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1. Fitting fangs in a finite face: A novel fang accommodation strategy in a 280‐million‐year‐old ray‐finned fish

   https://doi.org/10.1111/joa.13798  

   Figueroa, Rodrigo T.; Andrews, James V. (March 2023, Journal of Anatomy)

   Abstract Though Paleozoic ray‐finned fishes are considered to be morphologically conservative, we report a novel mode of fang accommodation (i.e., the fitting of fangs inside the jaw) in the Permian actinopterygian †Brazilichthys macrognathus, whereby the teeth of the lower jaw insert into fenestrae of the upper jaw. To better understand how fishes have accommodated lower jaw fangs through geologic time, we synthesize the multitude of ways living and extinct osteichthyans have housed large mandibular dentition. While the precise structure of fang accommodation seen in †Brazilichthyshas not been reported in any other osteichthyans, alternate strategies of upper jaw fenestration to fit mandibular fangs are present in some extant ray‐finned fishes—the needlejawsAcestrorhynchusand the gars of the genusLepisosteus. Notably, out of our survey, only the two aforementioned neopterygians bear upper jaw fenestration for the accommodation of mandibular fangs. We implicate the kinetic jaws of neopterygians in this trend, whereby large mandibular fangs are more easily fit between the multitude of upper jaw and palatal bones. The restricted space available in early osteichthyan jaws may have led to a proliferation of novel ways to accommodate large dentition. We recommend a greater survey of Paleozoic actinopterygian jaw morphology, in light of these results and other recent reevaluations of jaw structure in early fossil ray‐fins. 

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2. New monstersaur specimens from the Kaiparowits Formation of Utah reveal unexpected richness of large-bodied lizards in Late Cretaceous North America

   https://doi.org/10.1098/rsos.250435  

   Woolley, C Henrik; Sertich, Joseph_J W; Melstrom, Keegan M; Irmis, Randall B; Smith, Nathan D (June 2025, Royal Society Open Science)

   Monstersauria (Squamata, Anguimorpha) fossils are present in most Upper Cretaceous sedimentary basins in western North America, but despite almost a century of collection, their record remains extremely fragmentary. Here, we describe new material belonging to large-bodied monstersaurs, including a new taxon,Bolg amondolgen. et sp. nov., based on a fragmentary associated skeleton and co-occurring specimens from the middle unit of the upper Campanian Kaiparowits Formation of Grand Staircase–Escalante National Monument in southern Utah, USA. Phylogenetic analyses recoverB. amondolwithin Monstersauria, with two unique anatomical features: fused osteoderms on the jugal and the presence of autotomy septa on the distal caudal vertebrae. Critically,B. amondolis morphologically distinct from the problematic Late Cretaceous North American monstersaurPalaeosaniwa canadensis, whereas co-occurring monstersaur vertebrae and parietals from the Kaiparowits Formation (cf.P. canadensis) highlight a pressing need for a reassessment of this important, widespread taxon. These results offer new evidence that at least three lineages of distinct, large-bodied monstersaurian lizard were present on the palaeolandmass of Laramidia during the Campanian Stage. Importantly,B. amondolrepresents the most complete squamate recovered from late Campanian southern Laramidia and reveals key anatomical characteristics for future identification of isolated lizard fossil elements. 

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3. An arrayed optofluidic system for three-dimensional (3D) focal control via electrowetting

   https://doi.org/10.1364/OE.489508  

   Lee, Yeonwoo; Lee, Cheng-Hsun; Park, Sung-Yong (January 2023, Optics Express)

   A new lens capability for three-dimensional (3D) focal control is presented using an optofluidic system consisting ofn × narrayed liquid prisms. Each prism module contains two immiscible liquids in a rectangular cuvette. Using the electrowetting effect, the shape of the fluidic interface can be rapidly adjusted to create its straight profile with the prism’s apex angle. Consequently, an incoming ray is steered at the tilted interface due to the refractive index difference between two liquids. To achieve 3D focal control, individual prisms in the arrayed system are simultaneously modulated, allowing incoming light rays to be spatially manipulated and converged on a focal point located atP_focal(f_x,f_y,f_z) in 3D space. Analytical studies were conducted to precisely predict the prism operation required for 3D focal control. Using three liquid prisms positioned on thex-,y-, and 45°-diagonal axes, we experimentally demonstrated 3D focal tunability of the arrayed optofluidic system, achieving focal tuning along lateral, longitudinal, and axial directions as wide as 0 ≤ f_x ≤ 30 mm, 0 ≤ f_y ≤ 30 mm, and 500 mm ≤ f_z ≤ ∞. This focal tunability of the arrayed system allows for 3D control of the lens’s focusing power, which could not be attained by solid-type optics without the use of bulky and complex mechanical moving components. This innovative lens capability for 3D focal control has potential applications in eye-movement tracking for smart displays, autofocusing of smartphone cameras, or solar tracking for smart photovoltaic systems. 

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4. Membership Testing for Semantic Regular Expressions

   https://doi.org/10.1145/3729300  

   Huang, Yifei; Amini, Matin; Le_Glaunec, Alexis; Mamouras, Konstantinos; Raghothaman, Mukund (June 2025, Proceedings of the ACM on Programming Languages)

   This paper is about semantic regular expressions (SemREs). This is a concept that was recently proposed by Smore (Chen et al. 2023) in which classical regular expressions are extended with a primitive to query external oracles such as databases and large language models (LLMs). SemREs can be used to identify lines of text containing references to semantic concepts such as cities, celebrities, political entities, etc. The focus in their paper was on automatically synthesizing semantic regular expressions from positive and negative examples. In this paper, we study themembership testing problem. First, we present a two-pass NFA-based algorithm to determine whether a stringwmatches a SemRErinO(|r|²|w|²+ |r| |w|³) time, assuming the oracle responds to each query in unit time. In common situations, where oracle queries are not nested, we show that this procedure runs inO(|r|²|w|²) time. Experiments with a prototype implementation of this algorithm validate our theoretical analysis, and show that the procedure massively outperforms a dynamic programming-based baseline, and incurs a ≈ 2 × overhead over the time needed for interaction with the oracle. Second, we establish connections between SemRE membership testing and the triangle finding problem from graph theory, which suggest that developing algorithms which are simultaneously practical and asymptotically faster might be challenging. Furthermore, algorithms for classical regular expressions primarily aim to optimize their time and memory consumption. In contrast, an important consideration in our setting is to minimize the cost of invoking the oracle. We demonstrate an Ω(|w|²) lower bound on the number of oracle queries necessary to make this determination. 

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5. Reproducible 3D bioprinting of Streptococcus mutans to create model oral biofilms

   https://doi.org/10.1128/spectrum.00935-25  

   Rocha, Guilherme Roncari; Benoit, Danielle_S W; Meyer, Anne S (November 2025, Microbiology Spectrum)

   Kolodkin-Gal, Ilana (Ed.)

   ABSTRACT Novel approaches are needed to study relationships between oral biofilm strains, enable three-dimensional oral biofilm deposition, and hasten the rigor and pace of basic and translational biofilm studies. Previously, 3D-bioprinters were leveraged to deposit spatially patterned biofilms onto sugar-rich agar surfaces to study how the underlying spatial organization of various microbes impacts biofilm persistence and virulence. Herein, we have developed a new method to adapt this process from limited, soft agar surfaces to biomimetic solid substrates submerged in aqueous solutions for studying oral biofilmsin vitro. Streptococcus mutansUA159 was used to compare standardin vitrobiofilm development with our new 3D-printed bio-ink hydrogels on hydroxyapatite disks, which mimic tooth surfaces. Biofilms formed using the bio-ink methodology showed minimal quantitative differences in virulence factors, including environmental pH, biomass, and cell density, compared to biofilms formed using the standardin vitromethodology. The bio-ink technique resulted in higher exopolysaccharide deposition, a key virulence factor for biofilm cohesion and protection, as well as more homogeneous spatial distribution of bacterial microcolonies. Our newly developed technique produces 3D-printable model biofilms that match the virulence benchmarks of the standard method, opening possibilities to print biofilms onto any substrate and a new way to study multidimensional biofilm dynamics.IMPORTANCEDental caries is the most common oral disease caused by biofilms in humans with cost limitations. Changes in the human diet have increased the exposure to sugar-rich processed food, increasing the incidence and severity of dental caries and creating greater rationale for understanding biofilm deposition, microbial interactions, and maintenance of quiescence of the oral microbiota. Recent 3D-printing techniques have been leveraged to develop the first model biofilms, providing spatial control over microbe deposition and enabling unprecedented investigation of the impact of cell-cell interactions and spatial organizationupon biofilm persistence, sensitivity to drugs, and virulence. Here, we have developed new methods to extend bioprinting to oral biofilms using cariogenicStreptococcus mutans. Our technique is an attempt to establish an alternative method for oral biofilm formationin vitrothat uses 3D-printing tools, preserving the virulence of standardin vitrobiofilms while amplifying the availability and versatility of methods for understanding the microbiome. 

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