Amit Singh

Bio: Amit Singh is an academic researcher from National Institute of Technology, Patna. The author has contributed to research in topics: Digital watermarking & Watermark. The author has an hindex of 57, co-authored 640 publications receiving 13795 citations. Previous affiliations of Amit Singh include Ithaca College & Center for Infectious Disease Research and Policy.

Development of Alternaria blight resistant lines through interspecific hybridization between Indian mustard (Brassica juncea L.) and white mustard (Brassica alba) through embryo rescue

Abstract: Wide hybridization is an important technique for incorporation of desirable characters among related species of plants. In the present study, interspecific hybridization was carried out through in vitro culture of ovules from the crosses between Brassica juncea (cv. RH30, RH8812, RH270 and RH345) and B. alba for purpose of transferring Alternaria blight resistance from B. alba to B. juncea. Ovules were excised from siliquae and cultured on seven different MS modified media. In all crosses, the hybrid siliquae were shorter in length than their parent plants due to interspecific hybridization barriers. Pod setting in hybrid plants ranged from 39 to 48% and number of ovules per pod were also very few. Best germination response was observed in ovules used from 20 DAP on basal medium supplemented with Kin (2.5 mg/l) and CH (0.5 g/l) (for cv. RH30 x B. alba) and MS + BAP (2.5 mg/l) + CH (0.5 mg/l) (for other crosses). Six rooting media were tried for root formation in regenerated shoots. Maximum rooting response was on MS medium supplemented with IAA (0.5 mg/l) in all hybrids. The regenerated hybrid plants were transferred to a mixture of sand: soil in 1:1 ratio in pots and about 70 percent hybrid plants for all the crosses were survived. Successful hybrid plants were grown in field upto F7 generations. Advanced generation progenies were also successfully confirmed using molecular marker analyses for Alternaria blight resistance character. In advanced generation, the hybrid plant’s characteristics were comparable to their Indian mustard parent plants and they were highly resistant to Alternaria blight disease.

Effect of Weed Management on Weed Interference, Nutrient Depletion by Weeds and Production Potential of Long Duration Pigeonpea (Cajanus cajan L.) under Irrigated Ecosystem

Abstract: Timely weed management is important to increase productivity in s longduration crop like pigeonpea. A field study to evaluate the effect of weed management on weed interference, nutrient depletion by weeds and production potential of long duration pigeonpea under irrigated ecosystem was conducted at Agricultural Research Farm, IAS, BHU, Varanasi during 2009-10 and 2010-11. Results revealed that use of imazethapyr @ 0.15 kg ha -1 followed by (fb) paraquat @ 0.4 kg ha -1 40 days after sowing (DAS) significantly (P ≤ 0.05) reduced the weed density, total weed density and total weed dry weight being statistically at par with two hand weeding (HWs) at 25 and 50 days after sowing (DAS). Weed control index, weed persistence index and weed index were the highest in weedfree, 2HWs and imazethapyr applied @ 0.15 kg ha -1 fb paraquat 0.4 kg ha -1 . However, weed-free treatment resulted in per cent higher yield attributes like pods plant -1 (32.0 and 29.5%), grains pod -1 (34 and 32.6%), 1000-grain weight (25.8 and 21.5%), grain yield (48.7 and 47.5%), gross returns (46.0 and 45.0%), net returns (54.6 and 53.0%) and benefit-cost ratio (40.7 and 38.5%), being significantly higher than weedy check but remained at par with 2-HWs, imazethapyr @ 0.15 kg ha -1 fb paraquat @ 0.4 kg ha -1 . The highest nutrient depletion by weeds was recorded in weedy check, whereas, the lowest was in imazethapyr @ 0.15 kg ha -1 fb paraquat 0.4 kg ha -1 . K e y w o r d s Hand weeding, Herbicides, Pigeonpea, Seed yield, Weed control index, Weed flora Accepted: 15 December 2019 Available Online: 20January 2020 Article Info Int.J.Curr.Microbiol.App.Sci (2020) 9(1): 676-689

An evaluation of potential intrinsically disordered and amyloidogenic regions in hemoglobins

Abstract: Discovery of intrinsically disordered proteins (IDPs) has challenged the traditional protein structure- function paradigm. IDPs lack stable tertiary and/or secondary structures and are highly abundant in proteome. Functional diversity of IDPs complements the functions of ordered proteins. Intriguingly, some IDPs share a propensity to form insoluble, ordered aggregates called amyloid and it has been proposed that potential amyloidogenic and disordered regions in polypeptide chains influence the conformation of proteins leading to the formation of such fibers and plaques which are hallmarks of neurodegenerative and many other protein conformational diseases. Recently, several studies have shown the ubiquitous presence of hemoglobin in life forms suggesting a wide variety of biological functions. However, there has been no report for intrinsically disordered hemoglobins or disordered regions in hemoglobins considering the burgeoning number of new hemoglobins, although myoglobin has been shown to have flexible regions. In silico tools were used to explore the possibility of presence of disordered regions in different hemoglobins from various organisms. Additionally, attempt was also made to identify amyloidogenic regions, if any, in hemoglobins. Such analysis revealed that several globins potentially display disorder in CD loop region, known to be critical for hemoglobin function and heme stability. In silico analysis also predicted the presence of putative amyloidogenic regions in newly discovered hemoglobins. These findings question the structural or functional relevance, demanding detailed investigation, of such disorders in hemoglobins, their implications in pathogenesis through amyloid formation and the role of heme binding in preventing formation of disordered regions or amyloids.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Pattern Recognition and Machine Learning

Abstract: Probability Distributions.- Linear Models for Regression.- Linear Models for Classification.- Neural Networks.- Kernel Methods.- Sparse Kernel Machines.- Graphical Models.- Mixture Models and EM.- Approximate Inference.- Sampling Methods.- Continuous Latent Variables.- Sequential Data.- Combining Models.

Harrison's Principles of Internal Medicine

Abstract: The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Shape‐Controlled Synthesis of Metal Nanocrystals: Simple Chemistry Meets Complex Physics?

Abstract: Nanocrystals are fundamental to modern science and technology. Mastery over the shape of a nanocrystal enables control of its properties and enhancement of its usefulness for a given application. Our aim is to present a comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals. We begin with a brief introduction to nucleation and growth within the context of metal nanocrystal synthesis, followed by a discussion of the possible shapes that a metal nanocrystal might take under different conditions. We then focus on a variety of experimental parameters that have been explored to manipulate the nucleation and growth of metal nanocrystals in solution-phase syntheses in an effort to generate specific shapes. We then elaborate on these approaches by selecting examples in which there is already reasonable understanding for the observed shape control or at least the protocols have proven to be reproducible and controllable. Finally, we highlight a number of applications that have been enabled and/or enhanced by the shape-controlled synthesis of metal nanocrystals. We conclude this article with personal perspectives on the directions toward which future research in this field might take.