404 results on '"Krishna, Prasad"'
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2. Biosorption of Cu+ 2 by Green Algae, Ulva fasciata: Optimization by Response Surface Methodology.
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Kadimpati, Kishore Kumar, Sanneboina, Sujatha, Thadikamala, Sathish, and Mondithoka, Krishna Prasad
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- 2024
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3. Scope and Mechanism of the Ruthenium-Catalyzed sp3C–H Coupling Reaction of 2-Alkylindoles with Enones for the Synthesis of Carbazole Derivatives
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Gnyawali, Krishna Prasad, Son, Mina, Hwang, Donghun, Pannilawithana, Nuwan, Baik, Mu-Hyun, and Yi, Chae S.
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The catalytic system consisting of a cationic Ru–H complex 1and 3,4,5,6-tetrachloro-1,2-benzoquinone (L1) was found to be highly effective for the dehydrative sp3C–H coupling reaction of 2-alkyl substituted indoles with enones to form 2,4-disubstituted carbazole products. The analogous coupling reaction of 2-alkylindoles with linear enones bearing the cyclic olefinic group afforded tetracyclic carbazole products. A normal deuterium kinetic isotope effect was measured from the coupling reaction of 1,2-dimethylindole versus 1-methyl-2-(methyl-d3)indole with (E)-3-penten-2-one (kH/kD= 2.5). The Hammett plot was constructed from the reaction of para-substituted indoles 5-X-1,2-dimethylindole (X = OMe, Me, H, F, and Cl) with 4-phenyl-3-buten-2-one (ρ = −1.6 ± 0.2). The density functional theory (DFT) calculations were performed to obtain a complete energy profile for the coupling reaction. The combined experimental and DFT computational data revealed a detailed mechanistic path that features an initial coupling of indole and enone substrates, the turnover-limiting heterolytic sp3C–H activation step, and the subsequent cyclization and dehydration steps. The catalytic method provides an efficient synthesis of carbazole derivatives from the dehydrative sp3C–H coupling reaction of readily available indole with enone substrates without employing any reactive reagents or forming wasteful byproducts.
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- 2025
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4. Influence of an Imposed Network on One- and Three-Dimensional Photonic Liquid Crystal Structures through the Polymer Template Technique
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Sahoo, Rajalaxmi, Pisharody, Gayathri R., Shankar Rao, D. S., Yelamaggad, C. V., and Krishna Prasad, S.
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We describe the first investigations on the influence of an imposed network on the photonic band gap (PBG) structure of the liquid crystal (LC) phase through the polymer template technique. The technique consists of using a cholesteric (Ch) phase as a base for photopolymerizing a difunctional monomer, which is then removed after polymerization, leaving only the polymer scaffold template. The templated structure obtained is utilized to adjust the PBG structure of the filled LC material, exhibiting both a one-dimensional PBG (Ch phase) and a three-dimensional PBG structure (TGBC* phase with smectic C* blocks). Selective reflection measurements indicate that the imprint polymer network of the template impacts the pitch of the Ch and TGBC* phases. The absorption peaks are visible because of two distinct twisted arrangements, one originating from the template and the other from the refilled chiral substance. In the templated cell, the central wavelength (λmin) of PBG of the refilled sample red-shifts, as well as the width of the PBG gets enhanced compared to that for the sample in the regular (nontemplated) cell. For example, in the TGBC* phase, the λminvalue red-shifts by 369 nm, and the width of the PBG enlarges by 50%. Additionally, the lattice spacing arising due to the periodicity of the SmC* helix in 2-dimension in the TGBC* phase gets enhanced. These findings demonstrate the polymer template method’s effectiveness in tuning the mesophase’s PBG in all three dimensions.
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- 2024
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5. Altemeier Procedure for Complete Rectal Prolapse: An Operation for all Ages and its Long-Term Functional Outcomes
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Murugesan, Thamarai Kannan, Srinivasan, Karthikeyan, Pillai, Sastha Ahanatha, Ramasamy, Villalan, Mikkilineni Bharani, Krishna Prasad Chowdary, Sreepathi, Venkkatesh, and Subbareddiar, Padmanabhan
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- 2024
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6. Enhanced Prediction of Swimmer Fitness Using Modified Resilient PSO Algorithm
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Geetha Poornima, K. and Krishna Prasad, K.
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Sports develop both physical and mental growth of an individual. In order to enhance the physical and mental health effectively and effortlessly, swimming is considered to be one of the healthier activities, in developing the metabolism via flexibility, weight loss, reducing asthma and enhancing the fitness levels of the body. In most of the cases, existing studies provide the current status of the swimmer by delivering details like time taken by the swimmers to finish the lap or location of the swimmer, however they lack in identifying the calorie level reduction of the swimmer during the swimming, as, the detection of calories burnt by the swimmer helps in overcoming issues like loss of weight and other health risk rates. Therefore, proposed study intensifies in achieving the prediction of the fitness of a swimmer as the primitive activity in view of reducing the calories by using PSO algorithm using resilient based techniques for enhanced exploration ability and using modified resilient PSO in order to tune the hyper parameter of the random forest for better optimization outcome. Modified resilient PSO helps in preventing the over-fitting of the model and delivering enhanced global solutions. Besides, hyper parameter are tuned in the Random Forest (RF), Decision Tree (DT), AdaBoost and Support Vector Machine (SVM) regression model for an error free outcome and with satisfactory performance analytical values. Finally, the performance of the proposed model is assessed using performance metrics such as R-square, RMSE, MSE and MAE, unveiling the effectiveness of the projected approach MPSO-XG-Boost. The projected model has achieved effectual outcomes encompassing less error rate based outcomes in ranges of 0.037, 0.191, 0.059, 0.9. Further, the proposed is compared with the existing models in order to determine the efficiency of the proposed framework.
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- 2024
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7. Layer Resolved Cr Oxidation State Modulation in Epitaxial SrFe0.67Cr0.33O3−δ Thin Films.
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Koirala, Krishna Prasad, Hossain, Mohammad Delower, Wang, Le, Zhuo, Zengqing, Yang, Wanli, Bowden, Mark E., Spurgeon, Steven R., Wang, Chongmin, Sushko, Peter V., and Du, Yingge
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- 2024
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8. Exploring the Effects of Online Learning Complications on Mathematics Achievement.
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Joshi, Dirgha Raj, Khadka, Jiban, Adhikari, Krishna Prasad, Khanal, Bishnu, and Belbase, Shashidhar
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ONLINE education ,DIGITAL technology ,DIGITAL literacy ,MATHEMATICS students ,ACADEMIC achievement - Abstract
The aim of the research was to examine different complications of learning mathematics online and their effects on students' academic performances. A crosssectional survey design was employed among 2311 students from the school to university levels in Nepal. Hierarchical linear regression and machine learning were major statistical techniques used in the research. The findings indicated that access to and cost of digital devices, training on digital skills, assignment submission skills, digital literacy, and a separate study room at home were major complications for students in learning mathematics online. Additionally, these complications to learning mathematics online negatively affect students' academic performance. This research gives new insights into the complications of online learning and its effect on learners' performance in mathematics as well. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Structural Evolution in Disordered Rock Salt Cathodes.
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Li, Tianyu, Geraci, Tullio S., Koirala, Krishna Prasad, Zohar, Arava, Bassey, Euan N., Chater, Philip A., Wang, Chongmin, Navrotsky, Alexandra, and Clément, Raphaële J.
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- 2024
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10. Female and underrepresented minority representation in radiology.
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Doddi, Sishir, Khalafi, Mona, Shimoura, Elizabeth, Shanbhogue, Krishna Prasad, and Tirumani, Sree Harsha
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Diversity, equity, inclusion, and representation in various sectors have garnered increasing attention in the past two decades, including healthcare. In this report we investigate representation of females and underrepresented minorities (URM) in the field of radiology and asses for significant growth trends in representation in residency training programs in the United States. De-identified trainee demographic information for active radiology trainees from 2016 to 2021 was queried using the Accreditation Council for Graduate Medical Education (ACGME), and new radiology trainees using the National Resident Matching Program (NRMP)'s Main Residency Match Data and Reports databooks. In 2021 females represented 26.7% of DR residency trainees and 22% of IR integrated trainees. In the same year URM trainees represented 11.3% of trainees and 8.7% of IR integrated trainees. From 2017 to 2021, diagnostic radiology had a compound average growth rate (CAGR) 1% (p <0.01) of female representation and 1.12% (p<0.01) of URM representation. This study quantifies female and underrepresented minority representation among radiology trainees for diagnostic radiology and radiology subspecialities, identifying modest uptrends in representation within both demographics. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Layer Resolved Cr Oxidation State Modulation in Epitaxial SrFe0.67Cr0.33O3−δThin Films
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Koirala, Krishna Prasad, Hossain, Mohammad Delower, Wang, Le, Zhuo, Zengqing, Yang, Wanli, Bowden, Mark E., Spurgeon, Steven R., Wang, Chongmin, Sushko, Peter V., and Du, Yingge
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Understanding how doping influences physicochemical properties of ABO3perovskite oxides is critical for tailoring their functionalities. In this study, SrFe0.67Cr0.33O3−δepitaxial thin films were used to examine the effects of Fe and Cr competition on structure and B-site cation oxidation states. The films exhibit a perovskite-like structure near the film/substrate interface, while a brownmillerite-like structure with horizontal oxygen vacancy channels predominates near the surface. Electron energy loss spectroscopy shows Fe remains Fe3+, while Cr varies from ∼Cr3+(tetrahedral layers) to ∼Cr4+(octahedral layers) within brownmillerite phases and becomes ∼Cr4.5+in perovskite-like phases. Theoretical simulations indicate that Cr–O bond arrangements and the way oxygen vacancies interact with Cr and Fe drive Cr charge disproportionation. High-valent Cr cations introduce additional densities of states near the Fermi level, reducing the optical bandgap from ∼2.0 eV (SrFeO2.5) to ∼1.7 eV (SrFe0.67Cr0.33O3−δ). These findings offer insights into B-site cation doping in the perovskite oxide framework.
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- 2024
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12. Structural Evolution in Disordered Rock Salt Cathodes
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Li, Tianyu, Geraci, Tullio S., Koirala, Krishna Prasad, Zohar, Arava, Bassey, Euan N., Chater, Philip A., Wang, Chongmin, Navrotsky, Alexandra, and Clément, Raphaële J.
- Abstract
Li-excess Mn-based disordered rock salt oxides (DRX) are promising Li-ion cathode materials owing to their cost-effectiveness and high theoretical capacities. It has recently been shown that Mn-rich DRX Li1+xMnyM1–x–yO2(y≥ 0.5, M are hypervalent ions such as Ti4+and Nb5+) exhibit a gradual capacity increase during the first few charge–discharge cycles, which coincides with the emergence of spinel-like domains within the long-range DRX structure coined as “δ phase”. Here, we systematically study the structural evolution upon heating of Mn-based DRX at different levels of delithiation to gain insight into the structural rearrangements occurring during battery cycling and the mechanism behind δ phase formation. We find in all cases that the original DRX structure relaxes to a δ phase, which in turn leads to capacity enhancement. Synchrotron X-ray and neutron diffraction were employed to examine the structure of the δ phase, revealing that selective migration of Li and Mn/Ti cations to different crystallographic sites within the DRX structure leads to the observed structural rearrangements. Additionally, we show that both Mn-rich (y≥ 0.5) and Mn-poor (y< 0.5) DRX can thermally relax into a δ phase after delithiation, but the relaxation processes in these distinct compositions lead to different domain structures. Thermochemical studies and in situ heating XRD experiments further indicate that the structural relaxation has a larger thermodynamic driving force and a lower activation energy for Mn-rich DRX, as compared to Mn-poor systems, which underpins why this structural evolution is only observed for Mn-rich systems during battery cycling.
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- 2024
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13. Twist Angle-Dependent Phonon Hybridization in WSe2/WSe2Homobilayer
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Bera, Krishna Prasad, Solanki, Darshit, Mandal, Shinjan, Biswas, Rabindra, Taniguchi, Takashi, Watanabe, Kenji, Raghunathan, Varun, Jain, Manish, Sood, A. K., and Das, Anindya
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The emerging moiré superstructure of twisted transition metal dichalcogenides (TMDs) leads to various correlated electronic and optical properties compared to those of twisted bilayer graphene. In such a versatile architecture, phonons can also be renormalized and evolve due to atomic reconstruction, which, in turn, depends on the twist angle. However, observing this reconstruction and its relationship to phonon behavior with conventional, cost-effective imaging methods remains challenging. Here, we used noninvasive Raman spectroscopy on twisted WSe2/WSe2(t-WSe2) homobilayers to examine the evolution of phonon modes due to interlayer coupling and atomic reconstruction. Unlike in the natural bilayer (NB), ∼0° as well as ∼60° t-WSe2samples, the nearly degenerate A1g/E2gmode in the twisted samples (1–7°) split into a doublet in addition to the nondegenerate B2gmode, and the maximum splitting is observed around 2–3°. Our detailed theoretical calculations qualitatively capture the splitting and its dependence as a function of the twist angle and highlight the role of the moiré potential in phonon hybridization. Additionally, we found that around the 2° twist angle, the anharmonic phonon–phonon interaction is higher than the natural bilayer and decreases for larger twist angles. Interestingly, we observed anomalous Raman frequency softening and line-width increase with the decreasing temperature below 50 K, pointing to the combined effect of enhanced electron–phonon coupling and cubic anharmonic interactions in moiré superlattice.
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- 2024
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14. Benzoquinone Ligand-Enabled Ruthenium-Catalyzed Deaminative Coupling of 2‑Aminoaryl Aldehydes and Ketones with Branched Amines for Regioselective Synthesis of Quinoline Derivatives.
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Gnyawali, Krishna Prasad, Shakenov, Aldiyar, Kirinde Arachchige, Pandula T., and Yi, Chae S.
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- 2024
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15. Classification of Tooth Anomalies - Endodontist's Perspective.
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Agarwal, Sanjana, Shetty, Krishna Prasad, Rai, Namith, and Ballal, Nidambur Vasudev
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MOLARS ,DENTAL pulp cavities ,PEER communication ,TREATMENT effectiveness ,TEETH - Abstract
Root canal anomalies can be challenging to treat. Classification systems provide a framework which helps the clinician in effective diagnosis and treatment planning, improves treatment precision, analyses the risk assessment and treatment outcome, helps in education and communication with peers and has research implications. With advancements in technology, the understanding of the complex anatomy of the root canal system is improving drastically. This review caters from the old to the most recent classification. The anomalies included are Palatogingival Groove, Dens Invaginatus, Dens Evaginatus, Talon's Cusp, C-Shaped Canals, Taurodontism, Root Fusions, Radix Entomolaris and Paramolaris, Maxillary molar and Maxillary premolar with extra root. This review highlights various classification systems for tooth anomalies which impact the endodontic treatment strategy. It provides a holistic perspective to the clinician such that management of such anomalies can be done effectively. [ABSTRACT FROM AUTHOR]
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- 2024
16. Molybdenum induced defective WO3 multifunctional nanostructure as an electrochromic energy storage device: Novel assembled photovoltaic-electrochromic Mo–WO3 film.
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Krishna Prasad, Aryal, Kim, Jae-Young, Kang, Soon-Hyung, and Ahn, Kwang-Soon
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ENERGY storage ,MOLYBDENUM ,ELECTROCHROMIC devices ,OPEN-circuit voltage ,ELECTROSTATIC discharges ,POTENTIAL energy ,TUNGSTEN oxides - Abstract
[Display omitted] • Mo-doped WO 3 as a multifunctional nanostructure. • Oxygen defect sites are successfully grown over WO 3 surface. • Doped nanostructure provides sufficient active sites for insertion and extraction of Li
+ ions. • Novel assembly of QDSSC assisted electrochromic integrated device is developed. In this work, a self-powered electrochromic device incorporating molybdenum-doped tungsten oxide (WO 3) is developed for enhanced performances, offering a potential solution for energy efficient technologies. Defective nanostructure of WO 3 , enabled with molybdenum doping, is achieved through an electrochemical co-deposition method. A film of Mo–WO 3 is investigated for multifunctional purposes, acting as both an electrochromic (EC) and energy storage device (ESD). As an EC film, it exhibits an optimal optical contrast of 84.5 %, minimum coloration time of 0.4 s, high coloration efficiency of 90.4 cm2 /C, and excellent optical stability. In ESD applications, Mo–WO 3 displays charge-transfer resistance of 7.6 Ω, a commendable capacitance of 39.1 mF/cm2 , and excellent capacitance retention of 80.4 %. The integration of Mo ions into the WO 3 nanostructure results in the formation of oxygen defect sites, which enhances the mobility of Li+ ions over the amorphous and deagglomerated morphology of Mo–WO 3. Furthermore, the EC activity of Mo–WO 3 film does not require an external power source as the film is powered by an integrated quantum dot-sensitized solar cell (QDSSCs). The open circuit voltage of 0.62 V, resulting from the QDSSCs power source, successfully facilitates the switching operation of the Mo–WO 3 EC film. [ABSTRACT FROM AUTHOR]- Published
- 2024
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17. EFFECT OF PREFERENCE AND MANAGEMENT OF E-ASSESSMENT SYSTEM ON ITS QUALITY ASSURANCE PROCESS.
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Adhikari, Krishna Prasad, Joshi, Dirgha Raj, Khadka, Jiban, and Khanal, Bishnu
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PSYCHOLOGY of students ,QUALITY assurance ,STRUCTURAL equation modeling - Abstract
This study aims to explore university students’ perception regarding an e-assessment system in terms of preference, assessment management, and the quality assurance process. A cross-sectional online survey was employed among 384 students of Nepal Open University (NOU). Structural equation modeling (SEM) was used in the research. Findings indicate that the perception of students regarding preference, e-assessment management, and the quality assurance process was found to be significantly high. In particular, the perception of preference regarding digital assessment was higher than assessment management and the quality assurance process. Gender, ethnicity, and place for taking classes, have an effect on implementation. This study concludes that three attributions of preference for digital assessment, management, and quality assurance are affected by one another. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Three-Dimensional Polymeric-Scaffold-Based Current Collector for a Lithium Metal Anode toward High-Energy-Density Batteries.
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Kim, Ju-Myung, Jia, Hao, Koirala, Krishna Prasad, Liu, Dianying, Simmons, Ashley, Engelhard, Mark H., Ahmed, Ridwan A., Zhang, Yuepeng, Wang, Chongmin, Zhang, Ji-Guang, and Xu, Wu
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- 2024
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19. Direct Mapping of Fluorine in Cation Disordered Rocksalt Cathodes.
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Koirala, Krishna Prasad, Jiang, Lin, Patil, Shripad, Longo, Paolo, Liu, Zhao, Freitag, Bert, Barthel, Juri, Self, Ethan C., Du, Yingge, Pullan, Lee, Tessner, Ted, Allen, Leslie J., Xu, Wu, Tong, Wei, Nanda, Jagjit, and Wang, Chongmin
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- 2024
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20. Learners' Expectations towards Virtual Learning and its Effect on Mathematics Performance.
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Joshi, Dirgha Raj, Khadka, Jiban, Khanal, Bishnu, and Adhikari, Krishna Prasad
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COVID-19 pandemic ,EXPECTATION (Psychology) ,LEARNING ,MATHEMATICS ,DATA analysis - Abstract
The demands for virtual learning have exponentially increased because of the COVID-19 pandemic. The aim of the research was to explore learners' expectations towards virtual learning and its effect on mathematics achievement. A total of 2,350 students from basic to university levels in Nepal participated in the cross-sectional survey. T-test, ANOVA, and SEM were employed for data analysis. The findings indicate that the expectation of learners towards virtual learning from the government, educational institutions, teachers, and parents found to be significantly high. Parents' level of education, gender, and the types of educational institutions are key predictors of the expectation of learners. Expectations of learners towards virtual learning from government, institutions, and parents have negative and expectations from teachers have a positive effect on mathematics performance. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Epidemiological, Serological, and Entomological Investigation of New Visceral Leishmaniasis Foci in Nepal.
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Joshi, Anand Ballabh, Banjara, Megha Raj, Das, Murari Lal, Ghale, Pragyan, Pant, Krishna Raj, Pyakurel, Uttam Raj, Dahal, Gokarna, Paudel, Krishna Prasad, Das, Chuman Lal, Kroeger, Axel, and Aseffa, Abraham
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- 2024
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22. Conformational Properties of Aβ Peptide Oligomers in Aqueous Ionic Liquid Solution: Insights from Molecular Simulation Studies.
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Sahoo, Subhadip, Pal, Tamisra, Mondal, Souvik, Ghanta, Krishna Prasad, and Bandyopadhyay, Sanjoy
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- 2023
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23. A STUDY OF VARIOUS BARRIERS IN IMPLEMENTING "ENHANCED RECOVERY AFTER CARDIAC SURGERY (ERACS)" PROGRAM IN INDIAN SETUP.
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Kalla, Krishna Prasad G, V K, ARYA, Puri, Goverdhan Dutt, Thingnum, Shyam Singh, Singh, Harkant, and Ganesan, Rajarajan
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Introduction – Complications associated with major surgeries can be prevented or reduced by changing conventional practices and by implementing evidence-based protocols such as enhanced recovery after cardiac surgery (ERACS) protocols in patient care. However, the adherence rate to the newly developed protocols is low in developing countries like India due to the presence of various barriers to implementation. Knowledge of these barriers is important to overcome them and to implement the ERACS program with full adherence. There is a paucity of literature about these barriers in Indian cardiac surgical centers. Hence, we have designed this prospective observational study to evaluate the various barriers while implementing the ERACS program. The primary objective is to evaluate the compliance rate for ERACS protocol and to identify various barriers involved in its non-compliance. The secondary objective is to compare the mechanical ventilation duration and length of hospital stay in the compliant and non-compliant groups. METHODS - 19 protocols were included in the ERACS program and proposed for implementation in a > 18-year-old patients undergoing cardiac surgery between July 2017 to Dec 2022. Implementation of these protocols was silently observed by a person not related to the study. For non-compliance observations, the concerned team members were interviewed by the same observer to spell out reasons without any acquisitions at the end of the day. RESULTS - 577 patients were enrolled in the study where the ERACS protocol was supposed to be implemented. A total of 7464 point observations were made out of which the non-compliance rate for the ERACS program was 2100 (28.2%). The percentage of non-compliance in decreasing order was ultrasound-guided central line insertion(70%), pre-briefing (62%), and insertion of atrial pacing wire (57%). The percentage of compliance in decreasing order was preoperative checklist filling (100%) antibiotic administration before 30 minutes of surgical incision (97%), timely postoperative feeding (89%), timely extubation (87%), performing proper weekly audit (84%), attaching defibrillator pads (75%), optimizing co-morbidities (74%), giving 2nd dose of antibiotic (74%). Reasons for non-compliance were classified into 9 barriers. The most common barrier was mental inertia (33.9%) to change practices followed by lack of motivation (13.7%). In 12% of ERACS protocol was not followed due to poor knowledge and training. The mean length of ICU stay was significantly less for patients where pre-briefing and proper handover were done (4.9±1.33 vs 5.5±1.73; p < 0.001). The mean duration of mechanical ventilation was significantly low in patients in whom handover was given properly (9.4±5.72 vs 14.1±8.63; p = 0.002). - This is the 1st qualitative study that has been done to evaluate various barriers in the Indian cardiac surgical setup for the implementation of ERACS protocol. The compliance and non-compliance rate of the ERACS program was 71.8% and 28.2% respectively. We observed 9 barriers to non-compliance for implementing the ERACS program. Mental inertia (33.9%) towards practice change is the most common barrier found in our study followed by a lack of motivation in staff members (13.7%). [ABSTRACT FROM AUTHOR]
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- 2024
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24. LOW DOSE VASOPRESSIN INFUSION POST-CARDIOPULMONARY BYPASS IN PATIENTS WITH LEFT VENTRICULAR DYSFUNCTION: A RANDOMIZED CONTROLLED TRIAL.
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Ganesan, Rajarajan, Chakraborty, Kajori, Biswas, Indranil, Negi, Sunder, Mishra, Anand, Agarwal, Pankaj, and Gourav, Krishna Prasad
- Abstract
The usefulness of low-dose infusion of vasopressin in patients having left ventricle(LV) dysfunction undergoing cardiac surgery with cardiopulmonary bypass(CPB) is not well studied. Our study aimed to evaluate the hemodynamic and clinical effects of low-dose vasopressin infusion in this patient population. Our primary hypothesis is that vasopressin infusion reduces the cardiac index measured at the end of CPB. This randomised double-blinded controlled trial was conducted in 36 patients of age above 18 years, planned for elective cardiac surgery with CPB and presenting with LV dysfunction preoperatively. Patients in the vasopressin group (n=18) received 1.2 units per hour of vasopressin infusion started at the end of CPB while patients in the control group (n=18) received normal saline. Hemodynamic parameters, blood gas analyses, and echocardiographic estimates of cardiac output were collected at baseline, 30 minutes post-CPB, at receiving in the Intensive Care Unit (ICU), and 6,12 and 24 hours after receiving in the ICU. The primary outcome was the cardiac index in the two groups at 30 minutes post-CPB. Cardiac index at 30 minutes post-CPB was not statistically significantly different between the two groups(3.22±1.44 l/minute/m2 in the vasopressin group vs. 2.64±0.88 l/minute/m2 in the control group, P=0.157). The heart rate and MAP were statistically significantly higher in the vasopressin group than the control group at 6 hours after receiving in ICU (102.55±17.92 vs. 86.67±15.15 beats per minute, P=0.007 and 72.50±8.60 vs. 66.17±9.08mm Hg, P=0.039, respectively). The diastolic blood pressure was statistically significantly higher in the vasopressin group than the control group at 12 and 24 hours after receiving in ICU (69.64±8.08 vs. 63.88±8.2 mm Hg, P=0.044 at 12 hours and 70.17±6.44 vs. 61.72±5.85mm Hg, P=0.001 at 24 hours). There was no statistically significant difference in the serum lactate, mixed venous oxygen saturation and delta-partial pressure of carbon dioxide between the two groups at any time. The fluid balance at 24 hours was statistically significantly lower in the vasopressin group than in the control group (15.20±27.77 vs. 34.69±12.60 ml/kg, respectively, P=0.11). The two groups had no statistically significant difference in the mechanical ventilation duration, ICU stay and 30-day outcome. No patient developed new-onset atrial fibrillation in the postoperative period in either group. The results of the present study indicate that the use of low dose vasopressin infusion in cardiac surgical patients with left ventricle dysfunction may not reduce the cardiac index at the end of cardiopulmonary bypass. Vasopressin infusion does not affect the clinical surrogates of cardiac output and clinical outcomes. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Visceral leishmaniasis in new foci areas of Nepal: Sources and extent of infection.
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Martschew, Eva, Al-Aghbari, Ahmed Asa’ad, Joshi, Anand Ballabh, Kroeger, Axel, Paudel, Krishna Prasad, Dahal, Gokarna, Pyakurel, Uttam Raj, Diaz-Monsalve, Sonia, and Banjara, Megha Raj
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- 2023
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26. Influence of Cr3C2 Addition on Microstructure and Mechanical Properties of AA2618 Composites by Powder Metallurgy.
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Borra, Naga Venkata Srinivas and Davuluri, Veera Venkata Krishna Prasad
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- 2023
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27. Population and Productivity of the Critically Endangered White-Rumped Vulture (Gyps bengalensis) in the Argha Important Bird and Biodiversity Area, Nepal.
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Bhusal, Krishna Prasad, Joshi, Ankit Bilash, Rana, Deu Bahadur, Thakuri, Deelip Chand, and McClure, Christopher J. W.
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The White-rumped Vulture (Gyps bengalensis) is an accipitrid vulture native to Asia. Once known as the world's most abundant large bird of prey, its population declined dramatically across its range during the 1990s. As a result, it is listed on the International Union for the Conservation of Nature (IUCN) Red List as critically endangered. From 2010 to 2021, we monitored two breeding colonies of White-rumped Vultures in the Argha Important Bird and Biodiversity Area, Arghakhanchi District, in the western mid-hill region of Nepal. We visited the colonies at least three times in each breeding season during November, February, and April and calculated nesting success. We estimated annual trends in number of occupied nests (i.e., nesting activity, egg, nestling, or adult in incubation posture), number of fledglings, and productivity (i.e., young fledged per occupied nest). The number of occupied nests, fledglings, and productivity were analyzed separately using identical models. Although the number of occupied nests appeared to increase, the credible interval of the growth rate (r) overlapped zero (r = 0.05, 95% CRI =–0.06–0.16). The number of fledglings (r = 0.04, 95% CRI = –0.04–0.16) and productivity (r < 0.01, 95% CRI = –0.08–0.09) appeared stable. Our findings are encouraging because they suggest stable population and productivity levels in the two breeding colonies of this critically endangered bird. However, our survey covered a small portion of the global population over a single generation of the species. We recommend coordinated, widespread, and long-term monitoring of vultures across South Asia. Gyps bengalensis es un buitre accipítrido originario de Asia. Considerada en su tiempo como el ave rapaz grande más abundante del mundo, su población disminuyó drásticamente en toda su área de distribución durante la década de 1990. Como resultado, se encuentra catalogada como en peligro crítico en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). De 2010 a 2021, seguimos dos colonias de cría de G. bengalensis en el Área Importante para las Aves y la Biodiversidad de Argha, distrito de Arghakhanchi, en la región occidental de colinas medias de Nepal. Visitamos las colonias al menos tres veces en cada temporada reproductiva durante noviembre, febrero y abril y calculamos el éxito de nidificación. Estimamos las tendencias anuales en el número de nidos ocupados (i.e., actividad de cría, huevo, polluelo o adulto en postura de incubación), el número de volantones y la productividad (i.e., polluelos emplumados por nido ocupado). El número de nidos ocupados, el número de volantones y la productividad se analizaron por separado usando modelos idénticos. Aunque el número de nidos ocupados pareció aumentar, el intervalo de credibilidad de la tasa de crecimiento (r) incluyó al cero (r=0.05, 95% ICR =–0.06 – 0.16). El número de volantones (r=0.04, 95% ICR=–0.04 – 0.16) y la productividad (r < 0.01, 95% ICR=–0.08 – 0.09) parecieron estables. Nuestros hallazgos son alentadores porque sugieren niveles estables de población y de productividad en las dos colonias de cría de este ave en peligro crítico. Sin embargo, nuestro muestreo cubrió una pequeña porción de la población mundial durante una sola generación de la especie. Recomendamos un seguimiento coordinado, generalizado y a largo plazo de los buitres en el sur de Asia. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]
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- 2023
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28. Hydrothermal doping of Ag and ZnO nanoparticles in Sterculiacellulose mat for antimicrobial and photocatalytic applications
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Kandel, Krishna Prasad, Aryal, Girja Mani, Adhikari, Menuka, Adhikari, Bhawani Prasad, Darden, Destiny, Joshi, Khem Raj, Joshi, Mahesh Kumar, Gautam, Bhoj Raj, and Neupane, Bhanu Bhakta
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Lignocellulose biomass is being used as starting material for wide range of applications. In this study, lignocellulose biomass obtained from Sterculia villosa(Roxb.), a traditionally important fibrous plant, was processed chemo-mechanically to get cellulose sheet. The sheet was then doped with Ag and ZnO nanoparticles following single-pot hydrothermal synthesis. The scanning electron microscopy (SEM) of the mat showed uniform distribution of the nanoparticles. The characteristic features of Ag and ZnO nanoparticles were observed in UV–Vis, XRD, and SEM–EDX data. These features were also found in the sonicated sample suggesting stable doping of the nanoparticles in the mat. Antimicrobial activity of the mat was tested for two bacterial (Escherichia coliand Bacillus subtilis) strains and a fungal (Candida albicans) strain, and showed good antimicrobial activity against E. coli. The mat also showed excellent photocatalytic property tested for degradation of methylene blue under UV irradiation. These findings suggested that multifunctional nanocomposite mat can be fabricated using Sterculia villosalignocellulose biomass which can be potentially used for antimicrobial packaging and water purification applications.
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- 2024
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29. Liquid chromatography and mass spectrometric studies of gilteritinib fumarate and characterization of its major degradation products by NMRElectronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d4ay01094a
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Vuyyala, Bhuvaneshwari, Pisini, Krishna Prasad, and Swain, Debasish
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Gilteritinib fumarate (GTB) is an anti-cancer drug belonging to the class of tyrosine kinase inhibitors used for the treatment of acute myeloid leukemia. It has been designated as an orphan drug by the US Food and Drug Administration (US FDA). The present research focused on carrying out the forced degradation studies of GTB and developing a UHPLC-PDA stability indicating method capable of separating GTB and its degradation products. The degradation studies were carried out under hydrolytic (acid, base, and neutral), oxidative, thermal, and light conditions. The drug degraded under hydrolytic and oxidative conditions whereas it was found to be stable under thermal and light exposure. The separation of the components was achieved on an Acquity BEH C18 column (2.1 × 100 mm; 1.7μ) and a mobile phase comprising ammonium acetate and acetonitrile eluting in gradient mode at a flow rate of 0.3 mL min−1. A total of five degradation products were obtained and were structurally characterized with the help of accurate mass and tandem mass experiments performed on LC-QTOF-MS equipment and DP-1 was isolated and characterized using 1D and 2D NMR experiments. The UHPLC-PDA method was validated as per the ICH Q2 (R1) guidelines for its accuracy, precision, linearity, and specificity. The method was found to be appropriate for its intended purpose and can be effectively used in the determination of GTB and its degradation products and/or impurities in bulk drugs as well as formulations.
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- 2024
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30. Digital assessment in higher education of Nepal: preference and practice
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Khadka, Jiban, Joshi, Dirgha Raj, Acharya, Deviram, and Adhikari, Krishna Prasad
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Digital assessment has been gaining momentum in educational institutions throughout the world. Considering the practice and preference of digital assessment, this study explores how students of higher education of Nepal perceive the digital assessment system implemented in higher education. The study was conducted among 422 students from Bachelor to MPhil levels of Nepal Open University applying a cross-sectional survey design. A questionnaire including the factors of support system, practicality, fairness, and preferences of digital assessment was developed and shared online to collect the responses. The factors were confirmed by the factor analysis. Then, mean, standard deviation, and structural equation modelling were used to analyse the data obtained from the questionnaire. The findings show that the overall perception of students towards the digital assessment system is positive, and the support system is effective in practicality and fairness, and largely the factors are interdependent to enhance the quality.
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- 2024
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31. PPR control program in Nepal: What next?
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Acharya, Krishna Prasad, Phuyal, Sarita, and Acharya, Narayan
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PPR is an economically important trans-boundary disease of sheep and goats. Nepal had experienced several episodes of PPR outbreaks in the past. Although severity and frequency of outbreaks have decreased due to strenuous effort of Government of Nepal, it has been rather endemic. National PPR Control Program 2001, and PPR Control Program Implementation Working Guidelines, 2013, the legal documents guiding PPR control activities, have not been effective as expected due to multifactorial reasons. Thus, a critical analysis of the program with emphasis on impeding factors is must. In this review, we attempted to analyse and suggest more effective strategies considering geopolitical, social and cultural context of Nepal.
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- 2024
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32. Barriers to Utilizing National Trust Act Programmes: A Qualitative Study of Caregivers of Children with Intellectual Developmental Disability (IDD)
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Mohan, Surjith, Reddy, Shanivaram K., and Muliyala, Krishna Prasad
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The Government of India introduced the National Trust Act (NTA) in 1999 for persons with autism, mental retardation [intellectual developmental disability (IDD)], cerebral palsy and multiple disabilities. There are ten schemes under the NTA. The current study focuses on understanding the barriers for family caregivers of persons with IDD in utilizing NTA schemes. A purposively selected sample of 10 caregivers of persons with IDD where qualitative in-depth interviews were conducted. Caregivers’ awareness of the NTA was poor. They were aware of only the Niramaya scheme and were not aware of the Niramaya scheme by name but rather as an insurance scheme. Among the various Government-funded welfare schemes, the respondents were aware of the disability pension. There is a need for intense focus and drive towards creating awareness of NTA schemes among families of persons with intellectual disabilities.
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- 2024
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33. IR regulation through preferential placement of h-BN nanosheets in a polymer network liquid crystalElectronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d3mh01467c
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Pisharody, Gayathri R., Sahoo, Priyabrata, Shankar Rao, D. S., Ramakrishna Matte, H. S. S., Sikdar, Debabrata, and Krishna Prasad, S.
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Recently, there has been a great deal of interest in devices which effectively shield near-infrared light with an additional feature of external field tunability, particularly for energy-saving applications. This article demonstrates an approach for fabricating a highly efficient near-infrared regulating device based on a polymer network liquid crystal reinforced with nanosheets of hexagonal-boron nitride (BN). The device achieves ∼84% IR scattering capability over a wavelength range of 800–2300 nm, and can also be regulated by an electric field. Interestingly, the observed high IR regulation is despite individual components of the composite being IR transparent, in stark contrast to earlier attempted incorporation of IR-absorbing/scattering particles. Detailed experimental characterization methods including FESEM corroborated with EDS and Raman spectroscopy suggest that the preferential positioning of the BN nanosheets, a consequence of the photo-polymerization process, is responsible for the observed feature. The IR reflectivity/back scattering that is doubled upon incorporation of the nanosheets results in an enhanced convective/radiative heat barrier capability, as evidenced by thermal imaging and significant (2 °C) reduction in ambient temperature upon one-Sun illumination. Numerical simulation results are also found to be in good agreement with the observed enhanced reflectance values for the BN-incorporated case. The presence of BN augments the mechanical rigidity of the system by a factor of 6.8 without compromising on the device operating voltage. The protocol employed is quite general and thus advantageous with far-reaching applications in passive cooling of buildings and structures, in thermal camouflaging, and in overall energy management.
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- 2024
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34. Unlocking Li superionic conductivity in face-centred cubic oxides via face-sharing configurations
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Chen, Yu, Lun, Zhengyan, Zhao, Xinye, Koirala, Krishna Prasad, Li, Linze, Sun, Yingzhi, O’Keefe, Christopher A., Yang, Xiaochen, Cai, Zijian, Wang, Chongmin, Ji, Huiwen, Grey, Clare P., Ouyang, Bin, and Ceder, Gerbrand
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Oxides with a face-centred cubic (fcc) anion sublattice are generally not considered as solid-state electrolytes as the structural framework is thought to be unfavourable for lithium (Li) superionic conduction. Here we demonstrate Li superionic conductivity in fcc-type oxides in which face-sharing Li configurations have been created through cation over-stoichiometry in rocksalt-type lattices via excess Li. We find that the face-sharing Li configurations create a novel spinel with unconventional stoichiometry and raise the energy of Li, thereby promoting fast Li-ion conduction. The over-stoichiometric Li–In–Sn–O compound exhibits a total Li superionic conductivity of 3.38 × 10−4S cm−1at room temperature with a low migration barrier of 255 meV. Our work unlocks the potential of designing Li superionic conductors in a prototypical structural framework with vast chemical flexibility, providing fertile ground for discovering new solid-state electrolytes.
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- 2024
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35. Conformational Properties of Aβ Peptide Oligomers in Aqueous Ionic Liquid Solution: Insights from Molecular Simulation Studies
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Sahoo, Subhadip, Pal, Tamisra, Mondal, Souvik, Ghanta, Krishna Prasad, and Bandyopadhyay, Sanjoy
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Alzheimer’s disease is a progressive irreversible neurological disorder with abnormal extracellular deposition of amyloid β (Aβ) peptides in the brain. We have carried out atomistic molecular dynamics simulations to investigate the size-dependent conformational properties of aggregated Aβ oligomers of different orders, namely, pentamer [O(5)], decamer [O(10)], and hexadecamer [O(16)] in aqueous solutions containing the ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]). The calculations revealed reduced peptide conformational fluctuations in O(5) and O(10) in the presence of the IL. In contrast, the higher order oligomer [O(16)] has been found to exhibit greater structural distortion due to enhanced flexibilities of its peptide units in the presence of the IL. Based on the distributions of the solvent (water) and the cosolvent (IL) components, it is demonstrated that exchange of water by the IL ion pairs at the exterior surface of the oligomers primarily occurs beyond the first layer of surface-bound water molecules. Importantly, a reduced number of relatively weaker peptide salt bridges have been found in O(16) in binary water-IL solution as compared to the other two smaller-sized oligomers [O(5) and O(10)]. Such differential influence of the IL on peptide salt bridges results in less favorable binding free energies of peptide monomers to O(16), which leads to its greater structural distortion and reduced stability compared to those of O(5) and O(10).
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- 2023
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36. Counteraction Effects of Ammonium-Based Ionic Liquids on Urea-Induced Denaturation of α‑Lactalbumin: A Comprehensive Molecular Simulation Study.
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Ghanta, Krishna Prasad and Bandyopadhyay, Sanjoy
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- 2023
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37. Enhanced Electrochemical Performance of Disordered Rocksalt Cathodes Enabled by a Graphite Conductive Additive.
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Patil, Shripad, Koirala, Krishna Prasad, Crafton, Matthew J., Yang, Guang, Tsai, Wan-Yu, McCloskey, Bryan D., Wang, Chongmin, Nanda, Jagjit, and Self, Ethan C.
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- 2023
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38. Exploring the Heterogeneous Dynamical Environment at the Interface of Aβ42 Peptide in Aqueous Ionic Liquid Solution.
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Pal, Tamisra, Sahoo, Subhadip, Ghanta, Krishna Prasad, and Bandyopadhyay, Sanjoy
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- 2023
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39. Enhancing the Electrode Gravimetric Capacity of Li1.2Mn0.4Ti0.4O2 Cathode Using Interfacial Carbon Deposition and Carbon Nanotube-Mediated Electrical Percolation.
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Xu, Jianan, Patil, Shripad, Koirala, Krishna Prasad, Chen, Weiyin, Campos-Mata, Astrid, Wang, Chongmin, Roy, Soumyabrata, Nanda, Jagjit, and Ajayan, Pulickel M.
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- 2023
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40. Influence of volute casing shape on centrifugal compressor performance
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Athul, P., Manu, S., Krishna, Prasad, Vishnu, P. M., Vysakh, V., and Ebin, P. S.
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- 2023
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41. Barriers to Vocational Rehabilitation in Adult Autism Spectrum Disorder: A Case Series from a Tertiary Mental Health Care Institute in India
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Mamtani, Harkishan, Singhai, Kartik, Ramachandraiah, Sujai, Jayarajan, Deepak, and Muliyala, Krishna Prasad
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- 2023
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42. Influence of Cr3C2Addition on Microstructure and Mechanical Properties of AA2618 Composites by Powder Metallurgy
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Borra, Naga Venkata Srinivas and Davuluri, Veera Venkata Krishna Prasad
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In the present work, Al-2.5Cu-1.5 Mg-1Ni (AA2618) aluminium alloy with the incorporation of Cr3C2reinforcement at 2, 3, 4 and 5 wt.% was systematically investigated. The composite powders were initially ball-milled and cold-compacted at 400 and 450 MPa. The pressure-less sintering was done at 550 and 600 °C for a holding time of 60 and 90 min under vacuum atmosphere. The experiments are implemented in accordance with Taguchi L8OA with four process factors and four response characteristics. The results indicate that significant microstructural refinement with the precipitation of new Al-Cr-C compound was noticed up to 4 wt.% of Cr3C2reinforcement, leading to tensile strength improvement at 28 and 200 °C. However, the strength was decreased at 5 wt.% Cr3C2reinforcement, which could be attributed to the presence of coarse grain structure and agglomerated large GB precipitate.
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- 2023
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43. Fabry–Perot Oscillation and Resonance Energy Transfer: Mechanism for Ultralow-Threshold Optically and Electrically Driven Random Laser in Quasi-2D Ruddlesden–Popper Perovskites.
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Bera, Krishna Prasad, Hanmandlu, Chintam, Lin, Hung-I, Ghosh, Rapti, Gudelli, Vijay Kumar, Lai, Chao-Sung, Chu, Chih-Wei, and Chen, Yang-Fang
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- 2023
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44. Microscopic Understanding of the Conformational Stability of the Aggregated Nonamyloid β Components of α‑Synuclein.
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Mondal, Souvik, Ghanta, Krishna Prasad, and Bandyopadhyay, Sanjoy
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- 2023
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45. Understanding the costs and economic impact of mental disorders in South Asia: A systematic review.
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McDaid, David, Vidyasagaran, Aishwarya Lakshmi, Nasir, Muhammed, Walker, Simon, Wright, Judy, Muliyala, Krishna Prasad, Thekkumkara, Sreekanth, Huque, Rumana, Faisal, Mehreen Riaz, Benkalkar, Saumit, Kabir, Mohammod Akbar, Russell, Claire, and Siddiqi, Najma
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Mental disorders remain the most significant contributor to years lived with disability in South Asia, yet governmental health expenditure on mental health in South Asia remains very low with limited strategic policy development. To strengthen the case for action it is important to better understand the profound economic costs associated with poor mental health. Methods: We conducted a systematic review on the costs of all mental disorders, as well as intentional self-harm and suicide, in the World Bank South Asia Region. Ten global and South Asian databases as well as grey literature sources were searched. Results: 72 studies were identified, including 38 meeting high quality criteria for good reporting of costs. Of these, 27 covered India, five Pakistan, four Nepal and three Bangladesh and Sri Lanka. Most studies focused on depressive disorders (15), psychoses (14) and harmful alcohol use (7); knowledge of economic impacts for other conditions was limited. Profound economic impacts within and beyond health care systems were found. In 15 of 18 studies which included productivity losses to individuals and/or carers, these costs more than outweighed costs of health care. Conclusion: Mental disorders represent a considerable economic burden, but existing estimates are conservative as they do not consider long-term impacts or the full range of conditions. Modelling studies could be employed covering longer time periods and more conditions. Clear distinctions should be reported between out-of-pocket and health system costs, as well as between mental health service-specific and physical health-related costs. • Governmental health expenditure on mental health in South Asia remains low. • Economic evidence can be used to support greater investment in mental health. • Profound economic impacts to government and families of depression and psychosis. • Critical to generate evidence for all mental disorders in all South Asian countries. • Modelling can be used to estimate longer term impacts of all mental disorders. [ABSTRACT FROM AUTHOR]
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- 2024
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46. Enhanced Electrochemical Performance of Disordered Rocksalt Cathodes Enabled by a Graphite Conductive Additive
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Patil, Shripad, Koirala, Krishna Prasad, Crafton, Matthew J., Yang, Guang, Tsai, Wan-Yu, McCloskey, Bryan D., Wang, Chongmin, Nanda, Jagjit, and Self, Ethan C.
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Cobalt-free cation-disordered rocksalt (DRX) cathodes are a promising class of materials for next-generation Li-ion batteries. Although they have high theoretical specific capacities (>300 mA h/g) and moderate operating voltages (∼3.5 V vs Li/Li+), DRX cathodes typically require a high carbon content (up to 30 wt %) to fully utilize the active material which has a detrimental impact on cell-level energy density. To assess pathways to reduce the electrode’s carbon content, the present study investigates how the carbon’s microstructure and loading (10–20 wt %) influence the performance of DRX cathodes with the nominal composition Li1.2Mn0.5Ti0.3O1.9F0.1. While electrodes prepared with conventional disordered carbon additives (C65 and ketjenblack) exhibit rapid capacity fade due to an unstable cathode/electrolyte interface, DRX cathodes containing 10 wt % graphite show superior cycling performance (e.g., reversible capacities ∼260 mA h/g with 85% capacity retention after 50 cycles) and rate capability (∼135 mA h/g at 1000 mA/g). A suite of characterization tools was employed to evaluate the performance differences among these composite electrodes. Overall, these results indicate that the superior performance of the graphite-based cathodes is largely attributed to the: (i) formation of a uniform graphitic coating on DRX particles which protects the surface from parasitic reactions at high states of charge and (ii) homogeneous dispersion of the active material and carbon throughout the composite cathode which provides a robust electronically conductive network that can withstand repeated charge–discharge cycles. Overall, this study provides key scientific insights on how the carbon microstructure and electrode processing influence the performance of DRX cathodes. Based on these results, exploration of alternative routes to apply graphitic coatings is recommended to further optimize the material performance.
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- 2023
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47. Counteraction Effects of Ammonium-Based Ionic Liquids on Urea-Induced Denaturation of α-Lactalbumin: A Comprehensive Molecular Simulation Study
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Ghanta, Krishna Prasad and Bandyopadhyay, Sanjoy
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Ionic liquids (ILs) are known to stabilize protein conformations in aqueous medium. Importantly, ILs can also act as refolding additives in urea-driven denaturation of proteins. However, despite the importance of the problem, detailed microscopic understanding of the counteraction effects of ILs on urea-induced protein denaturation remains elusive. In this work, atomistic molecular dynamics (MD) simulations of the protein α-lactalbumin have been carried out in pure aqueous medium, in 8 M binary urea–water solution and in ternary urea–IL–water solutions containing ammonium-based ethyl ammonium acetate (EAA) as the IL at different concentrations (1–4 M). Attempts have been made to quantify detailed molecular-level understanding of the origin behind the counteraction effects of the IL on urea-induced partial unfolding of the protein. The calculations revealed significant conformational changes of the protein with multiple free energy minima due to its partial unfolding in binary urea–water solution. The counteraction effect of the IL was evident from the enhanced structural rigidity of the protein with propensity to transform into a single native free energy minimum state in ternary urea–IL–water solutions. Such an effect has been found to be associated with preferential direct binding of the IL components with the protein and simultaneous expulsion of urea from the interface, thereby providing additional stabilization of the protein in ternary solutions. Most importantly, modified rearrangement of the hydrogen bond network at the interface due to the formation of stronger protein–cation (PC) and protein–anion (PA) hydrogen bonds by breaking relatively weaker protein–urea (PU) and protein–water (PW) hydrogen bonds has been recognized as the microscopic origin behind the counteraction effects of EAA on urea-induced partial unfolding of the protein.
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- 2023
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48. The State and the Madheshi Dalit Women’s Access to Citizenship in Nepal
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Pandey, Krishna Prasad
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The relationship between the state and Madheshi Dalit Womans (MDWs) with reference to the latter’s exercise of citizenship right has long been a contested issue in Nepal due to the latter’s alleged immigrant history and cultural and familial connection with the Dalits of Bihar and Uttar Pradesh of India. The MDWs who are at the lowest social order in Nepal because of their intersecting subordinate identities based on gender, caste, ethnic and class have been systematically excluded from the domain of Nepali citizenship during due course of hill-based national identity formation. Consequently, large number of the MDWs, their spouses and children have remained stateless or struggled hard to obtain citizenship owing to ethnic, caste, gender and class-based exclusion even after insertion of jus soliprovisos for a brief period in the 2006 Citizenship Act. On this backdrop, this article, based on qualitative field study in the eastern Tarai, is an effort to explore the intricacies of the citizenshiplessness of the MDWs of Nepal’s eastern Tarai from their subjective experiences. The findings reveal a disappointing picture of citizenshiplessness of the MDW families by virtue of multiple forms of exclusion and also a sustained hierarchy within themselves based on access to different types of citizenship.
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- 2023
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49. Exploring the Heterogeneous Dynamical Environment at the Interface of Aβ42Peptide in Aqueous Ionic Liquid Solution
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Pal, Tamisra, Sahoo, Subhadip, Ghanta, Krishna Prasad, and Bandyopadhyay, Sanjoy
- Abstract
In this study, we have investigated the heterogeneous dynamical environment around an ensemble of full-length amyloid-β (Aβ42) peptide monomers in binary aqueous solution containing the ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] as a co-solvent. Atomistic molecular dynamics (MD) simulations have been employed with the aim of understanding the effect of the IL on the distribution of water molecules and IL components around distinct segments of the peptide. As compared to pure aqueous medium, locally heterogeneous restricted water motions at the interface have been spotted in the presence of the IL. Our calculations revealed faster diffusion of water molecules hydrating hydrophilic segments (N-term and turn) as opposed to that around hydrophobic segments (hp1, hp2, and C-term). The extent of non-uniform restriction on the center-of-mass motions as well as the reorientation of water molecules and IL ions have been similarly affected in the binary IL–water solution. The effects of IL on the formation of hydrogen bond networks have been evident from the longer hydrogen bond relaxation time scales of peptide–water, with only a small fraction of peptide–anion hydrogen bonds contributing to the structural relaxation. Due to the size and shape factors, the increasingly sluggish dynamics of the IL components in the solvation shell can be attributed to a longer time scale for the onset of maximum dynamic heterogeneity. Interestingly, the water molecules around the polar segments of the peptide take longer to attain dynamic heterogeneity, which intensifies in the presence of IL. These calculations clearly suggest that electrostatic interaction plays a crucial role in water-mediated peptide–IL interaction, thereby shielding the surface from hydrophobic collapse and preventing possible further growth of the monomers into fibrils at higher peptide concentrations.
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- 2023
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50. Enhancing the Electrode Gravimetric Capacity of Li1.2Mn0.4Ti0.4O2Cathode Using Interfacial Carbon Deposition and Carbon Nanotube-Mediated Electrical Percolation
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Xu, Jianan, Patil, Shripad, Koirala, Krishna Prasad, Chen, Weiyin, Campos-Mata, Astrid, Wang, Chongmin, Roy, Soumyabrata, Nanda, Jagjit, and Ajayan, Pulickel M.
- Abstract
Mn-based cation-disordered rocksalt oxides (Mn-DRX) are emerging as promising cathode materials for next-generation Li-ion batteries due to their high specific capacities and cobalt- and nickel-free characteristic. However, to reach the usable capacity, solid-state synthesized Mn-DRX materials require activation via postsynthetic ball milling, typically incorporating more than 20 wt % conductive carbon that adversely reduces the electrode-level gravimetric capacity. To address this issue, we first deposit amorphous carbon on the surface of the Li1.2Mn0.4Ti0.4O2(LMTO) particles to increase the electrical conductivity by 5 orders of magnitude. Although the cathode material gravimetric first charge capacity reaches 180 mAh/g, its highly irreversible behavior leads to a first discharge capacity of 70 mAh/g. Subsequently, to ensure a good electrical percolation network, the LMTO material is ball-milled with a multiwall carbon nanotube (CNT) to obtain a 78.7 wt % LMTO active material loading in the cathode electrode (LMTO-CNT). As a result, a 210 mAh/g cathode electrode gravimetric first charge and 165 mAh/g first discharge capacity values are obtained, compared to the respective capacity values of 222 and 155 mAh/g for the LMTO material ball-milled with 20 wt % SuperP C65 electrode (LMTO-SP). After 50 cycles, LMTO-CNT delivers a 121 mAh/g electrode gravimetric discharge capacity, largely outperforming the value of 44 mAh/g of LMTO-SP. Our study demonstrates that while ball milling is necessary to achieve a significant amount of capacity of LMTO, a careful selection of additives, such as CNT, effectively reduces the required carbon quantity to achieve a higher electrode gravimetric discharge capacity.
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- 2023
- Full Text
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