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Moisture is an important factor affecting the insulation properties of transformers. Due to the limitations of macroscopic experimental methods, the diffusion of water at oil-paper interface cannot be accurately measured. Therefore, molecular dynamics method was used in this work to establish oil-paper layer model of 105 atoms. Through jointly analysing the aggregation degree, diffusion coefficient, free volume as well as radial distribution function of water molecules, the diffusion mechanism of water molecules at oil-paper interface was studied. The results show that when the initial water content in paper was high, water molecules would accumulate at oil-paper interface to form the local high-water region during heating. The polarisation of the electric field strengthened the hydrogen bonding interaction between water molecules and increased the probability of occurrence of the high-water region. Meanwhile, electric field reduced the free volume and diffusion coefficient of water molecules and rendered its diffusion coefficient anisotropic. What’s more, when the electric field was combined with the temperature field, the electric field played a leading role in the diffusion of water molecules while the temperature field was less affected. Diffusion coefficients of water molecules at different temperatures from molecular dynamics simulations were well consistent with experimental results, which verified the rationality of the model. [ABSTRACT FROM AUTHOR]

Laser desorption/ionization mass spectrometry (LDI-MS) techniques have emerged as powerful tools for analyzing compounds of natural and synthetic origins. However, conventional methods like matrix-assisted laser desorption/ionization (MALDI) often suffer from background signals and limited detection capabilities, particularly for low molecular weight compounds. Surface-assisted laser desorption/ionization (SALDI) methodologies, utilizing nanomaterials, have shown promise in overcoming these limitations. Gold nanoparticles (AuNPs) are among the most widely utilized nanomaterials in SALDI-MS applications. AuNPs offer several advantages over traditional MALDI matrices, such as reduced interference, internal calibration potential, and enhanced stability. They have been successfully employed for analyzing a diverse range of analytes, from low molecular weight (LMW) compounds to peptides, proteins, and biological entities. This paper provides a comprehensive overview of various synthesis methods, morphological properties, and comparisons with conventional MALDI matrices. Furthermore, it explores the application of AuNPs for analyzing LMW compounds and imaging various surfaces using LDI-MS techniques. [ABSTRACT FROM AUTHOR]

The carbon trimer, $ \hbox {C}_3 $ C 3 also known as propadienediylidene, is a quasi-linear molecule with an unusual electronic structure and a very flat bending potential in its ground electronic state. $ \hbox {C}_3 $ C 3 is an important species in astrophysics and carbon plasmas. Observed transition wavenumbers within and between the $ \tilde {X}\,^1\Sigma ^+_{\rm g} $ X ~ 1 Σ g + and $ \tilde {A}\,^1\Pi _{\rm u} $ A ~ 1 Π u states of $ \hbox {C}_3 $ C 3 are extracted from 21 papers and then subjected to a Measured Active Rotational-Vibrational Energy Levels (MARVEL) analysis: a corrected list of 4940 transitions are inverted to yield 1887 empirical energy levels. Uncertainties for these levels are determined using a newly implemented bootstrap method. These levels will provide input for developing a full spectroscopic model for $ \hbox {C}_3 $ C 3 which can used to generate a line list for the $ \tilde {X}\,^1\Sigma ^+_{\rm g} $ X ~ 1 Σ g + and $ \tilde {A}\,^1\Pi _{\rm u} $ A ~ 1 Π u states. [ABSTRACT FROM AUTHOR]

Oil-immersed power transformers generate characteristic gases after failure,Therefore, it is necessary to analyse and monitor the soluble gases in transformer oil samples. In this study, the DFT calculation method was used to study the adsorption properties of H2, CO, C2H2, and C2H4 gases in oil on both intrinsic MoTe2 and Rh-doped MoTe2 films. In order to analyse the adsorption characteristics, this paper first obtains the most stable Rh-doped MoTe2 monolayer model through the modelling and computational analysis of different doping sites, then, the adsorption of these gases on the material surface is studied by analysing adsorption energy, charge transfer, total state density, parting density, energy band structure, differential charge density map, molecular front orbital and desorption time, and finally concludes that Rh-MoTe2 monolayer film is the ideal material for hydrogen sensing elements, due to the extremely long desorption time of CO gas, indicating that CO gas is hard to desorption on the surface of adsorbent,which shows that this process has played a certain role in promoting CO removal. Highlights Study focused on gas adsorption using DFT: Rh-MoTe2 ideal for hydrogen sensing and effective for CO removal, intrinsic MoTe2 ineffective and required metal doping. Rh doping enhanced conductivity and gas adsorption capacity in MoTe2. Rh-MoTe2 was suitable for detecting H2, C2H2, and C2H4 gases. Desorption times vary with temperature, with CO removal particularly effective at higher temperatures. Findings suggest potential applications for Rh-MoTe2 in gas sensing and removal. [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]

Topological co-indices are topological files that think about the non-touching arrangements of vertices. Here, we think about the going with some notable topological co-indices. The mathematical qualities of atomic designs, called topological co-indices, which are utilized for the quantitative depiction of the structure of different networks are inspected. The strategy for topological co-indices is broken down as one of the methodologies for deciding the connection between the shape of a substance compounds and their properties. Theory of Chemical Graphs is a branch of graph theory that provides a wealth of possibilities for the scientist. Mathematical chemistry combines graph theory with science, relying on molecular graphs, which include vertices that represent molecules atoms and edges that represent molecules bonds. By using chart fundamental examination and allowance, we study the recently referenced topological co-indices of some engineered nuclear diagrams that as regularly as conceivable appear in clinical, manufactured, and material planning. In this paper, we examine the two sort of David Networks and gain the computation formulae of the co-indices of these organizations. Plus, we examine the results by MATLAB and gain the relationship of the co-indices which they depict the physcio-substance properties. [ABSTRACT FROM AUTHOR]

The carbon trimer, $ \hbox {C}_3 $ C 3 also known as propadienediylidene, is a quasi-linear molecule with an unusual electronic structure and a very flat bending potential in its ground electronic state. $ \hbox {C}_3 $ C 3 is an important species in astrophysics and carbon plasmas. Observed transition wavenumbers within and between the $ \tilde {X}\,^1\Sigma ^+_{\rm g} $ X ~ 1 Σ g + and $ \tilde {A}\,^1\Pi _{\rm u} $ A ~ 1 Π u states of $ \hbox {C}_3 $ C 3 are extracted from 21 papers and then subjected to a Measured Active Rotational-Vibrational Energy Levels (MARVEL) analysis: a corrected list of 4940 transitions are inverted to yield 1887 empirical energy levels. Uncertainties for these levels are determined using a newly implemented bootstrap method. These levels will provide input for developing a full spectroscopic model for $ \hbox {C}_3 $ C 3 which can used to generate a line list for the $ \tilde {X}\,^1\Sigma ^+_{\rm g} $ X ~ 1 Σ g + and $ \tilde {A}\,^1\Pi _{\rm u} $ A ~ 1 Π u states. [ABSTRACT FROM AUTHOR]

It is our pleasure to introduce a special issue of Analytical Letters comprising selected papers presented at the 13th edition of International Conference on Processes in Isotopes and Molecules (PIM 2021) held between 22 and 24 September 2021 and organized by the National Institute for Research and Development of Isotopic and Molecular Technologies in Cluj-Napoca, Romania. The Conference brought together scientists from academia, research institutes, and industry to discuss their latest results. The scientific program was completed by exhibitors presenting latest equipment and services in the field of molecular and isotopic sciences. The PIM 2021 conference promotes the exchange of ideas, experience and knowledge between scientists and engineers, as well as to encourage collaborative interdisciplinary research activities. PIM 2021 provided a stimulating communication and discussion platform in a wide range of topics from fundamentals in physics and chemistry, to applied research on energy efficiency, environment, materials and isotopic technologies. [ABSTRACT FROM AUTHOR]

The study of topological indices prompted mathematicians to venture into mathematical chemistry, specifically chemical graph theory. They are quantitative measures that reflect the topology of the molecular graph of a compound, without taking into account of any information about the chemical bonds or the atom positions. Graphene is a monolayer carbon allotrope that is tightly bound in a hexagonal honeycomb lattice. It is an eco-friendly compound and a sustainable solution for almost countless applications. In this paper, we estimate three neighborhood number-based topological indices; Mostar index, PI index and Szeged index of Graphene structure, considering all possible cases in the number of rows and hexagons. The results are obtained and corresponding graphs are plotted along with the contour plot. [ABSTRACT FROM AUTHOR]

Breast cancer is one of the most leading deadly diseases in the world whose ranks first among all oncological diseases in women and it is the second spearheading reason of cancer deadness after lung cancer in the United States. Researchers from all over the world are working for finding better ways for preventing, identifying, and treating breast cancer. Topological indices are the functions generating a numerical value from the molecular graph of compounds and they are also a useful tool to estimate the pyhsicochemical and biological properties of molecules in the quantitative structure-property (activity) relationship (QSPR/QSAR) studies. In this paper, some drugs are studied which are used for the treatment of breast cancer. CoM-polynomials based on degree are occurred for chemical graphs of these drugs and the values of some variable topological coindices are calculated via these polynomials. The results obtained by regression analysis show that the correlations of the chosen coindices with the physicochemical properties of the determined drugs are good even strong for some of them. The QSPR models are constructed using the curvilinear regression method with topological coindices. [ABSTRACT FROM AUTHOR]

The efficiency of nitrate uptake is a key point to decrease the waste of fertilizer and protect the environment. There are some signal substances participating in the nitrate control system. This paper reviewed the signals, including positive feed-forward and negative feedback signals, controlling nitrate uptake by roots. Firstly, sugar signals are related to photosynthesis and constitute a positive feed-forward signal. Sucrose had been identified as the positive feed-forward signal, and its nature was elucidated. Secondly, reduced N signals are related more generally to growth and constitute negative feedback. It is difficult to pinpoint an amino acid controlling nitrate uptake since they can convert each other. Thirdly, the interaction of two kinds of signal was analyzed. Finally, the current studies of a regulatory network of the signal molecules that control nitrate uptake and nitrate transporters in rice were reviewed. It was beneficial to understand N metabolism control. [ABSTRACT FROM AUTHOR]

During the long-term operation of a vanadium redox flow battery (VRB), the battery is subject to capacity fading as vanadium ions diffuse at different rates. Water molecules will migrate from one side to another resulting in an imbalance of electrolyte volume. An accurate model is needed to describe the capacity fading process. In existing models, a capacity fading factor due to vanadium ions crossover is well addressed, but the fading factor due to water molecule migration is often ignored. In this paper, a capacity fading model considering the migration of water molecule migration of VRB based on conservation of mass and charge is proposed. Based on this model, the electrolyte volume variation and capacity fading can be observed. Meanwhile, the mechanism of battery capacity fading can be analyzed from the imbalance of reactant concentrations. From the comparative simulation results, the influence of the migration of water molecules on capacity fading is explored. Simulation results show that the proposed model and in-depth analysis provide a cost-effective way to describe the mechanism of VRB capacity fading. [ABSTRACT FROM AUTHOR]

Several chemical and medical experimentation reveals a dependence of physicochemical and biological properties of a compound on its molecular structure. Molecular/topological descriptors/indices retrieve this dependence by employing mathematical/statistical tools to generate quantitative structure property/activity relationship (QSAR/QSPR) models. QSAR/QSPR models are regression models which theoretically relate a physicochemical/biological property to a molecular descriptor. By converting a compound to a chemical graph, graph-theoretic topological indices use algorithmic graph theory to generate QSAR/QSPR models. Degree-related molecular indices have been well-known for correlating better with certain physicochemical characteristics of compounds. In this paper, we conduct a comparative analysis to put forward the best degree-based index for correlating with physicochemical characteristics of polycyclic aromatic hydrocarbons. Two different computational techniques have been put forward and then used to conduct our comparative analysis. Our comparative testing generates several favorable and unexpected conclusions as the well-known indices such as the augmented Zagreb index, the atom-bond connectivity index, the geometric arithmetic index deliver relatively poor performance. Moreover, exceptional performance of the generalized variants of Randić and sum-connectivity indices is somehow unexpected as they significantly outperform the well-studied and well-researched degree-based indices. This warrants to study further the general Randić and sum-connectivity indices for QSAR/QSPR models. Applications to certain families of carbon polyhex aromatic nanotubes are reported. [ABSTRACT FROM AUTHOR]

Fruits and vegetables (F&V) are an indispensable part of a healthy diet. The volatile and nonvolatile compounds present in F&V constitute unique flavor substances. This paper reviews the main flavor substances present in F&V, as well as the biosynthetic pathways and molecular regulation mechanisms of these compounds. A series of compounds introduced include aromatic substances, soluble sugars and organic acids, which constitute the key flavor substances of F&V. Esters, phenols, alcohols, amino acids and terpenes are the main volatile aromatic substances, and nonvolatile substances are represented by amino acids, fatty acids and carbohydrates; The combination of these ingredients is the cause of the sour, sweet, bitter, astringent and spicy taste of these foods. This provides a theoretical basis for the study of the interaction between volatile and nonvolatile substances in F&V, and also provides a research direction for the healthy development of food in the future. [ABSTRACT FROM AUTHOR]

In this paper, odd-even effects in liquid crystals are briefly summarised. Based on the position and type of the repeating units, odd-even effects can be caused by methylene (CH2)k units either when terminating the LC molecules or separating monomers in dimers or polymers, or by the parity of the number of rigid mesogenic units separated by odd numbered methylene spacers. These odd-even effects are manifested themselves in the transition temperatures (mainly of the clearing point) and transition entropies, but they can also lead to alteration of phases, such as antiferroelectric or ferroelectric, or the appearance of tilted or orthogonal mesophases. These alternating phase and entropy properties then also lead to alternating secondary properties, such as in birefringence and elastic properties. In each category, we also discuss the theoretical considerations that can explain the observed odd-even effects. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated partial and total integral ionisation cross-sections of CF3Cl and CF2Cl2 molecules by a modified Jain-Khare semi-empirical approach during the direct and dissociative ionisation by electron impact. Present results show good agreement with the available data. Besides integral ionisation cross-sections, for the first time, we evaluated partial and total single differential cross sections for these molecules. No other results are available for single differential cross sections to compare the present calculated results. [ABSTRACT FROM AUTHOR]

In a molecular graph, molecules are associated with some numerical values these values are known as topological indices. From the M-polynomial of molecular structure we can derived degree based topological indices. We can derived chemical and physical properties of chemical compound from the topological indices. To find the strain energy, melting point, boiling point, distortion and stability of chemical compound usually mathematician used topological indices. Moreover topological indices also make relation between biological activities of compound with physical properties. In this paper, we determined the M-polynomials of the structure of the molecules of polyphenylene nanotube and nanotori. Then we derived some closed formulas for well-known topological indices, first Zagreb index, second Zagreb index, second Modified Zagreb index m M 2 (G) , general Randić index, Symmetric division index, Harmonic index, inverse sum index for polyphenylene nanotube structure of molecules. [ABSTRACT FROM AUTHOR]

In a molecular graph, molecules are associated with some numerical values these values are known as topological indices. From the M-polynomial of molecular structure we can derive degree base topological indices. We can derived chemical and physical properties of chemical compound from the topological indices. To find the strain energy, melting point, boiling point, distortion and stability of chemical compound usually mathematician used topological indices. Moreover topological indices also make relation between biological activities of compound with physical properties. In this paper, we determined the M-polynomials of the structure of the molecules of polyphenylene. Then we derived some closed formulas for well-known topological indices, first Zagreb index M 1 (G) , second Zagreb index M 2 (G) , second modified Zagreb index m M 2 (G) , general Randic index R α (G) , Symmetric division index SDD(G), Harmonic index H(G), Inverse Sum index I(G) for polyphenylene structure of molecules. [ABSTRACT FROM AUTHOR]

In the present paper we study the thermodynamic properties of superionic conductor SrCl2 at high temperatures by means of molecular dynamics method. Firstly, we calculate the melting line. Then we compute the equations of state and the response functions (heat capacity, thermal expansion coefficient, etc.) at the temperatures up to the melting. We show that the response functions show maxima or minima. Moreover, the temperature of transition into the superionic state only moderately depends on the pressure. [ABSTRACT FROM AUTHOR]

In this paper, the formalism describing the spontaneous emission rate of an excited molecule (or atom) with definite transition electric dipole moment, in vicinity of a perfect conductive wall is developed. Separately, for molecules (or atoms) with the electric dipole moment parallel and perpendicular to the wall, the spontaneous emission rate of the molecule is calculated in two ways: (1) by using the explicit form of the vector potential operator in the Fermi' golden rule and taking the expectation value in vacuum state and (2) by considering the relation between the spontaneous emission rate and the vector potential Green function, and calculating the required Green function components of the space at the presence of a perfect conductive wall. The two methods yield the same expression for the spontaneous emission rate. The agreement of the results with some previous works is shown and the variations of the spontaneous emission rate for each dipole moment orientation are demonstrated. [ABSTRACT FROM AUTHOR]

TCAD-based numerical investigation of RingFET has been presented in this paper for the detection of gas molecules. Sensitivity of the device has been assessed by calculating the change in off-state current with the change in gate work-function (which changes due to the presence of gas molecule). The behavior of the device has also been compared with the equivalent bulk MOSFET and it was observed that RingFET architecture shows 23% higher sensitivity against gas molecules than equivalent bulk MOSFET. Also, the degradation in device sensitivity with applied drain bias is higher in bulk MOSFET. Optimization in the sensitivity parameter has been done by using different channel materials like GaN, InGaN, and GaAs. Compared to GaAs and silicon, GaN-based RingFET is more sensitive towards gas molecules in the sub-threshold region (due to the wider band gap) besides having lower drain current than GaAs and silicon-based RingFET. [ABSTRACT FROM AUTHOR]

Iron-based catalysts can be used as de-NOx catalysts due to their good adsorption performance to gas molecules. However, the adsorption behaviours of NH3, NO, and O2 molecules on ferrous oxide surface are unclear. In this paper, the adsorption properties of NH3, NO, and O2 molecules over FeO (100) surface and oxygen-defected FeO (100) surface were studied by a density functional theory calculation. The Fe-top of the FeO (100) surface is the most active site. NH3 and NO can be adsorbed on the Fe-top sites by N terminal. The adsorption of O2 on the Hollow site of the FeO (100) surface has a larger adsorption energy. When oxygen-defected presents on the FeO (100) surface, the adsorption performances of NH3 and NO on the Fe-top sites are slightly decreased. NO and O2 can be adsorbed on the O-defected site, in which the adsorption energy of O2 is larger. For the adsorption of double molecules, O2 + NH3 or O2 + NO adsorbed on the FeO (100) surface have synergistic effects, respectively, which enhance the adsorption performance. Moreover, the co-adsorption behaviours of O2 + NH3 and O2 + NO on the O-defected FeO (100) surface also occur. [ABSTRACT FROM AUTHOR]

SupposeGis a molecular graph and Γ is a subgroup of its symmetry group. The Graovac–Pisanski index (GP index in short) of G with respect to Γ is a symmetry-based topological index. This topological index gives a distance-symmetry description of the molecular graphG. The aim of this paper is to compute the GP index of some classes of fullerenes and fullerene-like molecules. [ABSTRACT FROM AUTHOR]

Molecules containing sulfur play an important role in atmospheric chemistry, but their reactivity in such environment is far from being well characterised. Therefore, important transient species might still have to be disclosed. In this regard, this paper aims at contributing to this field by means of the computational spectroscopic characterisation of potentially relevant atmospheric species, such as the CH 2 O 2 S isomers. Based on our computational investigation, the most stable species are the carbonothionic O,S- and O,O-acids. In addition to them, the sulfene molecule has also been considered. For all these species, the equilibrium structure and the corresponding rotational constants have been accurately evaluated using a coupled-cluster-based composite approach. All the other parameters required for the simulation of the rotational and ro-vibrational spectra have been obtained by exploiting density functional theory. [ABSTRACT FROM AUTHOR]

In this paper an explanation of the dependence of photoluminescence of detonation nanodiamonds in water on the type of functional surface groups due to the manifestation of inductive and mesomeric electronic effects on the interface "nanodiamond - surface groups – water molecules" is proposed. This explanation based on the experimental results of the study of photoluminescence of detonation nanodiamonds with different surface functionalization and theoretical calculations of the electron density on the surface of nanoparticles. The hypothesis can be extended to other functionalizations of nanodiamonds, which will allow to control the stability and photoluminescent properties of colloidal systems "nanodiamonds-solvent" through the functionalization of the surface of nanoparticles. [ABSTRACT FROM AUTHOR]

Neural network algorithms are gradually applied to the field of chemical informatics. In this paper, the neural network models are used to predict the properties of compounds based on Molecular Information. We predict the aqueous solubility of compounds, and evaluate the prediction results of the Neural Networks including CNN, RNN, DNN, SNN. The performance of the models in predicting the solubility is able to meet or exceed the predicted effect of the method based on the molecular structure (ESOL). DNN model performance is of more accuracy, and RNN performance is of better stability. This method can directly avoid complex molecular structure characterisation, and provide a convenient and flexible way to predict properties of compounds. [ABSTRACT FROM AUTHOR]

In this study, N, N-dibenzylaniline, an essential intermediate with broad significance in organic syntheses organic synthesis, was synthesized and characterized based on its spectrum. The single-crystal structure of the compound was confirmed using X-ray. The crystal structure of the compound, as calculated and optimized by DFT, was consistent with the crystal structure obtained by X-ray single-crystal diffraction. The functional groups of the compound were analyzed using vibrational analysis. Molecular docking analysis revealed the potential pharmacological effects of the compound. The molecular electrostatic potential and frontier molecular orbitals of the compound were studied, and its physical and chemical properties were revealed. [ABSTRACT FROM AUTHOR]

In this study, density functional theory (DFT) calculations were initially conducted to explore the molecular structure, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), LUMO-HOMO energies, as well as the excited states of new piperazine derivatives using the CAM-B3LYP/Def2TZV level of theory. Detailed quantum molecular descriptors for the compounds, including ionization potential (IP), electron affinities (EA), hardness (η), softness (S), electronegativity (μ), electrophilic index (ω), electron-donating power (ω−), electron accepting power (ω+), and energy gap (Eg), were calculated. The chemical properties and bioactivity of these compounds, such as molecular weight, lipophilicity, number of hydrogen bond (HB) donors and acceptors, molar refractivity, polarity, solubility, flexibility and saturation, were also investigated. Subsequently, a molecular docking study was performed to identify effective compounds that could act as strong inhibitors against Parkinson's Disease. The Michaelis-Menten constant (Km) was determined using the CAM-B3LYP/Def2TZV level of theory. The binding energy between the protein with ID:5CGJ and the organic compounds demonstrated excellent binding affinity. Therefore, the structures: 4-(4-methylpiperazin-1-yl)-4-oxo-N-(4-sulfamoylphenyl)butanamide (21), N-(4-((4-methylpiperazin-1-yl)methyl)phenyl)-4-(morpholinomethyl) benzamide (22), cаn bе usеd for potential application аgаinst Parkinson's Disease. [ABSTRACT FROM AUTHOR]

The present study aims to quantify the electron-induced inelastic and elastic processes for molecules of industrial relevance, furfural and p-benzoquinone. We have computed inelastic cross-sections (Qinel), elastic cross-sections (Qel) and total cross-sections (QT) through spherical complex optical potential (SCOP) formalism, from ionisation energy (IE) to 5000 eV. The continuum and discrete contributions of the Qinel have been calculated in terms of ionisation (Qion) and excitation (∑Qexc) cross-sections, respectively, by employing the complex scattering potential-ionisation contribution (CSP-iC) method. A novel 2-parameter semi-empirical method (2p-SEM), a useful approach applicable for the large molecules 55 < Z < 95 for calculating QT, has been proposed and validated. Computed results are compared with previous experimental and theoretical data. We have also estimated the dielectric constant (ε) using various methods and correlations with molecular ionisation for these applied molecules. [ABSTRACT FROM AUTHOR]

Our focus is upon a noncovalent molecular complex after its formation. In earlier work, we determined the 'impenetrable' volumes of the molecules A and B in a series of bimolecular complexes. In this paper, we investigate the amount and distribution of electronic charge that is excluded from these impenetrable volumes in each complex. We show that the strength of the interaction correlates reasonably well with the amount of this excluded charge. In accordance with the Hellmann–Feynman theorem and Feynman's analysis of 'dispersion' forces, the noncovalent bond between A and B can be understood as the Coulombic interaction between the impenetrable volumes and the excluded electronic charge. [ABSTRACT FROM AUTHOR]

An infinite number of solitons, as well as soliton molecules belonging different families, are allowed to propagate stably along a given dispersion-managed optical fibre. In this paper, we propose a semi-analytical method to systematically find a finite number of solitons and two-soliton molecules. Determined solitons and soliton molecules present a greatest power gap between them, to make them sufficiently distinct symbols for encoding several bits of information per symbol in a multilevel modulation format in fibre-optic transmission systems. Furthermore, for illustrative purposes, we discuss the possibility of encoding three bits per symbol. [ABSTRACT FROM AUTHOR]

The polyethylene glycols are currently considered an essential class of polymers with several applications in industry, medicine, and biology. The aqueous two-phase (ATP) extraction based on polyethylene glycol (PEG) and certain salts have gained the attention for further usage in protein purification as a simple and cheap technique; however, it is still under development. In this paper, the formation of ATP systems by PEG as a model polymer and sodium sulfate was studied focusing on (1) some of the conditions under which the polymer may have definite compensatory solute properties, and (2) the analysis of the crystallization degree and the conditions for forming di and triphasic systems. The results demonstrate that the polymer in some systems may have inherent compensatory solute-like behavior which becomes evident under certain conditions, including the type of the other solute molecules, solvent type, concentration, and pH of the system. [ABSTRACT FROM AUTHOR]

The small molecule compounds like pesticide, veterinary drug, bio-toxin, and heavy metal are widely found in animals, plants, soil, etc. Excessive compounds residues will have a bad influence on human health and the environment. Thus, it is extremely urgent that can detect the small molecules simultaneously. At present, many researches of simultaneous detection for small molecules using the method of an immunoassays have been reported thanks to its advantages of fast speed, simple operation, and high specificity. The small molecules have only one antigenic determinant, so the competitive immunoassay is the main method for small molecule compounds detection. In this paper, our main job is to describe the development of immunoassay for multi-residue detection of small molecule compounds and introduce three ways to complete the analysis of multi-residue immunoassay of small molecule compounds. We also summarize deficiencies and make an expectation of the immunoassays. [ABSTRACT FROM AUTHOR]

Staphylococcus epidermidis, a harmless human skin colonizer, is a significant nosocomial pathogen in predisposed hosts because of its capability to form a biofilm on indwelling medical devices. In a recent paper, the purification and identification of the pentadecanal produced by the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125, able to impair S. epidermidis biofilm formation, were reported. Here the authors report on the chemical synthesis of pentadecanal derivatives, their anti-biofilm activity on S. epidermidis, and their action in combination with antibiotics. The results clearly indicate that the pentadecanal derivatives were able to prevent, to a different extent, biofilm formation and that pentadecanoic acid positively modulated the antimicrobial activity of the vancomycin. The cytotoxicity of these new anti-biofilm molecules was tested on two different immortalized eukaryotic cell lines in view of their potential applications. [ABSTRACT FROM AUTHOR]

The study aimed at phytochemical profiling and evaluating the bioactive potentials of aqueous bark extracts of a mangrove plant Avicennia officinalis by in vitro and in silico techniques. The quantitative phytochemical study exhibited total phenol and total flavonoid content as 16.6 mg GAE/g and 82 mg QE/g respectively. The GC-MS study indicated presence of five major compounds viz. 2,6-dimethoxy phenol; 4-[(1E)-3-hydroxy-1-propenyl)- 2-methoxy phenol; 2,5-dimethoxybenzyl acetate; vitamin-E; stigmasterol. The in silico molecular docking of compounds 2,6-dimethoxy phenol; 2,5-dimethoxy benzene methanol acetate and stigmasterol indicated strong binding interactions, validating the antiradical, antidiabetic, anti-inflammatory and antibacterial activities. The extract exhibited DPPH, ABTS, α-glucosidase and protein denaturation inhibition activities with IC50 values of 112.78, 76.34, 257.4, 99.86 μg/mL respectively suggesting the antioxidant, antidiabetic and anti-inflammatory potential of the plant. The antiglycation study exhibited inhibition of fructosamine and congo red with 50.63% and 64.39% at 200 μg/mL concentration. The biofilm inhibitory concentration required to reduce biofilm coverage by 50% values for the extract was 625 μg/mL. The results provide a basis for new pharmacological avenues and further research of this plant. [ABSTRACT FROM AUTHOR]

Two spirooxazine (SO) compounds containing bromobutyl substituents on 1-position (SO1) and 9′- position (SO2) have been synthesized and characterized by 1H-NMR, IR and ESI-MS in this paper. SO1-g-PMMA and SO2-g-PMMA polymer were prepared by grafting SO1 and SO2 onto PMMA through C-Br bonding sites. Also, SOs were doped into PMMA matrix to afford SO1-d-PMMA and SO2-d-PMMA. Photochromic behaviors of these compounds have been studied. Compared with SO1, SO2 exhibited better photoresponse and slower bleaching in dichloromethane solution. Inserted into polymer films, the decoloration process of SOs were significantly retarded and it was found that the fading curves fitted a first-order equation; As regard to four polymers, 1-position grafting (SO2-g-PMMA) can cause a higher reduction degree on the thermal fading rate. [ABSTRACT FROM PUBLISHER]

The family Pentatomidae is one of the largest families of the sub-order Heteroptera, comprising 4722 species belonging to 896 genera. In the present paper, we analysed a partial ∼600 bp COI sequence of 14 species of family Pentatomidae, collected from northern part of India. For seven species viz., Tolumnia antennata Distant, 1902, Cahara jugatoria (Lethierry, 1891), Bagrada hilaris (Burmeister, 1835), Plautia viridicollis (Westwood, 1837), Priassus exemptus (Walker, 1868), Dalpada neoclavata (Rider, 1998) and Dalpada affinis (Dallas, 1851), this is the first ever molecular study which has generated distinct barcodes for each. The COI sequences of these seven species have been added to the existing database at GenBank NCBI which can be used for their identification. The database analysis shows mean K2P divergence of 2.5% at intraspecific level, 11.9% at interspecific level and 16.37% at intergeneric level, thereby indicating a hierarchical increase in K2P mean divergence across different taxonomic levels. [ABSTRACT FROM AUTHOR]

It is shown by tiling that only three out of the thirteen title molecules are planar. Using our recent concept of quasi-molecule ('tile') or its generalisation, all participating tiles have been here optimised in a few spin-states both at the DFT level with the B3LYP and M06-2X functionals, and using the CCSD(T) method. While borazine ( $ 1,4,6-{\rm B}_3{\rm N}_3{\rm H}_6 $ 1 , 4 , 6 − B 3 N 3 H 6 ) was synthesised in the forties of the past century, its next up-lying planar isomer ( $ 1,3,4-{\rm B}_3{\rm N}_3{\rm H}_6 $ 1 , 3 , 4 − B 3 N 3 H 6 or $ {\rm BHNHNHBHBHNH} $ BHNHNHBHBHNH ) was not. Quasi-tetratomic tiles are then shown to be shape-determining while 5-body terms and beyond are shape-preserving. The need to bring the notion of planarity as a probabilistic outcome is also examined, and the concept of planarity likelihood ratio (index) introduced. As for the above borazine isomers, this index is also predicted to be unit for $ 1,4-{\rm B}_4{\rm N}_2{\rm H}_6 $ 1 , 4 − B 4 N 2 H 6 , a result that is corroborated upon its optimisation at DFT/B3LYP/AVTZ level but not with M06-2X by which it is predicted as quasi-planar. Nevertheless, recent work with a derivative of diazatetraborinine where all atoms are bonded to substituent atoms or groups of atoms confirms the planarity of the $ {\rm B}_4{\rm N}_2 $ B 4 N 2 ring. Such a result is further corroborated at the gold-standard CCSD(T) level. Although planarity is also predicted for $ {\rm B}_6{\rm H}_6 $ B 6 H 6 , DFT and CCSD(T) frequency calculations suggest it to be likely a saddle point. [ABSTRACT FROM AUTHOR]

Liquid chalcogen-halogen A2X2(A: S, Se, X: Cl, Br) is a racemic mixture of enantiomers between left-handed (L) and right-handed (D) chiral molecules. The lone-pair orbital of the chalcogen atom significantly affects the molecular conformation and intermolecular interaction. The latter depends on the size of the orbital and number density. High-energy X-ray diffraction measurements and reverse Monte Carlo (RMC) structural modelling were performed for liquid S2Cl2in addition to the previous structural analysis for liquid Se2Br2. By comparing the structures of the RMC model and hard-sphere Monte Carlo (HSMC) model, the effect of refinement on the experimental structure factor can be analysed. In this paper, nearest-neighbour intermolecular pairs are classified in terms of enantiomer pairs such as like-pair (L-L and D-D) and unlike-pair (L-D). As a result, the effect of a strong intermolecular attractive interaction is detected in Se2Br2as increasing the number of like-pairs with geometrical advantages from HSMC to RMC, whereas that of an intermolecular repulsive interaction is observed in S2Cl2as elongation of the averaged intermolecular S-S distance from HSMC to RMC. These results are consistent with the results of theab initiomolecular dynamics simulation for Se2Cl2and S2Cl2. [ABSTRACT FROM PUBLISHER]

We describe our observation of strongly oriented total electronic angular momentumJin O(3P2), Ne(3P2), and He(3S1) atoms emerging from a bent magnetic multipole guide, as measured by resonant multiphoton ionisation. This was contrary to our expectation because no additional (uniform) magnetic fields were applied to orient the atoms behind the exit of the guide. Two- and three-photon ionisation techniques were employed to determine the degree ofJpolarisation, from which we infer that atoms become oriented as a result of a combination of weak fringe fields, possible stray fields, and the fact that molecular beam packets do not oscillate around the geometric center of the bent multipole guide. We conclude that similar effects may exist in other, related experiments and that a detailed characterisation of the degree of orientation is required prior to any study of chemical dynamics or spectroscopy. This paper should serve as a warning for anybody using similar devices not to assume isotropic angular momentum distributions of atoms and molecules emerging from a magnetic guide or a decelerator, particularly when it is bent; whenever possible, the possibility for aJanisotropy should be experimentally checked. [ABSTRACT FROM PUBLISHER]

Cucurbit[n]urils (CB[n]) are a new family of macrocyclic synthetic host molecules that are cyclic oligomers composed of a varying number of glycoluril units bridged by methylene groups. The most important feature of CB[n]s is their ability to form inclusion complexes (host-guest complexes) with a very wide range of solid, liquid, and gaseous compounds by molecular complexation. During the past few years, a considerable number of research papers have been focused on the use of CB[n]s to enhance or quench the fluorescence intensity of different guest molecules and to develop CB[n]-induced or quench spectrofluorimetric methods. In this review, the various spectrofluorimetric methods based on a host-inclusion complex of CB[n] with a various analytes in solution are presented and discussed. [ABSTRACT FROM AUTHOR]

Contingentism, generally contrasted with law necessitarianism, is the view that the laws of nature are contingent. It is often coupled with the claim that their contingency is knowable a priori. This paper considers Bird's [2001, 2002, 2005, 2007] arguments for the thesis that, necessarily, salt dissolves in water; and it defends his view against Beebee's [2001] and Psillos's [2002] contingentist objections. A new contingentist objection is offered and several reasons for scepticism about its success are raised. It is concluded that certain higher-level laws describing the behaviours of molecular compounds may be necessary due to their dependence on underlying physical laws, and that the modal status of laws of nature cannot be determined a priori, as the structural features of the substances and properties they govern must first be investigated. [ABSTRACT FROM AUTHOR]

A thymol-based molecule was synthesized and characterized. The anti-proliferative activity of molecule 4 was tested in vitro in three cancer cell lines and a healthy human cell line. The results showed that this molecule had cytotoxic effects on the human cell lines studied. Images of the cells were taken using the Leica inverted microscope. Molecular docking, molecular dynamics simulation, density functional theory calculations, and computational pharmacokinetics analysis of molecule 4 were carried out. The binding mode of the molecule with ABL1 was revealed through molecular docking. The stability of the complexes procured from the docking was assessed through molecular dynamics simulation. The computational analysis revealed that the antiproliferative effect of molecule 4 on the cancer cell lines might result from its potential to inhibit ABL1. In addition, molecule 4 was found to have ideal pharmacokinetic properties to be used as a drug candidate molecule. Hence, the experimental and computational studies indicated its derivatives might have promising antiproliferative activity. [ABSTRACT FROM AUTHOR]

The aim of this work is to determine the influence of the terminal polar group of nematic compounds, namely -OCF3, -NCS, -CN, -F, on the induction of the SmA phase in their mixtures with compounds having terminal non-polar groups. The former group of compounds has positive dielectric anisotropy, and the latter negative. The phase transition temperatures of binary mixtures were measured using polarising thermomicroscopy, and phase diagrams for investigated systems were constructed. The strength of the SmA phase induction increases upon the increase of the polarity of compounds. The strongest induction is observed in systems with compounds having a terminal trifluoromethoxy group. Although compounds with the cyano group have the highest polarity, their ability for the SmA phase induction is smaller due to their dimerisation. [ABSTRACT FROM AUTHOR]

A new series of liquid crystals consisting of biphenyl unit connected to phenyl core system have been successfully prepared wherein various substituents X= OCH3, F, Cl, Br and I were introduced in the para position of the imine fragment while the length of terminal alkoxy chain of seven carbon atoms was intact. The mesomorphic and thermal studies by POM and DSC exhibit dominant enantiotropic nematic (N) phase. A relatively weak magnetism was detected with vibrating sample magnetometer (VSM) for compounds 3F and 3I at room temperature, wherein the magnetic strength of fluoro-substituted compound appeared stronger than the iodo-substituted compound. The connectivity between the substituents X and their kinetic stability associated with the changes in HOMO-LUMO energy gap value (ΔEgap) supports that the terminal substituents X have great influence on the ΔEgap which can be ascribed to the chemical activity of the compounds. Present study shows an increase in the ΔEgap from OCH3 < I < Br < Cl < F, where the largest ΔEgap indicates high molecular kinetic stability and low chemical reactivity because adding electrons to high-lying LUMO is energetically unfavourable, resulting in disruption of the molecular packing and reduction of nematogenic, which were validated by DSC and POM. [ABSTRACT FROM AUTHOR]

The diffusion of molecules on interstellar grain surfaces is one of the most important driving forces for the molecular complexity in the interstellar medium. Due to the lack of laboratory measurements, astrochemical modeling of grain surface processes usually assumes a constant ratio between the diffusion energy barrier and the desorption energy. This over-simplification inevitably causes large uncertainty in model predictions. We present a new measurement of the diffusion of CO $ _2 $ 2 molecules on the surface of non-porous amorphous solid water (np-ASW), an analog of the ice mantle that covers cosmic dust grains. A small coverage of CO $ _2 $ 2 was deposited onto an np-ASW surface at 40 K, the subsequent warming of the ice activated the diffusion of CO $ _2 $ 2 molecules, and a transition from isolated CO $ _2 $ 2 to CO $ _2 $ 2 clusters was seen in the infrared spectra. To obtain the diffusion energy barrier and pre-exponential factor simultaneously, a set of isothermal experiments were carried out. The values for the diffusion energy barrier and pre-exponential factor were found to be $ 1300\pm 110 $ 1300 ± 110 K and $ 10^{7.6\pm 0.8} $ 10 7.6 ± 0.8 s $ ^{-1} $ − 1 . A comparison with prior laboratory measurements on diffusion is discussed. [ABSTRACT FROM AUTHOR]

Previously, I investigated phase transitions in an assembly of biaxial molecules interacting via dispersion forces. Consequently, a uniaxial and two biaxial nematic phases, as well as a disco-nematic phase, were reported to appear in such an assembly of biaxial molecules. However, the investigation was performed at limited points in the space of anisotropy parameters ɛx and ɛy. In the present study, phase transitions at all points in the space of anisotropy parameters are investigated because understanding phase transitions in a system of flexible molecules, whose shape and/or anisotropy of molecular interaction change with temperature or density, is valuable and important. [ABSTRACT FROM AUTHOR]

Cyclophosphamide (CP) is one of the most extensively used antineoplastic drug, but the nephrotoxicity caused by this drug is a major limiting factor for its use. Nerolidol (NERO) is a natural bioactive compound with diverse pharmacological actions. In Vitro and in vivo study was performed using HK-2 renal cells and Swiss Albino mice. Cell lines and animals were treated with NERO 25 and 50 µM + 30 µM CP (in vitro), 200 and 400 mg/kg, p.o. NERO from day 1 to day 15 + 200 mg/kg, i.p. CP on day 17 as single intraperitoneal injection (in vivo). The makers of oxidative stress, renal-specific injury markers, inflammation, apoptosis, fibrosis, and histopathological changes were studied. The study's outcome showed a significant reduction in the level of malonaldehyde and interleukin-6 (p < 0.01), tumor necrosis factor-α, IL-1β (p < 0.001), and an increase in the superoxide dismutase, catalase, glutathione and interleukin-10 level (p < 0.01), in the in vivo study when treated with NERO 400 and compared with CP 200. In Vitro study showed reduced expression of nuclear factor kappa light chain enhancer of activated B cells, cleaved caspase-3, kidney injury molecule-1 and transforming growth factor-β-1 (p < 0.001), when treated with NERO 50 µM whereas NERO 25 µM only reduced the level of cleaved caspase-3 (p < 0.05) when compared with 30 µM. NERO 400 also reduced uric acid (p < 0.05), urea (p < 0.01), blood urea nitrogen, and serum creatinine levels (p < 0.001) and increased the level of blood-urea-nitrogen/creatinine ratio (p < 0.001). Additionally, the level of fibrosis-specific markers such as transforming growth factor-β1, hyaluronic acid (p < 0.01), 4-hydroxyproline, a collagen-rich area in Masson's' trichome stain, and Smad3 expression was also significantly reduced (p < 0.001). Furthermore, the outcome of multiple renal staining showed structural reversal aberrations, reduction of the thick basement membrane, and glycogen level toward normal when treated with NERO 400. Thus, the study showed a novel mechanistic modality of NERO against cyclophosphamide-induced renal toxicity. The outcome of this study can be considered a step closer to the development of an adjuvant to mitigate cyclophosphamide-induced renal toxicity among patients treated with cyclophosphamide. [ABSTRACT FROM AUTHOR]

Cancer is the second leading cause of death in the world and one of the major public health problems. Curcumin has anticancer activity including inducing apoptosis and inhibiting proliferation and invasion of tumours by suppressing a variety of cellular signalling pathways. It also possesses anti-tumour activity on different human cancers such as breast cancer, lung cancer, head and neck squamous cell carcinoma, prostate cancer, and brain tumours. In vitro and in vivo trails, curcumin inhibits tumour development and metastasis by inhibiting many pathways that regulate signalling in malignant cells, including Ras, p53, extracellular signal-regulated kinases (ERK), Wnt-protein kinase B (Akt), MAPKs, and PI3K. Curcumin can also inhibit IKK, EGFR, -catenin, cyclin D1, tumour necrosis factor (TNF), and anti-apoptotic genes such as Bcl-X and Bcl-2 along with downregulating nuclear transcription factors like NF-κB, which reduces the formation of pro-inflammatory cytokines like chemokines, TNF-, Interleukins and IL-1, IL-2, IL-6, IL-8, IL-12. [ABSTRACT FROM AUTHOR]