Autophagy, a Highly Regulated Intracellular System Essential to Skeletal Muscle Homeostasis — Role in Disease, Exercise and Altitude Exposure

Autophagy is an evolutionarily conserved intracellular system that selectively eliminates protein aggregates, damaged organelles, and other cellular debris. It is a self-cleaning process critical for cell homeostasis in conditions of energy stress. Autophagy has been until now relatively overlooked in skeletal muscle, but recent data highlight its vital role in this tissue in response to several stress conditions. The most recognized sensors for autophagy modulation are the adenosine monophosphate (AMP)-activated protein kinase (AMPK) and the mechanistic target of rapamycin (MTOR). AMPK acts as a sensor of cellular energy status by regulating several intracellular systems including glucose and lipid metabolisms and mitochondrial biogenesis. Recently, AMPK has been involved in the control of protein synthesis by decreasing MTOR activity and in the control of protein breakdown programs. Concerning proteolysis, AMPK notably regulates autophagy through FoxO transcription factors and Ulk1 complex. In this chapter, we describe the functioning of the different autophagy pathways (macroautophagy, microautophagy, and chaperone-mediated autophagy) in skeletal muscle and define the role of macroautophagy in response to physical exercise, a stress that is well assumed to be a key strategy to counteract metabolic and muscle diseases. The effects of dietary factors and altitude exposure are also discussed in the context of exercise

Ground-based Characterization of Hayabusa2 Mission Target Asteroid 162173 Ryugu: Constraining Mineralogical Composition in Preparation for Spacecraft Operations

Asteroids that are targets of spacecraft missions are interesting because they present us with an opportunity to validate ground-based spectral observations. One such object is near-Earth asteroid (NEA) (162173) Ryugu, which is the target of the Japanese Space Agency's (JAXA) Hayabusa2 sample return mission. We observed Ryugu using the 3-m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii, on July 13, 2016 to constrain the object's surface composition, meteorite analogs, and link to other asteroids in the main belt and NEA populations. We also modeled its photometric properties using archival data. Using the Lommel-Seeliger model we computed the predicted flux for Ryugu at a wide range of viewing geometries as well as albedo quantities such as geometric albedo, phase integral, and spherical Bond albedo. Our computed albedo quantities are consistent with results from Ishiguro et al. (2014). Our spectral analysis has found a near-perfect match between our spectrum of Ryugu and those of NEA (85275) 1994 LY and Mars-crossing asteroid (316720) 1998 BE7, suggesting that their surface regoliths have similar composition. We compared Ryugu's spectrum with that of main belt asteroid (302) Clarissa, the largest asteroid in the Clarissa asteroid family, suggested as a possible source of Ryugu by Campins et al. (2013). We found that the spectrum of Clarissa shows significant differences with our spectrum of Ryugu, but it is similar to the spectrum obtained by Moskovitz et al. (2013). The best possible meteorite analogs for our spectrum of Ryugu are two CM2 carbonaceous chondrites, Mighei and ALH83100.Comment: 23 pages, 7 figures, 4 tables, accepted in Monthly Notices of the Royal Astronomical Society Main Journa

Toward a Play Management System for Play-Based Learning

International audienceThis position paper is dedicated to describing a preliminary model of an integrated system, called Play Management System (PMS). PMS is designed to support both players and teachers to deliver, use, manage and track play situations. This PMS model results from a design-based research methodology. Our approach focuses on (1) the learners and the situation that emerges when they play the game, rather than the system dedicated to play and (2) the teachers who want to manage a game-based learning situation. Thus, we argue for a shift from a game-based to a play-based perspective. 1 Introduction Within a context marked by the development of alternative pedagogies, this position paper aims to describe a model of an integrated system, called Play Management System (PMS), dedicated to support players and teachers to deliver, use, manage and track play situations. The purpose of this article is to propose an innovative approach for implementing a play-based learning approach by (1) focusing on the learners and taking into consideration the situation that emerges when they play rather than the artifact dedicated to play (play vs game) and (2) focusing on the teachers who want to implement and manage a play-based learning situation in their classroom (play management vs game design). Thus, we address the issue of teachers' requirements for the orchestration of a play situation within an educational context. In the first section of this paper, we advocate for a player-centered approach for game-based learning. The second section presents a game developed during the project and the design-based research methodology adopted for designing this game. The third section describe

Physical Characterization of Active Asteroid (6478) Gault

Main belt asteroid (6478) Gault has been dynamically linked with two overlapping asteroid families: Phocaea, dominated by S-type asteroids, and Tamara, dominated by low-albedo C-types. This object has recently become an interesting case for study, after images obtained in late 2018 revealed that it was active and displaying a comet-like tail. Previous authors have proposed that the most likely scenarios to explain the observed activity on Gault were rotational excitation or merger of near-contact binaries. Here we use new photometric and spectroscopic data of Gault to determine its physical and compositional properties. Lightcurves derived from the photometric data showed little variation over three nights of observations, which prevented us from determining the rotation period of the asteroid. Using WISE observations of Gault and the near-Earth Asteroid Thermal Model (NEATM) we determined that this asteroid has a diameter $<$6 km. NIR spectroscopic data obtained with the Infrared Telescope Facility (IRTF) showed a spectrum similar to that of S-complex asteroids, and a surface composition consistent with H chondrite meteorites. These results favor a compositional affinity between Gault and asteroid (25) Phocaea, and rules out a compositional link with the Tamara family. From the spectroscopic data we found no evidence of fresh material that could have been exposed during the outburst episodes.Comment: 9 pages, 4 figures, accepted for publication in ApJ

Another Chapter in the History of the European Invasion by the Western Conifer Seed Bug, Leptoglossus occidentalis: The Iberian Peninsula

The Western conifer seed bug, Leptoglossus occidentalis, is native to North America and has already been considered a significant pest in several European countries since its first observation in Italy in 1999. In Spain and Portugal, it was recorded for the first time in 2003 and 2010, respectively, and its impact on Stone Pine (Pinus pinea) is of major concern. Before developing control measures for this insect pest, it is paramount to clarify its spatiotemporal dynamics of invasion. Therefore, in this study, we aimed to (a) characterise the genetic structure and diversity and (b) invasion pathways of L. occidentalis populations in the Iberian Peninsula. To do so, specimens of L. occidentalis were collected at fourteen sites widely distributed within the Iberian Peninsula. We used mtDNA sequences of Cytochrome b and eleven microsatellite markers to characterise the genetic diversity and the population structure in the Iberian Peninsula. Our genetic results combined with the observational dates strongly support a stratified expansion of L. occidentalis invasion in the Iberian Peninsula proceeding from multiple introductions, including at least one in Barcelona, one in Valencia, and one in the west coast or in the Southeastern region.Ana Farinha received support from Fundação para a Ciência e a Tecnologia I.P. (FCT-MCES) through a PhD scholarship (PD/BD/52403/2013). Manuela Branco is supported by the Forest Research Centre (CEF) (UIDB/00239/2020) and the Laboratory for Sustainable Land Use and Ecosystem Services—TERRA (LA/P/0092/2020) funded by FCT, Portugal. European Project H2020 “Adaptive breeding for productive, sustainable and resilient forests under climate change” (B4EST; grant agreement No. 773383). Cost action FP1203: European Non-Wood Forest Products Network (NWFPs), European Cooperation in Science and Technology (COST)

REARTH un exemple de Jeu Épistémique Numérique De la conception à l’expérimentation

National audienceRESUME : Cet article a pour objet de présenter le projet JEN.lab et le JEN REARTH ainsi que son expérimentation et les premiers enseignements que nous en avons tiré. Un des objectifs du projet JEN.lab lancé en 2013 et financé par l'Agence Nationale de la Recherche est de concevoir des jeux épistémiques numériques (JEN) expérimentés en conditions écologiques. Les JEN apparaissent comme une pédagogie alternative aux approches traditionnelles favorisant tant le développement de compétences que de savoirs strictement disciplinaires. Dans ce cadre, le jeu Rearth a été conçu et expérimenté en partenariat avec des enseignants du lycée Aristide Briand de Saint-Nazaire pour des classes de STI2D. Le but est de développer chez les élèves, des compétences dans différents domaines de la technologie, de l'architecture et du développement durable en proposant des JEN en tant que situations d'apprentissages ludiques et authentiques

Active Mobility – the New Health Trend in Smart Cities, or even More?

Active mobility (AM), including walking and cycling as single trips or in combination with public transport, has recently been promoted by health professionals – with WHO leading the way – to tackle health problems caused by physical inactivity. In fact only 1/3 of the European population is estimated to meet the minimum recommended levels of physical activity by the WHO of 30 minutes of moderate-intensity activity 5 times per week. Being aware that we spend between 70 to 80 min per day travelling and that 50% of all car trips (in Europe) are shorter than 5 km, active mobility has an enormous potential to get people more active. However, how is this knowledge of proven positive health effects of AM been taken into account – either by urban and transport planning authorities or by health administration? Is this „new health trend“ visible in strategies, cooperation or – what’s even more important – in implemented measures in smart cities? “Physical activity through sustainable transport approaches” (PASTA1)” is a European project addressing and analyzing the promising link between transport and health. It pursues an interdisciplinary approach involving scientists and leading experts from a range of disciplines, including (among others) transport and urban planning, public health, environmental sciences, climate change and energy, and transport economics. The overall aim of the project is to generate knowledge about the effects of AM in consideration of health effects. This paper reveals backgrounds and relationships between transport and health work in seven European case study cities (Antwerp, Barcelona, London, Örebro, Rome, Vienna and Zurich) based on workshops and stakeholder interviews conducted in PASTA. Considering cities‘ framework conditions (strategies and policies, infrastructure and other measures promoting AM etc.) and comparing stakeholders‘ perspectives bring out that cities have to struggle with similar barriers and challenges. Otherwise they take promising approaches and efforts towards sustainable and healthy urban development; increasing synergies between the health and transport sector seems to be one of the missing links between transport and health. Good practices and new ideas for transport planners and health experts are provided aiding to create livable conditions through well-planned infrastructure, a safe environment and attractive public space, awareness-raising activities and various broader policies – including the health policy. After all AM should not just be an ephemeral health trend, but common (health) practice

Retinoic acid receptor α as a novel contributor to adrenal cortex structure and function through interactions with Wnt and Vegfa signalling

International audiencePrimary aldosteronism (PA) is the most frequent form of secondary arterial hypertension. Mutations in different genes increase aldosterone production in PA, but additional mechanisms may contribute to increased cell proliferation and aldosterone producing adenoma (APA) development. We performed transcriptome analysis in APA and identified retinoic acid receptor alpha (RARα) signaling as a central molecular network involved in nodule formation. To understand how RARα modulates adrenal structure and function, we explored the adrenal phenotype of male and female Rarα knockout mice. inactivation of Rarα in mice led to significant structural disorganization of the adrenal cortex in both sexes, with increased adrenal cortex size in female mice and increased cell proliferation in males. Abnormalities of vessel architecture and extracellular matrix were due to decreased Vegfa expression and modifications in extracellular matrix components. On the molecular level, Rarα inactivation leads to inhibition of non-canonical Wnt signaling, without affecting the canonical Wnt pathway nor PKA signaling. Our study suggests that Rarα contributes to the maintenance of normal adrenal cortex structure and cell proliferation, by modulating Wnt signaling. Dysregulation of this interaction may contribute to abnormal cell proliferation, creating a propitious environment for the emergence of specific driver mutations in PA. Primary aldosteronism (PA) is the most common and curable form of secondary arterial hypertension, with prevalence estimations of up to 10% of cases in referred hypertensive patients, 4% of patients in primary care 1,2 and 20% of patients with resistant hypertension 3,4. Rapid diagnosis and treatment are important to prevent severe cardiovas-cular consequences of long term aldosterone exposure, which are independent of blood pressure levels and are du