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Lesser bandicoot rat, Bandicota bengalensis (Gray) burrows found complex with a fresh soil scoop at the entrance and ramified branches, galleries and bolt holes. Burrow length was more in light textured sandy soils, whereas burrow depth and branching were found more in heavy textured alluvial clay soils. Among the various soil properties, pH has shown a significant positive correlation with burrow depth (r = 0.51) and number of branches in a burrow (r = 0.50). Multiple linear regression analysis revealed that pH had a significant positive effect with circumference and branches, EC and bulk density with depth of the burrow, particle density and porosity with circumference of the burrow. Burrow temperature is always low over the soil and atmospheric temperatures in alluvial clay soils, but in sandy soils burrow temperature is relatively higher than soil temperature during lean period. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at the Agricultural college, Naira during rabi, 2020-21 on the control of major insect pests on sesamum viz., leafhopper Hishimonus phycitis (Distant) and whitefly Bemisia tabaci (Gennadius) and phyllody disease. The results revealed that thiamethoxam 25WG @ 0.25 g/l was very effective against both the pests with 72.2 and 50.5% reduction in incidence, respectively. Thiamethoxam was also effective against phyllody (PDI of 5.72), and gave a maximum seed yield of 6.50 q/ha and B:C ratio (1:4.7). Seed treatment with imidacloprid 17.5SL @ 5 ml/kg seed stood as the next best with B:C ratio of 1:3.7. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at the Agricultural College, Naira during rabi, 2020-21 to test the efficacy of insecticides against leaf webber and capsule borer in sesamum. The treatments included T1: Seed treatment with Imidacloprid 17.5 SL @ 5 ml/kg seed, T2: Thiamethoxam 25 WG @ 0.25 g/l, T3: Diafenthiuron 50 WP @ 1.6 g/l, T4: Pymetrozine 50 WG @ 0.6 g/l, T5: Spinosad 45 SC @ 0.33 g/l, T6: Novaluron 10 EC @ 1.0 ml/l, T7: Chlorantraniliprole 18.5 SC @ 0.3 ml/l, T8: Chlorantraniliprole 9.3% + Lambda-cyhalothrin 4.6% @ 0.5 ml/l, T9: Acephate 75 WP @ 1.5 g/l, T10: Untreated check. Research findings revealed that the Chlorantraniliprole 18.5 SC @ 0.3 ml/l was highly effective against Antigastra catalaunalis by recording the lowest larval population (1.30/plant) and lowest capsule damage (1.25%) compared to all other treatments. The next best treatments included Spinosad 45SC @ 0.33 g/l(1.68/plant), followed by Novaluron 10 EC @ 1.0 ml/l(1.78/plant) with 64.4 and 62 per cent reduction in population, respectively. [ABSTRACT FROM AUTHOR]

A field experiment was carried out at the Agricultural College Farm, Naira during rabi, 2019-20 on management of insect pests of sweet corn with special emphasis on fall army worm Spodoptera frugiperda (J E Smith). The results revealed that emamectin benzoate 5SG @0.4 g l-1 (83.19% reduction in larval incidence) followed by spinosad 45SC @ 0.3 ml l-1, chlorantraniliprole 0.4G @ 10 kg ha-1 and chlorantraniliprole 9.3%+ lambda cyhalothrin 4.6% @ 0.5 ml l-1 were significantly superior (with 80.49, 77.02 and 74.67% reduction in larval incidence, respectively). The treatments with cyantraniliprole 19.8% + thiamethoxam 19.8%FS @ 6 ml kg-1, lambda cyhalothrin 5EC @ 2ml l-1 and fipronil 0.3G @ 12 kg ha-1 were the less effective ones. Emamectin benzoate 5SG gave maximum yield of 39,716 kg ha-1 with ICB ratio of 1:22.57. [ABSTRACT FROM AUTHOR]

GAGs bind to both the monomeric and dimeric forms of CXCL8, helping to form a concentration gradient of the chemokine that facilitates the recruitment of neutrophils to an injury site and supports other biological functions. In this study, atomistic molecular dynamics simulations were conducted to investigate the binding behavior of two hexameric GAGs sulfated at two different positions, chondroitin sulfate (CS) and heparan sulfate (HS), with the monomer (SIL8) and dimer (DIL8) forms of the CXCL8 protein. The results support that the conformational diversity of CS and HS appeared to be more when binding with monomer SIL8 than dimer DIL8. CS gained more configurational entropy from glycosidic linkage flexibility when bound to SIL8 than DIL8, with a higher energy barrier, whereas HS exhibited a lower energy barrier for configurational entropy when bound to SIL8 and DIL8. The monomer SIL8 exhibited more favorable and preferential binding with GAGs compared to DIL8. Formation of hydrogen bonds with the basic amino acids of SIL8 and GAG was more rigid and required higher activation energy to break than the other identified hydrogen bondings. Water molecules involved in hydrogen bonding with GAGs, excluding those with basic amino acids of DIL8, showed longer lifetimes and slower relaxation compared to SIL8. This suggests that water-mediated interactions also favor binding of DIL8 with GAGs. Despite having more basic amino acids, DIL8 did not display stronger binding than SIL8, indicating the significant role of basic residues in stabilizing the GAG-protein interactions in the monomers. The reason could be that the greater number of nonbasic amino acids in dimeric CXCL8 stabilizes the complex by forming water-mediated hydrogen bonds, reducing the conformational preferences for binding with GAGs. In contrast, the monomeric form of CXCL8 exhibits a higher conformational preference for protein-GAG interactions.

The sulfation pattern and epimerization of the long-chain sulfated polysaccharide heparan sulfate (HS) cause structural diversity and regulate various physiological and pathological processes when binding with proteins. In this work, we performed a series of molecular dynamics simulations of three variants of the octadecasaccharide HS with varying sulfation positions in aqueous medium in their free forms and in the presence of the chemokine CXCL8 dimer. The free energy of binding depicts the sulfation at the 6-O position of GlcNAc (HS6S), and both 3-O and 6-O positions of GlcNAc (HS3S6S) of HS variants are more likely to bind with the CXCL8 dimer than the triply sulfated HS2S3S6S, which is sulfated at the 2-O position of GlcUA additionally along with 3-O and 6-O positions of GlcNAc. Binding between HS and CXCL8 was driven by electrostatic and van der Waals interactions predominantly regardless of the sulfation pattern; however, unfavorable entropic contribution suppressed the interaction between HS and CXCL8. The contribution of different amino acid residues to the binding energetics suggested that basic amino acids line up the binding site of CXCL8. This study further acknowledges the role of interfacial water that is structured and bound with HS through hydrogen bonds, exhibiting differential hydrogen bond relaxation dynamics compared to when the HS molecules are free. Moreover, this study identifies that with the increase in sulfation, the HS-water hydrogen bond relaxation occurs faster with the complexation, while the reverse trend is followed in their free forms. Significant structural adaptation of the different sulfated HS molecules, as verified from the free energy landscapes generated from various reaction coordinates, root-mean-square-deviations, end-to-end distances, including ring pucker angles, dihedral flexibility, and the high conformational entropy cost arising from the glycosidic bonds, suggests that the different sulfated variants of HS undergo significant structural transformation to bind with CXCL8. The presence of a CXCL8 dimer imposes the bound forms of HS to adopt non-linear structures with skew-boat conformations. The atomistic details of the study would help in understanding the selectivity and conformational diversity, as well as the role of solvents in the recognition of CXCL8 by different sulfated variants of HS molecules.

Replacement of carbon atoms by a heteroatom in fullerene is a promising route that enhances the electronic properties of fullerenes and results in hetero fullerene-based effective agents ensuring applications in vivid fields of the solar cell, cathode materials for batteries, etc. Towards the development of new electrolyte salts, attention has been paid to facilitating ion mobility in particular and moderate stability of the anions in addition. From the atomistic molecular dynamics simulation studies, for the first time, we uncover that the boron-containing hetero fullerene, C 59 B - anion-based LiC 59 B, and NaC 59 B salts in cyclic carbonate solvents can act as efficient electrolytes by improving the transport phenomenon of the metal ions in solution, importantly for Li + and satisfactorily for Na + as compared to their commonly used BF 4 - anion based salts. Additionally, our study revealed that apart from LiC 59 B, and NaC 59 B salts, C 58 B 2 2- based MgC 58 B 2 salt can facilitate the ionic conductivity of the electrolyte. The properties of the proposed electrolyte under an electric field and different temperatures were investigated. Some of the bulk properties of the used electrolytes to some extent were found to be improved in the presence of these salts. The first principle-based electrochemical calculations further justify the stability of the proposed anions. The initial investigation from the Reactive force-field (ReaxFF) based atomistic simulations study elucidates that LiC 59 B reduces the decomposition of the EC solvent compared to LiBF 4 and facilitates solvent stability.

The sulfation patterns and degree of sulfation of chondroitin sulfate (CS), an important class of glycosaminoglycans (GAG), and their interactions with chemokines are accountable for various diseases. To realize the underlying mechanism of such complex biological phenomena at a molecular level and their application in rational drug design, a study on conformations and dynamics of CSs is necessary. To explore this, in this study, we performed a series of atomistic molecular dynamics (MD) simulations with different sulfated variants of octadecasaccharide CS, like CS-C, CS-E, and CS-T, in their free forms and when bound to the protein chemokine CXCL8 dimer in an aqueous medium. The calculated binding free energy of CSs with the CXCL8 dimer is favorable, and the degree of sulfation favors the complexation process further with prominent hydrophobic and hydrogen-bonded interactions. We find that the recognition is associated with the configurational entropy loss of the CS molecules as calculated from the Gaussian mixture approach, which supports that the degree of sulfation regulates the process. Cluster analysis through the k -means algorithm and end-to-end distance measurement revealed that although the free CS molecules adopted linear conformations, the nonlinear conformations during binding with protein were noted. Adaptation of nonlinear forms in the bound forms is noteworthy for the less-sulfated CS-C and CS-E. Apart from favorable 4 C 1 conformations, the occasional appearance of skew-boat forms from the free-energy map of ring pucker for the GlcUA unit was observed, which remains unaffected by the sulfation. We find that during recognition, the average relaxation time of intra-CS and inter-CS-CXCL8 hydrogen bonds (HBs) is about a magnitude lesser than that of CS-water HBs, most prominent on the involvement of higher sulfated CS-T analogues. The translational motion of surrounded water molecules in CSs exhibited sublinear diffusion, and the degree of sublinearity increases around the heavily sulfated molecules due to the hindrance created by them as well as the presence of the chemokine and exhibited markedly slow heterogeneous diffusion.

Atomistic molecular dynamics simulations were performed under ambient conditions to explore the conformational features and binding affinities of hexameric glycosaminoglycans (GAGs) with chemokine Interleukin8 (IL8) in an aqueous medium. We tried to understand the role of hydrogen bonds (HBs) involving conserved water in mediating the interactions. The Luzar-Chandler model was adopted to study the kinetics of HB breaking and formation concerning different water-mediated HBs. The conformational flexibilities of bound GAGs are due to the flexible glycosidic linkages than the occasional/rare ring pucker conformation. The free energy landscape constructed with ϕ, and ψ, depicted that different conformational minima associated with the glycosidic linkage flexibility of the GAGs in bound states are separated by energy barriers. The binding affinities of IL8 towards GAGs are favored through the electrostatic and non-polar solvation interactions. 4-different types of conserved water were explored in the solvent-mediated binding of GAGs with IL8. The average lifetime of the IL8-GAG direct HB pairs was ∼ten times less than the IL8-GAG-shared water HBs. This is due to the rapid establishment of HB breaking and reformation kinetics involving water of a shared layer. We find that despite the highly negatively charged surface of GAGs, the IL8 surface populated by non-cationic amino acids could serve as a promising binding site in addition to the cationic surface of the protein., (© 2022 Wiley-VCH GmbH.)

Amino acids having basic side chains, as additives, are known to increase the stability of native-folded state of proteins, but their relative efficiency and the molecular mechanism are still controversial and obscure as well. In the present work, extensive atomistic molecular dynamics simulations were performed to investigate the hydration properties of aqueous solutions of concentrated arginine, histidine, and lysine and their comparative efficiency on regulating the conformational stability of the insulin monomer. We identified that in the aqueous solutions of the free amino acids, the nonuniform relaxation of amino acid-water hydrogen bonds was due to the entrapment of water molecules within the amino acid clusters formed in solutions. Insulin, when tested with these solutions, was found to show rigid conformations, relative to that in pure water. We observed that while the salt bridges formed by the lysine as an additive contributed more toward the direct interactions with insulin, the cation-π was more prominent for the insulin-arginine interactions. Importantly, it was observed that the preferentially more excluded arginine, compared to histidine and lysine from the insulin surface, enriches the hydration layer of the protein. Our study reveals that the loss of configurational entropy of insulin in arginine solution, as compared to that in pure water, is more as compared to the entropy loss in the other two amino acid solutions, which, moreover, was found to be due to the presence of motionally bound less entropic hydration water of insulin in arginine solution than in histidine or lysine solution.

Background: The pink bollworm is one of the most destructive pests of cotton. Transgenic cotton producing Bt toxin Cry1Ac or a combination of Cry1Ac and Cry2Ab2 has been used effectively against this pest. However, some other insects have evolved resistance to Bt toxins in the field. During the 2007-2008 and 2008-2009 seasons, pink bollworm populations in India were surveyed to evaluate their responses to Cry1Ac and seed powder containing Cry1Ac and Cry2Ab2., Results: The results provide evidence that resistance to Cry1Ac had evolved by 2008 in a population sampled from non-Bt cotton in the Amreli district of Gujarat in western India. The median lethal concentration of Cry1Ac for five-day-old larvae (LC50 ) was significantly higher for insects derived in 2008 from Amreli than for any of the other field populations tested from four locations in India. For Cry1Ac, the mean LC50 for the strain derived from Amreli in 2008 was 44 times higher than for the most susceptible population. However, for seed powder of Bollgard II containing primarily Cry2Ab2, the 2008 Amreli population was only slightly less susceptible than the most susceptible population., Conclusions: The data reported here constitute the first evidence of field-evolved resistance of pink bollworm to Cry1Ac. This initial evidence spurred more extensive evaluations during the 2009-2010 growing season, which confirmed field-evolved resistance to Cry1Ac in Amreli. The lack of cross-resistance to Cry2Ab2 suggests that plants producing this toxin are likely to be more effective against resistant populations than plants producing only Cry1Ac., (Copyright © 2011 Society of Chemical Industry.)