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1. Advances in Selected Heterocyclization Methods

   https://doi.org/10.1055/s-0042-1751429  

   Rivas, Mónica; Gevorgyan, Vladimir (July 2023, Synlett)

   Abstract This Account summarizes efforts in our group toward synthesis of heterocycles in the past decade. Selected examples of transannulative heterocyclizations, intermediate construction of reactive compounds en route to these important motifs, and newer developments of a radical approach are outlined. 1 Introduction 2 Transannulative Heterocyclization 2.1 Rhodium-Catalyzed Transannulative Heterocyclization 2.2 Copper-Catalyzed Transannulative Heterocyclization 3 Synthesis of Heterocycles from Reactive Precursors 3.1 Synthesis of Heterocycles from Diazo Compounds 3.2 Synthesis of Heterocycles from Alkynones 4 Radical Heterocyclization 4.1 Light-Induced Radical Heterocyclization 4.2 Light-Free Radical Heterocyclization 7 Conclusion 

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2. Changes in foliar chemistry and nutrient resorption in northern hardwood forests in response to long‐term experimental nitrogen and phosphorus addition

   https://doi.org/10.1111/oik.10867  

   Zukswert, Jenna M; Fahey, Timothy J; Vadeboncoeur, Matthew A; Hong, Daniel S; Yanai, Ruth D (February 2025, Oikos)

   Northern hardwood forests have long been assumed to be primarily nitrogen limited, but may often be co‐limited by multiple elements. Nutrient limitation can be inferred through responses of foliar and litter chemistry to nutrient addition over time. We compared community‐level foliar and litter chemistry and resorption efficiency in a long‐term, factorial nitrogen (N) and phosphorus (P) fertilization study across 10 forest stands at three sites in New Hampshire, where N and P were added annually. We measured N, P, calcium (Ca), magnesium (Mg), and potassium (K) in foliage from codominant trees and in fresh litter in 2008–2010 (pretreatment) and again in 2014–2016 and 2021–2022. Foliar N and P concentrations indicated co‐limitation in 2014–2016 based on reduced concentrations of one nutrient following addition of the other, suggesting a dilution effect. In 2021–2022, an interactive effect of N and P addition was observed: foliar P concentrations were lower under N+P addition, consistent with dilution following a greater growth response to N + P than to P addition, which was observed by 2015–2019. Changes in litter N and P concentrations with N and P addition mirrored those in foliar N and P. Resorption efficiency of N and P decreased with addition of these respective nutrients and P resorption efficiency was higher in the N+P treatment than the P treatment. Foliar Ca and litter Ca and K decreased with N addition but increased with P addition. Results indicated N and P co‐limitation and revealed biogeochemical interactions among N, P and base cations. 

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3. Multi-instantons in minimal string theory and in matrix integrals

   https://doi.org/10.1007/JHEP10(2022)065  

   Eniceicu, Dan Stefan; Mahajan, Raghu; Murdia, Chitraang; Sen, Ashoke (October 2022, Journal of High Energy Physics)

   A<sc>bstract</sc> We compute the normalization of the general multi-instanton contribution to the partition function of (p′,p) minimal string theory and also to the dual two-matrix integral. We find perfect agreement between the two results. 

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4. Convex polytopes in restricted point sets in R^d

   https://doi.org/10.19086/aic.2025.1  

   Bukh, Boris; Zichao, Dong (January 2025, Advances in Combinatorics)

   For a finite point set P⊂R^d, denote by diam(P) the ratio of the largest to the smallest distances between pairs of points in P. Let c_{d,α}(n) be the largest integer c such that any n-point set P⊂R^d in general position, satisfying diam(P)<αn^{1/d}, contains an c-point convex independent subset. We determine the asymptotics of c_{d,α}(n) as n→∞ by showing the existence of positive constants β=β(d,α) and γ=γ(d) such that βn^{(d−1)/(d+1)}≤c_{d,α}(n)≤γn^{(d−1)/(d+1)} for α≥2. 

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5. Variation in responses to temperature in admixed Populus genotypes predicts geographic shifts in regions where hybrids are favored

   https://doi.org/10.1111/nph.70787  

   Mead, Alayna; Beasley‐Bennett, Joie R; Bleich, Andrew; Fischer, Dylan; Flint, Shelby; Golightly, Julie; Kalcsits, Lee; Klopf, Sara K; Kulbaba, Mason W; Lasky, Jesse R; et al (November 2025, New Phytologist)

   Summary Plastic responses of plants to their environment vary as a result of genetic differentiation within and among species. To accurately predict rangewide responses to climate change, it is necessary to characterize genotype‐specific reaction norms across the continuum of historic and future climate conditions comprising a species' range.The North American hybrid zone ofPopulus trichocarpaandPopulus balsamiferarepresents a natural system that has been shaped by climate, geography, and introgression. We leverage a dataset containing 44 clonal genotypes from this natural hybrid zone, planted across 17 replicated common garden experiments spanning a broad climatic range. Growth and mortality were measured over 2 yr, enabling us to model reaction norms for each genotype across these tested environments.Species ancestry and intraspecific genomic variation significantly influenced growth across environments, with genotypic variation in reaction norms reflecting a trade‐off between cold tolerance and growth. Using modeled reaction norms for each genotype, we predicted that genotypes with moreP. trichocarpaancestry may gain an advantage under warmer climates.Spatial shifts of the hybrid zone could facilitate the spread of beneficial alleles into novel climates. These results highlight that genotypic variation in responses to temperature will have landscape‐level effects. 

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