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In this paper, we have demonstrated that resonant activation (RA) is possible even in a thermodynamically closed system where the particle experiences a random force and a spatio-temporal frictional coefficient from the thermal bath. For this stochastic process, we have observed a hallmark of RA phenomena in terms of a turnover behavior of the barrier-crossing rate as a function of noise correlation time at a fixed noise variance. Variance can be fixed either by changing temperature or damping strength as a function of noise correlation time. Our another observation is that the barrier crossing rate passes through a maximum with increase in coupling strength of the multiplicative noise. If the damping strength is appreciably large, then the maximum may disappear. Finally, we compare simulation results with the analytical calculation. It shows that there is a good agreement between analytical and numerical results. [ABSTRACT FROM AUTHOR]

In this present research, a superhydrophobic cotton fabric exhibiting a water contact angle of 155.2° has been prepared via dip‐coating technique involving silica nanoparticle deposition followed by silane hydrophobization. Interestingly, the mirror‐like phenomenon was also observed at the interface between was and modified cotton fabric. The surface morphology and microstructure of the modified fabrics were characterized by scanning electron microscope (SEM) and energy dispersive x‐ray spectroscopy (EDX). Fourier transform infrared spectroscopy (FTIR) was performed for functional group detection on a modified cotton surface. For practical applications, the washing durability was characterized by measuring contact angle values before and after washing cycles. Besides this, the durability of the superhydrophobic cotton fabric was measured under different harsh environmental conditions such as highly acidic, neutral, and highly basic environment. After each measurement, water contact angles and sliding angles were measured for dynamic stabilities. Again the modified coated cotton fabric showed strong resistance to the various organic solvents. Along with the above studies, the physical and mechanical durability of the coated fabric was also measured for both industrial and household importance. [ABSTRACT FROM AUTHOR]

A simple pyridine-dicarbohydrazide based colorimetric and fluorometric chemosensor L was designed and synthesized for Al3+ ion sensing in organo aqueous solution. In the presence of Al3+ ions, probe L exhibited visible color changes and fluorescence enhancement (20-fold) due to Al3+ induced chelation-enhanced fluorescence (CHEF) effects. Chemosensor L revealed high selectivity toward Al3+ ions by "turn-on" fluorescence among the other competitive metal ions examined with a detection limit of 0.8 μM. Probe L was found to bind with Al3+ ions in a 1 : 2 (probe : metal) stoichiometric fashion, with an association constant (Ka) of 4.26 × 104 M−2. In addition, DFT and TDDFT calculations were carried out to recognize the binding nature and electronic properties of probe L and its Al-complex. Furthermore, the in situ prepared [L–Al] complex was able to detect HF2− anions via a metal displacement strategy. The bioimaging application of Al3+ and HF2− was implemented in living human liver cancer cells (Hep G2). [ABSTRACT FROM AUTHOR]

The present paper examines the impact of social protection programmes on poverty and inequality in the backward region of West Bengal. The benefits from social protection programmes (SPPs) have reduced the incidence of poverty to the extent of 3.7 percentage points. It seems that in the case of relatively less poor households, the decreasing rate of poverty gap (PG) and square poverty gap (SPG) are less than in relatively poorer households. That indicates that relatively less poor households are more deprived (especially, double deprived) than relatively more poor households. The benefits of social protection programmes have also reduced the income inequality in both absolute and relative senses. In addition, the income of relatively poorer households has increased to a greater extent than of relatively less poor households. Absolute inequality in the presence of social protection is larger than absolute inequality in its absence. The study suggests that social protection programmes can be used as important tools for reducing inequality in the backward region of West Bengal. [ABSTRACT FROM AUTHOR]

We consider a system of Brownian particles confined in a two-dimensional bilobal enclosure whose walls are driven in time periodically by an external perturbation. The response of the particles under shape modulation is characterized by a relaxational delay which results in a non-vanishing area of the response function-field loop, response function being the integrated probability of residence of the particles in any of the lobes. This phenomenon is an entropic analogue of dynamical hysteresis, which vanishes in the quasi-static limit. The hysteresis loop area depends on temperature, strength of modulating field, and the geometrical parameters of the enclosure and exhibits a turnover as a function of frequency of the field. [ABSTRACT FROM AUTHOR]

We consider the motion of Brownian particles confined in a two-dimensional symmetric bilobal enclosure with uneven cross section. Varying cross section of the confinement results in an effective entropic potential in reduced dimension. By employing two external noise forces, one additive and another multiplicative along x direction, we demonstrate that a correlation between them causes a symmetry breaking of entropic stability, i.e., a difference in relative stability of two lobes. This leads to an asymmetric localization of population in the stationary state. A two-state model is proposed to explain the asymmetric localization of population due to entropic diffusion. [ABSTRACT FROM AUTHOR]

We consider a system of Brownian particles confined in a two-dimensional bilobal enclosure. Varying cross-section of the confinement results in an effective entropic potential in reduced dimension. We show that the system may undergo an entropic noise-induced transition when the shape of the stationary probability density changes qualitatively from bimodal to trimodal type under the influence of a multiplicative noise. [ABSTRACT FROM AUTHOR]

Varying cross section of confinement of a Brownian particle in two or higher dimensions results in an effective entropic barrier in reduced dimension. When the boundaries are subjected to periodic modulation, it is possible to observe a resonance of the mean first passage time between the lobes of a bilobal confined system as a function of the modulating frequency of the walls of the enclosure. The entropic resonant activation and the associated features, which are characteristic of the shape and size of the confinement, are amenable to a theoretical analysis in terms of a two-state model. [ABSTRACT FROM AUTHOR]

Recent advancement of experimental techniques at the single molecule level has demonstrated how an external load affects a chemical reaction which controls the transport of biological motor proteins. Majority of these studies are concerned with thermodynamically open systems. We have examined a prototype model reaction in terms of inertial Brownian motion of a particle in a force field subjected to an overdamped motion of a viscous load coupled harmonically to the particle. A general analytical expression for the rate constant has been derived to demonstrate that depending on the strength of harmonic coupling and drag coefficient of the load a Kramers-like turnover can be realized in the spatial diffusion-limited regime. The turnover reduces to a crossover between the two states characterized by zero-load and finite load conditions. [ABSTRACT FROM AUTHOR]

Several years ago Zwanzig considered the diffusion in a potential that is spatially rough due to hierarchical structure of protein. We extend this idea to the overdamped Brownian dynamics in a one-dimensional periodic and rough ratchet potential. A general expression is obtained for the effective current at the steady state. Variation in both current and efficiency has been studied with respect to the amplitude of the roughness and an external nonequilibrium, nonthermal driving force. It has been shown that roughness hinders current quite significantly. Our analysis is corroborated by detailed numerical simulations and may be useful in the context of laser switching of current through molecular wires. [ABSTRACT FROM AUTHOR]

The Census Authority of India usually provides data regarding the nature of a few urbane characteristics for all the village units and thereby classifies a place as Census Town, which is considered as the lowest unit of urbanization. From the perspective of urbanization, regions of any state, consisting of blocks can be classified as economically advanced or economically backward on the basis of existence of Census Towns in it as urban places are likely to bring more prosperity in terms of standard of living. However, proper assessment of urbanization in a single measurement scale, of all village units of a particular block is not done so far. An attempt in that direction is made in this article through construction of a Generalized Urbanization Index (GUI) for all the village units of some blocks, selected through systematic-stratified sampling, from three major districts of Paschim Medinipur, Bankura and Purulia, which are known as 'so called' backward regions. The proposed GUI for a census-unit is constructed with two components - the town criteria index and the amenities index and the relative weights of both the component-indices and the underlying dimension indices are determined through the application of Iterative Average Correlation Method indicating some movement towards actuality in comparison to prevailing two other methods of weight determination - the Equal Weights Principle and the Principal Component Analysis. [ABSTRACT FROM AUTHOR]