1,260 research outputs found

    What’s a threat on social media? How Black and Latino Chicago young men define and navigate threats online

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    Youth living in violent urban neighborhoods increasingly post messages online from urban street corners. The decline of the digital divide and the proliferation of social media platforms connect youth to peer communities who may share experiences with neighborhood stress and trauma. Social media can also be used for targeted retribution when threats and insults are directed at individuals or groups. Recent research suggests that gang-involved youth may use social media to brag, post fight videos, insult, and threaten—a phenomenon termed Internet banging. In this article, we leverage “code of the digital street” to understand how and in what ways social media facilitates urban-based youth violence. We utilize qualitative interviews from 33 Black and Latino young men who frequent violence prevention programs and live in violent neighborhoods in Chicago. Emerging themes describe how and why online threats are conceptualized on social media. Implications for violence prevention and criminal investigations are discussed

    RdgB2 is required for dim-light input into intrinsically photosensitive retinal ganglion cells.

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    A subset of retinal ganglion cells is intrinsically photosensitive (ipRGCs) and contributes directly to the pupillary light reflex and circadian photoentrainment under bright-light conditions. ipRGCs are also indirectly activated by light through cellular circuits initiated in rods and cones. A mammalian homologue (RdgB2) of a phosphoinositide transfer/exchange protein that functions in Drosophila phototransduction is expressed in the retinal ganglion cell layer. This raised the possibility that RdgB2 might function in the intrinsic light response in ipRGCs, which depends on a cascade reminiscent of Drosophila phototransduction. Here we found that under high light intensities, RdgB2(-/-) mutant mice showed normal pupillary light responses and circadian photoentrainment. Consistent with this behavioral phenotype, the intrinsic light responses of ipRGCs in RdgB2(-/-) were indistinguishable from wild-type. In contrast, under low-light conditions, RdgB2(-/-) mutants displayed defects in both circadian photoentrainment and the pupillary light response. The RdgB2 protein was not expressed in ipRGCs but was in GABAergic amacrine cells, which provided inhibitory feedback onto bipolar cells. We propose that RdgB2 is required in a cellular circuit that transduces light input from rods to bipolar cells that are coupled to GABAergic amacrine cells and ultimately to ipRGCs, thereby enabling ipRGCs to respond to dim light

    TROPESS-CrIS CO single-pixel vertical profiles: intercomparisons with MOPITT and model simulations for 2020 western US wildfires

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    The new TROPESS (TRopospheric Ozone and its Precursors from Earth System Sounding) profile retrievals of carbon monoxide (CO) from the Cross-track Infrared Sounder (CrIS) are evaluated against Measurement of Pollution in the Troposphere (MOPITT) CO version 9 data. Comparison results that were adjusted to common a priori constraints in the retrieval processes have improved agreement between the two data sets over direct comparisons. TROPESS-CrIS CO profiles are within 5 % of MOPITT but have higher concentrations in the lower troposphere and lower concentrations in the upper troposphere. For the intense western US wildfire events in September 2020, we compare CO fields simulated by the GISS climate model to the two satellite CO observations. We show intermediate steps of the comparison process to illustrate the evaluation of model simulations by deriving the “retrieved” model CO profiles as they would be observed by the satellite. This includes the application of satellite level-2 data along with their corresponding diagnostic operators provided in the TROPESS-CrIS and MOPITT products. The process allows a diagnosis of potential model improvements in modeling fire emissions and pollution transport.</p

    Going to the exclusive show : exhibition strategies and moviegoing memories of Disneys animated feature films in Ghent (1937-1982)

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    This is a case study of the exploitation and experience of Disney's animated feature films from the 1930s to the 1980s in Ghent (Belgium). It is a historical study of programming practices and financial strategies which constructed childhood memories on watching Disney. The study is a contribution to a historical understanding of the implications of global distribution of film as cultural products and the counter pull of localism. Using a multi-method approach, the argument is made that the scarce screenings were strategically programmed to uplift the moviegoing experience into something out of the ordinary in everyday life. Programming and revenue data characterize the screenings as exclusive and generating high intakes. Consequently, the remembered screenings did not exhale an easy accessible social status nor an image of pervasiveness of popular childhood film, contradictory to conventional accounts of Disney's ubiquity in popular culture

    Coherent oscillations of electrons in tunnel-coupled wells under ultrafast intersubband excitation

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    Ultrafast intersubband excitation of electrons in tunnell-coupled wells is studied depending on the structure parameters, the duration of the infrared pump and the detuning frequency. The temporal dependencies of the photoinduced concentration and dipole moment are obtained for two cases of transitions: from the single ground state to the tunnel-coupled excited states and from the tunnel-coupled states to the single excited state. The peculiarities of dephasing and population relaxation processes are also taken into account. The nonlinear regime of the response is also considered when the splitting energy between the tunnel-coupled levels is renormalized by the photoexcited electron concentration. The dependencies of the period and the amplitude of oscillations on the excitation pulse are presented with a description of the nonlinear oscillations damping.Comment: 8 pages, 12 figure
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