The history of stellar metallicity in a simulated disc galaxy

We explore the chemical distribution of stars in a simulated galaxy. Using simulations of the same initial conditions but with two different feedback schemes (McMaster Unbiased Galaxy Simulations – MUGS – and Making Galaxies in a Cosmological Context – MaGICC), we examine the features of the age–metallicity relation (AMR), and the three-dimensional age– [Fe/H]–[O/Fe] distribution, both for the galaxy as a whole and decomposed into disc, bulge, halo and satellites. The MUGS simulation, which uses traditional supernova feedback, is replete with chemical substructure. This substructure is absent from the MaGICC simulation, which includes early feedback from stellar winds, a modified initial mass function and more efficient feedback. The reduced amount of substructure is due to the almost complete lack of satellites in MaGICC. We identify a significant separation between the bulge and disc AMRs, where the bulge is considerably more metal-rich with a smaller spread in metallicity at any given time than the disc. Our results suggest, however, that identifying the substructure in observations will require exquisite age resolution, of the order of 0.25 Gyr. Certain satellites show exotic features in the AMR, even forming a ‘sawtooth’ shape of increasing metallicity followed by sharp declines which correspond to pericentric passages. This fact, along with the large spread in stellar age at a given metallicity, compromises the use of metallicity as an age indicator, although alpha abundance provides a more robust clock at early times. This may also impact algorithms that are used to reconstruct star formation histories from resolved stellar populations, which frequently assume a monotonically increasing AMR

Infrared nano-spectroscopy and imaging of collective superfluid excitations in conventional and high-temperature superconductors

We investigate near-field infrared spectroscopy and superfluid polariton imaging experiments on conventional and unconventional superconductors. Our modeling shows that near-field spectroscopy can measure the magnitude of the superconducting energy gap in Bardeen-Cooper-Schrieffer-like superconductors with nanoscale spatial resolution. We demonstrate how the same technique can measure the c-axis plasma frequency, and thus the c-axis superfluid density, of layered unconventional superconductors with a similar spatial resolution. Our modeling also shows that near-field techniques can image superfluid surface mode interference patterns near physical and electronic boundaries. We describe how these images can be used to extract the collective mode dispersion of anisotropic superconductors with sub-diffractional spatial resolution.Comment: 11 pages, 8 figure

Evolving Project ECHO: delivery of pediatric pain core competency learning for interprofessional healthcare providers

IntroductionHealthcare providers (HCPs) practicing in community settings are critical to improving access to pain care, yet there are significant gaps in training opportunities designed for interprofessional learners. Project Extension for Community Healthcare Outcomes (Project ECHO®) is an established model for delivering online HCP education through virtual clinics and cultivating a community of practice. However, to our knowledge, the integration of pain core competency education into the ECHO® model has not been previously attempted. This innovation could enhance the ECHO® model while also addressing the growing calls for more accessible interprofessional pain curricula. This paper describes efforts to implement and evaluate core competency curricula within the context of Pediatric Project ECHO for Pain, one of the first pediatric-pain focused ECHO programs in the world.MethodsNeeds assessments informed curricula development. The first delivered core competency model consisted of synchronous webinar-style sessions while the second model included a mixture of asynchronous (eLearning course) and synchronous (virtual clinical debrief) elements. A convenience sample of HCPs was recruited from ECHO program registrants. Participants completed baseline and follow-up surveys to assess core competency acceptability as well as impact on knowledge and self-efficacy related to managing pediatric pain. Usability of the eLearning platform (model 2 only) was also evaluated. Surveys used 5-point Likert scales to capture outcomes. A priori targets included mean scores ≥4/5 for acceptability and ≥80% of learners reporting knowledge and self-efficacy improvements. The study received local research ethics approval.ResultsThe core competency was found to be highly acceptable to interprofessional learners (n = 31) across delivery models, surpassing a priori targets. Specifically, it was characterized as a worthwhile and satisfactory experience that was helpful in supporting learning. The core competency was also associated with improvements in knowledge and self-efficacy by 97% and 90% of learners, respectively. The eLearning platform was reported to have high usability with clinically realistic cases (100% of respondents) that were helpful to inform care delivery (94% of respondents).ConclusionThe integration of core competency learning within the Project ECHO® model was a successful approach to deliver pediatric pain education to interprofessional HCPs

A 2-Secure Code with Efficient Tracing Algorithm

A 2-secure code with efficient tracing algorith

The effects of changes in the order of verbal labels and numerical values on children's scores on attitude and rating scales

Research with adults has shown that variations in verbal labels and numerical scale values on rating scales can affect the responses given. However, few studies have been conducted with children. The study aimed to examine potential differences in children’s responses to Likert-type rating scales according to their anchor points and scale direction, and to see whether or not such differences were stable over time. 130 British children, aged 9 to 11, completed six sets of Likert-type rating scales, presented in four different ways varying the position of positive labels and numerical values. The results showed, both initially and 8-12 weeks later, that presenting a positive label or a high score on the left of a scale led to significantly higher mean scores than did the other variations. These findings indicate that different arrangements of rating scales can produce different results which has clear implications for the administration of scales with children

The Halo Shape and Evolution of Polar Disc Galaxies

We examine the properties and evolution of a simulated polar disc galaxy. This galaxy is comprised of two orthogonal discs, one of which contains old stars (old stellar disc), and the other, containing both younger stars and the cold gas (polar disc) of the galaxy. By exploring the shape of the inner region of the dark matter halo, we are able to confirm that the halo shape is a oblate ellipsoid flattened in the direction of the polar disc. We also note that there is a twist in the shape profile, where the innermost 3 kpc of the halo flattens in the direction perpendicular to the old disc, and then aligns with the polar disc out until the virial radius. This result is then compared to the halo shape inferred from the circular velocities of the two discs. We also use the temporal information of the simulation to track the system's evolution, and identify the processes which give rise to this unusual galaxy type. We confirm the proposal that the polar disc galaxy is the result of the last major merger, where the angular moment of the interaction is orthogonal to the angle of the infalling gas. This merger is followed by the resumption of coherent gas infall. We emphasise that the disc is rapidly restored after the major merger and that after this event the galaxy begins to tilt. A significant proportion of the infalling gas comes from filaments. This infalling gas from the filament gives the gas its angular momentum, and, in the case of the polar disc galaxy, the direction of the gas filament does not change before or after the last major merger.Comment: Accepted for publication in MNRAS; 14 pages; 14 figure

A Large, Uniform Sample of X-ray Emitting AGN from the ROSAT All-Sky and Sloan Digital Sky Surveys: the Data Release 5 Sample

We describe further results of a program aimed to yield ~10^4 fully characterized optical identifications of ROSAT X-ray sources. Our program employs X-ray data from the ROSAT All-Sky Survey (RASS), and both optical imaging and spectroscopic data from the Sloan Digital Sky Survey (SDSS). RASS/SDSS data from 5740 deg^2 of sky spectroscopically covered in SDSS Data Release 5 (DR5) provide an expanded catalog of 7000 confirmed quasars and other AGN that are probable RASS identifications. Again in our expanded catalog, the identifications as X-ray sources are statistically secure, with only a few percent of the SDSS AGN likely to be randomly superposed on unrelated RASS X-ray sources. Most identifications continue to be quasars and Seyfert 1s with 15<m<21 and 0.01<z<4; but the total sample size has grown to include very substantial numbers of even quite rare AGN, e.g., now including several hundreds of candidate X-ray emitting BL Lacs and narrow-line Seyfert 1 galaxies. In addition to exploring rare subpopulations, such a large total sample may be useful when considering correlations between the X-ray and the optical, and may also serve as a resource list from which to select the "best" object (e.g., X-ray brightest AGN of a certain subclass, at a preferred redshift or luminosity) for follow-on X-ray spectral or alternate detailed studies.Comment: Accepted for publication in AJ; 32 pages, including 11 figures, and 6 example table

Electronic and paper versions of a faces pain intensity scale: concordance and preference in hospitalized children

<p>Abstract</p> <p>Background</p> <p>Assessment of pain in children is an important aspect of pain management and can be performed by observational methods or by self-assessment. The Faces Pain Scale-Revised (FPS-R) is a self-report tool which has strong positive correlations with other well established self-report pain intensity measures. It has been recommended for measuring pain intensity in school-aged children (4 years and older). The objective of this study is to compare the concordance and the preference for two versions, electronic and paper, of the FPS-R, and to determine whether an electronic version of the FPS-R can be used by children aged 4 and older.</p> <p>Methods</p> <p>The study is an observational, multicenter, randomized, cross-over, controlled, open trial. Medical and surgical patients in two pediatric hospitals (N = 202, age 4-12 years, mean age 8.3 years, 58% male) provided self-reports of their present pain using the FPS-R on a personal digital assistant (PDA) and on a paper version. Paper and electronic versions of the FPS-R were administered by a nurse in a randomized order: half the patients were given the PDA version first and the other half the paper version first. The time between the administrations was planned to be less than 30 minutes but not simultaneous. Two hundred and thirty-seven patients were enrolled; 35 were excluded from analysis because of misunderstanding of instructions or abnormal time between the two assessments.</p> <p>Results</p> <p>Final population for analysis comprised 202 children. The overall weighted Kappa was 0.846 (95%CI: 0.795; 0.896) and the Spearman correlation between scores on the two versions was r_s= 0.911 (p < 0.0001). The mean difference of pain scores was less than 0.1 out of 10, which was neither statistically nor clinically significant; 83.2% of children chose the same face on both versions of the FPS-R. Preference was not modified by order, sex, age, hospitalization unit (medical or surgical units), or previous analgesics. The PDA was preferred by 87.4% of the children who expressed a preference.</p> <p>Conclusion</p> <p>The electronic version of the FPS-R can be recommended for use with children aged 4 to 12, either in clinical trials or in hospitals to monitor pain intensity.</p

Lonely hearts and angry minds: Online dating rejection increases male (but not female) hostility

The present work explores the hostile tendencies elicited by romantic rejection in the increasingly common context of online dating. To empirically investigate this issue, we created an ad hoc online dating platform in which fictitious online dating partners romantically rejected heterosexual male and female participants. Results revealed that male-but not female-participants who were rejected by desired dating partners displayed increased hostility. This pattern of findings was consistent across different measures, which considered both aggressive tendencies against the rejecting partners and hostile attitudes against the opposite gender. Further, increased feelings of anger explained the relationship between online romantic rejection and increased male hostility. Our work and its findings have both theoretical and methodological implications for the understanding of interpersonal processes in online interactions and the growing body of literature on online dating

Two rapid assays for screening of patulin biodegradation

Artículo sobre distintos ensayos para comprobar la biodegradación de la patulinaThe mycotoxin patulin is produced by the blue mould pathogen Penicillium expansum in rotting apples during postharvest storage. Patulin is toxic to a wide range of organisms, including humans, animals, fungi and bacteria. Wash water from apple packing and processing houses often harbours patulin and fungal spores, which can contaminate the environment. Ubiquitous epiphytic yeasts, such as Rhodosporidium kratochvilovae strain LS11 which is a biocontrol agent of P. expansum in apples, have the capacity to resist the toxicity of patulin and to biodegrade it. Two non-toxic products are formed. One is desoxypatulinic acid. The aim of the work was to develop rapid, high-throughput bioassays for monitoring patulin degradation in multiple samples. Escherichia coli was highly sensitive to patulin, but insensitive to desoxypatulinic acid. This was utilized to develop a detection test for patulin, replacing time-consuming thin layer chromatography or high-performance liquid chromatography. Two assays for patulin degradation were developed, one in liquid medium and the other in semi-solid medium. Both assays allow the contemporary screening of a large number of samples. The liquid medium assay utilizes 96-well microtiter plates and was optimized for using a minimum of patulin. The semisolid medium assay has the added advantage of slowing down the biodegradation, which allows the study and isolation of transient degradation products. The two assays are complementary and have several areas of utilization, from screening a bank of microorganisms for biodegradation ability to the study of biodegradation pathways