Triplet Interaction Research Articles

Volumetric, viscometric and spectroscopic studies of molecular interactions of glutamic acid with potassium sorbate and sodium benzoate in aqueous medium at T = 293.15–313.15 K

The empirically procured data of physical properties like density and viscosity for the solutions of glutamic acid (Glu) with various concentrations in H2O and H2O + (1.5, 2.0 and 2.5 mol.kg-1) potassium sorbate (PS)/sodium benzoate (SB) at five different temperature (T = 293.15–313.15 K) and atmospheric pressure (101.1 kPa) has been used in order to calculate volumetric and viscometric parameters such as apparent molar volume (Vϕ), partial apparent molar volume (V∅0), limiting apparent molar expansibility (E∅0), viscosity B-coefficients (BJ), pair and triplet interaction co-efficients etc. Structure making properties of glu being present with PS/SB in the solutions are explained by the positive Hepler’s constant (∂2V∅0/∂T2)P values. This structure building tendency of Glu is further supported by the positive (BJ) and negative (∂BJ/∂T) values. For both solute and solvent Gibbs free energy of activation (Δμ10,#andΔμ20,# respectively) has been evaluated and including these parameters the thermodynamic parameters like ΔS0,#andΔH0,# profound the stability of the transition state. For a refined understanding of distinct intermolecular interactions prevailing in the designed systems the co-sphere overlap model has been employed. The procured results acknowledge that solute-solvent interactions reduce with a rise in temperature. Additionally, FTIR spectral analysis was carried out on the studied systems and relying on the shifting oh O-H stretching band the presence of hydrogen bond as well as different kinds of interactions are confirmed for the investigated system.

Volumetric and Acoustic Studies of Interactions between L-Phenylalanine and 1-Hexyl-3-Methylimidazolium Bromide in Aqueous Solution

Experimental density (ρ) and ultrasonic velocity (c) for phenylglycine in ( 0.01, 0.03, 0.05 and 0.05) mol.kg−1 aqueous solutions of 1-hexyl-3-methylimidazolium bromide at T = (313.15 and 318.15) K. Collected values for density and ultrasonic velocity were used to compute the apparent molar volumes (V f ), the apparent molar volumes at infinite dilution (), partial molar isentropic compression (K f ,s ) and partial molar isentropic compression at infinite dilution (). Also recorded data of these mixtures were utilized to calculate pair and triplet interaction coefficients. Such thermodynamic characteristics can be used to investigate the solvation behaviour, structure formation, and many sorts of interactions in (phenylglycine + water + 1-hexyl-3-methylimidazolium bromide) ternary solutions.

Study of the interactions of monosaccharides D(+)-glucose and D(−)-fructose in aqueous diammonium hydrogen phosphate over the temperature range T=(288.15–318.15) K

The interactions of monosaccharides D(+)-glucose and D(−)-fructose in aqueous solutions of diammonium hydrogen phosphate (DAP) as a function of temperature have been investigated. The values of densities and speeds of sound have been measured for the system of monosaccharides and salt in aqueous solution. Densities and speed of sound for D(+)-glucose and D(−)-fructose in (0.5, 1.0, 1.5 and 2.0) mol⋅kg−1 aqueous solutions of diammonium hydrogen phosphate (DAP) are measured at T = (288.15, 298.15, 308.15 and 318.15) K and experimental pressure p = 0.1 MPa. The apparent molar volume,Vφ the partial molar volume, VφO and standard partial molar volumes of transfer, Δ VφO for D(+)-glucose and D(−)-fructose in aqueous solutions of diammonium hydrogen phosphate (DAP) have been calculated from density data. Apparent molar isentropic compression,Kϕ,s partial molar isentropic compression, Kϕ,so and partial molar isentropic compression of transfer, ΔKϕ,so have been calculated from speed of sound measurements. The expansibility parameter (∂Vϕ0 /∂T)p and its derivative (∂2 Vϕ0 /∂2 T)p along with pair (VAB, KAB) and triplet (VABB, KABB) interaction coefficients have also been calculated. The results have been interpreted in terms of solute − solute and solute–solvent interactions prevailing in these ternary systems.

Volumetric, acoustic and viscometric studies of solute-solute and solute-solvent interactions of glycine and its peptides in aqueous solutions of an antidepressant drug at different temperatures

From the density (ρ), speed of sound (u) and viscosity (η) measurements, the interactions of glycine, glycylglycine and glycylglycylglycine with antidepressant drug, nortriptyline hydrochloride have been investigated in aqueous medium at temperatures, T = (293.15–313.15) K and experimental pressure p = 0.1 MPa. From the experimental density measurements, apparent molar volume (VΦ), limiting apparent molar volume (VoΦ) and partial molar volumes of transfer (VoΦ,tr) have been determined for various solutions of glycine, glycylglycine and glycylglycylglycine in aqueous nortriptyline hydrochloride. In addition, using speed of sound data, apparent molar isentropic compression (Ks,Φ), limiting apparent molar isentropic compression (Kos,Φ) and partial molar isentropic compression of transfer (Kos,Φ,tr) have been calculated. Pair and triplet interaction coefficients are also determined from VoΦ,tr values using McMillan-Mayer theory. Further, apparent molar expansibility (EoΦ) and Hepler's constant values ∂EoΦ∂TP have been evaluated to assist the interpretations earned from the volumetric and acoustic analysis. The viscosity coefficients A and B, viscosity B-coefficient of transfer (Btr) and temperature derivative of B-coefficients (dB/dT) have been determined from viscosity data. The results were interpreted in terms of different kinds of intermolecular interactions present in the ternary systems (amino acid/peptides + water + nortriptyline hydrochloride) through a cosphere overlap model. The Hepler’s constant and temperature derivative of B-coefficients (dB/dT) confirms the structure breaking nature of the solute.

Interaction behavior of sucrose in aqueous tributylmethylammonium chloride solutions at various temperatures: A volumetric, ultrasonic and viscometric study

Physical properties such as density (ρ), sound speed (u) and viscosity (η) for varied compositions of a saccharide (sucrose) in water and mixed aqueous tributylmethylammonium chloride solvent media has been scrutinised at five discrete temperatures ranging (293.15 K - 313.15 K) and under ambient pressure (101.3 kPa). The empirically procured data has been employed to enumerate different volumetric, acoustic and viscometric parameters like apparent molar parameters (Kϕ,s, Vϕ), partial molar parameters (K0ϕ,s, V0ϕ), transfer parameters (K0ϕ,s,tr, V0ϕ,tr, Btr), hydration number, pair and triplet interaction coefficients, solvation number, viscosity B-coefficient etc. The temperature derivative of viscosity B-coefficient i.e. dB/dT values have been utilized to examine structure making ability of the solute. Also, Gibbs free energy of activation for both solute and solvent has been determined and the influence of temperature on the solute-solvent interactions has been addressed. Moreover, the co-sphere overlap model has been employed for better comprehension of various prevalent intermolecular interactions in the considered systems.

Analysing the molecular interactions of ternary (lactose + water + tributylmethylammonium chloride) solutions at different temperatures via physicochemical methods

The interactions of lactose with tributylmethylammonium chloride (Bu3MeNCl) as the function of temperature have been studied by amalgamation of volumetric, acoustic and viscometric methods. Density, ultrasonic speed, and viscosity for varying concentrations of lactose in water and in (0.020, 0.039, 0.059, 0.079) mol.kg−1 aqueous solutions of Bu3MeNCl have been determined at five distinct temperatures (T = 293.15–313.15) K. These experimental values have been used to calculate apparent molar volume, Vϕ, limiting apparent molar volume, V0ϕ, apparent molar isentropic compression, Kϕ,s, limiting apparent molar isentropic compression, K0ϕ,s, viscosity B-coefficient, their transfer values, pair and triplet interaction coefficients, and hydration number nH. The Gibbs free energy of activation for solvent (Δµ01#) and Gibbs free energy of activation for lactose (Δµ02#) in water and in aqueous solutions of Bu3MeNCl have also been assessed and the obtained results support the outcome of volumetric, acoustic and viscometric parameters. These parameters provide better understanding of molecular interactions like solute-solute, solute-solvent interactions present in the systems. Further, it helps in determining structural and functional properties of studied systems and acquired results revealed that the solutions are characterized predominantly by solute-solvent interactions. Also, the values of second derivative of limiting apparent molar volume with respect to temperature indicated that the lactose monohydrate behaves as a structure maker in aqueous tributylmethylammonium chloride solutions.

Thermophysical studies of protonated and deprotonated glycine in aqueous sodium acetate buffer solutions at different temperatures

Interactions of glycine in water and in (0.10, 0.50 and 1.00) aqueous sodium acetate buffer solutions of pH (1.00 and 12.40) have been investigated at different temperatures, T/K = (298.15-318.15). Densities, and viscosities, of glycine in water and in aqueous sodium acetate buffer solutions have been measured. The obtained density data have been used to calculate apparent molar volume, , limiting partial molar volume, , limiting partial molar volumes of transfer, . Viscosity B-coefficient, viscosity B-coefficient of transfer, , Activation free energies per mole of the solute, and solvent, have been calculated from viscosity data. Further, second order derivative of partial molar expansion coefficient and dependence of coefficients on temperature is useful in measuring the structure making and breaking behavior of solute in these systems. Pair and triplet interaction coefficients for both the properties were also calculated. Thus, the results obtained from volumetric and viscometric studies are of considerable importance to identify different type of interactions (i.e. H-bonding, van der Waal’s interactions)in these systems.

Molecular Interactions of Diphenhydramine-hydrochloride with Some Imidazolium-Based Ionic Liquids in Aqueous Media at T = 293.15-313.15 K: Volumetric, Acoustic, and UV Absorption Studies.

From the density (ρ) and speed-of-sound (u) measurements, the interactions of the drug diphenhydramine-hydrochloride (DPH) with three imidazolium-based ionic liquids (ILs) (1-butyl-3-methylimidazolium chloride, [C4mim][Cl], 1-hexyl-3-methylimidazolium chloride1, [C6mim][Cl], and 1-methyl-3-octylimidazolium chloride, [C8mim][Cl]) have been investigated in aqueous medium at T = 293.15–313.15 K and experimental pressure p = 0.1 MPa. From the density calculations, the apparent molar volume (Vϕ) and the apparent partial molar volumes of transfer (ΔtVϕo) have been determined for various solutions of DPH in aqueous solutions of different ILs. In addition, from the speed-of-sound data, the apparent molar isentropic compressibility (Kϕ), apparent partial molar isentropic compressibility (Kϕo), and apparent partial molar isentropic compressibility of transfer (ΔtKϕο) have been calculated. The pair and triplet interaction coefficients are derived from apparent partial molar volumes of transfer. For the present mixtures, the absorption spectra have been also recorded using a UV–visible spectrophotometer. Using Hepler’s constant, the structure-making nature of the solute has been confirmed. All these calculated parameters provide detailed insights into various physicochemical interactions prevailing in the ternary system and confirm the presence of a strong attractive interaction between DPH and ILs.

A new and alternative look at nonlinear Alfvénic states

The formulation for studying nonlinear Alfvénic states, sustainable in Hall Magnetohydrodynamics (HMHD), becomes considerably simpler and more tractable when circularly polarized Beltrami vectors (the eigenstates of linear HMHD) are used as the basis functions. Nonlinear HMHD is, then, reduced to a rather simple looking set of scalar equations from which a model problem of three interacting Beltrami modes is formulated and analytically solved. The triplet interactions span a variety of familiar nonlinear processes leading to a redistribution as well as periodic exchange of energy. The energy exchange processes (whose strength is measured by an energy exchange/depletion time) will, perhaps, play a dominant role in determining the spectral content of an eventual Alfvénic state. All nonlinearities (sensitive functions of the interacting wave vectors) operate at par, and none is dominant over any substantial region of k-space; their intricate interplay prevents a “universal” picture from emerging; few generalizations on the processes that may, for instance, lead to a turbulent state, are possible. However, the theory can definitely claim: (1) the energy tends to flow from lower to higher k and (2) the higher kz (in the direction of the ambient magnetic field) components of a mode with a given k are depleted/oscillate faster—in some cases much faster. It is noteworthy that the mode coupling is the strongest (with the shortest depletion time) when the participating wave vectors are nearly perpendicular; perhaps, an expected consequence of the curl (cross product) nonlinearities. Numerical simulations will be necessary to help create a fully reliable picture.

Effect of ethylene glycol/diethylene glycol/triethylene glycol on the thermodynamics of the aqueous biotin solutions at various temperatures

Acoustic and volumetric parameters for the liquid mixture (water + Biotin + ethylene glycol/diethylene glycol/triethylene glycol) are evaluated at different temperatures (288.15 K, 298.15 K, 308.15 K, and 318.15 K) and constant pressure of 0.1 MPa over the range of biotin concentrations (0.0000, 0.0015, 0.0025, and 0.0035) mol·Kg-1. The experimental work was carried out by Anton Paar DSA 5000 M, where the density (ρ) and the speed of sound (c) are measured, which are later used to determine the various derived thermodynamic properties, such as, apparent molar properties (apparent molar volume, Vϕ; apparent molar isentropic compression,Kϕ,S), the partial molar properties (partial molar volume, Vϕ0; partial molar isentropic compression, Kϕ,S0), the partial molar transfer properties (partial molar volume of transfer, ΔVϕ0; partial molar isentropic compression of transfer, ΔKϕ,S0) and the partial molar expansibility (Eϕ0) along with its first derivative ∂Eϕ0/∂TP. The obtained results are explained in terms of the kind of intermolecular interactions developed in the mixture using the co-sphere overlap model. Further, with the partial molar properties, the pair and triplet interaction coefficients (VAB,KAB; VABB, KABB) are calculated.

A discrete interaction numerical model for coagulation and fragmentation of marine detritic particulate matter (Coagfrag v.1)

Abstract. A simplified model, representing the dynamics of marine organic particles in a given size range experiencing coagulation and fragmentation reactions, is developed. The framework is based on a discrete size spectrum on which reactions act to exchange properties between different particle sizes. The reactions are prescribed according to triplet interactions. Coagulation combines two particle sizes to yield a third one, while fragmentation breaks a given particle size into two (i.e. the inverse of the coagulation reaction). The complete set of reactions is given by all the permutations of two particle sizes associated with a third one. Since, by design, some reactions yield particle sizes that are outside the resolved size range of the spectrum, a closure is developed to take into account this unresolved range and satisfy global constraints such as mass conservation. In order to minimize the number of tracers required to apply this model to an ocean general circulation model, focus is placed on the robustness of the model to the particle size resolution. Thus, numerical experiments were designed to study the dependence of the results on (i) the number of particle size bins used to discretize a given size range (i.e. the resolution) and (ii) the type of discretization (i.e. linear vs. nonlinear). The results demonstrate that in a linearly size-discretized configuration, the model is independent of the resolution. However, important biases are observed in a nonlinear discretization. A first attempt to mitigate the effect of nonlinearity of the size spectrum is then presented and shows significant improvement in reducing the observed biases.

Volumetric Properties of aqueous solutions of Arabinose, Xylose and Galactose in presence / absence of Sodium Cyclamate

Sugars can affect our blood glucose (sugar), weight and blood fats. Synthetic sugars (artificial sweetener) provide little or no calories or carbohydrate or do not increase blood sugar. In food and pharmaceutical industries, blends of sweeteners are commonly used to design the food products and pharmaceutical doses, the information regarding type and extent of sweetener-sweetener and sweetener -water interactions and taste quality of the solution required. The aqueous solutions of arabinose, xylose and galactose with and without cyclamate are studied. Densities of solutions of arabinose, xylose and galactose in presence of 0.05, 0.15 and 0.3 m sodium cyclamate have been measured at 298.15K. Partial molar volumes, apparent specific volumes, partial molar volumes of transfer and doublet and triplet interaction parameters have been calculated. The information obtained from these parameters has been used to understand type and extent of sweetener-sweetener and sweetener -water interactions and taste quality of the solution.

Fibonacci Turbulence

Never is the difference between thermal equilibrium and turbulence so dramatic, as when a quadratic invariant makes the equilibrium statistics exactly Gaussian with independently fluctuating modes. That happens in two very different yet deeply connected classes of systems: incompressible hydrodynamics and resonantly interacting waves. This work presents the first case of a detailed information-theoretic analysis of turbulence in such strongly interacting systems. The analysis elucidates the fundamental roles of space and time in setting the cascade direction and the changes of the statistics along it. We introduce a beautifully simple yet rich family of discrete models with neighboring triplet interactions and show that it has families of quadratic conservation laws defined by the Fibonacci numbers. Depending on the single model parameter, three types of turbulence were found: single direct cascade, double cascade, and the first ever case of a single inverse cascade. We describe quantitatively how deviation from thermal equilibrium all the way to turbulent cascades makes statistics increasingly non-Gaussian and find the self-similar form of the one-mode probability distribution. We reveal where the information (entropy deficit) is encoded and disentangle the communication channels between modes, as quantified by the mutual information in pairs and the interaction information inside triplets.

Free energy landscape of RNA binding dynamics in start codon recognition by eukaryotic ribosomal pre-initiation complex.

Specific interaction between the start codon, 5'-AUG-3', and the anticodon, 5'-CAU-3', ensures accurate initiation of translation. Recent studies show that several near-cognate start codons (e.g. GUG and CUG) can play a role in initiating translation in eukaryotes. However, the mechanism allowing initiation through mismatched base-pairs at the ribosomal decoding site is still unclear at an atomic level. In this work, we propose an extended simulation-based method to evaluate free energy profiles, through computing the distance between each base-pair of the triplet interactions involved in recognition of start codons in eukaryotic translation pre-initiation complex. Our method provides not only the free energy penalty for mismatched start codons relative to the AUG start codon, but also the preferred pathways of transitions between bound and unbound states, which has not been described by previous studies. To verify the method, the binding dynamics of cognate (AUG) and near-cognate start codons (CUG and GUG) were simulated. Evaluated free energy profiles agree with experimentally observed changes in initiation frequencies from respective codons. This work proposes for the first time how a G:U mismatch at the first position of codon (GUG)-anticodon base-pairs destabilizes the accommodation in the initiating eukaryotic ribosome and how initiation at a CUG codon is nearly as strong as, or sometimes stronger than, that at a GUG codon. Our method is expected to be applied to study the affinity changes for various mismatched base-pairs.

Heider and coevolutionary balance: From discrete to continuous phase transition.

Structural balance in social complex networks has been modeled with two types of triplet interactions. First is the interaction that only considers the dynamic role for links or relationships (Heider balance), and second is the interaction that considers both individual opinions (nodes) and relationships in network dynamics (coevolutionary balance). The question is, as the temperature varies, which is a measure of the average irrationality of individuals in a society, how structural balance can be created or destroyed by each of these triplet interactions. We use statistical mechanics methods and observe through analytical calculation and numerical simulation that unlike the Heider balance triplet interaction which has a discrete phase transition, the coevolutionary balance has a continuous phase transition. The critical temperature of the presented model changes with the root square of the network size, which is a linear dependence in the thermal Heider balance.

Singlet-triplet interaction of the adiabatic terms [formula omitted] and [formula omitted] in the linear triatomic molecules

The paper introduces the 4x4 vibronic matrix that describes singlet–triplet interaction of adiabatic terms 1Σ+ and 3Σ+ via deformation π-modes of the linear triatomic system. Our analysis takes into account spin-orbital coupling in ab initio Breit-Pauli form in the framework of two-electronic model. It is shown that the symmetry operators of electronic Hamiltonian include both space operations (acting on electronic coordinates) and matrix operations (acting on electronic spins). Eigenvalues of vibronic matrix (i.e. potential energy surfaces) are invariants of the molecular symmetry group C∞ν. The 4x4 vibronic matrix includes 4 electrostatic parameters and 3 parameters caused by spin-orbital interaction.

Volumetric and acoustic investigation of l-leucine and N-acetyl l-leucine in the aqueous solution of 1-hexyl-3-methylimidazolium bromide [HMIm] [br] at different temperatures

Present study reports density (ρ) and ultrasonic velocity (c) for l-leucine and N-acetyl l-leucine in (0.00, 0.005, 0.01, 0.03 and 0.05) mol.kg−1 aqueous solutions of 1-hexyl-3-methylimidazolium bromide [HMIm] [Br] at T = (288.15, 298.15, 308.15 and 318.15) K. Experimental data for density and ultrasonic velocity were used to calculate the apparent molar volumes (Vϕ), the apparent molar volumes at infinite dilution (Vϕ0), partial molar isentropic compression (Kϕ,s) and partial molar isentropic compression at infinite dilution (Kϕ,s0). Further pair and triplet interaction coefficients have been calculated from volumetric and acoustic studies. These Thermodynamic parameters are useful to study the solvation behaviour, structure making and different types of interactions present in the ternary solutions of (amino acids + water + [HMIm] [Br]).

MiRCoop: Identifying Cooperating miRNAs via Kernel Based Interaction Tests.

Although miRNAs can cause widespread changes in expression programs, single miRNAs typically induce mild repression on their targets. Cooperativity among miRNAs is reported as one strategy to overcome this constraint. Expanding the catalog of synergistic miRNAs is critical for understanding gene regulation and for developing miRNA-based therapeutics. In this study, we develop miRCoop to identify synergistic miRNA pairs that have weak or no repression on the target mRNA individually, but when act together, induce strong repression. miRCoop uses kernel-based statistical interaction tests, together with miRNA and mRNA target information. We apply our approach to patient data of two different cancer types. In kidney cancer, we identify 66 putative triplets. For 64 of these triplets, there is at least one common transcription factor that potentially regulates all participating RNAs of the triplet, supporting a functional association among them. Furthermore, we find that identified triplets are enriched for certain biological processes that are relevant to kidney cancer. Some of the synergistic miRNAs are very closely encoded in the genome, hinting a functional association among them. In applying the method on tumor data with the primary liver site, we find 3105 potential triplet interactions. We believe miRCoop can aid our understanding of the complex regulatory interactions in different health and disease states of the cell and can help in designing miRNA-based therapies. Matlab code for the methodology is provided in https://github.com/guldenolgun/miRCoop.

Interactional Behavior and Hydration Characteristics of Polyhydroxysolutes (d(+)-Xylose and d(−)-Ribose) in Aqueous Solutions of Dipotassium Oxalate at Different Temperatures

Thermodynamic properties revealing the hydration characteristics and structural effects of saccharides in mixed aqueous solutions generate considerable information for the growth of pharmaceutical and food industries. In this study, the apparent molar volumes, Vϕ, and the apparent molar isentropic compression, Kϕ,s, for monosaccharides (d(+)-xylose and d(−)-ribose) within the concentration range 0.1–1.0 mol·kg–1 in 0.0, 0.2, 0.4, and 0.6 mol·kg–1 aqueous solutions of dipotassium oxalate (K2C2O4) have been calculated from densities and speeds of sound measured at temperatures T = 288.15, 298.15, 308.15, and 318.15 K and experimental pressure p = 0.1 MPa. Thermodynamic parameters, partial molar volumes, Vϕo, partial molar volumes of transfer, ΔVϕo, partial molar isentropic compression, Kϕ,so, and partial molar isentropic compression of transfer, ΔKϕ,so, and hydration numbers, Nw, are also derived for the said monosaccharides. The effect of temperature on these parameters is studied, and further the expansion coefficients, (∂Vϕ0/∂T)p, (∂2Vϕ0/∂2T)p, and pair (VAB, KAB) and triplet (VABB, KABB) interaction coefficients are determined for monosaccharides. The results indicate the occurrence of strong solute–cosolute (hydrophilic–ionic and hydrophilic–hydrophilic type) interactions in these systems, which increase with the increasing concentration of saccharides and dipotassium oxalate.

Volumetric and acoustic properties of amino acids L-Leucine and L-Serine in aqueous solution of ammonium dihydrogen phosphate (ADP) at different temperatures and concentrations

The physicochemical properties of amino acids like L-Leucine and L-Serine in aqueous solution of ammonium dihydrogen Phosphate (ADP) at different temperature analysed by volumetric and acoustic methods. By using density data, apparent molar volume Vϕ, partial molar volume Vϕ0 and standard partial molar volume of transfer ΔVϕ0 have been evaluated. From speed of sound data, apparent molar isentropic compression Kϕ,s apparent partial molar isentropic compression Kϕ,s0 and partial molar isentropic compression of transfer ΔKϕ,so have been calculated. The pair and triplet interaction coefficient have also been calculated. The results have been interpreted in terms of solute–solute and solvent–solvent interactions.