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1. Picoloyl protecting group in synthesis: focus on a highly chemoselective catalytic removal

   https://doi.org/10.1039/D0OB00803F  

   Geringer, Scott A.; Mannino, Michael P.; Bandara, Mithila D.; Demchenko, Alexei V. (July 2020, Organic & Biomolecular Chemistry)

   null (Ed.)

   The picoloyl ester (Pico) has proven to be a versatile protecting group in carbohydrate chemistry. It can be used for the purpose of stereocontrolling glycosylations via an H-bond-mediated Aglycone Delivery (HAD) method. It can also be used as a temporary protecting group that can be efficiently introduced and chemoselectively cleaved in the presence of practically all other common protecting groups used in synthesis. Herein, we will describe a new method for rapid, catalytic, and highly chemoselective removal of the picoloyl group using inexpensive copper( ii ) or iron( iii ) salts. 

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2. Sicopolis-AD: Quick-Start Manual

   https://doi.org/10.2172/1499025  

   Logan, L.C. (January 2019, ANL Technical Report)

   SICOPOLIS-AD is a version of the ice sheet model SICOPOLIS (originally [1]: www.sicopolis.net) used to produce adjoint sensitivities of chosen control variables. It can be used to assess the sensitivity of some quantity of interest to perturbations in variables that may affect that quantity of interest. For example, it can be used to comprehensively and quantitatively assess exactly how the volume of the Greenland Ice Sheet is sensitive to changes in surface temperature at each point on the ice sheet. This document provides basic startup and troubleshooting methods, as well as some best practices for making changes in the code for the purposes of adjoint production. 

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3. STEM education and workforce policy: its history and politics

   Salzman, Hal (February 2023, EBSCO Pathways to Research Salem Press/EBSCO)

   "STEM" is a term that has intuitive appeal but lacks an agreed-upon definition. As such, it has become a term whose ubiquity and ambiguity allow it to be used for a range of policy and political purposes. The longstanding focus on STEM (science, technology, engineering, and mathematics) as a focal point of education and workforce policy makes it important to understand what is considered a STEM field, for what purposes the STEM designation is used, and how it has become a highly politicized term that lacks practical meaning. The use of STEM in policy historically and currently is used to support a range of policy objectives beyond improving science and engineering education or workforce development. 

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4. TCAD Modeling of Cryogenic nMOSFET ON-State Current and Subthreshold Slope

   https://doi.org/10.1109/SISPAD54002.2021.9592586  

   Dhillon, Prabjot; Dao, Nguyen Cong; Leong, Philip H.; Wong, Hiu Yung (September 2021, 2021 International Conference on Simulation of Semiconductor Processes and Devices (SISPAD))

   In this paper, through careful calibration, we demonstrate the possibility of using a single set of models and parameters to model the ON current and Sub-threshold Slope (SS) of an nMOSFET at 300K and 5K using Technology Computer-Aided Design (TCAD). The device used is a 0.35m technology nMOSFET with W/L=10um/10um. We show that it is possible to model the abnormal SS by using interface acceptor traps with a density less than 2×1012cm-2. We also propose trap distribution profiles in the energy space that can be used to reproduce other observed SS from 4K to 300K. Although this work does not prove or disprove any possible origin of the abnormal SS, it shows that one cannot completely rule out the interfacial traps as the origin and it shows that interfacial traps can be used to model the abnormal SS before the origin is fully understood. We also show that Drain-Induced-Barrier-Lowering (DIBL) is much reduced at cryogenic temperature due to the abnormal slope and the device optimization strategy might need to be revised. 

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5. Characterization of oscillation modes in levitated droplets using image and non-image based techniques

   https://doi.org/10.1038/s41526-023-00254-7  

   Brosius, Nevin; Livesay, Jason; Karpinski, Zachary; Singiser, Robert; SanSoucie, Michael; Phillips, Brandon; Narayanan, Ranga (December 2023, npj Microgravity)

   n/a (Ed.)

   Abstract The dynamics of levitated liquid droplets can be used to measure their thermophysical properties by correlating the frequencies at which normal modes of oscillation most strongly resonate when subject to an external oscillatory force. In two preliminary works, it was shown via electrostatic levitation and processing of various metals and alloys that (1) the resonance of the first principal mode of oscillation (moden = 2) can be used to accurately measure surface tension and (2) that so-called “higher-order resonance” ofn = 3 is observable at a predictable frequency. It was also shown, in the context of future space-based experimentation on the Electrostatic Levitation Furnace (ELF), a setup on the International Space Station (ISS) operated by Japan Aerospace Exploration Agency (JAXA), that while the shadow array method in which droplet behavior is visualized would be challenging to identify then = 3 resonance, the normal moden = 4 was predicted to be more easily identifiable. In this short communication, experimental evidence of the first three principal modes of oscillation is provided using molten samples of Tin and Indium and it is subsequently shown that, as predicted, an “image-less approach can be used to identify bothn = 2 andn = 4 resonances in levitated liquid droplets. This suggests that the shadow array method may be satisfactorily used to obtain a self-consistent benchmark of thermophysical properties by comparing results from two successive even-mode natural frequencies. 

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