BHU Institutional Repository :: Browsing by Author "Kumar, Amit"

Browsing by Author "Kumar, Amit"

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A 25/28 GHz Modified ?-shaped SIW-based Self-Diplexing Antenna with Low Frequency Ratio for 5G Applications
(Institute of Electrical and Electronics Engineers Inc., 2021) Kumar, Amit; Singh, Amit Kumar; Kumar, Munish
In this paper, a compact substrate integrated waveguide (SIW) based self-diplexing slot antenna for 25/28 GHz fifth generation (5G) applications is presented. The SIW cavity is loaded with a 7r-shaped asymmetric slot that produce two distinct frequency bands and hence, self-diplexing antenna (SDA) characteristics with low frequency-ratio. The placement of the slot is chosen in such a way that it helps in creating weak cross-coupling path between the excitation ports. The slight modification in the slots dimensions further improves the isolation (>30 dB) in both frequency bands. The simulated peak gain and radiation efficiency in both frequency bands are 8.64 dBi, 9.54 dBi and 98.18%, 96.73%, respectively. The front-to-back ratio (FTBR) of more than 22 dB in both frequency bands is achieved. � 2021 IEEE.
A 28/38 GHz Substrate Integrated Waveguide based Self-Diplexing Slot Antenna for 5G Applications
(Institute of Electrical and Electronics Engineers Inc., 2021) Kumar, Amit; Singh, Amit Kumar; Kumar, Munish
In this paper, a compact substrate integrated waveguide (SIW) based self-diplexing slot antenna for 28/38 GHz fifth generation (5G) applications is presented. The SIW cavity is loaded with three U-shaped slots that produce two distinct frequency bands and hence, self-diplexing antenna (SDA) characteristics. The placement of three different slots helps in creating weak cross-coupling path between the excitation ports. The slight modification in the slots dimensions further improves the isolation (>25 dB) in both frequency bands. The simulated peak gain and radiation efficiency in both frequency bands are 8.48 dBi, 7.64 dBi and 98.95%, 97.48%, respectively. The front-to-back ratio (FTBR) of more than 25 dB in both frequency bands is achieved. � 2021 IEEE.
A new approach for nano-structuring of glassy selenium (g-Se) using silver nanoparticles (AgNPs) as precursor
(Elsevier Ltd, 2021) Kumar, Amit; Mehta, N.; Dahshan, A.
Various routes have been proposed for the synthesis of chalcogen based nanostructured materials but the search of conventional and cost-effective method for the nanostructuring of chalcogenides is an ongoing research activity. This unique work reports the synthesis and the characterization of a novel kind of glassy nanocomposite material belonging to the nano-structuring of g-Se with the help of silver nanoparticles. The local structure is analyzed with the help of X-ray diffraction, Scanning electron microscopy, Raman spectroscopy, and Differential Scanning Calorimetry. It was found that the addition of AgNPs in glassy Se creates fine nano-wires of trigonal Selenium (t-Se) in the glass matrix of g-Se. The electrical, mechanical, and thermal characterizations of the present glassy nanocomposite material have been done in terms of current-voltage characteristics, d.c. conductivity, micro-hardness, and kinetic parameters of glass/crystal phase transformation. A comparative analysis of present glassy composites with a conventional Ag containing glassy alloy (g-Se98Ag2) has also been done to understand the role of incorporation of silver nanoparticles over the normal silver powder. The detailed analysis shows that different physical properties [e.g., thermal stability, modulus of elasticity, micro-hardness, the threshold voltage (i.e., turn-on voltage for resistive switching), and d.c. conductivity] are enhanced more effectively when the nano-structuring of g-Se by using AgNPs is executed as compared to the routine way of alloying. � 2020 Elsevier Ltd
Achyranthes aspera L. leaf extract induced anticancer effects on Dalton's Lymphoma via regulation of PKC? signaling pathway and mitochondrial apoptosis
(Elsevier Ireland Ltd, 2021) Singh, Rishi Kant; Verma, Praveen Kumar; Kumar, Amit; Kumar, Sandeep; Acharya, Arbind
Ethnopharmacological relevance: Epidemiological studies promote the inclusion of natural-products in diet due to their inhibitory effects on various types of cancer. Among them, Achyranthes aspera L. (Family Amaranthaceae) is a medicinal plant in Ayurvedic pharmacopeia, found in India, Southeast Asia, America, and Sub-Saharan Africa. It is endowed with anti-inflammatory, anti-oxidant, and anti-cancer activities. However, its potential effect on Non-Hodgkin lymphomas (NHLs), has not yet been clarified. Aim of the study: In the present study, we aimed to investigate the effect of Achyranthes aspera L. leaf extracts on highly aggressive murine NHL called Dalton's Lymphoma (DL) in vitro and in vivo. Material and methods: GC-HRMS analysis was carried out for the identification of compounds present in A. aspera leaf extract. The cytotoxicity of various A. aspera leaf extracts was evaluated on DL cells by MTT assay. Chromatin condensation, nuclear fragmentation, and morphological changes were observed by microscopy technique. Flow cytometry was used to measure the changes in mitochondrial membrane potential (??m) and apoptosis. In addition, the expressions of apoptosis-related proteins were detected by western blotting. Meanwhile, the in vivo anti-tumor effect of leaf extract was tested in DL induced Balb/c mice. Result: GC-HRMS analysis of A. aspera methanolic leaf extract (AAML) revealed the presence of ten pharmacologically active compounds. The results showed that AAML suppressed cell proliferation, decreased mitochondrial membrane potential, changed the morphological structure, and induced apoptosis. Moreover, AAML could promote the release of cytochrome c by regulating Bcl-2 family proteins and then activated caspase-9/ -3 to triggered cell apoptosis. At the same time in DL cells treated with AAML, the protein kinase C? (PKC?) pathway was inhibited in a concentration-dependent manner. Remarkably, in vivo, AAML mediated suppression of DL growth in Balb/c mice was accompanied by attenuation of the PKC? pathway and induction of apoptosis. Our result suggested that AAML promotes mitochondrial apoptotic cascade in DL cells by suppressing the PKC? signaling pathway. Conclusion: The study suggests that AAML could potently suppress DL progression by promoting apoptosis via mitochondrial-cascade and attenuation of the PKC? signaling pathway. � 2021
An insight into SARS-CoV-2 membrane protein interaction with spike, envelope, and nucleocapsid proteins
(Taylor and Francis Ltd., 2023) Kumar, Prateek; Kumar, Amit; Garg, Neha; Giri, Rajanish
Intraviral protein�protein interactions are crucial for replication, pathogenicity, and viral assembly. Among these, virus assembly is a critical step as it regulates the arrangements of viral structural proteins and helps in the encapsulation of genomic material. SARS-CoV-2 structural proteins play an essential role in the self-rearrangement, RNA encapsulation, and mature virus particle formation. In SARS-CoV, the membrane protein interacts with the envelope and spike protein in Endoplasmic Reticulum Golgi Intermediate Complex (ERGIC) to form an assembly in the lipid bilayer, followed by membrane-ribonucleoprotein (nucleocapsid) interaction. In this study, we tried to understand the interaction of membrane protein�s interaction with envelope, spike, and nucleocapsid proteins using protein�protein docking. Further, simulation studies were performed up to 100 ns to examine the stability of protein�protein complexes of Membrane-Envelope, Membrane-Spike, and Membrane-Nucleocapsid proteins. Prime MM-GBSA showed high binding energy calculations for the simulated structures than the docked complex. The interactions identified in our study will be of great importance, as it provides valuable insight into the protein�protein complex, which could be the potential drug targets for future studies. Communicated by Ramaswamy H. Sarma. � 2021 Informa UK Limited, trading as Taylor & Francis Group.
Application of Pteris vittata L. for phytoremediation of arsenic and biomonitoring of the process through cyto-genetic biomarkers of Trigonella foenum-graecum L.
(Springer, 2022) Gupta, Kiran; Srivastava, Sudhakar; Saxena, Gauri; Kumar, Amit
The arsenic (As) contamination demands its remediation from the environment which is naturally possible by the application of Pteris vittata L. However, biomonitoring of phytoremediation potential of P. vittata at chromosomal and DNA level is still meager. The present study was designed to biomonitor the phytoremediation efficiency of P. vittata through phytotoxic and cyto-genotoxic biomarkers assessment using Trigonella foenum-graecum L. (Fenugreek; Methi) as test system. Study revealed hyperaccumulation potential of P. vittata which extracted arsenic in its tissues. Biomonitoring evaluation depicted that phytotoxic damage was reduced in Trigonella exposed to remediated soil, which was revealed through reduced electrolyte leakage, hydrogen peroxide and MDA content. Moreover, cyto-genetic endpoints like mitotic depression (44.03%), relative abnormality rate (16.6%) and chromosomal abnormality frequency (1.06%) were also lesser in test plants grown in remediated soil compared to those grown in non-remediated soil. Along with this various chromosomal aberrations like stickiness, breaks, laggards, bridges, fragmentations and micronuclei were also augmented in test plants exposed to non-remediated arsenic enriched soil. It was evident that arsenic enriched soil caused toxicity to plants in dose-dependent manner that was assessable through the analysis of biochemical parameters and cyto-genetic biomarkers. The cyto-genetic biomarkers are very efficient, simple and non-expensive tools to biomonitor arsenic toxicity at chromosomal as well as DNA level to assess the remediation potential of P. vittata in field conditions. � 2022, Prof. H.S. Srivastava Foundation for Science and Society.
Bioefficacy, environmental safety and synergistic impacts of biorational formulations against whitefly, leafhopper and blister beetle in organic okra ecosystem
(Cambridge University Press, 2021) Singh, Satyapriya; Yadav, Gulab Singh; Das, Anup; Das, Biswajit; Devi, Hidangmayum Lembisana; Raghuraman, Mahadevan; Kumar, Amit
Whitefly (Bemisia tabaci Gennadius), leafhopper (Amrasca biguttula biguttula Ishida) and large yellow-banded blister beetle (Mylabris phalerata) cause considerable damage to okra, especially under organic farming. Thus, the present study was carried out to test the bioefficacy and environmental safety of six naturally derived components [indigenous water plant extracts, i.e. chilli (Capsicum annum), garlic (Allium sativum L.) and neem (Azadirachta indica A. Juss.) along with cow urine in three different combinations, one commercial botanical (azadirachtin 0.15%), and two formulated entomopathogenic fungi (Verticillium lecanii and Beauveria bassiana)] on aforesaid pests for two consecutive years at field scale. In addition to this, the eco-toxicological effect of naturally derived components was also studied on natural enemies' populations, viz. spiders and coccinellids. Quaternary mixture application of chilli, garlic, neem leaf and cow urine (CGNC) at 10% w/v was found effective in reducing leafhoppers (94.6%), whiteflies (95.2%) and blister beetle (94.6%) over control. Okra treated with CGNC produced a higher marketable fruit yield (18.44 mg/ha) than those of other treatments. It was also observed that the application of CGNC had no phytotoxic symptoms on okra plants. Application of CGNC was found safer to the natural enemy's population (spiders and coccinellids). Thus, the study suggests that CGNC can be considered as a potential source for managing the population of whitefly, leafhopper and blister beetle without affecting the ecology of natural enemies and it could be a viable eco-friendly option in organic okra production for ensuring food safety and healthy environment. Copyright � The Author(s), 2021. Published by Cambridge University Press.
Case Report: Nocardia amamiensis Infection Leading to Worsening of Chronic Obstructive Pulmonary Disease Symptoms in an Elderly Man
(American Society of Tropical Medicine and Hygiene, 2023) Kanakan, Ahalya; Kumar, Amit; Kaur, Upinder; Narwade, Prity; Rain, Zinnu; Yadav, Nidhi; Kumar, Ishan; Kumar, Deepak; Chakrabarti, Sankha Shubhra
Nocardiosis is a rare opportunistic infection mostly affecting the lungs, brain, or skin of immunocompromised individuals. Most pulmonary nocardiosis patients present with nonspecific clinical features such as productive cough, exertional dyspnea, and fever. The disease is uncommonly suspected, especially in tuberculosis-endemic regions, and clinical diagnosis is often delayed, resulting in high mortality. Pulmonary nocardiosis in apparently immunocompetent individuals is uncommon. Here, we present the case of an elderly gentleman with a background history of poorly controlled diabetes but no history of systemic steroid use who presented with worsening symptoms of chronic obstructive pulmonary disease in the form of productive cough and dyspnea. The patient had diffuse crepitations in bilateral lung fields and an arterial oxygen saturation of 86% at admission. Sputum microscopy revealed gram-positive filamentous bacteria that could be successfully cultured and identified as Nocardia amamiensis on 16S ribosomal RNA sequencing. Contrast-enhanced computed tomography of the lungs revealed cavitary nodules and consolidation. The patient responded well to treatment with specific antibiotics based on sensitivity patterns. Because of the nonspecific clinical and radiological findings in pulmonary nocardiosis, a high index of suspicion is required, especially in tuberculosis-endemic regions. � 2023 American Society of Tropical Medicine and Hygiene. All rights reserved.
Clinical profile of hospitalized COVID-19 patients in first & second wave of the pandemic: Insights from an Indian registry based observational study
(Wolters Kluwer Medknow Publications, 2021) Kumar, Gunjan; Mukherjee, Aparna; Sharma, Ravendra K.; Menon, Geetha R.; Sahu, Damodar; Wig, Naveet; Panda, Samiran; Rao, Vishnu Vardhan; Singh, Sujeet; Guleria, Randeep; Bhargava, Balram; Pakhare, Abhijit; Joshi, Rajnish; Bhuniya, Sourin; Panigrahi, Manoj Kumar; Bhardwaj, Pankaj; Misra, Sanjeev; Gupta, Manoj; Goel, Akhil D.; Mundadan, Netto George; Khan, Adil Rashid; Soneja, Manish; Baruah, Tridip Dutta; Kannauje, Pankaj Kumar; Kumar, Ajit; Yadhav, Kala M.L.; Kumar, Manoj; John, Mary; Mohan, Sangeetha; Patel, Amit; Madan, Surabhi; Mukherjee, Subhasis; Pal, Amitava; Banerjee, Saikat; Shah, Arti D.; Rana, Yash; Madharia, Arun; Madharia, Ankit; Bandaru, Rajiv Kumar; Mavoori, Archana; Dube, Simmi; Nahar, Nitin; Bingi, Thrilok Chander; Mesipogu, Rajarao; Aedula, Vinaya Sekhar; Panchal, Manisha; Mohammedrafiq, Mansuri Amirsohil; Upadhyay, Rashmi; Srivastava, Saurabh; Salgar, Veeresh B.; Desai, Rizwan; Kikon, Nyanthung; Kikon, Rhondemo; Sarangi, Lisa; Rath, Mahesh; Agarwal, Anup; Turuk, Alka; Sharma, Lokesh Kumar; Anand, Tanu; Bhatnagar, Tarun; Ghosh, Saumitra; Hazra, Avijit; Ray, Yogiraj; Ray, Rammohan; Patnaik, Lipilekha; Sahoo, Jagdish Prasad; Chakravarty, Jaya; Kansal, Sangeeta; Shameem, Mohammad; Fatima, Nazish; Kumar, M. Pavan; Rao, Bikshapathi; Himanshu, D.; Kumar, Amit; Dulhani, Naveen; Toppo, Amar Deepak; Sharma, Nikita; Vohra, Rajat; Kataria, Sushila; Sharma, Pooja; Talukdar, Arunansu; Dasgupta, Gargi; Desai, Anita; Nityasri, S.N.; Panchal, Yashmin; Manohar, K.; Raju, Y.S.; Pala, Star; Jamil, Md.; Katyal, V.K.; Goyal, Sandeep; Ojha, U.K.; Jha, Ravi Ranjan; Bhalla, Ashish; Puri, G.D.; Samita, S.; Suri, Vikas; Mohindra, Ritin; Pathak, Ashish; Sharma, Ashish; Khambholja, Janakkumar R.; Shah, Nehal M.; Palat, Paltial N.; Rajvansh, Kruti; Bhandari, Sudhir; Agrawal, Abhishek; Gupta, Bal Kishan; Gupta, Jigyasa; Choudhury, Ratnamala; Rao, Mangala; Chatterji, Soumyadip; Mukherjee, Sudipta
Background & objectives: India witnessed a massive second surge of COVID-19 cases since March 2021 after a period of decline from September 2020. Data collected under the National Clinical Registry for COVID-19 (NCRC) were analysed to describe the differences in demographic and clinical features of COVID-19 patients recruited during these two successive waves. Methods: The NCRC, launched in September 2020, is an ongoing multicentre observational initiative, which provided the platform for the current investigation. Demographic, clinical, treatment and outcome data of hospitalized, confirmed COVID-19 patients were captured in an electronic data portal from 41 hospitals across India. Patients enrolled during September 1, 2020 to January 31, 2021 and February 1 to May 11, 2021 constituted participants of the two successive waves, respectively. Results: As on May 11, 2021, 18961 individuals were recruited in the registry, 12059 and 6903 reflecting in-patients from the first and second waves, respectively. Mean age of the patients was significantly lower in the second wave [48.7 (18.1) yr vs. 50.7 (18.0) yr, P<0.001] with higher proportion of patients in the younger age group intervals of <20, and 20-39 yr. Approximately 70 per cent of the admitted patients were ? 40 yr of age in both waves of the pandemic. The proportion of males were slightly lower in second wave as compared to the first [4400 (63.7%) vs. 7886 (65.4%), P=0.02]. Commonest presenting symptom was fever in both waves. In the second wave, a significantly higher proportion [2625 (48.6%) vs. 4420 (42.8%), P<0.003] complained of shortness of breath, developed ARDS [422(13%) vs. 880 (7.9%), P<0.001], required supplemental oxygen [1637 (50.3%) vs. 4771 (42.7%), P<0.001], and mechanical ventilation [260 (15.9%) vs. 530 (11.1%), P<0.001]. Mortality also significantly increased in the second wave [OR: 1.35 (95% CI: 1.19, 1.52)] in all age groups except in <20 yr. Interpretation & conclusions: The second wave of COVID-19 in India was slightly different in presentation than the first wave, with a younger demography, lesser comorbidities, and presentation with breathlessness in greater frequency. � 2021 BioMed Central Ltd.. All rights reserved.
Conservation tillage and organic nutrients management improve soil properties, productivity, and economics of a maize-vegetable pea system in the Eastern Himalayas
(John Wiley and Sons Ltd, 2021) Singh, Raghavendra; Babu, Subhash; Avasthe, Ravi Kant; Meena, Ram Swaroop; Yadav, Gulab Singh; Das, Anup; Mohapatra, Kamal Prasad; Rathore, Sanjay Singh; Kumar, Amit; Singh, Chandu
Soil quality restoration and sustainable crop production in the rainfed ecosystem of the Indian Himalayas can be achieved through effective conservation tillage and organic management. Hence, a six-year (2013 to 2019) study was conducted to quantify the effect of tillage and organic nutrient management on soil properties, productivity, and profitability of the maize-vegetable pea (Pisum sativum) system. Three tillage practices [conventional (CT), reduced (RT), and no-till (NT)] and four organic nutrients management practices [(ONM)-farmyard manure @ 8�Mg ha?1 farmers practice (ONM1), 100% recommended dose of nitrogen (RDN) through manures (ONM2), 75% RDN through manures + maize/vegetable pea stover in either of the crops (ONM3), and 50% RDN through manures + maize/vegetable pea stover in either of the crops (ONM4)] were tested. The results indicated that the NT had higher soil organic carbon (SOC, 16.49 g kg?1), available N (354.5�kg ha?1), and lesser bulk density (1.31 Mg m?3) and penetration resistance (1.85 MPa) in comparison with that of CT at 0�10�cm depth. The system productivity under NT was 9.6% higher than that obtained under CT. The ONM3 had higher SOC content, plant-available N, soil microbial biomass carbon (SMBC), and dehydrogenase activity (DHA) than ONM1. The integration of RT-ONM2 enhanced SMBC, DHA, maize, and vegetable pea yield by 27.2%, 35.7%, 38.0%, and 60.3%, respectively, over CT-ONM1. Thus, the study suggested that the adoption of effective conservation tillage with adequate organic nutrient management has the potential to advance the soil properties and productivity of maize-vegetable pea system in the Himalayan Region. � 2021 John Wiley & Sons, Ltd.
Dry eye disease associated with Primary Sjogren syndrome: An update
(IP Innovative Publication Pvt. Ltd., 2021) Maurya, Rajendra P.; Singh, Vibha; Manisha; Gupta, Ashish; Singh, Virendra P.; Kumar, Amit; Yadav, Archana; Singh, Shivangi
Primary Sj�gren�s syndrome (pSS) is a chronic, multisystem autoimmune disorder, characterized by mononuclear infiltration of exocrine glands and other organs, resulting in dry eye, dry mouth and extra glandular systemic findings. Primary Sj�gren syndrome is of particular interest to ophthalmologists as it constitutes an important differential diagnosis in conditions with dry eye disease. The ocular tests are of great importance for diagnosis and monitoring of primary sjogren�s syndrome. Also a better understanding of immunological mechanisms and molecular pathways have resulted in discovery of new therapeutics for local and systemic treatment. This article illustrates an update regarding pathogenesis, diagnosis, investigative procedures and treatment options for dry eye related to Sjogren�s syndrome. � 2021 Innovative Publication, All rights reserved.
Earth Observation in Urban Monitoring: Techniques and Challenges
(Elsevier, 2023) Kumar, Amit; Srivastava, Prashant K.; Mall, Rajesh Kumar
Earth Observation in Urban Monitoring: Techniques and Challenges presents the latest techniques of remote sensing in urban monitoring, along with methods for quantitative and qualitative assessment using state-of-the-art Earth observation technologies. The book details the advances of remote sensing technologies in urban environmental monitoring for a range of practical and research applications, Earth observation datasets, remote sensing of environmental considerations, geostatistical techniques and resilience perspectives. Chapters cover sensor applications, urban growth modelling, SAR applications, surveying techniques, satellite time series analysis and a variety of other remote sensing technologies for urban monitoring. Each chapter includes detailed case studies at a variety of scales and from a variety of geographies, offering up-to-date, global, urban monitoring methodologies for researchers, scientists and academics in remote sensing, geospatial research, environmental science and sustainability. � 2024 Elsevier Ltd. All rights reserved.
Earth observations for urban policies and future pathways for urban environmental research
(Elsevier, 2023) Ekka, Pawan; Upreti, Manjari; Shilky; Saikia, Purabi; Kumar, Amit; Pandey, Prem C.; Srivastava, Prashant K.
Urban research is now evolving, and there are several challenges that need to be addressed in the near future, which has led to pathways for further development. The scientific community must consider a multitude of options for urban monitoring, evaluation, planning, and management. In this chapter, we have provided a brief overview of different models for urban studies and research based on Earth observation datasets. This chapter discusses a variety of potential research areas, including satellite-based monitoring of urban areas, IoT and cloud computing in urban management, and the use of machine learning in urban environmental research. In addition to digitization, the availability of big data sets, machine learning (ML), and artificial intelligence (AI) will revolutionize the way urban areas are analyzed and planned, opening up new possibilities for sustainable urban challenges. The chapter outlines qualitative and quantitative methods utilizing predictive models and scenario analysis for identifying and implementing urban environmental policies. The recommendations provided in this chapter can be used for further urban studies, research, and the development of smart and resilient cities. � 2024 Elsevier Ltd. All rights reserved.
Effect of Channel Designs and Its Optimization for Enhanced Thermo-Hydraulic Performance of Solar Air Heater
(American Society of Mechanical Engineers (ASME), 2022) Kumar, Amit; Singh, Ajeet Pratap; Akshayveer; Singh, O.P.
The increasing future energy demands can be met with solar-based devices such as solar air heaters (SAHs) only if the efficiency of these devices is enhanced with suitable design changes. Flow channel design of a SAH is an essential aspect for enhancing its thermohydraulic performance for a wide range of Reynolds numbers. In this article, a systematic approach has been adopted to investigate various nonrectangular channel designs numerically, and results are compared with the conventional rectangular design. The energy input to all designs is kept constant. The channel design that gives the best performance was further investigated by incorporating a sinusoidal wavy absorber having variable wavy roughness parameters. The flow and heat transfer characteristics have been evaluated in terms of friction factor (f) and Nusselt number per unit friction factor (Nu/f), temperature factor (To�Ti)/I, thermal effectiveness (?), and Nusselt number (Nu). The results show that the SAH duct having a semi-ellipse cross section offers the best thermohydraulic performance and has maximum augmentation in the temperature factor of about 10% compared to conventional SAH. Moreover, semi-ellipse SAH with sinusoidal wavy absorber has a maximum value of f/fs and Nu/Nus at A/Dh = 0.12 and ?/Dh = 0.8 for the range of Reynolds numbers used, respectively. Here, A is the amplitude and ? is the wavelength of the absorber plate. New empirical relationships for Nu and f are established as a function of flow and geometric parameters that agree well with numerical results. Copyright � 2022 by ASME.
Evaluating long-term variability in precipitation and temperature in eastern plateau region, India, and its impact on urban environment
(Springer Science and Business Media B.V., 2021) Kumar, Amit; Pandey, Arvind Chandra; Pandey, Swati; Srivastava, P.K.
In the present study, the long-term variability in precipitation and temperatures was analyzed in relation to the urban environment of Ranchi Metropolitan Region, eastern plateau region, India. The daily meteorological observations of 5�decades (1961�2010) indicated an increasing mean temperature (0.4��C) and decreasing cumulative precipitation in the Ranchi, capital region of the state Jharkhand. The results exhibited a declining precipitation patterns in the recent decade as compared to the earlier 4�decades. The high daily monsoon rainfall intensity with low cumulative precipitation can be observed during post-2000 periods, which indicate a highly erratic nature of precipitation in the region. Temporal census data demonstrated that the Ranchi urban region faced enormous proliferation in the human population (21 times) during the period 1927�2010 and thereby induced the extensive alteration in land use/land cover and rapid built-up expansion (> 5 times) as evidenced by the temporal satellite-based observations. The increasing annual per capita land consumption (361.50%) together with annual per capita loss of heat sink zones (96.3% during 1927�2010) and high influx of vehicles (563% during 1997�2010) influenced the local and regional climatic variable in the region. The results indicate that the rapid and haphazard urban sprawl in the last few decades and increase in built-up and impervious surface largely contributed in increasing the land surface temperature (34�42��C) as compared to the rural environment (30�38��C), which perhaps could be the region for the changes in climate and weather pattern of the area. � 2020, Springer Nature B.V.
Evaluation of canine bone marrow-derived mesenchymal stem cells for experimental full-thickness cutaneous wounds in a diabetic rat model
(Taylor and Francis Ltd., 2021) Bist, Deepika; Pawde, A.M.; Amarpal; Kinjavdekar, Prakash; Mukherjee, Reena; Singh, K.P.; Verma, Med Ram; Sharun, Khan; Kumar, Amit; Dubey, Pawan K.; Mohan, Divya; Verma, Amit; Sharma, G. Taru
Background: The wound healing potential of canine bone marrow-derived mesenchymal stem cells (BMSCs) was evaluated in the excisional wound of streptozotocin-induced diabetic rats. Research design and methods: Xenogenic BMSCs were collected aseptically from the iliac crest of healthy canine donors under general anesthesia. Full-thickness experimental wounds (20 � 20 mm2) on the dorsum of forty-eight adult healthy Wistar white rats. The wounds were assigned randomly to three treatment groups: PBS (Group A) or BMSCs (Group B) injected into the wound margins on days 0, 7, and 14 or BMSCs (Group C) injected into the wound margins on days 7, 14, and 21 post-wounding. The degree of wound healing was evaluated based on macroscopical, hemato-biochemical, histopathological, and histochemical parameters. Results: The results indicated granulation tissue formation with reduced exudation and peripheral swelling in the treatment groups compared to the control group A. Similarly, the degree of wound contraction was significantly higher in groups B and C animals than group A on days 14 and 21 post-wounding. The transplantation of BMSCs resulted in early drying of wounds, granulation tissue appearance, and enhanced cosmetic appearance. Conclusion: The histopathological, histochemical, and gross findings suggested the therapeutic potential of xenogeneic mesenchymal stem cell therapy in managing diabetic wounds. Abbreviations: BMSCs-bone marrow-derived mesenchymal stem cells, PBS-phosphate-buffered saline, MSCs-mesenchymal stem cells, FBS-fetal bovine serum, ECM-extracellular matrix. � 2021 Informa UK Limited, trading as Taylor & Francis Group.
Evaluation of Phytoremediation Potential of Pteris vittata L. on Arsenic Contaminated Soil Using Allium cepa�Bioassay
(Springer, 2022) Gupta, Kiran; Srivastava, Sudhakar; Saxena, Gauri; Kumar, Amit
The present study assessed the utility of Allium cepa based cyto-genotoxicity bioassays in evaluating the arsenic toxicity and remediation potential of Pteris vittata on contaminated soil of Lakhimpur-Kheri district. Untreated and P. vittata treated soil extracts were used for cyto-genotoxicity tests in A. cepa. Results showed that P. vittata extracted high concentration of arsenic, which ranged from 220 to 1420 mgkg?1 in different soils. Cyto-genotoxic assessment of A. cepa showed that extract of P. vittata treated soil had lower cyto-genotoxic effects as compared to untreated soil. A higher mitotic index (10%) while lower mitotic depression (29%), relative abnormality rate (10%), chromosomal aberrations (1%) and micronuclei (2%) were detected in root meristematic cells of A. cepa exposed to remediated soil extract in comparison to untreated soil. The studies provide a simple, rapid and economic cyto-genotoxicity bioassay tool for evaluating toxicity of contaminated soils of contaminated soils as well as revealed the phytoremdiation property of P. vittata against arsenic toxicity. � 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Evidence-Based Therapeutic Potential of Natural Seed Oil of Desert Date/Ingudi (Balanites aegyptiaca Linn. Delile) in Chronic Diabetic Wound
(Springer, 2023) Kumar, Sanjeev; Mishra, Anurag; Dwivedi, Kamal Nayan; Singh, Neelu; Kumar, Abhishek; Bhartiya, Satyanam Kumar; Krishnamoorthi, S.; Kumar, Amit; Goel, Bharat; Jain, Shreyans K.
This study is to clarify the things said in Ayurveda and Sanskrit literature with evidence in today's context that Balanites aegyptiaca oil (BAO) was used on humans and animals to heal wounds without any side effects. BAO was tested for its wound-healing potential on a diabetic patient. The topical application of the BAO caused wound closure that was ascertained by histopathological changes that occurred during the treatment at the site of application. The phytochemical analysis of BAO resulted in the isolation of potential marker compounds such as diosgenin, caffeic acid, stigmasterol, and fatty acids that may be contributing factors to its wound healing potential. However, underlying mechanisms need to be explored to understand the mechanism behind their wound-healing property. � 2023, The Author(s), under exclusive licence to The National Academy of Sciences, India.
Generative Adversarial Neural Machine Translation for Phonetic Languages via Reinforcement Learning
(Institute of Electrical and Electronics Engineers Inc., 2023) Kumar, Amit; Pratap, Ajay; Singh, Anil Kumar
Neural Machine Translation (NMT) heavily depends on the context vectors generated via attention network for the target word prediction. Existing works primarily focus on generating context vectors from words or subwords of sentences, limiting NMT models' ability to learn sufficient information about the source sentence representations. These situations are even worse when languages belong to extremely low-resource categories due to rare word problem. To improve the learning of source sentence representations and handle the rare word problem of Low Resource Languages (LRLs), we propose a novel improvement in Generative Adversarial Networks (GAN)-NMT by incorporating deep reinforcement learning-based optimised attention in generator and convolutional neural network in discriminator. We also create the novel joint embedding of subwords and sub-phonetic representation of sentences as input to GAN that helps models to learn the better representations and generate suitable context vectors compared to existing traditional approaches for LRLs. To show the effectiveness of our method, we demonstrate experiments on LRLs pairs, e.g., Gujarati Hindi, Nepali Hindi, Punjabi Hindi, Maithili Hindi and Urdu Hindi. Our proposed novel approach suppress the existing state-of-the-art techniques with considerable improvement. � 2017 IEEE.
Geospatial technology in agroforestry: status, prospects, and constraints
(Springer, 2023) Sharma, Prashant; Bhardwaj, Daulat Ram; Singh, Manoj Kumar; Nigam, Rahul; Pala, Nazir A.; Kumar, Amit; Verma, Kamlesh; Kumar, Dhirender; Thakur, Pankaj
Agroforestry has an indispensable role in food and livelihood security in addition to its capacity to combat the detrimental effects of climate change. However, agroforestry has not been properly promoted and exploited due to lack of precise extent, geographical distribution, and carbon sequestration (CS) assessment. The recent advent of geospatial technologies, as well as free availability of spatial data and software, can provide new insights into agroforestry resources assessment, decision-making, and policy development despite agroforestry�s small spatial extent, isolated nature, and higher structural and functional complexity of agroforestry. In this review, the existing application of geospatial technologies together with its constraints and limitations as well as the potential future application for agroforestry has been discussed. The review reveals that the application of optical remote sensing in agroforestry includes spatial extent mapping, production of tree species spectral signature, CS assessment, and suitability mapping. Simultaneously, the recent surge in the use of synthetic aperture radar in conjunction with algorithms based on vegetation photosynthesis and optical data enables a more accurate estimation of gross primary productivity at different scales. However, unmanned aerial vehicles equipped with sensors, such as multispectral, LiDAR, hyperspectral, and thermal, offer a considerably higher potential and accuracy than satellite-based datasets. In the future, the health monitoring of agroforestry systems can be a key concern that may be addressed by utilizing hyperspectral and thermal datasets to analyze plant biochemistry, chlorophyll fluorescence, and water stress. Additionally, current (GEDI, ECOSTRESS) and future space agency missions (BIOMASS, FLEX, NISAR, TRISHNA) have enormous potential to shed fresh light on agroforestry systems. � 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

Browsing by Author "Kumar, Amit"

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