Impaired Hepatic Vitamin A Metabolism in NAFLD Mice Leading to Vitamin A Accumulation in Hepatocytes

BACKGROUND & AIMS: Systemic retinol (vitamin A) homeostasis is controlled by the liver, involving close collaboration between hepatocytes and hepatic stellate cells (HSCs). Genetic variants in retinol metabolism (PNPLA3 and HSD17B13) are associated with non-alcoholic fatty liver disease (NAFLD) and disease progression. Still, little mechanistic details are known about hepatic vitamin A metabolism in NAFLD, which may affect carbohydrate and lipid metabolism, inflammation, oxidative stress and the development of fibrosis and cancer, e.g. all risk factors of NAFLD. METHODS: Here, we analyzed vitamin A metabolism in 2 mouse models of NAFLD; mice fed a high-fat, high-cholesterol (HFC) diet and Leptin(ob) mutant (ob/ob) mice. RESULTS: Hepatic retinol and retinol binding protein 4 (RBP4) levels were significantly reduced in both mouse models of NAFLD. In contrast, hepatic retinyl palmitate levels (the vitamin A storage form) were significantly elevated in these mice. Transcriptome analysis revealed a hyperdynamic state of hepatic vitamin A metabolism, with enhanced retinol storage and metabolism (upregulated Lrat, Dgat1, Pnpla3, Raldh's and RAR/RXR-target genes) in fatty livers, in conjunction with induced hepatic inflammation (upregulated Cd68, Tnf alpha, Nos2, Il1 beta, 11-6) and fibrosis (upregulated Colla1, Acta2, Tgf beta, Timp1). Autofluorescence analyses revealed prominent vitamin A accumulation in hepatocytes rather than HSC in HFC-fed mice. Palmitic acid exposure increased Lrat mRNA levels in primary rat hepatocytes and promoted retinyl palmitate accumulation when co-treated with retinol, which was not detected for similarly-treated primary rat HSCs. CONCLUSION: NAFLD leads to cell type-specific rearrangements in retinol metabolism leading to vitamin A accumulation in hepatocytes. This may promote disease progression and/or affect therapeutic approaches targeting nuclear receptors

The neutron and its role in cosmology and particle physics

Experiments with cold and ultracold neutrons have reached a level of precision such that problems far beyond the scale of the present Standard Model of particle physics become accessible to experimental investigation. Due to the close links between particle physics and cosmology, these studies also permit a deep look into the very first instances of our universe. First addressed in this article, both in theory and experiment, is the problem of baryogenesis ... The question how baryogenesis could have happened is open to experimental tests, and it turns out that this problem can be curbed by the very stringent limits on an electric dipole moment of the neutron, a quantity that also has deep implications for particle physics. Then we discuss the recent spectacular observation of neutron quantization in the earth's gravitational field and of resonance transitions between such gravitational energy states. These measurements, together with new evaluations of neutron scattering data, set new constraints on deviations from Newton's gravitational law at the picometer scale. Such deviations are predicted in modern theories with extra-dimensions that propose unification of the Planck scale with the scale of the Standard Model ... Another main topic is the weak-interaction parameters in various fields of physics and astrophysics that must all be derived from measured neutron decay data. Up to now, about 10 different neutron decay observables have been measured, much more than needed in the electroweak Standard Model. This allows various precise tests for new physics beyond the Standard Model, competing with or surpassing similar tests at high-energy. The review ends with a discussion of neutron and nuclear data required in the synthesis of the elements during the "first three minutes" and later on in stellar nucleosynthesis.Comment: 91 pages, 30 figures, accepted by Reviews of Modern Physic

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Le muséum sur roues : un engagement auprès et pour les publics

Offre originale pour un muséum, les espaces mobiles développés par le Musée national d’Histoire naturelle du Luxembourg permettent d’assurer la mission de médiation scientifique sur l’entièreté du territoire, y compris dans les zones rurales ou éloignées. Une opportunité de toucher et de conquérir un nouveau public

Calibration of partial safety factors for fatigue design of steel bridges

The aim of this paper is to propose a new framework for assessment of fatigue partial safety factors with focus on steel bridges welded joints. Fatigue resistance S-N curves for constant amplitude (CA) and variable amplitude (VA) loadings are defined using a novel probabilistic approach based on Maximum Likelihood (ML) and Monte-Carlo Simulations (MCS) methods. The proposed framework includes ML-MCS-based S-N curves of different welded detail categories and it is applicable for the case of deterministic and probabilistic CA loadings as well as for VA loadings. One example is developed, that of a typical bridge fatigue sensitive welded joint. The results are compared to Eurocode standards both in terms of partial safety factor values and of characteristic S-N curves.Non UBCUnreviewedThis collection contains the proceedings of ICASP12, the 12th International Conference on Applications of Statistics and Probability in Civil Engineering held in Vancouver, Canada on July 12-15, 2015. Abstracts were peer-reviewed and authors of accepted abstracts were invited to submit full papers. Also full papers were peer reviewed. The editor for this collection is Professor Terje Haukaas, Department of Civil Engineering, UBC Vancouver.FacultyOthe

Sedimentological and geochemical facies changes in the NE Paris Basin linked to the end-Triassic mass extinction event

editorial reviewe

novembre-décembre 2020

Les professionnels mobilisés L’engagement des professionnels peut-il être un élément définissant le musée ? Voici quelques années, en 2017, dans le cadre du colloque de l’Icofom Définir le musée du XXIe siècle, Jesus Pedro Lorente a posé cette question. Partant du constat que la définition du musée par l’Icom ne faisait aucune référence au besoin d’un technicien et que certaines tendances de la nouvelle muséologie revendiquaient des musées autogérés, le professeur de l’université de Saragosse s’est interrogé sur la place et le rôle des professionnels de musées. Cette question reste particulièrement prégnante. Après plusieurs semaines, qui ont correspondu pour les professionnels des musées à une phase de réouverture de leurs lieux aux publics, de nouvelles mesures liées à l’évolution de la crise sanitaire impactent aujourd’hui à nouveau leur fonctionnement. Marquée par une crise économique sans précédent, cette période induit des changements : certaines structures font preuve de résilience et se réinventent. La hiérarchie des savoirs, entre professionnels et publics, est questionnée. La richesse de ce numéro de la lettre se caractérise par la diversité des retours d’expériences proposés. Ceux-ci abordent autant des questions liées à la conservation préventive, que des sujets liés à l’exposition, à l’expérience de visite ou aux outils pour faire sortir le muséum du Luxembourg de ses murs. L’évocation du projet du Centre culturel du Vanuatu est aussi un bel exemple de valorisation et de transmission de l’héritage culturel d’un archipel. D’une dimension patrimoniale à des actions de médiation, un bel équilibre se dessine entre les différents textes proposés. À leur manière, ils répondent à la question de Jesus Pedro Lorente. Si le musée se définit par ses missions, ses collections, ses publics ou son rôle dans et pour la société, il existe grâces aux différents corps de métiers qui le font vivre. Projet singulier, centre de ressources à destination des professionnels de la sphère muséale, c’est aussi une idée que défend l’Ocim. Samuel Cordier, directeur de l'Oci