Showing papers by "Deen Dayal Upadhyay Gorakhpur University published in 2012"

Multiwavelength Variability of the Blazars Mrk 421 and 3C 454.3 in the High State

Abstract: We report the results of photometric observations of the blazars Mrk 421 and 3C 454.3 designed to search for intraday variability (IDV) and short-term variability (STV). Optical photometric observations were spread over 18 nights for Mrk 421 and 7 nights for 3C 454.3 during our observing run in 2009-2010 at the 1.04 m telescope at Aryabhatta Research Institute of Observational Sciences, India. Genuine IDV is found for the source 3C 454.3 but not for Mrk 421. Genuine STV is found for both sources. Mrk 421 was revealed by the Monitor of All-sky X-ray Image (MAXI) X-ray detector on the International Space Station to be in an exceptionally high flux state in 2010 January-February. We performed a correlation between the X-ray and optical bands to search for time delays and found a weak correlation with higher frequencies leading the lower frequencies by about 10 days. The blazar 3C 454.3 was found to be in a high flux state in 2009 November-December. We performed correlations in optical observations made at three telescopes, along with X-ray data from the MAXI camera and public release γ-ray data from the Fermi space telescope. We found strong correlations between the γ-ray and optical bands at a time lag of about four days, but the X-ray flux is not correlated with either. We briefly discuss the possible reasons for the time delays between these bands within the framework of existing models for X-ray and γ-ray emission mechanisms.

Optical flux and spectral variability of blazars

Abstract: We report the results of optical monitoring for a sample of 11 blazars including 10 BL Lacertae objects (BL Lacs) and one flat spectrum radio quasar (FSRQ). We have measured the multiband optical flux and colour variations in these blazars on intraday and short-term time-scales of months and have limited data for two more blazars. These photometric observations were made during 2009–2011, using six optical telescopes, four in Bulgaria, one in Greece and one in India. On short-term time-scales we found significant flux variations in nine of the sources and colour variations in three of them. Intraday variability was detected on six nights for two sources out of the 18 nights and four sources for which we collected such data. These new optical observations of these blazars plus data from our previous published papers (for three more blazars) were used to analyse their spectral flux distributions in the optical frequency range. Our full sample for this purpose includes six high-synchrotron-frequency-peaked BL Lacs (HSPs), three intermediate-synchrotron-frequency-peaked BL Lacs (ISPs) and six low-synchrotron-frequency-peaked BL Lacs (LSPs; including both BL Lacs and FSRQs). We also investigated the spectral slope variability and found that the average spectral slopes of LSPs show a good accordance with the synchrotron self-Compton loss dominated model. Our analysis supports previous studies that found that the spectra of the HSPs and FSRQs have significant additional emission components. The spectra of all these HSPs and LSPs get flatter when they become brighter, while for FSRQs the opposite appears to hold. This supports the hypothesis that there is a significant thermal contribution to the optical spectrum for FSRQs.

Biodiversity and Nutraceutical Quality of Some Indian Millets

Abstract: This study was designed to investigate the biodiversity and nutraceutical quality of some Indian millets. These crops are cold, drought and salinity tolerant and can be cultivated on marginal land also. Seeds were analyzed for dry matter, total N, protein N, protein and seed protein concentrate extractability. In addition, millets were categorized on the basis of poverty eradication/source of income, health management, food security and natural resource management. The study indicates that millets can potentially be developed as an active nutraceutical and industrial bioresources for the care of environment and sustainable health of the society and nature.

Quasi-simultaneous two-band optical variability of the blazars 1ES 1959+650 and 1ES 2344+514

Abstract: We report the results of quasi-simultaneous two-filter optical monitoring of two high-energy peaked blazars, 1ES 1959+650 and 1ES 2344+514, to search for microvariability and short-term variability (STV). We carried out optical photometric monitoring of these sources in an alternating sequence of B and R passbands, and have 24 and 19 nights of new data for these two sources, respectively. No genuine microvariability (intranight variability) was detected in either of these sources. This non-detection of intranight variations is in agreement with the conclusions of previous studies that high-energy peaked BL Lacs are intrinsically less variable than low-energy peaked BL Lacs in the optical bands. We also report the results of STV studies for these two sources between 2009 July and 2010 August. Genuine STV is found for the source 1ES 1959+650 but not for 1ES 2344+514. We briefly discuss possible reasons for the difference between the intranight variability behaviour of high- and low-energy peaked blazars.

Pharmacological effects of Sapindus mukorossi.

Abstract: Sapindus mukorossi is an extremely valuable medicinal plant, distributed in tropical and sub-tropical regions of Asia. The aim of present review is to form a short compilation of the phytochemical composition and pharmacological properties of this multipurpose tree. The main phytoconstituents isolated and identified from different parts of this plant are triterpenoidal saponins of oleanane, dammarane and tirucullane type. The structure and chemical names of all the types of triterpenoidal saponins reported in Sapindus mukorossi are included in this review. Many research studies have been conducted to prove the plant's potential as being spermicidal, contraceptive, hepatoprotective, emetic, anti-inflammatory and anti-protozoal. The present review highlights some of the salient pharmacological uses of Sapindus mukorossi.

In Silico Characterization of Alkaline Proteases from Different Species of Aspergillus

Abstract: A total of 49 protein sequences of alkaline proteases retrieved from GenBank representing different species of Aspergillus have been characterized for various physiochemical properties, homology search, multiple sequence alignment, motif, and super family search and phylogenetic tree construction. The sequence level homology was obtained among different groups of alkaline protease enzymes, viz alkaline serine protease, oryzin, calpain-like protease, serine protease, subtilisin-like alkaline proteases. Multiple sequence alignment of alkaline protease protein sequence of different Aspergillus species revealed a stretch of conserved region for amino acid residues from 69 to 110 and 130-204. The phylogenetic tree constructed indicated several Aspergillus species-specific clusters for alkaline proteases namely Aspergillus fumigatus, Aspergillus niger, Aspergillus oryzae, Aspergillus clavatus. The distributions of ten commonly observed motifs were analyzed among these proteases. Motif 1 with a signature amino acid sequence of 50 amino acids, i.e., ASFSNYGKVVDIFAPGQDILSCWIGSTTATNTISGTSMATPHIVGLSCYL, was uniformly observed in proteases protein sequences indicating its involvement with the structure and enzymatic function. Motif analysis of acidic proteases of Aspergillus and bacterial alkaline proteases has revealed different signature amino acid sequences. The superfamily search for these proteases revealed the presence of subtilases, serine-carboxyl proteinase, calpain large subunit, and thermolysin-like superfamilies with 45 representing the subtilases superfamily.

Biological utilities of Parthenium hysterophorus

Abstract: Parthenium hysterophorus L. (Asteraceae) is a serious weed of pastures, wasteland and agricultural fields in world. Various problems are posed by the weed to human health, agriculture, live stock production and biodiversity. It is used as folk remedy against various afflictions. The review discusses several prominent biological utilities of P. hysterophorus as it contains several important chemical constituents mainly histamine, saponin, glucosides and triterpene (sesquiterpene) and can be of use for the purpose of biocontrol of various pathogens , for its medicinal utility and even for the purpose of food.

Impact of Cypermethrin on Fingerlings of Common Edible Carp (Labeo rohita)

Abstract: Laboratory evaluations were made to assess the toxicological and biochemical effect of cypermethrin on fingerlings of common edible freshwater culture carp (Labeo rohita). There was a significant negative (𝑃 0.278 μg/L (12 h), > 0.240 μg/L (18 h) and >0.205 μg/L (24 h). Exposure to sublethal doses of cypermethrin for 24 h and 96 h exposure period caused significant (𝑃<0.05) time- and dose-dependent alterations in total protein, total free amino acids, nucleic acids, glycogen, pyruvate, and lactate level and in the activity of enzyme protease, alanine aminotransferase, aspartate aminotransferase, acid phosphatases, alkaline phosphatases, acetylcholinesterase, and cytochrome oxidase in liver and muscle tissues of fish. Thus, cypermethrin has potent piscicidal activity against fingerlings of fish Labeo rohita and adversely affects their behavioural patterns, shifting aerobic pathway of fish respiration towards anaerobic pathway and also inhibiting energy production by suppressing ATP synthesis.

The nature of the intra-night optical variability in blazars

Abstract: In this paper we present the results of a short-term optical monitoring program of 13 blazars. The objects were monitored mostly in the R band for a total of ∼160 h between 2006 and 2011. We study the nature of the short-term variations and show that most of them could be described as slow, smooth and (almost) linear changes of up to ∼0.1 mag h −1 , but that many objects show no short-term variations at all. In fact, we found only a ∼2 per cent chance of observing variability of more than 0.1 mag h −1 for the sample we observed. Hints of quasiperiodic oscillations at very low-amplitude levels are also found for some objects. We briefly discuss some of the possible mechanisms for generating the intra-night variability and the quasi-periodic oscillations.

Characterization of the molluscicidal activity of Bauhinia variegata and Mimusops elengi plant extracts against the fasciola vector lymnaea acuminata

Abstract: The molluscicidal activity of Bauhinia variegata leaf and Mimusops elengi bark was studied against vector snail Lymnaea acuminata. The toxicity of both plants was time and concentration-dependent. Among organic extracts, ethanol extracts of both plants were more toxic. Toxicity of B. variegata leaf ethanolic extract (96h LC50- 14.4 mg/L) was more pronounced than M. elengi bark ethanolic extract (96h LC50-15.0 mg/L). The 24h LC50 of column purified fraction of B. variegata and M. elengi bark were 20.3 mg/L and 18.3 mg/L, respectively. Saponin and quercetin were characterized and identified as active molluscicidal component. Co-migration of saponin (Rf 0.48) and quercetin (Rf 0.52) with column purified bark of M. elengi and leaf of B. variegata on thin layer chromatography demonstrate same Rf value i.e. 0.48 and 0.52, respectively. The present study clearly indicates the possibility of using M. elengi and/or B. variegata as potent molluscicide.

Fast ion conducting phosphate glasses and glass ceramic composites: Promising materials for solid state batteries

Abstract: Fast ion conducting (FIC) phosphate glasses and glass ceramic composites have gained considerable importance due to their potential applications in the fabrication of solid-state batteries and other electrochemical devices. We, therefore, present an overview on various types of FIC glasses and glass ceramic composites. Silver phosphate glasses doped with different weight percent of lithium chloride (1, 5, 10 and 15 wt.%) were synthesized by melt quenching technique. The Ag2O–P2O5–(15 wt.%) LiCl glass exhibited the maximum electrical conductivity (σ = 8.91 × 10− 5 S cm− 1 at room temperature and 4.16 × 10− 3 S cm− 1 at 200 °C). Using this glass as an amorphous host material, glass–ceramic composites of Ag2O–P2O5–(15 wt.%) LiCl:xAl2O3 (x = 5–50 wt.%) were prepared. The ionic transference number, electrical conductivity, ionic mobility and carrier ion concentration of the synthesized samples were measured. Ag2O–P2O5–(15 wt.%) LiCl:(25 wt.%) Al2O3 composite system exhibited the maximum σ value (σ = 3.32 × 10− 4 S cm− 1 at room temperature and 2.88 × 10− 2 S cm− 1 at 200 °C ). Solid‐state batteries using undoped Ag2O–P2O5 glass, Ag2O–P2O5–(15 wt.%) LiCl glass and glass ceramic composite containing 25 wt.% Al2O3 as electrolytes were fabricated. The open circuit voltage (OCV) values and discharge time of these cells were measured and compared. It is found that the glass ceramic composites show enhanced ionic conduction, better OCV value and discharge characteristics.

Analysis of genetic diversity in cowpea ( Vigna unguiculata L.Walp.) cultivars with random amplified polymorphic DNA markers

Abstract: The genetic diversity among ten Indian cultivars of cowpea was analyzed using 18 sets of RAPD markers. A total of 181 bands with an average of 15 bands per primer were obtained. Out of 181 bands, 148 showed polymorphism (81.7%). The variation in genetic diversity among these cultivars ranged from 0.1742 to 0.4054. Cluster analysis based on Jaccard’s similarity coefficient using UPGMA with high bootstrap values revealed two distinct clusters I and II comprised of two and seven cultivars, respectively. Cluster II was further differentiated into various subclusters. Cultivar IC-9883 was found to be unique based on its altogether distinct position in the dendrogram and two-dimensional space projections.

Response of Tribolium castaneum (Coleoptera: Tenebrionidae) and Sitophilus oryzae (Coleoptera: Curculionidae) to potential insecticide derived from essential oil of Mentha arvensis leaves

Abstract: The essential oil of Mentha arvensis L was extracted by water distillation method and the insecticidal properties of M arvensis were evaluated under laboratory conditions The oil showed repellency and toxicity against T castaneum (Coleoptera: Tenebrionidae) and S oryzae (Coleoptera: Curculionidae) The result revealed that this essential oil strongly repels T castaneum and S oryzae even at low concentration, but its repellency was more marked towards S oryzae The essential oil of M arvensis showed toxic effects against insect pests The toxicity of newly molted 4th instars larvae of T castaneum and 10-day-old-adults of T castaneum and S oryzae increased with concentration from 15 to 30 μL/100 μL and with exposure time 24 to 48 h The LC50 against the larvae of T castaneum was 18685 μL at 48 h exposure The LC50 against T castaneum and S oryzae adults were 22759 μL and 21788 μL at 48 h exposure, respectively

In vitro antibacterial activities of the essential oils of aromatic plants against Erwinia herbicola (Lohnis) and Pseudomonas putida (Kris Hamilton)

Abstract: This study was designed to examine the in vitro antibacterial acti- vities of the essential oils extracted from 53 aromatic plants of the Gorakhpur Division (UP, INDIA) for the control of two phytopathogenic bacteria, namely Erwinia herbicola and Pseudomonas putida, which cause several post-harvest diseases in fruits and vegetables. Out of the 53 oils screened, 8 oils, i.e., Che- nopodium ambrosioides, Citrus aurantium, Clausena pentaphylla, Hyptis sua- veolens, Lippia alba, Mentha arvensis, Ocimum sanctum and Vitex negundo, completely inhibited the growth of the test bacteria. Furthermore, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values of C. ambrosioides oil were lower for E. herbicola (0.25 and 2.0 µl ml -1 ) and P. putida (0.12 and 1.0 µl ml -1 ), respectively, than those of the other 7 oils, as well as than those of agromycin and streptomycin, the drugs used in the current study. Gas chromatography (GC) and GC-mass spectros- copy (GC-MS) analysis of the Chenopodium oil revealed the presence of 125 major and minor compounds, of which 14 compounds were recognized. The findings led to the conclusion that Chenopodium oil may be regarded as a safe antibacterial agent for the management of post-harvest diseases of fruits and vegetables.

A Laccase of Fomes durissimus MTCC-1173 and Its Role in the Conversion of Methylbenzene to Benzaldehyde

Abstract: A laccase has been purified from the liquid culture growth medium containing bagasse particles of Fomes durissimus. The method involved concentration of the culture filtrate by ultrafiltration and anion exchange chromatography on diethyl aminoethyl cellulose. The sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis both gave single protein band indicating that the enzyme preparation was pure. The molecular mass of the purified laccase determined from SDS-PAGE analysis was 75 kDa. Using 2,6-dimethoxyphenol as the substrate, the determined Km and kcat values of the laccase are 182 μM and 0.35 s−1, respectively, giving a kcat/Km value of 1.92 × 103 M−1 s−1. The pH and temperature optimum were 4.0 and 35 °C, respectively. The purified laccase has yellow colour and does not show absorption band around 610 nm found in blue laccases. Moreover, it transformed methylbenzene to benzaldehyde in the absence of mediator molecules, property exhibited by yellow laccases.

Prostaglandin E2 Increases Both Osteoblastic and Osteoclastic Activity in the Scales and Participates in Calcium Metabolism in Goldfish

Abstract: Using our original in vitro assay system with goldfish scales, we examined the direct effect of prostaglandin E₂ (PGE₂) on osteoclasts and osteoblasts in teleosts. In this assay system, we measured the activity of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) as respective indicators of each activity in osteoblasts and osteoclasts. ALP activity in scales significantly increased following treatment at high concentration of PGE₂(10⁻⁷ and 10⁻⁶ M) over 6 hrs of incubation. At 18 hrs of incubation, ALP activity also significantly increased in the PGE₂ (10⁻⁹ to 10⁻⁶ M)-treated scale. In the case of osteoclasts, TRAP activity tended to increase at 6 hrs of incubation, and then significantly increased at 18 hrs of incubation by PGE₂ (10(-7) to 10⁻⁶ M) treatment. At 18 hrs of incubation, the mRNA expression of osteoclastic markers (TRAP and cathepsin K) and receptor activator of the NF-κB ligand (RANKL), an activating factor of osteoclasts expressed in osteoblasts, increased in PGE₂ treated-scales. Thus, PGE₂ acts on osteoblasts, and then increases the osteoclastic activity in the scales of goldfish as it does in the bone of mammals. In an in vivo experiment, plasma calcium levels and scale TRAP and ALP activities in the PGE₂-injencted goldfish increased significantly. We conclude that, in teleosts, PGE₂ activates both osteoblasts and osteoclasts and participates in calcium metabolism.

On continuous Bessel wavelet transformation associated with the Hankel–Hausdorff operator

Abstract: The main objective of this paper is to study the continuous Bessel wavelet transformation and its inversion formula, and the Parseval relation using the theory of the Hankel convolution. A relation between the Bessel wavelet transformation and the Hankel–Hausdorff operator is established.

A comparison of crystallographic and DFT optimized geometries on two taxane diterpenoids and docking studies with phospholipase A2

Abstract: Structure optimization of two taxane diterpenoids I and II has been carried out using GAUSSIAN03 program with B3LYP/6-31G** basis set. The structures were fully optimized without any geometric constraints. Coordinates found in crystallographic study were used as input to the GAUSSIAN. The results show that the conformations of taxoid cores are almost same as were observed from crystallography, while the conformations of the substituents are slightly different. Thus, taxoid cores are robust enough to maintain their conformations in gaseous state while the conformations of substituents may vary depending upon the reaction condition. To understand the mode of binding, the docking studies of both compounds have been carried out with Russell’s viper phospholipase A2 (vPLA2) as target using induced fit docking. The docking results show that regarding the interactions and energy for indomethacin binding with vPLA2, compound I shows the best results.

Computational Studies on Nitro Derivatives of 1-Hydroxy-1,2,4-triazole

Abstract: Thermodynamic properties and energetics of the nitro derivatives of 1-hydroxy-1,2,4-triazole, viz. 1-hydroxy-3-nitro-1,2,4-triazole (A), 1-hydroxy-5-nitro-1,2,4-triazole (B), and 1-hydroxy-3,5-dinitro-1,2,4-triazole (C), are considered for a detailed computational study during the present investigation using a density functional theory B3LYP/6-311G(d,p) method as implemented in the Gaussian 03 suite of programs. Heats of formation and other thermodynamic properties for all of the compounds considered were determined. Studies revealed that these compounds possess the requisite properties for use as high-density energetic materials. Detonation velocity (D) and detonation pressure (P) of the title compounds were evaluated using the Kamlet-Jacobs method based on the crystal densities calculated at the DFT(B3LYP)/6-311G(d,p) level incorporating the electrostatic interaction. Calculation showed that these compounds yielded a detonation pressure and detonation velocity in the range of 27–35 GPa and ∼8 km/s, resp...

α-L-rhamnosidase from Aspergillus clavato-nanicus MTCC-9611 active at alkaline pH

Abstract: An a-L-rhamnosidase secreting fungal strain has been isolated and identified as Aspergillus clavato-nanicus MTCC-9611. The enzyme was purified to homogeneity from the culture filtrate of the fungus using concentration by ultrafiltration membrane and ion-exchange chromatography on CM-cellulose. The native PAGE analysis confirmed the homogeneity of the purified enzyme. The SDS-PAGE analysis of the purified enzyme revealed a single protein band corresponding to the molecular weight 82 kDa. The α-L-rhamnosidase activity of Aspergillus clavato-nanicus MTCC-9611 had optimum at pH 10.0 and 50°C. The Km values of the enzyme were 0.65 mM and 0.95 mM using p-nitrophenyl α-L-rhamnopyranoside and naringin as a substrates respectively. The enzyme transforms naringin to prunin at pH 10.0 and further hydrolysis of prunin to naringenin does not occur under these reaction conditions that makes α-L-rhamnosidase activity of Aspergillus clavato-nanicus MTCC-9611 promising enzyme to get prunin for pharmaceutical purposes.

Computational study on the thermal decomposition and isomerization of the CH3OCF2O• radical

Abstract: The geometries of the reactant, products, and transition states involved in the decomposition pathways of the CH3OCF2O• radical formed during the photooxidation of CH3OCHF2 (HFE-152a) have been optimized and characterized at the DFT-B3LYP level of theory using the 6–311G(d,p) basis set. Single-point energy calculations have been made at the G2M (CC,MP2) level of theory. Out of the four prominent decomposition channels considered, the β-C–O bond scission is found to be the dominant path involving a barrier height of 9.78 kcal mol–1 (1 cal = 4.184 J). The thermal rate constant for the above decomposition pathway is evaluated using canonical transition state theory (CTST) and was found to be 5.27 × 104 s–1 at 298 K and 1 atm (1 atm = 101.325 kPa).