Nanoscale Structure and Elasticity of Pillared DNA Nanotubes

We present an atomistic model of pillared DNA nanotubes (DNTs) and their elastic properties which will facilitate further studies of these nanotubes in several important nanotechnological and biological applications. In particular, we introduce a computational design to create an atomistic model of a 6-helix DNT (6HB) along with its two variants, 6HB flanked symmetrically by two double helical DNA pillars (6HB+2) and 6HB flanked symmetrically by three double helical DNA pillars (6HB+3). Analysis of 200 ns all-atom simulation trajectories in the presence of explicit water and ions shows that these structures are stable and well behaved in all three geometries. Hydrogen bonding is well maintained for all variants of 6HB DNTs. We calculate the persistence length of these nanotubes from their equilibrium bend angle distributions. The values of persistence length are ~10 {\mu}m, which is 2 orders of magnitude larger than that of dsDNA. We also find a gradual increase of persistence length with an increasing number of pillars, in quantitative agreement with previous experimental findings. To have a quantitative understanding of the stretch modulus of these tubes we carried out nonequilibrium Steered Molecular Dynamics (SMD). The linear part of the force extension plot gives stretch modulus in the range of 6500 pN for 6HB without pillars which increases to 11,000 pN for tubes with three pillars. The values of the stretch modulus calculated from contour length distributions obtained from equilibrium MD simulations are similar to those obtained from nonequilibrium SMD simulations. The addition of pillars makes these DNTs very rigid.Comment: Published in ACS Nan

Studies on antitussive effect of Tectona grandis roots using a cough model induced by sulfur dioxide gas in guinea pigs.

Objectives: Anti-tussive drugs are among the most widely used medications world wide; however no new class of drugs has been introduced into the market by keeping this point in mind. This attempt is made by testing a root of a well known timber tree Tectona grandis. Materials and methods: Here in, we have analyzed the polar compounds of Tectona grandis roots using chemical and biological methods. In this study, in vivo antitussive activity of root extracts (methanol and water) of Tectona grandis Linn. f. (Verbenaceae) was evaluated using a cough model induced by sulfur dioxide gas in rats. Results and Discussion: Treatment with aqueous extract and methanol extract at 500 mg/kg p.o. dose level showed more anti-tussive effect as compared with the dose level of 250mg/kg p.o. Differences between means were assessed by one way analysis of variance (ANOVA),followed by Dunnett’s test using sigma stat software. Both the extracts (methanol and water) significantly (P<0.05) suppressed the asthmas at the dose level of 500mg/kg.Phytochemical tests showed that methanol and water extracts tested positive for carbohydrates, reducing sugars, alkaloids, glycosides, flavonoids, sterols and saponins. Conclusion: This study provides a scientific basis on ethno medical uses of this plant. Further exploration in drug development of anti-tussives from Tectona grandis can focus on the purity activity relationships (PAR studies).

Controlling the size distribution of nanoparticles through the use of physical boundaries during laser ablation in liquids

A simple, yet effective method of controlling the size and size distributions of nanoparticles produced as a result of laser ablation of target material is presented. The method employs the presence of physical boundaries on either sides of the ablation site. In order to demonstrate the potential of the method, experiments have been conducted with copper and titanium as the target materials that are placed in two different liquid media (water and isopropyl alcohol). The ablation of the target material immersed in the liquid medium has been carried out using an Nd:YAG laser. Significant differences in the size and size distributions are observed in the cases of nanoparticles produced with and without confining boundaries. It is seen that for any given liquid medium and the target material, the mean size of the nanoparticles obtained with the boundary-fitted target surface is consistently higher than that achieved in the case of open (flat) targets. The observed trend has been attributed to the plausible role(s) of the confining boundaries in prolonging the thermalisation time of the plasma plume. In order to ascertain that the observed differences in sizes of the nanoparticles produced with and without the presence of the physical barriers are predominantly because of the prolonged thermalisation of the plasma plume and not due to the possible formation of oxide layer, select experiments with gold as the target material in water have also been performed. The experiments also show that, irrespective of the liquid medium, the increase in the mean size of the copper-based nanoparticles due to the presence of physical boundaries is relatively higher than that observed in the case of titanium target material under similar experimental conditions.Comment: 24 pages, 9 figures, a part of this work has been published in Photonics Prague 2017, (Proc. SPIE 10603, Photonics, Devices, and Systems VII, 1060304) titled "A novel method for fabrication of size-controlled metallic nanoparticles

Garud Survey: A Case of Improving Safety and Transparency in Mining Operations Using Drone Technology

SAI Minerals Pvt. Limited (SAI Minerals), a renowned company engaged in mining cement-grade limestone and manufacturing cement in Rajasthan, India, has been grappling with recurring survey reconciliation and safety issues across its mining operations. Additionally, in compliance with new government regulations, they are now required to conduct aerial surveys and submit digital images and survey reports to the Indian Bureau of Mines (IBM). SAI Minerals sought a permanent solution to these challenges and approached Garud Survey Private Limited (Garud Survey), a technology-driven surveying agency. SAI Minerals recognized that these issues not only impacted their production but also tarnished the company\u27s reputation in the mining industry due to frequent accidents. Garud Survey recommended that the best approach to address the problem was to make the survey process faster and more accurate, enabling all stakeholders to have a clear and up-to-date view of the operational status. Garud Survey proposed the implementation of cutting-edge technology to identify and address the root cause of the problem. This case further explores the application of system analysis and design to the adoption and implementation of the latest technology in a real-world use case, as well as the challenges associated with managing change

Nonisothermal crystallization kinetics and microstructure evolution of calcium lanthanum metaborate glass

This paper reports results on the crystallization kinetics of 35.5CaO-7.25La(2)O(3)-57.25B(2)O(3) glass under nonisothermal conditions based on the studies carried out from the differential thermal analysis upon using various well-established models. The crystalline phases formed during the optimized ceramization process have been confirmed from the X-ray diffraction. The activation energies of the first (formation of CaLaB(7)O(13)) and second (formation of LaBO(3)) crystallization events have been estimated using the conventional methods of Kissinger, Augis-Bennett, Ozawa, and Matusita, and the results are found to be in good agreement with each other. The Avrami exponents that are determined by these models for the crystallization of CaLaB(7)O(13) and LaBO(3) are found to be in the range of (1.81-2.35) and (4.03-4.65), respectively. This indicates that the formation of CaLaB(7)O(13) is dominated by a surface crystallization, whereas LaBO(3) is formed by three-dimensional bulk crystallization with an increased rate of nucleation. This observation is further validated by microstructural investigation, which shows the formation of CaLaB(7)O(13) phase as a surface layer and a bulk crystallization of LaBO(3) in optimally ceramized samples

Orofacial manifestations of achondroplasia

Achondroplasia (Online Mendelian Inheritance in Man [OMIM] 100800), is considered as a form of skeletal dysplasia dwarfism that manifests with stunted stature and disproportionate limb shortening. Achondroplasia is of special interest in the field of dentistry because of its characteristic craniofacial features which include relative macrocephaly, depressed nasal bridge and maxillary hypoplasia. Presence of large head, implanted shunt, airway obstruction and difficulty in head control requires special precautions during dental management. The current case report highlights the orofacial manifestations of Achondroplasia in a young pediatric patient, along with the multidisciplinary treatment (including the dental treatment) done for the patient which also might help the general practitioners in better understanding of the condition

Evaluation of the accuracy, precision and validity of hydrophylic vinyl polysiloxane impression material for bite mark analysis

The present study was undertaken to assess the accuracy, precision and validity of hydrophilic Vinyl Poly Siloxane [VPS] impression material for bite mark documentation and analysis. Medium body VPS impressions of maxillary and mandibular anterior teeth among thirty subjects were taken and dental stone casts prepared. Hollow volume overlays were made and metric analysis was done using advanced imaging software like Adobe Photoshop - 9 and Image J. These values were compared to the measurements taken from bite mark impressions of the same 30 individuals on wax wafers using light body VPS material. The mean differences in the parameters measured by the different techniques were compared using Intra Class Correlation Coefficients [ICCC]. Additionally validity parameters such as sensitivity, specificity, positive and negative predictive value were computed

Evaluation of wound healing potential of methanolic Azadirachtaindica leaves extract in normal and diabetic rats

The present study was undertaken to evaluate the effect of Azadirachta indica leaves extract on wound healing activity in normal and streptozotocin-induced diabetic rats. Methanolic extract ointment was applied on excised wounds in healthy non diabetic and streptozotocin induced diabetic rats. This exhibited significant increase in mean percentage wound contraction and tensile strength in excision and dead Space wound models respectively, in both normal and diabetic rats when compared with control. The extract promoted wound contraction, reduced the wound closure time and induced proliferation of fibroblast as well as angiogenesis and re-epithelialization. Keywords: Wound Healing, Azadirachta indica, Tensile strength, wound contractio