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The present focus of environmental science is centred on addressing the significant and controversial challenge of separating acid gases As a result scientists are actively engaged in developing high performance membranes that can effectively transport gases An important factor in achieving superior gas separation efficiency is the ability to control the rate of chemical component penetration through the membrane This has led to an increasing interest in mixed matrix membranes MMMs that contain inorganic nanoparticles homogeneously dispersed within the polymer matrix which are becoming a popular alternative to traditional polymeric membranes In this work the morphological properties of polyurethane PU membrane treated with titanium dioxide TiO2 which is functionalized with methylene diisocyanate MDI were studied and its gas transport properties like selectivity and permeability were evaluated FTIR XRD TG DTG and SEM analyses were performed for neat and MMMs to study their morphological properties in phase I of the research Our results showed that MDI modification improved the dispersion of TiO2 in the PU matrix resulting in a more uniform and compact membrane structure Moreover gas permeability results showed that incorporating up to 1 wt of unfunctionalized and functionalized TiO2 into the PU matrix enhanced the CO2 N2 selectivity by 71 69 and 78 42 respectively Overall this study demonstrated the potential of MDI aided tailoring of TiO2 for dispersion engineering in PU MMMs which can lead to improved gas separation performance The findings have implications for developing advanced materials for gas separation applications particularly in industrial processes such as natural gas purification and carbon capture

The present focus of environmental science is centred on addressing the significant and controversial challenge of separating acid gases As a result scientists are actively engaged in developing high performance membranes that can effectively transport gases An important factor in achieving superior gas separation efficiency is the ability to control the rate of chemical component penetration through the membrane This has led to an increasing interest in mixed matrix membranes MMMs that contain inorganic nanoparticles homogeneously dispersed within the polymer matrix which are becoming a popular alternative to traditional polymeric membranes In this work the morphological properties of polyurethane PU membrane treated with titanium dioxide TiO2 which is functionalized with methylene diisocyanate MDI were studied and its gas transport properties like selectivity and permeability were evaluated FTIR XRD TG DTG and SEM analyses were performed for neat and MMMs to study their morphological properties in phase I of the research Our results showed that MDI modification improved the dispersion of TiO2 in the PU matrix resulting in a more uniform and compact membrane structure Moreover gas permeability results showed that incorporating up to 1 wt of unfunctionalized and functionalized TiO2 into the PU matrix enhanced the CO2 N2 selectivity by 71 69 and 78 42 respectively Overall this study demonstrated the potential of MDI aided tailoring of TiO2 for dispersion engineering in PU MMMs which can lead to improved gas separation performance The findings have implications for developing advanced materials for gas separation applications particularly in industrial processes such as natural gas purification and carbon capture

We consider a Generalized Uncertainty Principle (GUP) framework which predicts a maximal uncertainty in momentum and minimal uncertainties both in position and momentum. We apply supersymmetric quantum mechanics method and the shape invariance condition to obtain the exact harmonic oscillator eigenvalues in this GUP context. We find the supersymmetric partner Hamiltonians and show that the harmonic oscillator belongs to a hierarchy of Hamiltonians with a shift in momentum representation and different masses and frequencies. We also study the effect of a uniform electric field on the harmonic oscillator energy spectrum in this setup., Comment: 14 pages, 1 figure, to appear in Physics Letters B

We consider a Generalized Uncertainty Principle (GUP) framework which predicts a maximal uncertainty in momentum and minimal uncertainties both in position and momentum. We apply supersymmetric quantum mechanics method and the shape invariance condition to obtain the exact harmonic oscillator eigenvalues in this GUP context. We find the supersymmetric partner Hamiltonians and show that the harmonic oscillator belongs to a hierarchy of Hamiltonians with a shift in momentum representation and different masses and frequencies. We also study the effect of a uniform electric field on the harmonic oscillator energy spectrum in this setup., Comment: 14 pages, 1 figure, to appear in Physics Letters B

In this paper we compute the radiative correction to the mass of the kink in $\phi^4$ theory in 1+1 dimensions, using an alternative renormalization program. In this newly proposed renormalization program the breaking of the translational invariance and the topological nature of the problem, due to the presence of the kink, is automatically taken into account. This will naturally lead to uniquely defined position dependent counterterms. We use the mode number cutoff in conjunction with the above program to compute the mass of the kink up to and including the next to the leading order quantum correction. We discuss the differences between the results of this procedure and the previously reported ones., Comment: 8 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:0806.0369

In this paper we compute the radiative correction to the mass of the kink in $\phi^4$ theory in 1+1 dimensions, using an alternative renormalization program. In this newly proposed renormalization program the breaking of the translational invariance and the topological nature of the problem, due to the presence of the kink, is automatically taken into account. This will naturally lead to uniquely defined position dependent counterterms. We use the mode number cutoff in conjunction with the above program to compute the mass of the kink up to and including the next to the leading order quantum correction. We discuss the differences between the results of this procedure and the previously reported ones., Comment: 8 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:0806.0369

© 2017, Kowsar Corp.Background: The natural history of chronic hepatitis B (CHB) infection is divided into different phases including immune tolerance (IT), immune clearance (or immune active [IA]), inactive carrier (IC), and reactivation. Despite utilizing high-throughput data, the distinct immunological mechanisms of these phases have been insufficiently investigated. Objectives: The aim of the present study was to determine candidate disease-associated genes and significantly altered biological processes for each phase of CHB infection. Methods: The gene expression profiles of 83 CHB patients (22 IT, 50 IA, and 11 IC phases) were obtained from gene expression omnibus (GEO dataset: GSE65359) and analyzed by bioinformatics tools. Several plugins of Cytoscape software were used to construct protein-protein interaction (PPI) networks and measure their topological properties. Subsequently, functional annotation and signaling pathway enrichment were carried out using the database for annotation, visualization and integrated discovery (DAVID) and Kyoto encyclopedia of genes and genomes (KEGG). Results: 449 and 452 deregulated genes were identified in IT-IA and IA-IC patients, respectively. Gene ontology and KEGG pathway analyses showed that several immune response-associated genes and signaling pathways (i.e. cytokine-cytokine receptor interaction, chemokine signaling pathway and T cell receptor signalling pathway) were upregulated in the IA phase, but downregulated in the IC phase. The LCK (encoding a tyrosine kinase) was determined as the most important hub gene of both constructed PPI networks. Furthermore, other immune response-associated genes such as CXCR3, VCAN, MYC, and STAT1 were found to be the important hub genes in clinical phases of CHB. Conclusions: The immune response-related pathways were found to be up and downregulated in the immune clearance phase and inactive carrier phase of CHB, respectively. The LCK hub gene might help the pathogenesis of differen

© 2017, Kowsar Corp.Background: The natural history of chronic hepatitis B (CHB) infection is divided into different phases including immune tolerance (IT), immune clearance (or immune active [IA]), inactive carrier (IC), and reactivation. Despite utilizing high-throughput data, the distinct immunological mechanisms of these phases have been insufficiently investigated. Objectives: The aim of the present study was to determine candidate disease-associated genes and significantly altered biological processes for each phase of CHB infection. Methods: The gene expression profiles of 83 CHB patients (22 IT, 50 IA, and 11 IC phases) were obtained from gene expression omnibus (GEO dataset: GSE65359) and analyzed by bioinformatics tools. Several plugins of Cytoscape software were used to construct protein-protein interaction (PPI) networks and measure their topological properties. Subsequently, functional annotation and signaling pathway enrichment were carried out using the database for annotation, visualization and integrated discovery (DAVID) and Kyoto encyclopedia of genes and genomes (KEGG). Results: 449 and 452 deregulated genes were identified in IT-IA and IA-IC patients, respectively. Gene ontology and KEGG pathway analyses showed that several immune response-associated genes and signaling pathways (i.e. cytokine-cytokine receptor interaction, chemokine signaling pathway and T cell receptor signalling pathway) were upregulated in the IA phase, but downregulated in the IC phase. The LCK (encoding a tyrosine kinase) was determined as the most important hub gene of both constructed PPI networks. Furthermore, other immune response-associated genes such as CXCR3, VCAN, MYC, and STAT1 were found to be the important hub genes in clinical phases of CHB. Conclusions: The immune response-related pathways were found to be up and downregulated in the immune clearance phase and inactive carrier phase of CHB, respectively. The LCK hub gene might help the pathogenesis of differen