University of Alabama

About: University of Alabama is a education organization based out in Tuscaloosa, Alabama, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 27323 authors who have published 48609 publications receiving 1565337 citations. The organization is also known as: Alabama & Bama.

The fifteenth data release of the Sloan Digital Sky Surveys: First release of MaNGA-derived quantities, data visualization tools, and stellar library

Abstract: Twenty years have passed since first light for the Sloan Digital Sky Survey (SDSS). Here, we release data taken by the fourth phase of SDSS (SDSS-IV) across its first three years of operation (2014 July–2017 July). This is the third data release for SDSS-IV, and the 15th from SDSS (Data Release Fifteen; DR15). New data come from MaNGA—we release 4824 data cubes, as well as the first stellar spectra in the MaNGA Stellar Library (MaStar), the first set of survey-supported analysis products (e.g., stellar and gas kinematics, emission-line and other maps) from the MaNGA Data Analysis Pipeline, and a new data visualization and access tool we call "Marvin." The next data release, DR16, will include new data from both APOGEE-2 and eBOSS; those surveys release no new data here, but we document updates and corrections to their data processing pipelines. The release is cumulative; it also includes the most recent reductions and calibrations of all data taken by SDSS since first light. In this paper, we describe the location and format of the data and tools and cite technical references describing how it was obtained and processed. The SDSS website (www.sdss.org) has also been updated, providing links to data downloads, tutorials, and examples of data use. Although SDSS-IV will continue to collect astronomical data until 2020, and will be followed by SDSS-V (2020–2025), we end this paper by describing plans to ensure the sustainability of the SDSS data archive for many years beyond the collection of data.

Perceiving vowels in a second language

Abstract: This study examines the perception of English vowels by native speakers of Italian. In two preliminary experiments, Italian university students who had lived in Canada for 3 months were found to have difficulty discriminating because they often identified both members of each contrast as instances of a single Italian vowel. The participants in two other experiments, long-time residents of Canada, were assigned to groups based on their age of arrival in Canada from Italy (early vs. late) and percentage of first language (L1) use (high L1 use vs. low L1 use). Experiment 3 focused on the discrimination of , and experiment 4 examined the discrimination of correct from incorrect realizations of . In both experiments, the early learners obtained higher discrimination scores than the late learners, and low-L1-use participants obtained higher scores than high-L1-use participants. Most important, the early learners who used Italian often (early high), but not the early learners who used Italian seldom (early low), were found to differ from native speakers of English in perceiving English vowels. These results suggest two important conclusions regarding second language (L2) perceptual learning: Learning an L2 in childhood does not guarantee a nativelike perception of L2 vowels, nor does the establishment of a sound system for the L1 preclude a functionally nativelike perception of L2 vowels. Another important finding is that, although the late learners generally perceived English vowels less accurately than the early learners, some perceived them accurately.This study was supported by grant DC00257 from the National Institute of Deafness and Other Communicative Disorders. The authors thank J. Prosperine and M. Pearse for help locating participants, Fr. M. Brodeur of St. Anthony's Church in Ottawa, Ontario, and all the participants. The authors are grateful to D. Meador and T. Piske for help preparing the stimuli used in experiment 4. Finally, thanks are extended to K. Aoyama, S. Imai, K. Tsukada, T. Piske, and three anonymous SSLA reviewers for comments on an earlier version of this article.

Social Media, Network Heterogeneity, and Opinion Polarization

Abstract: Employing a national probability survey in 2012, this study tests relationships between social media, social network service (SNS) network heterogeneity, and opinion polarization. The results show that the use of social media is a positive predictor of the level of network heterogeneity on SNSs and that the relationship is mediated by several news-related activities, such as getting news, news posting, and talking about politics on SNSs. Testing the association between SNS network heterogeneity and polarization, this study considers 3 different dimensions of opinion polarization: partisan, ideological, and issue. The findings indicate that political discussion moderates the relationship between network heterogeneity and the level of partisan and ideological polarizations. The implications of this study are discussed.