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Green chemistry protocols with the reusability of the nano particle as catalyst in the synthesis of coumarins is described. The zinc oxide (ZnO) nanoparticles functions as highly effective catalyst for the reactions of various o-hydroxy benzaldehydes with 1,3-dicarbonyl compounds under microwave and thermal conditions to afford the corresponding coumarins in moderate to good yields. The catalyst is inexpensive, stable, can be easily recycled and reused for several cycles with consistent activity.

The antibacterial activity, in-silico DNA molecular docking, DNA binding and photo cleavage studies of newly synthesized pyrazole is described. Antibacterial potential of these compounds screened against a wide range of Gram-positive and Gram-negative bacteria showed significant zone of inhibition and MIC with standard drug ciproflaxin is investigated. Among all the orientation of binding, fourth orientation showed significant binding and revealed that the binding and docking energy of 4a was -8.62 and -8.66 and inhibition constant 7.46 X e -6 . The absorption spectra showed the dynamic interaction with CT DNA and as proficient DNA intercalator (Kb = 4.5×10 4 M -1 ). The viscosity measurements and thermal denaturation affords the positive results towards DNA intercalation in both the studies. The light induced DNA damage was pragmatic in the absence of various ‘‘inhibitors’’ shows in photo cleavage activities at 360 nm.

Aim: The main objective of this paper is to study the synthesis of functionalized iron oxide nanoparticle and its reactivity towards chromene synthesis Study design: Functionalized iron oxide nanoparticle study. Place and duration of study: Department of Studies and Research in Industrial Chemistry, School of Chemical Sciences, Kuvempu University, Shankaraghatta, between December 2009 and July 2010. Methodology: This paper describes synthesis of stable functionalized iron oxide nanoparticles through surface modification of magnetic iron oxide nanoparticles by amino pyridine. Iron oxide nanoparticles were synthesized by co-precipitation method and the surface modification process was achieved by treating the nanoparticles with (chloro propyl trimethoxy silane) CPTS and aminopyridine. The developed functionalized iron oxide nanoparticle was evaluated as the catalyst for synthesis of chromones under MW irradiation conditions. Results: The catalysts were magnetically recovered and reusable without significant loss of their catalytic efficiency. To receive morphological and structural information on the obtained functionalized nanoparticle, the samples were analyzed by X-ray diffraction (XRD) measurements, FTIR and scanning electron microscopy (SEM) imaging. All synthesized chromene derivatives were characterized using analytical techniques such as IR, H NMR, and mass spectroscopy. Also the identity of these compounds was easily established by comparison of their melting point with those of reported samples. Conclusion: In summary, we have developed a new magnetically recyclable and Research Article American Chemical Science Journal, 1(3): 97-108, 2011 98 efficient functionalized magnetic nano catalyst for the chromene synthesis. Magnetic nanoparticle catalyst achieves a simple separation of catalyst without filtration including high yield in product.

A new ligand dibenzo[h]quinolineno[1,3,7,9] tetraazacyclododecine-7,15 (14H, 16H)-dibenzene (L) and its Co(II)/Cu(II) metal complexes of type [MLX2] (Where (M = Co(II) (5), Cu(II) (6) and X = Cl) were synthesized and are well characterized by FT-IR, 1H-NMR, FAB mass elemental analysis, and electronic spectral data. The role of the cobalt/copper metals in photo-induced DNA cleavage reactions was explored by designing complex molecules having macrocyclic structure. Finally, we have shown that photocleavage of plasmid DNA is more efficiently enhanced when this macrocyclic ligand is irradiated in the presence of copper(II) than that of cobalt metal.

TiO2 nanosheets were synthesized from tetrabutyl titanate precursor via solvothermal treatment using Hydrofluoric acid as structure directing agent. Anatase phase nanosheets could be obtained by this method, imparting good photocatalytic activity. In order to enhance photocatalytic activity, silver doping of TiO2 nanosheets was done using photo-deposition method under ultra-violet light irradiation. These nanosheets were characterized using Transmission electron microscopy, X-ray diffraction and Energy-dispersive X-ray spectroscopy. Photocatalytic activity was estimated by means of congo red dye degradation studies under ultra-violet light irradiation. The silver doped TiO2 nanosheets showed enhanced photocatalytic activity.

Energy consumption in wireless communication systems is increasing tremendously, wherein most of the energy consumedis by the evolved NodeBs in LTE network. Nowadays the research trend is majorly focused on Green communication which aims at reducing the Energy consumed in a network. In this paper, a radio resource allocation algorithm that is meant to balance energy efficiency and throughput maximization is proposed. The proposed algorithm is used to allocate Resource Blocks (RBs) to users considering the data rate requirements of the users based on priority for LTE downlink while maintaining Quality of Service (QoS). In this way the scarce spectrum is effectively utilized and the energy efficiency (EE) is improved. The proposed algorithm is compared with conventional scheduling algorithms such as Round Robin (RR), Best CQI (Best CQI/BCQI) and is analyzed on the basis of throughput, fairness and Energy Consumption Ratio (ECR).

A new class of Cu(II) and Co(II) complexes of azo-containing Schiff base of the type [Cu(L1)2] and [Co(L1)2], where L1 = 4-[(E)-{2-hydroxy-3-[(E)-(4-bromophenyl)diazenyl]benzylidene}amino]benzoic acid have been synthesized and characterized. Extension of conjugation and the presence of free carboxylic acid group of the ligand L1 increased the wavelength of the complexes from visible region to the near IR region (620–850 nm). The Cu(II) and Co(II) complexes interacted with CT-DNA via intercalative mode with the respective Kb value of 3.2 × 104 M−1 and 2.9 × 104 M−1 and acted as proficient photocleavers of SC pUC19 DNA in UV-A light, forming 1O2 as the reactive oxygen species with the quantum yield of 0.38 and 0.36, respectively. Furthermore, the Cu(II) and Co(II) complexes showed photocytotoxicity toward two selected tumor cell lines MCF-7 and A549 by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) method, and the Cu(II) complex exhibits higher photocytotoxicity than Co(II) complex against each of the selected cell lines, this result is identical with their DNA binding ability order.

Iron oxide supported amino acid as recoverable catalyst is applied in Knoevenagel condensation leading to different substituted coumarin derivatives.

The DNA-binding and photonuclease activity of newly synthesized tetra-azamacrocyclic ligand L (C(32)H(32)N(8)O(4)) and its complexes of type [MLCl(2)] and [ML]Cl(2) (where M = Co(II), Fe(II) and Cu(II); L = N,N'-[3-(4-{5-[(2-amino-ethylamino)-methyl]-isoxazol-3yl}-phenyl)-isoxazol-5-yl methyl-ethane-1,2-diamine] are specified. An octahedral geometry has been proposed for Fe(II) and Co(II) complexes, while the Cu(II) complex has a square planar environment. The absorption spectral results indicate that the complexes bind with the base pairs of DNA, with an intrinsic binding constant K(b) of Fe(II), Co(II), and Cu(II) complexes found to be 3.2 × 10(4) M(-1), 5.3 × 10(4) M(-1), and 4.2 × 10(4) M(-1), respectively, in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2. The large enhancement in the relative viscosity of DNA on binding to the complexes supports the proposed DNA binding modes. The viscosity and thermal denaturation studies sustain the effective intercalation with DNA. The DNA photocleavage studies demonstrated that compounds exhibit significant photonuclease activity by a concentration dependent on singlet oxygen mediated mechanism.

Green chemistry protocols with the reusability of the nano particle as catalyst in the synthesis of coumarins is described. The zinc oxide (ZnO) nanoparticles functions as highly effective catalyst for the reactions of various o-hydroxy benzaldehydes with 1,3-dicarbonyl compounds under microwave and thermal conditions to afford the corresponding coumarins in moderate to good yields. The catalyst is inexpensive, stable, can be easily recycled and reused for several cycles with consistent activity.

A new series of N,N'-(benzene-1,3-diyldi-1,3,4-oxadiazole-5,2-diyl)bis{2-[(5-benzene-1,3-diyl-1,3,4-oxadiazol-2-yl)amino]acetamide}(macrocycle 1), N,N'-(benzene-1,3-diyldi-1,3,4-thiadiazole-5,2-diyl)bis{2-[(5-benzene-1,3-diyl-1,3,4-thiadiazol-2-yl)amino]acetamide} (macrocycle 2) and S,S'-[benzene-1,3-diylbis(4H-1,2,4-triazole-5,3-diyl)]bis{[(5-benzene-1,3-diyl-4H-1,2,4-triazol-3-yl)sulfanyl]ethanethioate}(macrocycle 3) was synthesized from isophthalic dihydrazide (4) through a multistep reaction sequence. All the synthesized compounds were screened for their inhibitory effect against four different bacterial strains: P. aeruginosa ATCC-20852, K. pneumoniae MTCC-618, S. aureus ATCC- 29737, S. typhi MTCC- 3214. The synthesized compounds showed a significant zone of inhibition and the results were comparable with that of the standard drug ciprofloxacin. The synthesized compounds were further studied for their possible in vitro antioxidant effects by DPPH scavenging, total antioxidant capacity, total reductive capacity and H(2) O(2) scavenging activity. The results indicated that the in vitro antioxidant activity for all the three molecules was efficient when compared to the standards. The DNA interaction behavior of macrocycles 1-3 with CT-DNA was investigated by the absorption spectra obtained (K(b) constant for 1 is 4.53 × 10(4) M(-1) , for 2 is 5.75 × 10(4) M(-1) and for 3 is 5.86 × 10(4) M(-1) ). Based on the results it can be interpreted that the reducing power effect of the newly synthesized compounds demonstrates a direct effect on DNA binding and hence inhibiting the bacterial growth through their action on DNA by inhibiting DNA replication or DNA transcription.

The prime aim of the current work is to develop and validate a novel, specific, sensitive, precise, rapid and faster isocratic elution, RP HPLC method for estimation of Divalproex in bulk and pharmaceutical dosage forms. Chromatographic separation was achieved on Agilent SB C18, (50 x 4.6 mm, 5μ) using an isocratic mode with mobile phase composed of Buffer and Acetonotrile are taken in 60: 40%v/v(PH 4) The flow rate was 1.0ml/min, temperature is maintained at 30°C and detection was made at 210 nm. The run time was 8 min. The developed method was validated according to the ICH guide lines and different analytical parameters such as linearity, precision, accuracy, specificity, limit of detection, limit of quantitation were determined. The linearity of calibration curve for each analyte is in concentration range of 25-150ppm. There exists good correlation between peak area and analyte concentration. Relative standard deviation values for Divaprolex is 1.24. LOD for drug is 2.3 and LOQ is 9.4. Hence the proposed method is highly sensitive, precise, accurate, robust and fast. The short retention time allows the analysis of large number of samples in short period of time and it is cost effective, so it can be successfully applied for routine analysis of active pharmaceutical ingredient and related impurities in bulk and pharmaceutical dosage forms.

This paper introduces Gabor wavelet grids localized within the region of importance (ROI) for a robust pattern recognition system that is capable of recognizing various image classes. The representation of the patterns is based on Gabor wavelet transforms. The features are extracted as a vector of values using an optimally chosen multiple frequency, multiple orientation 2D symmetrical Gabor wavelet grid that spans the region of importance (ROI). This technique of feature extraction is biologically motivated. The purpose of this study is to demonstrate that localized Gabor wavelet grids with a MLP classifier can be effectively used for recognition of various types of patterns. Recognition of close to 100% is demonstrated for some real world patterns like faces, currency notes, postage stamps and typed characters.

We present a system for recognizing human faces from a database consisting of multiple images per test subject, which spans the normal variations in a human face. The faces are represented based on a Gabor wavelet transform. The features are extracted as a vector of values using a carefully chosen symmetrical Gabor wavelet matrix. This feature extraction is biologically motivated and models systems based on human vision. The extracted features are fed into an artificial neural network, in dual phases. The training and testing phases of the neural network work on the features extracted by the same method. Excellent pattern-recognition-specific neural network like a multilayer perceptron with back propagation provides the necessary classification once the feature extraction is complete

Tele-communication and network industry are becoming extremely fascinated by the use of evolutionary smart sensor nodes in wireless sensor networks. This technology promises to overcome several challenges within WSNs needed for real time data protection via optimization technique: Genetic Algorithm. This paper reviewedthe use of Genetic Algorithms (GAs) to solve certain limitation of wireless sensor networks. It further presents major application areas of wireless sensors networks. Longerdistance gap between a sensor and destination in a sensor network can remarkably reduce the energy of sensors and can degrade the life of a network. GA can prolong the network lifetime by minimizing the total communication distance.