Metal complexes of gliclazide: Preparation,spectroscopic and thermal characterization. Biological potential study of sulphonylurea gliclazide on the house fly,Musca domestica (Diptera – Muscidae)

Metal complexes of gliclazide (GLZ; HL) drug are prepared and characterized based on elemental analyses, IR, diffused reflectance, magnetic moment, molar conductance and thermal analyses (TG and DTG) technique. From the elemental analyses data, the complexes are proposed to have the general formulae [M(HL)Cl₃(H₂O)]·3H₂O (M = Cr(III) and Fe(III)), [M(HL)Cl₂(H₂O)₂]·yH₂O (M = Co(III), Ni(II) and Cu(II), y = 0–2) and [M(HL)Cl₂]·yH₂O (M = Mn(II) and Zn(II), y = 0–1). The molar conductance data reveal that all the metal chelates are non-electrolytes. IR spectra show that GLZ is coordinated to the metal ions in a neutral bidentate manner with ON donor sites of the amide-O and sulphonamide-OH. From the magnetic and solid reflectance spectra, it is found that the geometrical structures of these complexes are octahedral (Cr(III), Fe(III), Co(II), Ni(II) and Cu(II)) and tetrahedral (Mn(II) and Zn(II)). The thermal behaviour of these chelates is studied using thermogravimetric analysis (TG and DTG) techniques. The results obtained show that the hydrated complexes lose water molecules of hydration followed immediately by decomposition of the anions and ligand molecules in the successive unseparate steps. The activation thermodynamic parameters are calculated using Coats–Redfern method. The GLZ drug, in comparison to its metal complexes also is screened for their biological activity against house fly, Musca domestica (Diptera – Muscidae). Dose of 5 μg/insect of gliclazide is typically applied against 3 days-old larval instar of M. domestica. Survival of pupal and adult stages has been affected by the complexes of gliclazide more than larval instars. Morphogenic abnormalities of larvae, pupae and adults are studied. On the other hand, pupation and adult emergence program is deteriorated by the effect of different chemicals.     

Optimization approaches of aircraft flight path reducing noise: Comparison of modeling methods

An optimization model of flight paths is designed for minimizing aircraft noise at reception points around airports. It is stated as a nonconvex and nonlinear control problem governed by ordinary differential equations using a jet noise model. The vertical plan and the space cases have been solved using two approaches, one direct and one indirect. The objective was initially to apply these two methods, then to carry out comparisons, and finally to retain the method which would be applied for the general case including engine and airframe sources. Results showed that the direct method is adapted for solving the problem and can be implemented with moderate computing times. It is sufficient to analyze the constrained flight path optimization of commercial aircraft reducing noise levels. The three-segment approach procedure has been obtained as an optimized flight path which can substantially reduce noise levels. This modified approach procedure has been examined and could benefit both airlines and communities.     

Search for Down-Type Fourth Generation Quarks with the ATLAS Detector in Events with One Lepton and Hadronically Decaying W Bosons

This Letter presents a search for pair production of heavy down-type quarks decaying via b^{'}→Wt in the lepton+jets channel, as b^{'}b[over ˉ]^{'}→W^{-}tW^{+}t[over ˉ]→bb[over ˉ]W^{+}W^{-}W^{+}W^{-}→l^{±}νbb[over ˉ]qq[over ˉ]qq[over ˉ]qq[over ˉ]. In addition to requiring exactly one lepton, large missing transverse momentum, and at least six jets, the invariant mass of nearby jet pairs is used to identify high transverse momentum W bosons. In data corresponding to an integrated luminosity of 1.04 fb^{-1} from pp collisions at sqrt[s]=7 TeV recorded with the ATLAS detector, a heavy down-type quark with mass less than 480?GeV can be excluded at the 95% confidence level.     

Signing and Verifying Encrypted Medical Images Using Double Random Phase Encryption

Digital Signature using Self-Image signing is introduced in this paper. This technique is used to verify the integrity and originality of images transmitted over insecure channels. In order to protect the user’s medical images from changing or modifying, the images must be signed. The proposed approach uses the Discrete Wavelet Transform to subdivide a picture into four bands and the Discrete Cosine Transform DCT is used to embed a mark from each sub-band to another sub-band of DWT according to a determined algorithm. To increase the security, the marked image is then encrypted using Double Random Phase Encryption before transmission over the communication channel. By verifying the presence of the mark, the authority of the sender is verified at the receiver. Authorized users’ scores should, in theory, always be higher than illegal users’ scores. If this is the case, a single threshold might be used to distinguish between authorized and unauthorized users by separating the two sets of scores. The results are compared to those obtained using an approach that does not employ DWT.     

A facile one‐pot regioselective synthesis of [1,2,4]triazolo[4,3‐a]5(1H)‐pyrimidinones via tandem Japp–Klingemann,Smiles rearrangement,and cyclization reactions

Coupling of active [(4‐oxo‐6‐phenyl‐3H‐pyrimidin‐2‐yl)thio]methine compounds ( 3 ) with diazotized anilines in the presence of base gave [1,2,4]triazolo[4,3‐a]pyrimidines ( 7 ). The latter products were also obtained by reactions of hydrazonoyl chlorides ( 10 ) with either 6‐phenyl‐2‐thiouracil ( 1 ) or the 2‐methylthio derivative 9 . The mechanisms and the regiochemistry of the reactions studied are discussed. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:136–140, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10008     

Green magnetic snail shell hydroxyapatite sorbent for reliable solid-phase extraction of pesticides from water samples

To address sustainability issues, the green synthesis of nanomaterials has recently received considerable attention. This article addresses a novel and cost-effective adsorbent for the extraction of eight phenyl-N-methylcarbamate insecticides from water samples. We first synthesized a magnetite/hydroxyapatite nanocomposite using snail shell powder via an environmental friendly approach. The morphology and physicochemical properties of magnetic hydroxyapatite were characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Magnetic extraction parameters were optimized using a Doehlert matrix. Under optimum conditions, the magnetic extraction coupled with a LC–MS method shows good linearity with R² ≥ 0.9982, suitable intra- and interday precision, and limits of detection and quantification in the range of 0.052–0.093 μg/L and 0.11–0.31 μg/L, respectively. Satisfactory relative recoveries of all carbamates were achieved from fortified water samples in the range of 93.89–101.01%.     

Control of Quantum-Memory Induced by Generated Thermal XYZ-Heisenberg Entanglement: y-Component DM Interaction

This study explores the thermal quantum-memory-assisted entropic uncertainty relation (QM-EUR) and entanglement in a general two-qubit XYZ-Heisenberg spin chain model in the presence of the Dzyaloshinskii–Moriya (DM) interaction. The characterization of y-component DM and spin–spin interactions are particularly focused. It is found that the DM and spin–spin interaction strengths highly regulate the flow behavior and the initial final levels of QM-EUR and entanglement. In comparison, the spin–spin interaction strength in the z-direction remains useful in both ferromagnetic and anti-ferromagnetic regimes for entropic uncertainty suppression and entanglement generation. Additionally, the negative and the positive $y\mathrm{-}$directed DM values can usefully turn classical states into resourceful quantum states. The dynamics of thermal QM-EUR and entanglement-of-formation have symmetric behaviors only with respect to y-component DM and z-component spin–spin interaction. Finally, different critical points of temperature, $y\mathrm{-}$component DM as well as spin–spin interaction are encountered, which should be opted to preserve quantum correlations and degrade uncertainty.     

Endangered species,real options,and forest management

We use a real option approach to determine optimally when a social planner has to stop or resume logging in situations where an endangered species relies on forest habitat for its survival, and that habitat evolves stochasticly. The model incorporates economic, ecological and social features, and is calibrated to generate an optimal forest management rule that balances the benefits from commercial forest exploitation with the risks of extinction facing the endangered species. For the reasonable parameters used in our application to the Rangifer tarandus caribou, an endangered species in Central Labrador (Canada), the policy of banning logging temporarily is quite attractive as it does not require long banning periods while it drastically reduces the extinction risk and increases forest value. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)