Production of Hepatotoxin by the Cyanobacterium Scytonema sp . Strain BT 23

(Kumar),(Ashok),(D . P . Singh),(M . B . Tyagi),(Arvind Kumar),(E . G . Prasuna),(J . K . Thakur) 한국미생물생명공학회 2000 Journal of microbiology and biotechnology Vol.10 No.3

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Structural, magnetic and optical properties of diluted magnetic semiconductor (DMS) phase of Ni modified CuO nanoparticles

Kumar Arvind,Kumar Manish,Chandra Sati Prakash,Srivastava Manish Kumar,Ghosh Surajit,Kumar Shiv 한국물리학회 2021 Current Applied Physics Vol.32 No.-

Control on the size of copper oxide (CuO) in the nano range is a highly motivating approach to study its multifunctional nature. The present investigation reports a sol-gel derived Ni doped CuO nanoparticles (Cu1- xNixO). Rietveld refinement of the XRD spectra confirms the formation of single monoclinic phase of Cu1-xNixO nanoparticles having crystallite size within the range of 19–21 nm. Raman spectra show the presence of characteristics Raman active modes and vibrational bands in the Cu1-xNixO samples that corroborate the monoclinic phase of the samples as revealed by refinement of XRD data. The estimated band gap of pure CuO is found to be ~1.43 eV, which decreases with the increase of dopant concentration into CuO matrix. This result is in line with estimated crystallite size. Magnetization curves confirm the weak ferromagnetic nature of Cu1-xNixO nanoparticles which reveal the DMS phase. This weak magnetic nature may be induced in the samples due to the exchange interaction between the localized magnetic d-spins of Ni ions and carriers (holes or electrons) from the valence band of pristine CuO lattice. Replacement of Cu+2 by Ni+2 ions into the host CuO lattice induces the magnetization. The quantified value of squareness ratio (S < 0.5) confirms the inter-grain magnetic interactions in the Cu1-xNixO nanoparticles which is also the reason of weak induced magnetization.

Study of electronic structure and dielectric properties of Gd-doped cobalt nanoferrites

Kumar Arvind,Gora Mahendra Kumar,Kumar Sanjay,Choudhary Banwari Lal,Singhal Rishi Kumar,Dolia Satya Narain 한국물리학회 2022 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.81 No.9

The current article explores the dielectric and electronic properties of cobalt ferrite nanoparticles with Gd substitution in a series CoGdxFe2-xO4 (0≤x≤0.1, in step x=0.02) synthesized by the sol–gel self-combustion way. All the samples were studied with Fourier transform infra-red (FTIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and impedance (dielectric) analyzer. One absorption band (υ1) was observed in FTIR measurements, which is the characteristic feature of spinel nanoferrites in fcc type structure. The presence of active Raman modes in Raman spectra at room temperature demonstrated single phase formation of cobalt nanoferrites with metallic–metallic and metallic–oxygen bonding vibrations in the tetrahedral and octahedral sites. XPS data analysis confrmed phase purity and revealed incorporation of Gd ion in the spinel fcc lattice. The valence states of Fe, Co & Gd atoms in all these nanoparticles are found as Fe3+, Co2+, & Gd3+. The dielectric constant and dielectric loss are measured in a broad frequency range of 100 Hz to 120 MHz. The dielectric constant reduces with a rise in Gd concentration and frequency. This study reveals that electronic and dielectric properties could be efectively tuned by varying concentrations of gadolinium in cobalt ferrite nanoparticles.

Stage specific feeding attributes and mobilization of nutrients in Mexican beetle, Zygogramma bicolorata Pallister on Parthenium hysterophorus L.

Patel Priya,Singh Shailesh,Patel Arvind Kumar,Kumar Bhupendra,Singh Arvind Kumar,Kumar Dinesh 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

Parthenium hysterophorus L. (Asteraceae) is a toxic weed of agricultural farms, pastures and wastelands with a pan-tropical distribution. The weed causes a reduction in crop production of agricultural fields and severe health problems in humans. The Mexican beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) is among the most promising candidates for the weed biocontrol. However, no previous study has evaluated assimilation of nutrients in this beetle. In the present study, feeding attributes and assimilation of nutrients by larvae of Z. bicolorata were assessed on the weed. Results revealed that the first larval instars of Z. bicolorata exhibited lowest consumption rates, and accumulated minimum concentrations of glucose, proteins and triglycerides in their body. They showed compensatory feeding, and displayed highest food utilization efficiencies and developmental rates. In contrast, the fourth larval instars exhibited higher food consumption rates and conversion efficiencies, but displayed lowest developmental rates. Accumulation of food reserves was also recorded maximum for the fourth larval instars. Overall, the findings may aid current mass-rearing efforts for Z. bicolorata in laboratories, but field trials are still needed to strengthen the present findings.

Implementation of Fuzzy Technique Based on LabVIEW for Control Gas System Using USB 6009

Arvind Kumar Parwal,Gaurav Parwal,Alok Sharma,Mohammad Arif Khan 보안공학연구지원센터 2013 International Journal of Control and Automation Vol.6 No.3

Baccaurea ramiflora Lour.: a comprehensive review from traditional usage to pharmacological evidence

Arvind Kumar Goyal,Middha Sushil Kumar,Talambedu Usha 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.2

Baccaurea ramiflora Lour. syn. Baccaurea sapida (Roxb.) Muell. Arg. widely known as Burmese grape is native to Southeast Asia. Its leaves, fruits, stem, bark, seeds forms an ingredient in many herbal prescriptions which have been used to treat jaundice, constipation, indigestion, cellulitis, as antidote for sanke venome, antiphlogistic and anodyne against rheumatoid arthritis etc. In the recent years, this plant has been largely explored on scientific grounds to identify the chemical constituents and pharmacological activities. The present review work is an effort to revisit the scientific works done to evaluate the scope for bioprospection of B. ramiflora. Based on the study designed, a number of research papers were reviewed, but only about 35 articles having information on B. ramiflora were evaluated in detail. In total, thirty compounds have been isolated and characterised so far from different parts of this evergreen tree, which accounts for its myriad medicinal value including analgesic, anthelmintic, antioxidant, anti-diarrheal, anti-inflammatory, cytotoxic, haemolytic, hypoglycemic, hypolipidemic, insecticidal, neuropharmacological, thrombocytic, anti-fungal and antimicrobial activities. This compilation of assorted information underpins the basic perceptive of B. ramiflora and opens up new horizon for further phytochemical evaluation, safety efficacy, and clinical trials.

Prediction of UCS and STS of Kaolin clay stabilized with supplementary cementitious material using ANN and MLR

Kumar, Arvind,Rupali, S. Techno-Press 2020 Advances in computational design Vol.5 No.2

The present study focuses on the application of artificial neural network (ANN) and Multiple linear Regression (MLR) analysis for developing a model to predict the unconfined compressive strength (UCS) and split tensile strength (STS) of the fiber reinforced clay stabilized with grass ash, fly ash and lime. Unconfined compressive strength and Split tensile strength are the nonlinear functions and becomes difficult for developing a predicting model. Artificial neural networks are the efficient tools for predicting models possessing non linearity and are used in the present study along with regression analysis for predicting both UCS and STS. The data required for the model was obtained by systematic experiments performed on only Kaolin clay, clay mixed with varying percentages of fly ash, grass ash, polypropylene fibers and lime as between 10-20%, 1-4%, 0-1.5% and 0-8% respectively. Further, the optimum values of the various stabilizing materials were determined from the experiments. The effect of stabilization is observed by performing compaction tests, split tensile tests and unconfined compression tests. ANN models are trained using the inputs and targets obtained from the experiments. Performance of ANN and Regression analysis is checked with statistical error of correlation coefficient (R) and both the methods predict the UCS and STS values quite well; but it is observed that ANN can predict both the values of UCS as well as STS simultaneously whereas MLR predicts the values separately. It is also observed that only STS values can be predicted efficiently by MLR.

Isolation of a Pseudomonas aeruginosa Strain Capable of Degrading Acrylamide

( Kumar Arvind,Ashok Kumar ) 한국미생물생명공학회 1998 Journal of microbiology and biotechnology Vol.8 No.4

Reference genes for expression studies in different developmental stages of Oryctes rhinoceros, the coconut rhinoceros beetle

Arvind Kumar,Antony Ginny,Rajesh M.K.,Josephrajkumar A.,Grace Tony 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.2

Oryctes rhinoceros L. (Coleoptera: Scarabaeidae), the coconut rhinoceros beetle (CRB), is a primary pest of co conut in South and Southeast Asia and the Pacific Islands. The beetle has the potential to severely affect the economies of local communities, many of whom are marginal and small farmers who rely on coconut as the main source of livelihood. Reverse transcription-quantitative real-time PCR (qRT-PCR) based targeted gene expression analysis has emerged as a powerful tool due to its sensitivity and reproducibility. However, calculating the relative expression of target genes requires normalization with reference genes across specific experimental conditions. To identify suitable reference gene(s) possessing stability, we selected six prospective genes (viz., NADH, ACTIN, EF1A, RPL3, SDHA, and ARF6) and evaluated them for their potential use as reference gene(s) across different developmental stages of O. rhinoceros. A comprehensive approach based on five statistical models viz., GeNorm, BestKeeper, NormFinder, RefFinder and the ΔCt value, was utilized, and based on the obtained stability values of candidate genes, a consensus ranking was generated. The expression levels of NADH, EF1A and RPL3 were observed to be the most stable across the developmental stages with significant statistical reliability. Further, this study identified NADH/EF1A as the most reliable reference gene combination which could provide robust normalization of RT-qPCR data in gene expression studies in O. rhinoceros. This is the first report iden tifying the suitable reference genes for normalizing gene expression in O. rhinoceros across different develop mental stages, facilitating future elucidation of gene expressions in this species.

Effect of geometrical parameters on rebound of impacting droplets on leaky superhydrophobic meshes

Kumar, Arvind,Tripathy, Abinash,Nam, Youngsuk,Lee, Choongyeop,Sen, Prosenjit The Royal Society of Chemistry 2018 Soft Matter Vol.14 No.9

<P>When a droplet impacts a superhydrophobic sieve, a part of the droplet penetrates through it when the dynamic pressure (<I>ρU</I><SUP>2</SUP>) of the impinging droplet exceeds the breakthrough pressure (<I>γΓ</I>/<I>A</I>). At higher impact velocities, the ejected-jet breaks and separates from the main droplet. The remaining part of the droplet bounces off the surface showing different modes (normal bouncing as a vertically elongated drop or pancake bouncing). In this work, we have studied the effect of different geometrical parameters of superhydrophobic copper meshes on different modes of droplet rebound. We observe three different effects in our study. Firstly, we observe pancake like bouncing, which is attributed to the capillary energy of the rebounding interface formed after the breaking of the ejected-jet. Secondly, we observe leakage of the droplet volume and kinetic energy due to the breaking of the ejected-jet, which leads to reduction in the contact times. Finally, we observe that for flexible meshes, the transition to pancake type bouncing is induced at lower Weber numbers. Flexibility also leads to a reduction in the volume loss from the ejected-jet. This study will be helpful in the design of superhydrophobic meshes for use under impact scenarios.</P>