An analysis of first grade reading workbooks

Thesis (M.A.)--Boston University, 1948. This item was digitized by the Internet Archive

An analysis of first grade reading workbooks

Thesis (M.A.)--Boston University, 1948. This item was digitized by the Internet Archive

Want to Hookup?: Sex Differences in Short Term Mate Attraction Tactics

While a great deal of psychological research has been conducted on sex-specific mate choice preferences, relatively little attention has been directed toward how heterosexual men and women solicit short-term sexual partners, and which acts are perceived to be the most effective. The present research relied on an act nomination methodology with the goal of determining which actions are used by men and women to solicit a short-term “hook-up” partner (study 1) and then determine which of these actions are perceived as most effective by men and women (study 2). Using sexual strategy theory, we hypothesized that actions that suggest sexual access would be nominated most often by women whereas actions that suggest a willingness to commit were expected to be nominated most often by men. Additionally, men and women were predicted to rate actions by men that suggest a willingness to commit as most effective and actions by women that suggest sexual access as most effective. The results were consistent with these hypotheses. These findings are discussed in the context of both short- and long-term mating strategies and mate solicitation. The relationship between motivation, sexual strategies, and sexual behavior are examined, along with the need for research on the hookup tactics and motivations of self-identifying gay, lesbian, and bisexual individuals

RELICS: Strong Lens Models for Five Galaxy Clusters From the Reionization Lensing Cluster Survey

Strong gravitational lensing by galaxy clusters magnifies background galaxies, enhancing our ability to discover statistically significant samples of galaxies at z>6, in order to constrain the high-redshift galaxy luminosity functions. Here, we present the first five lens models out of the Reionization Lensing Cluster Survey (RELICS) Hubble Treasury Program, based on new HST WFC3/IR and ACS imaging of the clusters RXC J0142.9+4438, Abell 2537, Abell 2163, RXC J2211.7-0349, and ACT-CLJ0102-49151. The derived lensing magnification is essential for estimating the intrinsic properties of high-redshift galaxy candidates, and properly accounting for the survey volume. We report on new spectroscopic redshifts of multiply imaged lensed galaxies behind these clusters, which are used as constraints, and detail our strategy to reduce systematic uncertainties due to lack of spectroscopic information. In addition, we quantify the uncertainty on the lensing magnification due to statistical and systematic errors related to the lens modeling process, and find that in all but one cluster, the magnification is constrained to better than 20% in at least 80% of the field of view, including statistical and systematic uncertainties. The five clusters presented in this paper span the range of masses and redshifts of the clusters in the RELICS program. We find that they exhibit similar strong lensing efficiencies to the clusters targeted by the Hubble Frontier Fields within the WFC3/IR field of view. Outputs of the lens models are made available to the community through the Mikulski Archive for Space TelescopesComment: Accepted to Ap

RELICS: High-Resolution Constraints on the Inner Mass Distribution of the z=0.83 Merging Cluster RXJ0152.7-1357 from strong lensing

Strong gravitational lensing (SL) is a powerful means to map the distribution of dark matter. In this work, we perform a SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (z=0.83, also known as CL 0152.7-1357) in \textit{Hubble Space Telescope} images, taken in the framework of the Reionization Lensing Cluster Survey (RELICS). On top of a previously known $z=3.93$ galaxy multiply imaged by RXJ0152.7-1357, for which we identify an additional multiple image, guided by a light-traces-mass approach we identify seven new sets of multiply imaged background sources lensed by this cluster, spanning the redshift range [1.79-3.93]. A total of 25 multiple images are seen over a small area of ~0.4 $arcmin^2$, allowing us to put relatively high-resolution constraints on the inner matter distribution. Although modestly massive, the high degree of substructure together with its very elongated shape make RXJ0152.7-1357 a very efficient lens for its size. This cluster also comprises the third-largest sample of z~6-7 candidates in the RELICS survey. Finally, we present a comparison of our resulting mass distribution and magnification estimates with those from a Lenstool model. These models are made publicly available through the MAST archive.Comment: 15 Pages, 7 Figures, 4 Tables Accepted for publication in Ap

RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z=0.972 Cluster

We present a lens model for the cluster SPT-CLJ0615$-$5746, which is the highest redshift ($z=0.972$) system in the Reionization of Lensing Clusters Survey (RELICS), making it the highest redshift cluster for which a full strong lens model is published. We identify three systems of multiply-imaged lensed galaxies, two of which we spectroscopically confirm at $z=1.358$ and $z=4.013$, which we use as constraints for the model. We find a foreground structure at $z\sim0.4$, which we include as a second cluster-sized halo in one of our models; however two different statistical tests find the best-fit model consists of one cluster-sized halo combined with three individually optimized galaxy-sized halos, as well as contributions from the cluster galaxies themselves. We find the total projected mass density within $r=26.7"$ (the region where the strong lensing constraints exist) to be $M=2.51^{+0.15}_{-0.09}\times 10^{14}$~M$_{\odot}$. If we extrapolate out to $r_{500}$, our projected mass density is consistent with the mass inferred from weak lensing and from the Sunyaev-Zel'dovich effect ($M\sim10^{15}$~M$_{\odot}$). This cluster is lensing a previously reported $z\sim10$ galaxy, which, if spectroscopically confirmed, will be the highest-redshift strongly lensed galaxy known.Comment: 15 pages, 8 figures 4 tables. ApJ Accepte

RELICS: A Very Large (θE∼40"\theta_{E}\sim40") Cluster Lens -- RXC J0032.1+1808

Extensive surveys with the \textit{Hubble Space Telescope} (HST) over the past decade, targeting some of the most massive clusters in the sky, have uncovered dozens of galaxy-cluster strong lenses. The massive cluster strong-lens scale is typically \theta_{E}\sim10\arcsec to \sim30-35\arcsec, with only a handful of clusters known with Einstein radii \theta_{E}\sim40\arcsec or above (for $z_{source}=2$, nominally). Here we report another very large cluster lens, RXC J0032.1+1808 ($z=0.3956$), the second richest cluster in the redMapper cluster catalog and the 85th most massive cluster in the Planck Sunyaev-Zel'dovich catalog. With our Light-Traces-Mass and fully parametric (dPIEeNFW) approaches, we construct strong lensing models based on 18 multiple images of 5 background galaxies newly identified in the \textit{Hubble} data mainly from the \textit{Reionization Lensing Cluster Survey} (RELICS), in addition to a known sextuply imaged system in this cluster. Furthermore, we compare these models to Lenstool and GLAFIC models that were produced independently as part of the RELICS program. All models reveal a large effective Einstein radius of \theta_{E}\simeq40\arcsec ($z_{source}=2$), owing to the obvious concentration of substructures near the cluster center. Although RXC J0032.1+1808 has a very large critical area and high lensing strength, only three magnified high-redshift candidates are found within the field targeted by RELICS. Nevertheless, we expect many more high-redshift candidates will be seen in wider and deeper observations with \textit{Hubble} or \emph{JWST}. Finally, the comparison between several algorithms demonstrates that the total error budget is largely dominated by systematic uncertainties.Comment: 23 pages, accepted for publication in Ap

RELICS: Strong Lensing analysis of the galaxy clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849

We present a strong-lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a Light-Traces-Mass technique to uncover sets of multiply images and constrain the mass distribution of the clusters. These mass models are the first published for Abell S295 and MACS J0159.8-0849, and are improvements over previous models for Abell 697 and MACS J0025.4-1222. Our analysis for MACS J0025.4-1222 and Abell S295 shows a bimodal mass distribution supporting the merger scenarios proposed for these clusters. The updated model for MACS J0025.4-1222 suggests a substantially smaller critical area than previously estimated. For MACS J0159.8-0849 and Abell 697 we find a single peak and relatively regular morphology, revealing fairly relaxed clusters. Despite being less prominent lenses, three of these clusters seem to have lensing strengths, i.e. cumulative area above certain magnification, similar to the Hubble Frontier Fields clusters (e.g., A($\mu>5$) $\sim 1-3$ arcmin$^2$, A($\mu>10$) $\sim 0.5-1.5$ arcmin$^2$), which in part can be attributed to their merging configurations. We make our lens models publicly available through the Mikulski Archive for Space Telescopes. Finally, using Gemini-N/GMOS spectroscopic observations we detect a single emission line from a high-redshift $J_{125}\simeq25.7$ galaxy candidate lensed by Abell 697. While we cannot rule out a lower-redshift solution, we interpret the line as Ly$\alpha$ at $z=5.800\pm 0.001$, in agreement with its photometric redshift and dropout nature. Within this scenario we measure a Ly$\alpha$ rest-frame equivalent width of $52\pm22$ \AA, and an observed Gaussian width of $117\pm 15$ km/s.Comment: 23 pages, 16 figures; V2, accepted for publication in Ap

Neighbourhood perceptions of physical activity: a qualitative study

Background: Effective promotion of physical activity in low income communities is essential given the high prevalence of inactivity in this sector. Methods: This study explored determinants of engaging in physical activity in two Irish city based neighbourhoods using a series of six focus groups and twenty five interviews with adult residents. Data were analysed using constant comparison methods with a grounded theory approach. Results: Study findings centred on the concept of 'community contentment'. Physical activity was related to the degree of contentment/comfort within the 'self' and how the 'self' interacts within the neighbourhood. Contemporary focus on outer bodily appearance and pressure to comply with societal expectations influenced participants' sense of confidence and competence. Social interaction, involvement, and provision of adequate social supports were viewed as positive and motivating. However normative expectations appeared to affect participants' ability to engage in physical activity, which may reflect the 'close knit' culture of the study neighbourhoods. Access to suitable local facilities and amenities such as structured and pleasant walking routes was regarded as essential. Indeed participants considered walking to be their preferred form of physical activity which may relate to the minimal skill requirement, ease of access and low financial costs incurred. Conclusion: In the context of physical activity, health promoters need to be conscious of the difficulties that individuals feel in relation to bodily appearance and the pressure to comply with societal standards. This may be particularly relevant in low income settings where insufficient allocation of resources and social supports means that individuals have less opportunity to attend to physical activity than individuals living in higher income settings