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Array
Kinds of Array Terms modified by Array Selected AbstractsMONITORING BEHAVIOR WITH AN ARRAY OF SENSORSCOMPUTATIONAL INTELLIGENCE, Issue 4 2007Dorothy N. Monekosso The objective is to detect activities taking place in a home and to create a model of behavior for the occupant. A behavior is a pattern in the sequence of activities. An array of sensors captures the status of appliances. Models for the occupant's activities are built from the captured data using supervised and unsupervised learning techniques. The models of behavior are built using the hidden Markov model (HMM) technique. Predictive models can be used in a number of ways: to enhance user experience, to maximize resource usage efficiency, for safety and security. This work focuses on supporting independent living and enhancing quality of life of older persons. The ultimate goal is for the system to distinguish between normal and anomalous behavior. In this paper, we present the results of comparing supervised and unsupervised classification techniques applied to the problem of modeling activity for the purpose of modeling behavior in a home. [source] Data structures in Java for matrix computationsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2004Geir Gundersen Abstract In this paper we show how to utilize Java's native arrays for matrix computations. The disadvantages of Java arrays used as a 2D array for dense matrix computation are discussed and ways to improve the performance are examined. We show how to create efficient dynamic data structures for sparse matrix computations using Java's native arrays. This data structure is unique for Java and shown to be more dynamic and efficient than the traditional storage schemes for large sparse matrices. Numerical testing indicates that this new data structure, called Java Sparse Array, is competitive with the traditional Compressed Row Storage scheme on matrix computation routines. Java gives increased flexibility without losing efficiency. Compared with other object-oriented data structures Java Sparse Array is shown to have the same flexibility. Copyright © 2004 John Wiley & Sons, Ltd. [source] Heterogeneous Plasma-Producing Structures at Current Implosion of a Wire ArrayCONTRIBUTIONS TO PLASMA PHYSICS, Issue 8 2005E. V. Grabovsky Abstract Characteristic properties of the plasma production process have been considered for the case of megampere currents flowing through hollow cylindrical wire arrays of the Angara-5-1 facility. In 3-4 nanoseconds after voltage applying to the wire surfaces there appear a plasma layer. The system becomes heterogeneous, i.e. consisting of a kernel of metal wires and a plasma layer. In several nanoseconds the current flow goes from metal to plasma, which results in reducing the electric field strength along the wire. The Joule heat energy delivered to the metal before the moment of complete current trapping by plasma is insufficient for the whole mass transition to a hot plasma state. The X-ray radiography techniques made it possible to detect and study dense clusters of substance of ,1g/cm3 at a developed discharge stage. The radial expansion velocity of ,104 cm/s measured at the 70-th nanosecond after the current start allows treating the dense core at a late stage in the form of a submicron heterogeneous structure from its liquid and slightly ionized gas phase. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Simultaneous Quantification of Heavy Metals Using a Solid State Potentiometric Sensor ArrayELECTROANALYSIS, Issue 8 2009Jesús Gismera Abstract A potentiometric sensor array of four nonspecific electrodes with solid-state membranes is developed and tested for simultaneous analysis of copper(II), mercury(II), and silver(I) ions. The cross-sensitivity responses of the sensors for these ions are evaluated. The array potentiometric signals are processed by partial least-squares regression (PLS) and back propagation artificial neural networks (ANN) to determinate analyte concentrations. The ANN configuration is optimized and two different training algorithms of the ANN are also evaluated. Best results are obtained when the potentiometric sensors are activated and the data are processed using ANN and the gradient descent adaptive algorithm. The system is used to quantify these heavy metals in synthetic samples and in dental amalgams with successful results. [source] Simulation of Redox-Cycling Phenomena at Interdigitated Array (IDA) Electrodes: Amplification and SelectivityELECTROANALYSIS, Issue 5 2008M. Odijk Abstract We present Finite Element Method (FEM) simulations of interdigitated array (IDA) electrode geometries to study and verify redox selectivity and redox cycling amplification factor. The simulations provide an adequate explanation of an earlier found, but poorly understood, high amplification factor (65×) in a 1,,m-spaced IDA microdevice. Moreover, using the FEM calculations we present selectivity measurements with IDA electrodes in a mixture of two redox species, as for example dopamine and ferricyanide. We show that it is possible to electrochemically detect dopamine in presence of the stronger reductor ferricyanide, which is impossible with direct amperometric detection, with the use of IDA electrodes with proper polarization potential of the collector electrode. Using our simulations, we show that a theoretical selectivity of dopamine over ferricyanide of 11 can be achieved. [source] Preparation of Nanogapped Gold Nanoparticle Array for DNA DetectionELECTROANALYSIS, Issue 4 2008Shiho Tokonami Abstract A novel DNA detection technique using a gold nanoparticle array film electrode has been reported here. The gold nanoparticles molecularly linked with binder molecule (1,10-decanedithiol) were separated 1.3,nm from each other, and the DNA conductivity change from single to double strand was measured by monitoring a voltage drop across the particles, between which a probe of a 12-mer oligonucleotide was immobilized. In adding a complementary oligonucleotide on the nanoparticle film chip, an immediate decrease in the film resistance (ca. 1.4 ,) due to a hybridization event occurred in a reproducible manner with this simple setup. In the paper, we have an interest in the primary sensing properties; effect of the film resistance on the sensor response, dependence of the resistance change on the DNA concentration, and the performance of the system for DNA detection including single nucleotide polymorphisms were described. [source] Disposable Gold Electrode Array for Simultaneous Electrochemical StudiesELECTROANALYSIS, Issue 1 2008Graciela Priano Abstract An efficient and inexpensive eight gold electrode array has been manufactured by a combination of screen printing and gold electrodeposition techniques. Gold electrodeposition was performed in potentiostatic and galvanostatic conditions. Different treatments, involving temperature and polishing control, led to electrodes with different roughness. The electrochemical behavior of the generated gold surface was studied by cyclic voltammetry showing the characteristic response of polycrystalline gold, in contrast with disposable gold electrodes fabricated by screen printing from gold inks. The electrodes were chemically modified through the adsorption of alkanethiols self-assembled monolayers and the coupling of a model protein. Both reactions were followed by cyclic voltammetry and Electrochemical Impedance Spectroscopy (EIS). The electrodes have shown high reproducibility in their electrochemical behavior as well as in their modifications. [source] An In Situ Copper Plated Boron-Doped Diamond Microelectrode Array for the Sensitive Electrochemical Detection of NitrateELECTROANALYSIS, Issue 20 2005Sarah Ward-Jones Abstract The first example of using a copper microelectrode array for use in electroanalysis is explored and exemplified with the electroanalytical quantification of nitrate. The analytical approach is based upon the in situ deposition of copper at a boron-doped diamond (BDD) microelectrode array. The immobilized copper layer is electrocatalytic for nitrate reduction and exhibits an analytically useful range from 1.2 to 124,,M with a marked selectivity for nitrate ion over nitrate, with a limit of detection of 0.76,,M. The analytical applicability was examined through standard addition determinations of nitrate in drinking and river water samples. [source] Analysis of Simulated Martian Regolith Using an Array of Ion Selective ElectrodesELECTROANALYSIS, Issue 15-16 2005Stefan Abstract A prototype miniature array of polymer membrane and solid state ion selective electrodes was developed for the purpose of performing an in-situ analysis of the soluble ionic species in Martian regolith (soil). The array contains a total of 27 electrodes for K+, Na+, Ca2+, Mg2+, NH, Ba2+, NO, Cl,, and Li+, each in triplicate. Barium electrodes were used to indirectly monitor sulfate through precipitation by the addition of barium chloride while the lithium electrodes served as a reference for the array by having a constant lithium concentration as a background for all solutions. The array was tested with several types of simulants, soils, and sawdust from a Mars meteorite, all with varying salt content, meant to approximate the various hypotheses regarding the ionic composition of the Martian soil. The activities of anions and cations determined with the array were compared to ion chromatography data. [source] Energy- and Charge-Transfer Processes in a Perylene,BODIPY,Pyridine Tripartite ArrayEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 16 2008Mohammed A. H. Alamiry Abstract A novel boron dipyrromethene (BODIPY) dye has been synthesized in which the F atoms, usually bound to the boron center, have been replaced with 1-ethynylperylene units and a 4-pyridine residue is attached at the meso -position. The perylene units function as photon collectors over the wavelength range from 350 to 480 nm. Despite an unfavorable spectral overlap integral, rapid energy transfer takes place from the singlet-excited state of the perylene unit to the adjacent BODIPY residue, which is itself strongly fluorescent. The mean energy-transfer time is 7,±,2 ps at room temperature. The dominant mechanism for the energy-transfer process is Dexter-type electron exchange, with Förster-type dipole,dipole interactions accounting for less than 10,% of the total transfer probability. There are no indications for light-induced electron transfer in this system, although there is evidence for a nonradiative decay channel not normally seen for F -type BODIPY dyes. This new escape route is further exposed by the application of high pressure. The meso -pyridine group is a passive bystander until protons are added to the system. Then, protonation of the pyridine N atom leads to complete extinction of fluorescence from the BODIPY dye and slight recovery of fluorescence from the perylene units. Quenching of BODIPY-based fluorescence is due to charge-transfer to the pyridinium unit whereas the re-appearance of perylene-based emission is caused by a reduction in the Förster overlap integral upon protonation. Other cations, most notably zinc(II) ions, bind to the pyridine N-atom and induce similar effects but the resultant conjugate is weakly fluorescent.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Heat-Transfer Coefficient for Cellular Materials Modelled as an Array of Elliptic Rods,ADVANCED ENGINEERING MATERIALS, Issue 10 2009Marcelo J. S. de Lemos Convective heat-transfer coefficients in foam-like materials, modelled as an array of elliptic rods, are numerically determined. An incompressible fluid is considered, flowing through an infinite foam-like material with an arbitrary solid temperature. A repetitive cell is identified and periodic boundary conditions are applied. Turbulence is handled with both low and high Reynolds number formulations. The interfacial heat-transfer coefficient is obtained by volume integrating the distributed variables obtained within the cell. The results indicate that, for the same mass-flow rate, materials formed by elliptic rods have a lower interfacial heat-transfer coefficient compared to other media modelled as staggered arrays of square rods. [source] Graphene Solution-Gated Field-Effect Transistor Array for Sensing ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 18 2010Markus Dankerl Abstract Graphene, with its unique combination of physical and electronic properties, holds great promise for biosensor and bioelectronic applications. In this respect, the development of graphene solution-gated field-effect transistor (SGFET) arrays capable of operation in aqueous environments will establish the real potential of graphene in this rapidly emerging field. Here, we report on a facile route for the scalable fabrication of such graphene transistor arrays and provide a comprehensive characterization of their operation in aqueous electrolytes. An on-chip structure for Hall-effect measurements allows the direct determination of charge carrier concentrations and mobilities under electrolyte gate control. The effect of the solution-gate potential on the electronic properties of graphene is explained using a model that considers the microscopic structure of water at the graphene/electrolyte interface. The graphene SGFETs exhibit a high transconductance and correspondingly high sensitivity, together with an effective gate noise as low as tens of ,V. Our study demonstrates that graphene SGFETs, with their facile technology, high transconductance, and low noise promise to far outperform state-of-the-art Si-based devices for biosensor and bioelectronic applications. [source] Cationic Polyelectrolyte Amplified Bead Array for DNA Detection with Zeptomole Sensitivity and Single Nucleotide Polymorphism SelectivityADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Chun Wang Abstract A highly sensitive strand specific DNA assay, which consists of a peptide nucleic acid (PNA) probe, a cationic conjugated polymer (PFVP), and self-assembled polystyrene beads in microwell arrays on silicon chip, is reported. PFVP, as an efficient signal amplifier and signal reporter, has been specially designed and synthesized to be compatible with commercial confocal microscopes for sensing on solid substrates. The assay operates on the net increase in negative charge at the PNA surface that occurs upon single-stranded DNA hybridization, which subsequently allows complex formation with the positively charged PFVP to favor energy transfer between the polymer and Cy5-labeled target. With maximized surface contact provided by bead arrays and signal amplification provided by PFVP, this assay allows detection of ,300 copies of Cy5-labeled DNA using a commercial confocal microscope. In addition, the same strategy is also extended for label-free DNA detection with a detection sensitivity of 150 attomole. Excellent discrimination against single nucleotide polymorphism (SNP) is also demonstrated for both Cy5-labeled and label-free target detection. This study indicates that cationic conjugated polymers have great potential to be incorporated into the widely used microarray technology for simplified process with improved detection sensitivity. [source] Electrochemical Method for Synthesis of a ZnFe2O4/TiO2 Composite Nanotube Array Modified Electrode with Enhanced Photoelectrochemical ActivityADVANCED FUNCTIONAL MATERIALS, Issue 13 2010Yang Hou Abstract An electrode with intimate and well-aligned ZnFe2O4/TiO2 composite nanotube arrays is prepared via electrochemical anodization of pure titanium foil in fluorine-containing ethylene glycol, followed by a novel cathodic electrodeposition method. The deposition of ZnFe2O4 is promoted in the self-aligned, vertically oriented TiO2 nanotube arrays but minimized at the tube entrances. Thus, pore clogging is prevented. Environmental scanning electron microscopy, energy-dispersive X-ray spectra, high-resolution transmission electron microscopy, X-ray diffraction patterns, and X-ray photoelectron spectroscopy indicate that the as-prepared samples are highly ordered and vertically aligned TiO2 nanotube arrays with ZnFe2O4 nanoparticles loading. The TiO2 nanotubes are anatase with the preferential orientation of <101> plane. Enhanced absorption in both UV and visible light regions is observed for the composite nanotube arrays. The current,voltage curve of ZnFe2O4 -loaded TiO2 nanotube arrays reveals a rectifying behavior. The enhanced separation of photoinduced electrons and holes is demonstrated by surface photovoltage and photocurrent measurements. Meanwhile, the photoelectrochemical investigations verify that the ZnFe2O4/TiO2 composite nanotube array modified electrode has a more effective photoconversion capability than the aligned TiO2 nanotube arrays alone. In addition, the photoelectrocatalytic ability of the novel electrode is found enhanced in the degradation of 4-chlorophenol. [source] Enhanced Fluorescence Microscopic Imaging by Plasmonic Nanostructures: From a 1D Grating to a 2D Nanohole ArrayADVANCED FUNCTIONAL MATERIALS, Issue 6 2010Xiaoqiang Cui Abstract A two-dimensional (2D) plasmonic coupling nanostructure for enhanced fluorescence observation using a microscope is presented. The substrate contained periodically assembled nanohole arrays with a pitch of 400,nm and a depth of 25,nm. In comparison with one-dimensional (1D) gratings, this new substrate presented an excellent surface plasmon coupling ability to illuminate light from all directions. Under an optical microscope, an enhancement in the fluorescence intensity of up to 100 times compared with a plain glass slide was observed. The ability to markedly increase the fluorescence intensity means this technique has great potential for application in biodiagnostics, imaging, sensing, and photovoltaic cells. [source] Quantum-Dot-Tagged Bioresponsive Hydrogel Suspension Array for Multiplex Label-Free DNA DetectionADVANCED FUNCTIONAL MATERIALS, Issue 6 2010Yuanjin Zhao Abstract A novel hydrogel suspension array, which possesses the joint advantages of quantum-dot-encoded technology, bioresponsive hydrogels, and photonic crystal sensors with full multiplexing label-free DNA detection capability is developed. The microcarriers of the suspension array are quantum-dot-tagged DNA-responsive hydrogel photonic beads. In the case of label-free DNA detection, specific hybridization of target DNA and the crosslinked single-stranded DNA in the hydrogel grid will cause hydrogel shrinking, which can be detected as a corresponding blue shift in the Bragg diffraction peak position of the beads that can be used for quantitatively estimating the amount of target DNA. The results of the label-free DNA detection show that the suspension array has high selectivity and sensitivity with a detection limit of 10,9,M. This method has the potential to provide low cost, miniaturization, and simple and real-time monitoring of hybridization reaction platforms for detecting genetic variations and sequencing genes. [source] Fabrication of a Macroporous Microwell Array for Surface-Enhanced Raman ScatteringADVANCED FUNCTIONAL MATERIALS, Issue 19 2009Martina Zamuner Abstract Here, a colloidal templating procedure for generating high-density arrays of gold macroporous microwells, which act as discrete sites for surface-enhanced Raman scattering (SERS), is reported. Development of such a novel array with discrete macroporous sites requires multiple fabrication steps. First, selective wet-chemical etching of the distal face of a coherent optical fiber bundle produces a microwell array. The microwells are then selectively filled with a macroporous structure by electroless template synthesis using self-assembled nanospheres. The fabricated arrays are structured at both the micrometer and nanometer scale on etched imaging bundles. Confocal Raman microscopy is used to detect a benzenethiol monolayer adsorbed on the macroporous gold and to map the spatial distribution of the SERS signal. The Raman enhancement factor of the modified wells is investigated and an average enhancement factor of 4,×,104 is measured. This demonstrates that such nanostructured wells can enhance the local electromagnetic field and lead to a platform of ordered SERS-active micrometer-sized spots defined by the initial shape of the etched optical fibers. Since the fabrication steps keep the initial architecture of the optical fiber bundle, such ordered SERS-active platforms fabricated onto an imaging waveguide open new applications in remote SERS imaging, plasmonic devices, and integrated electro-optical sensor arrays. [source] Diamond Transistor Array for Extracellular Recording From Electrogenic CellsADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Markus Dankerl Abstract The transduction of electric signals from cells to electronic devices is mandatory for medical applications such as neuroprostheses and fundamental research on communication in neuronal networks. Here, the use of diamond with its advantages for biological applications as a new material for biohybrid devices for the detection of cell signals is investigated. Using the surface conductivity of hydrogen-terminated single-crystalline diamond substrates, arrays of solution-gate field-effect transistors were fabricated. The characterization of the transistors reveals a good stability in electrolyte solutions for at least 7 days. On these devices, cardiomyocyte-like HL-1 cells as well as human embryonic kidney cells (HEK293), which were stably transfected with potassium channels, are cultured. Both types of cells show healthy growth and good adhesion to the substrate. The diamond transistors are used to detect electrical signals from both types of cells by recording the extracellular potential. For the HL-1 cells, the shape of action potentials can be resolved and the propagation of the signal across the cell layer is visible. Potassium currents of HEK293 cells are activated with the patch-clamp technique in voltage-clamp mode and simultaneously measured with the field-effect transistors. The ion sensitivity of the diamond surface enables the detection of released potassium ions accumulated in the cleft between transistor and cell. [source] Fabrication of a Superhydrophobic Surface from a Smectic Liquid-Crystal Defect ArrayADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Yun Ho Kim Abstract A novel fabrication method is developed for the preparation of superhydrophobic surfaces. The procedure uses focal conic structures of semi-fluorinated smectic liquid crystals (LCs) whose periodic toric focal conic domains (TFCDs) are prepared on a surface modified substrate. Reactive ion etching (RIE) on the periodic TFCD surface leads to a superhydrophobic surface with a water contact angle of ,160° and a sliding angle of ,2° for a 10,µL water droplet. The results show that this phenomenon is due to the development of a dual-scale surface roughness arising from the nanoscale protuberance caused by applying the RIE process to the top of the microscale TFCD arrays. The unique surface behavior is further verified by demonstrating that RIE on a flat lamellar liquid crystal film, in which the director is aligned parallel with surface, results in a relatively low hydrophobicity as compared to when periodic TFCDs are subjected to REI. The observations made in this publication suggest that a new approach exists for selecting potential candidates of superhydrophic surface formation based on spontaneous self-assembly in smectic liquid-crystalline materials. [source] A reflector at 200 km depth beneath the northwest PacificGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2001S. Rost SUMMARY We present an analysis of precursors to PP produced by underside reflections from discontinuities in the upper mantle beneath the NW Pacific. The events used for this study occur in the western Pacific Rim (New Zealand, Fiji, Tonga, Solomon, New Guinea, Philippine Islands) and are recorded at the short-period Yellowknife Array (YKA) in northern Canada. The source,receiver combination results in PP reflection points which allow us to study the upper mantle structure in a corridor from the Hawaiian Islands to the Kuril subduction zone. To detect the weak precursors in the time window between the P arrival and the PP onset and to identify them as PP underside reflections, special array techniques are used. Our analysis indicates a reflector at a depth of ,200 km beneath the northwestern Pacific. This reflector shows strong topography of some tens of kilometres on length scales of several hundred kilometres, complicating the detection of this reflector in global or regional stacks of seismograms. Different models for the impedance jump across the reflector, the thickness and the possible fine structure of the reflector are modelled using synthetic seismograms and are compared with the data. The thickness of the reflector has to be less than 7 km and the P wave impedance contrast has to be larger than 5.0,6.5 per cent to be detected by this study. This corresponds to a P -velocity jump of ,4 per cent assuming the PREM density model. [source] Phototunable Microlens Array Based on Polymer Dispersed Liquid CrystalsADVANCED FUNCTIONAL MATERIALS, Issue 7 2009Gui-Rong Xiong Abstract A microfluidic system is designed to fabricate polymer dispersed liquid crystal microspheres, whose shape, surface smoothness, and size are controlled. A microlens array (MLA) is constructed by the assembly of the monodispersed microspheres. In the MLA, each microsphere acts as a separate imaging unit. As the liquid crystal (LC) used is a mixed liquid crystal that contain photoresponsive 4-butyl-4-methoxyazobenzene, the imaging capability and light transportation of the MLA can be reversibly controlled by light irradiation. [source] Correlation of hypoxic signalling to histological grade and outcome in cartilage tumoursHISTOPATHOLOGY, Issue 5 2010Stephane Boeuf Boeuf S, Bovée J V M G, Lehner B, Hogendoorn P C W & Richter W (2010) Histopathology56, 641,651 Correlation of hypoxic signalling to histological grade and outcome in cartilage tumours Aims:, The molecular mechanisms underlying the progression of central chondrosarcoma are so far poorly understood. The aim of this study was to identify genes involved in the progression of these tumours by comparison of gene expression and correlation of expression profiles to histological grade and clinical outcome. Methods and results:, Array-based gene expression profiling of 19 chondrosarcoma samples was performed. Beside differences in the expression of cartilage matrix molecules, high-grade chondrosarcoma showed enhanced expression of the matrix metalloproteinase MMP-2 and of the hypoxia-inducible molecule galectin 1. Immunohistochemical analysis of galectin 1 and of further hypoxia-associated proteins was performed on 68 central and peripheral tumour samples. Hypoxia-inducible factor 1, (HIF-1,) activation was significantly elevated in high-grade central chondrosarcoma. A negative correlation of carbonic anhydrase IX expression to metastasis-free survival was independent of histological grade. Conclusions:, The expression patterns identified in this study point towards a substantial role for angiogenic and hypoxic signalling in chondrosarcoma progression. The constitutive activation of the transcription factor HIF-1, in high-grade chondrosarcoma could play a central role in the regulation of cell metabolism and vascularization in these tumours and may, for this reason, represent a potential target for chondrosarcoma therapy. [source] Validation of microarray-based resequencing of 93 worldwide mitochondrial genomes,HUMAN MUTATION, Issue 1 2009Anne Hartmann Abstract The human mitochondrial genome consists of a multicopy, circular dsDNA molecule of 16,569 base pairs. It encodes for 13 proteins, two ribosomal genes, and 22 tRNAs that are essential in the generation of cellular ATP by oxidative phosphorylation in eukaryotic cells. Germline mutations in mitochondrial DNA (mtDNA) are an important cause of maternally inherited diseases, while somatic mtDNA mutations may play important roles in aging and cancer. mtDNA polymorphisms are also widely used in population and forensic genetics. Therefore, methods that allow the rapid, inexpensive and accurate sequencing of mtDNA are of great interest. One such method is the Affymetrix GeneChip® Human Mitochondrial Resequencing Array 2.0 (MitoChip v.2.0) (Santa Clara, CA). A direct comparison of 93 worldwide mitochondrial genomes sequenced by both the MitoChip and dideoxy terminator sequencing revealed an average call rate of 99.48% and an accuracy of ,99.98% for the MitoChip. The good performance was achieved by using in-house software for the automated analysis of additional probes on the array that cover the most common haplotypes in the hypervariable regions (HVR). Failure to call a base was associated mostly with the presence of either a run of ,4,C bases or a sequence variant within 12 bases up- or downstream of that base. A major drawback of the MitoChip is its inability to detect insertions/deletions and its low sensitivity and specificity in the detection of heteroplasmy. However, the vast majority of haplogroup defining polymorphism in the mtDNA phylogeny could be called unambiguously and more rapidly than with conventional sequencing. Hum Mutat 0,1,8, 2008. © 2008 Wiley-Liss, Inc. [source] Testing and improving experimental parameters for the use of low molecular weight targets in array-CGH experiments,HUMAN MUTATION, Issue 11 2006Marianne Stef Abstract Array,comparative genomic hybridization (CGH) has evolved as a useful technique for the detection and characterization of deletions, and, to a lesser extent, of duplications. The resolution of the technique is dictated by the genomic distance between targets spotted on the microarray, and by the targets' sizes. The use of region-specific, high-resolution microarrays is a specific goal when studying regions that are prone to rearrangements, such as those involved in deletion syndromes. The aim of the present study was to evaluate the best experimental conditions to be used for array-CGH analysis using low molecular weight (LMW) targets. The parameters tested were: the target concentration, the way LMW targets are prepared (either as linearized plasmids or as purified PCR products), and the way the targets are attached to the array-CGH slide (in a random fashion on amino-silane coated slides, or by one amino-modified end on epoxysilane-coated slides). As a test case, we constructed a microarray harboring LMW targets located in the CREBBP gene, mutations of which cause the Rubinstein-Taybi syndrome (RTS). From 10 to 15% of RTS patients have a CREBBP deletion. We showed that aminosilane- and epoxysilane-coated slides were equally efficient with targets above 1,000,bp in size. On the other hand, with the smallest targets, especially those below 500,bp, epoxysilane-coated slides were superior to aminosilane-coated slides, which did not allow deletion detection. Use of the high resolution array allowed us to map intragenic breakpoints with precision and to identify a very small deletion and a duplication that were not detected by the currently available techniques for finding CREBBP deletions. Hum Mutat 27(11), 1143,1150, 2006. © 2006 Wiley-Liss, Inc. [source] Scanning Probe Parallel Nanolithography with Multiprobe Cantilever Array Fabricated by Bulk Silicon MicromachiningIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 3 2008Hensy Gandjar Non-member Abstract This work describes a scanning probe parallel nanolithography (SPNL) technique for high throughput in nanometric patterning on single-crystal silicon (SCS) substrates. Two types of multiprobe cantilever arrays used for SPNL were fabricated by conventional micromachining. All the probes mounted on the free end of each cantilever were made of quasitrihedral pyramidal shape composed of (311) and (411) planes using the originally designed mask. Negative and positive types of nanolithography were performed on the basis of field-enhanced anodization and self-assembled monolayer mask techniques, respectively, and they succeeded in drawing a number of nanometric patterns of silicon dioxide (SiO2) on SCS substrates. After anisotropic wet etching of the SCS substrates using the SiO2 films as the mask material, we were also able to fabricate nanowires and nanogrooves. The effects of the applied voltage and scan time of cantilever arrays on wire and groove dimensions were systematically examined by atomic force microscopy (AFM) observations. An optimum condition for the parallel SPNL is proposed on the basis of this research. © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Fabrication of a High-Brightness Blue-Light-Emitting Diode Using a ZnO-Nanowire Array Grown on p-GaN Thin FilmADVANCED MATERIALS, Issue 27 2009Xiao-Mei Zhang Bright n-ZnO nanowire/p-GaN film hybrid heterojunction light-emitting-diode (LED) devices are fabricated by directly growing n-type ZnO-nanowire arrays on p-GaN wafers. UV,blue electroluminescence emission was observed from the heterojunction diodes, and the heterojunction LED device exhibited a high sensitivity in responding to UV irradiation. [source] Tetomilast suppressed production of proinflammatory cytokines from human monocytes and ameliorated chronic colitis in IL-10-deficient miceINFLAMMATORY BOWEL DISEASES, Issue 11 2008Hitoshi Ichikawa MD Abstract Background: Tetomilast (OPC-6535) was originally developed as a compound inhibiting superoxide production in neutrophils. Although its mechanism of action is not completely understood, phosphodiesterase type 4 inhibitory function has been postulated. The therapeutic effect of PDE4 inhibitors has been reported for chronic inflammatory disorders such as chronic obstructive pulmonary diseases. In this study we aimed to examine whether tetomilast could be a novel drug for inflammatory bowel diseases by further clarifying its antiinflammatory effects. Methods: Cytokines from human peripheral blood mononuclear cells were measured by enzyme-linked immunosorbent assay (ELISA) and Cytokine Beads Array. The transcripts were quantified by reverse-transcriptase polymerase chain reaction (RT-PCR). Phosphorylation of transcription factors was examined by phosflow. To examine its in vivo effect, a once-daily oral dose of tetomilast was tested in murine IL-10,/, chronic colitis. Results: Tetomilast suppressed TNF-, and IL-12 but not IL-10 production from lipopolysaccharide (LPS)-stimulated human monocytes. It suppressed TNF-,, IFN-,, and IL-10 from CD4 lymphocytes. Tetomilast suppressed cytokine production at the transcriptional level but did not alter phosphorylation of p65, ERK, p38, and STAT3. HT-89, a protein kinase A inhibitor, did not abolish the effect of tetomilast, suggesting that it was independent from the classical cAMP/PKA pathway. IL-10 was not essential to the inhibitory effect of tetomilast on TNF-, and IL-12. Tetomilast ameliorated IL-10,/, chronic colitis with reduced clinical symptoms, serum amyloid A, and histological scores with decreased TNF-, mRNA expression. Conclusions: Tetomilast exerts its antiinflammatory effects on human monocytes and CD4 cells. Combined with in vivo data these findings support the feasibility of tetomilast as a novel drug for inflammatory bowel diseases. (Inflamm Bowel Dis 2008) [source] Establishment, characterization and drug sensitivity testing in primary cultures of human thymoma and thymic carcinomaINTERNATIONAL JOURNAL OF CANCER, Issue 12 2008Volker Ehemann Abstract Thymomas and thymic carcinomas are peculiar epithelial tumors of the anterior mediastinum. They may show aggressive clinical behavior and are a paradigm for the interaction between the tumor and the immune system. So far, adequate functional studies enabling a better understanding of this malignancy have not been performed, since human thymoma/thymic carcinoma cell lines have not been available. Here, the authors describe the establishment, characterization and functional analyses of epithelial cell lines from a Type B1-thymoma and a poorly differentiated thymic carcinoma. By Fluorescence-activated cell sorting (FACS) analyses, both cell lines were aneuploid. The aneuploid cell fraction of the thymic carcinoma cell line was characterized by a high proliferation index of 55.9%, in contrast to a lower proliferation rate of the aneuploid cell fraction of the thymoma (19.7%). Array-based comparative genomic hybridization (aCGH) and conventional cytogenetic analysis of the thymoma revealed only minor imbalances whereas the thymic carcinoma was characterized by a complex karyotype in the hyperdiploid range that was readily defined with multicolor FISH (mFISH). Application of a selective COX-2 inhibitor reduced cell viability in both cell lines in a dose-dependent manner. In conclusion, these first cell lines of a thymoma and a CD5-positive thymic carcinoma are useful tools for further in vitro studies of cellular, molecular and genetic aspects of the disease and for functional tests to evaluate new therapeutic targets. © 2008 Wiley-Liss, Inc. [source] Three-Dimensional Nanonetwork Assembled in a Photopolymerized Rod ArrayADVANCED MATERIALS, Issue 23 2003H.-B. Sun One- and two-photon interferential patterning of photopolymerizable resin is demonstrated to lead to well-defined two-dimensional (2D) photonic crystal structures (which beat the diffraction limit) and also 3D nanonetworks, such as that shown in the Figure. The fiber-like features are probably formed by a novel self-assembly mechanism during drying. Applications in photonics are foreseen. [source] Subcutaneous Array to Transvenous Proximal Coil Defibrillation as a Solution to High Defibrillation Thresholds with Implantable Cardioverter Defibrillator Distal Coil FailureJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2003BOAZ AVITALL, Ph.D. Implantation of a subcutaneous array to improve the defibrillation threshold of an existing transvenous defibrillation lead system without the need for lead extraction is discussed.(J Cardiovasc Electrophysiol, Vol. 14, pp. 314-315, March 2003) [source] | ||||||||||||||||||||||||||||||||||