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Temporal control over self-assembly processes is a highly desirable attribute that is efficiently exhibited by biological systems, such as actin filaments. In nature, various proteins undergo enzymatically catalysed chemical reactions that kinetically govern their structural and functional properties. Consequently, any stimuli that can alter their reaction kinetics can lead to a change in their growth or decay profiles. This underscores the urgent need to investigate bioinspired, adaptable and controllable synthetic materials. Herein we intend to develop a general strategy for controlling the growth and decay of self-assembled systems via enzymatically coupled reactions. We achieve this by the coupling of enzymes phosphokinase/phosphatase with a bolaamphiphilic cationic chromophore (PDI) which selectively self-assembles with ATP and disassembles upon its enzymatic hydrolysis. The aggregation process is efficiently regulated by the controlled in situ generation of ATP, through enzymatic reactions. By carefully managing the ATP generating components, we realize precise control over the self-assembly process. Moreover, we also show self-assembled structures with programmed temporal decay profiles through coupled enzymatic reactions of ATP generation and hydrolysis, essentially rendering the process dissipative. This work introduces a novel strategy to generate a reaction-coupled one-dimensional nanostructure with controlled dimensions inspired by biological systems. [ABSTRACT FROM AUTHOR]

The present study focuses on the cyclic behaviour of cohesionless soil collected from the quaternary alluvium deposit at the Middle Ganga Plain (MGP). A series of strain-controlled cyclic triaxial tests have been carried out on collected soil samples at various effective confining stresses, shear strain amplitudes and motion frequencies to estimate the dynamic parameter at large strain. From the results, it has been shown that dynamic properties and liquefaction strength substantially affected by the shear strain amplitude of input motion. However, effective confining stress and motion frequency have no significant effect on dynamic properties and liquefaction strength at large strain. Regression equations have been developed for dynamic and liquefaction strength parameters for the studied soil. It has been found that the consideration of asymmetricity in the shape of hysteresis loops significantly influences the damping ratio estimation at a particular shear strain. Another novel aspect that has been presented in this study is the effect of effective confining stress on the EPWP model parameter F using a mathematical equation. The regression equation for model parameter F proposed in this study has been validated by predicting the maximum EPWP development of studied soil and other quarternary alluvium soils available worldwide. [ABSTRACT FROM AUTHOR]

The amplification of asymmetry in supramolecular polymers has recently garnered significant attention. While asymmetry amplification has predominantly been explored under thermodynamic conditions, the kinetic aspect of this process unveils intriguing observations, yet is scarcely reported in the literature. Herein, drawing inspiration from macromolecular systems, we propose a novel strategy for enhancing asymmetry in supramolecular polymers through a seed-induced supramolecular polymerization approach under kinetic conditions, employing a naphthalene diimide-derived monomer (ANSG) for template-induced supramolecular polymerization, utilizing adenosine triphosphate (ATP) and pyrophosphate (PPi) as templates. A chiral seed comprising [ANSG-ATP]S effectively amplifies the overall supramolecular asymmetry when exposed to a mixture of achiral templates (PPi) and monomers (ANSG), owing to its efficient seeding characteristics under kinetic conditions. As a result of efficient co-operativity, conversely, employing an achiral seed [ANSG-PPi]S in a mixture of chiral templates (ATP) and monomers (ANSG) results in the attenuation of asymmetry, highlighting the effective modulation achievable through the seeding approach, -an unprecedented observation in the field. Exploiting the efficient aggregation-induced emission enhancement (AIEE) of the resultant supramolecular polymers further extends the amplification and attenuation of circularly polarized luminescence (CPL) as a potential function., (© 2024 Wiley‐VCH GmbH.)

Childhood visual impairment due to refractive errors is a significant problem in school children and has a considerable impact on public health. To assess the magnitude of the problem the present study was undertaken among the school children aged 5 to 10 years in Kolkata. Detailed ophthalmological examination was carried out in the schools as well as in the Regional Institute of Ophthalmology, Kolkata. Among 2317 students examined, 582 (25.11%) were suffering from refractive errors, myopia being the commonest (n = 325; 14.02%). Astigmatism affected 91 children (3.93%). There is an increase of prevalence of refractive errors with increase of age, but it is not statistically significant (p > 0.05). There is also no significant difference of refractive errors between boys and girls.

Rhinosporidium seeberi, the causative organism causing rhinosporidiosis, also affects extranasal sites. A 1 5-year-old male presented with a conjunctival fleshy swelling near the inner canthus of the left eye. His visual acuity was within normal range. Conjunctival papilloma was the provisional diagnosis for which he was operated on. Histopathology proved to be a case of ocular rhinosporidiosis. Six months follow-up of the case showed no recurrence.