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1. Three dimensional topological quantum field theory from U_q(gl(1,1)) and U(1,1) Chern–Simons theory

   https://doi.org/10.1016/j.aim.2024.110044  

   Geer, Nathan; Young, Matthew B (November 2024, Advances in Mathematics)

   We introduce an unrolled quantization U_q^E(gl(1,1)) of the complex Lie superalgebra gl(1,1) and use its categories of weight modules to construct and study new three dimensional non-semisimple topological quantum field theories. These theories are defined on categories of cobordisms which are decorated by ribbon graphs and cohomology classes and take values in categories of graded super vector spaces. Computations in these theories are enabled by a detailed study of the representation theory of U_q^E(gl(1,1)). We argue that by restricting to subcategories of integral weight modules we obtain topological quantum field theories which are mathematical models of Chern--Simons theories with gauge supergroups psl(1,1,) and U(1,1) coupled to background flat \mathbb{C}^{\times}-connections, as studied in the physics literature by Rozansky--Saleur and Mikhaylov. In particular, we match Verlinde formulae and mapping class group actions on state spaces of non-generic tori with results in the physics literature. We also obtain explicit descriptions of state spaces of generic surfaces, including their graded dimensions, which go beyond results in the physics literature. 

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2. Giant Electrostriction via Nanodomain Engineering in Relaxor Ferroelectric Polymers

   https://doi.org/10.1021/acsnano.5c10388  

   Zou, Qin; Rui, Guanchun; Wu, Siyu; Zhang, Honghu; Taylor, Philip L; Zhu, Lei (August 2025, ACS nano)

   Relaxor ferroelectric (RFE) polymers hold great promise for artificial muscles due to their high actuation strain, high loading stress, and fast response. However, the structural origin underlying their large electrostrictive deformation remains elusive. In this study, we investigate poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)]-based RFE terpolymers, incorporating 1,1-chlorofluoroethylene (CFE) or chlorotrifluoroethylene (CTFE) (the terpolymers are denoted as terP-CFE and terP-CTFE, respectively) as termonomers. Although both terpolymers show similar semicrystalline morphology, drastically different electrostrictive properties are observed. Specifically, the terP-CFE annealed at 100 °C achieves a record-high transverse strain of ~10.6%, whereas 100 °C-annealed terP-CTFE only shows a much lower actuation strain of ~4.2% at the same poling field of 190 MV/m. To elucidate the origin of this difference, time-resolved wide-angle X-ray diffraction, small-angle X-ray scattering, and Fourier transform infrared experiments are performed during in-situ electric poling. An RFE-to-ferroelectric (FE) crystal phase transition is observed for terP-CFE, but is absent for terP-CTFE. Beyond the contribution of the crystalline phase, the oriented amorphous fraction and crystalline defects (e.g., taut-tie molecules) also play significant roles in enhancing electrostriction. This mechanistic insight provides a valuable foundation for the rational design of next-generation RFE polymers with tunable properties through defect-engineering of their semicrystalline structures. 

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3. Synthesis of 9-borafluorene analogues featuring a three-dimensional 1,1′-bis( o -carborane) backbone

   https://doi.org/10.1039/c8cc10087j  

   Yruegas, Sam; Axtell, Jonathan C.; Kirlikovali, Kent O.; Spokoyny, Alexander M.; Martin, Caleb D. (January 2019, Chemical Communications)

   The synthesis of [1,1′-bis( o -carboranyl)]boranes was achieved through the deprotonation of 1,1′-bis( o -carborane) reagents followed by salt metathesis with ( i Pr) 2 NBCl 2 . X-ray crystallography confirms planar central BC 4 rings and Gutmann–Beckett studies reveal an increase in Lewis acidity at the boron center in comparison to their biphenyl congener, 9-borafluorene. 

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4. Catalyst‐Controlled 1,2‐ and 1,1‐Arylboration of α‐Alkyl Alkenyl Arenes

   https://doi.org/10.1002/anie.201812533  

   Bergmann, Allison M.; Dorn, Stanna K.; Smith, Kevin B.; Logan, Kaitlyn M.; Brown, M. Kevin (January 2019, Angewandte Chemie International Edition)

   Abstract Two methods are reported for the 1,2‐ and 1,1‐arylboration of α‐methyl vinyl arenes. In the case of 1,2‐arylboration, the formation of a quaternary center occurred through a rare cross‐coupling reaction of a tertiary organometallic complex. 1,1‐Arylboration was enabled by catalyst optimization and occurred through a β‐hydride elimination/reinsertion cascade. Enantioselective variants of both processes are presented as well as mechanistic investigations. 

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5. Discovery of an Inducible Toluene Monooxygenase that Co-oxidizes 1,4-Dioxane and 1,1-Dichloroethylene in Propanotrophic Azoarcus sp. DD4

   https://doi.org/10.1128/AEM.01163-20  

   Deng, Daiyong; Pham, Dung Ngoc; Li, Fei; Li, Mengyan (June 2020, Applied and Environmental Microbiology)

   Cometabolic degradation plays a prominent role in bioremediation of commingled groundwater contamination (e.g., chlorinated solvents and the solvent stabilizer 1,4-dioxane [dioxane]). In this study, we untangled the diversity and catalytic functions of multi-component monooxygenases in Azoarcus sp. DD4, a gram-negative propanotroph that is effective in degrading dioxane and 1,1-dichloroethylene (1,1-DCE). Using a combination of knockout mutagenesis and heterologous expression, a toluene monooxygenase (MO) encoded by the tmoABCDEF gene cluster was unequivocally proved as the key enzyme responsible for the cometabolism of both dioxane and 1,1-DCE. Interestingly, in addition to utilizing toluene as a primary substrate, this toluene MO can also oxidize propane into 1-propanol. Expression of this toluene MO in DD4 appears inducible by both substrates (toluene and propane) and their primary hydroxylation products (m-cresol, p-cresol, and 1-propanol). These findings coherently explain why DD4 can grow on propane and express toluene MO for active co-oxidation of dioxane and 1,1-DCE. Furthermore, upregulation of tmo transcription by 1-propanol underlines the implication potential of using 1-propanol as an alternative auxiliary substrate for DD4 bioaugmentation. The discovery of this toluene MO in DD4 and its degradation and induction versatility renders broad applications spanning from environmental remediation and water treatment to biocatalysis in green chemistry. Importance Toluene MOs have been well recognized given their robust abilities to degrade a variety of environmental pollutants. Built upon previous research efforts, this study ascertained the untapped capability of a toluene MO in DD4 for effective co-oxidation of dioxane and 1,1-DCE, two of the most prevailing yet challenging groundwater contaminants. This report also aligns the induction of a toluene MO with non-toxic and commercially accessible chemicals (e.g., propane and 1-propanol), extending its implication values in the field of environmental microbiology and beyond. 

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