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1. Microfabricated Low-Profile Tunable LC-Refractive Fresnel (LCRF) Lens for Smart Contacts

   https://doi.org/10.1364/CLEO_AT.2022.AW4C.3  

   Banerjee, Aishwaryadev; Ghosh, Chayanjit; Karkhanis, Mohit; Deshpande, Adwait; Pourshaban, Erfan; Kim, Hanseup; Mastrangelo, Carlos H. (January 2022, Conference on Lasers and Electro-Optics (CLEO))

   Using high-performance LC (E7) filled microfabricated refractive Fresnel chambers, we experimentally demonstrate a thin low-profile adaptive optical system with high analog tunability (2.1 D) that can be integrated with an adaptive contact-lens system. 

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2. Multiscale adaptive management of social–ecological systems

   https://doi.org/10.1093/biosci/biad096  

   Garmestani, Ahjond; Allen, Craig R; Angeler, David G; Gunderson, Lance; Ruhl, J B (November 2023, BioScience)

   Abstract Adaptive management is an approach for stewardship of social–ecological systems in circumstances with high uncertainty and high controllability. Although they are largely overlooked in adaptive management (and social–ecological system management), it is important to account for spatial and temporal scales to mediate within- and cross-scale effects of management actions, because cross-scale interactions increase uncertainty and can lead to undesirable consequences. The iterative nature of an adaptive approach can be expanded to multiple scales to accommodate different stakeholder priorities and multiple ecosystem attributes. In this Forum, we introduce multiscale adaptive management of social–ecological systems, which merges adaptive management with panarchy (a multiscale model of social–ecological systems) and demonstrate the importance of this approach with case studies from the Great Plains of North America and the Platte River Basin, in the United States. Adaptive management combined with a focus on the panarchy model of social–ecological systems can help to improve the management of social–ecological systems. 

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3. Persistent and responsive collective motion with adaptive time delay

   https://doi.org/10.1126/sciadv.adk3914  

   Chen, Zhihan; Zheng, Yuebing (April 2024, Science Advances)

   It is beneficial for collective structures to simultaneously have high persistence to environmental noise and high responsivity to nontrivial external stimuli. However, without the ability to differentiate useful information from noise, there is always a tradeoff between persistence and responsivity within the collective structures. To address this, we propose adaptive time delay inspired by the adaptive behavior observed in the school of fish. This strategy is tested using particles powered by optothermal fields coupled with an optical feedback-control system. By applying the adaptive time delay with a proper threshold, we experimentally observe the responsivity of the collective structures enhanced by approximately 1.6 times without sacrificing persistence. Furthermore, we integrate adaptive time delay with long-distance transportation and obstacle-avoidance capabilities to prototype adaptive swarm microrobots. This research demonstrates the potential of adaptive time delay to address the persistence-responsivity tradeoff and lays the foundation for intelligent swarm micro/nanorobots operating in complex environments. 

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4. Fast and furious focal-plane wavefront sensing at W.M. Keck Observatory

   https://doi.org/10.1117/12.2596147  

   Bos, Steven P.; Bottom, Michael; Ragland, Sam; Delorme, Jacques-Robert; Cetre, Sylvain; Pueyo, Laurent (August 2021, Proc. SPIE 11823, Techniques and Instrumentation for Detection of Exoplanets X, 118231E)

   Shaklan, Stuart B.; Ruane, Garreth J. (Ed.)

   High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky point-spread function delivered by the adaptive optics system can require further optimization to correct unsensed static aberrations and calibration biases. We investigated using the Fast and Furious focal-plane wavefront sensing algorithm as a potential solution. This algorithm uses a simple model of the optical system and focal plane information to measure and correct the point-spread function phase, without using defocused images, meaning it can run concurrently with science. On-sky testing demonstrated significantly improved PSF quality in only a few iterations, with both narrow and broadband filters. These results suggest this algorithm is a useful path forward for creating and maintaining high-quality, repeatable on-sky adaptive optics point-spread functions. 

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5. Design and development of a high-speed visible pyramid wavefront sensor for the MMT AO system

   https://doi.org/10.1117/12.2576353  

   Anugu, Narsireddy; Durney, Olivier; M. Morzinski, Katie; Hinz, Phil; Sivanandam, Suresh; Males, Jared; Gardner, Andrew K.; Fellows, Chuck; Montoya, Manny; West, Grant; et al (December 2020, Proceedings of the SPIE)

   Schmidt, Dirk; Schreiber, Laura; Vernet, Elise (Ed.)

   MAPS, MMT Adaptive optics exoPlanet characterization System, is the upgrade of the adaptive optics system for 6.5-m MMT. It is an NSF MSIP-funded project that includes developing an adaptive-secondary mirror, visible and near-infrared pyramid wavefront sensors, and the upgrade of Arizona infrared imager and echelle spectrograph (ARIES) and MMT High Precision Imaging Polarimeter (MMTPol) science cameras. This paper will present the design and development of the visible pyramid wavefront sensor, VPWFS. It consists of an acquisition camera, a fast-steering tip-tilt modulation mirror, a pyramid, a pupil imaging triplet lens, and a low noise and high-speed frame rate based CCID75 camera. We will report on hardware and software, present the laboratory characterization results of individual subsystems, and outline the on-sky commissioning plan. 

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