bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single‐Crystal‐to‐Single‐Crystal Synthesis of a Polymer in Two Distinct Topologies
Authors: Pathan Javed R. , Balan Haripriya , Das Kaustav , Reddy C. Malla , Sureshan Kana M. 
Published: January 2025

AbstractA squaramide‐based monomer, designed for topochemical azide‐alkyne cycloaddition (TAAC) polymerization, crystallizes as two polymorphs, M1 and M2, both having crystal packing suitable for topochemical polymerization. The hydrogen‐bonding between squaramide units bias the molecular organization in both the polymorphs. 3D packing of H‐bonded stacks of monomer lead to juxtaposition of azide and alkyne units of adjacent molecules in a transition‐state‐like arrangement for their regiospecific cycloaddition reaction. The monomers are arranged as supramolecular sheets and supramolecular helices in polymorph M1 and M2 respectively. Both the polymorphs undergo slow and spontaneous regiospecific TAAC polymerization at room temperature, but react quickly at higher temperatures, resulting in 1,4‐traizolyl‐linked polymer, with distinct mechanical responses. Upon heating, single crystals of polymorph M1 show expansion followed by contraction without any permanent dimensional change, whereas crystals of polymorph M2 undergo splitting. At moderate temperatures, both the polymorphs undergo single‐crystal‐to‐single‐crystal (SCSC) polymerization, resulting in two polymer‐polymorphs with distinct topologies that can be studied at atomic resolution by single‐crystal X‐ray crystallography. The polymorph M1 reacts to polymer P1 with β‐sheet‐like topology, and polymorph M2 reacts to polymer P2 having polymer chains of helical conformation. Nanoindentation experiments with crystals of these polymers revealed their distinct mechanical properties.
Steady State Free Precession NMR without Fourier Transform: Redefining the Capabilities of 19F NMR as a Discovery Tool
Authors: Gauthier Jeremy R. , Kock Flavio , Downey Katelyn , Moraes Tiago , Almeida Luísa Souza , Muir Derek C. G. , Letcher Robert J. , Colnago Luiz , Krishnamurthy Krish , Mabury Scott , Simpson Andre J. 
Published: January 2025

AbstractThe 2024 Zurich perfluorinated compounds (PFCs) summit reiterated the urgent need for non‐selective analytical approaches for PFC detection. 19F NMR holds great potential, however, sensitivity limitations lead to long analysis times and/or the possibility of not detecting low concentration species. Steady State Free Precession (SSFP) NMR collects the signal in a steady state regime, allowing 100’s of acquisitions in the timespan of a single traditional NMR scan. Unfortunately, data truncation from SSFP leads to artifacts and spectral broadening with Fourier transform, hindering interpretation. When non‐Fourier based time‐domain analysis is used, namely, complete reduction to amplitude frequency tables (CRAFT), limitations of SSFP are eliminated while sensitivity gains are retained. This work introduces the combined approach, then applies it for the measurement of PFCs in environmental and biological samples. In all cases, the approach reduces analysis time from many hours to minutes and/or greatly increases the range of compounds detected. For example, when PFOA was spiked into human blood, the detection limit improved ~50‐fold vs standard NMR, while in a standard mixture, the approach detected compounds missed by LC‐MS/MS. The technique can be adapted to any nucleus providing a facile approach to reduce experiment time and improve sensitivity of NMR in general.
Optogenetic control of transgene expression in Marchantia polymorpha
Authors: Lindström Battle Anya Lillemor , Sweetlove Lee James 
Published: January 2025

AbstractPremiseThe model liverwort Marchantia polymorpha is an emerging testbed species for plant metabolic engineering but lacks well‐characterized inducible promoters, which are necessary to minimize biochemical and physiological disruption when over‐accumulating target products. Here, we demonstrate the functionality of the light‐inducible plant‐usable light‐switch elements (PULSE) optogenetic system in Marchantia and exemplify its use through the light‐inducible overproduction of the bioplastic poly‐3‐hydroxybutyrate (PHB).MethodsThe PULSE system was used to drive expression of luciferase as a reporter and characterize its induction in transgenic M. polymorpha. Additionally, PULSE was used to drive expression of the PHB biosynthetic pathway; the accumulation of PHB under light‐inducible control was compared to constitutive overexpression.ResultsPULSE was fully functional and minimally leaky in M. polymorpha. The presence of the PULSE construct, even in the absence of induction, resulted in a developmental phenotype. Constitutive and inducible expression resulted in similar PHB accumulation levels.DiscussionPHB biosynthesis in plants is known to adversely affect plant health, but placing its production under optogenetic control alleviated negative effects on biomass accumulation in some instances. The work presented here represents a significant expansion of the toolbox for the metabolic engineering of M. polymorpha.
A Simple and Effective Method for the Cryopreservation of Quillwort Spores
Authors: Cavalheiro‐Filho Sérgio L. , Campos Naiara V. , Gripp Anderson R. , Jordão Laís B. , Cavalcante Allysson B. , Esteves Francisco A. , Martins Rodrigo L. , Gestinari Lísia M. S. 
Published: January 2025

ABSTRACTQuillworts are highly threatened worldwide and many Isoëtes species have been suffering population decreases. Isoëtes cangae is a lycophyte endemic from a single Amazon lake that has been challenging due to climate change and deforestation of the Amazon rainforest. The development of strategies for ex situ conservation of lycophyte germplasm is urgent to prevent biodiversity losses. Spores of I. cangae were obtained from specimens collected in situ. Samples were submitted to three different moisture conditions: hydrated, air‐dry desiccation and drying in silica gel. Desiccated samples were stored in an ultrafreezer (−80°C) or liquid nitrogen (−196°C) and the hydrated spores at room temperature. The spore viability was evaluated through spore germination (G) and sporeling emergence (SE) indices after 30, 90, 180 and 275 days of storage. The growth of emerged sporophytes was evaluated after 3 months. Desiccated–cryopreserved spores had high G% and SE%, even after 275 days of storage, and did not differ from hydrated spores. Hydrated spores had higher daily emergence and a longer time to maximum sporophyte emergence than desiccated spores, but not in all storage periods. Sporophytes that emerged from hydrated and desiccated spores had a similar development. Both desiccated methods and temperatures of storage maintained spore viability high. The methodologies tested in this study are novel for the genus and represent a significant step towards the ex situ conservation of quillworts.
Catalytic Reinforcement in Hybrid Imidazole Functionalized Cobalt Phthalocyanine and Ketjenblack for Boosted Hydrogen Evolution
Authors: Chikkabasur Kumbara Ashwini , Kousar Naseem , Koodlur Sannegowda Lokesh 
Published: January 2025

AbstractHydrogen energy is widely regarded as one of the cleanest forms of green energy due to its bio‐friendly nature. However, its commercialization is restricted by many issues. One of the major issues is related to high production cost, which can be overcome by designing of effective catalysts through simple, innovative and cost‐effective approach for efficient green hydrogen production. In this study, we report the synthesis of an eco‐friendly, affordable, and highly redox‐active tetra‐imidazole functionalized cobalt phthalocyanine (TImCoPc) through a straightforward method. To ensure its purity and effectiveness as an electrocatalyst for the hydrogen evolution reaction (HER) in 0.5 M H₂SO₄, various analytical techniques are employed for its thorough characterization. The electrocatalytic performance and conductivity of TImCoPc is further enhanced by forming hybrid with highly conductive Ketjenblack (KB) in various ratios. Among the different ratios, the 3.5 : 1.5 (TImCoPc/KB) composite exhibited excellent HER performance, with an onset potential closer to that of Pt/C and an overpotential (η₁₀) of −108 mV, closely approaching the η₁₀ of Pt/C (−36 mV). Additionally, the optimized hybrid showed a lower Tafel slope of 44 mV/dec, higher turnover frequency of 3.66x10−10 mol s−1 cm−2 and mass activity of 4.121 A mg−1, with an excellent catalytic stability, thereby proving to be one of the superior electrocatalysts for HER in terms of cost, methodology, activity and efficiency. The observed enhancement in HER activity of the hybrid can be accounted to the synergistic effects that reduce the metal ion's d‐band center and improve π‐π interactions between the hybrid components. The composite also demonstrated an increased electrochemical active surface area. This work highlights the potential of the TImCoPc/KB (3.5 : 1.5) composite as a cost‐effective and efficient catalyst for sustainable hydrogen production.
Ce1‐xMnxVO4 with Improved Activity for Low‐Temperature Catalytic Reduction of NO with NH3
Authors: Wang Li , Wang Jun‐bo , Cheng He‐ping , Xu Hui , Wu Shi‐ni , Huang Fei , Chen Long , Ma Zhen 
Published: January 2025

AbstractNovel Ce1‐xMnxVO4 catalysts prepared via modified hydrothermal synthesis were used in selective catalytic reduction of NO using NH3 (NH3‐SCR). The Ce1‐xMnxVO4 catalysts displayed optimum NO removal efficiency at 250 °C. Physicochemical properties including crystal type, morphology, particle size, elemental composition, BET surface area, chemical bond, and valence state were studied by XRD, TEM, EDS, N2 adsorption‐desorption, Raman spectroscopy, and XPS. Specific properties such as reduction property and acid sites were studied by H2‐TPR and NH3‐TPD. The in‐situ DRIFTS results revealed that NH3‐SCR over Ce0.5Mn0.5VO4 follows the Eley‐Rideal mechanism. The experimental results showed that doped manganese replaces the Ce position in CeVO4. The Mn−O−Ce interaction may increase the contents of oxygen defects and Brønsted acid sites, thus leading to enhanced activity.
A non‐surgical method for subretinal delivery by trans‐scleral microneedle injection
Authors: Hejri Amir , Chrenek Micah A. , Goehring Nolan T. , Bowland Isabella I. , Noel Richard , Yan Jiong , Nickerson John M. , Prausnitz Mark R. 
Published: January 2025

AbstractNovel therapeutics have emerged for treating neurodegenerative eye diseases but are limited by non‐optimal methods of ocular administration. Subretinal injection is the preferred method of delivery for retinal gene and stem‐cell therapies, but its invasive and complex surgical procedure is a major limiting factor in clinical investigations and practice. Here, we engineered a novel trans‐scleral injection technique to safely administer to the subretinal space in a simple, non‐surgical, and minimally invasive procedure. Subretinal injection using this technique in rodents and rabbits took <1 min per injection and did not require a surgical microscope. Extensive safety examinations in rats showed that the injection technique reliably administered into the subretinal space with no incidence of retinal perforation, little or no choroidal bleeding, and no evidence of retinal toxicity. We further found that repeated subretinal injection in the same eye, in rats, was well tolerated. The developed technique may enable non‐surgical subretinal injection without vitrectomy, potentially increasing safety, efficacy, and access to ocular therapies.
Investigation of Pyrrole Analogues Inhibition on Main Protease by Spectroscopic Analysis, Molecular Docking, and Enzyme Activity
Authors: Wang Nuoya , Chen Leyao , Ye Wenjun , Yu Wenquan , Chang Xiaoyu , Wang Ruiyong 
Published: January 2025

ABSTRACTThe main protease (Mpro) is a cysteine enzyme and represents a vital target for antiviral drug screening. In this work, 25 pyrrole derivatives were synthesized and screened by enzyme activity experiments. Results indicate that six pyrrole derivatives can bind to Mpro and have an inhibitory effect on Mpro. The binding mode involves a static quenching process. Among them, 1d exhibits the highest binding affinity. The interactions between pyrrole derivatives and Mpro are investigated by spectra and molecular docking. The interaction between 1d and Mpro is spontaneous and enthalpy‐driven. Hydrogen bonding is identified as the primary binding force for 1d. Furthermore, nitro groups are important for the binding between pyrrole analogs and Mpro. This study elucidates the mechanism of interactions and provides direction and valuable insights for developing novel Mpro inhibitors.
Self‐Assembly of the Co‐Catalysts of a Dual Photoredox/Hydrogen Atom Transfer Catalytic Process: Curiosity or Opportunity?
Authors: Carré Victor , Vincent Jean‐Marc 
Published: January 2025

AbstractDual photoredox/Hydrogen atom transfer (HAT) catalytic processes are an emerging class of redox neutral catalytic processes which allow the functionalization of inert C(sp3)−H bonds. A key step of such processes is a single electron transfer (SET) between the photoredox catalyst (PC) excited state and the HAT catalyst, which is typically a chloride or a bromide ion. Until recently, the SET has only been considered as an intermolecular process. Considering recent works dealing with the photooxidation of halides into halogen atoms occurring within Ru‐based PC ⋅ halides complexes, as well as recent results from our group describing a prototypical example of an organic PC ⋅ chloride complex applied to the photoalkylation of C(sp3)−H bonds, this concept article aims at discussing the potential benefits and drawbacks of self‐assembling the co‐catalysts employed in dual photoredox/HAT catalytic processes.
The influence of lightning on insect and fungal dynamics in a lowland tropical forest
Authors: Lawhorn Kane A. , Richards Jeannine H. , Gora Evan M. , Burchfield Jeffrey C. , Bitzer Phillip M. , Gutierrez Cesar , Yanoviak Stephen P. 
Published: January 2025

AbstractLightning strikes are a common source of disturbance in tropical forests, and a typical strike generates large quantities of dead wood. Lightning‐damaged trees are a consistent resource for tropical saproxylic (i.e., dead wood‐dependent) organisms, but patterns of consumer colonization and succession following lightning strikes are not known. Here, we documented the occurrence of four common consumer taxa spanning multiple trophic levels—beetles, Azteca ants, termites, and fungi—in lightning strike sites and nearby undamaged control sites over time in a lowland forest of Panama. Beetle abundance was 10 times higher in lightning strike sites than in paired control sites, and beetle assemblages were compositionally distinct. Those in strike sites were initially dominated by bark and ambrosia beetles (Curculionidae: Platypodinae, Scolytinae); bark and ambrosia beetles, and predaceous taxa increased in abundance relatively synchronously. Beetle activity and fungal fruiting bodies, respectively, were 3.8 and 12.2 times more likely to be observed in lightning‐damaged trees in strike sites versus undamaged trees in paired control sites, whereas the occurrence probabilities of Azteca ants and termites were similar between damaged trees in lightning strike sites and undamaged trees in control sites. Tree size also was important; larger dead trees in strike sites were more likely to support beetles, termites, and fungal fruiting bodies, and larger trees—regardless of mortality status—were more likely to host Azteca. Beetle presence was associated with higher rates of subsequent fungal presence, providing some evidence of beetle‐associated priority effects on colonization patterns. These results suggest that lightning plays a key role in supporting tropical insect and fungal consumers by providing localized patches of suitable habitat. Any climate‐driven changes in lightning frequency in tropical forests will likely affect a broad suite of consumer organisms, potentially altering ecosystem‐level processes.
Assembly Accuracy Analysis Method Based on Multi‐Stage Linearized Contact
Authors: Tang Wenbin , Li Yadong , Yan Tong , Zhang Min 
Published: January 2025

ABSTRACTPrecision improvement in mechanical manufacturing faces challenges due to nonlinear effects impacting assembly accuracy analysis models. An assembly accuracy analysis method based on multi‐stage linearized contact is proposed to address this issue. A model of part surface asperities considering morphological errors is established using the linear superposition of discrete cosine transform (DCT) kernel functions and the assembly interface is simplified. By employing homogeneous coordinate transformation (HCT), the prediction of the part's pose during the assembly process with the rigid body assumption is achieved. The elastic contact process is divided into multiple stages according to the order of the asperity participating in the contact and further subdivided into several linear processes by adding nodes at each stage. The relationship between the assembly load and the deformation amount is established based on the related theories of contact mechanics and the geometric relationship between the assembly interfaces, thus enabling the prediction of the part's pose during the assembly process. Taking a multi‐way hydraulic valve as an object, by comparing the accuracy of pose prediction of the algorithm before and after adding nodes, it is proved that the proposed method can significantly improve the precision of assembly accuracy analysis.
Extension of High‐Order Lattice Boltzmann Flux Solver for Simulation of Three‐Dimensional Compressible Flows
Authors: Qin Jian , Wu Jie , Qin Qiushuo 
Published: January 2025

ABSTRACTIn this paper, a high‐order lattice Boltzmann flux solver (LBFS) based on flux reconstruction (FR) is presented for simulating the three‐dimensional compressible flows. Unlike the original LBFS employing finite volume methods, the current method (FR‐LBFS) can achieve arbitrary high‐order accuracy with a compact stencil. High‐order schemes based on finite volume methods often compromise parallel efficiency and complicate boundary treatment. In contrast, LBFS incorporates physical effects in calculating inviscid fluxes, providing superior shock‐capturing capabilities over traditional approximate Riemann solvers. The present method combines the strengths of both FR and LBFS, yielding enhanced performance. Specifically, there is limited analysis of compact high‐order LBFS in simulations of three‐dimensional compressible flows. Several benchmark test cases are employed to validate the superiority of the current method, and the results show good agreement with established literature values. The shock tube problem and inviscid Taylor‐Green vortex demonstrate the shock‐capturing capability and low‐dissipation characteristics of FR‐LBFS. Meanwhile, the decaying homogeneous isotropic turbulent flow and the flow around a triangular airfoil highlight the accuracy of the current method in turbulence simulation. The obtained numerical results demonstrate that the proposed method holds considerable promise for applications in simulations of compressible and turbulent flows.
Glia Modulates Immune Responses in the Retina Through Distinct MHC Pathways
Authors: Intonti Simona , Kokona Despina , Zinkernagel Martin S. , Enzmann Volker , Stein Jens V. , Conedera Federica M. 
Published: January 2025

ABSTRACTGlia antigen‐presenting cells (APCs) are pivotal regulators of immune surveillance within the retina, maintaining tissue homeostasis and promptly responding to insults. However, the intricate mechanisms underlying their local coordination and activation remain unclear. Our study integrates an animal model of retinal injury, retrospective analysis of human retinas, and in vitro experiments to gain insights into the crucial role of antigen presentation in neuroimmunology during retinal degeneration (RD), uncovering the involvement of various glial cells, notably Müller glia and microglia. Glial cells act as sentinels, detecting antigens released during degeneration and interacting with T‐cells via MHC molecules, which are essential for immune responses. Microglia function as APCs via the MHC Class II pathway, upregulating key molecules such as Csf1r and cytokines. In contrast, Müller cells act through the MHC Class I pathway, exhibiting upregulated antigen processing genes and promoting a CD8+ T‐cell response. Distinct cytokine signaling pathways, including TNF‐α and IFN Type I, contribute to the immune balance. Human retinal specimens corroborate these findings, demonstrating glial activation and MHC expression correlating with degenerative changes. In vitro assays also confirmed differential T‐cell migration responses to activated microglia and Müller cells, highlighting their role in shaping the immune milieu within the retina. In summary, our study emphasizes the involvement of retinal glial cells in modulating the immune response after insults to the retinal parenchyma. Unraveling the intricacies of glia‐mediated antigen presentation in RD is essential for developing precise therapeutic interventions for retinal pathologies.
Clinical Characteristics During and After COVID‐19 Infection Among Healthcare Workers During the First Wave of Omicron in Chongqing, China
Authors: Tang Haoling , Chen Zhiwei , Huang Tianquan , Yu Pingping , Tang Qiao , Qiu Yue , Xue Yunling , Tang Jing , Cai Nan , Ren Hong , Peng Mingli , Hu Peng 
Published: January 2025

ABSTRACTBackgroundRevealing the clinical manifestations and associations of COVID‐19 before and after negative transition remains an area of significant uncertainty. The aim of this study is to investigate the clinical characteristics observed during and after Omicron infection among a specific population, namely healthcare workers (HCWs).MethodsFrom November 4, 2022, to January 15, 2023, HCWs in our hospital were enrolled to document clinical symptoms, prevention, and treatment for COVID‐19 using a structured questionnaire.ResultsA total of 1101 HCWs were included, with SARS‐CoV‐2 infection detected in 78.20% (861/1101) during the observation period. The median duration for nucleic acid conversion was 8 days. Forty‐three symptoms were identified during SARS‐CoV‐2 infection (11 symptoms per individual). The common symptoms were fever, cough, headache, phlegm production, and fatigue (60.67%–83.29%). These symptoms can be further categorized into five groups: fever type, upper respiratory tract type, influenza type, digestive system type, and systemic type—all showing complex and diverse patterns. Following SARS‐CoV‐2 infection, a total of 19 symptoms were recorded including four newly emerged ones: reduced lung capacity, memory loss, lethargy, and inattention. Importantly, we observed a significant association between gastrointestinal symptoms during the nucleic acid positive phase and subsequent neuropsychiatric manifestations after negative conversion. Interestingly, females experiencing menstruation or pregnancy exhibited a higher risk of infection, while inhaled vaccines and thymosin demonstrated a protective effect against SARS‐CoV‐2 infection.ConclusionsThe clinical manifestations observed in HCWs during and after Omicron infection displayed intricate patterns, shedding new light on the complex interplay between SARS‐CoV‐2 and humans.