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  1. Maintaining confidential information control in software is a persistent security problem where failure means secrets can be revealed via program behaviors. Information flow control techniques traditionally have been based on static or symbolic analyses — limited in scalability and specialized to particular languages. When programs do leak secrets there are no approaches to automatically repair them unless the leak causes a functional test to fail. We present our vision for HyperGI, a genetic improvement framework that detects, localizes and repairs information leakage. Key elements of HyperGI include (1) the use of two orthogonal test suites, (2) a dynamic leak detectionmore »approach which estimates and localizes potential leaks, and (3) a repair component that produces a candidate patch using genetic improvement. We demonstrate the successful use of HyperGI on several programs with no failing functional test cases. We manually examine the resulting patches and identify trade-offs and future directions for fully realizing our vision.« less
    Free, publicly-accessible full text available November 1, 2022
  2. This paper analyzes the computational practices that four 7th and 8th grade students engaged in when learning geometric transformations in two different online block-based programming environments. The data sources include video footage of students’ interviews in Zoom where they shared their screens and cameras. The findings determined that students utilized in particular, decomposition and pattern recognition as important computational thinking practices required for learning in STEM disciplines. The paper also describes the changes made in how research method, data collection, and analysis configured opportunities to study computational thinking in remote locations due to the restrictions brought on by COVID-19. Wemore »identified three main challenges in the transition to online research: (a) recruiting research participants which included instituting necessary revisions to ethics protocols; (b) rethinking data gathering and analysis techniques along with interactions with participants in virtual settings; (c) dealing with glitches associated with technologies and virtual communication media in just-in-time ways. We conclude that even given the challenges with researching during COVID-19, there are still opportunities for rich, robust research in online settings.« less
  3. Abstract

    Convergent research identifies a general factor (“P factor”) that confers transdiagnostic risk for psychopathology. Large-scale networks are key organizational units of the human brain. However, studies of altered network connectivity patterns associated with the P factor are limited, especially in early adolescence when most mental disorders are first emerging. We studied 11,875 9- and 10-year olds from the Adolescent Brain and Cognitive Development (ABCD) study, of whom 6593 had high-quality resting-state scans. Network contingency analysis was used to identify altered interconnections associated with the P factor among 16 large-scale networks. These connectivity changes were then further characterized with quadrantmore »analysis that quantified the directionality of P factor effects in relation to neurotypical patterns of positive versus negative connectivity across connections. The results showed that the P factor was associated with altered connectivity across 28 network cells (i.e., sets of connections linking pairs of networks);pPERMUTATIONvalues < 0.05 FDR-corrected for multiple comparisons. Higher P factor scores were associated with hypoconnectivity within default network and hyperconnectivity between default network and multiple control networks. Among connections within these 28 significant cells, the P factor was predominantly associated with “attenuating” effects (67%;pPERMUTATION < 0.0002), i.e., reduced connectivity at neurotypically positive connections and increased connectivity at neurotypically negative connections. These results demonstrate that the general factor of psychopathology produces attenuating changes across multiple networks including default network, involved in spontaneous responses, and control networks involved in cognitive control. Moreover, they clarify mechanisms of transdiagnostic risk for psychopathology and invite further research into developmental causes of distributed attenuated connectivity.

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  4. In previous papers, Lehr and Sicker (2018a,b) argued that the changing character of our telecommunications infrastructure called for a new regulatory approach, with a new Communications Act to define the duties and authorities of a reconceptualized FCC (what we call newFCC in this paper). Today's Internet ecosystem is comprised of multiple digital network platforms organized into a multi-layer architecture. Lower layer IP platforms provided by access and backbone ISPs collectively support the Internet, on which complementors can build higher-layer platforms, such as the platforms provided by powerful firms such as Google, Microsoft, Amazon, Facebook and Apple. These firms control andmore »operate multiple platforms within the larger Internet ecosystem. When dominant platform providers pursue multi-platform strategies in an effort to capture or control a market, such strategies confound current methods for defining markets and assessing market power. This paper draws on the layered platform nature of the Internet ecosystem, as described in Claffy and Clark (2014), to illustrate how this layered character of today’s Internet ecosystem calls for new regulatory authority. This paper draws on the layered platform model to scope the duties for an agency (or agencies) with sector-specific expertise.« less