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Creators/Authors contains: "Pham, Tony"

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  1. With the increased demand for Computer Science degrees in the work force, Computer Science is becoming more prominent in high schools. AP Computer Science Principles (AP CSP) is a course that serves as a bridge into Computer Science. Code.org provides a year-long curriculum for this AP course to be led by teachers in the classroom. Beyond an analysis of the pass rates of students, and with the recency of the AP CSP course, a reflection of the AP CSP curriculum from the student’s perspective is in order. This study breaks down the strengths and weaknesses of AP CSP from a student’s perspective. Results show there are many strengths compared to weaknesses in relation to the Code.org curriculum. However, the course can be a little challenging in motivating and engaging students if not executed properly by the teacher. 
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  2. Abstract Metal–organic frameworks (MOFs) can efficiently purify hydrocarbons from CO2, but their rapid saturation, driven by preferential hydrocarbon adsorption, requires energy‐intensive adsorption–desorption processes. To address these challenges, an innovative approach is developed, enabling control over MOF flexibility through densification and defect engineering, resulting in an intriguing inverse CO2/C2 hydrocarbon selectivity. In this study, the densification process induces the shearing of the crystal lattice and contraction of pores in a defective CuBTC MOF. These changes have led to a remarkable transformation in selectivity, where the originally hydrocarbon‐selective CuBTC MOF becomes CO2‐selective. The selectivity values for densified CuBTC are significantly reversed when compared to its powder form, with notable improvements observed in CO2/C2H6(4416 vs 0.61), CO2/C2H4(15 vs 0.28), and CO2/C2H2(4 vs 0.2). The densified material shows impressive separation, regeneration, and recyclability during dynamic breakthrough experiments with complex quinary gas mixtures. Simulation studies indicate faster CO2passage through the tetragonal structure of densified CuBTC compared to C2H2. Experimental kinetic diffusion studies confirm accelerated CO2diffusion over hydrocarbons in the densified MOF, attributed to its small pore window and minimal interparticle voids. This research introduces a promising strategy for refining existing and future MOF materials, enhancing their separation performance. 
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  3. Abstract The capture of the xenon and krypton from nuclear reprocessing off‐gas is essential to the treatment of radioactive waste. Although various porous materials have been employed to capture Xe and Kr, the development of high‐performance adsorbents capable of trapping Xe/Kr at very low partial pressure as in the nuclear reprocessing off‐gas conditions remains challenging. Herein, we report a self‐adjusting metal‐organic framework based on multiple weak binding interactions to capture trace Xe and Kr from the nuclear reprocessing off‐gas. The self‐adjusting behavior of ATC‐Cu and its mechanism have been visualized by the in‐situ single‐crystal X‐ray diffraction studies and theoretical calculations. The self‐adjusting behavior endows ATC‐Cu unprecedented uptake capacities of 2.65 and 0.52 mmol g−1for Xe and Kr respectively at 0.1 bar and 298 K, as well as the record Xe capture capability from the nuclear reprocessing off‐gas. Our work not only provides a benchmark Xe adsorbent but proposes a new route to construct smart materials for efficient separations. 
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  4. Abstract We provide a functional characterization of transcription factor NF-κB in protists and provide information about the evolution and diversification of this biologically important protein. We characterized NF-κB in two protists using phylogenetic, cellular, and biochemical techniques. NF-κB of the holozoanCapsaspora owczarzaki(Co) has an N-terminal DNA-binding domain and a C-terminal Ankyrin repeat (ANK) domain, and its DNA-binding specificity is more similar to metazoan NF-κB proteins than to Rel proteins. Removal of the ANK domain allowsCo-NF-κB to enter the nucleus, bind DNA, and activate transcription. However, C-terminal processing ofCo-NF-κB is not induced by IκB kinases in human cells. OverexpressedCo-NF-κB localizes to the cytoplasm inCocells.Co-NF-κB mRNA and DNA-binding levels differ across threeCapsasporalife stages. RNA-sequencing and GO analyses identify possible gene targets ofCo-NF-κB. Three NF-κB-like proteins from the choanoflagellateAcanthoeca spectabilis(As) contain conserved Rel Homology domain sequences, but lack C-terminal ANK repeats. All threeAs-NF-κB proteins constitutively enter the nucleus of cells, but differ in their DNA-binding abilities, transcriptional activation activities, and dimerization properties. These results provide a basis for understanding the evolutionary origins of this key transcription factor and could have implications for the origins of regulated immunity in higher taxa. 
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