Plant Products as Biopesticides: Building On Traditional Knowledge of Vrkshayurveda: Traditional Indian Plant Science

Today there is a global search for alternatives to chemical pesticides and as part of this process there are various efforts to test the use and efficacy of natural products for pest control and crop protection. Our Centre has been involved in exploring the traditional knowledge regarding the use of natural products for pest control and crop protection. As part of this effort, we have looked at the traditional folk practices prevalent among farmers as well as information from classical literature on the subject drawn from Vrkshayurveda (traditional Indian plant science). Following this, we have carried out experiments for standardizing and field testing promising natural products by determining the precise range and kind of pests controlled by them, determining the optimum concentration where they can be effective against pests without being harmful to useful organisms and predators as well as studying their mode of action. Subsequently, we have also developed storage forms of various of these products by using methods based on Ayurveda. Studies on the stability and shelf life of these products are also being carried out through an insect rearing laboratory. Finally, we have also set up village based biopesticides units where a range of these products are being prepared thus providing valuable inputs to sustainable agriculture and a means of livelihood to rural women and farmers

Preliminary in Vitro- Investigation on Antimicrobial Activity of Mononuclear and Dinuclear Iron (III) Complexes

In vitro effect of two dinuclear and mononuclear iron complexes with different ligands was examined on Gram positive and Gram negative bacterial strains. Broad spectrum antibiotic oxytetracycline was used as control. The experiment was performed by the routine agar-diffusion method of bauer et al. and the method of  minimum  inhibitory concentrations (MICs). It was  found  that mononuclear complexes expressed antibacterial effect in vitro, especially against Gram (+) strains. The minimum inhibitory effect of Fe (NADP) Cl2 was more pronounced

Hydrogen Bond Dynamics Near A Micellar Surface: Origin of the Universal Slow Relaxation at Complex Aqueous Interfaces

The dynamics of hydrogen bonds among water molecules themselves and with the polar head groups (PHG) at a micellar surface have been investigated by long molecular dynamics simulations. The lifetime of the hydrogen bond between a PHG and a water molecule is found to be much longer than that between any two water molecules, and is likely to be a general feature of hydrophilic surfaces of organized assemblies. Analyses of individual water trajectories suggest that water molecules can remain bound to the micellar surface for more than a hundred picosecond. The activation energy for such a transition from the bound to a free state for the water molecules is estimated to be about 3.5kcal/mole.Comment: 12 pages. Phys. Rev. Lett. (Accepted) (2002

Nodulation and nitrogen fixation in chickpea (Cicer arietinum L.) under salt stress

The effects of salt stress on the growth, nodulation and N accumulation during the vegetative phase was studied in chickpea (Cicer arietinum). Growth and N accumulation were adversely affected by salinity. The larger control plants produced new nodules but the existing nodules on stressed plants grew larger than those of control plants. All plants had similar %N contents but the total plant N was less in stressed plants due to the reduced growth of these plants. Reduced plant vigour was the primary effect of salt stress and was mediated through processes other than symbiotic N fixation

The binding requirements of monkey brain lysosomal enzymes their immobilised receptor protein

The lysosomal enzyme binding protein (receptor protein) isolated from monkey brain was immobilised on Sepharose 4B and used to study the binding of brain lysosomal enzymes. The immobilised protein could bind ß-D-glucosaminidase, α-D-mannosidase, α -L-fucosidase and ß-D-glucuronidase. The bound enzymes could be eluted either at an acid pH of 4.5 or by mannose 6-phosphate but not by a number of other sugars tested. Binding could be abolished by prior treatment of the lysosomal enzymes with sodium periodate. Alkaline phosphatase treatment of the enzymes did not prevent the binding of the lysosomal enzymes to the column but decreased their affinity, as seen by a shift in their elution profile, when a gradient elution with mannose 6-phosphate was employed. These results suggested that an 'uncovered' phosphate on the carbohydrate moiety of the enzymes was not essential for binding but can enhance the binding affinity

Examining post COVID-19 tourist concerns using sentiment analysis and topic modeling

The COVID-19 pandemic has had a destructive effect on the tourism sector, especially on tourists’ fears and risk perceptions, and is likely to have a lasting impact on their intention to travel. Governments and businesses worldwide looking to revive and revamp their tourism sector, therefore, must first develop a critical understanding of tourist concerns starting from the dreaming/planning phase to booking, travel, stay, and experiencing. This formed the motivation of this study, which empirically examines the tourist sentiments and concerns across the tourism supply chain. Natural Language Processing (NLP) using sentiment analysis and Latent Dirichlet Allocation (LDA) approach was applied to analyze the semi-structured survey data collected from 72 respondents. Practitioners and policymakers could use the study findings to enable various support mechanisms for restoring tourist confidence and help them adjust to the ’new normal.

Non-Quasinormal Modes and Black Hole Physics

The near-horizon geometry of a large class of extremal and near-extremal black holes in string and M theory contains three-dimensional asymptotically anti-de Sitter space. Motivated by this structure, we are led naturally to a discrete set of complex frequencies defined in terms of the monodromy at the inner and outer horizons of the black hole. We show that the correspondence principle, whereby the real part of these ``non-quasinormal frequencies'' is identified with certain fundamental quanta, leads directly to the correct quantum behavior of the near-horizon Virasoro algebra, and thus the black hole entropy. Remarkably, for the rotating black hole in five dimensions we also reproduce the fractionization of conformal weights predicted in string theory.Comment: 4 pages, revtex4; v2: reference added; v3: more references, minor typo corrected; v4: minor rewording to adjust size (ugh!); v5: some small clarifications at referees' suggestio

Effects of prolonged exposure to low dose metformin in thyroid cancer cell lines

© Ivyspring International Publisher. Background: Thyroid cancer is generally associated with an excellent prognosis, but there is significant long-term morbidity with standard treatment. Some sub-types however have a poor prognosis. Metformin, an oral anti-diabetic drug is shown to have anti-cancer effects in several types of cancer (breast, lung and ovarian cancer). The proposed mechanisms include activation of the Adenosine Mono-phosphate-activated Protein Kinase (AMPK) pathway and inhibition of the mTOR pathway (which promotes growth and proliferation). By inhibiting hepatic gluconeogenesis and increasing glucose uptake by muscles, metformin decreases blood glucose and circulating Insulin levels. Aims: Explore the effect of metformin on the growth and proliferation of thyroid cancer cell lines. Methods: The effects of metformin on thyroid cancer cell lines (FTC-133, K1E7, RO82-W-1, 8305C and TT) and normal thyroid follicular cells (Nthy-ori 3-1) were investigated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay for cell proliferation; clonogenic assays FACS analysis for apoptosis and cell cycle, H2A.X phosphorylation (γH2AX) assay for DNA repair and scratch assay for cell migration. Results: Metformin inhibited cell proliferation and colony formation at 0.03 mM and above and inhibited cell migration at 0.3 mM. At concentrations of 0.1 mM and above metformin increased the percentage of apoptotic cells and induced cell cycle arrest in G0/G1 phase at minimum concentration of 0.3 mM. Unlike previous reports, no effect on DNA repair response was demonstrated. Conclusion: Metformin suppressed growth of all thyroid cancer cell lines, at concentrations considered to be within in the therapeutic range for diabetic patients on metformin (<0.3 mM)

Quantum geometry and gravitational entropy

Most quantum states have wavefunctions that are widely spread over the accessible Hilbert space and hence do not have a good description in terms of a single classical geometry. In order to understand when geometric descriptions are possible, we exploit the AdS/CFT correspondence in the half-BPS sector of asymptotically AdS_5 x S^5 universes. In this sector we devise a "coarse-grained metric operator" whose eigenstates are well described by a single spacetime topology and geometry. We show that such half-BPS universes have a non-vanishing entropy if and only if the metric is singular, and that the entropy arises from coarse-graining the geometry. Finally, we use our entropy formula to find the most entropic spacetimes with fixed asymptotic moments beyond the global charges.Comment: 29 pages, 2 figures; references adde