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Superconductivity had been one of the most enigmatic phenomena in condensed matter physics, puzzling the best theorists for 45 years, since the original discovery by Kamerlingh-Onnes in 1911 till the final solution by Bardeen, Cooper, and Schrieffer (BCS) in 1957. The original BCS proposal assumed the highest-symmetry form for the superconducting order parameter Δ, namely, a constant, and a uniform pairing interaction due to attractive mediation of ionic vibration. While it was rather soon realized that generalizations onto k-dependent order parameters and anisotropic pairing interaction was straightforward, only thirty years later, upon the discovery of high-temperature superconductivity in cuprates, high-order angular dependence of Δ and repulsive interaction, mediated by spin fluctuations or Coulomb repulsion brought such “unconventional” into the spotlight. In 2008 yet another such system was discovered, and eventually the idea of repulsion-mediated unconventional superconductivity was generally accepted. Apart from the two specific systems mentioned above, a large number of various specific implementations of this idea have been proposed, and it is becoming increasingly clear that it is worth studying mathematically how unconventional superconductivity emerges, and with what properties, for a simple, but sufficiently general theoretical model. In our project, we study systematically unconventional superconductivity in an isotropic two-dimensional model system of electrons, subjected to repulsive interactions of a simple, but physically motivated form: a delta function peaked at a particular momentum (from 0 to twice the Fermi momentum), or Gaussian of varying widths. 

Humans understand videos from both the visual and audio aspects of the data. In this work, we present a self supervised cross modal representation approach for learning audio visual correspondence (AVC) for videos in the wild. After the learning stage, we explore retrieval in both cross modal and intra modal manner with the learned representations. We verify our experimental results on the VGGSound dataset and our approach achieves promising results. 

Cybersecurity workforce development is the key to protecting information and information systems, and yet more than 30% of companies are short on security expertise. To address this need, the current authors have developed four cybersecurity education games to teach social engineering, secure online behavior, cyber defense methods, and cybersecurity first principles. These games are intended to recruit the next generation cybersecurity workforce by developing an innovative cybersecurity curriculum and pedagogical methods to provide high school students with hands-on activities in a game-based learning environment. Purdue University Northwest (PNW) offered high school summer camps for 181 high school students in June of 2016 and June of 2017. Out of 181 high school participants, 107 were underrepresented minority students, including African Americans, Hispanics, Asians, and Native Americans. To evaluate the effectiveness of the cybersecurity education games, post-camp surveys were conducted with 154 camp participants. The survey results indicated that the games were very effective in cybersecurity awareness training. Furthermore, the cybersecurity education games were more effective for male students than female students in raising student interest in computer science and cybersecurity. 

Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H 2 O + , remains elusive. We used tunable femtosecond soft x-ray pulses from an x-ray free electron laser to reveal the dynamics of the valence hole created by strong-field ionization and to track the primary proton transfer reaction giving rise to the formation of OH. The isolated resonance associated with the valence hole (H 2 O + /OH) enabled straightforward detection. Molecular dynamics simulations revealed that the x-ray spectra are sensitive to structural dynamics at the ionization site. We found signatures of hydrated-electron dynamics in the x-ray spectrum.