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1. Damped and driven breathers and metastability

   https://doi.org/10.1090/qam/1650  

   Caballero, Daniel; Wayne, C. Eugene (March 2023, Quarterly of Applied Mathematics)

   In this article we prove the existence of a new family of periodic solutions for discrete, nonlinear Schrödinger equations subject to spatially localized driving and damping. They provide an alternate description of the metastable behavior in such lattice systems which agrees with previous predictions for the evolution of metastable states while providing more accurate approximations to these states. We analyze the stability of these breathers, finding a very small positive eigenvalue whose eigenvector lies almost tangent to the surface of the cylinder formed by the family of breathers. This causes solutions to slide along the cylinder without leaving its neighborhood for very long times. 

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2. Towards accessible and inclusive navigation and wayfinding

   Namboodiri, Vinod (May 2019, Workshop on Hacking Blind Navigation at CHI 2019)

   This paper presents a brief overview of the various (related) research the author has been involved with in the area of navigation and wayfinding for people with visual impairments. The first major piece of research presented is that of the building and deployment of a beacon-based indoor navigation and wayfinding system called GuideBeacon for people with visual impairments. The second major piece of research presented is a broader community-based effort called CityGuide to enable various location-based services (including navigation and wayfinding) in both indoor and outdoor environments for people with disabilities. The paper concludes by summarizing a specific challenge in the area that warrant future research attention. 

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3. Raman Spectroscopy and Modeling and Simulation of Quantum Dots and Nanomaterials for Optoelectronic and Sensing Applications

   https://doi.org/10.32604/icces.2024.013296  

   Misra, Prabhakar; Alghamdi, Hawazin; Garcia-Sanchez, Raul; Mitchell, Wyatt; Powell, Allison; Vohra, Nikhil (January 2024, The International Conference on Computational & Experimental Engineering and Sciences)

   Semiconducting quantum dots (Q-dots) with strain-tunable electronic properties are good contenders for quantum computing devices, as they hold promise to exhibit a high level of photon entanglement. The optical and electronic properties of Q-dots vary with their size, shape, and makeup. An assortment of Q-dots has been studied, including ZnO, ZnS, CdSe and perovskites [1]. We have employed both Raman spectroscopy (to precisely determine their vibrational frequencies) and UV-VIS spectroscopy (to determine accurately their band gap energies). The electronic band structure and density of states of the ZnO and ZnS Q-dots have been investigated under strain using Density Functional Theory (DFT). The computer program SIESTA (Spanish Initiative for Electronic Simulations with Thousands of Atoms) was used to perform the DFT calculations via the linear combination of atomic orbitals (LCAO) method. The spin polarization of such systems may itself be used to encode information or influence the electronic properties of semiconducting Q-dots, which deserve special attention, as they have potential applications in lasers, photovoltaic cells, and imaging. In addition, we have investigated pristine and functionalized graphene nanoplatelets and metal oxides for sensing applications. 

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4. The Factory and the Beehive. V. Chromospheric and Coronal Activity and Its Dependence on Rotation in Praesepe and the Hyades

   Núñez, Alejandro; Agüeros, Marcel A; Curtis, Jason L; Covey, Kevin R; Douglas, Stephanie T; Chu, Sabine R; DeLaurentiis, Stanislav; Wang, Minzhi; Drake, Jeremy J (February 2024, The Astrophysical journal)

   Low-mass (<1.2 Msun) main-sequence stars lose angular momentum over time, leading to a decrease in their magnetic activity. The details of this rotation–activity relation remain poorly understood, however. Using observations of members of the ≈700 Myr old Praesepe and Hyades open clusters, we aim to characterize the rotation–activity relation for different tracers of activity at this age. To complement published data, we obtained new optical spectra for 250 Praesepe stars, new X-ray detections for 10, and new rotation periods for 28. These numbers for Hyads are 131, 23, and 137, respectively. The latter increases the number of Hyads with periods by 50%. We used these data to measure the fractional Hα and X-ray luminosities, LHα/Lbol and LX/Lbol, and to calculate Rossby numbers Ro. We found that at ≈700 Myr almost all M dwarfs exhibit Hα emission, with binaries having the same overall color–Hα equivalent width distribution as single stars. In the Ro–LHα/Lbol plane, unsaturated single stars follow a power law with index β = −5.9 ± 0.8 for Ro > 0.3. In the Ro–LX/Lbol plane, we see evidence for supersaturation for single stars with R < 0.01, following a power law with index βsup = 0.5(+0.2,-0.1) supporting the hypothesis that the coronae of these stars are being centrifugally stripped. We found that the critical Ro value at which activity saturates is smaller for LX/Lbol than for LHα/Lbol. Finally, we observed an almost 1:1 relation between LHα/Lbol and LX/Lbol, suggesting that both the corona and the chromosphere experience similar magnetic heating. 

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5. Why and How to Account for Sex and Gender in Brain and Behavioral Research

   https://doi.org/10.1523/JNEUROSCI.0020-23.2023  

   Eliot, Lise; Beery, Annaliese K.; Jacobs, Emily G.; LeBlanc, Hannah F.; Maney, Donna L.; McCarthy, Margaret M. (September 2023, The Journal of Neuroscience)

   Long overlooked in neuroscience research, sex and gender are increasingly included as key variables potentially impacting all levels of neurobehavioral analysis. Still, many neuroscientists do not understand the difference between the terms “sex” and “gender,” the complexity and nuance of each, or how to best include them as variables in research designs. This TechSights article outlines rationales for considering the influence of sex and gender across taxa, and provides technical guidance for strengthening the rigor and reproducibility of such analyses. This guidance includes the use of appropriate statistical methods for comparing groups as well as controls for key covariates of sex (e.g., total intracranial volume) and gender (e.g., income, caregiver stress, bias). We also recommend approaches for interpreting and communicating sex- and gender-related findings about the brain, which have often been misconstrued by neuroscientists and the lay public alike. 

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