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Baruah B.K.,GIMT | Das B.,NEHU | Misra A.K.,Gauhati University
Journal of Chemical and Pharmaceutical Research | Year: 2014

Purification of drinking water using charcoal and river sand which is locally known as sand filter (SF) is very common in the rural areas of Assam, but limited research work has been reported on its scientific view points as well as on its modification. The main aim of this piece of work was to test the scientific importance of this indigenous rural water filtration technique and minimization of As problems in underground drinking water using different bamboo charcoals. Removal efficiency of four different bamboo charcoals viz. Bambusa balcooa, Bambusa nutans, Bambusa tulda and Bambusa padilla with river sands of variable grain size distribution was studied. At the pH range of 7.0-7.8 with As concentration in the range of 0.001-1.0 mg/L, removal efficiency of bamboo charcoals of B balcooa, B nutans, B tulda and B padilla were found 69.77, 64.09, 60.38 and 56.24% respectively. The extent of As removal by these bamboo charcoals were found highly pH dependent and also the removal rate decreased with the increase of the initial concentration of As beyond 1 mg/L at pH range 7.0-7.8. Study also revealed that contact time of raw water with modified filtration bed less than 1 hour and more than 2 hours was found to be less effective in As removal from ground water. © 2014, Journal of Chemical and Pharmaceutical Research. All rights reserved.


Mandal S.,GIMT | Saha G.,NEHU | Pal R.K.,University of Calcutta
Advances in Intelligent Systems and Computing | Year: 2016

Current progress in cellular biology and bioinformatics allow researchers to get a distinct picture of the complex biochemical processes those occur within a cell of the human body and remain as the cause for many diseases. Therefore, this technology opened up a new door to the researchers of computer science as well as to biologists to work together to investigate the causes of a disease. One of the greatest challenges of the post-genomic era is the investigation and inference of the regulatory interactions or dependencies between genes from the microarray data. Here, a new methodology has been devised for investigating the genetic interactions among genes from temporal gene expression data by combining the features of Neural Network and Cuckoo Search optimization. The developed technique has been applied on the real-world microarray dataset of Lung Adenocarcinoma for detection of genes which may be directly responsible for the cause of Lung Adenocarcinoma. © Springer India 2016.


Singh A.D.,NERIST | Subadar R.,NEHU
2015 International Symposium on Advanced Computing and Communication, ISACC 2015 | Year: 2015

For arbitrary branch Maximal Ratio Combining (MRC) diversity system over Two Wave Diffused Power (TWDP) fading channel, the channel capacity equations for adaptive transmission techniques are obtained. The capacity expressions are derived using the probability density function (PDF) expression of the output signal to noise ratio of MRC receiver. The effects of fading parameters K and Δ and diversity order, M, on the system capacity are evaluated for different adaptive transmission techniques. A comparison of the capacities for the various adaptive transmission schemes employed with MRC receiver over TWDP fading channel is also presented. © 2015 IEEE.


Singh A.D.,NERIST | Subadar R.,NEHU
AEU - International Journal of Electronics and Communications | Year: 2014

An expression for the probability distribution function (PDF) of the signal-to-noise ratio of a selection combining receiver in two-wave with diffuse power fading channel is derived. Using this PDF expression, the capacity for the different adaptive transmission techniques employing selection combining (SC) are obtained. The study presents the effects of the ratio of total dominant signal power to the scattered signal power on the system capacity. The change in the capacity of the system with the diversity order for a SC receiver in the fading channel is also presented. © 2013 Elsevier GmbH.


Subadar R.,NEHU | Singh A.D.,NERIST
AEU - International Journal of Electronics and Communications | Year: 2014

An expression of characteristic function of signal-to-noise ratio (SNR) for two waves with diffused power (TWDP) fading channel is derived. Using this expression, the expression for the probability density function (PDF) of the output SNR of maximal ratio combining (MRC) receiver is obtained. Expressions for the performance matrix of MRC receiver over TWDP fading channels are also deduced. PDF based approach is followed to derive expressions of outage probability and average symbol error rate for coherent and non-coherent m-ary modulation schemes. Effects of the number of branches M and the fading parameters K and Δ on the system performance are studied. The results obtained are verified by Monte Carlo simulation. © 2014 Elsevier GmbH.


Dinamani Singh A.,NERIST | Subadar R.,NEHU
Conference Proceeding - 2015 International Conference on Advances in Computer Engineering and Applications, ICACEA 2015 | Year: 2015

Performance expressions of Dual maximal ratio combining (MRC) receiver are derived for the receiver over non-identical two wave diffused power (TWDP) fading channels are derived. The probability density function (PDF) of the receiver output signal-to-noise ratio (SNR) is derived using characteristics function of the output SNR expression. The derived PDF expression is then used to obtained the various performance measures such as outage probability and average symbol error rate for both coherent and non-coherent modulation schemes. Studies on the effects of fading parameters (K and Δ) and modulation techniques on the performance of the diversity system are carried out. The numerically evaluated results are validated with either Monte Carlo simulation or published results. © 2015 IEEE.


Dinamani Singh A.,NERIST | Subadar R.,NEHU
Conference Proceeding - 2015 International Conference on Advances in Computer Engineering and Applications, ICACEA 2015 | Year: 2015

One of the significant indicators of the Quality of Service that can be achieved by a wireless communication system is the findings of capacity analysis. Hence, these results are of enormous significance to wireless communication system designers and engineers. Channel capacity expressions for dual branch Maximal Ratio Combining (MRC) diversity system with various adaptive transmission techniques over two wave diffuse power (TWDP) fading channels are derived. The probability density function (PDF) based method is applied for the derivation of these capacity expressions. The consequences of fading parameters K and Δ and diversity order M, on the capacity of MRC receiver with different adaptive transmission techniques have been examined. Finally, a comparison of the capacity of the receiver with various adaptive transmission schemes over TWDP fading channel is also presented. © 2015 IEEE.


Pfoze N.L.,NEHU | Kumar Y.,NEHU | Myrboh B.,NEHU | Bhagobaty R.K.,Microbiology Laboratory | Joshi S.R.,Microbiology Laboratory
Journal of Medicinal Plants Research | Year: 2011

The genus Mahonia belongs to one of the primitive groups of plant family Berberidaceae. A number of species from this genus are widely used in traditional and folk medicine systems in different parts of the world. Mahonia manipurensis crude alkaloid extract was obtained from the stem bark by extracting from 80% of methanol extract. In vitro antibacterial activity of the alkaloid extract was screened against five different pathogenic bacteria of clinical origin including two species of gram-negative and three species of gram-positive bacteria. Using agar well diffusion method, growth inhibition was observed in four of the five tested pathogens at two different concentrations (5 and 2.5 mg/ml). The result indicates that the alkaloid extract exhibited significant antibacterial activity. Similar antimicrobial activity was also reported from other species of this genus by previous workers. Minimum inhibitory concentration (MIC) was also determined using agar dilution method, following two-fold serial dilution and observed that the lowest value was exhibited by Bacillus cereus and Enterococcus faecalis each corresponding to 256 μg/ml concentration. ©2011 Academic Journals.


Subadar R.,NEHU | Mudoi R.,NEHU
2015 International Conference on Electronic Design, Computer Networks and Automated Verification, EDCAV 2015 | Year: 2015

In this paper, the outage probability and average bit error rate of a multiuser, multiple input multiple output (MIMO) systems has been incorporated with transmit antenna selection maximal ratio combining (TAS/MRC) over Rayleigh fading channels considering exponential correlation. Exponential correlation is observed when antennas are placed in a linear array in a receiver. A closed form analytical expressions for the outage probability and the ABER for binary modulations have been derived. Outage probability and ABER have been studied for various levels of correlation with different level of diversity order. Finally, obtained analytical expressions have been validated by Monte-Carlo simulation. © 2015 IEEE.


Kardong D.,Dibrugarh University | Verma A.K.,NEHU | Upadhyaya S.,Dibrugarh University | Borah D.,Dibrugarh University
International Journal of Pharmacy and Pharmaceutical Sciences | Year: 2013

Objective: The present investigation was an attempt to evaluate the phytochemical constituents, free radical scavenging activities and anticancer properties of the leaf extracts of wild Sarchoclamys pulcherrima Goud, a wild vegetable plant used by Mishing tribe of Assam. Materials and methods: The phytochemical analysis, free radical scavenging activities and cytotoxic properties of the plant was carried out in the ethanolic extract of leaves of Sarchoclamys pulcherrima Goud using DMSO as neutral solvent. Results: The study indicated the presence of most of the major phytochemicals viz. alkaloids, saponins, flavonoids, tannins etc. in the leaf extract of the plant. The free radical scavenging activity of the sample against DPPH and ABTS was recorded as 84.87% and 76.9% respectively and found comparable to that of the ascorbic acid (88.2% and 83% respectively). In vitro cytotoxicity assay indicated a maximum cell damaging activity (60% Viability) at the exposure concentration (100 μg/ml leaf extract) and least activity (90% Viability) at the exposure concentration (20 μg/ml leaf extract). Conclusion: The present investigation will help to evaluate the neutraceutical prospect of the plant species with scientific validation of a traditionally acclaimed medicinal food plant.

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