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The Cape Parrot Poicephalus robustus is a habitat specialist, restricted to forest patches in the Eastern Cape (EC), KwaZulu-Natal (KZN) and Limpopo provinces of South Africa. Recent census estimates suggest that there are less than 1,600 parrots left in the wild, although historical data suggest that the species was once more numerous. Fragmentation of the forest biome is strongly linked to climate change and exploitation of the forest by the timber industry. We examine the subpopulation structure and connectivity between fragmented populations across the distribution of the species. Differences in historical and contemporary genetic structure of Cape Parrots is examined by including both modern samples, collected from 1951 to 2014, and historical samples, collected from 1870 to 1946. A total of 114 individuals (historical = 29; contemporary = 85) were genotyped using 16 microsatellite loci. We tested for evidence of partitioning of genotypes at both a temporal and spatial scales by comparing shifts in allelic frequencies of historical (1870–1946) and contemporary (1951–2014) samples across the distribution of the species. Tests for population bottlenecks were also conducted to determine if anthropogenic causes are the main driver of population decline in this species. Analyses identified three geographically correlated genetic clusters. A southern group restricted to forest patches in the EC, a central group including birds from KZN and a genetically distinct northern Limpopo cluster. Results suggest that Cape Parrots have experienced at least two population bottlenecks. An ancient decline during the mid-Holocene (∼ 1,800-3,000 years before present) linked to climate change, and a more recent bottleneck, associated with logging of forests during the early 1900s. This study highlights the effects of climate change and human activities on an endangered species associated with the naturally fragmented forests of eastern South Africa. These results will aid conservation authorities with the planning and implementation of future conservation initiatives. In particular, this study emphasises the Eastern Cape mistbelt forests as an important source population for the species and calls for stronger conservation of forest patches in South Africa to promote connectivity of forest taxa.
The patient portal may be an effective method for administering surveys regarding participant research experiences but has not been systematically studied.
We evaluated 4 methods of delivering a research participant perception survey: mailing, phone, email, and patient portal. Participants of research studies were identified (n=4013) and 800 were randomly selected to receive a survey, 200 for each method. Outcomes included response rate, survey completeness, and cost.
Among those aged <65 years, response rates did not differ between mail, phone, and patient portal (22%, 29%, 30%, p>0.07). Among these methods, the patient portal was the lowest-cost option. Response rates were significantly lower using email (10%, p<0.01), the lowest-cost option. In contrast, among those aged 65+ years, mail was superior to the electronic methods (p<0.02).
The patient portal was among the most effective ways to reach research participants, and was less expensive than surveys administered by mail or telephone.
The origin of red supergiant mass loss still remains to be unveiled. Characterising the formation loci and the dust distribution in the first stellar radii above the surface is key to understand the initiation of the mass loss phenomenon. Polarimetric interferometry observations in the near-infrared allowed us to detect an inner dust atmosphere located only 0.5 stellar radius above the photosphere of Betelgeuse. We modelled these observations and compare them with visible polarimetric measurements to discuss the dust distribution properties.
To examine temporal trends and determinants of discretionary salt use in the USA.
Multiple logistic regression was used to assess temporal trends in discretionary salt use at the table and during home cooking/preparation, adjusting for demographic characteristics, using data from the National Health and Nutrition Examination Survey 2003–2012. Prevalence and determinants of discretionary salt use in 2009–2012 were also examined.
Participants answered salt use questions after completing a 24 h dietary recall in a mobile examination centre.
Nationally representative sample of non-institutionalized US children and adults, aged ≥2 years.
From 2003 to 2012, the proportion of the population who reported using salt ‘very often’ declined; from 18 % to 12 % for use at the table (P<0·01) and from 42 % to 37 % during home cooking (P<0·02). While one-third of the population reported never adding salt at the table, most used it during home cooking/preparation (93 %). Use of discretionary salt was least commonly reported among young children and older adults and demographic and health subgroups at risk of CVD.
While most people reported using salt during home cooking/preparation, a minority reported use at the table. Reported ‘very often’ discretionary salt use has declined. That discretionary salt use is less common among those at risk of CVD suggests awareness of messages to limit Na intake.
Poor adherence to recommended intake protocols is common and a top challenge for micronutrient powder (MNP) programmes globally. Identifying modifiable predictors of intake adherence could inform the design and implementation of MNP projects.
We assessed high MNP intake adherence among children who had received MNP ≥2 months ago and consumed ≥1 sachet (n 771). High MNP intake adherence was defined as maternal report of child intake ≥45 sachets. We used logistic regression to assess demographic, intervention components and perception-of-use factors associated with high MNP intake.
Four districts of Nepal piloting an integrated infant and young child feeding and MNP project.
Children aged 6–23 months were eligible to receive sixty MNP sachets every 6 months with suggested intake of one sachet daily for 60 d. Cross-sectional surveys representative of children aged 6–23 months were conducted.
Receiving a reminder card was associated with increased odds for high intake (OR=2·18, 95 % CI 1·14, 4·18); exposure to other programme components was not associated with high intake. Mothers perceiving ≥1 positive effects in their child after MNP use was also associated with high intake (OR=6·55, 95 % CI 4·29, 10·01). Perceiving negative affects was not associated; however, the child not liking the food with MNP was associated with lower odds of high intake (OR=0·12, 95 % CI 0·08, 0·20).
Behaviour change intervention strategies tailored to address these modifiable predictors could potentially increase MNP intake adherence.
Massive evolved stars contribute to the chemical enrichment of the Galaxy. When they die as supernova but also through their mass loss during the several thousands of years of their red supergiant (RSG) phase. Unfortunately the mass loss mechanism remains poorly understood. Detailed study of the CSE and photosphere of nearby RSGs is required to constrain this scenario.
Betelgeuse is the closest RSG (197 pc) and therefore has a large apparent diameter (~ 42 mas) which makes it a very interesting target. For several years, our team has lead a multi-wavelength and multi-scale observing program to characterize its mass loss. We will review here our recent results in near-infrared interferometry.
To examine the association between overweight and obesity and serum ferritin among women of reproductive age (15–49 years) in Nicaragua, considering the effect of α1-acid glycoprotein (AGP), a marker of inflammation.
We analysed data from the 2004–05 Nicaraguan Integrated Surveillance System for Nutrition Interventions. Three logistic regression models were analysed with low serum ferritin (<15 μg/l) as the dependent variable: (i) overweight or obese status and covariates; (ii) model 1 plus AGP; and (iii) model 1 restricted to only women with normal AGP levels (≤1·0 g/l).
Included in this analysis were 832 non-pregnant mother/caregivers (15–49 years) surveyed in 2004–2005.
In the sample, prevalence of overweight and obesity was 31·8 % and 19·2 %, respectively, and 27·6 % had low serum ferritin. In model 1, the adjusted OR of low serum ferritin was 0·74 (95 % CI 0·52, 1·05) for overweight women and 0·42 (95 % CI 0·26, 0·65) for obese women. In model 2, AGP was significantly independently associated with low serum ferritin (adjusted OR=0·56, 95 % CI 0·34, 0·92) while the adjusted OR for overweight and obesity were largely unchanged. Excluding women with elevated AGP did not appreciably affect the relationship between overweight or obesity and low serum ferritin (model 3).
Overall, in this population of reproductive-age women, obese women were less likely to have low serum ferritin levels, and this was independent of inflammation as measured by AGP.
Electroconvulsive therapy (ECT) is an effective treatment for depression but the extent and persistence of cognitive side-effects remain uncertain. It has been reported that there is little evidence that impairments last longer than up to 15 days post-ECT. However, relatively few studies have followed patients for even as long as 1 month post-ECT. Here we report results from a brief cognitive battery given prior to ECT and repeated five times up to 6 months post-ECT.
In a retrospective case-note study of routinely collected clinical data 126 patients treated with ECT completed two neuropsychological tests [Cambridge Neuropsychological Test Automated Battery (CANTAB) spatial recognition memory (SRM) and Mini Mental State Examination (MMSE)] and two subjective reports of memory function, prior to ECT. Patients were reassessed following ECT and at 1, 3 and 6 months post-ECT although not all patients completed all assessments.
Performance relative to pre-ECT baseline was significantly poorer at each post-ECT assessment up to 3 months post-ECT using the CANTAB SRM, but was improved at 6 months. Conversely, MMSE score showed improvements relative to baseline from 1 month post-ECT. Mood and subjective memory scores improved following ECT and were correlated with one another, but not with either neuropsychological measure.
The CANTAB SRM task revealed reversible cognitive deficiencies relative to a pre-ECT baseline for at least 3 months following ECT, while MMSE score and patients' subjective reports showed only improvement. Visuospatial memory scores eventually exceeded baseline 6 months post-ECT.
We present detailed models of the edge-on protoplanetary disk ESO Hα 569 (SSTgbs J111110.7-764157) from resolved scattered light images from HST and a complete spectral energy distribution. Data was obtained as part of an HST campaign to catalogue edge-on disks around young stars in nearby star forming regions (HST program 12514, PI: Karl Stapelfeldt). We confirm that this object is an optically thick edge-on disk around a young star with an outer radius of 125 AU. Using full radiative transfer models, we probe the distribution of dust grains and overall shape of the disk (inclination, scale height, dust mass, maximum particle size, inner radius, flaring exponent and surface/volume density exponent).
We present new high-resolution observations and modeling of SSTtau J042021+ 281349, a 400 AU-radius edge-on protoplanetary disk. We have gathered visible and near-infrared scattered light images of the system with the Hubble Space Telescope and Keck adaptive optics system, as well as a 1.3 mm continuum map with CARMA. Compared to the well-known HH 30 disk, this new system is remarkable because of its spectacular bipolar jet and the high degree of lateral symmetry of the disk. Indeed, we argue that this system is a “cleaner” prototype for edge-on disks. In addition, the apparent achromaticity of dust properties (most notably the almost grey opacity law) from the visible to the near-infrared in this disk suggests that it is in an advanced stage of dust evolution.
Edge-on, optically thick circumstellar disks have been previously imaged at subarcsecond resolution around about a dozen nearby young stellar objects. In these systems the central star is occulted from direct view, bright star image artifacts are absent, and the disk reflected light is clearly seen. Comparison of Hubble Space Telescope (HST) edge-on disk images with scattered light models has allowed key disk structural parameters and dust grain properties to be determined. Edge-on disks have been systematically undercounted to date: while 10% of young stars should statistically be occulted by their disk, the observed frequency is much less. Thus there is a significant potential for discovering and imaging new examples. Spitzer Space Telescope legacy science programs have provided the first good spectral energy distribution (SED) measurements for the previously known edge-on disks. These can be used as templates to identify new candidates in far-infrared survey datasets.
We report on the results of our HST program to image twenty-one edge-on disk candidates mostly selected from their SEDs. Eleven are well-resolved with radii ranging from 30-400 AU, nine for the first time and six showing highly collimated jets. Outstanding individual sources include a large and symmetric new template object, a highly flattened disk not accreting onto its central star, and an asymmetric disk with a misaligned jet which likely traces tidal perturbations in a binary system. Follow-up work to obtain ancillary data and perform scattered light modeling of the most symmetric disks is now being pursued. The results of this program will guide a new round of searches for these rare but important snapshots of protoplanetary disk evolution.
The violent convective motions, low surface gravity, and high brightness of red supergiants combine to trigger an intense stellar wind. As the distance from the star increases, the standard scenario is that the ejected material forms molecules, then dust particles. But this general picture is still fragmentary. Our goal is to assemble a better understanding of mass loss in Betelgeuse, considered as a prototype for its class, from its photosphere to the interface of its wind with the interstellar medium. Thanks to its proximity ( ≈ 197 pc), it is ideally suited for such a detailed study. Over the past few years, our team obtained an extensive set of observations of Betelgeuse from high angular resolution instruments, probing a broad range of spatial scales: 1) interferometric imaging of its photosphere and close envelope in the near- and thermal-IR domains (IOTA/IONIC), 2) adaptive optics “lucky imaging” of its compact molecular envelope (VLT/NACO, 1.0–2.2 μm), and 3) diffraction-limited imaging of its dusty envelope (VLT/VISIR, 8–20 μm). From our interferometric data, we detect the presence of spots at the surface of the star, as well as CO and H2O molecules, and dust particles close to the star. Within 6 R⋆, the flux distribution of the envelope is compatible with the presence of the CN molecule. At a few arcseconds from the central star, we observe a complex dusty envelope probably containing O-rich dust (e.g. silicates, alumina). We present an overview of these recent observational results and ongoing work. They provide new hints on the physical and chemical mechanisms through which Betelgeuse interacts with its environment.
We present the results of the analysis of our recent interferometric observations of
Betelgeuse, using the AMBER instrument of the VLTI. Using the medium spectral resolution
mode (R ~ 1500) we detected the presence of the water vapour and
carbon monoxide (CO) molecules in the H and K bands. We also derived the photospheric
angular diameter in the continuum. By analysing the depth of the molecular lines and the
interferometric visibilities, we derived the column densities of the molecules, as well as
the temperature and the size of the corresponding regions in the atmosphere of Betelgeuse
(the MOLsphere) using a single shell model around the photosphere. Our results confirm the
findings by Perrin et al. (2004)
and Ohnaka et al. (2011) that the
H2O and CO molecules are distributed around Betelgeuse in a MOLsphere
extending to approximately 1.3 times the star’s photospheric radius.
We report on a long-term monitoring of the cool supergiant Betelgeuse, using the NARVAL and ESPaDOnS high-resolution spectropolarimeters, respectively installed at Telescope Bernard Lyot (Pic du Midi Observatory, France) and at the Canada-France-Hawaii Telescope (Mauna Kea Observatory, Hawaii). The data set, constituted of circularly polarized (Stokes V) and intensity (Stokes I) spectra, was collected between 2010 and 2012. We investigate here the temporal evolution of magnetic field, convection and temperature at photospheric level, using simultaneous measurements of the longitudinal magnetic field component, the core emission of the Ca II infrared triplet, the line-depth ratio of selected photospheric lines and the radial velocity of the star.
The first UK epizootic of highly pathogenic (HP) H5N1 influenza in wild birds occurred in 2008, in a population of mute swans that had been the subject of ornithological study for decades. Here we use an innovative combination of ornithological, phylogenetic and immunological approaches to investigate the ecology and age structure of HP H5N1 in nature. We screened samples from swans and waterbirds using PCR and sequenced HP H5N1-positive samples. The outbreak's origin was investigated by linking bird count data with a molecular clock analysis of sampled virus sequences. We used ringing records to reconstruct the age-structure of outbreak mortality, and we estimated the age distribution of prior exposure to avian influenza. Outbreak mortality was low and all HP H5N1-positive mute swans in the affected population were <3 years old. Only the youngest age classes contained an appreciable number of individuals with no detectable antibody responses to viral nucleoprotein. Phylogenetic analysis indicated that the outbreak strain circulated locally for ∼1 month before detection and arrived when the immigration rate of migrant waterbirds was highest. Our data are consistent with the hypothesis that HP H5N1 epizootics in wild swans exhibit limited mortality due to immune protection arising from previous exposure. Our study population may represent a valuable resource for investigating the natural ecology and epidemiology of avian influenza.