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13. List of contributors

Author

Abro, Naveed Qasim, primary, Achiou, Brahim, additional, Adhikari, Priyanka, additional, Alami Younssi, Saad, additional, Ali, Banafsheh Haji, additional, Ali, Zafar, additional, Baghdadi, Majid, additional, Bajpayee, Anand Kumar, additional, Balouch, Aamna, additional, Baran, Chhavi, additional, Bayuseno, A.P., additional, Bhardwaj, Abhishek Kumar, additional, Bhardwaj, Laxmi Kant, additional, Bharti, Abhi Sarika, additional, Bhuyan, Rajashree, additional, Bordoloi, Palakshi, additional, Breida, Majda, additional, Bui, Minh Quy, additional, Chafiq Elidrissi, Zakariya, additional, Chandola, Dinesh, additional, Chang, Zhen Hong, additional, Chauhan, Shikha Baghel, additional, Choudhury, Kristi Priya, additional, Darbha, Gopala Krishna, additional, Das, Parna, additional, Das, Ranjita S., additional, Debnath, Shrestha, additional, Devika, Y., additional, Dhyani, Vibhash, additional, Dikshit, Anupam, additional, El Machtani Idrissi, Doha, additional, Essate, Ahlam, additional, Gaur, Manish, additional, Geed, Sachin Rameshrao, additional, Ghosal, Partha Sarathi, additional, Ghosh, Dipankar, additional, Gunarto, Chintya, additional, Gupta, Ena, additional, Ismail, R., additional, Jagirani, Muhammad Saqaf, additional, Jamari, J., additional, Jha, Saket, additional, Jindal, Tanu, additional, Kakakhel, Mian Adnan, additional, Kalhoro, Muhammad Siddique, additional, Kataria, Navish, additional, Katyal, Deeksha, additional, Khandelwal, Nitin, additional, Khuhawar, Aftab Hussain, additional, Kori, Abdul Hameed, additional, Kouzi, Youness, additional, Kumar, Anupama, additional, Kumar, Naresh, additional, Laghari, Sakib Hussain, additional, Lyly, Leow Hui Ting, additional, Mahesar, Sarfaraz Ahmed, additional, Majumder, Abhradeep, additional, Malik, Aastha, additional, Mandal, Pubali, additional, Memon, Najma, additional, Misra, Charu, additional, Muryanto, S., additional, Narwal, Nishita, additional, Neogi, Newton, additional, Noor, Uroosa, additional, Ojha, Rudra Prakash, additional, Ouammou, Mohamed, additional, Pandey, Rahul, additional, Pathak, Ashok Kumar, additional, Purwar, Shalini, additional, Puspitasari, Nathania, additional, Rakib, Md. Refan Jahan, additional, Retnoningtyas, Ery Susiany, additional, Samal, Kulbhushan, additional, Sarkar, Soumita, additional, Saxena, Shikha, additional, Selvaraj, Devi, additional, Sherazi, Syed Tufail Hussain, additional, Shukla, Mohee, additional, Shukla, Rohit, additional, Singh, Abhimanyu Kumar, additional, Singh, Ravikant, additional, Soetaredjo, Felycia Edi, additional, Soni, Shashi, additional, Subhan, Md Abdus, additional, Teow, Yeit Haan, additional, Thathola, Pooja, additional, Tiwari, Ajay Kumar, additional, Tokas, Rajat, additional, Toppo, Swati Rose, additional, Tripathi, Shipra, additional, Truong, Thi Thao, additional, Uttam, Kailash Narayan, additional, Vairaperumal, Tharmaraj, additional, Verma, Jitendra Singh, additional, Verma, Manisha G., additional, and Yadav, Manoj Kumar, additional

Published
2024
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14. Parameter Distributions for the Drag-Based Modeling of CME Propagation

Author

Napoletano, Gianluca, Foldes, Raffaello, Camporeale, Enrico, de Gasperis, Giancarlo, Giovannelli, Luca, Paouris, Evangelos, Pietropaolo, Ermanno, Teunissen, Jannis, Tiwari, Ajay Kumar, and Del Moro, Dario

Subjects
Physics - Space Physics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics, Physics - Geophysics
Abstract

In recent years, ensemble modeling has been widely employed in space weather to estimate uncertainties in forecasts. We here focus on the ensemble modeling of CME arrival times and arrival velocities using a drag-based model, which is well-suited for this purpose due to its simplicity and low computational cost. Although ensemble techniques have previously been applied to the drag-based model, it is still not clear how to best determine distributions for its input parameters, namely the drag parameter and the solar wind speed. The aim of this work is to evaluate statistical distributions for these model parameters starting from a list of past CME-ICME events. We employ LASCO coronagraph observations to measure initial CME position and speed, and in situ data to associate them with an arrival date and arrival speed. For each event we ran a statistical procedure to invert the model equations, producing parameters distributions as output. Our results indicate that the distributions employed in previous works were appropriately selected, even though they were based on restricted samples and heuristic considerations. On the other hand, possible refinements to the current method are also identified, such as the dependence of the drag parameter distribution on the CME being accelerated or decelerated by the solar wind, which deserve further investigation., Comment: 25 pages, 9 figures, accepted for publication by Space Weather Journal. The ICME catalog built for the analysis in Section 3, together with a tool for the data visualization and the module employed for running the PDBM simulations, can be downloaded from https://doi.org/10.5281/zenodo.5818470 (Napoletano et al., 2021)

Published
2022
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17. Propagating kink waves in the solar corona

Author

Tiwari, Ajay Kumar, Mclaughlin, James, and Morton, Richard

Subjects
523.7, F300 Physics, F500 Astronomy
Abstract

The solar atmosphere is known to host various modes of MHD waves. Transverse waves are thought to play an important role in energy transfer in the atmosphere and thus in solar coronal heating and the acceleration of the solar wind. The transverse waves studied so far have predominantly been interpreted as standing kink waves and, via coronal magneto-seismology, they can offer insight into the physical conditions of coronal plasmas. In addition, the excitation of these standing kink waves are associated with low coronal eruptions and thus need special conditions or drivers. Propagating kink waves have been reported recently and have been found to be ubiquitous in the solar corona including in the quiet Sun. It is imperative to understand the mechanisms that enable their energy to be transferred to the plasma. Carrying on the legacy of the standing kink waves, mode conversion via resonant absorption is thought to be one of the main mechanisms for damping of these propagating kink waves, and is considered to play a key role in the process of energy transfer. The propagating kink waves are best observed in the Doppler velocity images of the Coronal Multi-channel Polarimeter (CoMP). The damping is observed using data from this instrument to study the energetics of the propagating kink waves in quiescent coronal loops. A coherence-based method is used to track the Doppler velocity signal of the waves, enabling an investigation into the spatial evolution of velocity perturbations. To enable accurate estimates of these quantities, the first derivation is provided of a likelihood function suitable for fitting models to the ratio of two power spectra obtained from discrete Fourier transforms. Maximum likelihood estimation is used to fit an exponential damping model to the observed variation in power ratio as a function of frequency. This also confirms earlier indications that propagating kink waves are undergoing frequency-dependent damping. Additionally, it is found that the rate of damping decreases, or equivalently the damping length increases, for longer coronal loops that reach higher in the corona. The analysis techniques are used to create a statistical sample of quiescent loops to study the statistical properties of propagating kink waves and compare it to the studies of standing kink waves. It is noted that the damping for the propagating waves appears to be significantly weaker than that found from measurements of standing kink modes. The propagating kink waves also exhibit signatures of power amplification of waves.

Published
2020

19. Overview of phytoplasma diseases in Asian countries

Author

Tiwari, Ajay Kumar, primary, Gazel, Mona, additional, Yadav, Amit, additional, Al-Sadi, Abdullah M., additional, Abeysinghe, Saman, additional, Nejat, Naghmeh, additional, Oshima, Kenro, additional, Bertaccini, Assunta, additional, and Rao, Govind P., additional

Published
2023
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21. List of contributors

Author

Abeysinghe, Saman, primary, Al-Sadi, Abdullah Mohammed, additional, Bagheri, Abdolnabi, additional, Bao Chau, Nguyen Ngoc, additional, Caglayan, Kadriye, additional, Celia Chalam, V., additional, Choueiri, Elia, additional, Deepika, D.D., additional, Endo, Ai, additional, Faghihi, Mohammad Mehdi, additional, Hemmati, Chamran, additional, Huang, Ching-Ting, additional, Kalaiponmani, K., additional, Kumari, Sapna, additional, Kumari, Pooja, additional, Kuo, Chih-Horng, additional, Lakhanpaul, Suman, additional, Maurya, A.K., additional, Nikooei, Mehrnoosh, additional, Oshima, Kenro, additional, Pei, Shen-Chian, additional, Quoc, Nguyen Bao, additional, Rao, Govind Pratap, additional, Salehi, Mohammad, additional, Siampour, Majid, additional, Singh, Amrita, additional, Tiwari, Ajay Kumar, additional, Tulum, Isil, additional, Ustun, Nursen, additional, Widana Gamage, S.M.K., additional, Yadav, Priya, additional, and Zamharir, Maryam Ghayeb, additional

Published
2023
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26. Biotic Stresses in Sugarcane Plants and Its Management

Author

Nikpay, Amin, Tiwari, Ajay Kumar, Vejar-Cota, Guadulope, Ziaee, Masumeh, Wilson, Blake, Srivastava, Sweta, Goebel, Francois-Regis, Verma, Krishan K., editor, Song, Xiu-Peng, editor, Rajput, Vishnu D., editor, Solomon, Sushil, editor, Li, Yang-Rui, editor, and Rao, Govind P., editor

Published
2022
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33. Perceived Life Outcomes of Indian Children During the Early Phase of the COVID-19 Lockdown: The Protective Roles of Joint and Nuclear Families.

Author

Tiwari, Gyanesh Kumar, Tiwari, Raghavendra Prasad, Pandey, Rakesh, Ray, Bablu, Dwivedi, Abhigyan, Sharma, Devaki Nandan, Singh, Pankaj, Tiwari, Ajay Kumar, and Singh, Ajit Kumar

Subjects
NUCLEAR families, COVID-19 pandemic, STAY-at-home orders, COVID-19, FOOD habits, HEALTH behavior
Abstract

Background: Although many negative consequences of the COVID-19 pandemic are reported for adults, little is known about its impacts on children, especially in terms of the relative roles of joint and nuclear families. Using a qualitative design, we explored the protective roles of joint and nuclear families in shaping the children’s life outcomes during COVID-19. Methods:In a qualitative study, 16 full-time mothers of children aged 9-12 years (8 each from joint and nuclear families) from Sagar City, India were interviewed during June and July 2020. Interview contents were audiotaped, transcribed verbatim, and analyzed using the thematic analysis method. Results: Five major themes were identified, negative impacts of the COVID-19 pandemic, differences in positive engagements, emotional protective benefits, promotion of positive health habits, and routine activity management strategies. The results showed that the joint families availed and utilized more resources to positively engage their children in creativity, studies, exercise, and entertainment during the restrictions of the lockdown compared to the nuclear families. Contrary to the nuclear families, the joint families emphasized resolving emotional grievances, promoting positive emotional engagement, and extending more emotional support to their children. The joint and nuclear families also differed in their children’s food habits, health grievances, and physical exercise. Also, the joint families played more positive roles in managing children’s play behaviors, sleep habits, television watching, and other children’s activities compared to the nuclear families. Conclusion: The distinctive availability of experiential, emotional, relational, and positive value resources and knowledge repertoires of the two family systems may have extended differential protective benefits to their children during the COVID-19 lockdown. [ABSTRACT FROM AUTHOR]

Published
2024
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34. Variability of phytoplasma associated with weeds grown in and around sugarcane crop in Uttar Pradesh, India.

Author

Mishra, Nistha, Dwivedi, Surya Prakash, Singh, Jitender, Tiwari, Ajay Kumar, and Marcone, Carmine

Abstract

During survey from 2013 to 2018, Cynodon dactylon at Shahjahnapur, Azamagarh, Oplismenus burmannii at Shahjahnapur, Arundo donax at Deoria and Ocimum cannum at Gorakhpur were observed with phytoplasma suspected symptoms. The maximum disease incidence (34%) was recorded at Deoria District in case of A. donax plant with witches' broom symptom. The nested PCR using universal primer pairs (R16F2n/R16R2) confirmed the phytoplasma association with all the suspected samples. Further BLASTn and phylogenetic analysis of the sequences revealed the association of 16SrXIV-A subgroups phytoplasma with C. dactylon , O. burmannii and phytoplasma belonging to 16SrI-B subgroups with A. donax and O. cannum plants in the present study. [ABSTRACT FROM AUTHOR]

Published
2023
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38. Parameter Distributions for the Drag‐Based Modeling of CME Propagation

Author

Napoletano, Gianluca, primary, Foldes, Raffaello, additional, Camporeale, Enrico, additional, de Gasperis, Giancarlo, additional, Giovannelli, Luca, additional, Paouris, Evangelos, additional, Pietropaolo, Ermanno, additional, Teunissen, Jannis, additional, Tiwari, Ajay Kumar, additional, and Del Moro, Dario, additional

Published
2022
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42. Innovative investigation of zinc oxide nanoparticles used in dentistry

Author

Tiwari, Ajay Kumar, Jha, Saket, Singh, Abhimanyu Kumar, Mishra, Sheo Kumar, Pathak, Ashok Kumar, Ojha, Rudra Prakash, Yadav, Raghvendra Singh, Dikshit, Anupam, Tiwari, Ajay Kumar, Jha, Saket, Singh, Abhimanyu Kumar, Mishra, Sheo Kumar, Pathak, Ashok Kumar, Ojha, Rudra Prakash, Yadav, Raghvendra Singh, and Dikshit, Anupam

Abstract

Dental caries is a major lifestyle concern as dental components affect the face of an individual. The issue of tooth decay occurs in every age group throughout the globe. Researchers are probing incipient implements and techniques to develop filling agents for decayed teeth. Zinc oxide (ZnO) powder is utilized mostly as a filling agent. Nanotechnology enhanced the efficiency of compounds of metal oxides utilized for dental caries. The present study aims to investigate the properties of ZnO nanoparticles (NPs) synthesized chemically (using ZnCl2 and NaOH) as well as biologically (using aqueous leaf extract of Murraya paniculata). The XRD patterns confirm that ZnO NPs have a hexagonal crystalline structure with particle sizes of 47 nm and 55 nm for chemically and biologically synthesized NPs, respectively. The FE-SEM data confirm the nanorod and spherical/cubical shape morphologies for the chemically and biologically synthesized ZnO NPs, respectively. FTIR data show the peaks between 4000 and 450 cm(-1) of the functional groups of -OH, C-O, -C-H-, and Zn-O bonds. The UV-Vis absorption study indicates a peak around 370 nm and a hump around 360 nm corresponding to the chemically and biologically synthesized ZnO NPs, respectively. An antibacterial bioassay was performed and compared with commercially available ZnO bulk powder against tooth decaying pathogens, viz., Streptococcus mutans, Staphylococcus aureus, E. coli, and Lactobacillus fermentum, and found that both ZnO NPs had results closer to those of the standard drug (rifampicin). Thus, the synthesized ZnO NPs may be utilized as nano-drugs for the application of tooth decaying filling agents. Even biologically synthesized ZnO NPs may be considered more environmentally friendly and less toxic to human health concerns.

Published
2022

46. SEARCH: SEgmentation of polAR Coronal Holes

Author

Tiwari, Ajay Kumar, Benoit Tremblay, Andong Hu, Wolniewicz, Linnea M., Kirk, Michael, Guidoni, Silvina, Smith, Brent, Penn, Matthew, and Tanmoy Samanta

Subjects
Active Regions, Machine Learning, Physics::Space Physics, Sun, Synchronic Maps, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Coronal Holes
Abstract

The identification of solar coronal holes (CHs) observed in Extreme Ultraviolet (EUV) intensity images of the Sun is key in improving our understanding of their association with solar magnetic fields and heliophysics. In particular, CHs at the poles of the Sun are a notorious source of fast solar wind and thus warrant further study, most notably in the context of space-weather forecasting. This has consequently led to the development of various segmentation methods for their identification, including supervised machine learning. We introduce the SEARCH project to combine EUV data from the three vantage points (e.g., STEREO-A, STEREO-B, and SoHO) during the 2010-2014 epoch to produce synchronic maps and apply unsupervised learning methods including clustering and convolutional neural networks for the segmentation of CHs. SEARCH segmentation maps provide a venue to explore the relationship between CH pole areas, geomagnetic activity, and the magnetic activity cycle (dynamo process) of the Sun and Sun-like stars. Finally, in addition to CHs, the unsupervised learning methods we tested identified features consistent with active regions., Join us over Zoom to discuss the poster: Time: Mar 3, 2021 10:00-11:00 AM Eastern Time (US and Canada) https://cuboulder.zoom.us/j/94533917426 Meeting ID: 945 3391 7426 Time: Mar 4, 2021 11:00-12:00 AM Eastern Time (US and Canada) https://cuboulder.zoom.us/j/97212897487 Meeting ID: 972 1289 7487, {"references":["SEARCH: SEgmentation of polaR Coronal Holes, NeurIPS 2020: Third Workshop on Machine Learning and the Physical Sciences"]}

Published
2021
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