The kinetics of bromine exchange between p-Nitrobenzyl bromide and some ionic bromides in liquid sulphur dioxide

Thesis (Ph.D.)--Boston UniversityThe influence of the counter ion on the reactivity of a nucleophilic anion has not been extensively investigated. A survey of the literature shows that there is some evidence that the reactivity of the ionic nucleophile is modified by ionic association. This problem is intimately connected with the relationship between ion pairs which are counted by conductivity and ion pairs which are kinetically significant. The dissociation constants for a number of ionophores are known in liquid sulfur dioxide at several temperatures and it is a good ionizing solvent. Accordingly, the exchange of radiobromine between p-nitrobenzyl bromide and ionic bromides was studied in liquid sulfur dioxide (Eq. 1). [TRUNCATED

Grid emulator for wave energy converter testing

Power generation has been an ever growing exigency since the invention of electric power. The world is gradually inching away from conventional generation toward renewable generation. Advancements in renewable energy generation have been at a steady positive pace over the past few decades with different resources developing to be feasible alternatives. A smooth and gradual transition from conventional generation to predominantly renewable energy sourced generation is what the world is looking toward in the next couple of centuries. The grid emulator is a device that will facilitate the testing and development of wave energy generators, thereby enabling the inclusion of energy generated using wave power into the existing generation mix, without causing adverse effects to the host system. The grid emulator will enable testing of wave energy devices under different grid disturbances as well as provide isolation between the devices and the grid during initial testing. This thesis presents the preliminary functions planned using the grid emulator, the specifications of the device, the design details and simulation results. The grid emulator under development is currently limited to wave energy devices, however, anomalous devices could be developed for the research and development of other under developed and untapped renewable resources

Thermal Degradation of Polypropylene Pine Sawdust Composite Filaments through Successive Heating and Reprocessing

Considering the use of the new molding thermoplastic technique, where viscous filaments can be artistically or technically manipulated to create three-dimensional pieces using an extruder, this paper discusses the optimal PP/wood fiber filament preparation conditions especially the thermal degradation. Not only is it essential to know the best processing conditions of the composites but also gain durability and/or advantageous color change when the final products made with viscous filaments are subjected to thermal treatments. Very few papers have been published on polypropylene-pine wood filament composites and the thermal degradation of such filaments. This paper presents the preparation and characterization of filament composites using 5, 10, and 20wt.% pine sawdust with a compatibilizer obtained by hot molding through the use of an extruder, and discusses the effect of both drying time and temperature on the prepared filament composites to understand thermal degradation when subjected to 60°C and/or 120°C. Prepared filament composites are characterized for physical (density, water absorption, and crystallinity), thermal and tensile properties besides their morphology along with fractography. X-ray diffraction results confirmed the data obtained in thermal studies indicating that increased fiber content decreased both the crystallinity and the thermal resistance while decreasing the melting temperature of the filament composites. Fractographic studies revealed low adhesion between the sawdust and the matrix, evidenced by the presence of loose and some unattached sawdust particles in some composites, thus, supporting the observed low strength in these composites, besides the influence of drying time and temperature on the mechanical properties of the composites

Mechanical properties of boehmeria nivea natural fabric reinforced epoxy matrix composite prepared by vacuum-assisted resin infusion molding

Natural lignocellulosic fibers and corresponding fabrics have been gaining notoriety in recent decades as reinforcement options for polymer matrices associated with industrially applied composites. These natural fibers and fabrics exhibit competitive properties when compared with some synthetics such as glass fiber. In particular, the use of fabrics made from natural fibers might be considered a more ecient alternative, since they provide multidirectional reinforcement and allow the introduction of a larger volume fraction of fibers in the composite. In this context, it is important to understand the mechanical performance of natural fabric composites as a basic condition to ensure ecient engineering applications. Therefore, it is also important to recognize that ramie fiber exhibiting superior strength can be woven into fabric, but is the least investigated as reinforcement in strong, tough polymers to obtain tougher polymeric composites. Accordingly, this paper presents the preparation of epoxy composite containing 30 vol. % Boehmeria nivea fabric by vacuum-assisted resin infusion molding technique and mechanical behavior characterization of the prepared composite. Obtained results are explained based on the fractography studies of tested samples

Insight into Recent Progress and Perspectives in Improvement of Antioxidant Machinery upon PGPR Augmentation in Plants under Drought Stress: A Review

Agriculture has a lot of responsibility as the rise in the world’s population demands more food requirements. However, more than one type of biotic and abiotic stress continually impacts agricultural productivity. Drought stress is a major abiotic stress that significantly affects agricultural productivity every year as the plants undergo several morphological, biochemical, and physiological modifications, such as repressed root and shoot growth, reduced photosynthesis and transpiration rate, excessive production of reactive oxygen species (ROS), osmotic adjustments, and modified leaf senescence regulating and stress signaling pathways. Such modifications may permanently damage the plants; therefore, mitigation strategies must be developed. The use of drought resistant crop cultivars is more expensive and labor-intensive with few advantages. However, exploiting plant growth promoting rhizobacteria (PGPR) is a proven alternative with numerous direct and indirect advantages. The PGPR confers induced systemic tolerance (IST) mechanisms in plants in response to drought stress via multiple mechanisms, including the alteration of root architecture, maintenance of high relative water content, improvement of photosynthesis rate, production of phytohormones, exopolysaccharides, ACC deaminase, carotenoids and volatiles, induction of antioxidant defense system, and alteration in stress-responsive gene expression. The commercial application of PGPR as bioinoculants or biostimulants will remain contingent on more robust strain selection and performance under unfavorable environmental conditions. This review highlights the possible mechanisms of PGPR by activating the plant adaptive defense systems for enhancing drought tolerance and improving overall growth and yield

FPGA ARCHITECTURE FOR 2D DISCRETE FOURIER TRANSFORM BASED ON 2D DECOMPOSITION FOR LARGE-SIZED DATA

ABSTRACT Applications based on Discrete Fourier Transforms (DFT) are extensively used in various areas of signal and digital image processing. Of particular interest is the two-dimensional (2D) DFT which is more computation-and bandwidth-intensive than the one-dimensional (ID) DFT. Traditionally, a 2D DFT is computed using Row-Column (RC) decomposition, where ID DFTs are computed along the rows followed by ID DFTs along the columns. Both application specific and reconfigurable hardware have been used for high-performance implementations of 2D DFT. However, architectures based on RC decomposition are not efficient for large input size data due to memory bandwidth constraints. In this paper, we propose an efficient architecture to implement the 2D DFT for largesized input data based on a novel 2D decomposition algorithm. This architecture achieves very high throughput by exploiting the inherent parallelism due to the algorithm decomposition and by utilizing the row-wise burst access pattern of the external memory. A high throughput memory interface has been designed to enable maximum utilization of the memory bandwidth. In addition, an automatic system generator is provided for mapping this architecture onto a reconfigurable platform of Xilinx Virtex5 devices. For a 2K x 2K input size, the proposed architecture is 1.96x times faster than RC decomposition based implementation under the same memory constraints, and also outperforms other existing implementations

Biosynthesized ZnO-NPs from Morus indica attenuates methylglyoxal-induced protein glycation and RBC damage: In-vitro, in-vivo and molecular docking study

The development of advanced glycation end-products (AGEs) inhibitors is considered to have therapeutic potential in diabetic complications inhibiting the loss of the biomolecular function. In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized from aqueous leaf extract of Morus indica and were characterized by various techniques such as ultraviolet (UV)-Vis spectroscopy, Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Further, the inhibition of AGEs formation after exposure to ZnO-NPs was investigated by in-vitro, in-vivo, and molecular docking studies. Biochemical and histopathological changes after exposure to ZnO-NPs were also studied in streptozotocin-induced diabetic rats. ZnO-NPs showed an absorption peak at 359 nm with a purity of 92.62% and ~6–12 nm in size, which is characteristic of nanoparticles. The images of SEM showed agglomeration of smaller ZnO-NPs and EDS authenticating that the synthesized nanoparticles were without impurities. The biosynthesized ZnO-NPs showed significant inhibition in the formation of AGEs. The particles were effective against methylglyoxal (MGO) mediated glycation of bovine serum albumin (BSA) by inhibiting the formation of AGEs, which was dose-dependent. Further, the presence of MGO resulted in complete damage of biconcave red blood corpuscles (RBCs) to an irregular shape, whereas the morphological changes were prevented when they were treated with ZnO-NPs leading to the prevention of complications caused due to glycation. The administration of ZnO-NPs (100 mg Kg−1) in streptozotocin(STZ)-induced diabetic rats reversed hyperglycemia and significantly improved hepatic enzymes level and renal functionality, also the histopathological studies revealed restoration of kidney and liver damage nearer to normal conditions. Molecular docking of BSA with ZnO-NPs confirms that masking of lysine and arginine residues is one of the possible mechanisms responsible for the potent antiglycation activity of ZnO-NPs. The findings strongly suggest scope for exploring the therapeutic potential of diabetes-related complications.Fil: Anandan, Satish. University of Mysore; IndiaFil: Mahadevamurthy, Murali. University of Mysore; IndiaFil: Ansari, Mohammad Azam. Imam Abdulrahman Bin Faisal University; Arabia SauditaFil: Alzohairy, Mohammad A.. Al Qassim University; Arabia SauditaFil: Alomary, Mohammad N.. King Abdulaziz City For Science And Technology; Arabia SauditaFil: Siraj, Syeda Farha. University of Mysore; IndiaFil: Nagaraja, Sarjan Halugudde. University of Mysore; IndiaFil: Chikkamadaiah, Mahendra. University of Mysore; IndiaFil: Ramachandrappa, Lakshmeesha Thimappa. University of Mysore; IndiaFil: Krishnappa, Hemanth Kumar Naguvanahalli. University of Mysore; IndiaFil: Ledesma, Ana Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Centro de Investigación en Biofísica Aplicada y Alimentos. - Universidad Nacional de Santiago del Estero. Centro de Investigación en Biofísica Aplicada y Alimentos; ArgentinaFil: Nagaraj, Amruthesh Kestur. University of Mysore; IndiaFil: Urooj, Asna. University of Mysore; Indi

Exploration of Anti-HIV Phytocompounds against SARS-CoV-2 Main Protease: Structure-Based Screening, Molecular Simulation, ADME Analysis and Conceptual DFT Studies

The ever-expanding pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has gained attention as COVID-19 and caused an emergency in public health to an unmatched level to date. However, the treatments used are the only options; currently, no effective and licensed medications are available to combat disease transmission, necessitating further research. In the present study, an in silico-based virtual screening of anti-HIV bioactive compounds from medicinal plants was carried out through molecular docking against the main protease (Mpro) (PDB: 6LU7) of SARS-CoV-2, which is a key enzyme responsible for virus replication. A total of 16 anti-HIV compounds were found to have a binding affinity greater than −8.9 kcal/mol out of 150 compounds screened. Pseudohypericin had a high affinity with the energy of −10.2 kcal/mol, demonstrating amino acid residual interactions with LEU141, GLU166, ARG188, and GLN192, followed by Hypericin (−10.1 kcal/mol). Moreover, the ADME (Absorption, Distribution, Metabolism and Excretion) analysis of Pseudohypericin and Hypericin recorded a low bioavailability (BA) score of 0.17 and violated Lipinski’s rule of drug-likeness. The docking and molecular simulations indicated that the quinone compound, Pseudohypericin, could be tested in vitro and in vivo as potent molecules against COVID-19 disease prior to clinical trials.This was also supported by the theoretical and computational studies conducted. The global and local descriptors, which are the underpinnings of Conceptual Density FunctionalTheory (CDFT) have beenpredicted through successful model chemistry, hoping that they could be of help in the comprehension of the chemical reactivity properties of the molecular systems considered in this study.Fil: Murali, Mahadevamurthy. University Of Mysore; IndiaFil: Gowtham, Hittanahallikoppal Gajendramurthy. Nrupathunga University; IndiaFil: Shilpa, Natarajamurthy. University Of Mysore; IndiaFil: Krishnappa, Hemanth Kumar Naguvanahalli. University Of Mysore; IndiaFil: Ledesma, Ana Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Centro de Investigación en Biofísica Aplicada y Alimentos. - Universidad Nacional de Santiago del Estero. Centro de Investigación en Biofísica Aplicada y Alimentos; ArgentinaFil: Jain, Anisha S.. University Of Mysore; IndiaFil: Shati, Ali A.. King Khalid University; Arabia SauditaFil: Alfaifi, Mohammad Y.. Vacsera Holding Company; EgiptoFil: Elbehairi, Serag Eldin I.. Jss Academy Of Higher Education And Research; IndiaFil: Achar, Raghu Ram. Pirogov Russian National Research Medical University; RusiaFil: Silina, Ekaterina. Universitat de Les Illesbalears; EspañaFil: Stupin, Victor. Centro de Investigaciónen Materiales Avanzados; MéxicoFil: Ortega Castro, Joaquín. Jss Academy Of Higher Education And Research; IndiaFil: Frau, Juan. Universitat de Les Illesbalears; EspañaFil: Flores Holguín, Norma. Centro de Investigaciónen Materiales Avanzados; MéxicoFil: Amruthesh, Kestur Nagaraj. University Of Mysore; IndiaFil: Shivamallu, Chandan. Jss Academy Of Higher Education And Research; IndiaFil: Kollur, Shiva Prasad. University Of Mysore; IndiaFil: Glossman Mitnik, Daniel. Centro de Investigaciónen Materiales Avanzados; Méxic

FPGA-based High-Performance Collision Detection: An Enabling Technique for Image-Guided Robotic Surgery

Collision detection, which refers to the computational problem of finding the relative placement or con-figuration of two or more objects, is an essential component of many applications in computer graphics and robotics. In image-guided robotic surgery, real-time collision detection is critical for preserving healthy anatomical structures during the surgical procedure. However, the computational complexity of the problem usually results in algorithms that operate at low speed. In this paper, we present a fast and accurate algorithm for collision detection between Oriented-Bounding-Boxes (OBBs) that is suitable for real-time implementation. Our proposed Sweep and Prune algorithm can perform a preliminary filtering to reduce the number of objects that need to be tested by the classical Separating Axis Test algorithm, while the OBB pairs of interest are preserved. These OBB pairs are re-checked by the Separating Axis Test algorithm to obtain accurate overlapping status between them. To accelerate the execution, our Sweep and Prune algorithm is tailor-made for the proposed method. Meanwhile, a high performance scalable hardware architecture is proposed by analyzing the intrinsic parallelism of our algorithm, and is implemented on FPGA platform. Results show that our hardware design on the FPGA platform can achieve around 8X higher running speed than the software design on a CPU platform. As a result, the proposed algorithm can achieve a collision frame rate of 1 KHz, and fulfill the requirement for the medical surgery scenario of Robot Assisted Laparoscopy.published_or_final_versio