Mathematical and numerical model to study two-dimensional free flow isoelectric focusing

Even though isoelectric focusing (IEF) is a very useful technique for sample concentration and separation, it is challenging to extract separated samples for further processing. Moreover, the continuous sample concentration and separation are not possible in the conventional IEF. To overcome these challenges, free flow IEF (FFIEF) is introduced in which a flow field is applied in the direction perpendicular to the applied electric field. In this study, a mathematical model is developed for FFIEF to understand the roles of flow and electric fields for efficient design of microfluidic chip for continuous separation of proteins from an initial well mixed solution. A finite volume based numerical scheme is implemented to simulate two dimensional FFIEF in a microfluidic chip. Simulation results indicate that a pH gradient forms as samples flow downstream and this pH profile agrees well with experimental results validating our model. In addition, our simulation results predict the experimental behavior of pI markers in a FFIEF microchip. This numerical model is used to predict the separation behavior of two proteins (serum albumin and cardiac troponin I) in a two-dimensional straight microchip. The effect of electric field is investigated for continuous separation of proteins. Moreover, a new channel design is presented to increase the separation resolution by introducing cross-stream flow velocity. Numerical results indicate that the separation resolution can be improved by three folds in this new design compare to the conventional straight channel design.     

Hyperhomocysteinemia, as an Independent Risk Factor for Retinal Venous Occlusion in an Indian Population

Total plasma homocysteine was analysed in 64 cases of retinal vein occlusion (RVO) of which 24 cases of central retinal vein occlusion (CRVO) and 40 cases of branch retinal vein occlusion (BRVO) and compared with 45 age and sex matched control. Homocysteine was significantly increased in RVO cases in respect to control (P < 0.001). Analysis also revealed that prevalence of rise of plasma homocysteine was more in cases of CRVO (OR = 13) than that of BRVO (OR = 5.03).     

Āryabhata and axial rotation of earth

In the first part of this series, we discussed the celestial sphere and Aryabhata’s principle of axial rotation; in this part we shall discuss in detail the concept of sidereal day and then mention Aryabhata’s computations on the duration of sidereal day.     

Repertoires of collective action in an “IT City”: Urban civil society negotiations of offline and online spaces in Bangalore

This paper examines the ways in which two Internet-based civil society groups, Hasiru Usiru and Praja, negotiate online and offline spaces of collective action in Bangalore, India’s “IT City.” Based on ethnographic research, the study extends collective action theory through an examination of communicative interactions and experiences of urban civil society actors in a developing country. The paper highlight factors that impede and support collective actions, including attitudes toward the Internet as a tool for democratic engagement, ideological motivations, and perceptions of identity and membership, among others. Such a line of inquiry is significant in highlighting the possibilities of ICTs for collective action, while simultaneously avoiding the tendency to inflate and overestimate their capacity to produce social change.     

GTR component of planetary precession

Even as the theory of relativity is more than a hundred years old, it is not within easy reach of undergraduate students. These students have an insatiable urge to learn more about it even if the full machinery of the tools required to study the same is not within their comfortable reach. The recent detection of gravitational waves has only augmented their enthusiasm about the General Theory of Relativity (GTR), developed just over a hundred years now, encapsulated in Einstein’s Field Equations. The GTR provided a consistent formulation of the theory of gravity, removed the anomalies in the Newtonian model, and predicted spectacular natural phenomena which eventual experiments have testified to. This pedagogical article retraces some of the major milestones that led to the GTR and presents a simple numerical simulation of the GTR advance of the perihelion of planetary motion about the sun.     

The influence of warning messages on the public's perception of substance use: A theoretical framework

We bring different theories together to develop a theoretical framework that helps to understand how early warning messages about (new) dangerous drugs can influence the public's perception of substance use. We bring together the agenda setting theory, framing theory, dual processing theory, social learning theory, health belief model, theory of planned behavior, and cultivation theory in order to explain how warning messages diffused through the mass media can have an impact on the receivers' perceptions. Based on these insights we construct the Integrated Media Effect Framework (IMFE) that takes into account the role of cultural and structural contexts in the realm of early warning systems (EWS). Ultimately, this framework provides valuable guidelines for conceptualizing EWS and for developing applications by governments.     

Hunting in groups

The dynamics of group chase-and-escape have attracted many physicists. In this article, we highlight the biological behaviors and the underlying mathematical rules and physical laws involved during the process of hunting in groups. We discuss some recently proposed stochastic models for such a system, which reveal various universal statistical features and show how slight variation of the behavioral rules or the interaction parameters can lead to very different statistical behaviors. A number of possible challenging questions that might lead to the development of a more life-like model for this novel enthralling dynamical problem are addressed.     

Effect of integrating IoT courses at the freshman level on learning attitude and behaviour in the classroom

Education and Information Technologies - As a technology the effect of the Internet of Things (IoT) is so strong that it has changed the way of living. The transition is also apparent in the field...