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1. Recent Advances in Dual Triplet Ketone/Transition-Metal Catalysis

   https://doi.org/10.1055/s-0042-1751444  

   Iziumchenko, Valeriia; Gevorgyan, Vladimir (July 2023, Synlett)

   Abstract Dual light-excited ketone/transition-metal catalysis is a rapidly developing field of photochemistry. It allows for versatile functionalizations of C–H or C–X bonds enabled by triplet ketone acting as a hydrogen-atom-abstracting agent, a single-electron acceptor, or a photosensitizer. This review summarizes recent developments of synthetically useful transformations promoted by the synergy between triplet ketone and transition-metal catalysis. 1 Introduction 2 Triplet Ketone Catalysis via Hydrogen Atom Transfer 2.1 Triplet Ketones with Nickel Catalysis 2.2 Triplet Ketones with Copper Catalysis 2.3 Triplet Ketones with Other Transition-Metal Catalysis 3 Triplet Ketone Catalysis via Single-Electron Transfer 4 Triplet Ketone Catalysis via Energy Transfer 5 Conclusions 

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2. Dependent type systems as macros

   https://doi.org/10.1145/3371071  

   Chang, Stephen; Ballantyne, Michael; Turner, Milo; Bowman, William_J (December 2019, Proceedings of the ACM on Programming Languages)

   We present Turnstile+, a high-level, macros-based metaDSL for building dependently typed languages. With it, programmers may rapidly prototype and iterate on the design of new dependently typed features and extensions. Or they may create entirely new DSLs whose dependent type ``power'' is tailored to a specific domain. Our framework's support of language-oriented programming also makes it suitable for experimenting with systems of interacting components, e.g., a proof assistant and its companion DSLs. This paper explains the implementation details of Turnstile+, as well as how it may be used to create a wide-variety of dependently typed languages, from a lightweight one with indexed types, to a full spectrum proof assistant, complete with a tactic system and extensions for features like sized types and SMT interaction. 

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3. Bacterial Community Structure Modulates Soil Phosphorus Turnover at Early Stages of Primary Succession

   https://doi.org/10.1029/2024GB008174  

   Wang, Yuhan; Bing, Haijian; Moorhead, Daryl L; Hou, Enqing; Wu, Yanhong; Wang, Jipeng; Duan, Chengjiao; Cui, Qingliang; Zhang, Zhiqin; Zhu, He; et al (October 2024, Global Biogeochemical Cycles)

   Abstract Microbes are the drivers of soil phosphorus (P) cycling in terrestrial ecosystems; however, the role of soil microbes in mediating P cycling in P‐rich soils during primary succession remains uncertain. This study examined the impacts of bacterial community structure (diversity and composition) and its functional potential (absolute abundances of P‐cycling functional genes) on soil P cycling along a 130‐year glacial chronosequence on the eastern Tibetan Plateau. Bacterial community structure was a better predictor of soil P fractions than P‐cycling genes along the chronosequence. After glacier retreat, the solubilization of inorganic P and the mineralization of organic P were significantly enhanced by increased bacterial diversity, changed interspecific interactions, and abundant species involved in soil P mineralization, thereby increasing P availability. Although 84% of P‐cycling genes were associated with organic P mineralization, these genes were more closely associated with soil organic carbon than with organic P. Bacterial carbon demand probably determined soil P turnover, indicating the dominant role of organic matter decomposition processes in P‐rich alpine soils. Moreover, the significant decrease in the complexity of the bacterial co‐occurrence network and the taxa‐gene‐P network at the later stage indicates a declining dominance of the bacterial community in driving soil P cycling with succession. Our results reveal that bacteria with a complex community structure have a prominent potential for biogeochemical P cycling in P‐rich soils during the early stages of primary succession. 

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4. Choosing your own adventure: Engaging the new learning society through integrative curriculum design

   https://doi.org/10.29007/567f  

   Ryder, Elizabeth; Ruiz, Carolina; Weaver, Shari; Gegear, Robert (February 2020, EPiC Series in Education Science)

   In our increasingly data-driven society, it is critical for high school students to learn to integrate computational thinking with other disciplines in solving real world problems. To address this need for the life sciences in particular, we have developed the Bio-CS Bridge, a modular computational system coupled with curriculum integrating biology and computer science. Our transdisciplinary team comprises university and high school faculty and students with expertise in biology, computer science, and education. Our approach engages students and teachers in scientific practices using biological data that they can collect themselves, and computational tools that they help to design and implement, to address the real-world problem of pollinator decline. Our modular approach to high school curriculum design provides teachers with the educational flexibility to address national and statewide biology and computer science standards for a wide range of learner types. We are using a teacher- leader model to disseminate the Bio-CS Bridge, whose components will be freely available online. 

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5. Effects of anaerobic HRT and VFA loading on the kinetics and stoichiometry of enhanced biological phosphorus removal

   https://doi.org/10.1002/wer.1544  

   Coats, Erik R.; Deyo, Brent; Brower, Nicole; Brinkman, Cynthia K. (March 2021, Water Environment Research)

   Abstract Enhanced biological phosphorus removal (EBPR) can recover significant quantities of wastewater phosphorus. However, this resource recovery process realizes limited use largely due to process stability concerns. The research evaluated the effects of anaerobic HRT (τ_AN) and VFA concentration—critical operational parameters that can be externally controlled—on EBPR performance. Evaluated alone, τ_AN(1–4 h) exhibited no statistical effect on effluent phosphorus. However, PHA increased with VFA loading and biomass accumulated more phosphorus. Regarding resiliency, under increasing VFA loads PAOs hydrolyzed more phosphorus to uptake/catabolize VFAs; moreover, PHA synthesis normalized to VFA loading increased with τ_AN, suggesting fermentation. Kinetically, PAOs exhibited a Monod‐like relationships for qPHA_ANand qVFA_ANas a function of anaerobic P release; additionally, qP_AEexhibited a Monod‐like relationship with end‐anaerobic PHA concentration. A culminating analysis affirmed the relationship between enhanced aerobic P uptake, and net P removal, with a parameter (phosphorus removal propensity factor) that combines influent VFA concentration with τ_AN. Practitioner pointsEvaluated alone τ_ANexhibits no statistical effect on effluent phosphorus in an EBPR configuration.Increased PHA synthesis, associated with increased VFAs and/or extended τ_AN,enhances aerobic phosphorus removal.PHA synthesis normalized to VFA loading increased with τ_AN, suggesting fermentation in the EBPR anaerobic zone.Aerobic phosphorus uptake increases linearly with anaerobic phosphorus release, with the slope exceeding unity.Increased VFAs can be substituted for shorter anaerobic HRTs, and vice versa, to enhance EBPR performance. 

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