252 research outputs found

    Complex free energy landscapes in biaxial nematics and role of repulsive interactions : A Wang - Landau study

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    General quadratic Hamiltonian models, describing interaction between crystal molecules (typically with D2hD_{2h} symmetry) take into account couplings between their uniaxial and biaxial tensors. While the attractive contributions arising from interactions between similar tensors of the participating molecules provide for eventual condensation of the respective orders at suitably low temperatures, the role of cross-coupling between unlike tensors is not fully appreciated. Our recent study with an advanced Monte Carlo technique (entropic sampling) showed clearly the increasing relevance of this cross term in determining the phase diagram, contravening in some regions of model parameter space, the predictions of mean field theory and standard Monte Carlo simulation results. In this context, we investigated the phase diagrams and the nature of the phases therein, on two trajectories in the parameter space: one is a line in the interior region of biaxial stability believed to be representative of the real systems, and the second is the extensively investigated parabolic path resulting from the London dispersion approximation. In both the cases, we find the destabilizing effect of increased cross-coupling interactions, which invariably result in the formation of local biaxial organizations inhomogeneously distributed. This manifests as a small, but unmistakable, contribution of biaxial order in the uniaxial phase.The free energy profiles computed in the present study as a function of the two dominant order parameters indicate complex landscapes, reflecting the difficulties in the ready realization of the biaxial phase in the laboratory.Comment: 23 pages, 12 figure

    TREATMENT POSSIBILITIES FOR ACQUIRED AND HEREDITARY DISEASES BY GENE THERAPY: A REVIEW

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    Therapeutic nucleic acids demand specificity and accuracy in design as well as delivery strategies used in replacement or silencing of the target gene. Gene therapy is believed to be the therapy in which the root cause of the diseases can be treated at the molecular level. Generally gene therapy helps in the identification of the origin of the disorder instead of using drugs to diminish or control the symptoms. The application of nucleic acids to treat and control diseases is known as “gene therapy.” Gene therapy consists on the substitution or addition of a functional gene into the nucleus of a living cell, in order to treat a disease or repair a dysfunction, caused by this gene failure. This therapy is used to correct defective genes, which are responsible for genetic diseases. Thus, gene therapy can be used to prevent, treat or regulate hereditary or acquired disorders, by the production of therapeutic proteins. The gene therapy is mediated by the use of viral and non-viral vectors to transport foreign genes into somatic cells to restorative defective genes. This review focuses on viral vectors in detail

    Crowd Size Estimation and Detecting Social Distancing Using Raspberry PI and Opencv

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    In this covid19 pandemic the number of people gathering at public places and festivals are restricted and maintaining social distancing is practiced throughout the world. Managing the crowd is always a challenging task. It requires some kind of monitoring technology. In this paper, we develop a device that detects and provide human count and also detects people who are not maintaining social distancing . The work depicted above was finished using a Raspberry Pi 3 board with OpenCV-Python.This method can effectively manage crowds
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