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The Paleobiology Database (PBDB; https://paleobiodb.org) consists of geographically and temporally explicit, taxonomically identified fossil occurrence data. The taxonomy utilized by the PBDB is not static, but is instead dynamically generated using an algorithm applied to separately managed taxonomic authority and opinion data. The PBDB owes its existence to many individuals, some of whom have entered more than 1.26 million fossil occurrences and over 570,000 taxonomic opinions, and some of whom have developed and maintained supporting infrastructure and analysis tools. Here, we provide an overview of the data model currently used by the PBDB and then briefly describe how this model is exposed via an Application Programming Interface (API). Our objective is to outline how PBDB data can now be accessed within individual scientific workflows, used to develop independently managed educational and scientific applications, and accessed to forge dynamic, near real-time connections to other data resources.

Semiconducting polymers have garnered considerable attention from researchers, as these polymers are potentially applicable to flexible/stretchable organic electronics. However, although the adhesiveness of these materials on substrates is an important characteristic, it has rarely been investigated. Herein, we synthesized and characterized a novel block copolymer, poly(3-hexylthiophene)-b-poly(vinyl catechol) (P3HT-b-PVC), with improved adhesion properties. P3HT-b-PVC was successfully synthesized via a copper-catalyzed azide–alkyne cycloaddition reaction between chain-end-functionalized P3HT with an alkyne group (P3HT-Alkyne) and chain-end-functionalized poly(3,4-di-tert-butyldimethylsilyloxystyrene) with an azide group (PSVC-Azide), followed by deprotection of tert-butyldimethylsilyloxy groups from the PSVC-Azide segment. Tape test results showed that the adhesion property of the P3HT-b-PVC film was considerably better than that of the corresponding P3HT film. Furthermore, despite the presence of an insulating PVC block in P3HT-b-PVC, the P3HT-b-PVC thin film exhibited a hole mobility of 1.1 × 10−5 cm2V−1s−1, which was comparable to that of the corresponding P3HT thin film (1.8 × 10−5 cm2V−1s−1). To the best of our knowledge, this is the first study to elucidate the primitive adhesion properties and charge mobility of P3HT-based block copolymers. The proposed synthetic approach may be extended to develop various block copolymers with other π-conjugated polymer segments, providing new avenues for various applications that require highly-adhesive materials.A novel block copolymer, poly(3-hexylthiophene)-b-poly(vinyl catechol) (P3HT-b-PVC) was successfully synthesized via a Click reaction between chain-endfunctionalized P3HT with an alkyne group (P3HT-Alkyne) and chain-end-functionalized poly(3,4-di-tert-butyldimethylsilyloxystyrene) with an azide group (PSVC-Azide), followed by deprotection of tert-butyldimethylsilyloxy groups from the PSVC-Azide segment. Tape test results showed that the adhesion property of the P3HT-b-PVC film was considerably better than that of the corresponding P3HT film. Furthermore, despite the presence of an insulating PVC block in P3HT-b-PVC, the P3HT-b-PVC thin film exhibited a hole mobility comparable to that of the corresponding P3HT thin film.

Herein, we report the preparation of polyacrylate-based vitrimer-like elastomers with dynamic bond-exchangeable cross-links. The component polymer is a poly(ethyl acrylate)-based copolymer that bears pyridine groups randomly and was cross-linked by a quaternization reaction with dibromo cross-linkers (dibromo hexane). In this system, bond exchange is induced via trans-N-alkylation at high temperatures, which is revealed by elongational creep and stress-relaxation tests. Some useful functions of the present material, such as reprocessability, recyclability, and unique solubility, were also demonstrated.A preparation of polyacrylate-based vitrimer-like elastomers with dynamic bond-exchangeable cross-links is demonstrated. The component polymer is a poly(ethyl acrylate)-based copolymer bearing pyridine groups randomly, which was cross-linked by a quaternization reaction of pyridine groups with dibromo cross-linkers (dibromo hexane). The bond exchange is induced via trans-N-alkylation of quaternized pyridines at high temperatures, which is revealed by temperature-ramp FT-IR, elongational creep, and stress-relaxation tests. Some useful functions of the present material, such as reprocessability, thermal and chemical recyclability, are provided due to the bond exchange nature.

In response to the problem of microplastics, polyesters are attracting great attention due to their degradability in underwater environments. We recently demonstrated that the hydrolysis of linear polyglycolide (PGA) in a fiber state strongly depends on segmental dynamics in aqueous phases. This finding implies that the degradation of PGA can be controlled by tuning the segmental dynamics in water. Our choice of fiber geometry was based on its relatively large surface area-to-volume ratio. Herein, we examined the effects of the addition of a hyperbranched polymer (HBP) with a polyester skeleton and with many terminal hydroxy groups on the degradability characteristics of fiber mats. Dynamic mechanical analysis revealed that HBP acted as a plasticizer, especially in underwater environments. The weight loss of the PGA fiber mats was accelerated with increasing HBP content. In addition, structural analyses confirmed that crystal degradation had occurred and that hydrolysis-cleaved chains had crystallized. Considering that the structural changes in the PGA crystals depended on the feed amount of HBP, we claimed that HBP promoted PGA degradation in both the amorphous and crystalline phases. We believe that our simple strategy for accelerating the degradation of polyesters can provide suggestions for solving issues with microplastics.The effects of the addition of a hyperbranched polymer (HBP) on the degradability characteristics of linear polyglycolide (PGA) fiber mats. It was revealed that HBP acted as a plasticizer, especially in underwater environments. The weight loss of the PGA fiber mats was accelerated with increasing HBP content. Considering that the structural changes in the PGA crystals depended on the feed amount of HBP, it was claimed that HBP promoted PGA degradation in both the amorphous and crystalline phases.

Using X-ray absorption spectroscopy (XAS) with linearly polarized soft X-rays, we investigated the local conformation of poly(methyl methacrylate) (PMMA) adsorbed to a SiOx/Si(111) surface. The preedge intensity of the O K-edge XAS for PMMA, originating from the O 1s → π* transition at a C=O group in the side chain, was stronger for vertically polarized incident X-rays than for horizontally polarized ones. Conversely, the XAS intensity originating from the O 1s → σ* transition showed the opposite trend. These findings suggest that the C=O group in the side chain of PMMA exhibited preferential orientation rather than an amorphous arrangement. To gain further insights, we conducted a depth profile analysis of the local conformation of PMMA using XAS combined with an argon gas cluster ion beam (GCIB). GCIB-XAS analysis revealed that the orientation of the C=O group in the side chain of PMMA differs between the region from the SiOx interface to a distance on the order of 1 nanometer and the bulk PMMA region.The aggregation states from the interface to the bulk of the adhesive/adherend is a key to unraveling adhesion at the molecular level. We applied X-ray absorption spectroscopy (XAS) in combination with an Ar gas cluster ion beam (Ar GCIB) to poly(methyl methacrylate) (PMMA) films adsorbed onto a SiOx/Si(111) surface. GCIB-XAS analysis revealed that the orientation of the C=O group in the side chain of PMMA differs between the region from the SiOx interface to a distance on the order of 1 nanometer and the bulk PMMA region.

We have investigated the self-assembly kinetics of silica nanoparticles (SNPs) into the polymer-like structure by time-resolved small-angle X-ray scattering (SAXS). The analysis of the SAXS data with a kinetic model revealed that the SNPs undergo self-assembly in a process akin to the step-growth polymerization of bifunctional monomers. This study offers a facile strategy to construct polymer-like structures from isotropic spherical nanoparticles.

Fiber batteries have been developed as ideal energy storage devices for wearable electronics due to their superior miniaturization, deformability, and flexibility compared with conventional bulk and thin-film batteries. However, currently reported fiber batteries use materials that are intrinsically rigid or have limited flexibility (e.g., metal, carbon materials, and elastomers), which potentially cause physical irritation and internal injury upon close contact with biological tissues. Therefore, it is necessary to design soft materials for ultrasoft fiber batteries that are mechanically matched with biological tissues. Here, ultrasoft coaxial fiber-structured aqueous lithium-ion batteries based on an all-hydrogel design are reported. The all-hydrogel fiber aqueous lithium-ion batteries exhibited a low Young’s modulus of 445 kPa, which perfectly matched that of biological tissue. They also showed a high specific discharge capacity of 84.8 mAh·g−1 at a current density of 0.5 A·g−1 and superior performance in terms of cycling behavior and rate capacity. Furthermore, these fiber batteries maintained stable electrochemical performance while undergoing different complex deformations. The present work demonstrates a paradigm for designing ultrasoft fiber batteries and also provides insight into the development of soft wearable electronics.The first ultrasoft aqueous lithium-ion batteries with coaxial fiber structures were fabricated with an all-hydrogel design. The all-hydrogel fiber aqueous Li-ion battery exhibited a high specific discharge capacity of 84.8 mAh·g−1 and superior cycling behavior and rate capacity performance. A low Young’s modulus (e.g., 445 kPa) for the battery was achieved by making it entirely from hydrogels, which ensured mechanical compatibility with biological tissues.

To increase the quality of life of dialysis patients while maintaining economic efficiency, the concept of a wearable artificial kidney was proposed and designed approximately two decades ago. However, the primary challenge in the development of a wearable artificial kidney is the adequate removal of urea from dialysate due to the chemical inertness of urea under physiological conditions. Herein, a hollow polystyrene nanoparticle with sulfonic acid groups, named H-CPS-SO3H, was synthesized that could efficiently adsorb urea. H-CPS-SO3H was produced in three steps. First, a core-shell polystyrene nanoparticle with a linear core and cross-linked shell was prepared using modified emulsion polymerization. Second, the core-shell nanoparticles were treated with DMF to create hollow nanoparticles. Finally, the hollow nanoparticles were subjected to sulfuric acid treatment to produce H-CPS-SO3H, which was confirmed by both TEM and FTIR analysis. The urea adsorption capacity and kinetics of the as-synthesized H-CPS-SO3H were evaluated in a 30 mM urea aqueous solution. The results indicated that H-CPS-SO3H had a urea absorption capacity of up to 1 mmol/g, which was achieved after only two hours of adsorption at 37 °C. These findings demonstrated the high adsorption capacity and favorable adsorption kinetics of H-CPS-SO3H. Additionally, the adsorption capacity first increased and then slightly decreased with decreasing pH or increasing solution volume, while the adsorption capacity sharply decreased with increasing ionic strength. The results suggest that the prepared H-CPS-SO3H has promising application potential in the field of wearable artificial kidney devices.Achieving a wearable artificial kidney hinges on overcoming the critical challenge of developing efficient urea adsorption materials for dialysate regeneration. An acidic hollow polystyrene nanoparticle was synthesized by modified emulsion polymerization, DMF etching and sulfuric acid treatment sequentially. The nanoparticles had a urea absorption capacity of up to 1 mmol/g after two hours of adsorption in a 30 mM urea aqueous solution at 37 °C. Additionally, the adsorption capacity dramatically increased with increasing urea concentration, while sharply decreased with increasing ionic strength.

Ediacaran fronds are key components of terminal-Proterozoic ecosystems. They represent one of the most widespread and common body forms ranging across all major Ediacaran fossil localities and time slices postdating the Gaskiers glaciation, but uncertainty over their phylogenetic affinities has led to uncertainty over issues of homology and functional morphology between and within organisms displaying this ecomorphology. Here we present the first large-scale, multigroup cladistic analysis of Ediacaran organisms, sampling 20 ingroup taxa with previously asserted affinities to the Arboreomorpha, Erniettomorpha, and Rangeomorpha. Using a newly derived morphological character matrix that incorporates multiple axes of potential phylogenetically informative data, including architectural, developmental, and structural qualities, we seek to illuminate the evolutionary history of these organisms. We find strong support for existing classification schema and devise apomorphy-based definitions for each of the three frondose clades examined here. Through a rigorous cladistic framework it is possible to discern the pattern of evolution within and between these clades, including the identification of homoplasies and functional constraints. This work both validates earlier studies of Ediacaran groups and accentuates instances in which previous assumptions of their natural history are uninformative.

Research on polymer surfaces has shown that the mobilities of polymer chains, which affect the aggregation state and thus the physical properties of the material, differ between the surface and bulk. However, the mobilities of the surface polymers have not been fully characterized. Therefore, we propose a time-resolved method for evaluating surface mobility. This measurement scheme is called grazing incidence diffracted X-ray blinking (GI-DXB) and can be used to evaluate the molecular motions occurring at polymer surfaces by continuously measuring X-ray diffraction patterns near the total reflection angle over small time periods. In this study, the crystallized polymer poly{2-(perfluorooctyl)ethyl acrylate}(PC8FA) was measured. The decay constants, which are indexes of molecular motions, were calculated to be 3.98 × 10−3 s−1 for the fluoroalkyl groups in the side chains observed along the in-plane direction and 3.36 × 10−3 s−1 for the lamellar structure observed along the out-of-plane direction when 2000 diffraction profiles of 500 ms were recorded and the incident angle was 0.07°. In contrast, transmission DXB indicated decay constants of 2.63 × 10−3 s−1 for the side chains and 2.87 × 10−3 s−1 for the lamellar structures. These results suggested that the PC8FA surface is mobile, because a larger decay constant indicates a higher mobility. GI-DXB can be used to measure surface dynamics. The authors contend that GI-DXB is a highly versatile tool because it allows the evaluation of local motions with a laboratory X-ray system, and these motions cannot be detected by conventional surface analyses. This measurement scheme may facilitate the development of high-performance polymers and discovery of new physical properties.The grazing incidence diffracted X-ray blinking was proposed to evaluate the molecular motions occurring at polymer surfaces by measuring X-ray diffraction patterns near the total reflection angle over small time periods. When the crystallized polymer poly{2-(perfluorooctyl)ethyl acrylate}(PC8FA) film was measured, the results of the decay constants, which are indexes of molecular motions, suggested that the PC8FA surface is mobile compared to the bulk.