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摘要： High magnetic fields provide a direct route to probe the anisotropies that govern spin dynamics in layered magnets. Using the SU(3) bond–operator framework for spin-1 systems, we derive analytic expressions for the magnon spectrum and the critical fields delimiting the field-induced ordered phase. We show that the upper critical field $h_{2c}$ carries a simple and quantitative fingerprint of both exchange anisotropy and single-ion symmetry breaking, enabling high-field experiments to serve as sensitive probes of microscopic anisotropy. We further map how these anisotropies, together with interlayer coupling, control the extent and location of the magnon Bose–Einstein condensation dome. Our results provide experimentally accessible criteria for identifying symmetry-breaking mechanisms in real spin-1 materials.

关键词： HipHop pharmacophore   Molecular docking   Molecular dynamics   Natural products   S1PR1 agonist   Virtual screening  

摘要： Sphingosine-1-phosphate receptor 1 (S1PR1), a member of the G protein-coupled receptor (GPCR) family, is a crucial therapeutic target for various diseases. Activation of S1PR1 has been recognized as an effective therapeutic strategy for multiple sclerosis (MS), inflammatory bowel disease (IBD), and psoriasis. Natural products (NPs) serve as a rich source of bioactive compounds for drug discovery. Here, we aimed to discover novel S1PR1 agonists from NPs via multi-level virtual screening (VS). Using a validated HipHop pharmacophore model, we screened a database containing 54,642 NPs, followed by molecular docking. Based on binding mode analysis, four candidate S1PR1 agonists (NPC323626, NPC264112, NPC469907, and NPC22192) were selected. Subsequent molecular dynamics (MD) simulations and binding free energy calculations confirmed the stability of the receptor-ligand complexes and their binding affinities. Among the four candidates, NPC469907 exhibited the strongest binding affinity for S1PR1, with a value of −58.08 ± 0.13 kJ/mol. Furthermore, hydrogen bonds formed between NPC469907 and Glu121 of S1PR1 were found to be essential for receptor activation. Quantum mechanical calculations further revealed that the phenyl-ring-attached hydrogen site in NPC469907 could be modified without compromising its ability to activate S1PR1. The analysis of Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) indicated that NPC469907 possessed favorable pharmacokinetic properties and low toxicity. In conclusion, our study identified NPC469907 as a promising natural S1PR1 agonist and established an effective VS strategy for the discovery of novel S1PR1 agonists.

关键词： Iron   Nitroxyl   Cluster   TEMPO   Oxide  

摘要：

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  Near homoleptic nitroxyl complexes.
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  [Na(ABNO)]₆(THF)₄, a pseudo hexamer of stacked cubes.
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  Deoxgenation products.
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  Unique hexairon(III) clusters.

关键词： Porcine reproductive and respiratory syndrome virus   Modified live vaccine   Efficacy   Pig   Experimental challenge   Highly virulent   Rosalia strain  

摘要： In 2020, atypical outbreaks of porcine reproductive and respiratory syndrome virus type 1 strain (PRRSV-1) were reported in northeastern Spain, characterized by high abortion rates, severe respiratory signs, and elevated mortality in affected nurseries. Sequencing analyses identified a highly virulent PRRSV-1.1 strain (Rosalia). This study evaluated the efficacy of a commercial live attenuated PRRSV-1 vaccine against this strain. Seventy PRRSV-naïve, 3-week-of-age piglets were randomly assigned to vaccinated (intradermal) and non-vaccinated groups. Five weeks post-vaccination, all piglets were intranasally challenged. Clinical signs, mortality, and weight gain were monitored for 28 days post-challenge; dpch. Viraemia, nasal shedding, tissue viral loads, lung lesions, and serological response were evaluated. Following challenge, 80% of the non-vaccinated piglets died within the first 22 days, compared to only 8.8% in the vaccinated group (p < 0.0001). Vaccinated animals showed significantly lower clinical scores, greater weight gain, and reduced lung lesions, with a relative decrease of 57.66% interstitial pneumonia and 77.67% lung area affected by bronchopneumonia. Viral loads in serum (3, 7, 14, and 17 dpch) and nasal secretions (10 and 14 dpch) were significantly lower in vaccinated animals, with fewer positive samples. Lung and tonsil viral loads were also significantly reduced. All vaccinated piglets seroconverted before challenge, and PRRSV-specific antibodies were detected in all animals by day 14 pch. Neutralizing antibody titres were significantly higher in vaccinated animals following challenge. These findings support the use of vaccination to confer significant protection against clinical disease and virological replication caused by the Spanish highly virulent PRRSV-1.1 (Rosalia) strain.

关键词： Aggregation-induced emission (AIE)   Fluorescent probe   Polyarylpyrrolidone   Lead ion detection  

摘要：

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  Develop two novel carboxyl-functionalized polyarylpyrrolidone AIE probes for selective Pb²⁺ detection.
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  Model an unusual 1:2 binding stoichiometry and elucidate the mechanism via DFT calculations.
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  Demonstrate practical applicability through the fabrication of test strips for on-site monitoring.

关键词： Dendrobium nobile Lindl. Alkaloids   Caenorhabditis elegans   Stress resistance   DAF-16   Skn-1  

摘要： This study aimed to explore the anti-aging effects and mechanisms of Dendrobium nobile Lindl. Alkaloids (DNLA) on Caenorhabditis elegans (C. elegans).

关键词： Interfacial materials   Supramolecular solids   Electronics materials  

摘要：

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  Compliant supramolecular solid fills air gaps at soft electronic interfaces.
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  Aqueous self-assembly of hydrazide and phosphonic acid yields a clay-like solid.
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  Permittivity reaches around 9.4 with proton-driven transport in the network.
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  Thermal conductivity is two to three times higher than silicone elastomer.
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  Capacitance triples when the solid replaces an air gap between flat electrodes.

关键词： 2-design   Flag-transitive   Automorphism group   Almost simple group  

摘要： Let $\mathcal{D}=(\mathcal{P},\mathcal{B})$ be a 2-$(v,k,\lambda )$ design admitting a flag-transitive automorphism group G with $\gcd (v-1,k-1)=3$ or 4. We showed in [28, Theorems 1.2 and 1.3] that G is point-primitive and of affine or almost simple type, except when $\mathcal{D}$ is a unique 2-$(25,4,12)$ or 2-$(25,4,18)$

关键词： Symmetric design   Group action   Abelian group   Point-line geometry  

摘要： A design is called t-pyramidal when it has an automorphism group which fixes t points and acts sharply transitively on the remaining points. We determine all symmetric (2k-1, 2k-1, 2k-2)-designs which are (2k-1-1)-pyramidal over abelian groups. (c) 2026 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Nonrecurrent orbit   Hausdorff Dimension   Hausdorff Dimension   (-beta)-Transformation  

摘要： We investigate the size of the set of beta > 1 for which the orbits of 1 are nonrecurrent under the (-beta)-transformation T-beta. We prove that the set of beta > 1 with sup(n >= 1)T(-beta)(2n-1)(1) < 1 has Lebesgue measure 0. By constructing fractal sets in a neighborhood of an algebraic number beta > 1, we show that the set {beta is an element of (1,root 5 + 1/ 2 sup(n >= 1)T(-beta)(n)(1) < 1} is of full Hausdorff dimension. The result of this paper significantly extends the related known result of beta-transformation and that of T-beta for beta >= root 5+1/ 2.