12/01/2024


This paper presents rapid photothermal actuation of light-addressable, arrayed hydrogel columns in a macroporous silicon membrane. Au nanorods are incorporated into thermo-responsive p-NIPAAm hydrogel to utilize surface plasmon-induced local heating by near-infrared light. By measuring optical transmission through the fabricated membrane structure with Au nanorod embedded hydrogel, we have demonstrated that photothermal actuation of hydrogel can be done in two-dimensional, pixel-like configuration with high spatial and temporal resolutions. Benefiting from the hydrogel volume confinement within micron-sized pores, we have achieved sub-second response time of hydrogel photothermal actuation and its repeatable photothermal actuation on highly localized illuminated area. Considering that each hydrogel column is confined within each pore and different wavelength of light can be used to induce photothermal actuation of hydrogel's deswelling characteristics by modifying physical dimensions of Au nanorods, it has a potential for optically-addressable, multiplexed drug release systems with rapid response time.COVID-19 has spread around the world since December 2019, creating one of the greatest pandemics ever witnessed. According to the current reports, this is a situation when people need to be more careful and take the precaution measures more seriously, unless the condition may become even worse. Maintaining social distances and proper hygiene, staying at isolation or adopting the self-quarantine method are some of the common practices that people should use to avoid the infection. And the growing information regarding COVID-19 and its symptoms help the people to take proper precautions. In this present study, we consider an SEIRS epidemiological model on COVID-19 transmission which accounts for the effect of an individual's behavioural response due to the information regarding proper precautions. Our results indicate that if people respond to the growing information regarding awareness at a higher rate and start to take the protective measures, then the infected population decreases significantly. The disease fatality can be controlled only if a large proportion of individuals become immune, either by natural immunity or by a proper vaccine. In order to apply the latter option, we need to wait until a safe and proper vaccine is developed and it is a time-taking process. Hence, in the latter part of the work, an optimal control problem is considered by implementing control strategies to reduce the disease burden. Numerical figures show that the control denoting behavioural response works with higher intensity immediately after implementation and then gradually decreases with time. Further, the control policy denoting hospitalisation of infected individuals works with its maximum intensity for quite a long time period following a sudden decrease. As, the implementation of the control strategies reduce the infected population and increase the recovered population, so, it may help to reduce the disease transmission at this current epidemic situation.Value theory forms the bedrock of several economic paradigms. It shapes how economists think about the purpose and functioning of the system as a whole. I identify three approaches to understanding value in economics the British classical approach, exemplified by Smith and Ricardo, the neoclassical approach based on marginal utility theory, and Marxian value theory. The classical and neoclassical tradition explain exchange value by transhistorical use values. This gives rise to a conception of capitalism as a 'real economy', i.e. a system that produces goods and services for the purpose of satisfying people's needs and wants. Ecological economists adopt and extend the classical and neoclassical view, by predominantly studying a 'real real' economy, i.e. matter-energy stocks and flows and ultimate social outcomes. https://www.selleckchem.com/products/vit-2763.html This allows an ecological critique of the economic process but fails to address underlying social drivers of ecological destruction. Marxian value theory provides a systemic (macro) understanding of value, which results in a realistic conception of capitalism as a monetary market economy. Marx's approach is the only value theory in economics that provides a fundamental critique of capitalism. I advocate a stronger integration of radical political economy and ecological economics to support social change.The detrimental effect of natural aging on mechanical properties of zinc alloys restricts their application as bioresorbable medical implants. In this study, aging of Zn-0.05Mg alloy and the effect of 0.5 Cu and 0.1 Mn (in weight percent) addition on the microstructure and tensile properties were studied. The alloys were cold rolled, aged and annealed; aiming to investigate the effects of precipitates and grain size on the mechanical properties and their stability. TEM analysis revealed that in ultrafine-grained binary Zn-0.05Mg alloy, the natural aging occurred due to the formation of nano-sized Mg2Zn11 precipitates. After 90 days of natural aging, the yield strength and ultimate tensile strength of Zn-0.05Mg alloy increased from 197±4 MPa and 227±5 MPa to 233±8 MPa and 305±7 MPa, respectively, while the elongation was drastically reduced from 34±3% to 3±1%. This natural aging was retarded by adding the third element at either 0.1Mn or 0.5Cu quantities, which interacted with Mg in Zn solid solution and impeded the formation of Mg2Zn11 precipitates. The addition of Cu and Mn elements increased alloy's strength, ductility, and its mechanical stability at a room temperature. The measured tensile strength and elongation were 274±5 MPa and 41±1% for Zn-0.1Mn-0.05Mg and 312±2 MPa and 44±2% for Zn-0.5Cu-0.05Mg, respectively. Annealing the alloys at elevated temperatures caused increase in both grain size and dissolution of secondary phases, and both affected alloy deformation mechanisms.A mathematical approach is introduced for predicting quantized resistances in graphene p-n junction devices that utilize more than a single entry and exit point for electron flow. Depending on the configuration of an arbitrary number of terminals, electrical measurements yield nonconventional, fractional multiples of the typical quantized Hall resistance at the v = 2 plateau (RH ≈ 12906 Ω) and take the form a b R H . This theoretical formulation is independent of material, and applications to other material systems that exhibit quantum Hall behaviors are to be expected. Furthermore, this formulation is supported with experimental data from graphene devices with multiple source and drain terminals.