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In this work, we have studied the potential and fields as well as stationary structures of ion acoustic mode in a plasma containing ions and Vasyliunas–Schamel distributed electrons through the derivation and analysis of the modified Zakharov–Kuznetsov (mZK) equation. This nonlinear evolution equation is derived by employing the reductive perturbative technique (RPT). The mZK equation executes the evolution of weakly dispersive waves under the simultaneous effect of nonlinear and dispersive forces. We have used numerical methods for obtaining the solutions. The results show the parametric influence on the evolution of field quantities in plasma waves.

In this work, we have looked into the amplitude modulation and formation of enveloping soliton in a dense plasma with thermal degeneracy pressure expressions as a strong laser beam falls on it. We have focused on the situation where an intense laser interacts with plasma and we have made use of a new topological treatment of problems containing a set of coupled differential equations. At first, we have solved the equations to arrive at the dispersion relation. We have studied phase plots using particle-in-cell (PIC) simulation from where Kelvin–Helmholtz-type instabilities were observed. We have made use of the homotopy perturbation technique to find out more about the evolution of density, electric field, velocity streamlines, and the subsequent amplitude modulation with different types of nonlinearity. We identified the range of plasma and laser parameters in which such nonlinearity is important. The results obtained here will help interpret different phenomena that arise in laser–plasma interaction and plasma astrophysics where shocks solitons, and so on in dense hot plasma can be studied in laboratory scales.

The dust-ion collisional effect is investigated for dust ion acoustic waves (DIAWs) in the spherical and cylindrical geometry. Using the reductive perturbation technique (RPT), the evolution equation is derived with an additional damping term. An approximate analytical time-dependent solitary wave solution is obtained for the evolution equation in nonplaner geometry. It is seen that dust ion collisional frequency plays an important role in the existence region of the solitary wave structure in the nonplanar geometry. It is also seen that dust-ion collisional frequency and spectral index $\kappa $ have a significant role in the amplitude and width of the solitary wave. Additionally, we have numerically investigated the parametric influence on the solitonic evolution mechanism which will help understand the process better.

DNA polymerase β (Polβ) is crucial for the base excision repair (BER) pathway of DNA damage repair and is an attractive target for suppressing tumorigenesis as well as chemotherapeutic intervention of cancer. In this study, a unique strategy of scaffold-hopping-based molecular editing of a bioactive agent NSC-666719was investigated, which led to the development of new molecular motifs with Polβ inhibitory activity. NSC compound and its analogs (two series) were prepared, focusing on pharmacophore-based molecular diversity. Most compounds showed higher activities than the parent NSC-666719and exhibited effects on apoptosis. The inhibitory activity of Polβ was evaluated in both in vitroreconstituted and in vivointact cell systems. Compound 10edemonstrated significant Polβ interaction and inhibition characteristics, including direct, non-covalent, reversible, and comparable binding affinity. The investigated approach is useful, and the discovered novel analogs have a high potential for developing as anticancer therapeutics.

A new single-stage, T-type five-level inverter, which is based on a dual quasi Z-source, and an improved HERIC structure has been proposed in this paper. It is envisaged that the proposed power converter could find applications in the area of grid-connected PV generation. The conventional topologies, which are based on two-stage conversion are bulky and expensive. The proposed single-stage system overcomes these disadvantages. Furthermore, the issue of leakage current, which is of paramount interest in PV systems is addressed by the adaptation of a PWM scheme along with the employment of passive filters. It is shown that the leakage current is effectively suppressed by the elimination of the high-frequency transitions across the parasitic capacitance due to the combined effort of the PWM scheme and the filter. The proposed power converter also displays the capability of supporting reactive power, which is one of the essential requirements for the present-day PV inverters. The steady-state and the dynamic performances of the proposed power converter are assessed with simulation studies and are then experimentally validated. A comparative study of the proposed power converter with the existing quasi-Z-source-based power converters is also undertaken, which reveals the advantages of the proposed configuration.

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In this paper we have studied the gradual evolution of stationary formations in electron acoustic waves at a finite temperature quantum plasma. We have made use of Quantum hydrodynamics model equations and obtained the KdV-Burgers equation. From here we showed how the amplitude modulated solitons evolve from double layer structures through shock fronts and ultimately converging into solitary structures. We have studied the various parametric influences on such stationary structure and also showed how the gradual variations of these parameter affect the transition from one form to another. The results thus obtained will help in the generation and structure of the structures in their respective domain. Much of the experiments on dense plasma will benefit from the parametric study. Further we have studied amplitude modulation followed by a detailed study on chaos.

In this paper, we discuss the time evolution of a forced KdV equation by using a standard reductive perturbation technique. Using conservation laws, we derive the time evolution a KdV equation with an external force. Further, we make use of our newly designed method of flux correction along with the predictor-corrector scheme to study the growth of field quantities with time over a spatial span. The results obtained by using our new technique agree perfectly with the findings from the standard reductive perturbation technique. Our method will find quick acceptance in dealing with nonlinear plasma phenomena. Once we set up the basic equations, we can feed them into our scheme, and the results will automatically follow. We can even check the dependence of different waveforms as the initial and the boundary conditions.

We present atomistic molecular dynamics results for fully hydrated bilayers composed of ceramide NS-24:0, free fatty acid 24:0 and cholesterol, to address the effect of the different components in the stratum corneum (the outermost layer of skin) lipid matrix on its structural properties. Bilayers containing ceramide molecules show higher in-plane density and hence lower rate of passive transport compared to phospholipid bilayers. At physiological temperatures, for all composition ratios explored, the lipids are in a gel phase with ordered lipid tails. However, the large asymmetry in the lengths of the two tails of the ceramide molecule leads to a fluidlike environment at the bilayer midplane. The lateral pressure profiles show large local variations across the bilayer for pure ceramide or any of the two-component mixtures. Close to the skin composition ratio, the lateral pressure fluctuations are greatly suppressed, the ceramide tails from the two leaflets interdigitate significantly, the depression in local density at the interleaflet region is lowered, and the bilayers have lowered elastic moduli. This indicates that the observed composition ratio in the stratum corneum lipid layer is responsible for both the good barrier properties and the stability of the lipid structure against mechanical stresses.

The synthesis of polyolefins with two metallocene catalysts is explored via a simple Monte Carlo simulation in the two cases of a batch and a semibatch reactor. The algorithm we develop can be applied, in principle, to an arbitrary number of catalysts with different propensities toward the formation of long chain branches. We compare our model to an experimental two-catalyst system, in which one of the catalysts makes only linear chains and the ratio of the two catalysts is varied, to synthesize a series of different molar mass resins. Results from our simulations show good agreement with experimentally measured molecular weight distributions, the ratio of unsaturated to saturated chain ends (found by 13C NMR) and the number of branches per 10000C. We also examine the effect on the amount of branching when molecular hydrogen gas is added to the system to act as a chain transfer agent.