Pennsylvania State University

About: Pennsylvania State University is a education organization based out in State College, Pennsylvania, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 79763 authors who have published 196876 publications receiving 8318601 citations. The organization is also known as: Penn State & PSU.

Codemeshing in Academic Writing: Identifying Teachable Strategies of Translanguaging

Abstract: Studies on translanguaging of multilingual students have turned their attention to teachable strategies in classrooms. This study is based on the assumption that it is possible to learn from students' translanguaging strategies while developing their proficiency through a dialogical pedagogy. Based on a classroom ethnography, this article describes the translanguaging strategies of a Saudi Arabian undergraduate student in her essay writing. Her strategies are classified through thematic coding of multiple forms of data: drafts of essay, journals, classroom assignments, peer review, stimulated recall, and member check. The strategies are of 4 types: recontextualization strategies, voice strategies, interactional strategies, and textualization strategies. The study describes how the feedback of the instructor and peers can help students question their choices, think critically about diverse options, assess the effectiveness of their choices, and develop metacognitive awareness. [ABSTRACT FROM AUTHOR]

Seeing Black: Race, Crime, and Visual Processing

Abstract: Using police officers and undergraduates as participants, the authors investigated the influence of stereotypic associations on visual processing in 5 studies. Study 1 demonstrates that Black faces influence participants' ability to spontaneously detect degraded images of crime-relevant objects. Conversely, Studies 2-4 demonstrate that activating abstract concepts (i.e., crime and basketball) induces attentional biases toward Black male faces. Moreover, these processing biases may be related to the degree to which a social group member is physically representative of the social group (Studies 4-5). These studies, taken together, suggest that some associations between social groups and concepts are bidirectional and operate as visual tuning devices--producing shifts in perception and attention of a sort likely to influence decision making and behavior.

The Chandra Deep Field North Survey. XIII. 2 Ms Point-Source Catalogs

Abstract: We present point-source catalogs for the ?2 Ms exposure of the Chandra Deep Field North, currently the deepest X-ray observation of the universe in the 0.5?8.0 keV band. Five hundred and three (503) X-ray sources are detected over an ?448 arcmin2 area in up to seven X-ray bands. Twenty (20) of these X-ray sources lie in the central ?5.3 arcmin2 Hubble Deep Field North (13,600 sources deg-2). The on-axis sensitivity limits are ?2.5 ? 10-17 ergs cm-2 s-1 (0.5?2.0 keV) and ?1.4 ? 10-16 ergs cm-2 s-1 (2?8 keV). Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is ?03. The X-ray colors of the detected sources indicate a broad variety of source types, although absorbed AGNs (including a small number of possible Compton-thick sources) are clearly the dominant type. We also match lower significance X-ray sources to optical counterparts and provide a list of 79 optically bright (R 23) lower significance Chandra sources. The majority of these sources appear to be starburst and normal galaxies. The average backgrounds in the 0.5?2.0 keV and 2?8 keV bands are 0.056 and 0.135 counts Ms-1 pixel-1, respectively. The background count distributions are very similar to Poisson distributions. We show that this ?2 Ms exposure is approximately photon limited in all seven X-ray bands for regions close to the aim point, and we predict that exposures up to ?25 Ms (0.5?2.0 keV) and ?4 Ms (2?8 keV) should remain nearly photon limited. We demonstrate that this observation does not suffer from source confusion within ?6' of the aim point, and future observations are unlikely to be source-confusion limited within ?3' of the aim point even for source densities exceeding 100,000 deg-2. These analyses directly show that Chandra can achieve significantly higher sensitivities in an efficient, nearly photon-limited manner and be largely free of source confusion. To allow consistent comparisons, we have also produced point-source catalogs for the ?1 Ms Chandra Deep Field South (CDF-S). Three hundred and twenty-six (326) X-ray sources are included in the main Chandra catalog, and an additional 42 optically bright X-ray sources are included in a lower significance Chandra catalog. We find good agreement with the photometry of the previously published CDF-S catalogs; however, we provide significantly improved positional accuracy.

Nitrogen-Doped Mesoporous Carbon Promoted Chemical Adsorption of Sulfur and Fabrication of High-Areal-Capacity Sulfur Cathode with Exceptional Cycling Stability for Lithium-Sulfur Batteries

Abstract: As one important component of sulfur cathodes, the carbon host plays a key role in the electrochemical performance of lithium-sulfur (Li-S) batteries. In this paper, a mesoporous nitrogen-doped carbon (MPNC)-sulfur nanocomposite is reported as a novel cathode for advanced Li-S batteries. The nitrogen doping in the MPNC material can effectively promote chemical adsorption between sulfur atoms and oxygen functional groups on the carbon, as verifi ed by X-ray absorption near edge structure spectroscopy, and the mechanism by which nitrogen enables the behavior is further revealed by density functional theory calculations. Based on the advantages of the porous structure and nitrogen doping, the MPNC-sulfur cathodes show excellent cycling stability (95% retention within 100 cycles) at a high current density of 0.7 mAh cm −2 with a high sulfur loading (4.2 mg S cm −2 ) and a sulfur content (70 wt%). A high areal capacity (≈3.3 mAh cm −2 ) is demonstrated by using the novel cathode, which is crucial for the practical application of Li-S batteries. It is believed that the important role of nitrogen doping promoted chemical adsorption can be extended for development of other high performance carbon-sulfur composite cathodes for Li-S batteries.