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1. Modeling Ocean Color Niche Selection by Synechococcus Blue‐Green Acclimaters

   https://doi.org/10.1029/2021JC017434  

   Lovindeer, R.; Ustick, L. J.; Primeau, F.; Martiny, A. C.; Mackey, K. R. M. (October 2021, Journal of Geophysical Research: Oceans)

   Abstract Light penetration through the ocean creates underwater light color niches and photosynthetic organisms use specific strategies to capture light in these niches. The selection pressure for some cyanobacteria strains in the genusSynechococcusthat change color to absorb either blue or green light (chromatic acclimaters, or generalists) is not well understood. Here, we tested the hypothesis that changes in ocean spectra brought about by mixing preferentially selects for generalists within aSynechococcuspopulation. We investigated ocean conditions that led to high proportions ofSynechococcusgeneralists versus specialists in a model ocean column, and compared simulations with in situ metagenomic and physical oceanographic data from major Bio‐GO‐SHIP cruises, supplemented with GEOTRACES and TARA Oceans, as well as the GOOS Argo Program and sea surface height from AVISO. We found that greater mixed layer depths selected for generalists in simulatedSynechococcuspopulations, but did not account for much of the variance in the partitioning of light‐harvesting strategies in situ. Rather, oceanographic signatures for upwelling areas and ocean fronts explained more of the variation betweenSynechococcusgeneralists and specialists in the ocean. Our results motivate further study of the in situ light environments of upwelling zones and ocean fronts, which are currently understudied as potential light‐driven niche habitats. 

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2. DNA methylation of the endothelin receptor B makes blue fish yellow

   https://doi.org/10.1101/2022.09.27.509821  

   Fang, W; Blakkan, D; Lee, G; Bashier, R; Fernald, RD; Alvarado, SG (September 2022, bioRxiv)

   TBD (Ed.)

   ABSTRACT Natural selection shapes traits during evolution including animal coloration known to be important for concealment and communication and color has been particularly salient in the explosive radiation of cichlid fish species in the rift valley lakes of East Africa. Though selection can produce variation in color via genetic substrates during early development, plasticity in coloration can occur through endocrine, neural and transcriptional cues in response to various environmental stimuli. It is well known that some animals often change color to match their visual ecology. Adult male cichlid fish (Astatotilapia burtoni, Lake Tanganyika) can switch between blue and yellow body colors. Different colors result from the expression of pigment-bearing cells, which differ in density and function between these two color morphs. We show thatA. burtoniswitches from yellow to blue depending on their visual environment by downregulating endothelin receptor B (EdnRB) mRNA via DNA hypermethylation at a single cytosine residue within its promoter. EdnRB functions in yellow chromatophores to signal the aggregation of yellow pigments, making yellow less visible. Taken together, the regulation ofEdnRBthrough DNA methylation in yellow chromatophores, in part, contributes to pigmentation changes from blue to yellow, depending on visual environment. 

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3. A computational and experimental investigation of deep-blue light-emitting tetraaryl-benzobis[1,2- d :4,5- d ′]oxazoles

   https://doi.org/10.1039/d1ma00990g  

   Wheeler, D.; Tannir, S.; Smith, E.; Tomlinson, A.; Jeffries-EL, M. (May 2022, Materials Advances)

   In an effort to design deep-blue light emitting materials for use in OLEDs, the optical and electronic properties of a series of tetraarylbenzobis[1,2- d :4,5- d ′]oxazole (BBO) cruciforms were evaluated using density functional theory (DFT) and time-dependent DFT (TD-DFT). Of the nine possible combinations of phenyl-, furan-2-yl-, and thiophen-2-yl-substituted BBO cruciforms, five were predicted to have ideal optical and electronic properties for use in blue-light emitting diodes. These five cruciforms were synthesized and then characterized electrochemically and spectroscopically. Additionally, they were solution-processed into functional organic light-emitting diodes (OLED). Several of the OLEDs exhibited deep-blue EL ( λ EL < 452 nm; CIE y ≤ 0.12) with maximum luminance efficacies reaching 0.39 lm W −1 and maximum current efficiencies of 0.59 cd A −1 . A comparison of identical device architectures showed that heterocycles such as furan and thiophene helped improve device efficiencies with only a minor red-shift of the electroluminescence (EL). Although these BBO cruciforms produced the desired deep-blue emission their modest performance in host–guest OLEDs demonstrates the incorporation of heterocycles onto the BBO cruciform motif is detrimental to the fluroescence quantum yield. These results add to the knowledge base on structure–property relationships that will inform the design of better blue emitting materials. 

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4. Blue Phosphorescent trans -N-Heterocyclic Carbene Platinum Acetylides: Dependence on Energy Gap and Conformation

   https://doi.org/10.1021/acs.jpca.9b07079  

   Bullock, James D.; Valandro, Silvano R.; Sulicz, Amanda N.; Zeman, Charles J.; Abboud, Khalil A.; Schanze, Kirk S. (October 2019, The Journal of Physical Chemistry A)

   null (Ed.)
5. Toxicity of Refugio Beach Oil to Sand Crabs ( Emerita analoga ), Blue Mussels ( Mytilus sp.), and Inland Silversides ( Menidia beryllina )

   https://doi.org/10.1002/etc.5148  

   Donohoe, Regina M.; Duke, Bryand M.; Clark, Stephen L.; Joab, Bruce M.; Dugan, Jenifer E.; Hubbard, David M.; DaSilva, April R.; Anderson, Michael J. (September 2021, Environmental Toxicology and Chemistry)