373 research outputs found
Automated detectionof very low surface brightness galaxiesin the Virgo cluster
We report the automatic detection of a new sample of very low surface
brightness (LSB) galaxies, likely members of the Virgo cluster. We introduce
our new software, {\tt DeepScan}, that has been designed specifically to detect
extended LSB features automatically using the DBSCAN algorithm. We demonstrate
the technique by applying it over a 5 degree portion of the Next-Generation
Virgo Survey (NGVS) data to reveal 53 low surface brightness galaxies that are
candidate cluster members based on their sizes and colours. 30 of these sources
are new detections despite the region being searched specifically for LSB
galaxies previously. Our final sample contains galaxies with and , making them some of the
faintest known in Virgo. The majority of them have colours consistent with the
red sequence, and have a mean stellar mass of
assuming cluster membership. After using {\tt ProFit} to fit S\'ersic profiles
to our detections, none of the new sources have effective radii larger than 1.5
Kpc and do not meet the criteria for ultra-diffuse galaxy (UDG) classification,
so we classify them as ultra-faint dwarfs.Comment: 16 pages, 14 figures, Accepted for publication in MNRAS 201
Decision systems redux
Looking forward, the goal of this article is to stimulate discussion and encourage novel thinking about computerized systems. Looking back 60 years, this article reviews definitions and research related to the decision system concept and associated terms like automated decision system (ADS) and decision support system (DSS). This historical perspective differentiates and expands the phenomenon of a decision system to create a modern context for future applied and scholarly research and development. Looking forward, more automated decision systems will make and implement decisions. Analytics will be embedded in decision systems, decision support will proliferate, and decision systems will be part of ambient intelligent environments. This article expands the horizon for decision-making research by reviving the concept of a decision system. Perhaps this article will lead researchers to study decision systems more comprehensively
Detecting Regulatory Mechanisms in Endocrine Time Series Measurements
The regulatory mechanisms underlying pulsatile secretion are complex, especially as it is partly controlled by other hormones and the combined action of multiple agents. Regulatory relations between hormones are not directly observable but may be deduced from time series measurements of plasma hormone concentrations. Variation in plasma hormone levels are the resultant of secretion and clearance from the circulation. A strategy is proposed to extract inhibition, activation, thresholds and circadian synchronicity from concentration data, using particular association methods. Time delayed associations between hormone concentrations and/or extracted secretion pulse profiles reveal the information on regulatory mechanisms. The above mentioned regulatory mechanisms are illustrated with simulated data. Additionally, data from a lean cohort of healthy control subjects is used to illustrate activation (ACTH and cortisol) and circadian synchronicity (ACTH and TSH) in real data. The simulation and the real data both consist of 145 equidistant samples per individual, matching a 24-hr time span with 10 minute intervals. The results of the simulation and the real data are in concordance
Heaviness, health and happiness: a cross-sectional study of 163 066 UK Biobank participants
<b>Background</b><p></p> Obesity is known to increase the risk of many diseases and reduce overall quality of life. This study examines the relationship with self-reported health (SRH) and happiness.<p></p>
<b>Methods</b> <p></p>We conducted a cross-sectional study of the 163 066 UK Biobank participants who completed the happiness rating. The association between adiposity and SRH and happiness was examined using logistic regression. SRH was defined as good (excellent, good), or poor (fair, poor). Self-reported happiness was defined as happy (extremely, very, moderately) or unhappy (moderately, very, extremely). <p></p>
<b>Results</b> <p></p>Poor health was reported by 44 457 (27.3%) participants. The adjusted ORs for poor health were 3.86, 2.92, 2.60 and 6.41 for the highest, compared with lowest, deciles of Body Mass Index, waist circumference, waist to hip ratio and body fat percent, respectively. The associations were stronger in men (p<0.001). Overall, 7511 (4.6%) participants felt unhappy, and only class III obese participants were more likely to feel unhappy (adjusted OR 1.33, 95% CI 1.15 to 1.53, p<0.001) but the associations differed by sex (p<0.001). Among women, there was a significant association between unhappiness and all levels of obesity. By contrast, only class III obese men had significantly increased risk and overweight and class I obese men were less likely to be unhappy. <p></p>
<b>Conclusions</b><p></p>Obesity impacts adversely on happiness as well as health, but the association with unhappiness disappeared after adjustment for self-reported health, indicating this may be mediated by health. Compared with obese men, obese women are less likely to report poor health, but more likely to feel unhappy. <p></p>
The effect of COVID19 public health restrictions on the health of people with musculoskeletal conditions and symptoms : the CONTAIN study
Funding This work was supported by Versus Arthritis [Grant Number: 20748] and the British Society for Rheumatology. The funding for the original studies included were from Versus Arthritis (MAmMOTH) and the British Society for Rheumatology (BSRBR-AS and BSR-PsA). Daniel Whibley is supported by a Versus Arthritis Foundation Fellowship [Grant Number 21742] Acknowledgements We are grateful to help from staff at the National Ankylosing Spondylitis Society and specifically to patient partners Lynne Laidlaw (for help with designing questionnaire) and Susan Davis (for commenting on the manuscript). The authors do not report any conflicts of interest. GJM conceived the idea for the study and all authors were involved in the detailed planning. MH, KK, EM-B and MB were responsible for obtaining ethics and research governance approvals. MB undertook the analysis which was independently verified by GTJ. GJM, with input from MB, drafted the manuscript, and all authors contributed important intellectual content via written comments. We thank Linda Dean for comments on the manuscript. Data Availability Statement The data within the article which relate to the collection of BSR register data are owned by the BSR – access to these data are subject to application being made to the BSR: Registers (rheumatology.org.uk) . For other data in the article, application can be made for access to the data by contacting the corresponding author.Peer reviewedPublisher PD
RNA-Seq identifies SPGs as a ventral skeletal patterning cue in sea urchins
The sea urchin larval skeleton offers a simple model for formation of developmental patterns. The calcium carbonate skeleton is secreted by primary mesenchyme cells (PMCs) in response to largely unknown patterning cues expressed by the ectoderm. To discover novel ectodermal cues, we performed an unbiased RNA-Seq-based screen and functionally tested candidates; we thereby identified several novel skeletal patterning cues. Among these, we show that SLC26a2/7 is a ventrally expressed sulfate transporter that promotes a ventral accumulation of sulfated proteoglycans, which is required for ventral PMC positioning and skeletal patterning. We show that the effects of SLC perturbation are mimicked by manipulation of either external sulfate levels or proteoglycan sulfation. These results identify novel skeletal patterning genes and demonstrate that ventral proteoglycan sulfation serves as a positional cue for sea urchin skeletal patterning
Disentangling water, ion and polymer dynamics in an anion exchange membrane
Semipermeable polymeric anion exchange membranes are essential for separation, filtration and energy conversion technologies including reverse electrodialysis systems that produce energy from salinity gradients, fuel cells to generate electrical power from the electrochemical reaction between hydrogen and oxygen, and water electrolyser systems that provide H2 fuel. Anion exchange membrane fuel cells and anion exchange membrane water electrolysers rely on the membrane to transport OH− ions between the cathode and anode in a process that involves cooperative interactions with H2O molecules and polymer dynamics. Understanding and controlling the interactions between the relaxation and diffusional processes pose a main scientific and critical membrane design challenge. Here quasi-elastic neutron scattering is applied over a wide range of timescales (100–103 ps) to disentangle the water, polymer relaxation and OH− diffusional dynamics in commercially available anion exchange membranes (Fumatech FAD-55) designed for selective anion transport across different technology platforms, using the concept of serial decoupling of relaxation and diffusional processes to analyse the data. Preliminary data are also reported for a laboratory-prepared anion exchange membrane especially designed for fuel cell applications
The Future of American Sentencing: A National Roundtable on Blakely
In the wake of the dramatic Supreme Court decision in Blakely v. Washington, Stanford Law School convened an assembly of the most eminent academic and professional sentencing experts in the country to jointly assess the meaning of the decision and its implications for federal and state sentencing reform. The event took place on October 8 and 9, just a few months after Blakely came down and the very week that the Supreme Court heard the arguments in United States v. Booker and United States v. Fanfan, the cases that will test Blakely\u27s application to the Federal Sentencing Guidelines. Thus the Roundtable offered these experts an intellectual breathing space at a crucial point in American criminal law.
The event was built around six sessions, with shifting panels of participants doing brief presentations on the subject of the session, and with others then joining in the discussion. We are pleased that FSR is able to publish this version of the proceedings of the event-a condensed and edited transcript of the sessions
HIV outbreaks among people who inject drugs in Europe, North America and Israel
During 2011–16, HIV outbreaks occurred among people who inject drugs (PWID) in Canada (southeastern Saskatchewan), Greece (Athens), Ireland (Dublin), Israel (Tel Aviv), Luxembourg, Romania (Bucharest), Scotland (Glasgow), and USA (Scott County, Indiana). Factors common to many of these outbreaks included community economic problems, homelessness, and changes in drug injection patterns. The outbreaks differed in size (from under 100 to over 1000 newly reported HIV cases among PWID) and in the extent to which combined prevention had been implemented before, during, and after the outbreaks. Countries need to ensure high coverage of HIV prevention services and coverage higher than the current UNAIDS recommendation might be needed in areas in which short acting drugs are injected. In addition, monitoring of PWID with special attention for changing drug use patterns, risk behaviours, and susceptible subgroups (eg, PWID experiencing homelessness) needs to be in place to prevent or rapidly detect and contain new HIV outbreaks
The Continuing Slow Decline of AG Pegasi
We analyze optical and ultraviolet observations of the symbiotic binary AG
Pegasi acquired during 1992-97. The bolometric luminosity of the hot component
declined by a factor of 2-3 from 1980-1985 to 1997. Since 1992, the effective
temperature of the hot component may have declined by 10%-20%, but this decline
is comparable to the measurement errors. Optical observations of H-beta and He
I emission show a clear illumination effect, where high energy photons from the
hot component ionize the outer atmosphere of the red giant. Simple illumination
models generally account for the magnitude of the optical and ultraviolet
emission line fluxes. High ionization emission lines - [Ne V], [Mg V], and [Fe
VII] - suggest mechanical heating in the outer portions of the photoionized red
giant wind. This emission probably originates in a low density region
30-300 AU from the central binary.Comment: 17 pages, 7 pages, 5 tables; to be published in the Astronomical
Journal, July 200
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