Three Dimensional Quantitative Structure-Activity Relationships of Sulfonamides Binding Monoclonal Antibody by Comparative Molecular Field Analysis

The three-dimensional quantitative structure-activity relationship (3D-QSAR) model of sulfonamide analogs binding a monoclonal antibody (MabSMR) produced against sulfamerazine, was carried out by comparative molecular field analysis (CoMFA). The affinities of MabSMR, expressed as Log10IC50, for 17 sulfonamide analogs were determined by competitive fluorescence polarization immunoassay (FPIA). Removal of two outliers from the initial set of 17 sulfonamide analogs improved the predictability of the models. The 3D-QSAR model of 15 sulfonamides resulted in q2cv values of 0.600, and r2 values of 0.995, respectively. This novel study combining FPIA with CoMFA demonstrates that multidisciplinary research can be used as a useful tool to investigate antigen-antibody interactions and provide information required for design of novel haptens, which may result in new antibodies with properties already optimized by an antibody-based immunoassay

Investigation of Antigen-Antibody Interactions of Sulfonamides with a Monoclonal Antibody in a Fluorescence Polarization Immunoassay Using 3D-QSAR Models

A three-dimensional quantitative structure-activity relationship (3D-QSAR) model of sulfonamide analogs binding a monoclonal antibody (MAbSMR) produced against sulfamerazine was carried out by Distance Comparison (DISCOtech), comparative molecular field analysis (CoMFA), and comparative molecular similarity indices analysis (CoMSIA). The affinities of the MAbSMR, expressed as Log10IC50, for 17 sulfonamide analogs were determined by competitive fluorescence polarization immunoassay (FPIA). The results demonstrated that the proposed pharmacophore model containing two hydrogen-bond acceptors, two hydrogen-bond donors and two hydrophobic centers characterized the structural features of the sulfonamides necessary for MAbSMR binding. Removal of two outliers from the initial set of 17 sulfonamide analogs improved the predictability of the models. The 3D-QSAR models of 15 sulfonamides based on CoMFA and CoMSIA resulted in q2 cv values of 0.600 and 0.523, and r2 values of 0.995 and 0.994, respectively, which indicates that both methods have significant predictive capability. Connolly surface analysis, which mainly focused on steric force fields, was performed to complement the results from CoMFA and CoMSIA. This novel study combining FPIA with pharmacophore modeling demonstrates that multidisciplinary research is useful for investigating antigen-antibody interactions and also may provide information required for the design of new haptens

Experimental study on the dynamic behavior of rubber concrete under compression considering earthquake magnitude strain rate

To examine the compressive dynamic performance of rubber concrete, a uniaxial compression experimental study on rubber concrete was carried out using a hydraulic servo based on five different rubber substitution rates under eight different earthquake magnitude loading strain rates. The compressive failure modes and stress-strain curves of rubber concrete were obtained. By comparatively analyzing the mechanical characteristics of rubber concrete under different loading conditions, the following conclusions are drawn: with the increase in rubber substitution rate, the integrity of concrete upon compressive failure is gradually improved, and rubber particles exhibit an evident modification effect on cement mortar at the concrete interface. Under the influence of loading strain rate, the patterns of compressive failure mode of rubber concrete with different substitution rates are similar to that of ordinary concrete. Under the same loading strain rate, with the increase in rubber substitution rate, the compressive strength of rubber concrete gradually decreases while the plastic deformation capacity gradually increases. For the same rubber substitution rate, the compressive strength and elastic modulus of rubber concrete gradually increases with the increase in loading strain rate. The increase in rubber substitution rate gradually reduces the increasing amplitude of compressive strength and elastic modulus of rubber concrete under the influence of loading strain rate. Meanwhile, an equation was proposed to describe the coupling effect of rubber substitution rate and strain rate on the compressive strength dynamic increase factor of rubber concrete, and the underlying stress mechanism was further discussed. These results have significance in promoting the application of rubber concrete in engineering practice

The dynamic evolution of multipoint interplanetary coronal mass ejections observed with BepiColombo, Tianwen-1, and MAVEN

We present two multipoint interplanetary coronal mass ejections (ICMEs) detected by the Tianwen-1 and Mars Atmosphere and Volatile Evolution spacecraft at Mars and the BepiColombo (0.56 au ∼0.67 au) upstream of Mars from 2021 December 5 to 31. This is the first time that BepiColombo is used as an upstream solar wind monitor ahead of Mars and that Tianwen-1 is used to investigate the magnetic field characteristics of ICMEs at Mars. The Heliospheric Upwind Extrapolation time model was used to connect the multiple in situ observations and the coronagraph observations from STEREO/SECCHI and SOHO/LASCO. The first fast coronal mass ejection event (∼761.2 km s−1), which erupted on December 4, impacted Mars centrally and grazed BepiColombo by its western flank. The ambient slow solar wind decelerated the west flank of the ICME, implying that the ICME event was significantly distorted by the solar wind structure. The second slow ICME event (∼390.7 km s−1) underwent an acceleration from its eruption to a distance within 0.69 au and then traveled with the constant velocity of the ambient solar wind. These findings highlight the importance of background solar wind in determining the interplanetary evolution and global morphology of ICMEs up to Mars distance. Observations from multiple locations are invaluable for space weather studies at Mars and merit more exploration in the future

Rethinking Sesquiterpenoids: A Widespread Hormone in Animals

The sesquiterpenoid hormone juvenile hormone (JH) controls development, reproduction, and metamorphosis in insects, and has long been thought to be confined to the Insecta. While it remains true that juvenile hormone is specifically synthesized in insects, other types or forms of sesquiterpenoids have also been discovered in distantly related animals, such as the jellyfish. Here, we combine the latest literature and annotate the sesquiterpenoid biosynthetic pathway genes in different animal genomes. We hypothesize that the sesquiterpenoid hormonal system is an ancestral system established in an animal ancestor and remains widespread in many animals. Different animal lineages have adapted different enzymatic routes from a common pathway, with cnidarians producing farnesoic acid (FA); non-insect protostomes and non-vertebrate deuterostomes such as cephalochordate and echinoderm synthesizing FA and methyl farnesoate (MF); and insects producing FA, MF, and JH. Our hypothesis revolutionizes the current view on the sesquiterpenoids in the metazoans, and forms a foundation for a re-investigation of the roles of this important and yet neglected type of hormone in different animals

Application of Grafting Method in Resistance Identification of Sweet Potato Virus Disease and Resistance Evaluation of Elite Sweet Potato [<i>Ipomoea batatas</i> (L.) Lam] Varieties

Sweet potato virus disease (SPVD) is one of the main virus diseases in sweet potato [Ipomoea batatas (L.) Lam] that seriously affects the yield of sweet potato. Therefore, the establishment of a simple, rapid and effective method to detect SPVD is of great significance for the early warning and prevention of this disease. In this study, the experiment was carried out in two years to compare the grafting method and side grafting method for three sweet potato varieties, and the optimal grafting method was selected. After grafting with seedlings infected with SPVD, the symptomatic diagnosis and serological detection were performed in 86 host varieties, and the differences in SPVD resistance were determined by fluorescence quantitative PCR (qRT-PCR) and nitrocellulose membrane enzyme-linked immunosorbent assay (NCM-ELISA). The results showed that the survival rate of grafting by insertion method was significantly higher than that by side grafting method, and the disease resistance of different varieties to sweet potato virus disease was tested. The detection method established in this study can provide theoretical basis for identification and screening of resistant sweet potato varieties

Multistep Lithiation of Tin Sulfide: An Investigation Using <i>in Situ</i> Electron Microscopy

Two-dimensional (2D) metal sulfides have been widely explored as promising electrodes for lithium-ion batteries since their two-dimensional layered structure allows lithium ions to intercalate between layers. For tin disulfide, the lithiation process proceeds <i>via</i> a sequence of three different types of reactions: intercalation, conversion, and alloying, but the full scenario of reaction dynamics remains nebulous. Here, we investigate the dynamical process of the multistep reactions using <i>in situ</i> electron microscopy and discover the formation of an intermediate rock-salt phase with the disordering of Li and Sn cations after initial 2D intercalation. The disordered cations occupy all the octahedral sites and block the channels for intercalation, which alter the reaction pathways during further lithiation. Our first-principles calculations of the nonequilibrium lithiation of SnS₂ corroborate the energetic preference of the disordered rock-salt structure over known layered polymorphs. The <i>in situ</i> observations and calculations suggest a two-phase reaction nature for intercalation, disordering, and following conversion reactions. In addition, <i>in situ</i> delithiation observation confirms that the alloying reaction is reversible, while the conversion reaction is not, which is consistent with the <i>ex situ</i> analysis. This work reveals the full lithiation characteristic of SnS₂ and sheds light on the understanding of complex multistep reactions in 2D materials

Multistep Lithiation of Tin Sulfide: An Investigation Using <i>in Situ</i> Electron Microscopy

Two-dimensional (2D) metal sulfides have been widely explored as promising electrodes for lithium-ion batteries since their two-dimensional layered structure allows lithium ions to intercalate between layers. For tin disulfide, the lithiation process proceeds <i>via</i> a sequence of three different types of reactions: intercalation, conversion, and alloying, but the full scenario of reaction dynamics remains nebulous. Here, we investigate the dynamical process of the multistep reactions using <i>in situ</i> electron microscopy and discover the formation of an intermediate rock-salt phase with the disordering of Li and Sn cations after initial 2D intercalation. The disordered cations occupy all the octahedral sites and block the channels for intercalation, which alter the reaction pathways during further lithiation. Our first-principles calculations of the nonequilibrium lithiation of SnS₂ corroborate the energetic preference of the disordered rock-salt structure over known layered polymorphs. The <i>in situ</i> observations and calculations suggest a two-phase reaction nature for intercalation, disordering, and following conversion reactions. In addition, <i>in situ</i> delithiation observation confirms that the alloying reaction is reversible, while the conversion reaction is not, which is consistent with the <i>ex situ</i> analysis. This work reveals the full lithiation characteristic of SnS₂ and sheds light on the understanding of complex multistep reactions in 2D materials

Multistep Lithiation of Tin Sulfide: An Investigation Using <i>in Situ</i> Electron Microscopy

Two-dimensional (2D) metal sulfides have been widely explored as promising electrodes for lithium-ion batteries since their two-dimensional layered structure allows lithium ions to intercalate between layers. For tin disulfide, the lithiation process proceeds <i>via</i> a sequence of three different types of reactions: intercalation, conversion, and alloying, but the full scenario of reaction dynamics remains nebulous. Here, we investigate the dynamical process of the multistep reactions using <i>in situ</i> electron microscopy and discover the formation of an intermediate rock-salt phase with the disordering of Li and Sn cations after initial 2D intercalation. The disordered cations occupy all the octahedral sites and block the channels for intercalation, which alter the reaction pathways during further lithiation. Our first-principles calculations of the nonequilibrium lithiation of SnS₂ corroborate the energetic preference of the disordered rock-salt structure over known layered polymorphs. The <i>in situ</i> observations and calculations suggest a two-phase reaction nature for intercalation, disordering, and following conversion reactions. In addition, <i>in situ</i> delithiation observation confirms that the alloying reaction is reversible, while the conversion reaction is not, which is consistent with the <i>ex situ</i> analysis. This work reveals the full lithiation characteristic of SnS₂ and sheds light on the understanding of complex multistep reactions in 2D materials