152 research outputs found
EPIC 220204960: a quadruple star system containing two strongly interacting eclipsing binaries
We present a strongly interacting quadruple system associated with the K2 target EPIC 220204960. The K2 target itself is a K-p = 12.7-mag star at T-eff -6100 K, which we designate as 'B-N' ( blue northerly image). The host of the quadruple system, however, is a K-p -17-mag star with a composite M-star spectrum, which we designate as 'R-S' ( red southerly image). With a 3.2-arcsec separation and similar radial velocities and photometric distances, 'B-N' is likely physically associated with 'R-S', making this a quintuple system, but that is incidental to our main claim of a strongly interacting quadruple system in ` R-S'. The two binaries in 'R-S' have orbital periods of 13.27 and 14.41 d, respectively, and each has an inclination angle of >= 89 degrees. From our analysis of radial-velocity ( RV) measurements, and of the photometric light curve, we conclude that all four stars are very similar with masses close to 0.4M(circle dot). Both of the binaries exhibit significant eclipse-timing variations where those of the primary and secondary eclipses 'diverge' by 0.05 d over the course of the 80-d observations. Via a systematic set of numerical simulations of quadruple systems consisting of two interacting binaries, we conclude that the outer orbital period is very likely to be between 300 and 500 d. If sufficient time is devoted to RV studies of this faint target, the outer orbit should be measurable within a year
Psychosocial interventions for people with dementia: a synthesis of systematic reviews
Objectives: Over the last 10 years there has been a multitude of studies of psychosocial interventions for people with dementia. However, clinical services face a dilemma about which intervention should be introduced into clinical practice because of the inconsistency in some of the findings between different studies and the differences in the study qualities and trustworthiness of evidence. There was a need to provide a comprehensive summary of the best evidence to illustrate what works.
Methods: A review of the systematic reviews of psychosocial interventions in dementia published between January 2010 and February 2016 was conducted.
Results: Twenty-two reviews (8 physical, 7 cognitive, 1 physical/cognitive and 6 other psychosocial interventions) with a total of 197 unique studies met the inclusion criteria. Both medium to longer-term multi-component exercise of moderate to high intensity, and, group cognitive stimulation consistently show benefits. There is not sufficient evidence to determine whether psychological or social interventions might improve either mood or behaviour due to the heterogeneity of the studies and interventions included in the reviews.
Conclusion: There is good evidence that multi-component exercise with sufficient intensity improves global physical and cognitive functions and activities of daily living skills. There is also good evidence that group based cognitive stimulation improves cognitive functions, social interaction and quality of life. This synthesis also highlights the potential importance of group activities to improve social integration for people with dementia. Future research should investigate longer-term specific outcomes, consider the severity and types of dementia, and investigate mechanisms of change
Gaia Data Release 2: All-sky classification of high-amplitude pulsating stars
Out of the 1.69 billion sources in the Gaia Data Release 2 (DR2), more than half a million are published with photometric time series that exhibit light variations during 22 months of observation. An all-sky classification of common high-amplitude pulsators (Cepheids, long-period variables, Delta Scuti / SX Phoenicis, and RR Lyrae stars) is provided for stars with brightness variations greater than 0.1 mag in the G band. A semi-supervised classification approach was employed, firstly training multi-stage Random Forest classifiers with sources of known types in the literature, followed by a preliminary classification of the Gaia data and a second training phase that included a selection of the first classification results to improve the representation of some classes, before the application of the improved classifiers to the Gaia data. Dedicated validation classifiers were used to reduce the level of contamination in the published results. A relevant fraction of objects were not yet sufficiently sampled for reliable Fourier series decomposition, so classifiers were based on features derived from statistics of photometric time series in the G, BP, and RP bands, as well as from some astrometric parameters. The published classification results include 195,780 RR Lyrae stars, 150,757 long-period variables, 8550 Cepheids, and 8882 Delta Scuti / SX Phoenicis stars. All of these results represent candidates, whose completeness and contamination are described as a function of variability type and classification reliability. Results are expressed in terms of class labels and classification scores, which are available in the vari_classifier_result table of the Gaia archive
Transcriptomics of Parental Care in the HypothalamicâSeptal Region of Female Zebra Finch Brain
(1) Background: The objective of this study was to uncover genomic causes of parental care. Since birds do not lactate and, therefore, do not show the gene expressional changes required for lactation, we investigate gene expression associated with parenting in caring and non-caring
females in an avian species, the small passerine bird zebra finch (Taeniopygia guttata). Here, we compare expression patterns in the hypothalamicâseptal region since, previously, we showed that this area is activated in parenting females. (2) Methods: Transcriptome sequencing was first applied in a dissected part of the zebra finch brain related to taking care of the nestlings as compared to a
control group of social pairs without nestlings. (3) Results: We found genes differentially expressed
between caring and non-caring females. When introducing a log2fold change threshold of 1.5, 13 annotated genes were significantly upregulated in breeding pairs, while 39 annotated genes were downregulated. Significant enrichments of dopamine and acetylcholine biosynthetic processes
were identified among upregulated pathways, while pro-opiomelanocortin and thyroid hormone pathways were downregulated, suggesting the importance of these systems in parental care. Network analysis further suggested neuro-immunological changes in mothers. (4) Conclusions: The results confirm the roles of several hypothesized major pathways in parental care, whereas novel pathways
are also proposed
Index finger movement imitation by human neonates: motivation, learning, and left-hand preference
Imitation of a fine motor movement, index finger protrusion, was examined in 39 neonates using an ethologically based objective coding system. Results confirmed that imitation of finger movements exists, and infants demonstrated "learning" as imitation developed through an incomplete imitation stage. Neonatal imitation was more frequently left-handed, an early sign of laterality in motivation to be investigated further. The existence of index finger imitation in human neonates indicates that volitional control of individuated finger movements develops much earlier than previously thought. The differential increase of index finger protrusion movements during the imitation periods suggests that this behavior is not an automatic response triggered by general arousal but instead is a true indicator of purposeful neonatal imitation
Drosophila Uri, a PP1α binding protein, is essential for viability, maintenance of DNA integrity and normal transcriptional activity
<p>Abstract</p> <p>Background</p> <p>Protein phosphatase 1 (PP1) is involved in diverse cellular processes, and is targeted to substrates via interaction with many different protein binding partners. PP1 catalytic subunits (PP1c) fall into PP1α and PP1ÎČ subfamilies based on sequence analysis, however very few PP1c binding proteins have been demonstrated to discriminate between PP1α and PP1ÎČ.</p> <p>Results</p> <p>URI (unconventional prefoldin RPB5 interactor) is a conserved molecular chaperone implicated in a variety of cellular processes, including the transcriptional response to nutrient signalling and maintenance of DNA integrity. We show that <it>Drosophila </it>Uri binds PP1α with much higher affinity than PP1ÎČ, and that this ability to discriminate between PP1c forms is conserved to humans. Most Uri is cytoplasmic, however we found some protein associated with active RNAPII on chromatin. We generated a <it>uri </it>loss of function allele, and show that <it>uri </it>is essential for viability in <it>Drosophila</it>. <it>uri </it>mutants have transcriptional defects, reduced cell viability and differentiation in the germline, and accumulate DNA damage in their nuclei.</p> <p>Conclusion</p> <p>Uri is the first PP1α specific binding protein to be described in <it>Drosophila</it>. Uri protein plays a role in transcriptional regulation. Activity of <it>uri </it>is required to maintain DNA integrity and cell survival in normal development.</p
Representativeness of microsatellite distributions in genomes, as revealed by 454 GS-FLX Titanium pyrosequencing
<p>Abstract</p> <p>Background</p> <p>Microsatellites are markers of choice in population genetics and genomics, as they provide useful insight into patterns and processes as diverse as genome evolutionary dynamics and demographic processes. The acquisition of microsatellites through multiplex-enriched libraries and 454 GS-FLX Titanium pyrosequencing is a promising new tool for the isolation of new markers in unknown genomes. This approach can also be used to evaluate the extent to which microsatellite-enriched libraries are representative of the genome from which they were isolated. In this study, we deciphered potential discrepancies in microsatellite content recovery for two reference genomes (<it>Apis mellifera </it>and <it>Danio rerio</it>), selected on the basis of their extreme heterogeneity in terms of the proportions and distributions of microsatellites on chromosomes.</p> <p>Results</p> <p>The <it>A. mellifera </it>genome, in particular, was found to be highly heterogeneous, due to extremely high rates of recombination, with hotspots, but the only bias consistently introduced into pyrosequenced multiplex-enriched libraries concerned sequence length, with the overrepresentation of sequences 160 to 320 bp in length. Other deviations from expected proportions or distributions of motifs on chromosomes were observed, but the significance and intensity of these deviations was mostly limited. Furthermore, no consistent adverse competition between multiplexed probes was observed during the motif enrichment phase.</p> <p>Conclusions</p> <p>This approach therefore appears to be a promising strategy for improving the development of microsatellites, as it introduces no major bias in terms of the proportions and distribution of microsatellites.</p
A Mixed Blessing: Market-Mediated Religious Authority in Neopaganism
This research explores how marketplace dynamics affect religious authority in the context of Neopagan religion. Drawing on an interpretivist study of Wiccan practitioners in Italy, we reveal that engagement with the market may cause considerable, ongoing tensions, based on the inherent contradictions that are perceived to exist between spirituality and commercial gain. As a result, market success is a mixed blessing that can increase religious authority and influence, but is just as likely to decrease authority and credibility. Using an extended case study method, we propose a theoretical framework that depicts the links between our informantsâ situated experiences and the macro-level factors affecting religious authority as it interacts with market-mediated dynamics at the global level. Overall, our study extends previous work in macromarketing that has looked at religious authority in the marketplace) and how the processes of globalization are affecting religion
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