Palladium(II)-catalyzed oxidation of tranexamic acid by bromamine-B in alkaline medium and uncatalyzed reaction in acid medium: A study of kinetic and mechanistic chemistry

Tranexamic acid (TA) possess antifibrinolytic properties and finds extensive applications in pharmaceuticals. Its oxidation-kinetic study is of much significance in understanding the mechanistic profile of TA in biological systems. In this context, a systematic kinetic study of palladium(II) (Pd(II)) catalyzed oxidation of TA by sodium N-bromobenzenesulfonamide or bromamine-B (BAB) in alkaline medium and uncatalyzed reaction in perchloric acid medium at 303 K was investigated. In acid medium, the reaction exhibits a first-order dependence of rate on BABo and less than unity order dependence on TAo. The reaction rate shows inverse less than unity order dependence with respect to H+. In alkaline medium, the reaction shows first-order dependence on both BABo and Pd(II) and zero-order with respect to TAo. The order with respect to OH - is less than unity. Activation parameters have been evaluated. The oxidation reactions are nearly 10-fold faster in acid medium in comparison with alkaline medium. In alkaline medium, the Pd(II) catalyzed reactions are about 6-fold faster than the uncatalyzed reaction. Further, the catalytic constant (KC) has been calculated at different temperatures and activation parameters with respect to Pd(II) catalyst have also been evaluated. The conjugate acid C6H5SO2NHBr and the anion C 6H5SO2N-Br of BAB have been postulated as the reactive oxidizing species in acid and alkaline media, respectively. The proposed mechanisms and derived rate laws are in agreement with the observed kinetics. © 2010 Elsevier B.V. All rights reserved

Analysis of optimized multilevel matrix converter for DFIG based wind energy conversion system

Wind power generation is an increasing trend worldwide. Multilevel converters in this regard are playing an essential role in high power system applications due to various features. In this paper, multi-objective optimization based multilevel matrix converter (MOMMC) is proposed for wind energy conversion system. The assessment of feasibility through the discussion of two objectives: reliability and cost have been considered in this study. Initially, the model of the two objectives is assessed against redundancy configuration and power loss. Then a multi-objective function is defined for achieving low cost and high reliability. The optimal topology for the matrix multi-level converter is determined using the membership function, and the solution is selected from the Pareto-optimal set. The reliability and cost analysis of the proposed MOMMC is performed. Simulation is carried out for the proposed multi-objective optimization based multilevel matrix converter using the PSIM software. To establish the validity of the proposed method, two different cases: 1) fixed and 2) variable speed of 9 MW doubly-fed induction generator-based wind energy system are considered. The results show the superiority of the proposed method over the others.

Evaluation of Matured Larval Weight and Larval Duration of New Breeding Lines of Bombyx mori L

We planned to conduct this study with the main aim to develop bivoltine breeds for our tropical climatic conditions by using silkworm breeds with known genetic backgrounds (KA, NB18 and PM) in various hybrid combinations and incorporating them over generations, followed by backcrossing and adequate selection of different generations with the objective of profitability and productivity. The isolated Bivoltin lines (R1 and R2) were reared with their parental races at different times of the year to evaluate their stability in the expression of commercial traits. For the present breeding program, the purebred Bivoltine Kalimpong-A (KA), which spin white oval cocoons, New Bivoltine18 (NB18) white cocoons with rotating dumbbells and Multivoltine Pure Mysore (PM), the yellow pointed cocoons of the mulberry silkworm Bombyx mori L., Selected. One-way and three-way crosses were made using the above three breeds. The first single cross comprised KA females and PM males. The second unique cross comprised NB18 females and PM males. Selection was performed at the egg, larva, pupal, and cocoon stages over the course to determine the desired traits. The offspring of F from the respective crosses were backcrossed with their respective bivoltine males to improve commercial traits. Heterosis in the F1 generations of crosses, including NB18 and PM, was determined by the mean score of the parents (MPV) and the best score of the parents (BPV). A significant test for heterosis was performed using a standard ANOVA table. Based on the results of our study, it was found that the performance of the characters, viz. The weight of mature larvae and the duration of the larvae over generations do not simply increase or decrease regularly, but fluctuate irregularly. The reason for this variation may be due to random genetic drift, sampling errors in estimating generational means, selection pressures, and environmental factors. Therefore, inbreeding variations due to random drift and sampling errors could be reduced by increasing the number sampled and selected. View Article DOI: 10.47856/ijaast.2021.v08i10.00

Requirement of p21-activated Kinase (PAK) for Salmonella typhimurium–induced Nuclear Responses

Salmonella typhimurium has sustained a long-standing association with its host and therefore has evolved sophisticated strategies to multiply and survive within this environment. Central to Salmonella pathogenesis is the function of a dedicated type III secretion system that delivers bacterial effector proteins into the host cell cytoplasm. These effectors stimulate nuclear responses and actin cytoskeleton reorganization leading to the production of proinflammatory cytokines and bacterial internalization. The stimulation of these responses requires the function of Cdc42, a member of the Rho family of small molecular weight GTPases, and SopE, a bacterial effector protein that stimulates guanine nucleotide exchange on Rho GTPases. However, nothing is known about the role of Cdc42 effector proteins in S. typhimurium–induced responses. We showed here that S. typhimurium infection of cultured epithelial cells results in the activation of p21-activated kinase (PAK), a serine/threonine kinase that is an effector of Cdc42-dependent responses. Transient expression of a kinase-defective PAK blocked both S. typhimurium– and SopE-induced c-Jun NH2-terminal kinase (JNK) activation but did not interfere with bacteria-induced actin cytoskeleton rearrangements. Similarly, expression of SH3-binding mutants of PAK did not block actin-mediated S. typhimurium entry into cultured cells. However, expression of an effector loop mutant of Cdc42Hs (Cdc42HsC40) unable to bind PAK and other CRIB (for Cdc42/Rac interacting binding)-containing target proteins resulted in abrogation of both S. typhimurium–induced nuclear and cytoskeletal responses. These results show that PAK kinase activity is required for bacteria-induced nuclear responses but it is not required for cytoskeletal rearrangements, indicating that S. typhimurium stimulates cellular responses through different Cdc42 downstream effector activities. In addition, these results demonstrate that the effector loop of Cdc42 implicated in the binding of PAK and other CRIB-containing target proteins is required for both responses

Contrasting Infection Strategies in Generalist and Specialist Wasp Parasitoids of Drosophila melanogaster

Although host–parasitoid interactions are becoming well characterized at the organismal and cellular levels, much remains to be understood of the molecular bases for the host immune response and the parasitoids' ability to defeat this immune response. Leptopilina boulardi and L. heterotoma, two closely related, highly infectious natural parasitoids of Drosophila melanogaster, appear to use very different infection strategies at the cellular level. Here, we further characterize cellular level differences in the infection characteristics of these two wasp species using newly derived, virulent inbred strains, and then use whole genome microarrays to compare the transcriptional response of Drosophila to each. While flies attacked by the melanogaster group specialist L. boulardi (strain Lb17) up-regulate numerous genes encoding proteolytic enzymes, components of the Toll and JAK/STAT pathways, and the melanization cascade as part of a combined cellular and humoral innate immune response, flies attacked by the generalist L. heterotoma (strain Lh14) do not appear to initiate an immune transcriptional response at the time points post-infection we assayed, perhaps due to the rapid venom-mediated lysis of host hemocytes (blood cells). Thus, the specialist parasitoid appears to invoke a full-blown immune response in the host, but suppresses and/or evades downstream components of this response. Given that activation of the host immune response likely depletes the energetic resources of the host, the specialist's infection strategy seems relatively disadvantageous. However, we uncover the mechanism for one potentially important fitness tradeoff of the generalist's highly immune suppressive infection strategy

HEMICHOREA: AN UNUSUAL MANIFESTATION OF THYROTOXICOSIS

ABSTRACTChorea is usually associated with neurological diseases. However, it can also be seen in patients with systemic lupus erythematosus (SLE), rheumaticfever (Sydenham's chorea), polycythemia vera, and thyrotoxicosis. Here, we report an interesting case of hemichorea in a 32-year-old lady, whopresented with acute onset of jerky, non-repetitive involuntary movements of the left upper and lower limbs. After detailed evaluation, she was foundto have thyrotoxicosis. Thyroid Tc-scan showed diffuse uptake suggesting Grave's disease. A magnetic resonance imaging of the brain was normal.Other causes of chorea like SLE and rheumatic fever were excluded. She was started on carbimazole. On follow-up after 6 weeks of therapy, there wasthe complete disappearance of chorea, and her thyroid hormone levels were normal.Keywords: Extrapyramidal syndrome, Hyperthyroidism, Corpus striatum, Dancing movements

Assessing performance of horticultural farmers producer companies: Comparative case study

Every year the horticultural sector of India faces huge quantity of food wastage due to lack of processing, value addition and post-harvest handling. Farmers Producer Company (FPC) can mitigate the loss through ensuring better value chain management. There are several horticulture based FPCs established in different parts of India. They have grown very fast and competing with agro-industries. The present study aimed to assess the performance of FPCs working in horticulture sector. The study was conducted in Maharashtra State of India by selecting three FPCs working in horticultural sector. Performance of these FPCs was assessed through Effectiveness Index developed for this study. Seven components viz. functional effectiveness, increase in income, increase in farmers share in consumers rupees, inclusiveness, sustainability of company, farmers satisfaction and empowerment were included in the index by following standard index forming protocol. Sahyadri Farms was found the best performing one among the selected FPCs, regarding effectiveness with a mean index score of 63.69 followed by Vasundhara Agro Producer Company Limited (50.20) and Junnar Taluka FPC Ltd. (41.29)