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The prevalence of sleep problems among pregnant women is over 50%, and daytime sleepiness is among the most common sleep problems. Previous studies have associated antenatal sleep problems with adverse maternal health and neonatal outcomes, but the consequences of antenatal sleep problems and particularly daytime sleepiness on child psychological development have not been assessed prospectively.
In this prospective cohort study including 111 mother-child dyads, we examined the associations of maternal daytime sleepiness during pregnancy, assessed at 17 and 28 weeks of gestation using the Epworth Sleepiness Scale, with child neuropsychiatric problems and neuropsychological development, assessed with mother-rated questionnaires and individually administered neuropsychological tests, at child age 2.6–5.7 years (mean = 4.3 years).
Independently of sociodemographic and perinatal covariates and maternal depressive and anxiety symptoms during and/or after pregnancy, maternal antenatal daytime sleepiness was associated with increased total [unstandardized regression coefficient (B) = 0.25 standard deviation (s.d.) units; 95% confidence interval (CI) 0.01–0.48] and internalizing (B = 0.25 s.d.s: 95% CI 0.01–0.49) psychiatric problems and ADHD symptoms (B = 0.27 s.d.s: 95% CI 0.04–0.50) in children, and with poorer executive function, particularly in the areas of attention, working memory and inhibitory control (B = −0.39 s.d.s: 95% CI −0.69 to −0.10).
Maternal antenatal daytime sleepiness carries adverse consequences for offspring psychological development. The assessment of sleep problems may be an important addition to standard antenatal care.
Insomnia and depression are highly comorbid and mutually exacerbate clinical trajectories and outcomes. Cognitive behavioral therapy for insomnia (CBT-I) effectively reduces both insomnia and depression severity, and can be delivered digitally. This could substantially increase the accessibility to CBT-I, which could reduce the health disparities related to insomnia; however, the efficacy of digital CBT-I (dCBT-I) across a range of demographic groups has not yet been adequately examined. This randomized placebo-controlled trial examined the efficacy of dCBT-I in reducing both insomnia and depression across a wide range of demographic groups.
Of 1358 individuals with insomnia randomized, a final sample of 358 were retained in the dCBT-I condition and 300 in the online sleep education condition. Severity of insomnia and depression was examined as a dependent variable. Race, socioeconomic status (SES; household income and education), gender, and age were also tested as independent moderators of treatment effects.
The dCBT-I condition yielded greater reductions in both insomnia and depression severity than sleep education, with significantly higher rates of remission following treatment. Demographic variables (i.e. income, race, sex, age, education) were not significant moderators of the treatment effects, suggesting that dCBT-I is comparably efficacious across a wide range of demographic groups. Furthermore, while differences in attrition were found based on SES, attrition did not differ between white and black participants.
Results provide evidence that the wide dissemination of dCBT-I may effectively target both insomnia and comorbid depression across a wide spectrum of the population.
“Deep learning” is finding more and more applications everywhere, and astronomy is not an exception. This talk described the application of convolutional neural networks to time-domain astronomy, specifically to light-curves of sources. The work that is discussed is based on a published paper to which reference can be made for more detail. The talk finished with a note cautioning new practitioners about the pitfalls lurking in out-of-the-box use of deep-learning techniques.
The element boron belongs, together with lithium and beryllium, to a known trio of important elements for the study of evolutionary processes in low mass stars. Because B is the least fragile of this trio to be destroyed in the stellar interiors, it can be used to test if the Li enrichment is of planetary origin. Here, for the first time, boron lines are examined in the UV for four giants with different degrees of large Li enrichment by means of observations with the Hubble telescope. Two main results are found in our study. One is that to first approximation B abundances appear not to be in excess, invalidating the planet engulfment mechanism. The second one is that the two stars with very large Li abundances present emission lines indicating that quite strong active chromospheres are acting in these very Li-rich giants. These new results obtained from the UV complement our recent studies in the mid-IR (de la Reza et al. 2015) where strong emission-line features of organic material were found in the spectra of some Li-rich stars.
Prenatal maternal obesity has been linked to adverse childhood neuropsychiatric outcomes, including increased symptoms of attention deficit hyperactivity disorder (ADHD), internalizing and externalizing problems, affective disorders and neurodevelopmental problems but few studies have studied neuropsychiatric outcomes among offspring born to very severely obese women or assessed potential familial confounding by maternal psychological distress.
We evaluated neuropsychiatric symptoms in 112 children aged 3–5 years whose mothers had participated in a longitudinal study of obesity in pregnancy (50 very severe obesity, BMI ⩾40 kg/m2, obese class III and 62 lean, BMI 18.5–25 kg/m2). The mothers completed the Conners’ Hyperactivity Scale, Early Symptomatic Syndrome Eliciting Neurodevelopmental Clinical Examination Questionnaire (ESSENCE-Q), Child's Sleep Habits Questionnaire (CSHQ), Strengths and Difficulties Questionnaire (SDQ), and Child Behavior Checklist (CBCL) to assess child neuropsychiatric symptoms. Covariates included child's sex, age, birthweight, gestational age, socioeconomic deprivation levels, maternal age, parity, smoking status during pregnancy, gestational diabetes and maternal concurrent symptoms of anxiety and depression assessed using State Anxiety of Spielberger State-Trait Anxiety Index (STAI) and General Health Questionnaire (GHQ), respectively.
Children exposed to prenatal maternal very severe obesity had significantly higher scores in the Conners’ Hyperactivity Scale; ESSENCE-Q; total sleep problems in CSHQ; hyperactivity, conduct problems and total difficulties scales of the SDQ; higher externalizing and total problems, anxious/depressed, aggressive behaviour and other problem syndrome scores and higher DSM-oriented affective, anxiety and ADHD problems in CBCL. Prenatal maternal very severe obesity remained a significant predictor of child neuropsychiatric problems across multiple scales independent of demographic factors, prenatal factors and maternal concurrent symptoms of anxiety and depression.
Prenatal maternal very severe obesity is a strong predictor of increased neuropsychiatric problems in early childhood.
Previous studies have suggested that a high intake of sugar-sweetened beverages is positively associated with the risk of a coronary event. However, a few studies have examined the association between sucrose (the most common extrinsic sugar in Sweden) and incident coronary events. The objective of the present study was to examine the associations between sucrose intake and coronary event risk and to determine whether these associations are specific to certain subgroups of the population (i.e. according to physical activity, obesity status, educational level, alcohol consumption, smoking habits, intake of fat and intake of fruits and vegetables). We performed a prospective analysis on 26 190 individuals (62 % women) free from diabetes and without a history of CVD from the Swedish population-based Malmö Diet and Cancer cohort. Over an average of 17 years of follow-up (457 131 person-years), 2493 incident cases of coronary events were identified. Sucrose intake was obtained from an interview-based diet history method, including 7-d records of prepared meals and cold beverages and a 168-item diet questionnaire covering other foods. Participants who consumed >15 % of their energy intake (E%) from sucrose showed a 37 (95 % CI 13, 66) % increased risk of a coronary event compared with the lowest sucrose consumers (<5 E%) after adjusting for potential confounders. The association was not modified by the selected lifestyle factors. The results indicated that sucrose consumption higher than 15 E% (5 % of this population) is associated with an increased risk of a coronary event.
We present preliminary results of grating observations of YY Mensae and V824 Arae by Chandra and XMM-Newton. Spectral features are presented in the context of the emission measure distributions, the coronal abundances, and plasma electron densities. In particular, we observe a coronal N/C enhancement in YY Men believed to reflect the photospheric composition (CN cycle). Finally, we interpret line broadening in YY Men as Doppler thermal broadening in its very hot corona.
We present new X-ray, EUV, and radio observations of the coronal emission from the RS CVn binaries HR1099 (V711 Tau) and σ2 CrB. RS CVn systems possess coronae that display extreme activity levels and frequent flaring. Our observations provide multiwavelength records of coronal variability and flaring over more than two binary orbits for each system. While the EUV and X-ray spectra show the flare response of the thermal plasma, the radio data give the corresponding information for the nonthermal electron population. The HR1099 data contain one of the most energetic flare outbursts observed from HR1099 that lasts for over 3 days. Coronal flaring is common in these systems and, in fact, is the normal condition.
The MACHO data base has been used to examine light curves of all red giant stars brighter than Mbol ∼ −2 in a 0.5° × 0.5° area of the LMC bar. Periods, often multiple, have been searched for in all stars found to be variable. Five distinct period-luminosity sequences have been found on the low mass (M ≲ 2.25M⊙) giant branch. Comparison of observed periods, luminosities and period ratios with theoretical models identifies Miras unambiguously as radial fundamental mode pulsators, while semi-regular variables can be pulsating in the 1st, 2nd or 3rd overtone, or even the fundamental. All these variables lie on just 3 of the 5 distinct sequences, and they all appear to be on the AGB.
The fourth sequence contains red giants on the first giant branch (FGB) or at the red end of the core-helium burning loops of intermediate mass stars (M ≳ 2.25M⊙). The light curves of these stars strongly suggest that they are contact binaries, and they make up ∼0.5% of stars within 1 mag. of the FGB tip. Stars on the fifth sequence show semi-regular, eclipse-like light curves. The light curves and periods of these stars suggest that they are in semi-detached binaries, transfering mass to an invisible companion via a stellar wind or Roche lobe overflow. They make up ∼25% of AGB stars. If the existence of these red giant contact and semi-detached binaries is confirmed, then extant theories of binary star evolution will require substantial modification.
Professor Colomb resigned as President of the Commission because of pressing demands of work. The Organizing Committee appointed Stuart Bowyer (Vice President) as Acting President.
The Commission has proposed changing its name to “Bioastronomy: Search for Extrasolar Planets and Extraterrestial Life” to reflect our long-standing involvement in the search for extrasolar planets. The name change is pending approval of the IAU.
We present the preliminary results of a frequency analysis of 1457 fundamental mode RR Lyrae (RR0) stars in the Large Magellanic Cloud (LMC) from MACHO Project photometry. We find the same classes of pulsational behavior as were found in our earlier survey of first overtone RR Lyrae (RR1) stars. Variables whose prewhitened power spectra contain one or two peaks close to the main frequency component in the original power spectra are commonly known as Blazhko-type variables. The present analysis shows the overall frequency of Blazhko-type stars in the total RR0 population analysed to date to be ≈ 10%. This is lower than the often cited Galactic field/globular rate of 20-30% (Szeidl, 1988).
The incidence rate of Blazhko-type variability in the LMC appears to be about three times higher in RR0 stars than in RR1 stars. This puts important constraints on possible models of the Blazhko effect.
We present the first massive frequency analysis of the 1200 first overtone RR Lyrae stars in the Large Magellanic Cloud observed in the first 4.3 yr of the MACHO project. Besides the many new double-mode variables, we also discovered stars with closely spaced frequencies. These variables are most probably nonradial pulsators.
We present the current status of the spectroscopic follow-up of a large number of RR Lyrae (RRL) halo overdensity candidates recently found by Torrealba et al. (2015) using southern-hemisphere data from the Catalina Real-time Transient Survey (CRTS). Characterizing the individual RRL stars in these overdensities is crucial to confirm them as real halo substructures. Low-resolution spectra have been obtained for RRL stars in 11 different overdensities, using the SOAR and Magellan telescopes. Radial velocities and metallicities have been derived so far for 123 and 99 RRL stars, respectively.
The Fezzan Project completed its five-year fieldwork cycle in 2001. The geographical research team located numerous additional palaeolake sites within the Edeyen Ubari, using a combination of Remote Sensing technology and field visits. Additional samples were taken for analysis and dating from many lake edge locations, relating to both the large Pleistocene lake and to the numerous smaller Holocene lakes that have been identified by the team. The excavations at Old Germa were taken down through Garamantian occupation levels to the natural subsoil below the earliest cultural horizon. The earliest activity, represented by a few mudbrick walls and hearths built directly on the natural soil, is believed to date to c. 400-300 BC. Traces of several phases of Garamantian buildings were uncovered, along with numerous rubbish pits, which yielded a rich assemblage of finds, including, for the first time, examples of Garamantian figurines, small 3-D sculptures of humans and animals. Work on the various classes of finds (pottery, small finds, lithics and other stone artefacts, metallurgical evidence, etc.) complemented the excavation work. In addition, a small amount of further survey work was carried out on sites in the Wadi al-Ajal, along with a contour survey of Old Germa and standing building survey at a number of other sites.
We present the results of a numerical simulation of the corona and wind structure of the Sun-like exoplanet-host GJ 3021 using a global magnetohydrodynamic (MHD) model. The simulation is driven by the radial component of the surface magnetic field recovered with the Zeeman Doppler Imaging (ZDI) technique. We consider two different ZDI input maps, which have similar large-scale structures but different spatial resolutions and field strengths. These maps arise from different but comparable models used to fit the observed circularly polarised spectra of the star. Our simulations show that the structure of the inner corona is consistent among the considered cases. Larger discrepancies are found in the wind structure, in particular in the radial wind speed and the Alfvén surface topology. These elements can have a significant impact on the mass loss and angular momentum loss predicted for this system and in other studies based on this numerical data-driven approach.
The characteristics of unbounded flow past an impulsively started planar energy extracting device, such as a wind or tidal turbine, are studied theoretically, numerically and experimentally. The initial thrust on an impulsively started device, which can be more than double the steady thrust, is an important consideration for design and safe operation. The energy sink is modelled here as an ‘actuator surface’ which imposes a uniform pressure discontinuity in the fluid proportional to the square of the fluid speed normal to the surface, the fluid density, and a dimensionless resistance coefficient. The flow past the actuator is studied theoretically for the case of weak resistance using an unsteady model which recovers steady linear momentum theory in the limit of long time. For the case of strong resistance the flow is studied numerically using the point vortex method. Experimental measurements of thrust on a mesh towed through static water are compared to the numerical results and show good agreement. The thrust on an impulsively started device is estimated, for a typical installation, to fall to within 10 % of the steady value within ∼1 min. The numerical model is also used to simulate the gradual startup of a device, yielding estimates of the time constant necessary in a control system in order to reduce peak thrusts in practice.
X-ray specular and off-specular reflectivity studies have been carried out to study the density modulations in liquids confined between two smooth silicon mirrors. The special technique as well as the advantages of using high energy and high brilliance synchrotron x-ray beams for carrying out such experiments will be discussed. Results will be presented on the ordering of octamethyl-cyclotetrasiloxane (OMCTS) as a function of the confining pressure, where we find evidence of layering as the gap is decreased from macroscopic down to a few nanometers.
The use of spontaneous rotational and vibrational Raman scattering for nonperturbing measurements of temperature and gas phase concentrations in combustion and in materials processing is reviewed. Theory of Raman intensities is briefly discussed and examples of Raman scattering from metal halide vapors in high temperature furnaces, laminar flames, and turbulent flames are given to demonstrate its capabilities and limitations. At present spontaneous Raman scattering is the only method which can provide simultaneous nonperturbing measurements of temperature and many species concentrations with high spatial (≤ 0.1 mm3) and temporal (≤ 1μs) resolution. Rotational Raman scattering is generally preferred for low temperature measurements (≤ 1200 K), and vibrational Raman scattering is better for measurements of higher temperatures and of multiple-species concentrations. The disadvantages of Raman scattering stem for the weakness of the nonresonant Raman interaction which limits its sensitivity to major species concentrations, renders it vulnerable to interferences from other sources of visible radiation, and requires high powered lasers and sensitive detectors. Data from Raman scattering measurements, particularly when coupled with data from other laser diagnostic techniques and when compared to computer model calculations, have led to a better understanding of the complex interactions between fluid mechanics and chemical reactions which can govern the operation of turbulent combustors or chemical flow reactors.
Direct measurements of slippage of a polymer melt within 100 nm of a solid surface, under simple shear, are reported. In the case of a high molecular weight polydimethylsiloxane (PDMS) interacting weakly with the solid surface, a sharp transition between weak and strong slippage is observed as a function of shear stress. For strong polymer-surface interactions, slippage is highly reduced, and no transition is observed. The results are compared to a theoretical model recently proposed by Brochard and de Gennes.