The Development of Instruments for Assessment of Instructional Practices in Standards-Based Teaching

We provide a description and rationale for the development of two instruments: 1) a classroom observation protocol; and, 2) a teacher interview protocol—designed to document the impact of reform-based professional development with undergraduate mathematics and science faculty, and its impact on the resultant preparation of teachers. Constructed upon review of the research on teaching and standards documents in mathematics and science, these instruments form the basis for data collection in a three-year longitudinal study of teaching practice among early career teachers as well as undergraduate college faculty. In addition, we suggest further applications of the observation protocol beyond the original purpose of our research study

Student perceptions of their autonomy at University

© 2017, The Author(s). Learner autonomy is a primary learning outcome of Higher Education in many countries. However, empirical evaluation of how student autonomy progresses during undergraduate degrees is limited. We surveyed a total of 636 students’ self-perceived autonomy during a period of two academic years using the Autonomous Learning Scale. Our analysis suggests that students do not perceive themselves as being any more autonomous as they progress through University. Given the relativity of self-perception metrics, we suggest that our results evince a “red queen” effect. In essence, as course expectations increase with each year, each student’s self-perceived autonomy relative to their ideal remains constant; we term this the “moving goalpost” hypothesis. This article corroborates pedagogical literature suggesting that providing students with opportunities to act autonomously and develop confidence is key to developing graduates who have the independence that they need in order to be successful in the workplace

Colour change and assortment in the western rainbowfish

Grouping behaviour is widespread across the animal kingdom, and is known to reduce an individual's risk of predation, for example through predator confusion. Theory predicts that individuals that are different in appearance to the rest of the group are at a greater risk of predation because they are more conspicuous to predators (the ‘oddity’ effect). Thus, animals should choose group mates that are the most similar in appearance to themselves. Another common antipredator tactic is crypsis (camouflage). Fishes are capable of changing colour to match their visual background, but few studies have examined how this might influence shoaling decisions, particularly in the context of the oddity effect. We induced colour pattern changes in a colourful species of freshwater fish, the western rainbowfish, Melanotaenia australis, by maintaining fish in dark and pale aquaria for 2 weeks. Analysis of the proportion of black body pigmentation confirmed that rainbowfish in dark environments developed darker colour patterns than those held in pale environments. We then conducted behavioural observations to determine whether fish subsequently based their shoaling decisions on body coloration. We found that rainbowfish preferred to shoal with similar individuals; fish that had been held in dark aquaria preferred to shoal with other dark fish and fish from pale aquaria preferred other pale fish. Our findings are consistent with the predictions of the oddity effect and demonstrate how morphological colour pattern changes and behavioural decisions interact to mediate antipredator tactics in fish

Conflict between background matching and social signalling in a colour-changing freshwater fish

The ability to change coloration allows animals to modify their patterning to suit a specific function. Many freshwater fishes, for example, can appear cryptic by altering the dispersion of melanin pigment in the skin to match the visual background. However, melanin-based pigments are also used to signal dominance among competing males; thus colour change for background matching may conflict with colour change for social status signalling. We used a colour-changing freshwater fish to investigate whether colour change for background matching influenced aggressive interactions between rival males. Subordinate males that had recently darkened their skin for background matching received heightened aggression from dominant males, relative to males whose coloration had not changed. We then determined whether the social status of a rival male, the focal male's previous social status, and his previous skin coloration, affected a male's ability to change colour for background matching. Social status influenced skin darkening in the first social encounter, with dominant males darkening more than subordinate males, but there was no effect of social status on colour change in the second social encounter. We also found that the extent of skin colour change (by both dominant and subordinate males) was dependent on previous skin coloration, with dark males displaying a smaller change in coloration than pale males. Our findings suggest that skin darkening for background matching imposes a significant social cost on subordinate males in terms of increased aggression. We also suggest that the use of melanin-based signals during social encounters can impede subsequent changes in skin coloration for other functions, such as skin darkening for background matching

The effects of speaking rate alternation on nasalance scores of individuals with hearing impairments

Includes bibliographical references.The purpose of the following study was to investigate the effects of changes of rate on the degree of nasalance in speakers with normal hearing and speakers with impaired hearing. Specifically, the following questions were asked: 1. Are speakers with impaired hearing able to manipulate rate in a fashion consistent with speakers with normal hearing? 2. Does nasalance, as measured using nasometry, increase with an increase in rate in speakers with normal hearing and speakers with impaired hearing? The study consisted often English speaking subjects, five with normal hearing and five with hearing impairments. All subjects were assessed using the Kay Model 6200 Nasometer to measure nasalance. Subjects were asked to say the sentence, "We were away a year ago" at five different speech rates: fastest, fast, normal, slow, and slowest. Three repetitions were performed at each of the speech rates. After each reading of a single sentence, the cursors from the nasometry analysis software were adjusted to highlight the beginning and end of the speech display to calculate the data obtained. Results from the study revealed as rate of speech decreased the amount of nasalance increased in normal hearing subjects. However, no correlation was found in the hearing impaired subjects in the relationship between rate and nasalance. Based on the conclusions of the study, it suggests that decreasing speaking rate to improve nasalance might not be a beneficial therapy technique. Further study of rate and nasalance is necessary to fully understand the conclusions of an uncorrelated relationship found in the present study.B.S. (Bachelor of Science

Handedness in fiddler crab fights

Asymmetric weapons are common in bilateral animals and, in some species, they can occur on either the left- or the right-hand side of the body (lateralization). Fiddler crabs (Uca spp, Decapoda: Ocypodidae) have an enlarged claw that is used in male–male combat over territories and in courtship displays. Males can be either right- or left-handed, and most species have a 1:1 ratio. Past studies have found little effect of handedness on fighting success, fight duration or other measures of combat. Here we show that, while handedness per se, does not affect fighting, handedness matching has a significant effect. In Uca mjoebergi, fights between different-handed males were more likely to escalate to grappling, suggesting that it is harder for the combatants to determine the winner. We suggest that the positioning of the claws during fighting creates distinct forces that result in different outcomes for same- versus different-handed fights. This can represent a strong selective pressure in populations with an uneven handedness distribution where the handedness minority will often engage in different-handed fights. We discuss these results in light of the selective forces that may act on handedness distribution in fiddler crabs

Serendipitous Discovery of An Infrared Bow Shock Near PSR J1549-4848 with Spitzer

We report on the discovery of an infrared cometary nebula around PSR J1549$-$4848 in our Spitzer survey of a few middle-aged radio pulsars. Following the discovery, multi-wavelength imaging and spectroscopic observations of the nebula were carried out. We detected the nebula in Spitzer IRAC 8.0, MIPS 24 and 70 $\mu$m imaging and in Spitzer IRS 7.5--14.4 $\mu$m spectroscopic observations, and also in the WISE all-sky survey at 12 and 22 $\mu$m.These data were analyzed in detail, and we find that the nebula can be described with a standard bow-shock shape, and that its spectrum contains polycyclic aromatic hydrocarbon and H$_2$ emission features. However, it is not certain which object drives the nebula. We analyze the field stars and conclude that none of them can be the associated object because stars with a strong wind or mass ejection that usually produce bow shocks are much brighter than the field stars. The pulsar is approximately 15\arcsec\ away from the region in which the associated object is expected to be located. In order to resolve the discrepancy, we suggest that a highly collimated wind could be emitted from the pulsar and produce the bow shock. X-ray imaging to detect the interaction of the wind with the ambient medium and high-spatial resolution radio imaging to determine the proper motion of the pulsar should be carried out, which will help verify the association of the pulsar with the bow shock nebula.Comment: 9 pages, 5 figures, accepted for publication in Ap

Comparative genomics approaches accurately predict deleterious variants in plants

Recent advances in genome resequencing have led to increased interest in prediction of the functional consequences of genetic variants. Variants at phylogenetically conserved sites are of particular interest, because they are more likely than variants at phylogenetically variable sites to have deleterious effects on fitness and contribute to phenotypic variation. Numerous comparative genomic approaches have been developed to predict deleterious variants, but the approaches are nearly always assessed based on their ability to identify known disease-causing mutations in humans. Determining the accuracy of deleterious variant predictions in nonhuman species is important to understanding evolution, domestication, and potentially to improving crop quality and yield. To examine our ability to predict deleterious variants in plants we generated a curated database of 2,910 Arabidopsis thaliana mutants with known phenotypes. We evaluated seven approaches and found that while all performed well, their relative ranking differed from prior benchmarks in humans. We conclude that deleterious mutations can be reliably predicted in A. thaliana and likely other plant species, but that the relative performance of various approaches does not necessarily translate from one species to another

Identification of red supergiants in nearby galaxies with mid-IR photometry

The role of episodic mass loss in massive star evolution is one of the most important open questions of current stellar evolution theory. Episodic mass loss produces dust and therefore causes evolved massive stars to be very luminous in the mid-infrared and dim at optical wavelengths. We aim to increase the number of investigated luminous mid-IR sources to shed light on the late stages of these objects. To achieve this we employed mid-IR selection criteria to identity dusty evolved massive stars in two nearby galaxies. The method is based on mid-IR colors, using 3.6 {\mu}m and 4.5 {\mu}m photometry from archival Spitzer Space Telescope images of nearby galaxies and J-band photometry from 2MASS. We applied our criteria to two nearby star-forming dwarf irregular galaxies, Sextans A and IC 1613, selecting eight targets, which we followed up with spectroscopy. Our spectral classification and analysis yielded the discovery of two M-type supergiants in IC 1613, three K-type supergiants and one candidate F-type giant in Sextans A, and two foreground M giants. We show that the proposed criteria provide an independent way for identifying dusty evolved massive stars, that can be extended to all nearby galaxies with available Spitzer/IRAC images at 3.6 {\mu}m and 4.5 {\mu}m.Comment: 8 pages, 4 figures, A&A in pres

Predictive validity of the CriSTAL tool for short-term mortality in older people presenting at Emergency Departments: a prospective study

© 2018, The Author(s). Abstract: To determine the validity of the Australian clinical prediction tool Criteria for Screening and Triaging to Appropriate aLternative care (CRISTAL) based on objective clinical criteria to accurately identify risk of death within 3 months of admission among older patients. Methods: Prospective study of ≥ 65 year-olds presenting at emergency departments in five Australian (Aus) and four Danish (DK) hospitals. Logistic regression analysis was used to model factors for death prediction; Sensitivity, specificity, area under the ROC curve and calibration with bootstrapping techniques were used to describe predictive accuracy. Results: 2493 patients, with median age 78–80 years (DK–Aus). The deceased had significantly higher mean CriSTAL with Australian mean of 8.1 (95% CI 7.7–8.6 vs. 5.8 95% CI 5.6–5.9) and Danish mean 7.1 (95% CI 6.6–7.5 vs. 5.5 95% CI 5.4–5.6). The model with Fried Frailty score was optimal for the Australian cohort but prediction with the Clinical Frailty Scale (CFS) was also good (AUROC 0.825 and 0.81, respectively). Values for the Danish cohort were AUROC 0.764 with Fried and 0.794 using CFS. The most significant independent predictors of short-term death in both cohorts were advanced malignancy, frailty, male gender and advanced age. CriSTAL’s accuracy was only modest for in-hospital death prediction in either setting. Conclusions: The modified CriSTAL tool (with CFS instead of Fried’s frailty instrument) has good discriminant power to improve prognostic certainty of short-term mortality for ED physicians in both health systems. This shows promise in enhancing clinician’s confidence in initiating earlier end-of-life discussions