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This case examines the complex partnership between the university teacher education program and the host school district. Many factors contribute to the expectations and requirements of both institutions, which can at times, conflict in fundamental ways. The theoretical and research-based methods of early childhood coursework are often different than the reality of those classrooms. Furthermore, the adoption of initiatives like, Culturally Responsive Teaching and Leading standards by university teacher education programs must translate to the fieldwork. School and district-wide mandates often overrule best pedagogical and developmentally appropriate practices. With these opposing perspectives how can supervisors bridge the gap between the university classroom and the primary classroom? How can supervisors support teacher candidates and mentor teachers in negotiating rigid curricular programming, and maintain professional partnerships?

The purpose of this study was to investigate the longitudinal prevalence of relative age effects (RAEs) across playing levels and positions in Northern Ireland international male soccer. Birthdates of U17 (n = 276), U19 (n = 320), U21 (n = 331), and senior (n = 108) international players between 2011 and 2023 were recorded. Chi-square tests and odds ratios with 95% confidence intervals were used to compare observed and expected birthdate distributions. A selection bias toward relatively older players was evident at U17 and U19 playing levels as well as defensive and midfield positions. In contrast, more relatively younger senior and forward players were selected. Longitudinal analyses revealed that of those players who were initially selected at U17, more relatively older players were re-selected at subsequent playing levels, but there were no birthdate asymmetries amongst new players added after U17. The results of this study demonstrate RAEs are prevalent across Northern Ireland international male soccer and are influenced by playing level as well as position. These findings have important implications for policy makers and practitioners as relatively older players are overrepresented at youth but not senior level, which questions the efficacy of this (un)conscious bias in the talent pathway.

Supportive early relationships are critical to young children's development. Previous research has focused primarily on aspects of specific parenting practices that impact infants' and toddlers' development. However, additional research is needed for a more nuanced understanding of the relationships among family experiences, parenting behaviors, and infants' and toddlers' social-emotional outcomes. To further explore these relationships among families experiencing economic risk, we conducted a secondary data analysis using a low-income Early Head Start sample. Our sample (n = 153) consisted of mother-child dyads who were racially and ethnically diverse (46% Hispanic; 27% Black, non-Hispanic; 14% White; approximately 10% identified as another race/ethnicity). About half (51%) of the children in our sample were male and children were, on average, 21 months old. Our results suggest that certain family experiences, including parenting stress and income, were negatively associated with the social-emotional outcomes of infants and toddlers. Parent education was positively associated with parenting behaviors. Additionally, maternal sensitivity was positively associated with infants' and toddlers' social-emotional competence. However, parent engagement and parent sensitivity did not mediate the relationship between family experiences and infants' and toddlers' social-emotional development.

Higher education institutions provide critical opportunities for students to acquire the skills necessary to enter the STEM workforce and serve as vital partners in the STEM educational-occupational pipeline. It is important that colleges and universities ensure that all undergraduates interested in STEM professions have the opportunity to see themselves as potential STEM candidates. However, a perception exists that STEM is not open to all students interested in STEM domains. In particular, undergraduates may be under the impression that entrance into STEM pathways is contingent on fixed intelligence or innate brilliance in order to succeed at the postsecondary level. Due to these perceptions, first-year students may prematurely exclude themselves from STEM participation due to a misalignment between their self-perceptions and the attributes they believe are required for STEM attainment. The purpose of this research was to investigate whether relationships existed among students' concepts of innate intelligence and disciplinary brilliance and students' self-perceptions of their ability and interest to major in STEM. First-year students' perceptions from a predominately non-STEM sample were measured and compared across four STEM domains: Life Sciences (biology/chemistry), Physical Sciences (math/physics), Applied Physical Sciences (computer science/engineering), and Health Sciences (premed/medical sciences). Comparative single-group structural equation models are presented, in addition to findings of whether students' gender identity influenced their overall perceptions of STEM undergraduate pathways.

Consistent evidence points to the importance of the early childhood home environment for children's concurrent and subsequent development. Yet little is known about the long-term association between parental warmth in early childhood and children's social-emotional well-being in late childhood for children with and without disabilities. To explore these long-term relationships, we conducted a study using data from the Early Head Start Research and Evaluation project. Our results suggest that parental warmth in early childhood is associated with children's, but not teachers', reports of child social-emotional well-being in fifth grade. Additionally, greater levels of parental warmth in early childhood were negatively associated with parent-reported internalizing and externalizing behavior in fifth grade for children with disabilities. Our results indicate that targeted parenting programs through early childhood programs and early intervention services may be an important resource for families with young children with disabilities.

The nature and role of the binary companion of carbon–oxygen white dwarf stars that explode as Type Ia supernovae (SNe Ia) are not yet fully understood. Past detections of circumstellar material (CSM) that contain hydrogen for a small number of SN Ia progenitor systems suggest that at least some have a nondegenerate companion. In order to constrain the prevalence, location, and quantity of CSM in SN Ia systems, we performed a near-ultraviolet (NUV) survey with the Hubble Space Telescope (HST) to look for the high-energy signature of SN Ia ejecta interacting with the CSM. Our survey revealed that SN 2015cp, an SN 1991T-like overluminous SN Ia, was experiencing late-onset interaction between its ejecta and the surrounding CSM 664 days after its light-curve peak. We present ground- and space-based follow-up observations of SN 2015cp that reveal optical emission lines of H and Ca, typical signatures of ejecta–CSM interaction. We show how SN 2015cp was likely similar to the well-studied SN Ia–CSM event PTF11kx, making it the second case in which an unambiguously classified SN Ia was observed to interact with a distant shell of CSM that contains hydrogen (RCSM ≳ 1016 cm). The remainder of our HST NUV images of SNe Ia were nondetections that we use to constrain the occurrence rate of observable late-onset CSM interaction. We apply theoretical models for the emission from ejecta–CSM interaction to our NUV nondetections and place upper limits on the mass and radial extent of CSM in SN Ia progenitor systems. [ABSTRACT FROM AUTHOR]

Despite their cosmological utility, the progenitors of Type Ia supernovae (SNe Ia) are still unknown, with many efforts focused on whether accretion from a nondegenerate companion can grow a carbon–oxygen white dwarf to near the Chandrasekhar mass. The association of SNe Ia resembling SN 1991T (“91T-like”) with circumstellar interaction may be evidence for this “single-degenerate” channel. However, the observed circumstellar medium (CSM) in these interacting systems is unlike a stellar wind—of particular interest, it is sometimes detached from the stellar surface, residing at ∼1016 cm. A Hubble Space Telescope (HST) program to discover detached CSM around 91T-like SNe Ia successfully discovered interaction nearly two years after explosion in SN 2015cp (Graham et al. 2018). In this work, we present radio and X-ray follow-up observations of SN 2015cp and analyze them in the framework of Harris et al. (2016) to limit the properties of a constant-density CSM shell in this system. Assuming the HST detection took place shortly after the shock crossed the CSM, we constrain the total CSM mass in this system to be <0.5 . This limit is comparable to the CSM mass of supernova PTF11kx, but does not rule out lower masses predicted for recurrent novae. From lessons learned modeling PTF11kx and SN 2015cp, we suggest a strategy for future observations of these events to increase the sample of known interacting SNe Ia. [ABSTRACT FROM AUTHOR]

The Wide Field InfraRed Survey Telescope (WFIRST) was the highest-ranked large space-based mission of the 2010 New Worlds, New Horizons decadal survey. It is now a NASA mission in formulation with a planned launch in the mid 2020s. A primary mission objective is to precisely constrain the nature of dark energy through multiple probes, including Type Ia supernovae (SN Ia). Here, we present the first realistic simulations of the WFIRST SN survey based on current hardware specifications and using open-source tools. We simulate SN light curves and spectra as viewed by the WFIRST wide-field channel (WFC) imager and integral field channel (IFC) spectrometer, respectively. We examine 11 survey strategies with different time allocations between the WFC and IFC, two of which are based upon the strategy described by the WFIRST Science Definition Team, which measures SN distances exclusively from IFC data. We propagate statistical and, crucially, systematic uncertainties to predict the Dark Energy Task Force figure of merit (FoM) for each strategy. Of the strategies investigated, we find the most successful to be WFC focused. However, further work in constraining systematics is required to fully optimize the use of the IFC. Even without improvements to other cosmological probes, the WFIRST SN survey has the potential to increase the FoM by more than an order of magnitude from the current values. Although the survey strategies presented here have not been fully optimized, these initial investigations are an important step in the development of the final hardware design and implementation of the WFIRST mission. [ABSTRACT FROM AUTHOR]

Realizing Refsdal’s original idea from 1964, we present estimates of the Hubble constant that are complementary to, and potentially competitive with, those of other cosmological probes. We use the observed positions of 89 multiple images, with extensive spectroscopic information, from 28 background sources and the measured time delays between the images S1–S4 and SX of supernova “Refsdal” (z = 1.489), which were obtained thanks to Hubble Space Telescope deep imaging and Multi Unit Spectroscopic Explorer data. We extend the strong-lensing modeling of the Hubble Frontier Fields galaxy cluster MACS J1149.5+2223 (z = 0.542), published by Grillo et al. (2016), and explore different ΛCDM models. Taking advantage of the lensing information associated to the presence of very close pairs of multiple images at various redshifts, and to the extended surface brightness distribution of the SN Refsdal host, we can reconstruct the total mass-density profile of the cluster very precisely. The combined dependence of the multiple-image positions and time delays on the cosmological parameters allows us to infer the values of H0 and Ωm with relative (1σ) statistical errors of, respectively, 6% (7%) and 31% (26%) in flat (general) cosmological models, assuming a conservative 3% uncertainty on the final time delay of image SX and, remarkably, no priors from other cosmological experiments. Our best estimate of H0, based on the model described in this work, will be presented when the final time-delay measurement becomes available. Our results show that it is possible to utilize time delays in lens galaxy clusters as an important alternative tool for measuring the expansion rate and the geometry of the universe. [ABSTRACT FROM AUTHOR]

Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as core-collapse supernovae (SNe). We focus on stripped-envelope SNe, whose progenitors have lost their outer hydrogen and possibly helium layers before explosion. We use these results to interpret new Hubble Space Telescope observations of the site of the broad-lined Type Ic SN 2002ap, 14 years post-explosion. For a subsolar metallicity consistent with SN 2002ap, we expect a main-sequence (MS) companion present in about two thirds of all stripped-envelope SNe and a compact companion (likely a stripped helium star or a white dwarf/neutron star/black hole) in about 5% of cases. About a quarter of progenitors are single at explosion (originating from initially single stars, mergers, or disrupted systems). All of the latter scenarios require a massive progenitor, inconsistent with earlier studies of SN 2002ap. Our new, deeper upper limits exclude the presence of an MS companion star >8–10 , ruling out about 40% of all stripped-envelope SN channels. The most likely scenario for SN 2002ap includes nonconservative binary interaction of a primary star initially . Although unlikely (<1% of the scenarios), we also discuss the possibility of an exotic reverse merger channel for broad-lined Type Ic events. Finally, we explore how our results depend on the metallicity and the model assumptions and discuss how additional searches for companions can constrain the physics that govern the evolution of SN progenitors. [ABSTRACT FROM AUTHOR]

We have acquired Hubble Space Telescope(HST) and Very Large Telescope near-infrared spectra and images of supernova (SN) Refsdal after its discovery as an Einstein cross in fall 2014. The HST light curve of SN Refsdal has a shape consistent with the distinctive, slowly rising light curves of SN 1987A-like SNe, and we find strong evidence for a broad Hα P-Cygni profile and Na I D absorption in the HST grism spectrum at the redshift (z = 1.49) of the spiral host galaxy. SNe IIn, largely powered by circumstellar interaction, could provide a good match to the light curve of SN Refsdal, but the spectrum of a SN IIn would not show broad and strong Hα and Na I D absorption. From the grism spectrum, we measure an Hα expansion velocity consistent with those of SN 1987A-like SNe at a similar phase. The luminosity, evolution, and Gaussian profile of the Hα emission of the WFC3 and X-shooter spectra, separated by ∼2.5 months in the rest frame, provide additional evidence that supports the SN 1987A-like classification. In comparison with other examples of SN 1987A-like SNe, photometry of SN Refsdal favors bluer B − V and V − R colors and one of the largest luminosities for the assumed range of potential magnifications. The evolution of the light curve at late times will provide additional evidence about the potential existence of any substantial circumstellar material. Using MOSFIRE and X-shooter spectra, we estimate a subsolar host-galaxy metallicity (8.3 ± 0.1 dex and <8.4 dex, respectively) near the explosion site. [ABSTRACT FROM AUTHOR]

We present the first year of Hubble Space Telescope imaging of the unique supernova (SN) “Refsdal,” a gravitationally lensed SN at z = 1.488 ± 0.001 with multiple images behind the galaxy cluster MACS J1149.6+2223. The first four observed images of SN Refsdal (images S1–S4) exhibited a slow rise (over ∼150 days) to reach a broad peak brightness around 2015 April 20. Using a set of light curve templates constructed from SN 1987A-like peculiar Type II SNe, we measure time delays for the four images relative to S1 of 4 ± 4 (for S2), 2 ± 5 (S3), and 24 ± 7 days (S4). The measured magnification ratios relative to S1 are 1.15 ± 0.05 (S2), 1.01 ± 0.04 (S3), and 0.34 ± 0.02 (S4). None of the template light curves fully captures the photometric behavior of SN Refsdal, so we also derive complementary measurements for these parameters using polynomials to represent the intrinsic light curve shape. These more flexible fits deliver fully consistent time delays of 7 ± 2 (S2), 0.6 ± 3 (S3), and 27 ± 8 days (S4). The lensing magnification ratios are similarly consistent, measured as 1.17 ± 0.02 (S2), 1.00 ± 0.01 (S3), and 0.38 ± 0.02 (S4). We compare these measurements against published predictions from lens models, and find that the majority of model predictions are in very good agreement with our measurements. Finally, we discuss avenues for future improvement of time delay measurements—both for SN Refsdal and for other strongly lensed SNe yet to come. [ABSTRACT FROM AUTHOR]

Supernova “Refsdal,” multiply imaged by cluster MACS1149.5+2223, represents a rare opportunity to make a true blind test of model predictions in extragalactic astronomy, on a timescale that is short compared to a human lifetime. In order to take advantage of this event, we produced seven gravitational lens models with five independent methods, based on Hubble Space Telescope (HST) Hubble Frontier Field images, along with extensive spectroscopic follow-up observations by HST, the Very Large and the Keck Telescopes. We compare the model predictions and show that they agree reasonably well with the measured time delays and magnification ratios between the known images, even though these quantities were not used as input. This agreement is encouraging, considering that the models only provide statistical uncertainties, and do not include additional sources of uncertainties such as structure along the line of sight, cosmology, and the mass sheet degeneracy. We then present the model predictions for the other appearances of supernova “Refsdal.” A future image will reach its peak in the first half of 2016, while another image appeared between 1994 and 2004. The past image would have been too faint to be detected in existing archival images. The future image should be approximately one-third as bright as the brightest known image (i.e., mag at peak and mag six months before peak), and thus detectable in single-orbit HST images. We will find out soon whether our predictions are correct. [ABSTRACT FROM AUTHOR]

We give an overview of the Grism Lens Amplified Survey from Space (GLASS), a large Hubble Space Telescope program aimed at obtaining grism spectroscopy of the fields of 10 massive clusters of galaxies at redshift z = 0.308–0.686, including the Hubble Frontier Fields (HFF). The Wide Field Camera 3 (WFC3) yields near-infrared spectra of the cluster cores covering the wavelength range 0.81–1.69 μm through grisms G102 and G141, while the Advanced Camera for Surveys in parallel mode provides G800L spectra of the infall regions of the clusters. The WFC3 spectra are taken at two almost orthogonal position angles in order to minimize the effects of confusion. After summarizing the scientific drivers of GLASS, we describe the sample selection as well as the observing strategy and data processing pipeline. We then utilize MACS J0717.5+3745, a HFF cluster and the first one observed by GLASS, to illustrate the data quality and the high-level data products. Each spectrum brighter than is visually inspected by at least two co-authors and a redshift is measured when sufficient information is present in the spectra. Furthermore, we conducted a thorough search for emission lines through all of the GLASS WFC3 spectra with the aim of measuring redshifts for sources with continuum fainter than We provide a catalog of 139 emission-line-based spectroscopic redshifts for extragalactic sources, including three new redshifts of multiple image systems (one probable, two tentative). In addition to the data itself, we also release software tools that are helpful to navigate the data. [ABSTRACT FROM AUTHOR]

We present a time series of the highest resolution spectra yet published for the nearby Type Ia supernova (SN Ia) 2014J in M82. They were obtained at 11 epochs over 33 days around peak brightness with the Levy Spectrograph (resolution R ≈ 110,000) on the 2.4 m Automated Planet Finder telescope at Lick Observatory. We identify multiple Na i D and K i absorption features as well as absorption by Ca ii H&K and several of the more common diffuse interstellar bands (DIBs). We see no evolution in any component of Na i D, Ca ii, or in the DIBs, but do establish the dissipation/weakening of the two most blueshifted components of K i. We present several potential physical explanations, finding the most plausible to be photoionization of circumstellar material, and discuss the implications of our results with respect to the progenitor scenario of SN 2014J. [ABSTRACT FROM AUTHOR]