Wyniki wyszukiwania - Biblioteka Nauki

1

Relevance of immuno-contraceptive vaccines for population control

100%

Gupta S. K. , Koothan P. T.

Archivum Immunologiae et Therapiae Experimentalis

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1990

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tom 38

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nr 1-2

2

Catalyst regeneration techniques in naphtha reforming: Short review

100%

Gupta A. , Gupta S. K.

Chemical and Process Engineering

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2022

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tom Vol. 43, nr 2

101–-108

EN

Catalytic reforming is an important intermediate in the processing of crude (naphtha in particular) to obtain gasoline. The catalyst used in the process (platinum) is quite expensive and may negatively impact the business if not used judiciously. The aforesaid not only refers to the reduction in loss of the catalyst per unit of gasoline produced but also to the manufacturing of an environmentally friendlier product alongside which is the need of the planet and also a necessity to meet the increasingly strict government norms. In order to meet the above requirements, various refineries around the world use various well-known conventional methods which depend on the quality and quantity of crude manufactured by them. This paper focuses on highlighting recent advancements in methods of catalytic regeneration (CR) in the reforming unit of petroleum industries to produce high octane gasoline, without any major replacements in their existing setup. Research papers formulated by the application of methodologies involving non-linear models and real-time refinery data have only been considered to avoid any deviations/errors in practical applications. In-depth analysis of these papers has led to the origin of some ideas which have been included as suggestions and can be considered as subjects of further research. In all, the objective of the paper is to serve as a reference for researchers and engineers working on devising optimum methods to improve the regeneration of reforming catalysts.

3

Analysis of through transmission laser welding of Nylon6 by finite element simulation

100%

Gupta S. K. , Pal P. K.

Management and Production Engineering Review

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2018

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tom Vol. 9, No. 4

56--69

EN

Over the years laser welding has evolved as a fabrication process capable of overcoming the limitations of conventional joining methodologies. It facilitates the welding of diverse range of materials like metals, non-metals, polymers etc. Laser transmission welding is a technique employed for fabricating intricate shapes/contours in polymers with better precision compared to the other conventional processes. Nylon6, a synthetic semi-crystalline polymer is utilized as an engineering thermoplastic due to its high strength and temperature resistant properties. In the earlier researches, various welding techniques were employed for the fabrication of polymers and metals keeping the laser beam stagnant, and much emphasis was given only to temperature distribution along the different axes and limited attention was given to residual stress analysis. Therefore, in this research work, a three-dimensional time-dependent model using a moving laser beam is used to fabricate unreinforced Nylon6 specimens.

4

Relevance of the NR4A sub-family of nuclear orphan receptors in trophoblastic BeWo cell differentiation

100%

Malhotra S. S. , Gupta S. K.

Cellular and Molecular Biology Letters

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2017

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tom 22

5

Three new septate gregarines in Oryzaephilus mercator (F.), infesting different stored food items

80%

Ghose S. , Gupta S. K. , Haldar D. P.

Acta Protozoologica

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1987

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tom 26

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nr 3

6

Molecular characterization and phylogenetic relationships among microsporidian isolates infecting silkworm, Bombyx mori using small subunit rRNA (SSU-rRNA) gene sequence analysis

80%

Surendra Nath B. , Gupta S. K. , Bajpai A. K.

Acta Parasitologica

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2012

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tom 57

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nr 4

EN

The life cycle, spore morphology, pathogenicity, tissue specificity, mode of transmission and small subunit rRNA (SSU-rRNA) gene sequence analysis of the five new microsporidian isolates viz., NIWB-11bp, NIWB-12n, NIWB-13md, NIWB-14b and NIWB-15mb identified from the silkworm, Bombyx mori have been studied along with type species, NIK-1s_mys. The life cycle of the microsporidians identified exhibited the sequential developmental cycles that are similar to the general developmental cycle of the genus, Nosema. The spores showed considerable variations in their shape, length and width. The pathogenicity observed was dose-dependent and differed from each of the microsporidian isolates; the NIWB-15mb was found to be more virulent than other isolates. All of the microsporidians were found to infect most of the tissues examined and showed gonadal infection and transovarial transmission in the infected silkworms. SSU-rRNA sequence based phylogenetic tree placed NIWB-14b, NIWB-12n and NIWB-11bp in a separate branch along with other Nosema species and Nosema bombycis; while NIWB-15mb and NIWB-13md together formed another cluster along with other Nosema species. NIK-1s_mys revealed a signature sequence similar to standard type species, N. bombycis, indicating that NIK-1s_mys is similar to N. bombycis. Based on phylogenetic relationships, branch length information based on genetic distance and nucleotide differences, we conclude that the microsporidian isolates identified are distinctly different from the other known species and belonging to the genus, Nosema. This SSU-rRNA gene sequence analysis method is found to be more useful approach in detecting different and closely related microsporidians of this economically important domestic insect.

7

Mitochondrial DNA variation in the endangered fish Dawkinsia tambraparniei (Actinopterygii: Cypriniformes: Cyprinidae) from southern Western Ghats, India

80%

Kannan K. , Johnson J. A. , Kumar A. , Gupta S. K.

Acta Ichthyologica et Piscatoria

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2014

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tom 44

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nr 1

EN

Background. Dawkinsia tambraparniei (Silas, 1954) is confined to an area not exceeding 100 km2 within a single watershed—the Tamiraparani River, southern Western Ghats, India. Its populations have recently declined, earning the fish the endangered status. For effective conservation efforts it is important to determine the levels of genetic variation between different populations. Therefore we attempted to quantify the cytochrome b (Cyt b) and cytochrome c oxidase subunit I (COI) gene sequence similarity between different populations of D. tambraparniei, as well as to study the phylogenetic relation with the closely related species D. arulius and D. filamentosa. Materials and methods. Samples were collected from 9 locations and 10 individuals from each were preserved for DNA analysis. The partial sequence of Cyt b and COI genes were amplified and sequenced. The sequences were aligned by the visual method using BioEdit version 7.1.3.0 and edited using Sequencer 4.7. The Bayesian consensus tree was constructed using the Monte Carlo Markov Chain (MCMC) method by BEAST v1.7.5. Results. The partial sequences of Cyt b and COI from 90 specimens of Dawkinsia tambraparniei representing nine populations were examined. The Cyt b gene sequences showed that all populations belong to a single haplotype and no nucleotide variation was observed between populations. In the case of COI gene sequences, two haplotypes were revealed: an additional haplotype with a clear transition of C to T at the nucleotide 58 position was detected within the Thalayanai Stream population. The phylogenetic analysis of COI gene demonstrated that the pair wise genetic distance between D. tambraparniei and D. arulius was low (0.004 ± SE 0.003) when compared with the distance between D. tambraparniei and D. filamentosa (0.061 ± SE 0.012). Conclusion. The mitochondrial DNA analysis revealed very low diversity among investigated populations of D. tambraparniei for studied genes, with the only local population from the Thalayanai Stream demonstrating certain divergence. The phylogenetic analysis confirms the concept on the validity of D. tambraparniei as a separate species. This phylogenetic study also demonstrated that D. tambraparniei is closer to D. arulius, followed by D. filamentosa.

8

On the wave propagation in generalised thermoelastic media

80%

Sharma J. N. , Sharma P. K. , Gupta S. K.

International Journal of Applied Mechanics and Engineering

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2003

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tom Vol. 8, no 2

299-316

EN

In this paper, the analysis is based on the decoupled field equations of linear thermoelasticity without energy dissipation. These equations have been solved with the use of integral transforms. The dynamic behavior of an elastic half space due to (i) a line load and (ii) a mechanical load, acting on the boundary is also discussed. While the displacement in both of the cases is found to be continuous, the temperature, strain and stress are observed to be discontinuous at elastic and thermal wave fronts. The characteristic features of the underlying theory are analyzed in the light of these solutions and their counterparts in earlier works. The results obtained theoretically have been computed numerically and are represented graphically.

9

A Scheme for Template Security at Feature Fusion Level in Multimodal Biometric System

80%

Selwal A. , Gupta S. K. , Kumar S.

Advances in Science and Technology. Research Journal

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2016

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tom Vol. 10, nr 31

23--30

EN

Biometrics is the science of human recognition by means of their biological, chemical or behavioural traits. These systems are used in many real life applications simply from biometric based attendance system to providing security at a very sophisticated level. A biometric system deals with raw data captured using a sensor and feature template extracted from raw image. One of the challenges being faced by designers of these systems is to secure template data extracted from the biometric modalities of the user and protect the raw images. In order to minimize spoof attacks on biometric systems by unauthorised users one of the solutions is to use multi-biometric systems. Multi-modal biometric system works by using fusion technique to merge feature templates generated from different modalities of the human. In this work, a novel scheme is proposed to secure template during feature fusion level. The scheme is based on union operation of fuzzy relations of templates of modalities during fusion process of multimodal biometric systems. This approach serves dual purpose of feature fusion as well as transformation of templates into a single secured non invertible template. The proposed technique is irreversible, diverse and experimentally tested on a bimodal biometric system comprising of fingerprint and hand geometry. The given scheme results into significant improvement in the performance of the system with lower equal error rate and improvement in genuine acceptance rate.

10

Anomalous Variations of Ionosphere Associated with the Strong Earthquake at Pakistan-Iran Border at a Low Latitude Station Agra, India

80%

Pundhir D. , Singh B. , Singh O. P. , Gupta S. K.

Acta Geophysica

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2016

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tom Vol. 64, no. 3

796--809

EN

In this paper, we analyze the TEC data for April 2013 observed at Agra station, India (geogr. lat. 27.2° N, long. 78° E) to examine the effect of earthquake of magnitude M = 7.8 which occurred on 16 April 2013 at Pakistan–Iran border region. We process the TEC data using the σ statistical criterion to find out anomalous variation in TEC data. We also study the VLF propagation signal from NPM, Hawaii (21.42° N, 158° W), which is monitored at the same station (Agra station) in the light of this earthquake as well as solar flares. The nighttime fluctuation method is used to analyze the VLF data for the period of ±5 days from the day of earthquake (11-21 April 2013). The anomalous enhancements and depletions are found in TEC data on 1-9 days before the occurrence of event.

11

Thermally assisted OSL: a potent tool for improvement in minimum detectable dose and extension of dose range of Al2O3:C

61%

Soni A. , Mishra D. R. , Bhatt B. C. , Gupta S. K. , Rawat N. S. , Kulkarni M. S. , Sharma D. N.

Geochronometria

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2013

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tom Vol. 40, no. 4

258--265

EN

The influence of electron-phonon interaction on the shape of the optically stimulated lumi-nescence decay curve of Al2O3:C has been studied using thermally assisted optically stimulated lumi-nescence (TA-OSL). The minimum detectable dose (MDD) of a phosphor depends on the standard deviation of the background signal which affects the signal-to-noise ratio. The standard deviation of the background signal reduces at lower stimulation light intensity while the readout time increases. Further, measurement at higher temperature enhances the OSL signal with faster decay due to the temperature dependence of photo-ionization cross-section. To achieve the same decay constant and more signal, the temperature of measurement was raised. As a result of lowering the stimulation in-tensity at higher temperature (85°C) the overall MDD of α-Al2O3:C was found to improve by 1.8 times. For extension of dose linearity in higher range, deeper traps were studied by simultaneous ap-plication of CW-OSL and thermal stimulation up to 400°C, using a linear heating rate of 4K/s. By us-ing this method, two well defined peaks at 121°C and 232°C were observed. These TA-OSL peaks have been correlated with two deeper defects which can be thermally bleached at 650°C and 900°C respectively. These deeper defects are stable up to 500°C, so they can store absorbed dose infor-mation even if the sample is inadvertently exposed to light or heat. The dose vs. TA-OSL response from deep traps of α-Al2O3:C was found to be linear up to 10 kGy, thus extending its application for high dose dosimetry.

12

Intra and inter species genetic variability of transferrin receptor gene regions in Trypanosoma evansi isolates of different livestock and geographical regions of India

61%

Sarkhel S. P. , Gupta S. K. , Kaushik J. , Singh J. , Saini V. K. , Kumar S. , Kumar R.

Acta Parasitologica

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2017

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tom 62

|

nr 1

13

Genetic diversity among microsporidian isolates from the silkworm, Bombyx mori, as revealed by randomly amplified polymorphic DNA (RAPD) markers

61%

Surendra Nath B. , Hassan W. , Nageswara Rao S. , Vijaya Prakash N. B. , Gupta S. K. , Madana Mohanan N. , Bajpai A. K.

Acta Parasitologica

|

2011

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tom 56

|

nr 4

EN

Random amplification of polymorphic DNA polymerase chain reaction (RAPD-PCR) was carried out to assess the genetic diversity of five new microsporidian isolates viz., NIWB-11bp, NIWB-12n, NIWB-13md, NIWB-14b and NIWB-15mb identified from the silkworms. A type species, NIK-1s_mys was used as control for comparison. Differences in the spore shape, length and width were observed. Of the 30 decamer random primers tested, 22 primers gave repeatable RAPD profiles and yielded a total of 143 fragments, of which 78 were polymorphic (55%). The resulting data was used to derive genetic similarity values for constructing a dendrogram. The neighbour joining method based on Dice coefficients indicate a major cluster comprising NIK-1s_mys, NIWB-11bp and NIWB-12n, whereas NIWB-13md, NIWB-14b and NIWB-15mb appear to be different from each other as well from the major cluster mentioned above which includes the type species (NIK-1s_mys). Based on the reproducibility of RAPD profiles, we are able to identify these microsporidians as different isolates. The RAPD technique may be useful in detecting sources of infection of this economically important domestic insect.