158 results on '"Das, J."'
Search Results
2. Model-Based Single-Fault Disambiguation Using Temporal Information and Genetic Algorithm: A Case Study on Hydraulic Drive System.
- Author
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Kumar, Sawan, Ghoshal, Sanjoy K., and Das, J.
- Subjects
HYDRAULIC drive ,HYDRAULIC machinery ,TORQUE ,BUILDING sites ,PARAMETER estimation - Abstract
In this article, a special type of fault isolation problem is reported where temporal information is required for the estimation of parameters from susceptible fault sub-space. Any physical system always obeys certain mathematical constraints under the normal operating condition, and that is incorporated in a behavioral model, which is essentially flowing and force or moment balance. In a fault detection and identification (FDI) model, only concurrent states are known. In FDI, the constraint relationships need to be derived only in terms of known variables, i.e., the measurements and nominal parameters, which are termed analytical redundancy relations (ARRs). The numerical evaluation of ARRs is residuals, and those oscillate within a definite bound of error when computed using test data. In this work, a novel function is formulated using the ARRs at different time instants and that function is minimized to estimate the suspected parameter values belonging to the non-isolable sub-space. Single-fault hypothesis is considered, and a genetic algorithm (GA) is used for the optimization. This FDI analysis may be beneficial for power hydraulic-driven heavy machinery such as hydraulic excavators, dumpers, and front-end loaders, which are mostly used in mines and construction sites. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Earthquake-induced liquefaction potential and risk assessment of the world's largest mobile manufacturing plant, Noida, Uttar Pradesh.
- Author
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Kundu, P., Pain, A., and Das, J.
- Subjects
FACTORIES ,SOIL liquefaction ,RISK assessment ,UNDERGROUND construction ,INFRASTRUCTURE (Economics) ,EARTHQUAKE magnitude ,SEISMIC networks - Abstract
Evaluating liquefaction potential is essential for seismic micro-zonation for a specific area. Ground improvement of a site is conducted after the examination of the propensity of liquefaction of that site. The present study aims to evaluate the liquefaction potential and risk assessment for the world's largest mobile manufacturing Plant in Noida city, which comes under Gautam Buddha Nagar district (U.P.), India, for different magnitudes of earthquakes, i.e., 7.5, 7.0, and peak ground acceleration ( a max = 0.24 g). For this purpose, the factor of safety against liquefaction was evaluated at different depths from 32 boreholes and soil samples based on stress based approach derived from Idriss and Boulanger (Soil Dyn Earthq Eng 26:115–130, 2006) and the liquefaction potential risk index of the particular site was evaluated further. The results show that the study area is mainly comprised of silt and sand and falls under site class D (as per IBC International Code Council (2006) International building code (IBC). Washington, DC). The middle part of the study area shows high liquefaction potential. From the following analysis, 3D liquefaction potential risk models are prepared for classifying the boreholes from "very low" to "very high" (Iwasaki et al. in Proceedings of the 3rd international conference on microzonation, Seattle, vol 3, no 2, pp 1310–1330, 1982) along their depth. This rapid approach can be helpful for the future construction of earthquake-resilient structures and it may also help determine the risk of current underground structures like buried pipelines and metro railways, which are critical lifeline infrastructures of a city. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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4. Unveiling earthquake hazard in Noida, India: a combined probabilistic and deterministic seismic hazard assessment.
- Author
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Kundu, P., Das, J., Pain, A., and Pal, I.
- Published
- 2024
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- View/download PDF
5. History matters: societal acceptance of deep-sea mining and incipient conflicts in Papua New Guinea.
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van Putten, E.I., Aswani, S., Boonstra, W.J., De la Cruz-Modino, R., Das, J., Glaser, M., Heck, N., Narayan, S., Paytan, A., Selim, S., and Vave, R.
- Abstract
New marine industries that develop and grow in response to the changing demand for their products have the potential to exert pressure on fragile marine environments. These emerging industries can benefit local communities but equally can have negative environmental and socio-cultural impacts. The development of new and emerging industries, like deep seabed mining (DSM), requires the acceptance and involvement of local communities. Yet, the history of marine exploitation is imbued with conflicts between industries and local communities. This paper presents a DSM case study in Papua New Guinea (PNG) to stimulate debate around the potential for conflict in the pursuit of resource extraction from the deep sea and the social and environmental harm that these extractions can cause. We do so by first presenting a timeline of local and extra-local events and enabling conditions that form the development background for the DSM Solwara 1 project in PNG. We then undertake a media narrative analysis to consider the contribution of aspects of social acceptability to this highly complex and multi-scale conflict. We find that the lack of (or a decrease in) social acceptability contributed to the conflict situation and ultimately the demise of the Solwara 1 project. Extra-locally, the initial development was positively framed around solutions for decarbonisation using new technology. Over time, actions by international NGOs, financial issues related to foreign companies, and asymmetry in the power balance between the Pacific Island nation and global businesses played a role in growing negative perceptions of acceptability. Historical experiences with prior environmental mining disasters, together with sea tenure governance challenges, and a lack of community and stakeholder acceptance also contributed to the demise of the project. Untangling and debating these complex interactions provides context and reasons for the tension between the lack of societal acceptance at a local scale and the perceived need for DSM products in the global North for innovative technologies and decarbonising societies. Better understanding these interactions and tensions can help emerging industries navigate a future blue economy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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6. Thermal Anomaly, Co-Seismic Deformation and Seismic Source Parameters Estimation of June 21 2022, Afghanistan Earthquake Employing InSAR Observations.
- Author
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Panchal, Hardeep, Bahuguna, A., Saraf, Arun K., and Das, J.
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EARTHQUAKE aftershocks ,EARTHQUAKES ,PARAMETER estimation ,LAND surface temperature ,EARTH scientists ,TIME series analysis - Abstract
On June 21, 2022, a shallow earthquake of Mw 6.0 struck southeastern Afghanistan at the interaction of the Eurasian and Indian Plates. The earthquake was VIII (severe) intensity. It drew the attention of many seismologists and earth scientists. The presented work brings satellite-based detection of pre-earthquake transient thermal anomaly, co-seismic ground deformations estimation using InSAR (SAR Interferometry) and inversion of InSAR deformations results to estimate focal solution parameters. Near the Afghanistan earthquake, a rise of 5–7 °C from the normal temperature in both day and night Land Surface Temperature (LST) time series along the SW, NW, NE and east parts of the fault is observed using MODIS satellite thermal data. Sentinel-1A microwave satellite data with the InSAR technique is used to analyze co-seismic ground deformations for both passes, and the estimation of source parameters of the fault and slip distribution of the earthquake using the Bayesian inversion approach is carried out. InSAR-based ground deformations estimate upliftment of about 325 mm and subsidence of –160 mm. The inversion results of ground deformations show that the event might be occurred due to the left lateral slip mechanism. The fault seems to be steeply dipping in eastward with NE–SW trends at a depth of 7 km. A number of aftershocks have occurred till now in the regions as evident by the Coulomb static stress along the NE, east side of the fault. The correlation between high-stress regions using thermal anomaly before the occurrence of event and coulomb static stress map after the occurrence of event have been also observed. The total seismic moment for the event using the inversion result yields a value of 1.08 × 10
25 dyne-cm, which is equivalent to Mw 5.99. [ABSTRACT FROM AUTHOR]- Published
- 2023
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7. Performance analysis of a grid connected microgrid system under fault condition.
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Ghosh, Suman, Chanda, Chandan Kr., and Das, J. K.
- Subjects
MICROGRIDS ,ENERGY consumption ,SYSTEM analysis ,ELECTRICAL load ,GRIDS (Cartography) ,ELECTRON tube grids - Abstract
The energy demand in the modern power system is increasing day by day. Thus integration of microgrid with the conventional grid can fulfill the high power demand but it can cause many changes in the power system. In this paper, a real valued Damodar Valley Corporation (DVC) grid connected microgrid system is formed with the help of Power System Analysis Toolbox (PSAT) software and analyzed the performance by Continuous Power Flow (CPF) method. A three phase short circuit fault is also introduced in the main grid and voltage profile is observed. It is also observed that the voltage profile of the faulty system is improved when a microgrid is connected with that main DVC grid system. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Effect of Etching Parameters on Sensing Performance of Porous Silicon Thin Film Based Optical Biosensors.
- Author
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Basu, D., Das, J., and Hossain, S. M.
- Abstract
Performance of Porous silicon (PS) optical biosensors especially the ones which utilize reflectance based analysis, is dependent solely on surface morphology of the porous thin film. So for maximum sensitivity, study of output response with different PS morphology is inevitable. In this work, preparation parameters of electrochemical etching procedure have been varied to produce PS thin films of different morphological characteristics. Simple reflectance based optical sensing of glucose has been performed for all the samples to study dependence of the sensor response on these etching parameters. Thin film PS sensors were surface functionalized by physisorption of Glucose Oxidase (GOX) enzyme. The sensors were tested in pathological range of 1-20 mM and comparison of sensor response was performed for different thin film samples. Nano PS with 5 min etching time produced sensitive and reliable results with ∼ 90 s time response value, while macro PS samples produced non linear calibration curve with poor reproducibility and repeatability. Also, response time of macro PS samples was found to be ∼ 210 s which was significantly large compared to nano PS sensors. It was found that nano PS with 5 min etching time provides optimum performance in reflectance based optical glucose sensing. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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9. Cross-language contributions of rapid automatized naming to reading accuracy and fluency in young adults: evidence from eight languages representing different writing systems.
- Author
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Georgiou, George K., Cardoso-Martins, Claudia, Das, J. P., Falcón, Alberto, Hosokawa, Miyuki, Inoue, Tomohiro, Li, Yixun, Martinez, Dalia, Padakannaya, Prakash, Parrila, Rauno, Pollo, Tatiana C., Salha, Soheil S., Samantaray, Swagatika, Shu, Hua, Tanji, Takayuki, Tibi, Sana, and Vieira, Ana Paula Alves
- Published
- 2022
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10. Voltage Profile Management and Power Loss Minimization in a Real-Valued Conventional Grid-Connected Microgrid System with the help of Optimally placed PMUs.
- Author
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Ghosh, Suman, Chanda, Chandan Kr., and Das, J. K.
- Published
- 2022
- Full Text
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11. System identification and sizing of actuator of HEMM through response surface method of parameter estimation.
- Author
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Kumar, Sawan, Ghoshal, Sanjoy K., and Das, J.
- Published
- 2022
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12. Observation of superspin-glass behaviour and metamagnetic transition in spark plasma-sintered Ni50−xCoxMn40Sn10 (x = 3, 5, 7, and 9 at.%).
- Author
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Anand, K. S., Goswami, D., and Das, J.
- Published
- 2022
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13. 32nd Mineral Development Awareness Program-2023 by the Society of Geoscientists and Allied Technologists (SGAT), Bhubaneswar, Odisha.
- Author
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Mohanta, Trilochan, Mohanty, Sujit, and Das, J. N.
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EARTH scientists ,MINERALS ,TECHNOLOGISTS ,COLLEGE curriculum ,DISTRIBUTION (Probability theory) - Abstract
The Society of Geoscientists and Allied Technologists (SGAT) organized the 32nd Mineral Development Awareness Program (MDAP) in Odisha, India. The three-day event aimed to expose students pursuing geoscience and mining-related courses to the latest developments in their fields, with a focus on mining environment, its impact, and restoration. Sixty students from various academic institutions participated in the program, visiting mines and engaging in activities such as identifying rocks and minerals. The program received support from government departments, mining companies, and local mining authorities. The event was considered successful, and participants expressed gratitude for the practical exposure they gained. [Extracted from the article]
- Published
- 2023
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14. Genome-wide identification and expression analysis of the plant specific LIM genes in Gossypium arboreum under phytohormone, salt and pathogen stress.
- Author
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Raghavendra, K. P., Das, J., Kumar, R., Gawande, S. P., Santosh, H. B., Sheeba, J. A., Kranthi, S., Kranthi, K. R., and Waghmare, V. N.
- Subjects
- *
PLANT hormones , *PATHOGENIC microorganisms , *PLANT species , *ZINC-finger proteins , *ABSCISIC acid - Abstract
Asiatic cotton (Gossypium arboreum) cultivated as 'desi cotton' in India, is renowned for its climate resilience and robustness against biotic and abiotic stresses. The genome of G. arboreum is therefore, considered as a valued reserve of information for discovering novel genes or gene functions for trait improvements in the present context of cotton cultivation world-wide. In the present study, we carried out genome-wide analysis of LIM gene family in desi cotton and identified twenty LIM domain proteins (GaLIMs) which include sixteen animals CRP-like GaLIMs and four plant specific GaLIMs with presence (GaDA1) or absence (GaDAR) of UIM (Ubiquitin Interacting Motifs). Among the sixteen CRP-like GaLIMs, eleven had two conventional LIM domains while, five had single LIM domain which was not reported in LIM gene family of the plant species studied, except in Brassica rapa. Phylogenetic analysis of these twenty GaLIM proteins in comparison with LIMs of Arabidopsis, chickpea and poplar categorized them into distinct αLIM1, βLIM1, γLIM2, δLIM2 groups in CRP-like LIMs, and GaDA1 and GaDAR in plant specific LIMs group. Domain analysis had revealed consensus [(C-X2-C-X17-H-X2-C)-X2-(C-X2-C-X17-C-X2-H)] and [(C-X2-C-X17-H-X2-C)-X2-(C-X4-C-X15-C-X2-H)] being conserved as first and/or second LIM domains of animal CRP-like GaLIMs, respectively. Interestingly, single LIM domain containing GaLIM15 was found to contain unique consensus with longer inter-zinc-motif spacer but shorter second zinc finger motif. All twenty GaLIMs showed variable spatio-temporal expression patterns and accordingly further categorized into distinct groups of αLIM1, βLIM1, γLIM2 δLIM2 and plant specific LIM (DA1/DAR). For the first time, response of GaDA1/DAR under the influence of biotic and abiotic stresses were studied in cotton, involving treatments with phytohormones (Jasmonic acid and Abscisic acid), salt (NaCl) and wilt causing pathogen (Fusarium oxysporum). Expressions patterns of GaDA1/DAR showed variable response and identified GaDA2 as a probable candidate gene for stress tolerance in G. arboreum. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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15. Professor C. K. Leong: in memoriam.
- Author
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Kirby, John R., Georgiou, George K., Chen, Xi, Parrila, Rauno, and Das, J. P.
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LEXICAL access ,ORTHOGRAPHY & spelling ,SPECIAL education ,EDUCATIONAL psychology - Abstract
Professor Che Kan (C. K.) Leong was a Canadian educational psychologist specializing in special education and dyslexia in the Faculty of Education at the University of Saskatchewan. Stimulated by his understanding of the morphological structure of Chinese, C. K. was one of the first to explicitly address the role of morphology in reading (Leong, [1], [7]; Leong, Cheng & Mulcahy, [19]) and reading difficulties (Leong, [8]; Leong, [10]; Leong & Parkinson, [17]). Che Kan Leong (known to all as C. K.) was born in Canton, China, on May 10, 1931. [Extracted from the article]
- Published
- 2021
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16. Optical and resistive switching properties of Chitosan-aluminum-doped zinc oxide composite thin films for transparent resistive random access memory application.
- Author
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Vallabhapurapu, Sreedevi, Sangani, L. D. Varma, Krishna, M. Ghanashyam, Das, J., Srinivasan, A., and Srinivasu, V. V.
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ZINC oxide thin films ,NONVOLATILE random-access memory ,RANDOM access memory ,OPTICAL switching ,LIGHT transmission ,ZINC oxide - Abstract
The preparation of chitosan-aluminum-doped zinc oxide (AZO) composite thin films for transparent resistive random access memory applications is reported. The variation in optical transmission, refractive index and optical bandgap of the composite films as a function of concentration of Al in ZnO and AZO weight percent in chitosan is investigated. Independent of composition, optical transmission is of the order of 87–89% at 550 nm. The refractive index at this wavelength is in the range of 1.71–1.86. The composite films exhibit reversible resistive switching behavior which is dependent on the Al concentration in ZnO as well as the weight percent of AZO in chitosan. There is a threshold Al concentration in ZnO, below and above which resistive switching is not observed. At the threshold concentration, resistive switching behavior is stable over several cycles. The co-existence of unipolar and bipolar switching controlled by Al concentration in ZnO is also observed. The current study establishes the potential of chitosan-AZO composite thin films for transparent resistive random access memory application. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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17. Transarterial chemoembolization for hepatocellular carcinoma: a bibliometric analysis of the most cited articles.
- Author
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Das, J. P., Thulasidasan, N., Ahmed, I., and Diamantopoulos, A.
- Abstract
Purpose: Bibliometric analysis is a quantitative assessment of the academic literature in a particular field. The aim of our study was to characterize the 100 top-cited articles regarding transarterial chemoembolization (TACE) for the treatment of hepatocellular carcinoma (HCC). Materials and methods: The 'Web of Science' database was used to identify the leading articles regarding TACE for HCC. We determined the top 100 articles according to citations and performed an analysis on year of publication, authorship, department affiliation, publishing journal, institution and country of origin, subject matter and article type. Results: The top-cited articles received between 92 and 2254 citations (median 283.4). The top 100 papers were published in 32 journals between 1983 and 2016. Cancer, Radiology and Hepatology published the most articles (n = 40). Internal medicine was the department affiliation of the first author in 49%. The country providing the most highly cited articles was Japan (n = 24). Conclusion: We performed an analysis of the 100 top-cited articles dealing with TACE for HCC, presenting a detailed list of the most influential and historically significant papers. Japan was the country that produced the most top-cited articles, highlighting its key contribution to this field of the literature. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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18. Effect of Moist Air and Minor Zr Addition on Oxidation Behavior of Arc-Melted Multiphase Mo–Si–B Alloys in the Temperature Range of 1000 °C–1300 °C.
- Author
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Kumar, N. K., Das, J., and Mitra, R.
- Subjects
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KIRKENDALL effect , *MOLYBDENUM disilicide , *ALLOYS , *OXIDATION , *AIR , *SCANNING electron microscopy , *METALLIC glasses - Abstract
Arc-melted multiphase intermetallic alloys, Mo76Si14B10, Mo74Si14B10Zr2, Mo79.5Si12B8.5 and Mo77.5Si12B8.5Zr2 with microstructures containing Moss, Mo3Si and Mo5SiB2 were isothermally exposed for 1 h or 24 h at 1000 °C, 1150 °C and 1300 °C in dry or moist air. The residual area fraction was found to be the highest on exposure at 1150 °C in dry air, but the least at this temperature in moist air. Examination of dry air formed oxide scales by X-ray diffraction, and scanning electron microscopy with energy-dispersive spectroscopy showed the presence of Mo, and MoO2 with a continuous, protective glassy B2O3–SiO2 top layer. Formation of Zr(MoO4)2 in the Zr-containing alloys had lowered mass loss by arresting MoO3 vaporization, and had enhanced the B2O3–SiO2 scale formation kinetics. Further, Si(OH)4, cristobalite, H3BO3 and MoO3·(H2O)2 appeared to be constituting the oxidation products formed in moist air. Alloying with Zr enhanced the kinetics of protective scale formation by lowering the Moss content, and microstructural refinement. The deterioration of oxidation resistance in moist air was conjectured to be due to longer duration required for protective scale to form, formation of β-cristobalite permitting grain boundary diffusion of oxygen anions, as well as volatile hydrated oxidation products as mentioned above. Formation of ZrSiO4 and dissolved ZrO2 in B2O3–SiO2 scale of the Mo-Si-B-Zr alloys in both dry air and moist air is considered to have contributed to the enhanced protective character of oxide scale by stabilizing the glassy scale. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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19. Cultural influences on the relation between executive functions and academic achievement.
- Author
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Georgiou, George K., Wei, Wei, Inoue, Tomohiro, Das, J. P., and Deng, Ciping
- Subjects
CULTURAL relations ,SOCIOCULTURAL factors ,ACADEMIC achievement ,STRUCTURAL equation modeling ,SHORT-term memory - Abstract
The purpose of this study was to examine which of the components of executive functions (EF)—inhibition, shifting, and working memory—predict reading and mathematics achievement and if the effects of these components are the same across two cultures (Western and East Asian). One hundred twenty English-speaking Canadian (65 females, 55 males; M
age = 82.12 months) and 181 Mandarin-speaking Chinese (82 females, 99 males; Mage = 85.85 months) children were assessed on nonverbal IQ, speed of processing, rapid naming, inhibition (Color-Word Stroop), shifting (Planned Connections), working memory (Digit Span Forward and Backward), reading (word identification and reading comprehension), and mathematics (numerical operations and math reasoning). The results of structural equation modeling indicated first that among the EF components only working memory predicted reading and mathematics in the Canadian sample, while inhibition and working memory predicted reading and mathematics in the Chinese sample. The results also showed that inhibition was a stronger predictor of reading and mathematics in the Chinese sample. Taken together, these findings suggest that not all EF components are equally important for reading/mathematics and that culture may influence the relations between specific EF components and academic achievement. [ABSTRACT FROM AUTHOR]- Published
- 2020
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20. Placement of phasor measurement unit for complete observability of an isolated microgrid system.
- Author
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Ghosh, Suman, Das, J. K., and Chanda, Chandan Kr.
- Subjects
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PHASOR measurement , *MICROGRIDS , *BUSES - Abstract
The role of the microgrid to meet up the localized power demand is of immense importance considering the growing power demand as well as grid inadequacy in Indian power scenario. Apart from meeting localized power demand with various distributed generating sources microgrid can render support to the adjacent main grid or similar localized grid as when needed. This paper presents the techniques for identifying placement sites for Phasor Measurement Units (PMUs) in a microgrid system based on complete observability of the system. The main objective of optimal placement of PMU problem is to determine a minimal set of PMUs such that the whole system is observable. This study has been done on a 14 bus test model with the help of PSAT. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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21. Nonchiral Bosonization of Strongly Inhomogeneous Luttinger Liquids.
- Author
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Das, J. P., Chowdhury, C., and Setlur, G. S.
- Subjects
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LUTTINGER liquids , *GREEN'S functions , *EQUATIONS of motion , *PERTURBATION theory , *RENORMALIZATION group - Abstract
Nonchiral bosonization (NCBT) is a nontrivial modification of the standard Fermi—Bose correspondence in one spatial dimension done to facilitate studying strongly inhomogeneous Luttinger liquids where the properties of free fermions plus the source of inhomogeneities are reproduced exactly. We introduce the NCBT formalism and discuss limit case checks, fermion commutation rules, point-splitting constraints, etc. We expand the Green's functions obtained from NCBT in powers of the fermion—fermion interaction strength (only short-range forward scattering) and compare them with the corresponding terms obtained using standard fermionic perturbation theory. Finally, we substitute the Green's functions obtained from NCBT in the Schwinger—Dyson equation, which is the equation of motion of the Green's functions and serves as a nonperturbative confirmation of the method. We briefly discuss some other analytic approaches such as functional bosonization and numerical techniques like the density-matrix renormalization group, which can be used to obtain the correlation functions in one dimension. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
22. Effect of Zr Addition on Microstructure, Hardness and Oxidation Behavior of Arc-Melted and Spark Plasma Sintered Multiphase Mo-Si-B Alloys.
- Author
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Kumar, N. K., Das, J., and Mitra, R.
- Subjects
ZIRCONIUM alloys ,MICROSTRUCTURE ,OXIDATION ,HEAT resistant alloys ,JET engines - Abstract
The effect of 2 at. pct Zr addition at the expense of Mo on microstructural evolution, hardness as well as non-isothermal and isothermal oxidation behavior of arc-melted or spark-plasma sintered (SPS) 76Mo14Si10B and 79.5Mo12Si8.5B alloys, has been examined. The microstructures of both arc-melted and SPS alloys have exhibited α-Mo, Mo
3 Si and Mo5 SiB2 .These alloys, particularly those processed by SPS have also shown dispersion of SiO2 particles, and these are largely replaced by ZrO2 at interphase boundaries in the Zr-containing alloys. Alloying with Zr or processing by SPS has led to refinement of microstructure, which in turn has caused significant hardness enhancement. During heating from ambient temperature to 1250 °C in air inside a thermogravimetric analyzer, initial mass gain at ≈ 800 °C is found to be followed by rapid mass loss. Isothermal oxidation studies in the temperature range of 800 °C-1300 °C have shown initial mass loss caused by vaporization of MoO3 being followed by a regime of no change in mass. Besides B2 O3 -SiO2 , MoO2 and Mo have been found in the oxide scales of all alloys, whereas ZrO2 and ZrSiO4 have been found along with Zr(MoO4 )2 in case of Zr-containing alloys. Reduced mass loss is observed in Zr-containing alloys with the maximum improvement being observed for exposure at 800 °C, not only due to higher volume fractions of Mo3 Si and Mo5 SiB2 contributing to formation of B2 O3 -SiO2 , but also because MoO3 is partly consumed to form non-volatile Zr(MoO4 )2 . Furthermore, refinement of microstructures obtained by Zr addition or processing by SPS increases the net area covered by interphase interfaces, which provides short circuit paths for diffusion and enhances the kinetics of formation of protective B2 O3 -SiO2 scale. [ABSTRACT FROM AUTHOR]- Published
- 2019
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23. Fuel Cell Technologies for Defence Applications.
- Author
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Narayana Das, J.
- Published
- 2017
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24. Application of Parallel Multi-model Simulation Method for Condition Monitoring of a Power Hydraulic System.
- Author
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Mishra, Santosh Kr., Tripathi, Jay Prakash, Das, J., and Ghoshal, Sanjoy K.
- Subjects
HYDRAULICS ,HYDROSTATICS ,PARAMETER estimation - Abstract
In hydraulic system, the occurrence of fault is a common phenomenon which mainly results due to abnormal behavior of its decisive components leading to sudden alarming rise in some of its critical parameters, and hence, the need for condition monitoring techniques arises. Residuals which happen to be an indicator of faulty signal are equivalent to the number of sensors set up in the plant. Hence, the need is to place in considerable number of sensors throughout the plant to create residuals, a prime requisite required for isolating fault. But it appears a tedious task and seems technically improbable to isolate all potential faults with the instruments at our disposal, and it can turn out to be an expensive affair to put inexact number of sensors in order to evaluate individually every physical state. To tackle with such problem, an already-developed methodology has been implemented on the test setup, i.e., a closed-loop hydrostatic transmission system consisting of a variable-displacement pump and a fixed displacement motor. In this way, an experimental exposure is added to the revisited methodology which was lacking. Moreover, the parameter estimation technique in the revisited methodology is modified to tackle with the situations where the generation of symbolic expression for estimating the suspected parameters is not trivial due to nonlinearity in equation. Therefore, the estimation problem is resolved numerically in Simulink. Due to same reason of the absence of symbolic expression, the observer-based residual is generated instead of ARR-based residual. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
25. PID controller with feed forward estimation used for fault tolerant control of hydraulic system.
- Author
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Mishra, Santosh Kr., Wrat, Gyan, Ranjan, Prabhat, and Das, J.
- Subjects
FAULT tolerance (Engineering) ,FREQUENCIES of oscillating systems ,LOADING & unloading ,PID controllers ,RESPONSE rates - Abstract
The paper stresses on the designing and implementation of a nonlinear offline feed forward controller in association with a PID controller as a fault tolerant control measure for a closed loop hydraulic system. An off-line nonlinear feed forward control with proportional pressure relief valve (PRV) loading on the loading pump has been developed using the subsystem models without taking into considerations the oil compressibility, valve dynamics and leakages associated with various components of the hydraulic circuit. A PID feedback has been utilized in real-time to deal with the unmodeled features and the modelling approximations. The characteristics of the speed response are significantly influenced by the disturbances related to external torque, change in the input magnitude as well as system parameters like inertia load and supply pressure. The real-time control showed that the experimental and predicted closed-loop control performances justify each other quite well. Hence, the PID gains were estimated quite effectively with the help of the developed simulation tool here. The control model produced good agreement between the demanded and real-time speed response for various loading conditions such as step load, sinusoidal load, variable load, triangular load etc. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
26. Free Convective Flow, Heat and Mass Transfer in a Micropolar Fluid Over a Shrinking Sheet in the Presence of a Heat Source.
- Author
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Mishra, S. R., Mohanty, J., and Das, J. K.
- Subjects
HEAT transfer ,MASS transfer ,CONVECTIVE flow ,THERMAL expansion ,THERMODYNAMICS - Abstract
The paper considers a free convective flow of a micropolar fluid in the presence of a heat source/sink over a shrinking sheet. Similarity transformations are used to reduce the governing coupled nonlinear partial differential equations, namely, the momentum and concentration equations, as well as the nonhomogeneous heat equation, to a set of nonlinear ordinary differential equations. Their numerical solution is obtained by the Runge-Kutta fourth-order method accompanied by the shooting technique. The effects of various physical parameters characterizing the flow are studied. The validation of the present results by the earlier published ones is performed in a particular case, and good agreement is obtained. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
27. Bond graph modelling of a hydraulic cylinder-actuated planar manipulator.
- Author
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Tripathi, Jay, Ghoshal, Sanjoy, Dasgupta, K., and Das, J.
- Published
- 2017
- Full Text
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28. 31st Mineral Development Awareness Program-22 by Society of Geoscientists and Allied Technologists (SGAT), Bhubaneswar, Odisha.
- Author
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Panigrahi, Alok Bihari, Mohanta, Trilochan, and Das, J. N.
- Subjects
EARTH scientists ,MINERALS ,TECHNOLOGISTS ,COLLEGE curriculum ,ATMOSPHERIC sciences - Published
- 2022
- Full Text
- View/download PDF
29. Tower of London: What Level of Planning Does it Measure?
- Author
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Georgiou, George, Li, Jian, and Das, J.
- Abstract
We examined which of two levels of planning, namely action and operations planning, are involved in Tower of London (TOL). One hundred nine university students (79 females; mean age = 20.81 years) from China were assessed on measures of action planning (Crack the Code), operations planning (Planned Connections, Planned Codes, Matching Numbers), and on TOL. The results of factor analysis showed first that TOL, scored as total number of correct responses, had a split loading on action and operations planning. TOL, scored as first move time, loaded on the same action planning factor represented by Crack the Code first move time. These findings suggest that different TOL scores may capture different levels of planning. The implications of these findings especially for clinical diagnosis and rehabilitation are briefly discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
30. Non-Resonant Microwave Absorption in SmFeAs O F : Line Shape and Structure Evolution with Temperature.
- Author
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Onyancha, R., Shimoyama, J., Das, J., Hayashi, K., Ogino, H., and Srinivasu, V.
- Subjects
MICROWAVES ,POLYCRYSTALS ,SUPERCONDUCTIVITY ,SAMARIUM compounds ,HYSTERESIS - Abstract
'Non-resonant Microwave Absorption' (NRMA) or the 'Low field microwave absorption' (LFMA) measurements on high-quality polycrystalline SmFeAsOF superconducting sample were carried as functions of temperature and microwave power. The LFMA line shape is complex with two peaks namely; broad peak 1 and narrow peak 2 akin to one reported in SmFeAsOF as reported by Onyancha et al (Supercond. Nov. Magn. 28, 2927-2934, 2015). This unquestionably illustrates that these peaks are a common feature in F-doped SmFeAsO. The LFMA signal as a function of temperature reveals that T − T = 1K in SmFeAsOF compared to 4 K in SmFeAsOF ( T is the characteristic temperature at which the narrow peak appears as we cool down the sample below T ); hence inferring that the narrow peak is fluorine doping dependent. Furthermore, LFMA signal evolution with microwave power does not show phase reversal (anomalous absorption) at 2.227 mW which is a stark contrast to what was observed in SmFeAsOF as reported by Onyancha et al (Physica C: Supercond. Appl. 533:49-52, 2017). The absence of phase reversal within measured microwave power indicates presence of hysteretic Josephson junction. These findings establish few non-superconducting inclusions in SmFeAsOF system. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
31. Influence of graphene growth temperature by chemical vapour deposition on the hydrogen response of palladium-graphene junction.
- Author
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Dutta, D., Das, J., Hazra, S., Sarkar, C., and Basu, S.
- Subjects
RAMAN spectroscopy ,MOLECULAR spectroscopy ,PALLADIUM ,CLASS B metals ,HYDROGEN analysis - Abstract
The hydrogen sensing by palladium-graphene junction was dependent on the atmospheric pressure chemical vapour deposition growth temperature of the graphene films. The growth temperature window adopted in this study was 900-1000 °C, and the hydrogen sensor performance of the palladium-graphene junction (0.5-2.0% H in air) was studied in the temperature range 30-150 °C. Raman spectroscopy study with the as grown graphene films revealed the multilayer nature and the Pd-graphene planar structure showed a temperature dependent n- to p-type conductivity change in presence of hydrogen. Such a conductivity transition in presence of a reducing gas like hydrogen was experimentally studied in detail, and the hydrogen sensor results were correlated with the multilayer character of the graphene thin film, which induces hydrogen intercalation between the graphene layers. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
32. Electron Spin Resonance Study of Co-doped ZnO System: Spin-Canted Magnetism and Sintering Effects.
- Author
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Mahule, T, Srinivasu, V., and Das, J.
- Subjects
ELECTRON paramagnetic resonance ,SINTERING ,MAGNETIC anisotropy ,FERROMAGNETISM ,MAGNETIZATION - Abstract
We report on the electron spin resonance (ESR) studies in the Mn:Ni and Mn:Gd co-doped ZnO system sintered at 500 and 800 °C. We found that sintering temperature has strong effect on the ESR line widths, with the Mn-Gd co-doped ZnO system showing the largest effect. Increasing sintering temperature has increased the line widths considerably, running into Kilo Oersted range. These large line widths indicate magnetic in-homogeneities and disorder and are consistent with the occurrence of secondary phases due to high-temperature sintering. Further analysing the asymmetry parameters, together with Δ g/ g-values, we explain the weak ferromagnetism at low temperatures in 500°C sintered Mn:Gd-ZnO system to be due to spin canting which is the parasitic or the 'spin-canted magnetism'. The ESR line intensity which is the spin susceptibility shows a paramagnetic behaviour in the range 300-100 K and shows a sharp rise and a peak around 40 K consistent with the magnetization data reported earlier. In the case of Mn:Ni-ZnO system, the Δ g/ g and P parameters, which are proportional to spin canting and magneto-crystalline anisotropy, closely follow each other representing the classic picture of Moriya-Dzyaloshinsky. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
33. Non-resonant Microwave Absorption in Nano Nickel Added YBCO Powders: Observation of Multiple Phase Reversals.
- Author
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Nemangwele, F., Sankaran, V., Roul, B., Das, J., and Srinivasu, V.
- Subjects
NICKEL ,NANOPARTICLES ,JOSEPHSON junctions ,FERROMAGNETIC materials ,TEMPERATURE - Abstract
We report on the non-resonant microwave absorption in the system of a nominal 2 wt % nano nickel particles added into YBCO powders (Ni-YBCO). With this dilute mixture of nano nickel particles, one is expected to have groups of normal Josephson junctions (JJs) and π JJs due to YBCO-nickel-YBCO interparticle weak links and as nickel is ferromagnetic. We experimentally show, for the first time multiple phase reversals in the non-resonant microwave absorption (NRMA) spectra from Ni-YBCO possibly due to the formation of π JJs. We also showed that these multiple phase reversals then depend on microwave power and temperature. We argue that microwave power induced coherence among some groups of JJs and breaking of some of the weaker JJs can then lead to the disappearance of multiple phase reversals at higher microwave power levels. Further, we also reported a role of pair breaking effects that shall give a linear field dependence of the derivative microwave absorption signal, essentially which is the NRMA signal. This pair breaking effect dominates at closer temperatures to T which is expected thermodynamically. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
34. Nonlinear modeling and PID control through experimental characterization for an electrohydraulic actuation system: system characterization with validation.
- Author
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Das, J., Mishra, Santosh, Saha, R., Mookherjee, S., and Sanyal, D.
- Published
- 2017
- Full Text
- View/download PDF
35. Electron Spin Resonance Studies of Undoped and Dysprosium Doped Bismuth Ferrite Nanoparticles.
- Author
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Titus, S., Srinivasu, V., Balakumar, S, Sakar, M., and Das, J.
- Subjects
ELECTRON paramagnetic resonance ,DYSPROSIUM ,SEMICONDUCTOR doping ,MAGNETIC properties of bismuth ,MAGNETIC properties of nanoparticles - Abstract
The magnetic state of multiferroic Bi Dy FeO (where x = 0.0, 0.05) nanoparticles that synthesized by the sol-gel method has been probed by electron spin resonance (ESR) spectroscopy. Systematic analysis of the obtained ESR spectra revealed that the strong signal with asymmetric line shape is due to the cycloidal spin structure in the bismuth ferrite (BFO) system. While the magnetic behaviour of BFO is intriguing with conflicting reports that attribute to its 'spin glass' and 'domain pinning' effects etc., our ESR data of line width temperature independence supports the spin glass scenario. Further, we have observed a dip or minimum with a narrow valley in the temperature dependence of Δ g/ g at 75 K for Bi Dy FeO (BDFO), indicating an abrupt disruption and decrease of canting spin order at that particular temperature. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
36. Surface topography and hydrogen sensor response of APCVD grown multilayer graphene thin films.
- Author
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Dutta, D., You, Y., Sinha, S., Bontempi, E., Das, J., Hazra, S., Sarkar, C., and Basu, S.
- Subjects
RAMAN spectroscopy ,GRAPHENE ,SURFACE topography ,CHEMICAL vapor deposition ,HYDROGEN detectors ,ANALYTICAL chemistry techniques - Abstract
Atmospheric pressure chemical vapour deposition was employed to deposit graphene thin films on thermally oxidized p-silicon substrates. Raman spectroscopy and energy dispersive spectroscopy revealed the multilayer nature and the composition of the grown graphene films respectively. The defective nature and the defect density of the graphene films were determined from the Raman experiments. Field effect scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to study the surface morphology of the multilayer graphene films. The film topography was sensitive to temperature and time of growth. A suitable growth mechanism has been proposed to explain the topographical observations. The large surface area of the multilayer films was found to be suitable for hydrogen sensor applications and the sensing results were correlated with the morphology of the grown films. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
37. Temperature- and Hydrogen-Gas-Dependent Reversible Inversion of n-/ p-Type Conductivity in CVD-Grown Multilayer Graphene (MLG) Film.
- Author
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Dutta, D., Hazra, S., Das, J., Sarkar, C., and Basu, S.
- Subjects
THERMAL properties ,POLYCYCLIC aromatic hydrocarbons ,HYDROGEN ,GRAPHENE ,TWO-dimensional materials (Nanotechnology) ,TEMPERATURE control - Abstract
In atmospheric-pressure chemical vapor deposition-grown multilayer graphene films, a reversible change from n- to p-type conductivity has been observed in the temperature range of 25°C to 150°C upon exposure to hydrogen. This study was conducted with a simple Pd/graphene/Pd planar device. The inversion was observed at around 100°C, below which it showed stable n-type response to hydrogen. The hydrogen response was quite fast (1 s to 2 s) at 150°C. A plausible mechanism has been developed to explain such inversion. The selectivity and stability of the device in both n- and p-regions were investigated in the temperature range of 25°C to 150°C. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
38. Ar/Ar and cosmic ray exposure ages of plagioclase-rich lithic fragments from Apollo 17 regolith, 78461.
- Author
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Das, J., Baldwin, S., and Delano, J.
- Published
- 2016
- Full Text
- View/download PDF
39. Nanoeutectic Composites: Processing, Microstructure and Properties.
- Author
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Das, J., Maity, T., and Singh, A.
- Abstract
Nanostructured alloys exhibit high strength and large elastic strain limit. Unfortunately, the plasticity of these alloys is disappointingly low at room temperature than that of the coarse grain counterparts. In this work, a series of nanoeutectic composites have been developed in Ti-Fe and Ni-Zr based alloys, which exhibit very high strength, like bulk metallic glasses and large plasticity at room temperature. Systematic investigations have been performed to reveal the effect of alloy addition on the alteration of the microstructure and the properties of nano-lamellar phases. Even though, in some cases, alloy addition stabilizes micrometer-sized proeutectic bcc/fcc solid solution phase(s) with dendritic morphology, but the residual melt solidifies into a binary nanoeutectic comprised of alternating soft bcc/fcc phase together with hard intermetallic phase. Furthermore, electron microscopic studies of differently deformed specimens and strain rate jump test have been performed to reveal the role of eutectic lamellae on the strain rate sensitivity and to explore the origin of plasticity in nanoeutectic composites. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
40. Structural, electrical and magnetic behavior in high-temperature sintered ZnMnO.
- Author
-
Das, J., Mishra, D., Srinivasu, V., Sahu, D., and Roul, B.
- Abstract
Nanocrystalline Mn-doped ZnO of compositions ZnMnO (0 ≤ x ≤ 0.08) has been synthesised by chemical route for uniform substitution of Mn in Zn site and then sintered at 1300 °C. Systematic investigations show the effect of Mn doping level and the sintering temperature on the structural, electrical and magnetic properties of ZnO. The average size of the nanocrystalline particles is in the order of 30-50 nm, whereas the grain sizes of the sintered specimen are of the order of few microns. Substitution of Mn in ZnO has been confirmed from the X-ray diffraction peak shift. A few peaks related to secondary phases of MnO have been observed in the X-ray diffraction patterns of the doped samples. ZnO and Mn-doped ZnO show Ohmic behavior and increased resistivity value with the increasing concentration of Mn. Effect of Mn concentration in ZnO has also been reflected in the dielectric constant and dielectric loss values. All the sintered samples show paramagnetic behavior even though the presence of MnO with oxygen vacancies is evident in X-ray photoelectron spectroscopic study. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
41. Expression of serum miR-200a, miR-200b, and miR-200c as candidate biomarkers in epithelial ovarian cancer and their association with clinicopathological features.
- Author
-
Zuberi, M., Mir, R., Das, J., Ahmad, I., Javid, J., Yadav, P., Masroor, M., Ahmad, S., Ray, P., and Saxena, A.
- Abstract
Background: MicroRNAs (miRs) have been implicated in the etiology of various human cancers. The aim of this study was to investigate the association of the expression of three members-miR 200a, miR 200b, and miR 200c belonging to the miR-200 family with clinicopathological characteristics and their impact on the progression of epithelial ovarian cancer (EOC). Materials and methods: Total RNA from serum was isolated by Trizol method, polyadenylated, and reverse transcribed into cDNA. Expression levels of miR-200a, miR-200b, and miR-200c were detected by using miRNA qRT-PCR. We measured miR expression in 70 serum samples of EOC patients with matched controls using U6 snRNA as a reference. Levels of miR expression was compared with distinct clinicopathological features. Results: Expression of miR-200a was found to be greater than six-fold ( p = 0.01), miR-200b and miR-200c greater than three-fold ( p = 0.01) in comparison with matched normal controls. Association of miRNA expression with clinicopathological factors and progression was statistically evaluated. The expression levels of miR-200a and miR-200c were found to be significantly associated with disease progression ( p = 0.04 and p < 0.001, respectively). miR-200a overexpression was found be associated with tumor histology and stage. Patients with lymph node metastasis showed significant elevation of miR-200c ( p = 0.006). The AUC in ROC curve also indicated that serum levels of miR-200a and miR-200c might be worthwhile as a diagnostic tool in the near future. Conclusion: Our findings suggest that miR-200a, miR-200b, and miR-200c overexpressions are associated with the aggressive tumor progression and be recognized as reliable markers to predict the prognosis and survival in EOC patients. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
42. Redox signalling to nuclear regulatory proteins by reactive oxygen species contributes to oestrogen-induced growth of breast cancer cells.
- Author
-
Okoh, V O, Garba, N A, Penney, R B, Das, J, Deoraj, A, Singh, K P, Sarkar, S, Felty, Q, Yoo, C, Jackson, R M, and Roy, D
- Subjects
BREAST cancer risk factors ,CELLULAR signal transduction ,CANCER cell growth ,PHYSIOLOGICAL effects of estrogen ,PHOSPHATASES ,IMMUNOPRECIPITATION - Abstract
Background:17β-Oestradiol (E2)-induced reactive oxygen species (ROS) have been implicated in regulating the growth of breast cancer cells. However, the underlying mechanism of this is not clear. Here we show how ROS through a novel redox signalling pathway involving nuclear respiratory factor-1 (NRF-1) and p27 contribute to E2-induced growth of MCF-7 breast cancer cells.Methods:Chromatin immunoprecipitation, qPCR, mass spectrometry, redox western blot, colony formation, cell proliferation, ROS assay, and immunofluorescence microscopy were used to study the role of NRF-1.Results:The major novel finding of this study is the demonstration of oxidative modification of phosphatases PTEN and CDC25A by E2-generated ROS along with the subsequent activation of AKT and ERK pathways that culminated in the activation of NRF-1 leading to the upregulation of cell cycle genes. 17β-Oestradiol-induced ROS by influencing nuclear proteins p27 and Jab1 also contributed to the growth of MCF-7 cells.Conclusions:Taken together, our results present evidence in the support of E2-induced ROS-mediated AKT signalling leading to the activation of NRF-1-regulated cell cycle genes as well as the impairment of p27 activity, which is presumably necessary for the growth of MCF-7 cells. These observations are important because they provide a new paradigm by which oestrogen may contribute to the growth of breast cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
43. Trigonometric characterization of some plane curves.
- Author
-
Barua, B. and Das, J.
- Subjects
PLANE curves ,TRIGONOMETRY ,CARTESIAN coordinates ,ANGLES ,POLAR coordinates (Mathematics) - Abstract
There is a way to describe a family of plane curves different from that using Cartesian or polar co-ordinates. This is a trigonometric equation involving two angles. In this article, we highlight the fact that trigonometric equations are convenient to describe certain one-parameter families of plane curves. In some cases, the trigonometric form makes it easier to characterize the family than if one were to use the equivalent Cartesian or polar representations. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
44. Tuffisitic Kimberlite from Eastern Dharwar Craton, Undraldoddi Area, Raichur District, Karnataka, India.
- Author
-
Das, J. N., Korakoppa, M. M., Fareeduddin, Shivanna, S., Srivastava, J. K., and Gera, N. L.
- Published
- 2013
- Full Text
- View/download PDF
45. Inaugural Function of the Geological Society of India Regional Centre — Odisha.
- Author
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Khaoash, Somnath and Das, J. N.
- Subjects
- *
EARTH system science - Published
- 2022
- Full Text
- View/download PDF
46. The degradation of p53 and its major E3 ligase Mdm2 is differentially dependent on the proteasomal ubiquitin receptor S5a.
- Author
-
Sparks, A., Dayal, S., Das, J., Robertson, P., Menendez, S., and Saville, M. K.
- Subjects
P53 antioncogene ,UBIQUITINATION ,PROTEASOMES ,UBIQUITIN ligases ,ENZYME denaturation ,GENE expression - Abstract
p53 and its major E3 ligase Mdm2 are both ubiquitinated and targeted to the proteasome for degradation. Despite the importance of this in regulating the p53 pathway, little is known about the mechanisms of proteasomal recognition of ubiquitinated p53 and Mdm2. In this study, we show that knockdown of the proteasomal ubiquitin receptor S5a/PSMD4/Rpn10 inhibits p53 protein degradation and results in the accumulation of ubiquitinated p53. Overexpression of a dominant-negative deletion of S5a lacking its ubiquitin-interacting motifs (UIM)s, but which can be incorporated into the proteasome, also causes the stabilization of p53. Furthermore, small-interferring RNA (siRNA) rescue experiments confirm that the UIMs of S5a are required for the maintenance of low p53 levels. These observations indicate that S5a participates in the recognition of ubiquitinated p53 by the proteasome. In contrast, targeting S5a has no effect on the rate of degradation of Mdm2, indicating that proteasomal recognition of Mdm2 can be mediated by an S5a-independent pathway. S5a knockdown results in an increase in the transcriptional activity of p53. The selective stabilization of p53 and not Mdm2 provides a mechanism for p53 activation. Depletion of S5a causes a p53-dependent decrease in cell proliferation, demonstrating that p53 can have a dominant role in the response to targeting S5a. This study provides evidence for alternative pathways of proteasomal recognition of p53 and Mdm2. Differences in recognition by the proteasome could provide a means to modulate the relative stability of p53 and Mdm2 in response to cellular signals. In addition, they could be exploited for p53-activating therapies. This work shows that the degradation of proteins by the proteasome can be selectively dependent on S5a in human cells, and that this selectivity can extend to an E3 ubiquitin ligase and its substrate. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
47. Antimicrobial activity of metal based nanoparticles against microbes associated with diseases in aquaculture.
- Author
-
Swain, P., Nayak, S., Sasmal, A., Behera, T., Barik, S., Swain, S., Mishra, S., Sen, A., Das, J., and Jayasankar, P.
- Subjects
ANTIBIOTICS ,THERAPEUTICS ,MICROORGANISMS ,NANOPARTICLES ,ANTI-infective agents ,CYANOBACTERIA - Abstract
The emergence of diseases and mortalities in aquaculture and development of antibiotics resistance in aquatic microbes, has renewed a great interest towards alternative methods of prevention and control of diseases. Nanoparticles have enormous potential in controlling human and animal pathogens and have scope of application in aquaculture. The present investigation was carried out to find out suitable nanoparticles having antimicrobial effect against aquatic microbes. Different commercial as well as laboratory synthesized metal and metal oxide nanoparticles were screened for their antimicrobial activities against a wide range of bacterial and fungal agents including certain freshwater cyanobacteria. Among different nanoparticles, synthesized copper oxide (CuO), zinc oxide (ZnO), silver (Ag) and silver doped titanium dioxide (Ag-TiO) showed broad spectrum antibacterial activity. On the contrary, nanoparticles like Zn and ZnO showed antifungal activity against fungi like Penicillium and Mucor species. Since CuO, ZnO and Ag nanoparticles showed higher antimicrobial activity, they may be explored for aquaculture use. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
48. Comparison of Cognitive Process Measures Across Three Cultural Samples: Some Surprises.
- Author
-
Das, J., Sarnath, Jagruti, Nakayama, Takeshi, and Janzen, Troy
- Abstract
Investigations of cognitive processes of children in three different countries (India, Canada, & Japan) are reported extending the validity of measures of Planning, Attention, Simultaneous, and Successive (PASS) processing. Results of average and low achieving school children in India on Cognitive Assessment System (CAS) comprising the four PASS scales showed that low achievers are low on all processing measures. Among Canadian Native children, Simultaneous processing was stronger and Successive was poorer. Children's performance on Japanese standardization of CAS revealed the same 4 PASS factor structures as in the American CAS. However, in each case, there was a surprise: Indian children scored higher than American norm for Successive scale; only those Canadian Native children who were poor in reading performed poorly in Successive scale, and among the Japanese, Simultaneous processing was higher. Results are discussed in terms of the influence of cultural context and school instructions. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
49. Webinars and E-Classes by Institution of Geoscientists, Odisha.
- Author
-
Sar, R. N., Mohanty, M., and Das, J. N.
- Subjects
EARTH scientists ,MINERALS ,GEMS & precious stones ,IRON ores ,EARTH sciences ,PLATINUM - Published
- 2021
- Full Text
- View/download PDF
50. Measurement of statistical evidence on an absolute scale following thermodynamic principles.
- Author
-
Vieland, V., Das, J., Hodge, S., and Seok, S.
- Subjects
- *
THERMODYNAMICS , *MEDICAL research , *INFERENTIAL statistics , *INFORMATION theory , *STATISTICS , *PHYSICS , *QUANTITATIVE research - Abstract
Statistical analysis is used throughout biomedical research and elsewhere to assess strength of evidence. We have previously argued that typical outcome statistics (including p values and maximum likelihood ratios) have poor measure-theoretic properties: they can erroneously indicate decreasing evidence as data supporting an hypothesis accumulate; and they are not amenable to calibration, necessary for meaningful comparison of evidence across different study designs, data types, and levels of analysis. We have also previously proposed that thermodynamic theory, which allowed for the first time derivation of an absolute measurement scale for temperature (T), could be used to derive an absolute scale for evidence (E). Here we present a novel thermodynamically based framework in which measurement of E on an absolute scale, for which 'one degree' always means the same thing, becomes possible for the first time. The new framework invites us to think about statistical analyses in terms of the flow of (evidential) information, placing this work in the context of a growing literature on connections among physics, information theory, and statistics. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
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