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Solving transient energy transport is crucial for accurately predicting the behavior of materials and devices during thermal cycling, pulsed heating, and transient operational states where heat generation and dissipation rates vary over time. Traditional methods, like the finite difference and element methods, discretize space and time and update temperature values at each grid point iteratively over time steps. Its straightforward implementation makes it popular for solving heat transfer problems. However, when high temporal and spatial resolutions or prolonged heating durations are required, the computational demand rises significantly, leading to significantly greater resource consumption. To address this, in this work we develop a new method termed Complex-modeling with Fourier Transform (CFT) that enables rapid and efficient simulations of transient energy transport problems. The CFT method decomposes the periodical heating problem into a complex-temperature energy transport problem with a single harmonic heat source. 1D and 3D transient heat conduction problems (conjugated with hot carrier transfer) are solved using the CFT method to demonstrate its effectiveness. The CFT method produces similar or higher accuracy results compared with the finite difference method, while the computational speed is increased by more than two orders of magnitude. We also developed a new method termed Complex-modeling with Fourier and Heaviside Transforms (CFHT) that can solve any transient energy transport problems with orders of magnitude speed increase. The CFT and CFHT methods developed in this work are applicable to linear problems that could involve mechanical, thermal, optical, and electrical responses. 

This qualitative study examined the college pathways of mostly working-class immigrant-origin youth of color (Black, East Asian, Latino/a) in New York City. Using a thematic analysis approach with bridging multiple worlds theory and social capital theory as guiding conceptual frameworks, we examined facilitators and barriers that 30 working-class immigrant-origin youth of color encountered in different worlds (family, school, peers, and community programs) in their college pathways. Our analysis found that most students received emotional but not instrumental support from their parents, notably that their parents mainly wanted them to be happy and to pursue a college degree that would lead to non-blue-collar work. Students received emotional and instrumental guidance from school staff, and many students received help from, and in return helped, their peers. Students who had access to community programs and external resources found them to be helpful in receiving feedback on college application materials and perspectives about different career paths. Students also noted barriers, including family circumstances and immigration status, that hindered their college pathways. We discuss similarities and differences in facilitators and barriers that different racial groups experienced, as well as contributions to literature and implications for removing barriers for immigrant-origin youth of color. (PsycInfo Database Record (c) 2024 APA, all rights reserved) 

Abstract The morphology and motion of auroras have been widely studied due to their indications on magnetospheric processes. Here, we report a new kind of “auroral curls,” which have wavelengths in the mesoscale (∼100 km) and propagate azimuthally. Utilizing data from the Chinese Antarctic Zhongshan Station (the all‐sky imager and the high‐frequency radar), the Active Magnetosphere and Planetary Electrodynamics Response Experiment and the Defense Meteorological Satellite Program, we analyze an event occurred on 23 April 2019. We find these curls are fine structures in the poleward boundary of multiple arcs. Corresponding field‐aligned currents manifest as a series of longitudinally arranged pairs, while ionospheric flow velocities nearby oscillate with periods in the Pc 5 band. Observational evidence suggests these curls are connected with ultra‐low frequency (ULF) waves, which opens the possibility of using auroras to globally image ULF waves.