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Abstract Quantifying the configuration space and the Gibbs measure of thermally disordered condensed matter systems has been a long-standing problem. The challenge is to avoid the Gibbs paradox, which forbids any ordering or labeling of the atoms. Our key observation is that the lattice of a thermally disordered condensed matter system, in either solid, liquid, or gas phase, can be fully reconstructed from the Voronoi cells of the atoms alone, even if these Voronoi cells are disassembled and randomly scrambled. In the example of the crystalline phase of silicon, the statistics of the Voronoi cells reveals the existence of four, and only four, large facets that are present with probability one for all temperatures up to the solid–liquid melting line. These four largest facets, which separate nearest-neighboring atoms, can be also be used to reconstruct the lattice of the crystal. Hence, their collection supplies the optimal representation of the configuration of the crystal. We conjecture that the existence of Voronoi facets that, despite their large thermal fluctuations, survive with probability one up to the melting temperature, is the fundamental signature of the crystalline solid phase and therefore key to quantifying the Gibbs measure over the entire solid phase. 

Abstract Transcription factor nuclear factor-kappa B (NF-κB) and many upstream signaling components have been identified in a diversity of holozoan taxa, including unicellular holozoans (eg Filasterea and Choanoflagellata) and the metazoan phyla Porifera (sponges), Placozoa, and Cnidaria (eg jellyfishes, sea anemones, corals, and hydra). Herein, we review recent progress made toward characterizing the structure, regulation, activity, and biological functions of NF-κB proteins found in these taxa. We also provide an updated phylogenetic sampling of NF-κB orthologs highlighting their different domain configurations among holozoans, as well as a method for comparing the computationally predicted three-dimensional structures of NF-κB dimers and relating these structures to their amino acid similarities and DNA-binding specificities. This synthesis reveals new insights regarding the evolutionarily conserved and variable domain-dependent activities and regulation of holozoan NF-κBs. Further, we provide an overview of the roles of NF-κB in pathogen responses, stress responses, symbiosis, and development, with a focus on recent findings from sponges and cnidarians. This curation of a growing body of knowledge highlights both conserved and divergent roles of NF-κB in foundational biological processes. Finally, we suggest priorities for future research on the evolution of NF-κB structure and function. Overall, investigations of NF-κB in diverse holozoan taxa will continue to provide information about the origins of this important and pervasive transcriptional regulator and will also contribute to an understanding of the responses of sentinel species to the modern-day stresses associated with changing environmental conditions and novel pathogen-based diseases. 

We report the observation and analysis of a new electronic transition in gas-phase vanadium hydride (VH), identified as the C′5Δ–X5Δ (1,0) band with an origin at 14,015 cm− 1 (714 nm). The spectrum was recorded by laser excitation spectroscopy, with laser-induced fluorescence detected to the X5Δ (v =1) level. Dispersed fluorescence measurements enabled a detailed characterization of the vibrationally excited ground state, yielding a vibrational interval of ΔG1/2 = 1606.6(2) cm− 1 . Despite the presence of significant local perturbations—particularly in the Ω =0 and 1 spin components of the C′5Δ state—a full rotational analysis of the spectrum using a Hund’s case (a) Hamiltonian was achieved. Spectroscopic constants including rotational, spin–orbit, spin–rotation, and Λ-doubling parameters are reported for both the new C′5Δ state and the X5Δ (v = 1) level. Additionally, we observed a small local perturbation in the X5Δ₁ (v =1) level near J =9, attributed to homogeneous spin–orbit and heterogeneous L-uncoupling interactions with the previously analyzed A5Π (v =0) state. An X5Δ ~ A5Π coupled Hamiltonian was used to model this perturbation and yielded interaction parameters roughly consistent with semi-empirical estimates. This work represents only the second analyzed spectroscopic transition of gas-phase VH. 

Atomic force microscopy‐based single‐molecule force spectroscopy (SMFS) experiments require stable and reproducible functionalization of cantilevers and surfaces. Conventional silane‐based methods suffer from poor stability, drastically hindering their reproducibility and performance. Here, we present an ethanol‐based aminopropyl‐silatrane functionalization protocol that achieves superior performance in a similar process timeframe. In particular, combining this approach with bacterial adhesin coupling, we demonstrated a significant twofold improvement in the fraction of attempted SMFS experiments yielding usable single‐molecule data. The method can be generally applied to silicon‐nitride and glass cantilevers and surfaces, including mechanically modified cantilevers optimized for fast time response, low stiffness, and low drift. Furthermore, we demonstrate a simple and cost‐efficient method to clean these functionalized cantilevers using common solvents and a benchtop UV‐ozone cleaner, allowing for refunctionalization and prolonged cantilever lifespans. Together, this allows for a reliable, reusable, and versatile functionalization protocol for high‐quality SMFS experiments.