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In this paper, all molecules (1,2-ethanediol, ethanol, methoxymethanol, dimethyl ether, and dimethyl peroxide) predicted to be produced as a result of C–C, C–O, or O–O bond formation between methanol molecules induced by laser-driven shock wave were detected and identified by gas chromatography-mass spectroscopy. In this process, the ultrahigh pressure resulting from the shock wave is considered to reduce the interatomic distance between molecules to mechanically create a new chemical bond. Methoxymethanol production was further verified by infrared absorption spectroscopy of the laser-irradiated methanol concentrated by vacuum distillation. In the concentrated sample, polyoxymethylene hemiformals, which are presumably produced by the polymerization of methoxymethanol, were also found. [ABSTRACT FROM AUTHOR]

Separation and identification of molecules and biomolecules such as nucleic acids, proteins, and polysaccharides from complex fluids are known to be important due to unmet needs in various applications. Generally, many different separation techniques, including chromatography, electrophoresis, and magnetophoresis, have been developed to identify the target molecules precisely. However, these techniques are expensive and time consuming. "Lab‐on‐a‐chip" systems with low cost per device, quick analysis capabilities, and minimal sample consumption seem to be ideal candidates for separating particles, cells, blood samples, and molecules. From this perspective, different microfluidic‐based techniques have been extensively developed in the past two decades to separate samples with different origins. In this review, "lab‐on‐a‐chip" methods by passive, active, and hybrid approaches for the separation of biomolecules developed in the past decade are comprehensively discussed. Due to the wide variety in the field, it will be impossible to cover every facet of the subject. Therefore, this review paper covers passive and active methods generally used for biomolecule separation. Then, an investigation of the combined sophisticated methods is highlighted. The spotlight also will be shined on the elegance of separation successes in recent years, and the remainder of the article explores how these permit the development of novel techniques. [ABSTRACT FROM AUTHOR]

The piperazine moiety is often found in drugs or in bioactive molecules. This widespread presence is due to different possible roles depending on the position in the molecule and on the therapeutic class, but it also depends on the chemical reactivity of piperazine-based synthons, which facilitate its insertion into the molecule. In this paper, we take into consideration the piperazine-containing drugs approved by the Food and Drug Administration between January 2011 and June 2023, and the synthetic methodologies used to prepare the compounds in the discovery and process chemistry are reviewed. [ABSTRACT FROM AUTHOR]

Shellac is a natural resin composed of a complex mixture of hydroxy aliphatic acids, primarily aleuritic acid (AA), and sesquiterpenoid acids such as jalaric acid (JA). The paper puts forth valuable information on the polymerization mechanism considering AA and JA using Gaussian 16.0 software. Computations of energy, thermochemical values, and molecular orbital coefficients have been done using both Hartree-Fock (HF) and Density Functional Theory (DFT) to establish the mechanism. Global reactivity parameter study revealed that monomers of the shellac are hard whereas the polymer units are soft. HOMO-LUMO, ESP and theoretical FTIR results are coherent with the previously reported works for the prediction of possible polymeric species present in the shellac along with their thermodynamic stability. This is the first attempt to predict the linkages in shellac resin. This study helps understand the mechanism of formation of lac polymer and also highlights the associated properties of shellac. [ABSTRACT FROM AUTHOR]

As living standards advance, an escalating emphasis is placed on health, particularly in relation to prevalent chronic metabolic disorders. It is necessary to explore safe and effective functional foods or drugs. Fu brick tea (FBT) is a kind of dark tea fermented by fungi. The extracts are rich in compounds that can effectively relieve metabolic diseases such as hyperglycemia and hyperlipidemia, protect the liver, improve human immunity, enhance antioxidant activity, and regulate intestinal flora. This paper summarizes the biological activities and mechanisms of the extracts, polysaccharides, and small molecular compounds of FBT, which provides a certain theoretical basis for the rational, systematic, comprehensive development and utilization of the FBT resources. It is expected to develop and apply these active substances in health care products and natural medicines and provide more beneficial and diversified FBT products for human beings. [ABSTRACT FROM AUTHOR]

Designing 3D molecules with high binding affinity for specific protein targets is crucial in drug design. One challenge is that the atomic interaction between molecules and proteins in 3D space has to be taken into account. However, the existing target-aware methods solely model the joint distribution between the molecules and proteins, disregarding the binding affinities between them, which leads to limited performance. In this paper, we propose an explainable diffusion model to generate molecules that can be bound to a given protein target with high affinity. Our method explicitly incorporates the chemical knowledge of protein–ligand binding affinity into the diffusion model, and uses the knowledge to guide the denoising process towards the direction of high binding affinity. Specifically, an SE(3)-invariant expert network is developed to fit the Vina scoring functions and jointly trained with the denoising network, while the domain knowledge is distilled and conveyed from Vina functions to the expert network. An effective guidance is proposed on both continuous atom coordinates and discrete atom types by taking advantages of the gradient of the expert network. Experiments on the benchmark CrossDocked2020 demonstrate the superiority of our method. Additionally, an atom-level explanation of the generated molecules is provided, and the connections with the domain knowledge are established. [ABSTRACT FROM AUTHOR]

In past years, optical lattices have been demonstrated as an excellent platform for making, understanding, and controlling quantum matters at nonlinear and fundamental quantum levels. Shrinking experimental observations include matter-wave gap solitons created in ultracold quantum degenerate gases, such as Bose–Einstein condensates with repulsive interaction. In this paper, we theoretically and numerically study the formation of one-dimensional gap soliton molecules and clusters in ultracold coherent atom ensembles under electromagnetically induced transparency conditions and trapped by an optical lattice. In numerics, both linear stability analysis and direct perturbed simulations are combined to identify the stability and instability of the localized gap modes, stressing the wide stability region within the first finite gap. The results predicted here may be confirmed in ultracold atom experiments, providing detailed insight into the higher-order localized gap modes of ultracold bosonic atoms under the quantum coherent effect called electromagnetically induced transparency. [ABSTRACT FROM AUTHOR]

This paper focuses the study of nonlinear absorption (NLA) features of anthraquinone dye namely, acid blue 129 with different polar solvents including ethanol, methanol, acetone, 1-proponal and DMSO. The acid blue 129 dye in polar solvents is characterized by UV–Visible absorption and fluorescence study. The NLA measurements of acid blue 129 dye is examined via open aperture (OA) Z-scan method employing at 650 nm wavelength. The OA Z-scan curve of the experimental dye exhibits both saturable absorption (SA) and reveres saturable absorption (RSA) signature, which results from negative and positive NLA coefficient (β). The order of ground and excited state absorption cross-section is measured to be 10˗22 m2 and 10˗18 m2, respectively and proved the existence of RSA in acid blue 129 dye. The order of NLA coefficient and imaginary component of the third-order nonlinear susceptibility of acid blue 129 dye in polar solvents is calculated to be 10˗3 cm/W and 10˗5 esu, respectively. The multi-parameter scale viz., Kamlet-Abboud-Taft is used to measure the influence of solvent parameters on solute molecule. The results from the experiments suggest that the acid blue 129 is a suitable candidate for nonlinear optical (NLO) applications. [ABSTRACT FROM AUTHOR]

Dichroism experiments with 150 fs time resolution on anthracene in benzyl alcohol are presented as a function of viscosity from 14.4 cP (274 K) to 2.7 cP (329 K). These measurements test a qualitative prediction of the viscoelastic picture of liquid dynamics, specifically that earlier “inertial” dynamics have a viscosity independent rate, whereas later “diffusive” dynamics have a rate directly proportional to viscosity. This paper focuses on two components of the dichroism decay that are assigned to rotational motion. A third component is assigned to electronic-state solvation and is analyzed in a companion paper [J. Chem. Phys. 115, 4231 (2001)]. The longest component is due to rotational diffusion and is very well described by a hydrodynamic model with slip boundary conditions. A fast decay component in the subpicosecond region is found and shown to have a viscosity-independent rate. It is assigned to inertial rotation by comparison to the computer simulations of Jas et al. [J. Chem. Phys. 107, 8800 (1997)]. Inertial rotation extends out to at least 1 ps, longer than the range commonly assumed for inertial dynamics. Over much of this range, the inertial rotation is not free-rotor-like, but is strongly modified by interaction with the solvent. The inertial rotation also accounts for the “missing” anisotropy found when the rotational diffusion fits are extrapolated to zero time. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A variety of interstellar complex organic molecules (COMs) have been detected in various physical conditions. However, in the protostellar and protoplanetary environments, their complex kinematics make line profiles blend together and the line strength of weak lines weaker. In this paper, we utilize the principal component analysis technique to develop a filtering method that can extract COM spectra from the main kinematic component associated with COM emission and increase the signal-to-noise ratio (S/N) of spectra. This filtering method corrects non-Gaussian line profiles caused by the kinematics. For this development, we adopt the ALMA BAND 6 spectral survey data of V883 Ori, an eruptive young star with a Keplerian disk. A filter was, first, created using 34 strong and well-isolated COM lines and then applied to the entire spectral range of the data set. The first principal component (PC1) describes the most common emission structure of the selected lines, which is confined within the water sublimation radius (∼0.″3) in the Keplerian disk of V883 Ori. Using this PC1 filter, we extracted high-S/N kinematics-corrected spectra of V883 Ori over the entire spectral coverage of ∼50 GHz. The PC1-filtering method reduces the noise by a factor of ∼2 compared to the average spectra over the COM emission region. One important advantage of this PC1-filtering method over the previously developed matched-filtering method is the ability to preserve the original integrated intensities of COM lines. [ABSTRACT FROM AUTHOR]

This paper discusses the state of advancement in the development of spectroscopic methods based on the use of mid (proper) infrared radiation in the context of applications in various fields of science and technology. The authors drew attention to the most important solutions specific to both spectroscopy itself (ATR technique) and chemometric data processing tools (PCA and PLS models). The objective of the current paper is to collect and consistently present information on various aspects of FT-IR spectroscopy, which is not only a well-known and well-established method but is also continuously developing. The innovative aspect of the current review is to show FT-IR's great versatility that allows its applications to solve and explain issues from both the scientific domain (e.g., hydrogen bonds) and practical ones (e.g., technological processes, medicine, environmental protection, and food analysis). Particular attention was paid to the issue of hydrogen bonds as key non-covalent interactions, conditioning the existence of living matter and determining the number of physicochemical properties of various materials. Since the role of FT-IR spectroscopy in the field of hydrogen bond research has great significance, a historical outline of the most important qualitative and quantitative hydrogen bond theories is provided. In addition, research on selected unconventional spectral effects resulting from the substitution of protons with deuterons in hydrogen bridges is presented. The state-of-the-art and originality of the current review are that it presents a combination of uses of FT-IR spectroscopy to explain the way molecules vibrate and the effects of those vibrations on macroscopic properties, hence practical applications of given substances. [ABSTRACT FROM AUTHOR]

Oxyonium phosphobetaines are recently discovered molecules with a unique ! O–P–O–N+ bond system, which makes them useful and versatile intermediates for the synthesis of phosphates and their derivatives. In this paper, the preliminary data on the application of these compounds in nucleoside phosphorylation were presented. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Sea buckthorn (SBT) (Hippophae rhamnoides L.), a shrub rich with a huge variety of vitamins, antioxidants and other biologically active constituents with pharmacological and cosmaceutical applications. OBJECTIVE: The current review aims to compile the recent reported data on the ethnobotany, phytochemistry, biological activities and cosmaceutical uses of SBT plant from different regions of the world. METHODS: A wide-ranging inquiry on SBT was done electronically on the basis of articles and abstracts published in peer-reviewed journals, issued in conference proceedings, government reports, books, Master's and Ph.D. theses, etc. The research was carried out in different international scientific databases like Academic Search, Biological Abstracts, BIOSIS, BioOne Previews, CabDirect, Cochrane Library, Pubmed/Medline, GeoRef, Google Scholar, JSTOR, Journal Citation Reports, Mendeley, Publons, Researchgate, Scopus, SciELO, Springer Link, Science Direct, Web of Science, Taylor and Francis with particular keywords. RESULTS: A total of 185 published papers were assessed through the search approach and 162 papers were included published on SBT. It was evident from the literature search that the uses of SBT as traditional medicine so far against nearly 50 health related complications in more than 18 regions of the world are still a common practice where the decoction of leaves and juice/paste from berries/fruits of SBT were the common administration modes. Data on the phytochemical profile of SBT revealed more than 50 diverse reported groups of compounds with remarkable antioxidant activity against reactive oxygen species (ROS) using DPPH, FRAP and ABTS as common methods. Moreover to-date, the reported antimicrobial activity of SBT uncovered that the extracts from SBT were examined in contradiction of 32 strains of bacteria and 15 strains of fungus with significant inhibitory actions against the bacterial and fungal strains. The SBT extracts actions reported so far on different viral disease categories displayed active inhibition of the growth of nearly 15 different viral strains. The reported anticancer activity of compounds in SBT extracts to date evidenced remarkable results against more than 20 different cancer cell lines/types. Moreover, SBT oil containing fatty acids, tocopherols and carotenoids is effectively used with cosmetic applications for skin care. CONCLUSIONS: Conclusively, SBT is rich with several remarkable phytochemicals that may have diverse biological actions and for that reason reassure the use of decoctions and/or infusions of SBT as folk traditional medicine around the world. Conversely, it is essential to explore the molecular mechanisms of compounds responsible for biological activities of SBT and to advance in the research of clinical uses and development of SBT based therapeutic and cosmetic products. [ABSTRACT FROM AUTHOR]

In this paper, a 3D molecular dynamics (MD) simulation is performed to investigate the nanoindentation process, the most frequently used technique to measure mechanical properties such as hardness, of three Al/Mg intermetallic compounds, where Mg is the main element added to pure Al. To further improve the understanding of the mechanical response, in this study, we examine the hardness-strength data for three kinds of typical materials, including β -Al3Mg2 and γ - Al 1 2 Mg 1 7 and - Al 3 0 Mg 2 3 phases with different microstructures. In terms of the observed morphologies around the indentations, the influencing variables of the general link between strength and hardness are described. Accordingly, atomic simulations in this paper are performed under the same loading (2 1 × 1 0 1 0 s − 1 ) using a spherical diamond indenter. At both the - Al 3 0 Mg 2 3 and γ - Al 1 2 Mg 1 7 phases, we can see that the indenter generates a bigger deformation zone and a greater number of dislocations in the z direction. The simulation findings show that the microstructure has an impact on the shape of the deformation in each phase. After the deformation process, we get the depth-displacement (P – h) curves to describe the mechanical behavior of β -Al3Mg2, - Al 3 0 Mg 2 3 and γ - Al 1 2 Mg 1 7 phases. From the P – h curves, we got the radial distribution function, mechanical properties, such as micro hardness, Yield point and maximum load are determined and presented. According to the findings, the chemical composition of these phases has a considerable impact on their characteristics. These P – h curves obtained show a rapid increase in loading up to a maximum. The deformation behavior of −Al3Mg2 and − Al 1 2 Mg 1 7 phases under nanoindentation is slightly identical, and they have also a high elasticity limit, the ability to endure deformation and the characteristic of being very ductile and malleable. While - Al 3 0 Mg 2 3 phase was shown to be brittle and weak under the same uniaxial nanoindentation loading compared to other phases, it was found that there is a good correlation between the previous simulated studies. [ABSTRACT FROM AUTHOR]

Heavy-atom alkaline earth monofluoride molecules are considered as prospective systems to study spatial parity or spatial parity and time-reversal symmetry violating effects such as the nuclear anapole moment or the electron electric dipole moment. A comprehensive and highly accurate theoretical study of the electronic structure properties and transition energies in such systems can simplify the preparation and interpretation of the experiments. However, almost no attempts to calculate quantum electrodynamics (QED) effects' contribution into characteristics of these neutral heavy-atom molecules have been performed. Recently, we have formulated and implemented such an approach to calculate QED contributions to transition energies of molecules [L. V. Skripnikov, J. Chem. Phys. 154, 201101 (2021)]. In this paper, we perform a benchmark theoretical study of the transition energies in the Ba+ cation and BaF molecule. The deviation of the calculated values from the experimental ones is of the order 10 cm−1 and is more than an order of magnitude better than the "chemical accuracy," 350 cm−1. The achievement of such an agreement has been provided, in particular, by the inclusion of the QED effects. The latter appeared to be not less important than the high-order correlation effects beyond the coupled cluster with single, double, and perturbative triple cluster amplitude level. We compare the role of QED effects for transition energies with heavier molecules—RaF and E120F, where E120 is the superheavy Z = 120 homolog of Ra. [ABSTRACT FROM AUTHOR]

Granular molecular crystals show a large variation in the orientation, length, shape, and cohesive interactions of interfaces when embedded in a polymer matrix. But the determination of the associated excess of free energy is not straightforward, especially due to the entropic contribution which is not negligible for molecular compounds. The surface free energy (SFE) is also important to predict crystal shapes and growth or to prove crucial insights into the mesoscale interfaces in the granular composites often with interfacial defects, voids, and pores. In this paper, we use Molecular Dynamics (MD) and assess and adapt two non-equilibrium methods, namely, non-equilibrium thermodynamic integration (NETI) and modified steered MD (SMD), to determine the SFE of various facets of a high-energy molecular crystal of interest: β-HMX. Starting with defect-free surfaces, both methods agree well with experiment concerning the most stable facets, whose energy is further lowered by a large entropic contribution. For some facets, surface creation (debonding process) and annihilation (bonding process) show fundamentally different paths, henceforth irreversible. Then, we discuss some sources of discrepancy between theoretical and experimental SFE, considering non-reversible dissipative events, surface roughness, and differences between various experimental techniques. These non-equilibrium methods can be applied to a wide range of molecular crystals and to study interface stability in polycrystals or with binding polymers, including the effects of various defects. [ABSTRACT FROM AUTHOR]

Supermolecule refers to two or more molecules that are bonded together by secondary bonds between molecules to form a multimolecular system at the level of more than molecules. At this point, the molecules form an orderly aggregation, showing its unique structure and function. Supramolecular catalysts can form structures with specific functions through non‐covalent interactions (e. g., hydrogen bonding, π‐π stacking, etc.) to mimic the catalytic mechanism of natural enzymes and achieve susceptible and specific detection of biomolecules. The application of supramolecules is mainly focused on the self‐assembly of components for the construction of sensing platform. Therefore, supramolecular catalysts have a huge potential in biomolecule detection. This article focuses on the application of cyclodextrins(CD), cucurbit[n]uril(CB), porphyrins(PP) and Calix[n]arenes(CA) in the field of catalysis and in improving detection sensitivity. Research progress of supramolecular catalysts in polymerization amplification is summarized in this paper. [ABSTRACT FROM AUTHOR]

This Editorial introduces the Virtual Issue 'Chemical language of plant–microbe–microbe associations' that includes the following papers: Basak et al. (2024), Böttner et al. (2023), Brisson et al. (2023), Feng et al. (2023), Gfeller et al. (2024), Gómez‐Pérez et al. (2023), Hong et al. (2022, 2023), Hu et al. (2024), Jiang et al. (2024), Lee et al. (2024), Nakano (2024), Ökmen et al. (2023), Revillini et al. (2023), Rovenich & Thomma (2023), Simonin et al. (2022), Snelders et al. (2023), Walsh et al. (2024), Wen et al. (2023), Xia et al. (2023), Xie et al. (2023), Zhang et al. (2023, 2024), Zheng et al. (2023), Zhou et al. (2023, 2024). Access the Virtual Issue at www.newphytologist.com/virtualissues. [ABSTRACT FROM AUTHOR]

The objective of this research is to seek some new exact solutions to the (3+1)-dimensional shallow water wave equation (SWWE). By means of the Cole–Hopf transformation, the Hirota bilinear expression of the considered equation is developed. Then, taking advantage of the Hirota bilinear approach, the multi-kink solitons solutions are developed. Based on this, the resonant soliton molecules are derived via imposing certain resonant conditions (RCs). Furthermore, the new homoclinic technique is applied to explore the multi-lump solutions. To reveal the performances of the extracted solutions, the corresponding profiles are unveiled graphically through the Maple. For all we know, the derived solutions in this paper have not been probed in other literature and can expand the exact solutions of the considered equation. [ABSTRACT FROM AUTHOR]

In recent years, compounds from the Schiff base group have been intensively studied for their biological activities. Accordingly, a series of Schiff bases were synthesized from substituted aromatic aldehydes (5-chlorosalicylaldehyde) and differently substituted aromatic amines and their antimicrobial activities were evaluated. The molecular identity of compounds was confirmed using various spectroscopic techniques, such as IR and NMR spectroscopy and elemental analysis, and the molecular structure of compound 3k was determined by single-crystal X-ray analysis. The antimicrobial activity of 3a–3k compounds was examined in sixteen microorganisms (five species of bacteria and eleven species of fungi) using the microdilution method. Regarding antibacterial activity, a remarkable MIC value (0.0098 mg mL−1) and, therefore, the best activity was displayed against Proteus mirabilis for 3e, which is even stronger than the most frequently used antibiotic medications. 3f showed the best antifungal activity against Microsporum gypseum, which is stronger than standard antimycotic fluconazole, and is also an important result considering that Microsporum gypseum can cause dermatophytosis in both humans and animals. [ABSTRACT FROM AUTHOR]

A case of organic–inorganic hybridized phosphotungstate modified using aromatic organophosphonic acid, K4Na4H11[KCo2(H2O)10P4W24O92{(PhPO)2}]·48H2O (1), was successfully synthesized in conventional aqueous solution. The prominent structural feature is that the total structure of [KP4W24O92{(PhPO)2}]23− resembles a V-shaped structure, which was stabilized by two [Co(H2O)5]2+ ions. Furthermore, it can be connected into a three-dimensional mesh structure using K+ ions. Surprisingly, 1 possesses a remarkably high proton conductivity of 1.59 × 10−2 S cm−1 at 95% RH and 318 K probably due to the fact that its structure contains large amounts of lattice water molecules, coordination water molecules and counter cations. [ABSTRACT FROM AUTHOR]

The electronic and nonlinear optical (NLO) properties of Al13–X and 2Al13–X (where X represents dianhydrides BPDA, BTDA, ODPA, and 6FDA) were systematically investigated using (time-dependent) density functional theory methods. It was found that Al13 could effectively bind to dianhydride molecules via two strong Al–O bonds with high binding energies. Compared to pristine Al13 and dianhydrides, hybridized complexes Al13–X exhibit significant enhancements in both linear and nonlinear optical response properties, as evidenced by the calculated isotropic polarizability and static/dynamic first hyperpolarizabilities, respectively. The nature of the large first hyperpolarizabilities of Al13–X complexes can be understood by analyzing the low excitation energies of the key excited states and the first hyperpolarizability density. Furthermore, the dianhydride ligand is capable of bridging two aluminum clusters to form a novel D–A–D molecule, which further enhances the NLO properties of the molecules. It is hoped that the current research work will provide ideas for the rational design of such inorganic–organic hybrid complexes as novel functional electro-optical materials. [ABSTRACT FROM AUTHOR]

This work is based on the productive idea of Mulliken about the alignment of electronegativities of atoms in the process of bond formation to their geometric mean value. The paper considers in detail the case of a binary molecule and obtains formulas for the dependence of the current values of the electronegativities of the two atoms forming the molecule on time, and finds a mathematical connection between the current and initial values of electronegativities. Also, in the work the theorem on the relation between the rates of alignment of electronegativities of atoms entering into chemical bonding is formulated and proved, and a special case of this theorem is considered. [ABSTRACT FROM AUTHOR]

The core skeleton syntheses of 3′H-spiro[cyclohexane-1,1′-isobenzofuran]-2,5-dien-4-one, and their derivatives (3a–3w) of spirobisnaphthalene urnucratins, plecmillins, and lignan kadsulignan, were explored using Suzuki–Miyaura coupling product biphenols as the precursors and intramolecular oxidative dearomatization with high-valence iodine reagent PIFA as the key step in 46–91% yields. A wide range of functional groups were tolerated. Then, using this strategy in combination with the Diels–Alder reaction, two skeleton molecules (5ah and 6d) of the natural products urnucratins and plecmillins were successfully constructed in 78% and 39% overall yields, which provides a potential methodology for the total synthesis of Type D spirobisnaphthalene urnucratins and other natural products with similar structures. [ABSTRACT FROM AUTHOR]

In this paper, we take the (2+1)-dimensional generalized fifth-order KdV (fKdV) equation as an example. We obtain many wave solutions, including hybrid soliton, breather waves and solution molecules. In order to solve hybrid soliton, we give two transformation forms. For Transform one, real and complex parameters lead to different wave solutions. Soliton solutions are obtained when the parameter values are real, but some breather waves appear when the parameter values are complex. When the parameter value changes, the number of solitons and the position of the waves will also change. For Transform two, we assign the parameter values to real values and obtain the corresponding two-, three- and four-soliton solutions. The most important thing is that, on the basis of Transform one, we add different constraint conditions according to different coordinate systems, and finally get a very interesting phenomenon: soliton molecules. In addition, we give not only the three-dimensional plots but also the density plots. In general, these results will enrich the existing literature on the (2+1)-dimensional generalized fKdV equation and help to understand this kind of KdV equation. [ABSTRACT FROM AUTHOR]

In this study, we present a series of theoretically designed B2G14G14' molecules, featuring four-membered-ring heterocycles containing boron and heavy group 14 elements (G14 and G14' = Si, Ge, Sn, and Pb). Through the use of density functional theory (DFT), natural bond orbital (NBO) analysis, quantum theory of atoms in molecules (QTAIM), and electron localization function (ELF), our studies demonstrate a strong π single bond between the bridgehead G14 and G14' atoms, with minimal participation from a very weak G14-G14' σ bond. Additionally, the nucleus independent chemical shift (NICS), anisotropy of current-induced density (ACID), and adaptive natural density partitioning (AdNDP) analyses definitively establish the presence of both σ-aromaticity and π-aromaticity in these inorganic four-membered heterocyclic neutral molecules. [ABSTRACT FROM AUTHOR]

In low-energy collisions between two dipolar molecules, the long-range dipole–dipole interaction plays an important role in the scattering dynamics. Merged beam configurations offer the lowest collision energies achievable, but they generally cannot be applied to most dipole–dipole systems as the electrodes used to merge one beam would deflect the other. This paper covers the design and implementation of a merged electrostatic guide whose geometry was numerically optimized for ND3–ND3 and ND3–NH3 collisions. This device guides both beams simultaneously and makes them converge up to an effective collision angle of 2°, yielding the optimal compromise between spatial overlap and the lowest possible collision energy. We present preliminary data for inelastic ND3–ND3 collisions. [ABSTRACT FROM AUTHOR]

Electrochemotherapy (ECT) is a treatment modality that combines the electroporation of cell membranes with chemotherapy to facilitate the transport of non‐permeant molecules into cells. Several canine and feline studies have shown promising results, suggesting that ECT can be a valid adjuvant or alternative treatment option for some tumours. The objective of this paper is to provide a bibliographic review of the principles and applications of ECT in veterinary medicine and to compare to its use in human medicine. [ABSTRACT FROM AUTHOR]

This paper studies the dynamical behavior of Manakov model which is modeled by two-component nonlinear Schrödinger equation (NLSE). This system models the propagation of soliton flow using group velocity dispersion (GVD) and self-steeping coefficients. By the assistance of two recently developed integration tools, namely, generalized exponential rational function method (GERFM) and new extended direct algebraic method (NEDAM), the different kinds of solutions in the forms of bright, dark, combo and complex solitons are extracted. These types of solutions are quite well-known as optical soliton molecules or pulses in the literature. Moreover, the hyperbolic, exponential and trigonometric function solutions are recovered. In addition, stability analysis of the system is also discussed. A comparison is made between our results and those that are well-known, and the study concludes that the solutions we've reached are novel. The significance of the results is illustrated by selecting appropriate parameter values for numerical simulation and physical explanations. For the nonlinear dynamical behavior of a given system, this paper's results can improve it and demonstrate that the applied methodology is suitable. A wide range of experts in the field of engineering models will benefit from this research, according to our opinion. [ABSTRACT FROM AUTHOR]

Pressure-driven membrane-based technologies, such as microfiltration (MF), ultrafiltration (UF), and nanofiltration (NF), have been successfully implemented in recovering different types of biomolecules and high-value-added compounds from various streams. Especially, UF membranes meet the requirements for separating specific bioproducts in downstream processes, e.g. monoclonal antibodies (mAbs), which are recognized as proteins produced mainly by plasma cells. According to the importance and functionality of the mAbs, their recovery is a current challenge with these bioseparations. Nevertheless, mAbs recovery using UF-assisted processes has been smartly performed over the last decade. To the best of our knowledge, there are no reviews of the reported developments using UF technology toward mAbs separation. Therefore, the goal of this paper is to collect and elucidate ongoing research studies implemented for the featured separation of mAbs and other biotechnological protein-type molecules (e.g. adenovirus serotype, extracellular vesicles, red fluorescent protein, cyanovirin-N, among others) via ultrafiltration-aided systems. The literature evidence (e.g. research papers, patents, etc.) has been analyzed and discussed according to the purpose of the study. Importantly, the relevant findings and novel approaches are discussed in detail. To finalize this document, the advantages, drawbacks, and guidelines in applying membrane-based techniques for such a recovery are presented. [ABSTRACT FROM AUTHOR]

This paper introduces a theory to interpret future experiments to simultaneously observe angular distribution of spin-resolved Auger and photoelectrons from a molecule belonging to one of the 32 point groups. The Auger electrons are emitted in the decay of the vacancy created by photoionization. We show that the desired correlation can be completely characterized by 12 parameters which are coefficients of trigonometric functions of the spherical angles of spin quantization directions of two outgoing electrons. The expressions for the parameters themselves, although reduced to the simplest possible forms by using the symmetry properties of the molecular point group to maximum advantage, depend upon bipolar harmonics involving the propagation directions of the Auger and photoelectrons. The angular and spin correlation function thus obtained is completely general and can be readily specialized to any experimental geometry used to observe the ejected electrons. In particular, it is found that for a linear experimental arrangement with spins oriented longitudinally to the respective propagation vectors of the two electrons moving out in opposite directions, the parameters become geometry independent with their number reducing to three, which are now coefficients of the first three Legendre polynomials. Correlation between the spin-quantization directions of Auger and photoelectrons is, on the other hand, described by six parameters which do not depend upon the experimental arrangement. Directional correlation between the two outgoing electrons has also been studied without observing their spins. These angular and/or spin correlation functions are shown to take particularly simpler forms for Auger and photoelectrons emitted from linear molecules. We have applied the procedures developed in this paper to study directional correlation between photoelectrons from 2a1 orbital in a Td molecule and the Auger electrons emitted in the decay of the consequent vacancy. [ABSTRACT FROM AUTHOR]

In an earlier paper [A. D. Becke, J. Chem. Phys. 96, 2155 (1992)], Kohn–Sham density-functional calculations of the total atomization energies of the 55 molecules of the Gaussian-1 database of Pople and co-workers [J. Chem. Phys. 90, 5622 (1989); 93, 2537 (1990)] were reported. We found that the local-spin-density exchange-correlation approximation with a ‘‘gradient correction’’ for exchange gave an average deviation from experiment of only 3.7 kcal/mol. In the present work we assess the role of gradient corrections for dynamical correlation, and we enlarge our earlier survey to include 42 atomic and molecular ionization potentials and 8 proton affinities as well. We conclude that gradient corrections for correlation do not improve atomization energies, but are vitally important in electron nonconserving processes such as ionization. [ABSTRACT FROM AUTHOR]

Recent state-resolved experiments have shown that rotational energy transfer in collisions of vibrationally excited spherical top molecules is remarkably selective with respect to the fine structure components of the rovibrational states. In a recent paper [J. Chem. Phys. 93, 8731 (1990)], these results were rationalized on the basis of symmetry arguments and the Harter–Patterson theory of spectral clustering. The present paper provides numerical evidence for those assertions. Matrix elements of an atom–spherical top interaction potential are calculated using numerically accurate wave functions from spectroscopic Hamiltonians and using the approximate wave functions given by the Harter–Patterson theory. Agreement between the two calculations is satisfactory and both confirm the propensity rules derived previously, suggesting that the proposed mechanism does in fact operate in these systems. [ABSTRACT FROM AUTHOR]

In this paper we report theoretical studies of angle-resolved photoelectron spectroscopy (ARPES) and of circular dichroism in photoelectron angular distribution (CDAD) for ionization in molecules oriented in a single |JKJMJ> rotational eigenstate. These processes have been investigated also as two of the possible alternatives to photodissociation to determine orientational distribution function of rotationally state selected, oriented molecules. Expressions are derived which can be used to calculate ARPES and CDAD for such molecular species from ab initio methods or to analyze these experimentally observed spectra for extracting information about the degree of orientation of the molecular framework. These formulas are put in their simplest possible forms using the transformation properties of the molecular point group to their full advantage. The ionization amplitude is thus shown to decompose into a sum of transitions each involving the final state wave function belonging to an irreducible representation of the point group of the target molecule. It is found that, similar to the case of photodissociation, one can determine the rotational quantum number J purely from experimental photoionization data.Expressions developed herein are used to study ARPES and CDAD for ionization in a1 orbital of those rotationally state selected and oriented spherical top molecules which transform according to the Td point symmetry group. In this case, the detection-integrated cross section, singly differential in molecular orientation, is found to be independent of the photoionization dynamics and directly gives the molecular orientational function. The other ARPES and CDAD formulas are shown to depend upon the dynamics through the integrated partial cross section σ, the angularly asymmetry parameter β, the phase shift of the continuum waves representing the photoelectron, and the phase of the dipole transition amplitudes. The formulation presented in this paper sets a... [ABSTRACT FROM AUTHOR]

Abstract: A novel reversible multi-colored (red, violet, blue and yellow) film was realized using a typical photochromic dye (the color former) and docosylphosphonic acid (the color developer). A mixture of the color former/color developer exhibiting reversible multi-coloring reactions was controlled by heat-treatment of the solid phase. The structure and crystalline state of the film mixtures were investigated by UV–vis spectroscopy, X-ray diffraction and high-resolution electron diffraction measurements. The color of the films was controlled by the structural type of the photomerocyanine-form (protonated zwitterionic, zwitterionic and quinoid). The mechanism of the multi-coloring reaction was concluded to be the chemical combination of color formers and color developers, which produces red and violet colors, and when the coloration-temperature acts to separate the color formers from the color developers, yellow color appears. Furthermore, the color of the film changed from yellow to blue upon 360nm light irradiation. [Copyright &y& Elsevier]

SUMMARY: Certain transglucanases can covalently graft cellulose and mixed‐linkage β‐glucan (MLG) as donor substrates onto xyloglucan as acceptor substrate and thus exhibit cellulose:xyloglucan endotransglucosylase (CXE) and MLG:xyloglucan endotransglucosylase (MXE) activities in vivo and in vitro. However, missing information on factors that stimulate or inhibit these hetero‐transglucosylation reactions limits our insight into their biological functions. To explore factors that influence hetero‐transglucosylation, we studied Equisetum fluviatile hetero‐trans‐β‐glucanase (EfHTG), which exhibits both CXE and MXE activity, exceeding its xyloglucan:xyloglucan homo‐transglucosylation (XET) activity. Enzyme assays employed radiolabelled and fluorescently labelled oligomeric acceptor substrates, and were conducted in vitro and in cell walls (in situ). With whole denatured Equisetum cell walls as donor substrate, exogenous EfHTG (extracted from Equisetum or produced in Pichia) exhibited all three activities (CXE, MXE, XET) in competition with each other. Acting on pure cellulose as donor substrate, the CXE action of Pichia‐produced EfHTG was up to approximately 300% increased by addition of methanol‐boiled Equisetum extracts; there was no similar effect when the same enzyme acted on soluble donors (MLG or xyloglucan). The methanol‐stable factor is proposed to be expansin‐like, a suggestion supported by observations of pH dependence. Screening numerous low‐molecular‐weight compounds for hetero‐transglucanase inhibition showed that cellobiose was highly effective, inhibiting the abundant endogenous CXE and MXE (but not XET) action in Equisetum internodes. Furthermore, cellobiose retarded Equisetum stem elongation, potentially owing to its effect on hetero‐transglucosylation reactions. This work provides insight and tools to further study the role of cellulose hetero‐transglucosylation in planta by identifying factors that govern this reaction. Significance Statement: The enzyme HTG can graft segments of cellulose molecules onto xyloglucan (a hemicellulose), thereby re‐structuring the cell wall via hetero‐transglycosylation. In native walls, two endogenous hemicelluloses competed with cellulose (and with each other) as substrate. HTG more readily selected cellulose as substrate if an expansin‐enriched preparation was added. Hetero‐transglycosylation was inhibited by cellobiose – a potential tool for exploring HTG's biological functions. Interestingly, cellobiose retarded Equisetum stem elongation, suggesting a role for HTG in growth. [ABSTRACT FROM AUTHOR]

The multi‐step retrosynthesis problem can be solved by a search algorithm, such as Monte Carlo tree search (MCTS). The performance of multistep retrosynthesis, as measured by a trade‐off in search time and route solvability, therefore depends on the hyperparameters of the search algorithm. In this paper, we demonstrated the effect of three MCTS hyperparameters (number of iterations, tree depth, and tree width) on metrics such as Linear integrated speed‐accuracy score (LISAS) and Inverse efficiency score which consider both route solvability and search time. This exploration was conducted by employing three data‐driven approaches, namely a systematic grid search, Bayesian optimization over an ensemble of molecules to obtain static MCTS hyperparameters, and a machine learning approach to dynamically predict optimal MCTS hyperparameters given an input target molecule. With the obtained results on the internal dataset, we demonstrated that it is possible to identify a hyperparameter set which outperforms the current AiZynthFinder default setting. It appeared optimal across a variety of target input molecules, both on proprietary and public datasets. The settings identified with the in‐house dataset reached a solvability of 93 % and median search time of 151 s for the in‐house dataset, and a 74 % solvability and 114 s for the ChEMBL dataset. These numbers can be compared to the current default settings which solved 85 % and 73 % during a median time of 110s and 84 s, for in‐house and ChEMBL, respectively. [ABSTRACT FROM AUTHOR]

Using the example of C59Fe, the paper describes a scheme for calculating the motion of a magneto-susceptible molecular object in an alternating magnetic field. Two modes of angular displacements of the molecular structure under consideration are determined by calculation. The possibility of forming the spin of the molecule is shown. [ABSTRACT FROM AUTHOR]

Understanding charge injection at a metal/cross-linking epoxy resin (EP) interface facilitates the design and application of high-power electric and electronic devices. This paper focuses on the charge injection barrier at the metal/EP interfaces using first-principles calculation. Two fragmentary structures, obtained from cross-linking EP with amine and anhydride curing agent, were selected to construct interface models on a Cu(111) slab. The injection barrier, dipole moment, charge transfer, and vacuum energy level shift (Δ) at the interfaces were examined. The model with the anhydride groups produced higher electron and hole injection barriers than the interface model with the amine groups. The model with the amine groups had a higher Δ, which was derived from molecule dipole and charge transfer. An increase in the work function and Δ caused by an electric field caused an increase in the electron injection barrier and a decrease in the hole injection barrier. Experimental results of the methyl tetrahydrophthalic anhydride cross-linking EP showed a higher charge injection than that of m-phenylenediamine cross-linking EP, providing experimental verification of the theoretical calculation. [ABSTRACT FROM AUTHOR]

The movement of water molecules at the atomic scale within the calcium silicate hydrate (C–S–H) gel pores serves a dual role: it creates an environment for harmful chemical reactions within the pores and functions as a carrier for the transport of detrimental ions, thereby affects the mechanical properties and durability of cementitious materials. However, direct experimental observation poses substantial challenges. This study offers new insights into how temperature (253 K, 273 K, 293 K, and 313 K) affects the capillary transport of water molecules in epoxy-modified C–S–H. The findings demonstrate that the pore size undergoes continuous changes during immersion due to epoxy clustering or detachment, resulting in three scenarios: narrowing of epoxy/C–S–H channels (253 K, 273 K), channel blockage (293 K), and complete detachment (313 K). Moreover, the interactions between water molecules and epoxy lead to epoxy detachment or cluster formation on the C–S–H surface. As the temperature increases, the interaction between C–S–H and cross-linked epoxy resin weakens. The coordination between C–S–H and epoxy resin decreases, while the coordination with water increases. This paper provides valuable insights into the transport behavior of liquids within the epoxy-modified C–S–H pores of cement-based materials. It contributes to a better understanding of how liquids move and interact within the modified pore structure, which is beneficial for enhancing the performance and properties of cement-based materials. [ABSTRACT FROM AUTHOR]

Thanks to supramolecular interactions of macrocyclic compounds with their guest ions or molecules, macrocycles have found wide applications in molecular and chiral recognition, separation, transportation, molecular machines, and so on. Photoswitchable macrocycles are especially appealing and attracting more and more interest because the embedded molecular photoswitch enables dynamic control of molecular shape, conformation, and different properties by light, a non‐invasive, remote and highly tunable stimulus. With available photochromic compounds, various photoswitchable macrocycles have been developed. In this review paper, we describe the recently reported photoswitchable macrocyclic compounds, with a focus on the control of the macrocyclic structure, dynamic, photo or thermal isomerization, as well as their applications on encapsulation and release of ionic or aromatic species, on the reversible modulation of chemical, biological, electronic, fluorescent and chiroptical properties by light. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of tricyclic and tetracyclic benzothiadiazines and their derivatives, which are known for their versatility as bioactive agents. The starting materials were N-cycloamino-4-substituted-2-nitrobenzenesulfonamides 8-16, which were prepared through the condensation of 4-substituted-2-nitrobenzenesulfonyl chlorides 1--3 and cyclic amines 4--7. The intermediates, N-cycloamino-4-substituted-2-sulfanilamides 17--25, were obtained through catalytic hydrogenation of N-cycloamino-4-substituted-2-nitrobenzenesulfonamides 8--16 using a 10% palladium-on-charcoal catalyst. The potentially bioactive tricyclic and angular tetracyclic 1,2,4-benzothiadizine dioxides 26--34 were then synthesized via metal-free intramolecular N-iodosuccinimide (NIS)-mediated radical oxidative sp³ -C-H activation aminative cyclization of N-cycloamino-4-substituted-2-sulfanilamides 17--25. The yields were good to excellent (68--93%). Docking studies were conducted for N-cycloamino-4-substituted-2-nitrobenzenesulfonamides 8--16, N-cycloamino-4-substituted-2-sulfanilamides 17--25, and tricyclic and angular tetracyclic 1,2,4-benzothiadizine dioxides 26--34 for colon cancer using five protein molecules. The results showed that most of the prepared ligands exhibited higher activity than the reference drugs capecitabine, capecitabine, and fluorouracil. Among the compounds synthesized, KS7, a benzothiadiazine, showed the best activity against 6KRO. [ABSTRACT FROM AUTHOR]

In this paper, we aim to evaluate the efficacy of antidiabetic cardioprotective molecules such as Sodium-Glucose Cotransporter-2 Inhibitors (SGLT-2i) and Glucagon-like Peptide 1 Receptor Agonists (GLP-1 RAs) when used with other glucose-lowering drugs, lipid-lowering, and blood pressure (BP)-lowering drugs in a real-life setting. A retrospective, observational study on 477 patients admitted consecutively in 2019 to the outpatient clinic of a tertiary care unit for Diabetes Mellitus was conducted. Body mass index (BMI), blood pressure (BP) (both systolic and diastolic), and metabolic parameters, as well as A1c hemoglobin, fasting glycaemia and lipid profile, including total cholesterol (C), HDL-C, LDL-C and triglycerides), were evaluated at baseline and two follow-up visits were scheduled (6 months and 12 months) in order to assess the antidiabetic medication efficacy. Both SGLT-2i and GLP-1 RAs were efficient in terms of weight control reflected by BMI; metabolic control suggested by fasting glycaemia and A1c; and the diastolic component of BP control when comparing the data from the 6 and 12-month visits to the baseline, and when comparing the 12-month visit to the 6-month visit. Moreover, when comparing SGLT-2i and GLP-1 RAs with metformin, there are efficacy data for SGLT-2i at baseline in terms of BMI, fasting glycaemia, and HbA1c. In this retrospective study, both classes of cardioprotective molecules, when used in conjunction with other glucose-lowering, antihypertensive, and lipid-lowering medications, appeared to be efficient in a real-life setting for the management of T2DM. [ABSTRACT FROM AUTHOR]