Sources of Bias in Synchronization Measures and how to Minimize Their Effects on the Estimation of Synchronicity: Application to the Uterine Electromyogram

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Impaired Control of Body Cooling during Heterothermia Represents the Major Energetic Constraint in an Aging Non-Human Primate Exposed to Cold

Daily heterothermia is used by small mammals for energy and water savings, and seems to be preferentially exhibited during winter rather than during summer. This feature induces a trade-off between the energy saved during daily heterothermia and the energy cost of arousal, which can impact energy balance and survival under harsh environmental conditions. Especially, aging may significantly affect such trade off during cold-induced energy stress, but direct evidences are still lacking. We hypothesized that aging could alter the energetics of daily heterothermia, and that the effects could differ according to season. In the gray mouse lemur (Microcebus murinus), a non-human primate species which exhibits daily heterothermia, we investigated the effects of exposures to 25 and 12°C on body composition, energy balance, patterns of heterothermia and water turnover in adult (N = 8) and aged animals (N = 7) acclimated to winter-like or summer-like photoperiods

The Torpid State:Recent Advances in Metabolic Adaptations and Protective Mechanisms(dagger)

Torpor and hibernation are powerful strategies enabling animals to survive periods of low resource availability. The state of torpor results from an active and drastic reduction of an individual's metabolic rate (MR) associated with a relatively pronounced decrease in body temperature. To date, several forms of torpor have been described in all three mammalian subclasses, i.e., monotremes, marsupials, and placentals, as well as in a few avian orders. This review highlights some of the characteristics, from the whole organism down to cellular and molecular aspects, associated with the torpor phenotype. The first part of this review focuses on the specific metabolic adaptations of torpor, as it is used by many species from temperate zones. This notably includes the endocrine changes involved in fat- and food-storing hibernating species, explaining biomedical implications of MR depression. We further compare adaptive mechanisms occurring in opportunistic vs. seasonal heterotherms, such as tropical and sub-tropical species. Such comparisons bring new insights into the metabolic origins of hibernation among tropical species, including resistance mechanisms to oxidative stress. The second section of this review emphasizes the mechanisms enabling heterotherms to protect their key organs against potential threats, such as reactive oxygen species, associated with the torpid state. We notably address the mechanisms of cellular rehabilitation and protection during torpor and hibernation, with an emphasis on the brain, a central organ requiring protection during torpor and recovery. Also, a special focus is given to the role of an ubiquitous and readily-diffusing molecule, hydrogen sulfide (H2S), in protecting against ischemia-reperfusion damage in various organs over the torpor-arousal cycle and during the torpid state. We conclude that (i) the flexibility of torpor use as an adaptive strategy enables different heterothermic species to substantially suppress their energy needs during periods of severely reduced food availability, (ii) the torpor phenotype implies marked metabolic adaptations from the whole organism down to cellular and molecular levels, and (iii) the torpid state is associated with highly efficient rehabilitation and protective mechanisms ensuring the continuity of proper bodily functions. Comparison of mechanisms in monotremes and marsupials is warranted for understanding the origin and evolution of mammalian torpor

The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society

Etude des répercussions de la position du placenta sur les caractéristiques des contractions utérines

L'électrohystérogramme (EHG) représente l'activité électrique générée par l'utérus pendant les contractions (CT). L'EHG est composé principalement de deux composantes spectrales distinctes, FWL et FWH. Un algorithme d'analyse des CT a été développé pour détecter une éventuelle menace d'accouchement prématuré. Cependant, les performances du diagnostic se sont avérées inférieures chez des femmes présentant un placenta antérieur. Nous avons donc émis l'hypothèse que le placenta exercerait une influence locale sur les caractéristiques des CT. Nous avons mis en place deux protocoles expérimentaux adaptés à l'enregistrement des CT placentaire (P) et non placentaire (NP), chez le macaque et chez la femme. Les CT ont été analysées, dans chacune des situations par leurs spectres d'énergie et de puissance. Nous avons aussi développé une méthode robuste d'extraction des ridges des représentations temps/fréquence. La méthode GVF-Snake nous a permis de caractériser FWL et FWH. Nous avons montré que le placenta modifie les caractéristiques de l'EHG. Nous avons aussi observé que l'évolution des caractéristiques des CT est identique quelle que soit la position placentaire. Les différences entre les CT NP et P tendent à disparaître avec l'avancée du terme. Par contre, chez la femme, nous avons clairement mis en évidence un effet de la position des électrodes sur les caractéristiques des CT. Nous avons montré que cet effet est dû à la distance entre la source des potentiels et les électrodes, et à l'épaisseur de tissus inactifs entre les électrodes et le muscle sous-jacent. Enfin, nous avons remarqué que les CT présentent un rythme circadien pour plusieurs paramètres de FWL et FWH.The electrohysterogram (EHG) is the electrical activity generated by the uterus during contractions (CT). The EHG is mainly composed of two distinct frequency components, called FWL and FWL. An algorithm was developed for the detection of a possible preterm delivery risk in women. However, the diagnosis performances are lower for women with an anterior placenta during the recording. Thus, we made the hypothesis that the placenta exerts a local influence on the characteristics of CT. We have developed two experimental protocols specially suited for the recording of placental (P) CT and non placental (NP) contractions, in monkey and women. AlI CT have been analyzed by their energy and power spectrum. Moreover, we have developed a powerful method for the extraction of the time-frequency ridges. The GVF-Snake method permitted us to characterized both FWL and FWH. We proved that the placenta modifies the characteristics of the EHG. We also showed that the CT characteristics evolution is similar whatever the placental position. Differences between NP and P CT tend also to disappear with the advance of gestation. Nevertheless, we pointed out an effect of the electrodes position on the characteristics of CT. This effect is due to the distance between electrodes and the source of potentials, and also to the thickness between electrodes and the surrounding muscle. Moreover, we clearly evidenced circadian rhythms for several characteristics of FWL and FWH.COMPIEGNE-BU (601592101) / SudocSudocFranceF

Daily rhythms of core temperature and locomotor activity indicate different adaptive strategies to cold exposure in adult and aged mouse lemurs acclimated to a summer-like photoperiod.

International audienceDaily variations in core temperature (Tc) within the normothermic range imply thermoregulatory processes that are essential for optimal function and survival. Higher susceptibility towards cold exposure in older animals suggests that these processes are disturbed with age. In the mouse lemur, a long-day breeder, we tested whether aging affected circadian rhythmicity of Tc, locomotor activity (LA), and energy balance under long-day conditions when exposed to cold. Adult (N = 7) and aged (N = 5) mouse lemurs acclimated to LD14/10 were exposed to 10-day periods at 25 and 12 degrees C. Tc and LA rhythms were recorded by telemetry, and caloric intake (CI), body mass changes, and plasma IGF-1 were measured. During exposure to 25 degrees C, both adult and aged mouse lemurs exhibited strong daily variations in Tc. Aged animals exhibited lower levels of nocturnal LA and nocturnal and diurnal Tc levels in comparison to adults. Body mass and IGF-1 levels remained unchanged with aging. Under cold exposure, torpor bout occurrence was never observed whatever the age category. Adult and aged mouse lemurs maintained their Tc in the normothermic range and a positive energy balance. All animals exhibited increase in CI and decrease in IGF-1 in response to cold. The decrease in IGF-1 was delayed in aged mouse lemurs compared to adults. Moreover, both adult and aged animals responded to cold exposure by increasing their diurnal LA compared to those under Ta = 25 degrees C. However, aged animals exhibited a strong decrease in nocturnal LA and Tc, whereas cold effects were only slight in adults. The temporal organization and amplitude of the daily phase of low Tc were particularly well preserved under cold exposure in both age groups. Sexually active mouse lemurs exposed to cold thus seemed to prevent torpor exhibition and temporal disorganization of daily rhythms of Tc, even during aging. However, although energy balance was not impaired with age in mouse lemurs after cold exposure, aging was associated with lower LA and Tc during the night and delayed decrease in IGF-1. This might reflect that adaptive strategies to cold exposure differ with age in mouse lemurs acclimated to a summer-like photoperiod

Temporal Control of Metabolic Amplitude by Nocturnin

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Sex-Specific Response to Caloric Restriction After Reproductive Investment in Microcebus murinus: An Integrative Approach

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