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1. Minimal overall divergence of the gut microbiome in an adaptive radiation of Cyprinodon pupfishes despite potential adaptive enrichment for scale-eating

   https://doi.org/10.1371/journal.pone.0273177  

   Heras, Joseph ; Martin, Christopher H. ( September 2022 , PLOS ONE)

   Meyer, Axel (Ed.)

   Adaptive radiations offer an excellent opportunity to understand the eco-evolutionary dynamics of gut microbiota and host niche specialization. In a laboratory common garden, we compared the gut microbiota of two novel derived trophic specialist pupfishes, a scale-eater and a molluscivore, to closely related and distant outgroup generalist populations, spanning both rapid trophic evolution within 10 kya and stable generalist diets persisting over 11 Mya. We predicted an adaptive and highly divergent microbiome composition in the trophic specialists reflecting their rapid rates of craniofacial and behavioral diversification. We sequenced 16S rRNA amplicons of gut microbiomes from lab-reared adult pupfishes raised under identical conditions and fed the same high protein diet. In contrast to our predictions, gut microbiota largely reflected phylogenetic distance among species, rather than generalist or specialist life history, in support of phylosymbiosis. However, we did find significant enrichment of Burkholderiaceae bacteria in replicated lab-reared scale-eater populations. These bacteria sometimes digest collagen, the major component of fish scales, supporting an adaptive shift. We also found some enrichment of Rhodobacteraceae and Planctomycetia in lab-reared molluscivore populations, but these bacteria target cellulose. Overall phylogenetic conservation of microbiome composition contrasts with predictions of adaptive radiation theory and observations of rapid diversification in all other trophic traits in these hosts, including craniofacial morphology, foraging behavior, aggression, and gene expression, suggesting that the functional role of these minor shifts in microbiota will be important for understanding the role of the microbiome in trophic diversification. 

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2. Non-adaptive vs Adaptive Queries in the Dense Graph Testing Model

   https://doi.org/10.1109/FOCS52979.2021.00035  

   Goldreich, Oded ; Wigderson, Avi ( February 2022 , 2021 IEEE 62nd Annual Symposium on Foundations of Computer Science (FOCS))

   We study the relation between the query complexity of adaptive and non-adaptive testers in the dense graph model. It has been known for a couple of decades that the query complexity of non-adaptive testers is at most quadratic in the query complexity of adaptive testers. We show that this general result is essentially tight; that is, there exist graph properties for which any non-adaptive tester must have query complexity that is almost quadratic in the query complexity of the best general (i.e., adaptive) tester. More generally, for every q: N→N such that q(n)≤n−−√ and constant c∈[1,2], we show a graph property that is testable in Θ(q(n)) queries, but its non-adaptive query complexity is Θ(q(n)c), omitting poly(log n) factors and ignoring the effect of the proximity parameter ϵ. Furthermore, the upper bounds hold for one-sided error testers, and are at most quadratic in 1/ϵ. These results are obtained through the use of general reductions that transport properties of ordered structured (like bit strings) to those of unordered structures (like unlabeled graphs). The main features of these reductions are query-efficiency and preservation of distance to the properties. This method was initiated in our prior work (ECCC, TR20-149), and we significantly extend it here. 

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3. In-memory integration of existing software components for parallel adaptive unstructured mesh workflows: In-memory integration of existing software components for parallel adaptive unstructured mesh workflows

   https://doi.org/10.1002/cpe.4510  

   Smith, Cameron W. ; Granzow, Brian ; Diamond, Gerrett ; Ibanez, Daniel ; Sahni, Onkar ; Jansen, Kenneth E. ; Shephard, Mark S. ( September 2018 , Concurrency and Computation: Practice and Experience)
4. Adaptive Dynamic Programming and Data-Driven Cooperative Optimal Output Regulation with Adaptive Observers

   https://doi.org/10.1109/CDC51059.2022.9993124  

   Qasem, Omar ; Jebari, Khalid ; Gao, Weinan ( January 2022 , 2022 IEEE 61st Conference on Decision and Control (CDC))
5. Evaluating the performance of the Keck Observatory adaptive optics systems on crowded field data using different adaptive optics configurations

   https://doi.org/10.1117/12.2629035  

   Chu, Devin ; Ning, Wenmeng ; Do, Tuan ; Ghez, Andrea ; Wizinowich, Peter ; Lu, Jessica ; Gautam, Abhimat K. ; Ciurlo, Anna ; Terry, Sean ; Lyke, Jim E. ; et al ( September 2022 , Adaptive Optics Systems VIII)

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

   We present evaluations of the Keck Telescope’s adaptive optics (AO) performance on Milky Way Galactic center imaging and spectroscopic observations using three different AO setups: laser guide star with infrared (IR) tip-tilt correction, laser guide star with visible tip-tilt correction, and infrared natural guide star with a pyramid wavefront sensor. Observations of the Galactic Center can utilize a bright IR tip-tilt star (K′ = 7.4 mag) for corrections, which is over 10 arcseconds closer than the optical tip-tilt star. The proximity of this IR star enables the comparison of the aforementioned AO configurations. We present performance metrics such as full-width-at-half-maximum (FWHM), Strehl ratio, and spectral signal to noise ratio and their relations to atmospheric seeing conditions. The IR tip-tilt star decreases the median spatial FWHM by 31% in imaging data and 30% in spectroscopy. Median Strehl for imaging data improves by 24%. Additionally, the IR star removes the seeing dependence from differential tip-tilt error in both imaging and spectroscopic data. This evaluation provides important work for ongoing upgrades to AO systems, such as the Keck All sky Precision Adaptive Optics (KAPA) upgrade on the Keck I Telescope, and the development of new AO systems for extremely large telescopes. 

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