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1. Attachment and sleep: A dyadic intensive longitudinal actigraphy study

   https://doi.org/10.1177/0265407520958476  

   Haydon, Katherine C.; Moss, Corrin (January 2021, Journal of Social and Personal Relationships)

   null (Ed.)

   Attachment and sleep are linked across the lifespan, but attachment regulation of sleep among couples is understudied. This study aimed to replicate and extend prior research by testing whether romantic partners’ attachment orientations interacted to predict sleep, assessed via self-report and actigraphy over 14 days. Participants ( N = 208 couples) completed measures of attachment anxiety and avoidance and the Pittsburgh Sleep Quality Index. They also wore actigraphy monitors to assess nightly sleep quality and duration. Anxious people self-reported worse sleep quality, replicating two prior studies. In contrast to previous studies, anxious and low-avoidant people slept significantly worse with avoidant partners, while avoidant people slept somewhat better with avoidant partners. Results indicted dyadic regulation of several sleep outcomes and provided new insights regarding how partner avoidance can exacerbate or buffer sleep quality. 

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2. Chiral self-sorting of active semiflexible filaments with intrinsic curvature

   https://doi.org/10.1039/D0SM01163K  

   Moore, Jeffrey M.; Glaser, Matthew A.; Betterton, Meredith D. (January 2021, Soft Matter)

   null (Ed.)

   Many-body interactions in systems of active matter can cause particles to move collectively and self-organize into dynamic structures with long-range order. In cells, the self-assembly of cytoskeletal filaments is critical for cellular motility, structure, intracellular transport, and division. Semiflexible cytoskeletal filaments driven by polymerization or motor-protein interactions on a two-dimensional substrate, such as the cell cortex, can induce filament bending and curvature leading to interesting collective behavior. For example, the bacterial cell-division filament FtsZ is known to have intrinsic curvature that causes it to self-organize into rings and vortices, and recent experiments reconstituting the collective motion of microtubules driven by motor proteins on a surface have observed chiral symmetry breaking of the collective behavior due to motor-induced curvature of the filaments. Previous work on the self-organization of driven filament systems have not studied the effects of curvature and filament structure on collective behavior. In this work, we present Brownian dynamics simulation results of driven semiflexible filaments with intrinsic curvature and investigate how the interplay between filament rigidity and radius of curvature can tune the self-organization behavior in homochiral systems and heterochiral mixtures. We find a curvature-induced reorganization from polar flocks to self-sorted chiral clusters, which is modified by filament flexibility. This transition changes filament transport from ballistic to diffusive at long timescales. 

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3. Enhanced Photoluminescence and Prolonged Carrier Lifetime through Laser Radiation Hardening and Self-Healing in Aged MAPbBr3 Perovskites Encapsulated in NiO Nanotubes

   https://doi.org/10.3390/mi14091706  

   Kamau, Steve; Rodriguez, Roberto Gonzalez; Jiang, Yan; Mondragon, Araceli Herrera; Varghese, Sinto; Hurley, Noah; Kaul, Anupama; Cui, Jingbiao; Lin, Yuankun (September 2023, Micromachines)

   Organic-inorganic perovskites hold great promise as optoelectronic semiconductors for pure color light emitting and photovoltaic devices. However, challenges persist regarding their photostability and chemical stability, which limit their extensive applications. This paper investigates the laser radiation hardening and self-healing-induced properties of aged MAPbBr3 perovskites encapsulated in NiO nanotubes (MAPbBr3@NiO) using photoluminescence (PL) and fluorescence lifetime imaging (FLIM). After deliberately subjecting the MAPbBr3@ NiO to atmospheric conditions for two years, the sample remains remarkably stable. It exhibits no changes in PL wavelength during UV laser irradiation and self-healing. Furthermore, exposure to UV light at 375 nm enhances the PL of the self-healed MAPbBr3@NiO. FLIM analysis sheds light on the mechanism behind photodegradation, self-healing, and PL enhancement. The results indicate the involvement of many carrier-trapping states with low lifetime events and an increase in peak lifetime after self-healing. The formation of trapping states at the perovskite/nanotube interface is discussed and tested. This study provides new insights into the dynamics of photo-carriers during photodegradation and self-healing in organic-inorganic perovskites. 

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4. Self-assembled multifunctional nanostructures for surface passivation and photon management in silicon photovoltaics

   https://doi.org/10.1515/nanoph-2021-0472  

   Hossain, Mohammad Jobayer; Sun, Mengdi; Doerk, Gregory; Kik, Pieter G.; Davis, Kristopher O. (October 2021, Nanophotonics)

   Abstract This work reports the fabrication and characterization of multifunctional, nanostructured passivation layers formed using a self-assembly process that provide both surface passivation and improved light trapping in crystalline silicon photovoltaic (PV) cells. Scalable block copolymer self-assembly and vapor phase infiltration processes are used to form arrays of aluminum oxide nanostructures (Al 2 O 3 ) on crystalline silicon without substrate etching. The Al 2 O 3 nanostructures are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and spectroscopic ellipsometry. Injection-level dependent photoconductance measurements are used to determine the effective carrier lifetime of the samples to confirm the nanostructures successfully passivate the Si surface. Finite element method simulations and reflectance measurement show that the nanostructures increase the internal rear reflectance of the PV cell by suppressing the parasitic optical losses in the metal contact. An optimized morphology of the structures is identified for their potential use in PV cells as multifunctional materials providing surface passivation, photon management, and carrier transport pathways. 

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5. Variable response duration promotes self-organization in decentralized swarms

   https://doi.org/10.1007/978-3-030-63710-1_2  

   Engholdt, Kaelen; Mathias, H. David; Wu, Annie S. (January 2020, Proceedings of the 9th International Conference on Bioinspired Optimisation Methods and Their Applications)

   null (Ed.)

   In self-organizing multi-agent systems, inter-agent variation is known to improve swarm performance significantly. Response duration, the amount of time that an agent spends on a task, has been proposed as a form of inter-agent variation that may be beneficial. In the biological literature, variability in agent response duration in natural swarms for desynchronizing agent actions has been discussed for some time. This form of variation, however, is not well understood in artificial swarms. In this work, we explore inter-agent variation in response duration as a desynchronization technique. We find that variation in response duration does desynchronize agent behaviors and does improve swarm performance on a two-dimensional tracking problem in which the swarm must push a tracker, staying as close as possible to a moving target. By preventing agents from reacting identically to task stimuli and keeping some agents on task longer, response duration helps smooth the swarm’s path and allows it to better track the target into path features such as corners. 

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