Magnetic activity, differential rotation and dynamo action in the pulsating F9IV star KIC 5955122

We present photometric spot modeling of the nearly four-year long light-curve of the Kepler target KIC 5955122 in terms of persisting dark circular surface features. With a Bayesian technique, we produced a plausible surface map that shows dozens of small spots. After some artifacts are removed, the residuals are at $\pm 0.16$\,mmag. The shortest rotational period found is $P = 16.4 \pm 0.2$ days. The equator-to-pole extrapolated differential rotation is $0.25 \pm 0.02$ rad/d. The spots are roughly half as bright as the unperturbed stellar photosphere. Spot latitudes are restricted to the zone $\pm 60^\circ$ latitude. There is no indication for any near-pole spots. In addition, the p-mode pulsations enabled us to determine the evolutionary status of the star, the extension of the convective zone, and its radius and mass. We discuss the possibility that the clear signature of active regions in the light curve of the F9IV star KIC 5955122 is produced by a flux-transport dynamo action at the base of the convection zone. In particular, we argue that this star has evolved from an active to a quiet status during the Q0--Q16 period of observation, and we predict, according to our dynamo model, that the characteristic activity cycle is of the order of the solar one.Comment: 9 pages, 12 figures, to be published on A&

The local order of supercooled water in solution with LiCl studied by NMR proton chemical shift

We study by means of Nuclear Magnetic Resonance (NMR) spectroscopy the local order of water molecules in solution with lithium chloride at eutectic concentration. In particular, by measuring the proton chemical shift as a function of the temperature in the interval 203K < T < 320K, we observe a net change at about 235 K. We ascribe this result to the increase of the hydrogen bond interaction that on decreasing the temperature favors the formation of the network that characterizes the low density liquid phase of water. Furthermore, the Gaussian deconvolution of the NMR peak allows the investigation of the mutual difference between the chemical shift of water solvating lithium and chlorine individually. The thermal behavior of this quantity confirms previous results about the role of the temperature in the solvation mechanisms down to about 225 K. This temperature coincides with that of the so-called Widom line for water supporting the liquid-liquid transition hypothesis

SAT0460 INGESTION OF LEMON JUICE MAY MODULATE BONE METABOLISM.

Background:An association between bone health and consumption of citrus fruits have been previously reported; however, the effect of lemon juice on bone metabolism have not been explored yet.Objectives:To investigate bone metabolic changes in postmenopausal women assuming lemon juice.Methods:Participants were postmenopausal osteoporotic women without history of clinical fractures who agreed to enrich their diet with lemon juice (Acti Lemon, Polenghi) over a 2-month period. The daily juice dose of 30 ml we suggested was equivalent to one Sicilian organic lemon. Surrogate markers of bone formation as procollagen type 1 N-propeptide (P1NP) and of bone resorption as C-terminal telopeptide of type I collagen (CTX), but also some regulators of bone metabolism as RANK-L, OPG, RANK-L/OPG ratio and sclerostin were assessed at baseline and then at 1 and 2 months after lemon juice administration. Controls were represented by a placebo group of age-matched osteoporotic postmenopausal women.Results:47 participants [mean age 60.2 ± 4.1 yr.] completed the study, without reporting any adverse events. Lemon juice was well tolerated. Over the observation period modifications of bone metabolism occurred: we detected a decreased RANK-L/OPG ratio and increased CTX levels at all time points vs. baseline. Particularly, change at month-1 of sclerostin (versus baseline) has been positively associated with change at month-1 and month-2 of CTX (r=0.46, p=0.01 and r=0.43, p=0.01, respectively). Change at month-1 of OPG was positively associated with change at month-1 of P1NP (r=0.49, p=0.006). Change at month-1 of RANKL/OPG has been related with variation at day 30 of P1NP (r=-0.44, p=0.013). Variation of P1NP at month-1 was related with sclerostin variation at day 30 (r=-0.56, p=0.02) and month-2 vs. baseline value (r=0.44, p=0.017) and with sclerostin variation between month-1 and month-2 (r=0.69, p<0.001). Variation of P1NP between month-1 and month-2 was associated with RANKL change at month-1 (r=-0.35, p=0.05), with sclerostin change at month-1 (r=-0.49, p=0.008) and with sclerostin change between month-1 and month-2 (r=0.41, p=0.028). At a multiple regression analysis the change of P1NP between month-1 and month-2 was independently predicted by the change of sclerostin at month-1 (ß=-1.5, SE 0.5, p=0.006), after correcting for age, BMI and change of RANKL and CTX levels at month-1. No significant modifications raised from controls.Conclusion:Drinking lemon juice may boost bone metabolic changes involving both bone resorption and bone formation.Disclosure of Interests:None declare

MicroRNA as Possible Mediators of the Synergistic Effect of Celecoxib and Glucosamine Sulfate in Human Osteoarthritic Chondrocyte Exposed to IL-1β

This study investigated the role of a pattern of microRNA (miRNA) as possible mediators of celecoxib and prescription-grade glucosamine sulfate (GS) effects in human osteoarthritis (OA) chondrocytes. Chondrocytes were treated with celecoxib (1.85 µM) and GS (9 µM), alone or in combination, for 24 h, with or without interleukin (IL)-1β (10 ng/mL). Cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, apoptosis and reactive oxygen species (ROS) by cytometry, nitric oxide (NO) by Griess method. Gene levels of miRNA, antioxidant enzymes, nuclear factor erythroid (NRF)2, and B-cell lymphoma (BCL)2 expressions were analyzed by quantitative real time polymerase chain reaction (real time PCR). Protein expression of NRF2 and BCL2 was also detected at immunofluorescence and western blot. Celecoxib and GS, alone or in combination, significantly increased viability, reduced apoptosis, ROS and NO production and the gene expression of miR-34a, -146a, -181a, -210, in comparison to baseline and to IL-1β. The transfection with miRNA specific inhibitors significantly counteracted the IL-1β activity and potentiated the properties of celecoxib and GS on viability, apoptosis and oxidant system, through nuclear factor (NF)-κB regulation. The observed effects were enhanced when the drugs were tested in combination. Our data confirmed the synergistic anti-inflammatory and chondroprotective properties of celecoxib and GS, suggesting microRNA as possible mediators

MicroRNA as Possible Mediators of the Synergistic Effect of Celecoxib and Glucosamine Sulfate in Human Osteoarthritic Chondrocyte Exposed to IL-1β

This study investigated the role of a pattern of microRNA (miRNA) as possible mediators of celecoxib and prescription-grade glucosamine sulfate (GS) effects in human osteoarthritis (OA) chondrocytes. Chondrocytes were treated with celecoxib (1.85 µM) and GS (9 µM), alone or in combination, for 24 h, with or without interleukin (IL)-1β (10 ng/mL). Cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, apoptosis and reactive oxygen species (ROS) by cytometry, nitric oxide (NO) by Griess method. Gene levels of miRNA, antioxidant enzymes, nuclear factor erythroid (NRF)2, and B-cell lymphoma (BCL)2 expressions were analyzed by quantitative real time polymerase chain reaction (real time PCR). Protein expression of NRF2 and BCL2 was also detected at immunofluorescence and western blot. Celecoxib and GS, alone or in combination, significantly increased viability, reduced apoptosis, ROS and NO production and the gene expression of miR-34a, -146a, -181a, -210, in comparison to baseline and to IL-1β. The transfection with miRNA specific inhibitors significantly counteracted the IL-1β activity and potentiated the properties of celecoxib and GS on viability, apoptosis and oxidant system, through nuclear factor (NF)-κB regulation. The observed effects were enhanced when the drugs were tested in combination. Our data confirmed the synergistic anti-inflammatory and chondroprotective properties of celecoxib and GS, suggesting microRNA as possible mediators

Micrometeoroid and Lunar Secondary Ejecta Flux Measurements: Comparison of Three Acoustic Systems

This report examines the inherent capability of three large-area acoustic sensor systems and their applicability for micrometeoroids (MM) and lunar secondary ejecta (SE) detection and characterization for future lunar exploration activities. Discussion is limited to instruments that can be fabricated and deployed with low resource requirements. Previously deployed impact detection probes typically have instrumented capture areas less than 0.2 square meters. Since the particle flux decreases rapidly with increased particle size, such small-area sensors rarely encounter particles in the size range above 50 microns, and even their sampling the population above 10 microns is typically limited. Characterizing the sparse dust population in the size range above 50 microns requires a very large-area capture instrument. However it is also important that such an instrument simultaneously measures the population of the smaller particles, so as to provide a complete instantaneous snapshot of the population. For lunar or planetary surface studies, the system constraints are significant. The instrument must be as large as possible to sample the population of the largest MM. This is needed to reliably assess the particle impact risks and to develop cost-effective shielding designs for habitats, astronauts, and critical instrument. The instrument should also have very high sensitivity to measure the flux of small and slow SE particles. is the SE environment is currently poorly characterized, and possess a contamination risk to machinery and personnel involved in exploration. Deployment also requires that the instrument add very little additional mass to the spacecraft. Three acoustic systems are being explored for this application

High temperature stability of Terphenyl based thermal oils

Thermal oils are nowadays widely used as heat transfer fluids or cooling media in industrial and energy production plants. Currently, very few data are available about their thermal stability in function of the operating temperatures, which is a crucial parameter to estimate oil structural changes and their possible effects the maximum fluids lifetime. The present work is concerned with ageing tests on a commercially used thermal oil at temperatures higher than the nominal working ones, including a full post-test characterization. At this aim, a dedicated experimental set-up was designed and constructed to study the degradation kinetics, and to qualitatively and quantitatively analyze the released gases. As a result, the kinetic parameters were estimated, along with the related changes in the oil thermos-physical properties

Limits on surface gravities of Kepler planet-candidate host stars from non-detection of solar-like oscillations

We present a novel method for estimating lower-limit surface gravities log g of Kepler targets whose data do not allow the detection of solar-like oscillations. The method is tested using an ensemble of solar-type stars observed in the context of the Kepler Asteroseismic Science Consortium. We then proceed to estimate lower-limit log g for a cohort of Kepler solar-type planet-candidate host stars with no detected oscillations. Limits on fundamental stellar properties, as provided by this work, are likely to be useful in the characterization of the corresponding candidate planetary systems. Furthermore, an important byproduct of the current work is the confirmation that amplitudes of solar-like oscillations are suppressed in stars with increased levels of surface magnetic activity.Comment: Accepted for publication in ApJ; 35 pages, 10 figures, 5 table

'The terrible twos': Gaining control in the nursery?

'The terrible twos' are often described as a time of 'gaining control', usually thought of as adults asserting control over children, who learn to control themselves. However, toddlerhood is as much about children learning to take control for themselves. This paper is an attempt to detail something of the social geography in the toddler room of a Scottish nursery, considering both styles of adult control and the ways in which toddlers attempt to appropriate and reconfigure space and time for themselves. That is, the ways in which space and time are negotiated in the course of day-to-day nursery life