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941.
** Email: msevkli{at}fatih.edu.tr*** Corresponding author. Email: mehmetaydin{at}acm.org, mehmet.aydin{at}beds.ac.uk Variable neighbourhood search (VNS) is one of the most recentmetaheuristics used for solving combinatorial optimization problemsin which a systematic change of neighbourhood with a local searchis carried out. However, as happens with other metaheuristics,it takes a long time to reach some useful solutions while solvingsome sort of hard combinatorial problems such as job shop scheduling(JSS). Parallelization is one of the most considerable policiesto overcome this matter. In this paper, firstly, a number ofVNS algorithms are examined for JSS problems and then four differentparallelization policies are taken into account to determineefficient parallelization for VNS algorithms. The experimentationreveals the performance of various VNS algorithms and the efficiencyof policies to follow in parallelization. In the end, the unilateral-ringtopology, a noncentral parallelization method, is found as themost efficient policy.  相似文献   
942.

Doxycycline capped gold nanoparticles (doxy-Au(0) NPs) were prepared in an aqueous medium. Particle size and shape were determined by Transmission electron microscopy which showed the monodispersed morphology. The Fourier transform infrared spectra were represented the interaction of doxycycline with surface of doxy-Au(0) NPs. X-ray powder diffraction study gave crystalline nature of the doxy-Au(0) NPs. These doxy-Au(0) NPs have an impact on the expression levels of TRP channel genes in the breast cancer line (SKBR3) and the breast epithelial cell line (CRL-4010). Additionally, the antimicrobial activities have been evaluated to be used for multiple applications. Our results showed that the expression levels of TRP genes can be changed following the treatment of AuNPs (50 and 100 µg/mL). Furthermore, the antimicrobial activies have achieved some significant results. Finally, it has been concluded that doxy-Au(0) NPs are novel and can be used as alternative nanomedicine and extendable for control of other reducible contaminants as well.

  相似文献   
943.
Cell and protein compatibility of parylene-C surfaces   总被引:2,自引:0,他引:2  
Parylene-C, which is traditionally used to coat implantable devices, has emerged as a promising material to generate miniaturized devices due to its unique mechanical properties and inertness. In this paper we compared the surface properties and cell and protein compatibility of parylene-C relative to other commonly used BioMEMS materials. We evaluated the surface hydrophobicity and roughness of parylene-C and compared these results to those of tissue culture-treated polystyrene, poly(dimethylsiloxane) (PDMS), and glass. We also treated parylene-C and PDMS with air plasma, and coated the surfaces with fibronectin to demonstrate that biochemical treatments modify the surface properties of parylene-C. Although plasma treatment caused both parylene-C and PDMS to become hydrophilic, only parylene-C substrates retained their hydrophilic properties over time. Furthermore, parylene-C substrates display a higher degree of nanoscale surface roughness (>20 nm) than the other substrates. We also examined the level of BSA and IgG protein adsorption on various surfaces and found that surface plasma treatment decreased the degree of protein adsorption on both PDMS and parylene-C substrates. After testing the degree of cell adhesion and spreading of two mammalian cell types, NIH-3T3 fibroblasts and AML-12 hepatocytes, we found that the adhesion of both cell types to surface-treated parylene-C variants were comparable to standard tissue culture substrates, such as polystyrene. Overall, these results indicate that parylene-C, along with its surface-treated variants, could potentially be a useful material for fabricating cell-based microdevices.  相似文献   
944.
New cyanation/phosphonate-phosphate rearrangement/C-acylation reactions of cyanophosphate anion with cyanoformate esters are described. Phase-transfer cocatalysts facilitate cyanide-catalyzed reactions between acyl phosphonates and cyanoformates to afford protected tertiary carbinol products in good to excellent yields (74-95%). Ethyl cyanoformate is used as a cyanide source and electrophile. The scope of the reaction was investigated by using a number of benzoyl and acyl phosphonates along with ethyl cyanoformate. Representative chemoselective reduction of the product 5a afforded ethyl 3-amino-2-hydroxy-2-phenylpropanoate (13) in good yield.  相似文献   
945.
5,11,17,23-Tetrakis(1,1-dimethylethyl)-25,26-dihydroxy-27,28-crown-4-calix[4]arene in the cone conformation was synthesized. This p-tert-butylcalix[4]arene-1,2-crown-4 compound was then anchored with Merrifield chloromethylated resin beads. The modified polymeric resin was characterized by 1H NMR, FT-IR and elemental analysis and used successfully for the separation and preconcentration of Cu(II), Cd(II), Co(II), Ni(II) and Zn(II) prior to their determination by FAAS. Effective extraction conditions were optimized in both batch and column methods. The resin exhibits good separating ability with maximum between pH 6.0-7.0 for Cu(II), pH 6.0 for Cd(II), pH 5.0 for Co(II), pH 4.0-4.5 for Ni(II), and pH 4.5 for Zn(II). The elution studies were carried out with 0.5 mol L−1 HCl for Cu(II), Co(II) and Co(II), 1.0 mol L−1 HCl for Cd(II) and Zn(II). The sorption capacity, preconcentration factor and distribution coefficient of each metal ion were determined. The detection limits were 1.10, 1.25, 1.83, 1.68 and 2.01 μg L−1 for Cu(II), Cd(II), Co(II), Ni(II) and Zn(II). The influence of several ions on the resin performance was also investigated. The validity of the proposed method was checked for these metal ions in NIST standard reference material 2709 (San Joaquin Soil) and 2711 (Montana Soil).  相似文献   
946.
Oscillatory properties of the half-linear second-order differential equation
(*)  相似文献   
947.
Practical HIV diagnostics are urgently needed in resource-limited settings. While HIV infection can be diagnosed using simple, rapid, lateral flow immunoassays, HIV disease staging and treatment monitoring require accurate counting of a particular white blood cell subset, the CD4(+) T lymphocyte. To address the limitations of current expensive, technically demanding and/or time-consuming approaches, we have developed a simple CD4 counting microfluidic device. This device uses cell affinity chromatography operated under differential shear flow to specifically isolate CD4(+) T lymphocytes with high efficiency directly from 10 microliters of unprocessed, unlabeled whole blood. CD4 counts are obtained under an optical microscope in a rapid, simple and label-free fashion. CD4 counts determined in our device matched measurements by conventional flow cytometry among HIV-positive subjects over a wide range of absolute CD4 counts (R(2) = 0.93). This CD4 counting microdevice can be used for simple, rapid and affordable CD4 counting in point-of-care and resource-limited settings.  相似文献   
948.
Direct electrochemical genosensor was developed for the detection of a probe sequence relative position in a PCR amplicon for the optimum detection of bacterial and microbiological diseases, in this study. The genosensor relies on a label-free electrochemical detection. The amino-linked inosine modified (guanine-free) coequal capture probes which were chosen from different parts of a PCR amplicon, immobilized on to disposable pencil graphite electrodes (PGE) by electrostatically and covalently. As a model case Hepatitis B virus (HBV) genome amplicon was used for the detection and specification. Hybridization was occurred after surface coverage with denatured amplicons. After hybridization, optimum probe sequence position was identified by using the differences between the responses of guanine oxidation signals. The results of this study might have a great convenience for the microbiological diseases detection applications such as DNA micro arrays.  相似文献   
949.
Water soluble PEG cored dendritic hexa-acid which comprises peripheral carboxylic acidic groups were prepared via nucleophilic substitution reactions. Novel anhydrous proton conducting electrolytes were prepared by incorporation of the heterocyclic protogenic solvent imidazole (Im) into PEG cored dendritic hexa acid, (PEG-HA), at several molar ratios of Im to-COOH units of PEG-HA. The complexation of PEG-HA and Im was illustrated by infrared spectroscopy (FT-IR). The materials are thermally stable up to 150 °C as evidenced by thermogravimetry analysis (TGA). Differential scanning calorimetry (DSC) results verified that the organic electrolytes are homogeneous and amorphous. The proton conductivities were characterized by means of AC impedance spectroscopy and a maximum conductivity of 1 × 10−3 S/cm was measured at 120 °C in the anhydrous state.   相似文献   
950.
A voltammetric method using a poly(1‐methylpyrrole) modified glassy carbon electrode was developed for the quantification of adrenaline. The modified electrode exhibited stable and sensitive current responses towards adrenaline. Compared with a bare GCE, the modified electrode exhibits a remarkable shift of the oxidation potentials of adrenaline in the cathodic direction and a drastic enhancement of the anodic current response. The separation between anodic and cathodic peak potentials (ΔEp) for adrenaline is 30 mV in 0.1 M phosphate buffer solution (PBS) at pH 4.0 at modified glassy carbon electrodes. The linear current response was obtained in the range of 7.5 × 10?7 to 2.0 × 10?4 M with a detection limit of 1.68 × 10?7 M for adrenaline by square wave voltammetry. The poly(1‐methypyrrole)/GCE was also effective to simultaneously determine adrenaline, ascorbic acid and uric acid in a mixture and resolved the overlapping anodic peaks of these three species into three well‐defined voltammetric peaks in cyclic voltammetry. The modified electrode has been successfully applied for the determination of adrenaline in pharmaceuticals. The proposed method showed excellent stability and reproducibility.  相似文献   
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