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As a result of their natural capacity to recover harmonic current and reactive power from alternating current sources, power electronic devices utilized in conjunction with nonlinear loads have the potential to generate significant harmonic problems within the power system when employed in this way. When this occurs, voltage instability occurs, which must be avoided in order to maintain the consistency and dependability of the power system's power flow. With this approach, the series controller has been replaced by a multilevel modular controller in order to improve power handling capability and achieve higher modular levels with minimal distortions. The shunt compensator is the most effective way to achieve an extremely protected energy system as well as righteous steadiness in electric potential difference under a variety of load constraints. The DQ thesis is employed in this proposed converter to separate the harmonic components by establishing reference frame current, which is accomplished by machine learning techniques. As part of the constant mode operation, the PI controller contributes to maintaining the direct current-potential difference, which is given to the PWM generator. Optimization of the values of K p and K i is accomplished by the use of particle swarm optimization (PSO). The construction of this power system simulation model has been made feasible by the use of time-fluctuating characteristics modeling and the MATLAB programming environment. The new (unified power flow controller) UPFC research that has been made available is persuasive in its capacity to reduce distortions and watt-less power components while simultaneously enhancing efficiency and reducing costs., Competing Interests: The authors of this manuscript declare that they do not have any conflicts of interest., (Copyright © 2022 Shoaib Kamal et al.)

Short peptides composed of phenylalanine and sequences derived from amyloidogenic peptides have the ability to self-assemble to form nanostructures including hydrogels. The self-assembly of peptides composed of only hydrophobic amino acids and aliphatic protecting groups have not been investigated in detail. We have examined various aspects of nanostructures formed by N-terminal t-butyloxycarbonyl-protected aliphatic dipeptide methyl esters dissolved in various solvents. Scanning electron microscopic images indicate that depending on the sequence, position of the amino acid and solvent of dissolution, the peptides self-assemble into superstructures such as nanotubes and needles particularly from aqueous mixtures of organic solvents. Crystallization was not required for self-assembly into nanostructures. Circular dichroism and attenuated total internal reflection fourier transform infrared spectroscopy studies indicate that the peptides adopt β-conformation in the superstructures both in solution and solid state. The nanostructures composed of entirely aliphatic moieties have the ability to bind to aromatic dyes such as Rhodamine 6G, Nile red and Congo red. They also bind to Thioflavin T although the structures do not resemble amyloid fibrils. The powder X-ray diffraction patterns suggest distinctive packing of the monomers. These structures are stabilized by intermolecular hydrogen bonds and hydrophobic interactions resulting in superstructures containing long distance order and were devoid of hemolytic activity., (© 2017 Wiley Periodicals, Inc.)

Background: Amyloid fibrils, which are implicated in several diseases, are highly ordered structures formed by aggregation of proteins. Intriguingly, several short peptides, some of which are unrelated to the disease-causing proteins, also aggregate to form amyloid fibrils in vitro. The aggregation behavior of these short peptides can be modulated so that they form nanostructures that are not in any way related to amyloid fibrils. These observations have led to extensive research aimed at getting insights into how peptides aggregate to form amyloids as well as non-amyloidogenic structures., Methods: This review examines the aggregation behavior of peptides that form highly polymorphic structures including fibrils, nanotubes, nanospheres and hydrogels. The review also describes how short peptides composed of only two and three hydrophobic and aromatic amino acids can selfassemble to form nanotubes and nanospheres., Results: Peptides with widely varying amino acid composition and lengths aggregate to form indistinguishable fibrils and nanostructures. The potential application of these aggregated structures in the design of novel biomaterials is reviewed and highlighted., Conclusion: It is evident that highly polymorphic aggregated structures of peptides can be obtained by varying conditions such as solvent of dissolution, temperatures, pH and even surfaces of deposition., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)