Investigation of the dynamical slowing down process in soft glassy colloidal suspensions: comparisons with supercooled liquids

The primary and secondary relaxation timescales of aging colloidal suspensions of Laponite are estimated from intensity autocorrelation functions obtained in dynamic light scattering (DLS) experiments. The dynamical slowing down of these relaxation processes are compared with observations in fragile supercooled liquids by establishing a one-to-one mapping between the waiting time since filtration of a Laponite suspension and the inverse of the temperature of a supercooled liquid that is rapidly quenched towards its glass transition temperature. New timescales, such as the Vogel time and the Kauzmann time, are extracted to describe the phenomenon of dynamical arrest in Laponite suspensions. In results that are strongly reminiscent of those extracted from supercooled liquids approaching their glass transitions, it is demonstrated that the Vogel time calculated for each Laponite concentration is approximately equal to the Kauzmann time, and that a strong coupling exists between the primary and secondary relaxation processes of aging Laponite suspensions. Furthermore, the experimental data presented here clearly demonstrates the self-similar nature of the aging dynamics of Laponite suspensions within a range of sample concentrations.Comment: 30 pages, includes supporting informatio

The Linearly Independent Non Orthogonal yet Energy Preserving (LINOEP) vectors

It is well known that, in any inner product space, a set of linearly independent (LI) vectors can be transformed to a set of orthogonal vectors, spanning the same space, by the Gram-Schmidt Orthogonalization Method (GSOM). In this paper, we propose a transformation from a set of LI vectors to a set of LI non orthogonal yet energy (square of the norm) preserving (LINOEP) vectors in an inner product space and we refer it as LINOEP method. We also show that there are various solutions to preserve the square of the norm.Comment: 6 pages, 2 figure

A Report on Gamma Radiation Induced Variation in Seed Characters of Cicer arietinum L.

Cicer arietinum L. (chickpea) is one of most popular and cheap source of plant protein and minerals worldwide. The present study was directed to induce variations in seed characters of chickpea “Vijay”, especially with reference to increase in its protein and mineral content using gamma radiations as mutagenic agent. M2 population of Cicer arietinum L. “Vijay” after post-harvest analysis revealed that 300 Gy dose of gamma radiations induced significant variations in seed characters including seed size, surface texture and seed coat color. Total nine mutants were identified differing from control in seed coat colors and categorized into four groups on the basis of seed size as normal, small, bold and extra bold; two groups on the basis of surface texture and wrinkled or smooth surface. The seed yield of all mutants was noted as 100-seed weight, which was corresponding with seed size. The biochemical analysis of the seed mutants in the form of protein, iron and zinc content indicates that, seeds with dark colored seed coat have higher level of protein and minerals as compare to control

Matching aggregate posteriors in the variational autoencoder

The variational autoencoder (VAE) is a well-studied, deep, latent-variable model (DLVM) that efficiently optimizes the variational lower bound of the log marginal data likelihood and has a strong theoretical foundation. However, the VAE's known failure to match the aggregate posterior often results in \emph{pockets/holes} in the latent distribution (i.e., a failure to match the prior) and/or \emph{posterior collapse}, which is associated with a loss of information in the latent space. This paper addresses these shortcomings in VAEs by reformulating the objective function associated with VAEs in order to match the aggregate/marginal posterior distribution to the prior. We use kernel density estimate (KDE) to model the aggregate posterior in high dimensions. The proposed method is named the \emph{aggregate variational autoencoder} (AVAE) and is built on the theoretical framework of the VAE. Empirical evaluation of the proposed method on multiple benchmark data sets demonstrates the effectiveness of the AVAE relative to state-of-the-art (SOTA) methods

Emergence of a spin-liquid-like phase in quantum spin-ladder Ba2CuTeO6 with chemical substitution

Stabilization of the quantum spin liquids is vital to realize applications in spintronics and quantum computing. The unique magnetic structure of Ba2CuTeO6 comprising of coupled spin-ladders with finite inter-ladder coupling brings the system close to the quantum critical point. This opens up possibilities to stabilize unconventional magnetic phases by tailoring the intra- and inter-ladder exchange couplings. Here, we demonstrate a spin-liquid-like phase in Ba2CuTeO6 using the method of chemical substitution. We choose non-magnetic La3+ cation to substitute the Ba2+ in Ba2CuTeO6 and present signature fingerprints such as deprived magnetic transition, non-dispersive AC susceptibility, magnetic field-independent heat capacity, and broad Raman continuum supporting the emergence of a spin-liquid-like phase. We believe that an increased magnetic frustration and spin-fractionalization upon chemical substitution play a crucial role in driving such a state. In addition, temperature and magnetic field-dependent phonon response indicate the presence of magnetostriction (spin-lattice coupling) in La-doped Ba2CuTeO6, a notable property of spin-liquids

Antifungal acetylinic thiophenes from Tagetes minuta: potential biopesticide

Apart from thiophenes, which possess wide range of biocidal activity, aerial parts of Tagetes sp. contain essential oil. Oil components were reported to have antifungal activity, thus making whole plant of Tagetes very useful for exploiting as natural fungistatic agent. In the present study, Tagetes minuta grown in north western Himalayan condition were evaluated for its potential for use as antifungal agent. Flower essential oil showed minimal antifungal activity. Whereas, leaf essential oil was found signifi cant antifungal activity against three phytopathogenic fungi out of eight tested fungi. ED50 values were 165, 175 and 110 μg mL-1 against Rhizoctonia solani, Sclerotinia sclerotiorum and Sclerotium rolfsii, respectively. Thiophene rich extract of Tagetes minuta was found comparatively lesser active (ED50: 233-484 μg mL-1) than leaf essential oil against the same fungi. The present study shows that essential oil from leaves and thiophene rich extracts from marigold roots have signifi cantly good antifungal activity against a number of soil borne and foliar plant pathogens. The easy availability of these plants makes it an attractive potential candidate for development of natural fungicide