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1

Cancer therapeutics strategy using nano-carrier mediated natural drugs

Shaw S., Singh P., Mishra R., Singh R., Nayak R., Bose S.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 114, nr 1

32--41

EN

Purpose: Nucleolin is a multifactorial protein, having a significant role in chromatin remodelling, mRNA stability, ribosome biogenesis, stemness, angiogenesis, etc., thus, it is potential therapeutic target in cancer. The purpose of this paper is to study porous silicon (pSi) nanocarrier-based natural drug delivery system targeting dysregulated nucleolin expression for cancer therapeutics. Design/methodology/approach: Quercetin was loaded in pre-synthesized and characterized pSi nanoparticles, and release kinetics was studied. The study compared the inhibitory concentration (IC50) of quercetin, synthetic drug doxorubicin, and quercetin-loaded pSi nanoparticles. Further, mRNA expression of a target gene, nucleolin, was tested with a quercetin treated breast cancer cell line (MCF-7). Findings: Quercetin-loaded pSi nanoparticles followed first-order release kinetics. IC50 was determined at concentrations of 312 nM, 160 μM, and 50 μM against doxorubicin, quercetin, and quercetin-loaded pSi nanoparticles, respectively. The results further indicated 16-fold downregulation of nucleolin mRNA expression after 48h of quercetin treatment of exponentially growing MCF-7 cells. Research limitations/implications: Whether pSi nanoparticle loaded quercetin can significantly downregulate nucleolin protein expression and its impact on apoptosis, cell proliferation, and angiogenic pathways need further investigation. Practical implications: The practical application of the proposed nanocarrier-based drug delivery system potentially lays out a path for developing targeted therapy against nucleolin-dysregulated cancer using natural products to minimize the side effects of conventional chemotherapeutic drugs. Originality/value: Inhibition of nucleolin and nucleolin regulated pathways using natural compounds and its targeted delivery with nanocarrier is not yet done.

2

Reach of an inclined cantilever with a tip load

Singh P., Goss V. G. A.

Archives of Mechanics

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2019

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Vol. 71, nr 6

595--614

EN

We investigate the problem of determining the reach of an inclined cantilever for a given point load suspended from its tip. Two situations are considered. Firstly, we find the maximum reach of the cantilever by varying its angle of inclination. Secondly, we find the reach of the cantilever subject to the condition that its tip is at some specified height, above or below, the level of the clamped end. In the second case, the reach of the cantilever is maximised by shortening its physical length whilst keeping the physical load and physical height of load deployment constant. All of our solutions representing various reaches of an inclined cantilever for a given point load suspended from its tip are shown to be stable to the snap-back instability.

3

Protocols for Wireless Sensor Networks: A Survey

Kochhar A., Kaur P., Singh P., Sharma S.

Journal of Telecommunications and Information Technology

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2018

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nr 1

77--87

EN

This paper presents a survey on the MAC and network layer of Wireless Sensor Networks. Performance requirements of the MAC layer are explored. MAC layer protocols for battery-powered networks and energy harvesting-based networks are discussed and compared. A detailed discussion on design constraints and classification of routing protocols is presented. Several routing protocols are compared in terms of such parameters as: energy consumption, scalability, network lifetime and mobility. Problems that require future research are presented. The cross-layer approach for WSNs is also surveyed.

4

A hybrid gene selection method for microarray recognition

Shukla A. K., Singh P., Vardhan M.

Biocybernetics and Biomedical Engineering

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2018

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Vol. 38, no. 4

975--991

EN

DNA microarray data is expected to be a great help in the development of efficient diagnosis and tumor classification. However, due to the small number of instances compared to a large number of genes, many of the computational learning methods encounter difficulties to select the low subgroups. In order to select significant genes from the high dimensional data for tumor classification, nowadays, several researchers are exploring microarray data using various gene selection methods. However, there is no agreement between existing gene selection techniques that produce the relevant gene subsets by which it improves the classification accuracy. This motivates us to invent a new hybrid gene selection method which helps to eliminate the misleading genes and classify a disease correctly in less computational time. The proposed method composes of two-stage, in the first stage, EGS method using multi-layer approach and f-score approach is applied to filter the noisy and redundant genes from the dataset. In the second stage, adaptive genetic algorithm (AGA) work as a wrapper to identify significant genes subsets from the reduced datasets produced by EGS that can contribute to detect cancer or tumor. AGA algorithm uses the support vector machine (SVM) and Naïve Bayes (NB) classifier as a fitness function to select the highly discriminating genes and to maximize the classification accuracy. The experimental results show that the proposed framework provides additional support to a significant reduction of cardinality and outperforms the state-of-art gene selection methods regarding accuracy and an optimal number of genes.

5

Asymptotic analysis of the clamped-pinned elastica

Singh P., Goss V. G. A.

Archives of Mechanics

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2018

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Vol. 70, nr 4

317--336

EN

Asymptotic solutions for the clamped-pinned elastica when the displacement of the pinned end is small (immediately after buckling) and when it approaches its limiting displacement (when the force in the rod tends to infinity) are presented. Simple leading order relationships describing the force as a function of the pinned end’s displacement are derived. Those approximate the force-displacement behaviour of the clamped-pinned elastica for small and limiting end displacements. All our results are valid for the clamped-pinned elastica in any mode.

6

Color image encryption using affine transform in fractional Hartley domain

Singh P., Yadav A. K., Singh K.

Optica Applicata

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2017

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Vol. 47, nr 3

421--433

EN

A novel scheme for color image encryption using the fractional Hartley and affine transforms is proposed. An input color image is first decomposed in its RGB (red, green and blue) components. Each component is bonded with a random phase mask and then subjected to a fractional Hartley transform followed by affine transform. Thereafter, a second random phase mask is applied to each component before the final transformation by fractional Hartley transform resulting in a component-wise encrypted image. Finally, all three components are combined to give a single channel encrypted image. The scheme is validated with numerical simulations performed on a color image of size 256 × 256 × 3 pixels using MATLAB 7.14. The use of affine transform along with fractional Hartley transform adds to the security. The scheme is evaluated for its sensitivity to the parameters of the fractional Hartley and affine transforms. On analysing the plots of correlation coefficient and mean-squared-error, the scheme is found to be highly sensitive to the encryption parameters. Also, it is evaluated for its robustness against the usual noise and occlusion attacks. The proposed scheme is secure and robust owing to multiplicity of encryption parameters introduced through the type of transforms used.

7

Relay-assisted WDM-FSO System: A Better Solution for Communication under Rain and Haze Weather Conditions

Dayal N., Singh P., Kaur P.

Journal of Telecommunications and Information Technology

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2017

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nr 4

54--59

EN

Among various conventional wireless communication systems, Free Space Optics (FSO) may be distinguished as well, which provides a good level security, high data rates, an enormous bandwidth and negligible susceptibility to electromagnetic interference. The main problem arises with unfavorable weather conditions, which affect the system’s parameters and require an aversion to other paths. The weather conditions discussed are rain and haze. Elimination of their adverse effects is essential for establishing a better communication system. The routing path is a major issue, as its decreased parameters lead to the diversion of the transmitted signal or to its total loss. In this article, increased system path length and proﬁciency levels are demonstrated by using relays, which are assisted by Wavelength Division Multiplexing (WDM).

8

Mitigation of Scintillation Effects in WDM FSO System using Multibeam Technique

Grover M., Singh P., Kaur P.

Journal of Telecommunications and Information Technology

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2017

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nr 2

69--74

EN

Free Space Optical communication (FSO) has engrossed a large section of researchers in recent times due to its wide bandwidth, effortless deployment and immune links making it appropriate for communication purposes. This wireless optical technique requires clear and non-turbulent atmospheric conditions for efficient transmission. In this paper, authors aim at reducing the effect of turbulent atmospheric conditions like scintillation effect on FSO. Multibeam technique, which uses spatially diverse transmitters for transmission, has been used for increasing the achievable link distance of the FSO system. Parameters like quality factor and bit error rate have been used to check the received signal quality.

9

Fuzzy Logic Based Adaptive Resonance Theory-1 Approach for Offline Signature Verification

Jain C., Singh P., Rana A.

Image Processing & Communications

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2017

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Vol. 22, no. 3

23--30

EN

This paper presents the use fuzzy logic with adaptive resonance theory-1 in signature verification. Fuzzy model is capable of stable learning of recognition categories in response to arbitrary sequences of binary input pattern. The work was carried out on two famous available signature corpuses i.e. MCYT (Online Spanish signatures database) and GPDS (Grupo de Procesado Digital de la se?al). Local binary patterns (LBP) and Gray Level Co-occurrence Matrices (GLCM) features were calculated for robust offline signature verification system. Training and verification was done using fuzzy adaptive resonance theory-1(FART-1). The system is trained and verified for different datasets to increase the accuracy of the classifier. The results thus obtained are robust than other existing techniques. The FAR and FRR for the system is 0.74% and 0.83% respectively.

10

Denoising of ECG signal by non-local estimation of approximation coefficients in DWT

Singh P., Pradhan G., Shahnawazuddin S.

Biocybernetics and Biomedical Engineering

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2017

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Vol. 37, no. 3

599--610

EN

This paper presents an ECG denoising technique using merits of discrete wavelet transform (DWT) and non-local means (NLM) estimation. The NLM-based approach is quite effective in removing low frequency noises but it suffers from the issue of under-averaging in the high-frequency QRS-complex region. In addition to that, the computational cost of NLM estimation is also high. The DWT, on the other hand, is effective in removing high-frequency noise but needs larger decomposition levels in order to denoise the low-frequency components. Thresholding lower-frequency components in the DWT domain often results in a loss of critical information. To overcome these drawbacks, in the proposed method, two-level DWT decomposition is first performed in order to decompose the noisy ECG signal into low- and high-frequency approximation and detail coefficients, respectively, at each level. The high frequency noise is removed by thresholding the detail coefficients at both the levels. The noise in the lower-frequency region is then removed by performing NLM estimation of Level 2 approximation coefficient. The Level 2 approximation coefficients actually represent the low-frequency envelope of the ECG. Thus, the proposed technique effectively combines the power of both NLM and DWT. At the same time, the computational cost of whole process is not more than the earlier existing techniques since NLM estimation is performed only on Level 2 approximation coefficients instead of the complete ECG signal. The proposed method is found to be superior to the existing state-of-the-art techniques when tested on the MIT-BIH arrhythmia database.

11

Ranking of generalized fuzzy numbers with generalized fuzzy simplex algorithm

Kumar A., Singh P.

Journal of Mathematics and Applications

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2011

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Vol. 34

53--73

EN

Ranking of fuzzy numbers play an important role in decision making problems. Fuzzy numbers must be ranked before an action is taken by a decision maker. Jain (Decision-making in the presence of fuzzy variables, IEEE Transactions on Systems, Man and Cybernetics 6 (1976) 698-703) proposed the concept of ranking function for comparing normal fuzzy numbers. Chen (Operations on fuzzy numbers with function principal, Tamkang Journal of Management Science 6 (1985) 13-25) pointed out that in many cases it is not to possible to restrict the membership function to the normal form and proposed the concept of generalized fuzzy numbers. Chen and Chen (Fuzzy risk analysis based on the ranking generalized fuzzy numbers with different heights and different spreads, Expert Systems with Applications 36 (2009) 6833-6842) pointed out the shortcomings of the existing methods for the ranking of generalized fuzzy numbers and proposed a new method. In this paper the shortcomings of the Chen and Chen method are pointed out and a new method is proposed for the ranking of generalized fuzzy numbers. Also using the proposed ranking method, a generalized simplex algorithm is proposed for solving a special type of fuzzy linear programming (FLP) problems. To illustrate the proposed algorithm a numerical example is solved and the advantages of the proposed algorithm are discussed. Since the proposed algorithm is a direct extension of classical algorithm so it is very easy to understand and apply the proposed algorithm to find the optimal solution of FLP problems occurring in the real life situations.

12

Finite element stress analysis of laminated composite plates

Singh P., Singh R.

International Journal of Applied Mechanics and Engineering

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2011

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Vol. 16, no 3

851-867

EN

In the present work, a finite element program based on the classical lamination theory improved by Vinson's weighting function to include transverse shear effects is developed for the analysis of laminated composite plates. The finite element analysis of a clamped three layered square symmetric laminate under uniform loading is carried out using 8-noded isoparametric elements having five degrees of freedom at each node. The effect of plate side-to-thickness ratio (a/h) 4, 10, 50 and 100 100 is studied on the maximum values of the non-dimensionalized central deflection (w), non-dimensionalized stress resultants [...] and non-dimensionalized stresses [...]. The variation of non-dimensionalized normal stresses [...] and shear stresses [...] through the thickness (z/h) of the laminate at plate side-to-thickness ratio (a/h) 10 is also studied.

13

Chronology of Cauvery delta sediments from shallow subsurface cores using elevated-temperature post-IR IRSL dating of feldspar

Alappat L., Tsukamoto S., Singh P., Srikanth D., Ramesh R., Frechen M.

Geochronometria

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2010

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Vol. 37

37-47

EN

We present the results of luminescence dating of sediments from two cores from the Cauvery Delta in south-east India. Since all natural quartz OSL signals except one sample were in saturation, the elevated temperature post-IR IRSL protocol for K-feldspar was applied to establish a chronology. Internal dose rates of K-feldspar grains were calculated from the measured internal content of potassium, uranium, thorium and rubidium in the bulk of K-feldspar grains using solution ICP-OES and ICP-MS analysis. A substantial scatter in single-aliquot De values was observed which is most probably due to the effect of incomplete bleaching of fluvial sediments before burial. A minimum age model was applied to extract possible depositional ages. The study revealed that except an upper layer of Holocene sediments (< 5m), the majority of the upper ~50m of Cauvery delta sediments were deposited between marine isotope stage MIS-5 and MIS-10 or older. The feldspar luminescence ages also indicate the existence of a period of non deposition or erosion in the upper part of the cores.

14

On the magnetorotatory thermosolutal convection (MRTC) of the Veronis type in the presence of Soret effect

Mohan H., Kumar P., Singh P.

Studia Geotechnica et Mechanica

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2009

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Vol. 31, nr 2

51-63

EN

In the present paper, we mathematically prove that the Soret-driven thermosolutal convection of the Veronis type under the simultaneous effect of uniform vertical rotation and magnetic field cannot manifest itself as oscillatory motions of growing amplitude if the thermosolutal Rayleigh number Rs, the Lewis number ζ, the Prandtl number δ and the magnetic Prandtl number δ 1 satisfy the inequalities