Integrated Stellar Populations: Confronting Photometry with Spectroscopy

We investigate the ability of spectroscopic techniques to yield realistic star formation histories (SFHs) for the bulges of spiral galaxies based on a comparison with their observed broadband colors. Full spectrum fitting to optical spectra indicates that recent (within ~1 Gyr) star formation activity can contribute significantly to the V-band flux, whilst accounting for only a minor fraction of the stellar mass budget which is made up primarily of old stars. Furthermore, recent implementations of stellar population (SP) models reveal that the inclusion of a more complete treatment of the thermally pulsating asymptotic giant branch (TP-AGB) phase to SP models greatly increases the NIR flux for SPs of ages 0.2-2 Gyr. Comparing the optical--NIR colors predicted from population synthesis fitting, using models which do not include all stages of the TP-AGB phase, to the observed colors reveals that observed optical--NIR colors are too red compared to the model predictions. However, when a 1 Gyr SP from models including a full treatment the TP-AGB phase is used, the observed and predicted colors are in good agreement. This has strong implications for the interpretation of stellar populations, dust content, and SFHs derived from colors alone.Comment: 6 pages, 6 figures, accepted for publication in the Astrophysical Journa

Mixed methods evaluation of an educational intervention to change mental health nurses' attitudes to people diagnosed with borderline personality disorder

Aims and objectives: To evaluate and explore mental health nurses’ responses to and experience of an educational intervention to improve attitudes towards people with a diagnosis of Borderline Personality Disorder. Report findings are concordant with relevant EQUATOR guidelines (STROBE and COREQ).Background: Attitudes towards people with a diagnosis of Borderline Personality Disorder are poorer than for people with other diagnoses. There is limited evidence about what might improve this situation. One intervention with reportedly good effect uses an underlying biosocial model of borderline personality disorder. No previous intervention has been co-produced with an expert-by-experience. We developed and delivered a 1-day intervention comprising these elements.Design: A mixed-methods design was used comprising prospective uncontrolled cohort intervention and qualitative elements. Participants were mental health nursing staff working in inpatient and community settings in one NHS Board in Scotland, UK.Methods: Measurement of cognitive and emotional attitudes to people with a borderline personality diagnosis at pre- and post- intervention (N =28) and at 4-month follow-up. Focus groups were used to explore participants’ experiences of the intervention (N =11).Results: Quantitative evaluation revealed some sustained changes consistent with expected attitudinal gains in relation to the perceived treatment characteristics of this group, the perception of their suicidal tendencies, and negative attitudes in general. Qualitative findings revealed some hostility towards the underpinning biosocial model and positive appreciation for the involvement of an expert-by-experience. Conclusions: Sustained benefits of an educational intervention for people working with people diagnosed with BPD in some but not all areas. Participants provided contrasting messages about what they think will be useful.Relevance to clinical practice: The study provides further evidence for incorporation of a biosocial model into staff training as well as the benefits of expert-by-experience co-production. Mental health nurses, however, believe that more well-resourced services are the key to improving care. <br/

Entropy, Ergodicity and Stem Cell Multipotency

Populations of mammalian stem cells commonly exhibit considerable cell-cell variability. However, the functional role of this diversity is unclear. Here, we analyze expression fluctuations of the stem cell surface marker Sca1 in mouse hematopoietic progenitor cells using a simple stochastic model and find that the observed dynamics naturally lie close to a critical state, thereby producing a diverse population that is able to respond rapidly to environmental changes. We propose an information-theoretic interpretation of these results that views cellular multipotency as an instance of maximum entropy statistical inference.Comment: 6 pages, 3 figure

Characterization of Selected Nineteenth-Century Southern Ontario Domestic Earthenwares by Chemical Analysis

The elemental analysis of the glaze from domestic earthenwares at four kilns, including that of the David Burns Pottery, has been carried out in an attempt to establish an identification scheme for each pottery. No clear-cut identification for each of the four groups was found, although it seems possible to distinguish between glazed pottery from the David Burns and the Streetsville kilns and between pottery from the New Hamburg and the Egmondville kilns, on the basis of specific elemental concentrations. Résumé L'article présente les résultats d'une analyse des composants de la glaçure de faïences provenant de quatre fours différents, dont celui de la David Burns Pottery. Cette analyse avait pour but d'établir une méthode d'identification pour chaque sorte de poterie. Les auteurs rapportent que les résultats ne permettent pas de délimiter avec précision chacun des quatre groupes, même s'il semble possible défaire des distinctions entre la poterie à glaçure provenant des fours de David Burns et de Streetsville et entre la poterie des fours de New Hamburg et d'Egmondville d'après la concentration particulière des composants

Thermal barriers constrain microbial elevational range size via climate variability

Range size is invariably limited and understanding range size variation is an important objective in ecology. However, microbial range size across geographical gradients remains understudied, especially on mountainsides. Here, the patterns of range size of stream microbes (i.e., bacteria and diatoms) and macroorganisms (i.e., macroinvertebrates) along elevational gradients in Asia and Europe were examined. In bacteria, elevational range size showed non-significant phylogenetic signals. In all taxa, there was a positive relationship between niche breadth and species elevational range size, driven by local environmental and climatic variables. No taxa followed the elevational Rapoport's rule. Climate variability explained the most variation in microbial mean elevational range size, whereas local environmental variables were more important for macroinvertebrates. Seasonal and annual climate variation showed negative effects, while daily climate variation had positive effects on community mean elevational range size for all taxa. The negative correlation between range size and species richness suggests that understanding the drivers of range is key for revealing the processes underlying diversity. The results advance the understanding of microbial species thermal barriers by revealing the importance of seasonal and diurnal climate variation, and highlight that aquatic and terrestrial biota may differ in their response to short- and long-term climate variability.Peer reviewe

Knots, Braids and Hedgehogs from the Eikonal Equation

The complex eikonal equation in the three space dimensions is considered. We show that apart from the recently found torus knots this equation can also generate other topological configurations with a non-trivial value of the $\pi_2(S^2)$ index: braided open strings as well as hedgehogs. In particular, cylindric strings i.e. string solutions located on a cylinder with a constant radius are found. Moreover, solutions describing strings lying on an arbitrary surface topologically equivalent to cylinder are presented. We discus them in the context of the eikonal knots. The physical importance of the results originates in the fact that the eikonal knots have been recently used to approximate the Faddeev-Niemi hopfions.Comment: 15 pages, 5 figure

Experimental demonstration of coupled optical springs

Optical rigidity will play an important role in improving the sensitivity of future generations of gravitational wave (GW) interferometers, which employ high laser power in order to reach and exceed the standard quantum limit. Several experiments have demonstrated the combined effect of two optical springs on a single system for very low-weight mirror masses or membranes. In this paper we investigate the complex interactions between multiple optical springs and the surrounding apparatus in a system of comparable dynamics to a large-scale GW detector. Using three 100 g mirrors to form a coupled cavity system capable of sustaining two or more optical springs, we demonstrate a number of different regimes of opto-mechanical rigidity and measurement techniques. Our measurements reveal couplings between each optical spring and the control loops that can affect both the achievable increase in sensitivity and the stability of the system. Hence this work establishes a better understanding of the realisation of these techniques and paves the way to their application in future GW observatories, such as upgrades to Advanced LIGO

Effective Chaperone Selection and Training for Enhanced Youth Experiences

This article identifies key strategies for selecting and training chaperones for youth programs. Although substantial research on volunteer core competencies and training exists, very little has been written to specifically address volunteers who serve in a chaperone capacity. We surveyed chaperones who had participated in an international youth development program to identify the most valuable personal characteristics of a successful chaperone and the most beneficial elements of a pre-event chaperone training program. The lists of these key characteristics and training topics can be used by Extension professionals in selecting chaperones and designing training opportunities for their own programs