition effort, associated with strong political support ; 2) national R&D, demonstration and industrialization activities, preparing for deployment, and supported by appropriate financial mechanisms ; 3) engagement of all stakeholders in the debates on the role of hydrogen in the energy transition, as well as in the definition and implementation of local deployment projec

Intérêt de l'utilisation d'outils de mesures simples pour évaluer la composition corporelle dans une population de jeunes sportifs (pratique en médecine générale)

OBJECTIF: Démontrer que la mesure de la masse grasse (MG) par la méthode des plis cutanés et du tour de taille (TT) sont facilement utilisables en médecine générale et vérifier que l'indice de masse corporelle (IMC) est inadapté dans une population sportive en comparaison du taux de MG, de sa répartition, des performances sportives. METHODES: des mesures anthropométriques ont été réalisées chez 294 militaires, sportifs réguliers. Un questionnaire a évalué le niveau sportif (test Cooper), d éventuels problèmes dus au surpoids. RESULTATS: Pour des 25 = 19% par la méthode des plis cutanés) et une adiposité abdominale élevée (TT>94 cm) étaient mauvaises (VPP=0,43 et VPP = 0,45). Tous les IMC >= 30kg.m avaient un taux de MG >= 19% et une TT >= 94 cm. L'IMC n'était pas lié aux performances sportives car 58,0% des sujets qui avaient un IMC= 3000m contre 44,4% des sujets qui avaient un IMC >= 25kg.m (p=0,045). Le taux de MG mesuré par la méthode des plis cutanés et le TT étaient liés aux performances sportives: 84,6% des sujets qui avaient un taux de MG >= 19% et 82% des patients avec un TT > 94 cm faisaient <3000m contre 36,1% des sujets avec un taux de MG<19% et 37,3% des sujets avec un TT <= 94 cm (p<0,0001). 5 sujets avaient fait des régimes pour éviter de perdre une aptitude professionnelle car leur IMC était élevé alors que leur taux de MG était <19% et leur TT<94 cm. CONCLUSION: l'IMC est peu adapté pour des jeunes sportifs. D'autres moyens simples de mesure peuvent aisément s'intégrer dans une visite médicale: la méthode des plis cutanés et la mesure du TT.AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-Bib. Serv.Santé Armées (751055204) / SudocSudocFranceF

Low-Power Embedded Audio Recording using MEMS Microphones

International audienceThis paper introduces the design of a low-power and low-cost audio recorder. Although the initial purpose is the study of wildlife behavior, the result can be applied to many other fields including urban noise cartography or industrial monitoring. The system is based on a minimal set of low-cost, off-the-shelf components (MEMS microphone, microcontroller, and SD card). Focus is given to autonomy both in terms of embedded energy and data storage. The paper demonstrates that both are improved by applying an online embedded compression to the audio data. Together with an ingenious use of available hardware resources, we were able to lower the overall power consumption compared to existing solutions by an order of magnitude, at equivalent audio quality

Sperm-borne sncRNAs: potential biomarkers for semen fertility?

International audienceSemen infertility or sub-fertility, whether in humans or livestock species, remains a major concern for clinicians and technicians involved in reproduction. Indeed, they can cause tragedies in human relationships or have a dramatic overall negative impact on the sustainability of livestock breeding. Understanding and predicting semen fertility issues is therefore crucial and quality control procedures as well as biomarkers have been proposed to ensure sperm fertility. However, their predictive values appeared to be too limited and additional relevant biomarkers are still required to diagnose sub-fertility efficiently. During the last decade, the study of molecular mechanisms involved in spermatogenesis and sperm maturation highlighted the regulatory role of a variety of small non-coding RNAs (sncRNAs) and led to the discovery that sperm sncRNAs comprise both remnants from spermatogenesis and post-testicular sncRNAs acquired through interactions with extracellular vesicles along epididymis. This has led to the hypothesis that sncRNAs may be a source of relevant biomarkers, associated either with sperm functionality or embryo development. This review aims at providing a synthetic overview of the current state of knowledge regarding implication of sncRNA in spermatogenesis defects and their putative roles in sperm maturation and embryo development, as well as exploring their use as fertility biomarkers

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Addressing Power Issues in Biologging: An Audio/Inertial Recorder Case Study

International audienceIn the past decades, biologging, i.e., the development and deployment of animal-borne loggers, has revolutionized ecology. Despite recent advances, power consumption and battery size however remain central issues and limiting factors, constraining the quantity of data that can be collected and the size of the animals that can be studied. Here, we present strategies to achieve ultra-low power in biologging, using the design of a lightweight audio-inertial logger as an example. It is designed with low-power MEMS sensors, and a firmware based on a small embedded RTOS. Both methodologies for power reduction and experimental results are detailed. With an average power consumption reduced to 5.3 mW, combined with a battery of 1800 mAh, the logger provides 900 h of continuous 8 kHz audio, 50 Hz accelerometer and 10 Hz magnetometer data