Science.gov

Sample records for suspension array analysis

  1. Novel design for suspension array detection system

    NASA Astrophysics Data System (ADS)

    Xu, Guoxiong; Shi, Yan; Ni, Xuxiang; Lu, Zukang

    2005-01-01

    This paper presents a novel method for establishing a two-dimensional laminar fluidic suspension array which is analyzed by using time delay integration (TDI) CCD imaging technology in parallel. The method will make suspension array technology (SAT) bear high throughput as well as its flexibility. Basically, bioassays are conducted on the surface of fluorescent-dyed beads. With each bead set (i.e., multiple beads with the same fluorescent signature) having a slightly different fluorescent signature, probes are first attached to a particular bead set and then hybridized with labeled samples or targets. Two different kinds of encoding dyes are excited by red laser (635 nm, 20mw), their emission wave length are 660nm, 720nm, respectively. Fluorescent dye of reporter molecules was excited by green laser (532nm, 20mw), emitted at 580 nm. The liquid sample was pumped into micro-reservoir by a linear motor. As the velocity of liquid sample is so slow (10mm/s) it is easy to form a laminar fluidic field in the middle of the micro-reservoir. In the direction of laser propagation the size of reservoir is 0.1mm so the laminar liquid can be treated as a two-dimensional fluidic plane. The size of detection area depends on size of micro-sphere and CCD imaging area. The three kinds of fluorescence signals were focused by a lens and then split by mirrors. Fluorescence pass through three band-pass filters (+/-20nm) before collected by three TDI-CCDs respectively. With these high-quality filters the cross-talk between signals was diminished significantly. The analysis speed is about 2x103 micro-spheres per second, which is much higher than that obtained from currently cytometry method (about 102 micro-spheres to the same size micro-spheres).

  2. Highly specific detection of thrombin using an aptamer-based suspension array and the interaction analysis via microscale thermophoresis.

    PubMed

    Liu, Yanan; Liu, Nan; Ma, Xinhua; Li, Xiaoli; Ma, Jia; Li, Ya; Zhou, Zhijiang; Gao, Zhixian

    2015-04-21

    A novel aptamer-based suspension array detection platform was designed for the sensitive, specific and rapid detection of human α-thrombin as a model. Thrombin was first recognized by a 29-mer biotinylated thrombin-binding aptamer (TBA) in solution. Then 15-mer TBA modified magnetic beads (MBs) captured the former TBA-thrombin to form an aptamer-thrombin-aptamer sandwich complex. The median fluorescence intensity obtained via suspension array technology was positively correlated with the thrombin concentration. The interactions between TBAs and thrombin were analyzed using microscale thermophoresis (MST). The dissociation constants could be respectively achieved to be 44.2 ± 1.36 nM (TBA1-thrombin) and 15.5 ± 0.637 nM (TBA2-thrombin), which demonstrated the high affinities of TBA-thrombin and greatly coincided with previous reports. Interaction conditions such as temperature, reaction time, and coupling protocol were optimized. The dynamic quantitative working range of the aptamer-based suspension array was 18.37-554.31 nM, and the coefficients of determination R(2) were greater than 0.9975. The lowest detection limit of thrombin was 5.4 nM. This method was highly specific for thrombin without being affected by other analogs and interfering proteins. The recoveries of thrombin spiked in diluted human serum were in the range 82.6-114.2%. This innovative aptamer-based suspension array detection platform not only exhibits good sensitivity based on MBs facilitating highly efficient separation and amplification, but also suggests high specificity by the selective aptamer binding, thereby suggesting the expansive application prospects in research and clinical fields.

  3. Digital barcodes of suspension array using laser induced breakdown spectroscopy

    PubMed Central

    He, Qinghua; Liu, Yixi; He, Yonghong; Zhu, Liang; Zhang, Yilong; Shen, Zhiyuan

    2016-01-01

    We show a coding method of suspension array based on the laser induced breakdown spectroscopy (LIBS), which promotes the barcodes from analog to digital. As the foundation of digital optical barcodes, nanocrystals encoded microspheres are prepared with self-assembly encapsulation method. We confirm that digital multiplexing of LIBS-based coding method becomes feasible since the microsphere can be coded with direct read-out data of wavelengths, and the method can avoid fluorescence signal crosstalk between barcodes and analyte tags, which lead to overall advantages in accuracy and stability to current fluorescent multicolor coding method. This demonstration increases the capability of multiplexed detection and accurate filtrating, expanding more extensive applications of suspension array in life science. PMID:27808270

  4. Suspension Array Analysis of 16S rRNA from Fe- and SO42-Reducing Bacteria in Uranium-Contaminated Sediments Undergoing Bioremediation

    PubMed Central

    Chandler, Darrell P.; Jarrell, Ann E.; Roden, Eric R.; Golova, Julia; Chernov, Boris; Schipma, Matthew J.; Peacock, Aaron D.; Long, Philip E.

    2006-01-01

    A 16S rRNA-targeted tunable bead array was developed and used in a retrospective analysis of metal- and sulfate-reducing bacteria in contaminated subsurface sediments undergoing in situ U(VI) bioremediation. Total RNA was extracted from subsurface sediments and interrogated directly, without a PCR step. Bead array validation studies with total RNA derived from 24 isolates indicated that the behavior and response of the 16S rRNA-targeted oligonucleotide probes could not be predicted based on the primary nucleic acid sequence. Likewise, signal intensity (absolute or normalized) could not be used to assess the abundance of one organism (or rRNA) relative to the abundance of another organism (or rRNA). Nevertheless, the microbial community structure and dynamics through time and space and as measured by the rRNA-targeted bead array were consistent with previous data acquired at the site, where indigenous sulfate- and iron-reducing bacteria and near neighbors of Desulfotomaculum were the organisms that were most responsive to a change in injected acetate concentrations. Bead array data were best interpreted by analyzing the relative changes in the probe responses for spatially and temporally related samples and by considering only the response of one probe to itself in relation to a background (reference) environmental sample. By limiting the interpretation of the data in this manner and placing it in the context of supporting geochemical and microbiological analyses, we concluded that ecologically relevant and meaningful information can be derived from direct microarray analysis of rRNA in uncharacterized environmental samples, even with the current analytical uncertainty surrounding the behavior of individual probes on tunable bead arrays. PMID:16820459

  5. Simultaneous and rapid detection of multiple pesticide and veterinary drug residues by suspension array technology.

    PubMed

    Liu, Nan; Gao, Zhixian; Ma, Hongwei; Su, Pu; Ma, Xinhua; Li, Xiaoli; Ou, Guorong

    2013-03-15

    Suspension array technology is proposed for the simultaneous quantitative determination of seven kinds of pesticide and veterinary drug residues, namely, atrazine, chloramphenicol, carbaryl, clenbuterol, 17-β-estradiol, imidacloprid, and tylosin. The assay is simple and can be accomplished within 2h without repeated pumping and washing steps unlike conventional suspension arrays. The hapten-protein conjugate-coated beads bind to their complementary biotinylated antibodies using a competitive immunoassay format. The coefficients of determination R(2) for six targets were greater than 0.992, whereas that for atrazine was 0.961, which indicate good logistic correlations. The dynamic ranges for the seven targets in the 7-plex assay ranged from 2 log units to 4 log units(1.60×10(0)-1.64×10(3), 5.12×10(-2)-1.60×10(2), 1.00×10(0)-3.13×10(3), 4.00×10(-1)-4.10×10(2), 4.00×10(-1)-4.10×10(2), 5.12×10(-2)-1.60×10(2), and 2.00×10(0)-4.00×10(2)ngmL(-1)). The minimum detection concentrations of chloramphenicol, carbaryl, clenbuterol and 17-β-estradiol in the suspension array (0.05, 1.00, 0.40 and 0.40 ng mL(-1)) were lower than the corresponding limits of detection (0.25, 6.60, 24.23 and 13.96 ng mL(-1)) of using an indirect competitive enzyme-linked immunosorbent assay. Environmental scanning electron microscope was employed to characterize the bead surface, which directly confirmed the reactions on the beads. The suspension array is more flexible and feasible than ELISA for the fast quantitative analysis of pesticide and veterinary drug residues.

  6. Simultaneous Detection of Fenitrothion and Chlorpyrifos-Methyl with a Photonic Suspension Array

    PubMed Central

    Wang, Xuan; Mu, Zhongde; Shangguan, Fengqi; Liu, Ran; Pu, Yuepu; Yin, Lihong

    2013-01-01

    A technique was developed for simultaneous detection of fenitrothion (FNT) and chlorpyrifos-methyl (CLT) using a photonic suspension array based on silica colloidal crystal beads (SCCBs). The SCCBs were encoded with the characteristic reflection peak originating from the stop-band of colloidal crystal. This approach avoids the bleaching, fading or potential interference seen when encoding by fluorescence. SCCBs with a nanopatterned surface had increased biomolecule binding capacity and improved stability. Under optimal conditions, the proposed suspension array allowed simultaneous detection of the selected pesticides in the ranges of 0.25 to 1024 ng/mL and 0.40 to 735.37 ng/mL, with the limits of detection (LODs) of 0.25 and 0.40 ng/mL, respectively. The suspension array was specific and had no significant cross-reactivity with other chemicals. The mean recoveries in tests in which samples were spiked with target standards were 82.35% to 109.90% with a standard deviation within 9.93% for CLT and 81.64% to 108.10% with a standard deviation within 8.82% for FNT. The proposed method shows a potentially powerful capability for fast quantitative analysis of pesticide residues. PMID:23805266

  7. Comparative protein profiling of serum and plasma using an antibody suspension bead array approach.

    PubMed

    Schwenk, Jochen M; Igel, Ulrika; Kato, Bernet S; Nicholson, George; Karpe, Fredrik; Uhlén, Mathias; Nilsson, Peter

    2010-02-01

    In the pursuit towards a systematic analysis of human diseases, array-based approaches within antibody proteomics offer high-throughput strategies to discover protein biomarkers in serum and plasma. To investigate the influence of sample preparation on such discovery attempts, we report on a systematic effort to compare serum and plasma protein profiles determined with an antibody suspension bead array. The intensity levels were used to define protein profiles and no significant differences between serum and plasma were observed for 79% of the 174 antibodies (targeting 156 proteins). By excluding 36 antibodies giving rise to differential intensity levels, cluster analysis revealed donor-specific rather than preparation-dependent grouping. With a cohort from a clinically relevant medical condition, the metabolic syndrome, the influence of the sample type on a multiplexed biomarker discovery approach was further investigated. Independent comparisons of protein profiles in serum and plasma revealed an antibody targeting ADAMTSL-4, a protein that would qualify to be studied further in association with the condition. In general, the preparation type had an impact on the results of the applied antibody suspension bead array, and while the technical variability was equal, plasma offered a greater biological variability and allowed to give rise to more discoveries than serum.

  8. Suspension arrays based on nanoparticle-encoded microspheres for high-throughput multiplexed detection

    PubMed Central

    Leng, Yuankui

    2017-01-01

    Spectrometrically or optically encoded microsphere based suspension array technology (SAT) is applicable to the high-throughput, simultaneous detection of multiple analytes within a small, single sample volume. Thanks to the rapid development of nanotechnology, tremendous progress has been made in the multiplexed detecting capability, sensitivity, and photostability of suspension arrays. In this review, we first focus on the current stock of nanoparticle-based barcodes as well as the manufacturing technologies required for their production. We then move on to discuss all existing barcode-based bioanalysis patterns, including the various labels used in suspension arrays, label-free platforms, signal amplification methods, and fluorescence resonance energy transfer (FRET)-based platforms. We then introduce automatic platforms for suspension arrays that use superparamagnetic nanoparticle-based microspheres. Finally, we summarize the current challenges and their proposed solutions, which are centered on improving encoding capacities, alternative probe possibilities, nonspecificity suppression, directional immobilization, and “point of care” platforms. Throughout this review, we aim to provide a comprehensive guide for the design of suspension arrays, with the goal of improving their performance in areas such as multiplexing capacity, throughput, sensitivity, and cost effectiveness. We hope that our summary on the state-of-the-art development of these arrays, our commentary on future challenges, and some proposed avenues for further advances will help drive the development of suspension array technology and its related fields. PMID:26021602

  9. A decoupled control approach for magnetic suspension systems using electromagnets mounted in a planar array

    NASA Technical Reports Server (NTRS)

    Groom, Nelson J.

    1993-01-01

    A decoupled control approach for a Large Gap Magnetic Suspension System (LGMSS) is presented. The control approach is developed for an LGMSS which provides five degree-of-freedom control of a cylindrical suspended element that contains a core composed of permanent magnet material. The suspended element is levitated above five electromagnets mounted in a planar array. Numerical results are obtained by using the parameters of the Large Angle Magnetic Suspension Test Fixture (LAMSTF) which is a small scale laboratory model LGMSS.

  10. Quantitative, multiplexed detection of Salmonella and other pathogens by Luminex xMAP suspension array.

    PubMed

    Dunbar, Sherry A; Jacobson, James W

    2007-01-01

    We describe a suspension array hybridization assay for rapid detection and identification of Salmonella and other bacterial pathogens using Luminex xMAP technology. The Luminex xMAP system allows simultaneous detection of up to 100 different targets in a single multiplexed reaction. Included in the method are the procedures for (1) design of species-specific oligonucleotide capture probes and PCR amplification primers, (2) coupling oligonucleotide capture probes to carboxylated microspheres, (3) hybridization of coupled microspheres to oligonucleotide targets, (4) production of targets from DNA samples by PCR amplification, and (5) detection of PCR-amplified targets by direct hybridization to probe-coupled microspheres. The Luminex xMAP suspension array hybridization assay is rapid, requires few sample manipulations, and provides adequate sensitivity and specificity to detect and differentiate Salmonella and nine other test organisms through direct detection of species-specific DNA sequences.

  11. Development of a bead-based suspension array for the detection of pathogens in acute respiratory tract infections

    PubMed Central

    Li, Hong-Ru; Zhang, Wei; Hua, Zhi-Dan; Lin, Xiao-Hong; Lin, Meng-Qing; Huang, Wen-Sen; Huang, Li-Ping; Yu, Xiao-Li; Xu, Neng-Luan; Lin, Ming; Xie, Bao-Song; Shen, Xiao-Na; Xie, Jian-Feng; Wang, Yi; Huang, Meng; Wu, Yan-An; Hu, Xin-Lan

    2016-01-01

    We developed a high-throughput bead-based suspension array for simultaneous detection of 20 respiratory tract pathogens in clinical specimens. Pathogen-specific genes were amplified and hybridized to probes coupled to carboxyl-encoded microspheres. Fluorescence intensities generated via the binding of phycoerythrin-conjugated streptavidin with biotin-labeled targets were measured by the Luminex 100 bead-based suspension array system. The bead-based suspension array detected bacteria in a significantly higher number of samples compared to the conventional culture. There was no significant difference in the detection rate of atypical pathogensatypical pathogens or viruses between the bead-based suspension array and real-time PCR. This technology can play a significant role in screening patients with pneumonia. PMID:27190247

  12. A bead-based suspension array for the multiplexed detection of begomoviruses and their whitefly vectors.

    PubMed

    van Brunschot, S L; Bergervoet, J H W; Pagendam, D E; de Weerdt, M; Geering, A D W; Drenth, A; van der Vlugt, R A A

    2014-03-01

    Bead-based suspension array systems enable simultaneous fluorescence-based identification of multiple nucleic acid targets in a single reaction. This study describes the development of a novel approach to plant virus and vector diagnostics, a multiplexed 7-plex array that comprises a hierarchical set of assays for the simultaneous detection of begomoviruses and Bemisia tabaci, from both plant and whitefly samples. The multiplexed array incorporates genus, species and strain-specific assays, offering a unique approach for identifying both known and unknown viruses and B. tabaci species. When tested against a large panel of sequence-characterized begomovirus and whitefly samples, the array was shown to be 100% specific to the homologous target. Additionally, the multiplexed array was highly sensitive, efficiently and concurrently determining both virus and whitefly identity from single viruliferous whitefly samples. The detection limit for one assay within the multiplexed array that specifically detects Tomato yellow leaf curl virus-Israel (TYLCV-IL) was quantified as 200fg of TYLCV-IL DNA, directly equivalent to that of TYLCV-specific qPCR. Highly reproducible results were obtained over multiple tests. The flexible multiplexed array described in this study has great potential for use in plant quarantine, biosecurity and disease management programs worldwide.

  13. Comparison of two suspension arrays for simultaneous detection of five biothreat bacterial in powder samples.

    PubMed

    Yang, Yu; Wang, Jing; Wen, Haiyan; Liu, Hengchuan

    2012-01-01

    We have developed novel Bio-Plex assays for simultaneous detection of Bacillus anthracis, Yersinia pestis, Brucella spp., Francisella tularensis, and Burkholderia pseudomallei. Universal primers were used to amplify highly conserved region located within the 16S rRNA amplicon, followed by hybridized to pathogen-specific probes for identification of these five organisms. The other assay is based on multiplex PCR to simultaneously amplify five species-specific pathogen identification-targeted regions unique to individual pathogen. Both of the two arrays are validated to be flexible and sensitive for simultaneous detection of bioterrorism bacteria. However, universal primer PCR-based array could not identify Bacillus anthracis, Yersinia pestis, and Brucella spp. at the species level because of the high conservation of 16S rDNA of the same genus. The two suspension arrays can be utilized to detect Bacillus anthracis sterne spore and Yersinia pestis EV76 from mimic "write powder" samples, they also proved that the suspension array system will be valuable tools for diagnosis of bacterial biothreat agents in environmental samples.

  14. Comparison of Two Suspension Arrays for Simultaneous Detection of Five Biothreat Bacterial in Powder Samples

    PubMed Central

    Yang, Yu; Wang, Jing; Wen, Haiyan; Liu, Hengchuan

    2012-01-01

    We have developed novel Bio-Plex assays for simultaneous detection of Bacillus anthracis, Yersinia pestis, Brucella spp., Francisella tularensis, and Burkholderia pseudomallei. Universal primers were used to amplify highly conserved region located within the 16S rRNA amplicon, followed by hybridized to pathogen-specific probes for identification of these five organisms. The other assay is based on multiplex PCR to simultaneously amplify five species-specific pathogen identification-targeted regions unique to individual pathogen. Both of the two arrays are validated to be flexible and sensitive for simultaneous detection of bioterrorism bacteria. However, universal primer PCR-based array could not identify Bacillus anthracis, Yersinia pestis, and Brucella spp. at the species level because of the high conservation of 16S rDNA of the same genus. The two suspension arrays can be utilized to detect Bacillus anthracis sterne spore and Yersinia pestis EV76 from mimic “write powder” samples, they also proved that the suspension array system will be valuable tools for diagnosis of bacterial biothreat agents in environmental samples. PMID:22690123

  15. Nanoelectrode array for electrochemical analysis

    DOEpatents

    Yelton, William G.; Siegal, Michael P.

    2009-12-01

    A nanoelectrode array comprises a plurality of nanoelectrodes wherein the geometric dimensions of the electrode controls the electrochemical response, and the current density is independent of time. By combining a massive array of nanoelectrodes in parallel, the current signal can be amplified while still retaining the beneficial geometric advantages of nanoelectrodes. Such nanoelectrode arrays can be used in a sensor system for rapid, non-contaminating field analysis. For example, an array of suitably functionalized nanoelectrodes can be incorporated into a small, integrated sensor system that can identify many species rapidly and simultaneously under field conditions in high-resistivity water, without the need for chemical addition to increase conductivity.

  16. Open-loop characteristics of magnetic suspension systems using electromagnets mounted in a planar array

    NASA Technical Reports Server (NTRS)

    Groom, Nelson J.; Britcher, Colin P.

    1992-01-01

    The open-loop characteristics of a Large-Gap Magnetic Suspension System (LGMSS) were studied and numerical results are presented. The LGMSS considered provides five-degree-of-freedom control. The suspended element is a cylinder that contains a core composed of permanent magnet material. The magnetic actuators are air core electromagnets mounted in a planar array. Configurations utilizing five, six, seven, and eight electromagnets were investigated and all configurations were found to be controllable from coil currents and observable from suspended element positions. Results indicate that increasing the number of coils has an insignificant effect on mode shapes and frequencies.

  17. Species-specific identification of seven vegetable oils based on suspension bead array.

    PubMed

    Li, Yuanyuan; Wu, Yajun; Han, Jianxun; Wang, Bin; Ge, Yiqiang; Chen, Ying

    2012-03-07

    Species adulteration of vegetable oils has become a main form of adulteration in vegetable oils, severely violating consumer rights and causing disorder in the market. A reliable method of species authentication of vegetable oils is desirable. This paper reports a novel method for identification of seven species of vegetable oils based on suspension bead array. One pair of universal primers and seven species-specific probes were designed targeting rbcl gene of the chloroplast. Each probe was coupled to a unique color-coded microsphere. Biotinylated PCR amplicons of seven oils were hybridized to the complementary probes on microsphere sets. Bound amplicons were detected fluorometrically using a reporter dye, streptavidin-R-phycoeryt hrin (SA-PE). A sample could be analyzed less than 1 h after PCR amplification. With the exception of olive probe, all probes showed no cross-reactivity with other species. Absolute detection limit of the seven probes ranged from 0.01 ng/μL to 0.0001 ng/μL. Detection limit in DNA mixture was from 10% to 5%. Detection of vegetable oils validated the effectiveness of the method. The suspension bead array as a rapid, sensitive, and high-throughput technology has potential to identify more species of vegetable oils with increased species of probes.

  18. A photonic crystal hydrogel suspension array for the capture of blood cells from whole blood

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Cai, Yunlang; Shang, Luoran; Wang, Huan; Cheng, Yao; Rong, Fei; Gu, Zhongze; Zhao, Yuanjin

    2016-02-01

    Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells.Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06368j

  19. Implementation of a decoupled controller for a magnetic suspension system using electromagnets mounted in a planar array

    NASA Technical Reports Server (NTRS)

    Cox, D. E.; Groom, N. J.

    1994-01-01

    An implementation of a decoupled, single-input/single-output control approach for a large angle magnetic suspension test fixture is described. Numerical and experimental results are presented. The experimental system is a laboratory model large gap magnetic suspension system which provides five degree-of-freedom control of a cylindrical suspended element. The suspended element contains a core composed of permanent magnet material and is levitated above five electromagnets mounted in a planar array.

  20. Monoclonal antibody selection for interleukin-4 quantification using suspension arrays and forward-phase protein microarrays.

    PubMed

    Wang, L; Cole, K D; Peterson, A; He, Hua-Jun; Gaigalas, A K; Zong, Y

    2007-12-01

    A recombinant mouse interleukin-4 (IL-4) and three different purified rat antimouse IL-4 monoclonal antibodies (Mab) with different clonalities were employed as a model system. This system was used to examine monoclonal antibody effectiveness using both conventional and high-throughput measurement techniques to select antibodies for attaining the most sensitive detection of the recombinant IL-4 through the "sandwich-type" immunoassays. Surface plasmon resonance (SPR) measurements and two high-throughput methods, suspension arrays (also called multiplexed bead arrays) and forward-phase protein microarrays, predicted the same capture (BVD4-1D11) and detection (BVD6-24G2) antibody pair for the most sensitive detection of the recombinant cytokine. By using this antibody pair, we were able to detect as low as 2 pg/mL of IL-4 in buffer solution and 13.5 pg/mL of IL-4 spiked in 100% normal mouse serum with the multiplexed bead arrays. Due to the large amount of material required for SPR measurements, the study suggests that the multiplexed bead arrays and protein microarrays are both suited for the selection of numerous antibodies against the same analyte of interest to meet the need in the areas of systems biology and reproducible clinical diagnostics for better patient care.

  1. Optical analysis of red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Szołna, Alicja A.; Grzegorzewski, Bronisław

    2008-12-01

    The optical properties of suspensions of red blood cells (RBCs) were studied. Fresh human venues blood was obtained from adult healthy donors. RBCs were suspended in isotonic salt solution, and in autologous plasma. Suspensions with haematocrit 0.25 - 3% were investigated. Novel technique was proposed to determine the scattering coefficient μs for the suspensions. The intensity of He-Ne laser light transmitted through a wedge-shape container filled with a suspension was recorded. To find the dependence of the intensity on the thickness of the sample the container was moved horizontally. The dependence of μs on the haematocrit was determined for RBCs suspended in the isotonic salt solution. RBCs suspended in plasma tend to form rouleaux. For the RBCs suspended in plasma, the scattering coefficient as a function of time was obtained. It is shown that this technique can be useful in the study of rouleaux formation.

  2. Rapid, Multiplexed Characterization of Shiga Toxin-Producing Escherichia coli (STEC) Isolates Using Suspension Array Technology

    PubMed Central

    Carter, John M.; Lin, Andrew; Clotilde, Laurie; Lesho, Matthew

    2016-01-01

    Molecular methods have emerged as the most reliable techniques to detect and characterize pathogenic Escherichia coli. These molecular techniques include conventional single analyte and multiplex PCR, PCR followed by microarray detection, pulsed-field gel electrophoresis (PFGE), and whole genome sequencing. The choice of methods used depends upon the specific needs of the particular study. One versatile method involves detecting serogroup-specific markers by hybridization or binding to encoded microbeads in a suspension array. This molecular serotyping method has been developed and adopted for investigating E. coli outbreaks. The major advantages of this technique are the ability to simultaneously serotype E. coli and detect the presence of virulence and pathogenicity markers. Here, we describe the development of a family of multiplex molecular serotyping methods for Shiga toxin-producing E. coli, compare their performance to traditional serotyping methods, and discuss the cost-benefit balance of these methods in the context of various food safety objectives. PMID:27242670

  3. Analysis of Train Suspension System Using MR dampers

    NASA Astrophysics Data System (ADS)

    RamaSastry, DVA; Ramana, K. V.; Mohan Rao, N.; Siva Kumar, SVR; Priyanka, T. G. L.

    2016-09-01

    This paper deals with introducing MR dampers to the Train Suspension System for improving the ride comfort of the passengers. This type of suspension system comes under Semi-active suspension system which utilizes the properties of MR fluid to damp the vibrations. In case of high speed trains, the coach body is subjected to vibrations due to vertical displacement, yaw and pitch movements. When the body receives these disturbances from the ground,the transmission of vibrations to the passenger increases which affect the ride comfort. In this work, the equations of motion of suspension system are developed for both conventional passive system and semi-active system and are modelled in Matlab/Simulink and analysis has been carried out. The passive suspension system analysis shows that it is taking more time to damp the vibrations and at the same time the transmissibility of vibrations is more.Introducing MR dampers,vertical and angular displacements of the body are computed and compared. The results show that the introduction of MR dampers into the train suspension system improves ride comfort.

  4. Multiplex detection of B-type natriuretic peptide, cardiac troponin I and C-reactive protein with photonic suspension array.

    PubMed

    Lu, Wenbin; Fu, Cong; Chen, Yong; Lu, Jun; Yao, Yuyu; Shen, Chengxing; Gu, Zhongze

    2012-01-01

    A novel photonic suspension array has been developed for multiplex immunoassay. The carriers of this array were silica colloidal crystal beads (SCCBs). The codes of these carriers have characteristic reflection peaks originating from their structural periodicity; therefore they do not suffer from fading, bleaching, quenching or chemical instability. In addition, the fluorescence background of SCCBs is negligible because no fluorescence materials or dyes are involved. With a sandwich method, the proposed suspension array was used for simultaneous multiplex detection of heart failure (HF) and coronary heart disease (CAD) biomarkers in one test tube. The results showed that the three biomarkers: cardiac troponin I (cTnI), C-reactive protein (CRP) and B-type natriuretic peptide (BNP) could be assayed in the ranges of 0.1-500 ng/ml, 1-500 mg/L and 0.02-50 ng/ml with detection limits of 0.01 ng/ml, 0.36 mg/L and 0.004 ng/ml at 3σ, respectively. There were no significant differences between the photonic suspension array and traditional parallel single-analyte test. This novel method demonstrated acceptable accuracy, high detection sensitivity and reproducibility and excellent storage stability. This technique provides a new strategy for low cost, automated, and simultaneous multiplex immunoassays of bio-markers.

  5. Collision rates for rare cell capture in periodic obstacle arrays strongly depend on density of cell suspension.

    PubMed

    Cimrák, I

    2016-11-01

    Recently, computational modelling has been successfully used for determination of collision rates for rare cell capture in periodic obstacle arrays. The models were based on particle advection simulations where the cells were advected according to velocity field computed from two dimensional Navier-Stokes equations. This approach may be used under the assumption of very dilute cell suspensions where no mutual cell collisions occur. We use the object-in-fluid framework to demonstrate that even with low cell-to-fluid ratio, the optimal geometry of the obstacle array significantly changes. We show computational simulations for ratios of 3.5, 6.9 and 10.4% determining the optimal geometry of the periodic obstacle arrays. It was already previously demonstrated that cells in periodic obstacle arrays follow trajectories in two modes: the colliding mode and the zig-zag mode. The colliding mode maximizes the cell-obstacle collision frequency. Our simulations reveal that for dilute suspensions and for suspensions with cell-to-fluid ratio 3.5%, there is a range of column shifts for which the cells follow colliding trajectories. However we showed, that for 6.9 and 10.4%, the cells never follow colliding trajectories.

  6. High sensitive immunoassay for multiplex mycotoxin detection with photonic crystal microsphere suspension array.

    PubMed

    Deng, Guozhe; Xu, Kun; Sun, Yue; Chen, Yu; Zheng, Tiesong; Li, Jianlin

    2013-03-05

    A novel, sensitive, and high throughput competitive immunoassay for multiplex mycotoxins was established by immobilizing the artificial antigens (Ags) of mycotoxins on the surfaces of three kinds of silica photonic crystal microsphere (SPCM) suspension arrays. The SPCMs were encoded by their reflectance peak positions. Aflatoxin B1 (AFB1), fumonisin B1 (FB1), and citrinin (CIT) spiked in the cereals were extracted, and the fluorescein isothiocyanate (FITC) labeled antibodies (Abs) of these mycotoxins were added into the centrifuge tube which contained the SPCMs of the modified artificial antigens (Ags). The fluorescence signal was collected by an array fluorescent scanner. The limit of detection (LOD) was as low as 0.5, 1, and 0.8 pg/mL for AFB1, FB1, and CIT, respectively. The new method provided a wide linear detection range from 0.001 to 10, 0.001 to 10, and 0.001 to 1 ng/mL for AFB1, FB1, and CIT, respectively. The mean recovery rates are in range of 74.7 ± 4.0% to 127.9 ± 4.4% for the three mycotoxins in corn, peanuts, and wheat. The developed method for mycotoxins was used to assay the AFB1, FB1, and CIT level in 10 naturally contaminated cereal samples, and the results of detection were in agreement with that of a classic enzyme-linked immunosorbent assay (ELISA) method. This method saves a large amount of reagents (10 μL volume) and detection time (<3 h) for multiplex mycotoxin assay.

  7. US Marine Corps assault amphibious vehicle suspension system analysis

    SciTech Connect

    Hammonds, C.J.; Jones, J.K.; Mayhall, J.A.; Williamson, D.E.

    1988-11-01

    In response to a request from the US Marine Corps (USMC), the Oak Ridge National Laboratory investigated a problem with the suspension system of the assault amphibious vehicle (AAV), Personnel Model 7A1. In the course of the investigation, drawings of the AAV and field survey data on bearing failures provided by VSE Corporation were used. The analysis approach taken was to model the suspension system and the vehicle hull and support structure using finite element techniques. This provided stress and deflection information for the system. To determine the loads imparted to the system as the AAV traversed terrain features, a dynamics model was developed to provide loads to the finite element analysis (FEA). Because the primary indication of a problem was frequent suspension-system bearing failure, an analysis of the suspension-system bearings was conducted. Finally, to check the accuracy of the models and to provide actual load data for bearing analysis, an instrumented AAV was tested over a surveyed course at Camp Pendleton, California. Initially the dynamics model assumed the interface between the hull and the suspension system to be fixed. Later improvements incorporating the flexibility of the vehicle hull into the analysis by linking the two models resulted in improved accuracy. Actual measurements of the front road-arm displacement and vertical acceleration of the chassis are compared with predictions from the model. The correlation is quite good and indicates that the model can accurately predict the dynamic load on each road wheel for input into finite element analyses. The dynamics model can be expanded to study the effects of adding weight to the vehicle, traversing other terrains, or evaluating inputs such as weapons firing or drop tests. 7 refs., 75 figs., 10 tabs.

  8. Characterization of microrod arrays by image analysis

    NASA Astrophysics Data System (ADS)

    Hillebrand, Reinald; Grimm, Silko; Giesa, Reiner; Schmidt, Hans-Werner; Mathwig, Klaus; Gösele, Ulrich; Steinhart, Martin

    2009-04-01

    The uniformity of the properties of array elements was evaluated by statistical analysis of microscopic images of array structures, assuming that the brightness of the array elements correlates quantitatively or qualitatively with a microscopically probed quantity. Derivatives and autocorrelation functions of cumulative frequency distributions of the object brightnesses were used to quantify variations in object properties throughout arrays. Thus, different specimens, the same specimen at different stages of its fabrication or use, and different imaging conditions can be compared systematically. As an example, we analyzed scanning electron micrographs of microrod arrays and calculated the percentage of broken microrods.

  9. Development of a Multiplexed Bead-Based Suspension Array for the Detection and Discrimination of Pospiviroid Plant Pathogens

    PubMed Central

    van Brunschot, Sharon L.; Bergervoet, Jan H. W.; Pagendam, Daniel E.; de Weerdt, Marjanne; Geering, Andrew D. W.; Drenth, André; van der Vlugt, René A. A.

    2014-01-01

    Efficient and reliable diagnostic tools for the routine indexing and certification of clean propagating material are essential for the management of pospiviroid diseases in horticultural crops. This study describes the development of a true multiplexed diagnostic method for the detection and identification of all nine currently recognized pospiviroid species in one assay using Luminex bead-based suspension array technology. In addition, a new data-driven, statistical method is presented for establishing thresholds for positivity for individual assays within multiplexed arrays. When applied to the multiplexed array data generated in this study, the new method was shown to have better control of false positives and false negative results than two other commonly used approaches for setting thresholds. The 11-plex Luminex MagPlex-TAG pospiviroid array described here has a unique hierarchical assay design, incorporating a near-universal assay in addition to nine species-specific assays, and a co-amplified plant internal control assay for quality assurance purposes. All assays of the multiplexed array were shown to be 100% specific, sensitive and reproducible. The multiplexed array described herein is robust, easy to use, displays unambiguous results and has strong potential for use in routine pospiviroid indexing to improve disease management strategies. PMID:24404188

  10. Design and analysis of an intelligent controller for active geometry suspension systems

    NASA Astrophysics Data System (ADS)

    Goodarzi, Avesta; Oloomi, Ehsan; Esmailzadeh, Ebrahim

    2011-02-01

    An active geometry suspension (AGS) system is a device to optimise suspension-related factors such as toe angle and roll centre height by controlling vehicle's suspension geometry. The suspension geometry could be changed through control of suspension mounting point's position. In this paper, analysis and control of an AGS system is addressed. First, the effects of suspension geometry change on roll centre height and toe angle are studied. Then, based on an analytical approach, the improvement of the vehicle's stability and handling due to the control of suspension geometry is investigated. In the next section, an eight-degree-of-freedom handling model of a sport utility vehicle equipped with an AGS system is introduced. Finally, a self-tuning proportional-integral controller has been designed, using the fuzzy control theory, to control the actuator that changes the geometry of the suspension system. The simulation results show that an AGS system can improve the handling and stability of the vehicle.

  11. Stability considerations for magnetic suspension systems using electromagnets mounted in a planar array

    NASA Technical Reports Server (NTRS)

    Groom, Nelson J.; Britcher, Colin P.

    1991-01-01

    Mathematical models of a 5, 6, 7, and 8 coil large gap magnetic suspension system (MSDS) are presented. Some of the topics covered include: force and torque equations, reduction of state-space form, natural modes, origins of modes, effect of rotation in azimuth (yaw), future work, and n-coil ring conclusions.

  12. Modeling and analysis of electrorheological suspensions in shear flow.

    PubMed

    Seo, Youngwook P; Seo, Yongsok

    2012-02-14

    A model capable of describing the flow behavior of electrorheological (ER) suspensions under different electric field strengths and over the full range of shear rates is proposed. Structural reformation in the low shear rate region is investigated where parts of a material are in an undeformed state, while aligned structures reform under the shear force. The model's predictions were compared with the experimental data of some ER fluids as well as the CCJ (Cho-Choi-Jhon) model. This simple model's predictions of suspension flow behavior with subsequent aligned structure reformation agreed well with the experimental data, both quantitatively and qualitatively. The proposed model plausibly predicted the static yield stress, whereas the CCJ model and the Bingham model predicted only the dynamic yield stress. The master curve describing the apparent viscosity was obtained by appropriate scaling both axes, which showed that a combination of dimensional analysis and flow curve analysis using the proposed model yielded a quantitatively and qualitatively precise description of ER fluid rheological behavior based on relatively few experimental measurements.

  13. Electrochemical analysis in a liposome suspension using lapachol as a hydrophobic electro active species.

    PubMed

    Okumura, Noriko; Wakamatsu, Shiori; Uno, Bunji

    2014-01-01

    This study demonstrated that the electro-chemical analysis of hydrophobic quinones can be performed in liposome suspension systems. We prepared and analyzed liposome suspensions containing lapachol, which is a quinone-based anti-tumor activity compound. In this suspension system, a simple one redox couple of lapachol is observed. These results are quite different from those obtained in organic solvents. In addition, the pH dependence of redox behaviors of lapachol could be observed in multilamellar vesicle (MLV) suspension system. This MLV suspension system method may approximate the electrochemical behavior of hydrophobic compounds in aqueous conditions. A benefit of this liposome suspension system for electrochemical analysis is that it enables to observe water-insoluble compounds without using organic solvents.

  14. Application of time-frequency analysis to the evaluation of the condition of car suspension

    NASA Astrophysics Data System (ADS)

    Szymański, G. M.; Josko, M.; Tomaszewski, F.; Filipiak, R.

    2015-06-01

    The article presents possibilities of use of vibration signal parameters for the evaluation of elements' clearance in the car suspension system. The time-spectrum analysis has been proposed to determine the frequency band connected with car body free vibration generated by impacts of suspension elements in case of clearance in suspension elements fixing to the car body. Diagnostic models allowing evaluation of shock absorber fastening to the car body are described in this work.

  15. Accurate Analysis of Array References

    DTIC Science & Technology

    1992-09-22

    This thesis addresses the problem of data dependence analysis, the base step in detecting loop level parallelism in scientific programs. Traditional...data dependence analysis research has concentrated on the simpler problem of affine memory disambiguation. Many algorithms have been developed that...can devise an experiment to test the effectiveness of affine memory disambiguation at approximating the full dependence problem. We discover that the

  16. An Analysis of the Mt. Meron Seismic Array

    SciTech Connect

    Pasyanos, M E; Ryall, F

    2008-01-10

    We have performed a quick analysis of the Mt. Meron seismic array to monitor regional seismic events in the Middle East. The Meron array is the only current array in the Levant and Arabian Peninsula and, as such, might be useful in contributing to event location, identification, and other analysis. Here, we provide a brief description of the array and a review of the travel time and array analysis done to assess its performance.

  17. Performance Analysis of ICA in Sensor Array

    PubMed Central

    Cai, Xin; Wang, Xiang; Huang, Zhitao; Wang, Fenghua

    2016-01-01

    As the best-known scheme in the field of Blind Source Separation (BSS), Independent Component Analysis (ICA) has been intensively used in various domains, including biomedical and acoustics applications, cooperative or non-cooperative communication, etc. While sensor arrays are involved in most of the applications, the influence on the performance of ICA of practical factors therein has not been sufficiently investigated yet. In this manuscript, the issue is researched by taking the typical antenna array as an illustrative example. Factors taken into consideration include the environment noise level, the properties of the array and that of the radiators. We analyze the analytic relationship between the noise variance, the source variance, the condition number of the mixing matrix and the optimal signal to interference-plus-noise ratio, as well as the relationship between the singularity of the mixing matrix and practical factors concerned. The situations where the mixing process turns (nearly) singular have been paid special attention to, since such circumstances are critical in applications. Results and conclusions obtained should be instructive when applying ICA algorithms on mixtures from sensor arrays. Moreover, an effective countermeasure against the cases of singular mixtures has been proposed, on the basis of previous analysis. Experiments validating the theoretical conclusions as well as the effectiveness of the proposed scheme have been included. PMID:27164100

  18. Detailed analysis of structure and particle trajectories in sheared suspensions

    NASA Astrophysics Data System (ADS)

    Morris, Jeffrey; Katyal, Bhavana

    1999-11-01

    The structure and particle dynamics of sheared suspensions of hard spheres over a range of shear strength to Brownain motion (Péclet number, Pe) have been studied by detailed analysis of extended sampling of Stokesian Dynamics simulations of simple shear. The emphasis is upon large Pe. The structure has been analyzed by decomposition of the pair distribution function, g(r), into spherical harmonics; the harmonics are a complete set for the decompositon. The results indicate a profound and very marked change in structure due to shearing. It is shown that as Pe increases, the structure is increasingly distorted from teh equilibrium spherical symmetry and the number of harmonics required to recompose the original data to within an arbitrary accuracy increases, and this variation depends upon particle fraction. We present information on the content of the dominant harmonics as a function of radial distance for a pair, and interpret the results in terms of preferred directions in the material. Dynamic particle trajectories at time scales long relative to that used for the Brownian step are analyzed in a novel fashion by simple differential geometric measures, such as root mean square path curvature and torsion. Preliminary results illustrate that the path variation from mean flow correlates with the particle stress.

  19. Luminex(®) multiplex bead suspension arrays for the detection and serotyping of Salmonella spp.

    PubMed

    Dunbar, Sherry A; Ritchie, Vivette Brown; Hoffmeyer, Michaela R; Rana, Gunjot S; Zhang, Hongwei

    2015-01-01

    In this chapter we describe two commercially available bead-based molecular assays for detection, identification and serotyping of Salmonella. The xTAG(®) Gastrointestinal Pathogen Panel (GPP) is a qualitative multiplex test for the simultaneous detection of nucleic acids from Salmonella plus 14 other gastroenteritis-causing bacteria, viruses, and parasites from stool specimens. xTAG GPP uses the Luminex(®) xTAG universal array technology for the identification of specific target sequences combined with the xMAP(®) bead multiplexing platform for detection of the targets that were present in the starting sample. The xMAP Salmonella Serotyping Assay (SSA) is a multiplex nucleic acid-based direct hybridization assay for molecular identification of the serotype of Salmonella isolates. In xMAP SSA, target sequences amplified from cultured Salmonella isolates are captured by hybridization to sequence-specific capture probes which have been coupled to the multiplexed bead sets. Herein we provide detailed protocols for each of these assays and present data which describe their performance characteristics for detection and serotyping Salmonella.

  20. Rethinking Suspensions

    ERIC Educational Resources Information Center

    Stetson, Frank H.; Collins, Betty J.

    2010-01-01

    The overrepresentation of the Black and Hispanic subgroups in suspension data is a national problem and a troubling issue for schools and school systems across the United States. In Maryland, an analysis of student suspensions by school districts for the 2006-2007 school year revealed disproportionality issues. In 23 of the 24 jurisdictions,…

  1. Optical position measurement for a large gap magnetic suspension system: Design and performance analysis

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.; Clemmons, James I., Jr.; Shelton, Kevin J.; Duncan, Walter C.

    1994-01-01

    An optical measurement system (OMS) has been designed and tested for a large gap magnetic suspension system (LGMSS). The LGMSS will be used to study control laws for magnetic suspension systems for vibration isolation and pointing applications. The LGMSS features six degrees of freedom and consists of a planar array of electromagnets that levitate and position a cylindrical element containing a permanent magnet core. The OMS provides information on the location and orientation of the element to the LGMSS control system to stabilize suspension. The hardware design of this optical sensing system and the tracking algorithms are presented. The results of analyses and experiments are presented that define the accuracy limits of the optical sensing system and that quantify the errors in position estimation.

  2. Analysis of Rail Vehicle Suspension Spring with Special Emphasis on Curving, Tracking and Tractive Efforts

    NASA Astrophysics Data System (ADS)

    Kumbhalkar, M. A.; Bhope, D. V.; Vanalkar, A. V.

    2016-09-01

    The dynamics of the rail vehicle represents a balance between the forces acting between wheel and rail, the inertia forces and the forces exerted by suspension and articulation. Axial loading on helical spring causes vertical deflection at straight track but failures calls to investigate for lateral and longitudinal loading at horizontal and vertical curves respectively. Goods carrying vehicle has the frequent failures of middle axle inner suspension spring calls for investigation. The springs are analyzed for effect of stress concentration due to centripetal force and due to tractive and breaking effort. This paper also discusses shear failure analysis of spring at curvature and at uphill at various speeds for different loading condition analytically and by finite element analysis. Two mass rail vehicle suspension systems have been analyzed for vibration responses analytically using mathematical tool Matlab Simulink and the same will be evaluated using FFT vibration analyzer to find peak resonance in vertical, lateral and longitudinal direction. The results prove that the suspension acquires high repeated load in vertical and lateral direction due to tracking and curving causes maximum stress concentration on middle axle suspension spring as height of this spring is larger than end axle spring in primary suspension system and responsible for failure of middle axle suspension spring due to high stress acquisition.

  3. Frequency analysis of a semi-active suspension with magneto-rheological dampers

    NASA Astrophysics Data System (ADS)

    Andronic, Florin; Mihai, Ioan; Suciu, Cornel; Beniuga, Marius

    2015-02-01

    Suspension systems for motor vehicles are constantly evolving in order to ensure vehicle stability and traffic safety under all driving conditions. The present work aims to highlight the influence factors in the case of a quarter car model for semi-active suspensions. The functions that must be met by such suspension systems are first presented. Mathematical models for passive systems are first illustrated and then customized for the semi-active case. A simulation diagram was conceived for Matlab Simulink. The obtained simulation results allow conducting a frequency analysis of the passive and semi-active cases of the quarter car model. Various charts for Passive Suspension Transmissibility and for the Effect of Damping on Vertical Acceleration Response were obtained for both passive and semi-active situations. Analysis of obtained results allowed evaluating of the suspension systems behavior and their frequency dependence. Significant differences were found between the behaviors of passive and semi-active suspensions. It was found that semi-active suspensions ensure damping in accordance to the chosen control method, and are much more efficient than passive ones.

  4. Genetic Diversity of O-Antigens in Hafnia alvei and the Development of a Suspension Array for Serotype Detection

    PubMed Central

    Duan, Zhifeng; Niedziela, Tomasz; Lugowski, Czeslaw; Cao, Boyang; Wang, Tianwei; Xu, Lingling; Yang, Baopeng; Liu, Bin; Wang, Lei

    2016-01-01

    Hafnia alvei is a facultative and rod-shaped gram-negative bacterium that belongs to the Enterobacteriaceae family. Although it has been more than 50 years since the genus was identified, very little is known about variations among Hafnia species. Diversity in O-antigens (O-polysaccharide, OPS) is thought to be a major factor in bacterial adaptation to different hosts and situations and variability in the environment. Antigenic variation is also an important factor in pathogenicity that has been used to define clones within a number of species. The genes that are required to synthesize OPS are always clustered within the bacterial chromosome. A serotyping scheme including 39 O-serotypes has been proposed for H. alvei, but it has not been correlated with known OPS structures, and no previous report has described the genetic features of OPS. In this study, we obtained the genome sequences of 21 H. alvei strains (as defined by previous immunochemical studies) with different lipopolysaccharides. This is the first study to show that the O-antigen gene cluster in H. alvei is located between mpo and gnd in the chromosome. All 21 of the OPS gene clusters contain both the wzx gene and the wzy gene and display a large number of polymorphisms. We developed an O serotype-specific wzy-based suspension array to detect all 21 of the distinct OPS forms we identified in H. alvei. To the best of our knowledge, this is the first report to identify the genetic features of H. alvei antigenic variation and to develop a molecular technique to identify and classify different serotypes. PMID:27171009

  5. Computational Methods for the Analysis of Array Comparative Genomic Hybridization

    PubMed Central

    Chari, Raj; Lockwood, William W.; Lam, Wan L.

    2006-01-01

    Array comparative genomic hybridization (array CGH) is a technique for assaying the copy number status of cancer genomes. The widespread use of this technology has lead to a rapid accumulation of high throughput data, which in turn has prompted the development of computational strategies for the analysis of array CGH data. Here we explain the principles behind array image processing, data visualization and genomic profile analysis, review currently available software packages, and raise considerations for future software development. PMID:17992253

  6. Digital controller design: Analysis of the annular suspension pointing system

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The annular suspension and pointing system (ASPS) a payload auxiliary pointing device of the space shuttle is briefly described along with the function of the digital controller. The equations of motion of a simplified plan planar model of the ASPS are derived. Results of computer simulations are discussed.

  7. Non-linear buffeting response analysis of long-span suspension bridges with central buckle

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Li, Aiqun; Zhao, Gengwen; Li, Jian

    2010-06-01

    The rigid central buckle employed in the Runyang Suspension Bridge (RSB) was the first time it was used in a suspension bridge in China. By using a spectral representation method and FFT technique combined with measured data, a 3D fluctuating wind field considering the tower wind effect is simulated. A novel FE model for buffeting analysis is then presented, in which a specific user-defined Matrix27 element in ANSYS is employed to simulate the aeroelastic forces and its stiffness or damping matrices are parameterized by wind velocity and vibration frequency. A nonlinear time history analysis is carried out to study the influence of the rigid central buckle on the wind-induced buffeting response of a long-span suspension bridge. The results can be used as a reference for wind resistance design of long-span suspension bridges with a rigid central buckle in the future.

  8. Viscosity of carbon nanotube suspension using artificial neural networks with principal component analysis

    NASA Astrophysics Data System (ADS)

    Yousefi, Fakhri; Karimi, Hajir; Mohammadiyan, Somayeh

    2016-11-01

    This paper applies the model including back-propagation network (BPN) and principal component analysis (PCA) to estimate the effective viscosity of carbon nanotubes suspension. The effective viscosities of multiwall carbon nanotubes suspension are examined as a function of the temperature, nanoparticle volume fraction, effective length of nanoparticle and the viscosity of base fluids using artificial neural network. The obtained results by BPN-PCA model have good agreement with the experimental data.

  9. Wavelet Analysis for Acoustic Phased Array

    NASA Astrophysics Data System (ADS)

    Kozlov, Inna; Zlotnick, Zvi

    2003-03-01

    Wavelet spectrum analysis is known to be one of the most powerful tools for exploring quasistationary signals. In this paper we use wavelet technique to develop a new Direction Finding (DF) Algorithm for the Acoustic Phased Array (APA) systems. Utilising multi-scale analysis of libraries of wavelets allows us to work with frequency bands instead of individual frequency of an acoustic source. These frequency bands could be regarded as features extracted from quasistationary signals emitted by a noisy object. For detection, tracing and identification of a sound source in a noisy environment we develop smart algorithm. The essential part of this algorithm is a special interacting procedure of the above-mentioned DF-algorithm and the wavelet-based Identification (ID) algorithm developed in [4]. Significant improvement of the basic properties of a receiving APA pattern is achieved.

  10. Instantaneous physico-chemical analysis of suspension-based nanomaterials

    PubMed Central

    Meng, Fanxu; Ugaz, Victor M.

    2015-01-01

    High-throughput manufacturing of nanomaterial-based products demands robust online characterization and quality control tools capable of continuously probing the in-suspension state. But existing analytical techniques are challenging to deploy in production settings because they are primarily geared toward small-batch ex-situ operation in research laboratory environments. Here we introduce an approach that overcomes these limitations by exploiting surface complexation interactions that emerge when a micron-scale chemical discontinuity is established between suspended nanoparticles and a molecular tracer. The resulting fluorescence signature is easily detectable and embeds surprisingly rich information about composition, quantity, size, and morphology of nanoparticles in suspension independent of their agglomeration state. We show how this method can be straightforwardly applied to enable continuous sizing of commercial ZnO nanoparticles, and to instantaneously quantify the anatase and rutile composition of multicomponent TiO2 nanoparticle mixtures pertinent to photocatalysis and solar energy conversion. PMID:25923196

  11. Pinhole array capacitor for oxide integrity analysis

    NASA Technical Reports Server (NTRS)

    Buehler, M. G.; Blaes, B. R.; Pina, C. A.; Griswold, T. W.

    1983-01-01

    The integrity of the metal-poly oxide and the gate oxide was evaluated for several 5-micron CMOS-bulk processes. The pinhole array capacitor consists of diffused and poly fingers that form a network of MOS transistors (elements), which are capped by a deposited oxide and metal layer. The smallest structure used in this study contained about 15,000 elements and the largest structure contained about 68,000 elements. Each structure was divided into several subarrays. The structures are placed a number of times on each wafer. From a yield analysis of the subarrays, the elements per defect were found to be typically in excess of 50,000 elements/defect for the metal-poly oxide and 100,000 elements/defect for the gate oxide. From the switching behavior of the transistors, the gate oxide defects were tentatively identified as gate-to-body shorts rather than gate-to-diffusion shorts.

  12. Pinhole array capacitor for oxide integrity analysis

    NASA Technical Reports Server (NTRS)

    Buehler, M. G.; Blaes, B. R.; Pina, C. A.; Griswold, T. W.

    1985-01-01

    The integrity of the metal-poly oxide and the gate oxide was evaluated for several 5-micron CMOS-bulk process. The pinhole array capacitor consists of diffused and poly fingers that form a network of MOS transistors (elements), which are capped by a deposited oxide and metal layer. The smallest structure used contained about 15,000 elements and the largest structure contained about 68,000 elements. Each structure was divided into several subarrays. The structures are placed a number of times on each wafer. From a yield analysis of the subarrays, the elements per defect were found to be typically in excess of 50,000 elements/defect for the metal-poly oxide and 100,000 elements/defect for the gate oxide. From the switching behavior of the transistors, the gate oxide defects were tentatively identified as gate-to-body shorts rather than gate-to-diffusion shorts.

  13. Mathematical Analysis of a Large-Gap Electromagnetic Suspension System

    NASA Astrophysics Data System (ADS)

    Jump, Addison Benjamin

    In a form of controlled electromagnetic suspension, a permanent magnetic is levitated by a magnetic field; the field is produced by electrical currents passing through coils. These currents are the control input. In a Large -Gap system the coils are at some distance from the suspended body; in general, there is no closed form expression relating the currents to the flux at the point of the suspended body. Thus, in the general case, it is not possible to establish control-theoretic results for this kind of Large -Gap suspension system. It is shown, however, that if the coil placement configuration exhibits a particular cylindrically symmetric structure, expressions can be found relating the coil positions to the flux. These expressions are used to show the existence of a unique equilibrium point and controllability, in five dimensions of control, for a generic form of Large-Gap system. The results are shown to remain true if the suspended body is rotated about a particular axis. Closed form expressions are found for the currents required to suspend the body at these variable orientations. An inequality between difference classes of experimental inputs is shown to be a necessary condition for suspension of the body. It is demonstrated that the addition of coils to the system cannot lead to six dimensions of controllability. Let the system be given by the standard control equationdot x=Ax+Bu Closed form expressions are found for the eigenvalues of A. In the course of proving that some coil placement restrictions may be relaxed, B is shown to be related to the Vandermonde matrix.

  14. A comparative analysis of passive twin tube and skyhook MRF dampers for motorcycle front suspensions

    NASA Astrophysics Data System (ADS)

    Ahmadian, Mehdi; Gravatt, John

    2004-07-01

    A comparative analysis between conventional passive twin tube dampers and skyhook-controlled magneto-rheological fluid (MRF) dampers for motorcycle front suspensions is provided, based on single axis testing in a damper test rig and suspension performance testing in road trials. Performance motorcycles, while boasting extremely light suspension components and competition-ready performance, have an inherent weakness in comfort, as the suspension systems are designed primarily for racing purposes. Front suspension acceleration and shock loading transmit directly through the front suspension triple clamp into the rider's arms and shoulders, causing rapid fatigue in shoulder muscles. Magneto-rheological fluid dampers and skyhook control systems offer an alternative to conventional sport motorcycle suspensions - both performance and comfort can be combined in the same package. Prototype MRF dampers designed and manufactured specifically for this application require no more space than conventional twin tube designs while adding only 1.7 pounds total weight to the system. The MRF dampers were designed for high controllability and low power consumption, two vital considerations for a motorcycle application. The tests conducted include the dampers' force-velocity curve testing in a damper test rig and suspension performance based on damper position, velocity, and acceleration measurement. Damper test rig results show the MRF dampers have a far greater range of adjustability than the test vehicle's OEM dampers. Combined with a modified sky-hook control system, the MRF dampers can greatly decrease the acceleration and shock loading transmitted to the rider through the handlebars while contributing performance in manners such as anti-dive under braking. Triple clamp acceleration measurements from a variety of staged road conditions, such as sinusoidal wave inputs, will be compared to subjective test-rider field reports to establish a correlation between rider fatigue and the

  15. Array Analysis of North Atlantic Microseisms

    NASA Astrophysics Data System (ADS)

    Craig, David; Bean, Chris; Möllhoff, Martin; Donne, Sarah; Lokmer, Ivan; Le Pape, Florian

    2016-04-01

    Oceans generate persistent low frequency background seismic signals known as microseisms through a mechanical coupling with the Earth's crust. Microseism energy originates as regions of low barometric pressure (depressions) over the oceans where it is transmitted to the sea-floor and propagates as elastic energy in the Earths crust. Consequently microseisms carry important meteorological information relating to both the atmosphere and the hydrosphere. The significance of microseisms as climate indicators has previously been investigated in several studies (Essen et al., 1999; Aster et al., 2010) and to estimate ocean wave parameters using onshore seismometer data (Bromirski et al., 1999). Also many modern seismological methods make use of microseism signals, for example "noise tomography" (Shapiro et al., 2005); spectral ratio techniques ; and cross-correlation techniques (Wapenaar et al., 2011; Brenguier et al., 2014). The continental shelf near Ireland is a known generation are for microseisms and an important region for European weather forecasting and climate studies. There has also been seismometers in the region since the 1960s. There is a single station in Valentia observatory in south-west Ireland and a small scale seismic array in Scotland which offer potential climate records for the region. To make use of this information it is first necessary to understand how microseisms recorded in Ireland relate to the local ocean wavefield. The WAVEOBS project was set established with three primary goals; to get a better fundamental understanding of microseism sources; to investigate the use of ocean generated microseisms as real time ocean wave height data; and to investigate their use as a climate proxy. Using spectral analysis and array methods the microseism wavefield in the North-East Atlantic near Ireland is described with reference to the ocean wavefield.

  16. Three-dimensional nonlinear flutter analysis of long-span suspension bridges during erection.

    PubMed

    Zhang, Xin-jun; Sun, Bing-nan; Xiang, Hai-fan

    2003-01-01

    In this work, the aerodynamic stability of the Yichang Suspension Bridge over Yangtze River during erection was determined by three-dimensional nonlinear flutter analysis, in which the nonlinearities of structural dynamic characteristics and aeroelastic forces caused by large deformation are fully considered. An interesting result obtained was that the bridge was more stable when the stiffening girders were erected in a non-symmetrical manner as opposed to the traditional symmetrical erection schedule. It was also found that the severe decrease in the aerodynamic stability was due to the nonlinear effects. Therefore, the nonlinear factors should be considered accurately in aerodynamic stability analysis of long-span suspension bridges during erection.

  17. Decorrelation correction for nanoparticle tracking analysis of dilute polydisperse suspensions in bulk flow

    NASA Astrophysics Data System (ADS)

    Hartman, John; Kirby, Brian

    2017-03-01

    Nanoparticle tracking analysis, a multiprobe single particle tracking technique, is a widely used method to quickly determine the concentration and size distribution of colloidal particle suspensions. Many popular tools remove non-Brownian components of particle motion by subtracting the ensemble-average displacement at each time step, which is termed dedrifting. Though critical for accurate size measurements, dedrifting is shown here to introduce significant biasing error and can fundamentally limit the dynamic range of particle size that can be measured for dilute heterogeneous suspensions such as biological extracellular vesicles. We report a more accurate estimate of particle mean-square displacement, which we call decorrelation analysis, that accounts for correlations between individual and ensemble particle motion, which are spuriously introduced by dedrifting. Particle tracking simulation and experimental results show that this approach more accurately determines particle diameters for low-concentration polydisperse suspensions when compared with standard dedrifting techniques.

  18. Structural health monitoring of long-span suspension bridges using wavelet packet analysis

    NASA Astrophysics Data System (ADS)

    Ding, Youliang; Li, Aiqun

    2007-09-01

    During the service life of civil engineering structures such as long-span bridges, local damage at key positions may continually accumulate, and may finally result in their sudden failure. One core issue of global vibration-based health monitoring methods is to seek some damage indices that are sensitive to structural damage. This paper proposes an online structural health monitoring method for long-span suspension bridges using wavelet packet transform (WPT). The WPT-based method is based on the energy variations of structural ambient vibration responses decomposed using wavelet packet analysis. The main feature of this method is that the proposed wavelet packet energy spectrum (WPES) has the ability to detect structural damage from ambient vibration tests of a long-span suspension bridge. As an example application, the WPES-based health monitoring system is used on the Runyang Suspension Bridge under daily environmental conditions. The analysis reveals that changes in environmental temperature have a long-term influence on the WPES, while the effect of traffic loadings on the measured WPES of the bridge presents instantaneous changes because of the nonstationary properties of the loadings. The condition indication indices V D reflect the influences of environmental temperature on the dynamic properties of the Runyang Suspension Bridge. The field tests demonstrate that the proposed WPES-based condition indication index V D is a good candidate index for health monitoring of long-span suspension bridges under ambient excitations.

  19. Analysis of impact of suspension rubber mounts on ride comfort

    NASA Astrophysics Data System (ADS)

    Chen, Bao; Chen, Zheming; Lei, Gang

    2017-01-01

    Two multi-body car models with rubber mounts and without rubber mounts have been built up to research how the suspension rubber mounts impact ride comfort. The comfort mount was used to simulate the impact process. Two scenarios have been set up, and time integrations have been performed to get the acceleration-time histories of seat surface in the x-, y-, and z-direction. A MATLAB program was compiled to calculate the weighted RMS acceleration. For the first scenario, the relative difference of weighted RMS acceleration between the car models with rubber mounts and without rubber mounts gradually decreases as the road roughness increases. For the second scenario, the relative difference increases as the driving speed increases. The conclusion shows that the change of driving speed or road roughness impacts ride comfort. Especially for high driving speed this impact is quite obvious.

  20. Digital controller design: Analysis of the annular suspension pointing system

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.

    1979-01-01

    The Annular Suspension and Pointing System (ASPS) is a payload auxiliary pointing device of the Space Shuttle. The ASPS is comprised of two major subassemblies, a vernier and a coarse pointing subsystem. The experiment is attached to a mounting plate/rim combination which is suspended on magnetic bearing/actuators (MBA) strategically located about the rim. Fine pointing is achieved by gimballing the plate/rim within the MBA gaps. Control about the experiment line-of-sight is obtained through the use of a non-contacting rim drive and positioning torquer. All sensors used to close the servo loops on the vernier system are noncontacting elements. Therefore, the experiment is a free-flyer constrained only by the magnetic forces generated by the control loops.

  1. Theoretical and FEM analysis of suspension and propulsion system with HTS hybrid electromagnets in an EMS Maglev model

    NASA Astrophysics Data System (ADS)

    Chung, Y. D.; Lee, C. Y.; Jang, J. Y.; Yoon, Y. S.; Ko, T. K.

    2011-11-01

    We have been constructed a proto-type electromagnetic suspension (EMS) based maglev vehicle system. The maglev concept utilizes magnetic forces for noncontact suspension, guidance and propulsion. The suspension system with high temperature superconducting (HTS) hybrid electromagnet (EM) is composed of HTS coils and normal coils, which consume little power to keep large suspension gap. The magnetic forces realize to guide the vehicle, propel the vehicle along the guide-way and assist in braking action. The proto-type EMS-based Maglev model is designed to keep the suspension gap of 20 mm. This paper presents the theoretical analysis of the maglev vehicle based on the EMS model to obtain the designing parameters for levitation and propulsion forces. The magnetic field distributions of the electromagnetic forces with hybrid EM and propulsion stator coils are analyzed based on three dimension (3D) finite element method (FEM) analysis. From the simulation results, appropriately design parameters of the suspension, guidance and propulsion were obtained.

  2. Rapid O serogroup identification of the ten most clinically relevant STECs by Luminex microbead-based suspension array

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Identification and serotyping of Shiga toxin-producing Escherichia coli during foodborne outbreaks can aid in matching clinical, food, and environmental isolates when trying to identify the sources of illness and ultimately food contamination. Herein we describe a Luminex microbead-based suspension ...

  3. Analysis of cylindrical arrays of microstrip rectangular patches

    NASA Astrophysics Data System (ADS)

    da Silva, C. M.; Lumini, F.; Lacava, J. C. D.; Richards, F. P.

    1991-04-01

    A model for analysis of the radiation characteristics of cylindrical arrays of microstrip rectangular patches is presented. The model is based on the Green function for the multilayered structure calculated in the Fourier domain. The fields radiated by the array are calculated through an asymptotic expression obtained by the application of the stationary phase method. Radiation characteristics such as the directivity function, the ripple and the crosspolarization level are discussed for arrays excited in the TM(01) mode.

  4. Roll and pitch independently tuned interconnected suspension: modelling and dynamic analysis

    NASA Astrophysics Data System (ADS)

    Xu, Guangzhong; Zhang, Nong; Roser, Holger M.

    2015-12-01

    In this paper, a roll and pitch independently tuned hydraulically interconnected passive suspension is presented. Due to decoupling of vibration modes and the improved lateral and longitudinal stability, the stiffness of individual suspension spring can be reduced for improving ride comfort and road grip. A generalised 14 degree-of-freedom nonlinear vehicle model with anti-roll bars is established to investigate the vehicle ride and handling dynamic responses. The nonlinear fluidic model of the hydraulically interconnected suspension is developed and integrated with the full vehicle model to investigate the anti-roll and anti-pitch characteristics. Time domain analysis of the vehicle model with the proposed suspension is conducted under different road excitations and steering/braking manoeuvres. The dynamic responses are compared with conventional suspensions to demonstrate the potential of enhanced ride and handling performance. The results illustrate the model-decoupling property of the hydraulically interconnected system. The anti-roll and anti-pitch performance could be tuned independently by the interconnected systems. With the improved anti-roll and anti-pitch characteristics, the bounce stiffness and ride damping can be optimised for better ride comfort and tyre grip.

  5. [Comparative analysis of changes in rats organisms exposed to microgravity and head-down suspension].

    PubMed

    Il'in, E A; Kaplanskiĭ, A S

    1998-01-01

    Comparative analysis of metabolic and structural shifts in rats following 14 days of microgravity aboard biosatellite Cosmos-2044 and their tail-suspended synchronous controls gave evidence that suspension-induced deprivation of hind limbs of support loading yields inherent to microgravity shifts the endocrine control of energy, plastic, and mineral metabolism. The conclusion has been drawn that tail-suspension can be used as a model of the microgravity effects on the musculoskeletal apparatus and the endocrine systems controlling metabolism in muscles and bones.

  6. Spacecraft Multiple Array Communication System Performance Analysis

    NASA Technical Reports Server (NTRS)

    Hwu, Shian U.; Desilva, Kanishka; Sham, Catherine C.

    2010-01-01

    The Communication Systems Simulation Laboratory (CSSL) at the NASA Johnson Space Center is tasked to perform spacecraft and ground network communication system simulations, design validation, and performance verification. The CSSL has developed simulation tools that model spacecraft communication systems and the space and ground environment in which the tools operate. In this paper, a spacecraft communication system with multiple arrays is simulated. Multiple array combined technique is used to increase the radio frequency coverage and data rate performance. The technique is to achieve phase coherence among the phased arrays to combine the signals at the targeting receiver constructively. There are many technical challenges in spacecraft integration with a high transmit power communication system. The array combining technique can improve the communication system data rate and coverage performances without increasing the system transmit power requirements. Example simulation results indicate significant performance improvement can be achieved with phase coherence implementation.

  7. Size analysis of suspension inhalation aerosols by inertial separation methods.

    PubMed

    Hallworth, G W; Andrews, U G

    1976-12-01

    The particle size distribution of beclomethasone dipropionate (BDP) aerosols delivered from pressurized metered dose suspension inhalers has been measured with three cascaded inertial separation instruments, the Casella Cascade Impactor, Multistage Liquid Impinger and Cascade Centripeter. Various methods for collecting the emitted aerosol before measurement have been examined. A bent glass tubular 'throat', used as a simulated oro-pharynx, collects 35-60% of the emitted dose by impingement of the wet spray cone in the throat. The aerosol passing through the throat has a similar but somewhat finer size distribution to that collected by firing directly into a large flask. The three cascaded instruments give similar results which in the Multistage Liquid Impinger also resemble those given by a salbutamol inhaler. The mass fraction (35-60%) emitted from the oral adaptor which is of a size capable of deep lung penetration ( less than 4 mum) is much higher than the fraction (10-16%) found in the lungs of dogs after inhalation of aerosol. The size distributions resemble those determined by microscopy and are expressed as aerodynamic sizes, thus showing that the particles approximate to unit density spheres. The performance of two simpler devices, Kirk's apparatus and the Harwell size selective air sampler are also assessed, the latter shows some promise for the simple evaluation of the respirable fraction of inhalation aerosols.

  8. Fabrication of plasmonic cavity arrays for SERS analysis.

    PubMed

    Li, Ning; Feng, Lei; Teng, Fei; Lu, Nan

    2017-05-05

    The plasmonic cavity arrays are ideal substrates for surface enhanced Raman scattering analysis because they can provide hot spots with large volume for analyte molecules. The large area increases the probability to make more analyte molecules on hot spots and leads to a high reproducibility. Therefore, to develop a simple method for creating cavity arrays is important. Herein, we demonstrate how to fabricate a V and W shape cavity arrays by a simple method based on self-assembly. Briefly, the V and W shape cavity arrays are respectively fabricated by taking KOH etching on a nanohole and a nanoring array patterned silicon (Si) slides. The nanohole array is generated by taking a reactive ion etching on a Si slide assembled with monolayer of polystyrene (PS) spheres. The nanoring array is generated by taking a reactive ion etching on a Si slide covered with a monolayer of octadecyltrichlorosilane before self-assembling PS spheres. Both plasmonic V and W cavity arrays can provide large hot area, which increases the probability for analyte molecules to deposit on the hot spots. Taking 4-Mercaptopyridine as analyte probe, the enhancement factor can reach 2.99 × 10(5) and 9.97 × 10(5) for plasmonic V cavity and W cavity array, respectively. The relative standard deviations of the plasmonic V and W cavity arrays are 6.5% and 10.2% respectively according to the spectra collected on 20 random spots.

  9. Rapid Screening of Complex Chemical Samples via Capillary Array Analysis

    SciTech Connect

    D. S. Anex; D. W. Neyer

    1998-11-01

    This report is a summary of the results of a two-year Laboratory-Directed Research and Development (LDRD) project that developed instrumentation and methods for capillary array analysis. During the course of this project, a new capillary array electrochromatography instrument was developed to perform eight simultaneous separations and provide complementary chromatographic information from each column on a single sample.

  10. Simultaneous detection of ochratoxin A and fumonisin B1 in cereal samples using an aptamer-photonic crystal encoded suspension array.

    PubMed

    Yue, Sun; Jie, Xu; Wei, Li; Bin, Cao; Dou Dou, Wang; Yi, Yang; QingXia, Lin; JianLin, Li; TieSong, Zheng

    2014-12-02

    A simple, new aptamer-photonic crystal encoded suspension array was designed to simultaneously quantify and qualify ochratoxin A(OTA) and fumonisin B1(FB1) in cereal samples. The aptamers of OTA and FB1 were immobilized on the surfaces of photonic crystals by chemical bonding. When the target mycotoxins appear in a sample, the fluorescence-labeled complementary DNA of the aptamer dissociates from their double DNA hybrid and results in an obvious decrease in fluorescence intensity of the microsphere. The difference value of fluorescent intensities for each kind of silica photonic crystal microsphere (SPCM) quantitatively conveys the concentration of mycotoxin, and the structure colors or reflectance peak positions of the SPCMs confirm the kind of mycotoxin detected. The reaction conditions including the immobilization method for aptamers, hybridization, and incubation conditions have been optimized. This developed method displayed a wide linear detection range (0.01-1 ng/mL for OTA and 0.001-1 ng/mL for FB1) and a low limit of detection (0.25 pg/mL for OTA and 0.16 pg/mL for FB1). The recovery rates in the spiked cereal samples ranged from 81.80% to 116.38% for OTA and 76.58%-114.79% for FB1. The positive detection results in the naturally contaminated cereal samples were in agreement with those of classic enzyme-linked immunosorbent assay (ELISA). This simple suspension array scheme displays a great application potential for the high throughput screen assay of mycotoxins.

  11. Geometric analysis and restitution of digital multispectral scanner data arrays

    NASA Technical Reports Server (NTRS)

    Baker, J. R.; Mikhail, E. M.

    1975-01-01

    An investigation was conducted to define causes of geometric defects within digital multispectral scanner (MSS) data arrays, to analyze the resulting geometric errors, and to investigate restitution methods to correct or reduce these errors. Geometric transformation relationships for scanned data, from which collinearity equations may be derived, served as the basis of parametric methods of analysis and restitution of MSS digital data arrays. The linearization of these collinearity equations is presented. Algorithms considered for use in analysis and restitution included the MSS collinearity equations, piecewise polynomials based on linearized collinearity equations, and nonparametric algorithms. A proposed system for geometric analysis and restitution of MSS digital data arrays was used to evaluate these algorithms, utilizing actual MSS data arrays. It was shown that collinearity equations and nonparametric algorithms both yield acceptable results, but nonparametric algorithms possess definite advantages in computational efficiency. Piecewise polynomials were found to yield inferior results.

  12. Economic analysis of the unified heliostat array

    NASA Astrophysics Data System (ADS)

    1980-11-01

    The array (UHA) is comprised of conventional two-axis heliostats mounted on a terraced south-facing wall of a single structure. The arrangement of heliostats on the array is chosen to eliminate or control the degree of inter-heliostat shading and blocking. The UHA was investigated as to cost and optical performance. Two heliostats, the Veda Industrial Heliostat (VIH) and the Repowering Helistat were investigated in conjunction with the UHA. The UHA is found to be a viable candidate for solar thermal central receiver applications. The UHA-VIH combination was shown to provide very high flux densities and to be suitable for high temperature applications in the 1000 K to 2000 K range. These temperatures were shown to be achieve even with very small (1 MWt) collector fields.

  13. Economic analysis of the unified heliostat array

    SciTech Connect

    Not Available

    1980-11-07

    The Unified Heliostat Array (UHA) is comprised of conventional two-axis heliostats mounted on a terraced south-facing wall of a single structure. The arrangement of heliostats on the array is chosen to eliminate or control the degree of inter-heliostat shading and blocking. The UHA was investifated as to cost and optical performance. Two heliostats, the Veda Industrial Heliostat (VIH) and the Repowering Heliostat were investigated in conjunction with the UHA. The UHA was found to be a viable candidate for solar thermal central receiver applications. The UHA-VIH combination was shown to provide very high flux densities and to be suitable for high temperature applications in the 1000/sup 0/K to 2000/sup 0/K range. These temperatures were shown to be achievable even with very small (1 MWt) collector fields.

  14. Analysis and performance of flat-plate solar collector arrays

    SciTech Connect

    Wang, X.A.; Wu, L.G. )

    1990-01-01

    A new discrete numerical model is proposed to calculate the flow and temperature distribution in solar collector arrays. The flow nonuniformity, the longitudinal heat conduction, and the buoyancy effect are all taken into account in the analysis. The numerical results of pressure and temperature distribution are found in agreement with the experimental results. It is found that the flow nonuniformity has detrimental effect on the thermal performance of collector array.

  15. Non-dimensionalised closed-form parametric analysis of semi-active vehicle suspensions using a quarter-car model

    NASA Astrophysics Data System (ADS)

    Ahmadian, Mehdi; Blanchard, Emmanuel

    2011-02-01

    This article provides a non-dimensionalised closed-form analysis of semi-active vehicle suspensions, using a quarter-car model. The derivation of the closed-form solutions for three indices that can be used for ride comfort, vehicle handling, and stability are presented based on non-dimensionalised suspension parameters. The behaviour of semi-active vehicle suspensions is evaluated using skyhook, groundhook, and hybrid control policies, and compared with passive suspensions. The relationship between vibration isolation, suspension deflection, and road holding is studied, using three performance indices based on the mean square of the sprung mass acceleration, rattle space, and tyre deflection, respectively. The results of the study indicate that the hybrid control policy yields significantly better comfort than a passive suspension, without reducing the road-holding quality or increasing the suspension displacement for typical passenger cars. The results also indicate that for typical passenger cars, the hybrid control policy results in a better compromise between comfort, road holding and suspension travel requirements than both the skyhook and groundhook control methods.

  16. Rapid Analysis, Self-Calibrating Array for Air Monitoring

    NASA Technical Reports Server (NTRS)

    Homer, Margie L.; Shevade, Abhijit V.; Lara, Liana; Huerta, Ramon; Vergara, Alexander; Muezzinoglua, Mehmet K.

    2012-01-01

    Human space missions have critical needs for monitoring and control for life support systems. These systems have monitoring needs that include feedback for closed loop processes and quality control for environmental factors. Sensors and monitoring technologies assure that the air environment and water supply for the astronaut crew habitat fall within acceptable limits, and that the life support system is functioning properly and efficiently. The longer the flight duration and the more distant the destination, the more critical it becomes to have carefully monitored and automated control systems for life support. Past experiments with the JPL ENose have demonstrated a lifetime of the sensor array, with the software, of around 18 months. The lifetime of the calibration, for some analytes, was as long as 24 months. We are working on a sensor array and new algorithms that will include sensor response time in the analysis. The preliminary array analysis for two analytes shows that the analysis time, of an event, can be dropped from 45 minutes to less than10 minutes and array training time can be cut substantially. We will describe the lifetime testing of an array and show lifetime data on individual sensors. This progress will lead to more rapid identification of analytes, and faster training time of the array.

  17. Performance Analysis of a NASA Integrated Network Array

    NASA Technical Reports Server (NTRS)

    Nessel, James A.

    2012-01-01

    The Space Communications and Navigation (SCaN) Program is planning to integrate its individual networks into a unified network which will function as a single entity to provide services to user missions. This integrated network architecture is expected to provide SCaN customers with the capabilities to seamlessly use any of the available SCaN assets to support their missions to efficiently meet the collective needs of Agency missions. One potential optimal application of these assets, based on this envisioned architecture, is that of arraying across existing networks to significantly enhance data rates and/or link availabilities. As such, this document provides an analysis of the transmit and receive performance of a proposed SCaN inter-network antenna array. From the study, it is determined that a fully integrated internetwork array does not provide any significant advantage over an intra-network array, one in which the assets of an individual network are arrayed for enhanced performance. Therefore, it is the recommendation of this study that NASA proceed with an arraying concept, with a fundamental focus on a network-centric arraying.

  18. Electrooptical Analysis of Microbial Cell Suspensions forDetermination of Antibiotic Resistance.

    PubMed

    Guliy, Olga I; Bunin, Victor D; Korzhenevich, Vyacheslav I; Volkov, Alexey A; Ignatov, Oleg V

    2016-12-01

    The effects of ampicillin; kanamycin, chloramphenicol, and tetracycline on electrophysical characteristics of cells of sensitive (ampicillin; kanamycin, chloramphenicol) and resistant (ampicillin; kanamycin, chloramphenicol, tetracycline) Escherichia coli strains were studied. Under the action of antibiotics sensitive and resistant E. coli strains acquire different electro-optical properties. Changes in suspension-orientational spectra, that are observed under the action of ampicillin; kanamycin, chloramphenicol, and tetracycline can be used in determination of antibiotic resistance of the studied bacterial strains. In our opinion, the methods of microbial suspension electro-optical analysis can be used in microbiology, mеdicinе, veterinary, and are an effective tool for solving the problems connected with determination of microbial cell antibiotic resistance.

  19. Callogenesis and cell suspension establishment of tropical highland blackberry (Rubus adenotrichos Schltdl.) and its microscopic analysis.

    PubMed

    Schmidt-Durán, Alexander; Alvarado-Ulloa, Carlos; Chacón-Cerdas, Randall; Alvarado-Marchena, Luis Fernando; Flores-Mora, Dora

    2016-01-01

    Blackberries are fruits produced worldwide, with 25 % of their production centered in Mexico, Central and South America. Tropical highland blackberry is a fruit that can potentially enhance human health, due to their high content in phenolic compounds, which include anthocyanins, phenolic acids, tannins (gallotannins and elagitannins) and flavonoids. Therefore, the overall aim of this study is the development of a callus induction protocol, the establishment of blackberry cell suspensions (Rubus adenotrichos Schltdl.) and their cell analysis through optical microscopy and TEM, for the potential production of phenolic compounds. In order to produce callogenesis, segments of blackberry leaves were disinfected and placed in different concentrations of 2,4-D and the control media (0; 0.5; 1.0; 1.5; 2.0; 2.5 and 3.0 mg/l of 2,4-D); obtaining the higher size of calli in the medium with 1.5 mg/l of 2,4-D. After this determination, and for this specific treatment, a growth curve was performed through the use of fresh and dry weight parameters, in order to identify each of the growth stages. Furthermore, the calli obtained from the 1.5 mg/l of 2,4-D treatment were placed in two different culture media (MS and MS supplemented with 1.5 mg/l of 2,4-D) in order to establish the cell suspensions and the growth curve. To the best treatment, the total polyphenols were also quantified. It was determined that the MS medium is ideal for the growth and disintegration of the cell suspensions, obtaining 0.0256 mg of gallic acid/g of fresh sample. Finally, a cell callus and cell suspension analysis was performed through OM and TEM, evidencing a higher hystological differentiation in the calli, as well as the observation of antioxidant storage in the plastids.

  20. International Space Station 2A Array Modal Analysis

    NASA Technical Reports Server (NTRS)

    Laible, Michael; Fitzpatrick, Kristin; Grygier, Michael

    2012-01-01

    On December 9th 2009, the International Space Station (ISS) 2A solar array mast experienced prolonged longeron shadowing during a Soyuz undocking. Analytical reconstruction of induced thermal and dynamic structural loads showed an exceedance of the mast buckling limit. Possible structural damage to the solar array mast could have occurred during this event. A Low fidelity video survey of the 2A mast showed no obvious damage of the mast longerons or battens. The decision was made to conduct an on-orbit dynamic test of the 2A array on December 18th, 2009. The test included thruster pluming on the array while photogrammetry data was recorded. The test was similar to other Dedicated Thruster Firings (DTFs) that were performed to measure structural frequency and damping of a solar array. Results of the DTF indicated lower frequency mast modes than model predictions, thus leading to speculation of mast damage. A detailed nonlinear analysis was performed on the 2A array model to assess possible solutions to modal differences. The setup of the parametric nonlinear trade study included the use of a detailed array model and the reduced mass and stiffness matrices of the entire ISS being applied to the array interface. The study revealed that the array attachment structure is nonlinear and thus was the source of error in the model prediction of mast modes. In addition, a detailed study was performed to determine mast mode sensitivity to mast longeron damage. This sensitivity study was performed to assess if the ISS program has sufficient instrumentation for mast damage detection.

  1. Stability of binary and ternary model oil-field particle suspensions: a multivariate analysis approach.

    PubMed

    Dudásová, Dorota; Rune Flåten, Geir; Sjöblom, Johan; Øye, Gisle

    2009-09-15

    The transmission profiles of one- to three-component particle suspension mixtures were analyzed by multivariate methods such as principal component analysis (PCA) and partial least-squares regression (PLS). The particles mimic the solids present in oil-field-produced water. Kaolin and silica represent solids of reservoir origin, whereas FeS is the product of bacterial metabolic activities, and Fe(3)O(4) corrosion product (e.g., from pipelines). All particles were coated with crude oil surface active components to imitate particles in real systems. The effects of different variables (concentration, temperature, and coating) on the suspension stability were studied with Turbiscan LAb(Expert). The transmission profiles over 75 min represent the overall water quality, while the transmission during the first 15.5 min gives information for suspension behavior during a representative time period for the hold time in the separator. The behavior of the mixed particle suspensions was compared to that of the single particle suspensions and models describing the systems were built. The findings are summarized as follows: silica seems to dominate the mixture properties in the binary suspensions toward enhanced separation. For 75 min, temperature and concentration are the most significant, while for 15.5 min, concentration is the only significant variable. Models for prediction of transmission spectra from run parameters as well as particle type from transmission profiles (inverse calibration) give a reasonable description of the relationships. In ternary particle mixtures, silica is not dominant and for 75 min, the significant variables for mixture (temperature and coating) are more similar to single kaolin and FeS/Fe(3)O(4). On the other hand, for 15.5 min, the coating is the most significant and this is similar to one for silica (at 15.5 min). The model for prediction of transmission spectra from run parameters gives good estimates of the transmission profiles. Although the

  2. EzArray: A web-based highly automated Affymetrix expression array data management and analysis system

    PubMed Central

    Zhu, Yuerong; Zhu, Yuelin; Xu, Wei

    2008-01-01

    Background Though microarray experiments are very popular in life science research, managing and analyzing microarray data are still challenging tasks for many biologists. Most microarray programs require users to have sophisticated knowledge of mathematics, statistics and computer skills for usage. With accumulating microarray data deposited in public databases, easy-to-use programs to re-analyze previously published microarray data are in high demand. Results EzArray is a web-based Affymetrix expression array data management and analysis system for researchers who need to organize microarray data efficiently and get data analyzed instantly. EzArray organizes microarray data into projects that can be analyzed online with predefined or custom procedures. EzArray performs data preprocessing and detection of differentially expressed genes with statistical methods. All analysis procedures are optimized and highly automated so that even novice users with limited pre-knowledge of microarray data analysis can complete initial analysis quickly. Since all input files, analysis parameters, and executed scripts can be downloaded, EzArray provides maximum reproducibility for each analysis. In addition, EzArray integrates with Gene Expression Omnibus (GEO) and allows instantaneous re-analysis of published array data. Conclusion EzArray is a novel Affymetrix expression array data analysis and sharing system. EzArray provides easy-to-use tools for re-analyzing published microarray data and will help both novice and experienced users perform initial analysis of their microarray data from the location of data storage. We believe EzArray will be a useful system for facilities with microarray services and laboratories with multiple members involved in microarray data analysis. EzArray is freely available from . PMID:18218103

  3. Analysis of Dynamic Stiffness Effect of Primary Suspension Helical Springs on Railway Vehicle Vibration

    NASA Astrophysics Data System (ADS)

    Sun, W.; Thompson, D. J.; Zhou, J.; Gong, D.

    2016-09-01

    Helical springs within the primary suspension are critical components for isolating the whole vehicle system from vibration generated at the wheel/rail contact. As train speeds increase, the frequency region of excitation becomes larger, and a simplified static stiffness can no longer represent the real stiffness property in a vehicle dynamic model. Coil springs in particular exhibit strong internal resonances, which lead to high vibration amplitudes within the spring itself as well as degradation of the vibration isolation. In this paper, the dynamic stiffness matrix method is used to determine the dynamic stiffness of a helical spring from a vehicle primary suspension. Results are confirmed with a finite element analysis. Then the spring dynamic stiffness is included within a vehicle-track coupled dynamic model of a high speed train and the effect of the dynamic stiffening of the spring on the vehicle vibration is investigated. It is shown that, for frequencies above about 50 Hz, the dynamic stiffness of the helical spring changes sharply. Due to this effect, the vibration transmissibility increases considerably which results in poor vibration isolation of the primary suspension. Introducing a rubber layer in series with the coil spring can attenuate this effect.

  4. Galloping comparative analysis for transient main cables of suspension bridge during construction

    NASA Astrophysics Data System (ADS)

    Li, Shengli; Peng, Gang; Zhang, Haiting; Chen, Huai

    2011-04-01

    The cross-sectional shapes of two construction projects for the transient main cables are non-circular cross-sections during construction of the long-span suspension bridge, so the transient main cables can experience galloping instabilities. The galloping coefficients of the several representative cases of two construction projects for the transient main cables without wind-resistant measures for the long-span suspension bridge were investigated for the first time by means of the CFD method, referring to an erecting suspension bridge. Results show that for the project 1, at the early stages of the main cables construction, the galloping instabilities can occur, but at the later stages of that, the galloping instabilities cannot occur. For the project 2, there exists a lot of wind attack angles whose galloping coefficients are less than 0 at the whole construction stages. From the perspective for galloping instability the project 1 is better 2.Through the analysis and comparison the galloping performance of two kinds of construction projects for the transient main cables, the advantage and disadvantage for two construction projects is explained theoretically from the perspective for whether can result in the galloping instability.

  5. Studying Mixing in Non-Newtonian Blue Maize Flour Suspensions Using Color Analysis

    PubMed Central

    Trujillo-de Santiago, Grissel; Rojas-de Gante, Cecilia; García-Lara, Silverio; Ballescá-Estrada, Adriana; Alvarez, Mario Moisés

    2014-01-01

    Background Non-Newtonian fluids occur in many relevant flow and mixing scenarios at the lab and industrial scale. The addition of acid or basic solutions to a non-Newtonian fluid is not an infrequent operation, particularly in Biotechnology applications where the pH of Non-Newtonian culture broths is usually regulated using this strategy. Methodology and Findings We conducted mixing experiments in agitated vessels using Non-Newtonian blue maize flour suspensions. Acid or basic pulses were injected to reveal mixing patterns and flow structures and to follow their time evolution. No foreign pH indicator was used as blue maize flours naturally contain anthocyanins that act as a native, wide spectrum, pH indicator. We describe a novel method to quantitate mixedness and mixing evolution through Dynamic Color Analysis (DCA) in this system. Color readings corresponding to different times and locations within the mixing vessel were taken with a digital camera (or a colorimeter) and translated to the CIELab scale of colors. We use distances in the Lab space, a 3D color space, between a particular mixing state and the final mixing point to characterize segregation/mixing in the system. Conclusion and Relevance Blue maize suspensions represent an adequate and flexible model to study mixing (and fluid mechanics in general) in Non-Newtonian suspensions using acid/base tracer injections. Simple strategies based on the evaluation of color distances in the CIELab space (or other scales such as HSB) can be adapted to characterize mixedness and mixing evolution in experiments using blue maize suspensions. PMID:25401332

  6. On the Statics for Micro-Array Data Analysis

    NASA Astrophysics Data System (ADS)

    Urushibara, Tomoko; Akasaka, Shizu; Ito, Makiko; Suzuki, Tomonori; Miyazaki, Satoru

    2010-01-01

    Recently after human genome sequence has been determined almost perfectly, more and more researchers have been studying genes in detail. Therefore, we are sure that accumulated gene information for human will be getting more important in the near future to develop customized medicine and to make gene interactions clear. Among plenty of information, micro array might be one of the most important analysis method for genes because it is the technique that can get big amount of the gene expressions data from one time experiment and also can be used for DNA isolation. To get the novel knowledge from micro array data, we need to enrich statistical tools for its data analysis. So far, many mathematical theories and definition have been proposing. However, many of those proposals are tested with strict conditions or customized to data for specific species. In this paper, we reviewed existing typical statistical methods for micro array analysis and discussed the repeatability of the analysis, construction the guideline with more general procedure. First we analyzed the micro array data for TG rats, with statistical methods of family-wise error rate (FWER) control approach and False Discovery Rate (FDR) control approach. As existing report, no significantly different gene could be detected with FWER control approach. On the other hand, we could find several genes significantly with FDR control approach even q=0.5. To find out the reliability of FDR control approach with micro array conditions, we have analyzed 2 more pieces of data from Gene Expression Omnibus (GEO) public database on the web site with SAM in addition to FWER and FDR control approaches. We could find a certain number of significantly different genes with BH method and SAM in the case of q=0.05. However, we have to note that the number and kinds of detected genes are different when we compare our result with the one from the published paper. Even if the same approach is used to analyze the same micro array

  7. Analysis and simulation of a magnetic bearing suspension system for a laboratory model annular momentum control device

    NASA Technical Reports Server (NTRS)

    Groom, N. J.; Woolley, C. T.; Joshi, S. M.

    1981-01-01

    A linear analysis and the results of a nonlinear simulation of a magnetic bearing suspension system which uses permanent magnet flux biasing are presented. The magnetic bearing suspension is part of a 4068 N-m-s (3000 lb-ft-sec) laboratory model annular momentum control device (AMCD). The simulation includes rigid body rim dynamics, linear and nonlinear axial actuators, linear radial actuators, axial and radial rim warp, and power supply and power driver current limits.

  8. Independent Component Analysis of Nanomechanical Responses of Cantilever Arrays

    SciTech Connect

    Archibald, Richard K; Datskos, Panos G; Noid, Don W; Lavrik, Nickolay V

    2007-01-01

    The ability to detect and identify chemical and biological elements in air or liquid environments is of far reaching importance. Performing this task using technology that minimally impacts the perceived environment is the ultimate goal. The development of functionalized cantilever arrays with nanomechanical sensing is an important step towards this ambition. This report couples the feature extraction abilities of Independent Component Analysis (ICA) and the classification techniques of neural networks to analyze the signals produced by microcantilever-array-based nanomechanical sensors. The unique capabilities of this analysis unleash the potential of this sensing technology to accurately determine the identities and concentrations of the components of chemical mixtures. Furthermore, it is demonstrated that the knowledge of how the sensor array reacts to individual analytes in isolation is sufficient information to decode mixtures of analytes - a substantial benefit, significantly increasing the analytical utility of these sensing devices.

  9. Neural network based analysis for chemical sensor arrays

    SciTech Connect

    Hashem, S.; Keller, P.E.; Kouzes, R.T.; Kangas, L.J.

    1995-04-01

    Compact, portable systems capable of quickly identifying contaminants in the field are of great importance when monitoring the environment. In this paper, we examine the effectiveness of using artificial neural networks for real-time data analysis of a sensor array. Analyzing the sensor data in parallel may allow for rapid identification of contaminants in the field without requiring highly selective individual sensors. We use a prototype sensor array which consists of nine tin-oxide Taguchi-type sensors, a temperature sensor, and a humidity sensor. We illustrate that by using neural network based analysis of the sensor data, the selectivity of the sensor array may be significantly improved, especially when some (or all) the sensors are not highly selective.

  10. Analysis of an off road 4WD vehicle's suspension system modification - Case study of aftermarket suspension lift and modification of wheel track size

    NASA Astrophysics Data System (ADS)

    Ross, J.; Hazrat, M. A.; Rasul, M. G.

    2016-07-01

    In this research, a four wheel drive (4WD) suspension of a vehicle has been modified by increasing the ride height to investigate stability and cornering potential of the vehicle through load transfer and variation of roll angle. Further investigation has been conducted to observe the characteristics which are deemed desirable for off road application but detrimental to the on road application. The Constant Radius Cornering Test (CRCT) was chosen as a base method for experimental investigation to observe the effect of the suspension modifications. The test was carried out by undertaking a known radius and cambered corner at a constant speed. For this test, the acceleration and gyroscopic data were measured to check and compare the accuracy of the analysis performed by OptimumDynamics model. The tests were conducted by means of negotiating the curve at the speed of 80 km/h and it was gradually achieved to allow a good consensus of the amount of body roll the vehicle experienced. Using a surveyor's wheel, the radius of the corner was estimated as 160 m and using the gyroscopic sensor, the corner camber was measured at 4 degrees. While comparing the experimental results with the simulation results, the experimental constraints led to higher values than those of the analytical results. The total load transfer reduced by 2.9% with the increased track size. It has been observed that the dynamic load transfer component is lesser than the standard suspension with the aftermarket suspension lift and the upgraded anti-roll bar (ARB). With the simulation of the fitment of the other modifications aimed to improve the characteristics of the raised vehicle, the vehicle showed a reduced tendency towards roll angle due to the stiffened anti-roll bar and the maximum increased wheel track demonstrated reduced lateral load transfer and body roll. Even with these modifications however, the decrease in load transfer is minimal in comparison to what was expected.

  11. Thermoelastic analysis of solar cell arrays and their material properties

    NASA Technical Reports Server (NTRS)

    Salama, M. A.; Rowe, W. M.; Yasui, R. K.

    1973-01-01

    A thermoelastic stress analysis procedure is reported for predicting the thermally induced stresses and failures in silicon solar cell arrays. A prerequisite for the analysis is the characterization of the temperature-dependent thermal and mechanical properties of the solar cell materials. Extensive material property testing was carried out in the temperature range -200 to +200 C for the filter glass, P- and N-type silicon, interconnector metals, solder, and several candidate silicone rubber adhesives. The analysis procedure is applied to several solar cell array design configurations. Results of the analysis indicate the optimum design configuration, with respect to compatible materials, effect of the solder coating, and effect of the interconnector geometry. Good agreement was found between results of the analysis and the test program.

  12. Off-road motorbike performance analysis using a rear semi-active suspension

    NASA Astrophysics Data System (ADS)

    Lozoya-Santos, Jorge de J.; Cervantes-Muñoz, Damián.; Ramírez Mendoza, Ricardo

    2015-04-01

    The topic of this paper is the analysis of a control system for a semi active rear suspension in an off-road 2-wheel vehicle. Several control methods are studied, as well as the recently proposed Frequency Estimation Based (FEB) algorithm. The test motorcycle dynamics, as well as the passive, semi active, and the algorithm controlled shock absorber models are loaded into BikeSim, a professional two-wheeled vehicle simulation software, and tested in several road conditions. The results show a detailed comparison of the theoretical performance of the different control approaches in a novel environment for semi active dampers.

  13. Digital interactive image analysis by array processing

    NASA Technical Reports Server (NTRS)

    Sabels, B. E.; Jennings, J. D.

    1973-01-01

    An attempt is made to draw a parallel between the existing geophysical data processing service industries and the emerging earth resources data support requirements. The relationship of seismic data analysis to ERTS data analysis is natural because in either case data is digitally recorded in the same format, resulting from remotely sensed energy which has been reflected, attenuated, shifted and degraded on its path from the source to the receiver. In the seismic case the energy is acoustic, ranging in frequencies from 10 to 75 cps, for which the lithosphere appears semi-transparent. In earth survey remote sensing through the atmosphere, visible and infrared frequency bands are being used. Yet the hardware and software required to process the magnetically recorded data from the two realms of inquiry are identical and similar, respectively. The resulting data products are similar.

  14. Modelling and characteristic analysis of tri-axle trucks with hydraulically interconnected suspensions

    NASA Astrophysics Data System (ADS)

    Ding, Fei; Han, Xu; Luo, Zhen; Zhang, Nong

    2012-12-01

    In this paper, a new hydraulically interconnected suspension (HIS) system is proposed for the implementation of a resistance control for the pitch and bounce modes of tri-axle heavy trucks. A lumped-mass half-truck model is established using the free-body diagram method. The equations of motion of a mechanical and hydraulic coupled system are developed by incorporating the hydraulic strut forces into the mechanical subsystem as externally applied forces. The transfer matrix method (TMM) is used to evaluate the impedance matrix of the hydraulic subsystem consisting of models of fluid pipes, damper valves, accumulators, and three-way junctions. The TMM is further applied to find the quantitative relationships between the hydraulic strut forces and boundary flow of the mechanical-fluid interactive subsystem. The modal analysis method is employed to perform the vibration analysis between the trucks with the conventional suspension and the proposed HIS. Comparison analysis focuses on free vibration with identified eigenvalues and eigenvectors, isolation vibration capacity, and force vibration in terms of the power spectrum density responses. The obtained results show the effectiveness of the proposed HIS system in reducing the pitch motion of sprung mass and simultaneously maintaining the ride comfort. The pitch stiffness is increased while the bounce stiffness is slightly softened. The peak values of sprung mass and wheel hop motions are greatly reduced, and the vibration decay rate of sprung mass is also significantly increased.

  15. Analysis of Enriched Uranyl Nitrate in Nested Annular Tank Array

    SciTech Connect

    John D. Bess; James D. Cleaver

    2009-06-01

    Two series of experiments were performed at the Rocky Flats Critical Mass Laboratory during the 1980s using highly enriched (93%) uranyl nitrate solution in annular tanks. [1, 2] Tanks were of typical sizes found in nuclear production plants. Experiments looked at tanks of varying radii in a co-located set of nested tanks, a 1 by 2 array, and a 1 by 3 array. The co-located set of tanks had been analyzed previously [3] as a benchmark for inclusion within the International Handbook of Evaluated Criticality Safety Benchmark Experiments. [4] The current study represents the benchmark analysis of the 1 by 3 array of a series of nested annular tanks. Of the seventeen configurations performed in this set of experiments, twelve were evaluated and nine were judged as acceptable benchmarks.

  16. Study on failure analysis of array chip components in IRFPA

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaonan; He, Yingjie; Li, Jinping

    2016-10-01

    Infrared focal plane array detector has advantages of strong anti-interference ability and high sensitivity. Its size, weight and power dissipation has been noticeably decreased compared to the conventional infrared imaging system. With the development of the detector manufacture technology and the cost reduction, IRFPA detector has been widely used in the military and commercial fields. Due to the restricting of array chip manufacturing process and material defects, the fault phenomenon such as cracking, bad pixel and abnormal output was showed during the test, which restricts the performance of the infrared detector imaging system, and these effects are gradually intensified with the expanding of the focal plane array size and the shrinking of the pixel size. Based on the analysis of the test results for the infrared detector array chip components, the fault phenomenon was classified. The main cause of the chip component failure is chip cracking, bad pixel and abnormal output. The reason of the failure has been analyzed deeply. According to analyze the mechanism of the failure, a series of measures which contain filtrating materials and optimizing the manufacturing process of array chip components were used to improve the performance of the chip components and the test pass rate, which is used to meet the needs of the detector performance.

  17. Analysis of Camera Arrays Applicable to the Internet of Things

    PubMed Central

    Yang, Jiachen; Xu, Ru; Lv, Zhihan; Song, Houbing

    2016-01-01

    The Internet of Things is built based on various sensors and networks. Sensors for stereo capture are essential for acquiring information and have been applied in different fields. In this paper, we focus on the camera modeling and analysis, which is very important for stereo display and helps with viewing. We model two kinds of cameras, a parallel and a converged one, and analyze the difference between them in vertical and horizontal parallax. Even though different kinds of camera arrays are used in various applications and analyzed in the research work, there are few discussions on the comparison of them. Therefore, we make a detailed analysis about their performance over different shooting distances. From our analysis, we find that the threshold of shooting distance for converged cameras is 7 m. In addition, we design a camera array in our work that can be used as a parallel camera array, as well as a converged camera array and take some images and videos with it to identify the threshold. PMID:27011189

  18. Analysis of Camera Arrays Applicable to the Internet of Things.

    PubMed

    Yang, Jiachen; Xu, Ru; Lv, Zhihan; Song, Houbing

    2016-03-22

    The Internet of Things is built based on various sensors and networks. Sensors for stereo capture are essential for acquiring information and have been applied in different fields. In this paper, we focus on the camera modeling and analysis, which is very important for stereo display and helps with viewing. We model two kinds of cameras, a parallel and a converged one, and analyze the difference between them in vertical and horizontal parallax. Even though different kinds of camera arrays are used in various applications and analyzed in the research work, there are few discussions on the comparison of them. Therefore, we make a detailed analysis about their performance over different shooting distances. From our analysis, we find that the threshold of shooting distance for converged cameras is 7 m. In addition, we design a camera array in our work that can be used as a parallel camera array, as well as a converged camera array and take some images and videos with it to identify the threshold.

  19. A Darker Shade of Gray: A Year-End Analysis of Discipline and Suspension Data.

    ERIC Educational Resources Information Center

    Nichols, Joe D.; Ludwin, William G.; Iadicola, Peter

    1999-01-01

    Studied school suspensions in a large metropolitan school district in which minority students were overrepresented in discipline reports. Study of suspensions at five middle schools and high schools shows inconsistent reporting of disciplinary and suspension data, making it difficult to quantify racial and class bias that appears to exist. (SLD)

  20. WebArray: an online platform for microarray data analysis

    PubMed Central

    Xia, Xiaoqin; McClelland, Michael; Wang, Yipeng

    2005-01-01

    Background Many cutting-edge microarray analysis tools and algorithms, including commonly used limma and affy packages in Bioconductor, need sophisticated knowledge of mathematics, statistics and computer skills for implementation. Commercially available software can provide a user-friendly interface at considerable cost. To facilitate the use of these tools for microarray data analysis on an open platform we developed an online microarray data analysis platform, WebArray, for bench biologists to utilize these tools to explore data from single/dual color microarray experiments. Results The currently implemented functions were based on limma and affy package from Bioconductor, the spacings LOESS histogram (SPLOSH) method, PCA-assisted normalization method and genome mapping method. WebArray incorporates these packages and provides a user-friendly interface for accessing a wide range of key functions of limma and others, such as spot quality weight, background correction, graphical plotting, normalization, linear modeling, empirical bayes statistical analysis, false discovery rate (FDR) estimation, chromosomal mapping for genome comparison. Conclusion WebArray offers a convenient platform for bench biologists to access several cutting-edge microarray data analysis tools. The website is freely available at . It runs on a Linux server with Apache and MySQL. PMID:16371165

  1. [Determination of Azospirillum Brasilense Cells With Bacteriophages via Electrooptical Analysis of Microbial Suspensions].

    PubMed

    Gulii, O I; Karavayeva, O A; Pavlii, S A; Sokolov, O I; Bunin, V D; Ignatov, O V

    2015-01-01

    The dependence-of changes in the electrooptical properties of Azospirillum brasilense cell suspension Sp7 during interaction with bacteriophage ΦAb-Sp7 on the number and time of interactions was studied. Incubation of cells with bacteriophage significantly changed the electrooptical signal within one minute. The selective effect of bacteriophage ΦAb on 18 strains of bacteria of the genus Azospirillum was studied: A. amazonense Ami4, A. brasilense Sp7, Cd, Sp107, Sp245, Jm6B2, Brl4, KR77, S17, S27, SR55, SR75, A. halopraeferans Au4, A. irakense KBC1, K A3, A. lipoferum Sp59b, SR65 and RG20a. We determined the limit of reliable determination of microbial cells infected with bacteriophage: - 10(4) cells/mL. The presence of foreign cell cultures of E. coli B-878 and E. coli XL-1 did not complicate the detection of A brasilense Sp7 cells with the use of bacteriophage ΦAb-Sp7. The results demonstrated that bacteriophage (ΦAb-Sp7 can be used for the detection of Azospirillum microbial cells via t electrooptical analysis of cell suspensions.

  2. Raman spectroscopy for the process analysis of the manufacturing of a suspension metered dose inhaler.

    PubMed

    Butz, James; de la Cruz, Luis; DiTonno, Jason; DeBoyace, Kevin; Ewing, Gary; Donovan, Brent; Medendorp, Joseph

    2011-04-05

    The purpose of this research was to demonstrate the utility of Raman spectroscopy for process analysis of a suspension metered dose inhaler manufacturing process. Chemometric models were constructed for the quantification of ethanol and active pharmaceutical ingredient such that both could be monitored in real-time during the compounding and filling operations via tank measurements and recirculation line flow-cell measurements. Different spectral preprocessing techniques were used to delineate the effects of mixing speed and temperature changes from actual concentration effects. Raman spectroscopy offers advantages in time savings and quality of information over the standard methods of analysis for respiratory formulations, such as a drug content assay via HPLC and ethanol testing via GC. The successful implementation of this work will allow formulation scientists to quantitatively assess both the formulation (e.g., the concentration of active pharmaceutical ingredient (API) and ethanol), as well as the manufacturing process (e.g., determination of mixing endpoints) in real-time.

  3. Data analysis for the CHARA Array CLIMB beam combiner

    NASA Astrophysics Data System (ADS)

    ten Brummelaar, Theo A.; Sturmann, Judit; McAlister, Harold A.; Sturmann, Laszlo; Turner, Nils H.; Farrington, Chris D.; Schaefer, Gail; Goldfinger, P. J.; Kloppenborg, Brian

    2012-07-01

    The CHARA Array is a six telescope optical/IR interferometer run by the Center for High Angular Resolution Astronomy of Georgia State University and is located at Mount Wilson Observatory just to the north of Los Angeles California. The CHARA Array has the largest operational baselines in the world and has been in regular use for scientific observations since 2004. Our most sensitive beam combiner capable of measuring closure phases is the CLassic Interferometry with Multiple Baselines beam combiner known as CLIMB. In this paper we discuss the design and layout of CLIMB with a particular focus on the data analysis methodology. This analysis is presented in a very general form and will have applications in many other beam combiners. We also present examples of on sky data showing the precision and stability of both amplitude and closure phase measurements.

  4. Single cell array impedance analysis in a microfluidic device

    NASA Astrophysics Data System (ADS)

    Altinagac, Emre; Taskin, Selen; Kizil, Huseyin

    2016-10-01

    Impedance analysis of single cells is presented in this paper. Following the separation of a target cell type by dielectrophoresis in our previous work, this paper focuses on capturing the cells as a single array and performing impedance analysis to point out the signature difference between each cell type. Lab-on-a-chip devices having a titanium interdigitated electrode layer on a glass substrate and a PDMS microchannel are fabricated to capture each cell in a single form and perform impedance analysis. HCT116 (homosapiens colon colorectal carcin) and HEK293 (human embryonic kidney) cells are used in our experiments.

  5. Array-Pattern-Match Compiler for Opportunistic Data Analysis

    NASA Technical Reports Server (NTRS)

    James, Mark

    2006-01-01

    A computer program has been written to facilitate real-time sifting of scientific data as they are acquired to find data patterns deemed to warrant further analysis. The patterns in question are of a type denoted array patterns, which are specified by nested parenthetical expressions. [One example of an array pattern is ((>3) 0 (not=1)): this pattern matches a vector of at least three elements, the first of which exceeds 3, the second of which is 0, and the third of which does not equal 1.] This program accepts a high-level description of a static array pattern and compiles a highly optimal and compact other program to determine whether any given instance of any data array matches that pattern. The compiler implemented by this program is independent of the target language, so that as new languages are used to write code that processes scientific data, they can easily be adapted to this compiler. This program runs on a variety of different computing platforms. It must be run in conjunction with any one of a number of Lisp compilers that are available commercially or as shareware.

  6. Improvements in analysis techniques for segmented mirror arrays

    NASA Astrophysics Data System (ADS)

    Michels, Gregory J.; Genberg, Victor L.; Bisson, Gary R.

    2016-08-01

    The employment of actively controlled segmented mirror architectures has become increasingly common in the development of current astronomical telescopes. Optomechanical analysis of such hardware presents unique issues compared to that of monolithic mirror designs. The work presented here is a review of current capabilities and improvements in the methodology of the analysis of mechanically induced surface deformation of such systems. The recent improvements include capability to differentiate surface deformation at the array and segment level. This differentiation allowing surface deformation analysis at each individual segment level offers useful insight into the mechanical behavior of the segments that is unavailable by analysis solely at the parent array level. In addition, capability to characterize the full displacement vector deformation of collections of points allows analysis of mechanical disturbance predictions of assembly interfaces relative to other assembly interfaces. This capability, called racking analysis, allows engineers to develop designs for segment-to-segment phasing performance in assembly integration, 0g release, and thermal stability of operation. The performance predicted by racking has the advantage of being comparable to the measurements used in assembly of hardware. Approaches to all of the above issues are presented and demonstrated by example with SigFit, a commercially available tool integrating mechanical analysis with optical analysis.

  7. Light-generated oligonucleotide arrays for rapid DNA sequence analysis.

    PubMed Central

    Pease, A C; Solas, D; Sullivan, E J; Cronin, M T; Holmes, C P; Fodor, S P

    1994-01-01

    In many areas of molecular biology there is a need to rapidly extract and analyze genetic information; however, current technologies for DNA sequence analysis are slow and labor intensive. We report here how modern photolithographic techniques can be used to facilitate sequence analysis by generating miniaturized arrays of densely packed oligonucleotide probes. These probe arrays, or DNA chips, can then be applied to parallel DNA hybridization analysis, directly yielding sequence information. In a preliminary experiment, a 1.28 x 1.28 cm array of 256 different octanucleotides was produced in 16 chemical reaction cycles, requiring 4 hr to complete. The hybridization pattern of fluorescently labeled oligonucleotide targets was then detected by epifluorescence microscopy. The fluorescence signals from complementary probes were 5-35 times stronger than those with single or double base-pair hybridization mismatches, demonstrating specificity in the identification of complementary sequences. This method should prove to be a powerful tool for rapid investigations in human genetics and diagnostics, pathogen detection, and DNA molecular recognition. Images PMID:8197176

  8. Guidelines for Optimisation of a Multiplex Oligonucleotide Ligation-PCR for Characterisation of Microbial Pathogens in a Microsphere Suspension Array

    PubMed Central

    Wuyts, Véronique; Roosens, Nancy H. C.; Marchal, Kathleen; De Keersmaecker, Sigrid C. J.

    2015-01-01

    With multiplex oligonucleotide ligation-PCR (MOL-PCR) different molecular markers can be simultaneously analysed in a single assay and high levels of multiplexing can be achieved in high-throughput format. As such, MOL-PCR is a convenient solution for microbial detection and identification assays where many markers should be analysed, including for routine further characterisation of an identified microbial pathogenic isolate. For an assay aimed at routine use, optimisation in terms of differentiation between positive and negative results and of cost and effort is indispensable. As MOL-PCR includes a multiplex ligation step, followed by a singleplex PCR and analysis with microspheres on a Luminex device, several parameters are accessible for optimisation. Although MOL-PCR performance may be influenced by the markers used in the assay and the targeted bacterial species, evaluation of the method of DNA isolation, the probe concentration, the amount of microspheres, and the concentration of reporter dye is advisable in the development of any MOL-PCR assay. Therefore, we here describe our observations made during the optimisation of a 20-plex MOL-PCR assay for subtyping of Salmonella Typhimurium with the aim to provide a possible workflow as guidance for the development and optimisation of a MOL-PCR assay for the characterisation of other microbial pathogens. PMID:25705689

  9. Morphology Analysis of Si Island Arrays on Si(001)

    PubMed Central

    2010-01-01

    The formation of nanometer-scale islands is an important issue for bottom-up-based schemes in novel electronic, optoelectronic and magnetoelectronic devices technology. In this work, we present a detailed atomic force microscopy analysis of Si island arrays grown by molecular beam epitaxy. Recent reports have shown that self-assembled distributions of fourfold pyramid-like islands develop in 5-nm thick Si layers grown at substrate temperatures of 650 and 750°C on HF-prepared Si(001) substrates. Looking for wielding control and understanding the phenomena involved in this surface nanostructuring, we develop and apply a formalism that allows for processing large area AFM topographic images in a shot, obtaining surface orientation maps with specific information on facets population. The procedure reveals some noticeable features of these Si island arrays, e.g. a clear anisotropy of the in-plane local slope distributions. Total island volume analysis also indicates mass transport from the substrate surface to the 3D islands, a process presumably related to the presence of trenches around some of the pyramids. Results are discussed within the framework of similar island arrays in homoepitaxial and heteroepitaxial semiconductor systems. PMID:21170139

  10. Array-CGH analysis of cutaneous anaplastic large cell lymphoma.

    PubMed

    Szuhai, K; van Doorn, R; Tensen, C P; Van Kester

    2013-01-01

    This chapter describes a study in which the pattern of numerical chromosomal alterations in cutaneous anaplastic large cell lymphoma (C-ALCL) tumor samples was defined using array-based comparative genomic hybridization (CGH). First, the array-based CGH technique applied is outlined in detail. Next, its application in the analysis of C-ALCL tumor specimens is described. This approach resulted in the identification of highly recurrent chromosomal alterations in C-ALCL that include gain of 7q31 and loss on 6q16-6q21 and 13q34, each affecting 45% of the patients. The pattern characteristic of C-ALCL differs markedly from chromosomal alterations observed in other CTCL such as mycosis fungoides and Sézary syndrome and yielded several candidate genes with potential relevance in the pathogenesis of C-ALCL.

  11. Digital Control Analysis and Design of a Field-Sensed Magnetic Suspension System

    PubMed Central

    Li, Jen-Hsing; Chiou, Juing-Shian

    2015-01-01

    Magnetic suspension systems are mechatronic systems and crucial in several engineering applications, such as the levitation of high-speed trains, frictionless bearings, and wind tunnels. Magnetic suspension systems are nonlinear and unstable systems; therefore, they are suitable educational benchmarks for testing various modeling and control methods. This paper presents the digital modeling and control of magnetic suspension systems. First, the magnetic suspension system is stabilized using a digital proportional-derivative controller. Subsequently, the digital model is identified using recursive algorithms. Finally, a digital mixed linear quadratic regulator (LQR)/H∞ control is adopted to stabilize the magnetic suspension system robustly. Simulation examples and a real-world example are provided to demonstrate the practicality of the study results. In this study, a digital magnetic suspension system model was developed and reviewed. In addition, equivalent state and output feedback controls for magnetic suspension systems were developed. Using this method, the controller design for magnetic suspension systems was simplified, which is the novel contribution of this study. In addition, this paper proposes a complete digital controller design procedure for magnetic suspension systems. PMID:25781508

  12. Digital control analysis and design of a field-sensed magnetic suspension system.

    PubMed

    Li, Jen-Hsing; Chiou, Juing-Shian

    2015-03-13

    Magnetic suspension systems are mechatronic systems and crucial in several engineering applications, such as the levitation of high-speed trains, frictionless bearings, and wind tunnels. Magnetic suspension systems are nonlinear and unstable systems; therefore, they are suitable educational benchmarks for testing various modeling and control methods. This paper presents the digital modeling and control of magnetic suspension systems. First, the magnetic suspension system is stabilized using a digital proportional-derivative controller. Subsequently, the digital model is identified using recursive algorithms. Finally, a digital mixed linear quadratic regulator (LQR)/H∞ control is adopted to stabilize the magnetic suspension system robustly. Simulation examples and a real-world example are provided to demonstrate the practicality of the study results. In this study, a digital magnetic suspension system model was developed and reviewed. In addition, equivalent state and output feedback controls for magnetic suspension systems were developed. Using this method, the controller design for magnetic suspension systems was simplified, which is the novel contribution of this study. In addition, this paper proposes a complete digital controller design procedure for magnetic suspension systems.

  13. Analysis of Semi-Active and Passive Suspensions System for Off-Road Vehicles

    NASA Astrophysics Data System (ADS)

    BenLahcene, Zohir; Faris, Waleed F.; Khan, M. D. Raisuddin

    2009-03-01

    The speed of off-road vehicles over rough terrain is generally determined by the ride quality not by the engine power. For this reason, researches are currently being undertaking to improve the ride dynamics of these vehicles using an advanced suspension system. This study intends to provide a preliminary evaluation of whether semi-active suspensions are beneficial to improving ride and handling in off-road vehicles. One of the greatest challenges in designing off-road vehicle suspension system is maintaining a good balance between vehicle ride and handling. Three configurations of these vehicles; 2-axle, 3-xle and 4-axles have been studied and their performances are compared. The application of several control policies of semi-active suspension system, namely skyhook; ground-hook and hybrid controls have been analyzed and compared with passive systems. The results show that the hybrid control policy yields better comfort than a passive suspension, without reducing the road-holding quality or increasing the suspension displacement. The hybrid control policy is also shown to be a better compromise between comfort, road-holding and suspension displacement than the skyhook and ground-hook control policies. Results show an improvement in ride comfort and vehicle handling using 4-axle over 3-axle and 2-axle when emphasis is placed on the response of the vehicle body acceleration, suspension and tyre deflection.

  14. DNA array analysis in a Microsoft Windows environment.

    PubMed

    Conway, T; Kraus, B; Tucker, D L; Smalley, D J; Dorman, A F; McKibben, L

    2002-01-01

    Microsoft Windows-based computers have evolved to the point that they provide sufficient computational and visualization power for robust analysis of DNA array data. In fact, smaller laboratories might prefer to carry out some or all of their analyses and visualization in a Windows environment, rather than alternative platforms such as UNIX. We have developed a series of manually executed macros written in Visual Basic for Microsoft Excel spreadsheets, that allows for rapid and comprehensive gene expression data analysis. The first macro assigns gene names to spots on the DNA array and normalizes individual hybridizations by expressing the signal intensity for each gene as a percentage of the sum of all gene intensities. The second macro streamlines statistical consideration of the confidence in individual gene measurements for sets of experimental replicates by calculating probability values with the Student's t test. The third macro introduces a threshold value, calculates expression ratios between experimental conditions, and calculates the standard deviation of the mean of the log ratio values. Selected columns of data are copied by a fourth macro to create a processed data set suitable for entry into a Microsoft Access database. An Access database structure is described that allows simple queries across multiple experiments and export of data into third-party data visualization software packages. These analysis tools can be used in their present form by others working with commercial E. coli membrane arrays, or they may be adapted for use with other systems. The Excel spreadsheets with embedded Visual Basic macros and detailed instructions for their use are available at http://www.ou.edu/microarray.

  15. Suspension Geometry Measuring

    NASA Astrophysics Data System (ADS)

    Kao, M. J.; Yu, C. C.; Chang, H.; Tsung, T. T.; Lin, H. M.

    2006-10-01

    This paper describes the instrumentation and analysis of the Vehicle suspension's electrical signals. It will measure the Vehicle suspensions' Vertical Displacement, Track Change, Camber Angle, Caster Angle Steer Angle and convert physical quantity into electrical signals in a various vehicle load change. With using electrical signals for computer control, the electrical controlled vehicle has brought great convenience, great safety and thoughtful kindness vehicle system in our daily life. It will measure the Vehicle suspensions' Vertical Displacement, Track Change, Camber Angle, Caster Angle Steer Angle and convert physical quantity into electrical signals in a various vehicle load change. The function of a suspension system in an automobile is to improve ride comfort and stability. Advances in electronic control technology, applied to the automobile, can improve those functions. The results show that the photocell can convert the electrical signals of suspension for peripheral communications link between the vehicle driving and the electronic control unit (ECU) employed for processing.

  16. Spectral Cytometry Has Unique Properties Allowing Multicolor Analysis of Cell Suspensions Isolated from Solid Tissues

    PubMed Central

    Schmutz, Sandrine; Valente, Mariana

    2016-01-01

    Flow cytometry, initially developed to analyze surface protein expression in hematopoietic cells, has increased in analytical complexity and is now widely used to identify cells from different tissues and organisms. As a consequence, data analysis became increasingly difficult due the need of large multi-parametric compensation matrices and to the eventual auto-fluorescence frequently found in cell suspensions obtained from solid organs. In contrast with conventional flow cytometry that detects the emission peak of fluorochromes, spectral flow cytometry distinguishes the shapes of emission spectra along a large range of continuous wave lengths. The data is analyzed with an algorithm that replaces compensation matrices and treats auto-fluorescence as an independent parameter. Thus, spectral flow cytometry should be capable to discriminate fluorochromes with similar emission peaks and provide multi-parametric analysis without compensation requirements. Here we show that spectral flow cytometry achieves a 21-parametric (19 fluorescent probes) characterization and deals with auto-fluorescent cells, providing high resolution of specifically fluorescence-labeled populations. Our results showed that spectral flow cytometry has advantages in the analysis of cell populations of tissues difficult to characterize in conventional flow cytometry, such as heart and intestine. Spectral flow cytometry thus combines the multi-parametric analytical capacity of the highest performing conventional flow cytometry without the requirement for compensation and enabling auto-fluorescence management. PMID:27500930

  17. Thermal Sensor Arrays for The Combinatorial Analysis of Thin Films

    NASA Astrophysics Data System (ADS)

    McCluskey, Patrick James

    2011-12-01

    Membrane-based thermal sensor arrays were developed for the high-throughput analysis of the thermophysical properties of thin films. The continuous growth of integrated circuits and microelectromechanical systems, as well as the development of functional materials and the optimization of materials properties, have produced the need for instruments capable of fast materials screening and analysis at reduced length scales. Two instruments were developed based on a similar architecture, one to measure thermal transport properties and the other to perform calorimetry measurements. Both have the capability to accelerate the pace of materials development and understanding using combinatorial measurement methods. The shared architecture of the instruments consists of a silicon-based micromachined array of thermal sensors. Each sensor consists of a SiN X membrane and a W heating element that also serves as a temperature gauge. The array design allows the simultaneous creation of a library of thin film samples by various deposition techniques while systematically varying a parameter of interest across the device. The membrane-based sensors have little thermal mass making them extremely sensitive to changes in thermal energy. The nano-thermal transport array has an array of sensors optimized for sensitivity to heat loss. The heat loss is determined from the temperature response of the sensor to an applied current. An analytical model is used with a linear regression analysis to fit the thermal properties of the samples to the temperature response. The assumptions of the analytical model are validated with a finite element model. Measured thermal properties include specific heat, thermal effusivity, thermal conductivity, and emissivity. The technique is demonstrated by measuring the thermal transport properties of sputter deposited Cu multilayers with a total film thickness from 15 to 470 nm. The experimental results compare well to a theory based on electronic thermal

  18. Head movement: a novel serotonin-sensitive behavioral endpoint for tail suspension test analysis.

    PubMed

    Lockridge, Amber; Newland, Brett; Printen, Spencer; Romero, Gabriel E; Yuan, Li-Lian

    2013-06-01

    The tail suspension test (TST) as an antidepressant and depression-related behavior screen, has many advantages over the forced swim test (FST) in terms of procedural simplicity and consistent SSRI response. However, the FST has traditionally offered more specific neuromodulatory information by differentiating between serotonin (5-HT) and norepinephrine sensitive behavior categories. Head movement is a newly characterized behavior endpoint in the FST and TST with a selective 5-HT sensitivity. In this investigation, we show that the baseline and drug response profile of head movement previously found in the 129S6 strain of mice (Lockridge et al., 2010) is reproducible in the C57 strain. Head movement is inversely correlated to FST swimming and elevated in the TST by SSRI administration. The use of a weighted bin sample analysis method differentiates TST behaviors into fluoxetine-responsive head movement and desipramine-responsive struggling. The use of 5-HT subtype receptor agonists, after depleting endogenous 5-HT with pCPA, shows the head movement suppressing effect of 5-HT2A and 5-HT2C postsynaptic receptor activation. 5-HT1A and 5-HT1B agonists were ineffective. We propose that a head movement focused analysis can add sensitive and reliable 5-HT detection capability to mouse TST testing with minimal effort but significant reward.

  19. Applications of DNA tiling arrays for whole-genome analysis.

    PubMed

    Mockler, Todd C; Chan, Simon; Sundaresan, Ambika; Chen, Huaming; Jacobsen, Steven E; Ecker, Joseph R

    2005-01-01

    DNA microarrays are a well-established technology for measuring gene expression levels. Microarrays designed for this purpose use relatively few probes for each gene and are biased toward known and predicted gene structures. Recently, high-density oligonucleotide-based whole-genome microarrays have emerged as a preferred platform for genomic analysis beyond simple gene expression profiling. Potential uses for such whole-genome arrays include empirical annotation of the transcriptome, chromatin-immunoprecipitation-chip studies, analysis of alternative splicing, characterization of the methylome (the methylation state of the genome), polymorphism discovery and genotyping, comparative genome hybridization, and genome resequencing. Here we review different whole-genome microarray designs and applications of this technology to obtain a wide variety of genomic scale information.

  20. Experimental Study of Membrane Fouling during Crossflow Microfiltration of Yeast and Bacteria Suspensions: Towards an Analysis at the Microscopic Level.

    PubMed

    Hassan, Ines Ben; Ennouri, Monia; Lafforgue, Christine; Schmitz, Philippe; Ayadi, Abdelmoneim

    2013-05-10

    Microfiltration of model cell suspensions combining macroscopic and microscopic approaches was studied in order to better understand microbial membrane fouling mechanisms. The respective impact of Saccharomyces cerevisiae yeast and Escherichia coli bacteria on crossflow microfiltration performances was investigated using a multichannel ceramic 0.2 µm membrane. Pure yeast suspensions (5 µm ovoid cells) and mixtures of yeast and bacteria (1 to 2.5 µm rod shape cells) were considered in order to analyse the effect of interaction between these two microorganisms on fouling reversibility. The resistances varied significantly with the concentration and characteristics of the microorganisms. Membrane fouling with pure yeast suspension was mainly reversible. For yeast and bacteria mixed suspensions (6 g L-1 yeast concentration) the increase in bacteria from 0.15 to 0.30 g L-1 increased the percentage of normalized reversible resistance. At 10 g L-1 yeast concentration, the addition of bacteria tends to increase the percentage of normalized irreversible resistance. For the objective of performing local analysis of fouling, an original filtration chamber allowing direct in situ observation of the cake by confocal laser scanning microscopy (CLSM) was designed, developed and validated. This device will be used in future studies to characterize cake structure at the microscopic scale.

  1. Analysis of Anionic Polymer Dispersant Behavior in Dense Silicon Nitride and Carbide Suspensions Using an AFM

    NASA Astrophysics Data System (ADS)

    Nojiri, M.; Matsui, S.; Hasegawa, H.; Ono, T.; Fukuda, Y.; Tsukada, M.; Kamiya, H.

    2001-06-01

    The paper focuses on the interaction mechanism caused by anionic polymer dispersants in dense silicon nitride and silicon carbide suspensions. An atomic force microscope (AFM) was used to determine the relationship between the macroscopic suspension viscosity and the microscopic structure adsorbing of a polymer dispersant at the solid/liquid interface. The surface interactions within the suspensions were analyzed under various dispersant pH values and additive conditions. The addition of an anionic polymer dispersant decreased the viscosity of silicon nitride and silicon carbide suspension and increased the electrosteric repulsive force on the non-oxide surface in solution at pH > 6, which was the isoelectric point of the materials. Based on the above results, we estimated the adsorption mechanism of anionic polymer dispersants on each solid surface in solution under relatively high pH conditions.

  2. Airborne electronically steerable phased array. [steerable antennas - systems analysis

    NASA Technical Reports Server (NTRS)

    Coats, R.

    1975-01-01

    Results of a study directed to the design of a lightweight high-gain, spaceborne communications array are presented. The array includes simultaneous transmission and receiving, automatic acquisition and tracking of a signal within a 60-degree cone from the array normal, and provides for independent forming of the transmit and receive beams. Application for this array is the space shuttle, space station, or any of the advanced manned (or unmanned) orbital vehicles. Performance specifications are also given.

  3. Phased Array Antenna Analysis Using Hybrid Finite Element Methods

    DTIC Science & Technology

    1993-06-01

    Waveguide ; (b) Geometry Model for Method of Moments ........................ 4 2. Printed Dipole Radiator: (a) Actual Geometry with Microstrip Balun and...Finite Elem ents . ............................................. 19 11. Equivalence Model for Waveguide /Cavity Problem: (a) Original Problem; (b... Waveguide Array Active Reflection Coefficient - Comparison of Results Uscig Cavity Array (CAVIARR) and General Array (PARANA) Models . 76 45. Rectangular

  4. Time response analysis in suspension system design of a high-speed car

    NASA Astrophysics Data System (ADS)

    Pagwiwoko, Cosmas Pandit

    2010-03-01

    A land speed record vehicle is designed to run on a flat surface like salt lake where the wheels are normally made from solid metal with a special suspension system. The suspension is designed to provide a stable platform to keep the wheel treads on tract, to insulate the car and the driver from the surface irregularities and to take part of good handling properties. The surface condition of the lake beds is basically flat without undulations but with inconsistent surface textures and ridges. Spring with nonlinear rate is used with the reason that the resistance builds up roughly proportional to the aerodynamic download for keeping the height more nearly constant. The objective of the work is to produce an efficient method for assisting the design of suspension system. At the initial step, the stiffness and the damping constants are determined based on RMS optimization by following the optimization strategy i.e. to minimize the absolute acceleration respect to the relative displacement of the suspension. Power bond graph technique is then used to model the nonlinearity of the components i.e. spring and dashpot of the suspension system. This technique also enables to incorporate the interactions of dynamic response of the vehicle's body with aerodynamic flow as a result of the base excitation of the ground to the wheels. The simulation is conducted on the platform of Simulink-MATLAB and the interactions amongst the components within the system are observed in time domain to evaluate the effectiveness of the suspension.

  5. Time response analysis in suspension system design of a high-speed car

    NASA Astrophysics Data System (ADS)

    Pagwiwoko, Cosmas Pandit

    2009-12-01

    A land speed record vehicle is designed to run on a flat surface like salt lake where the wheels are normally made from solid metal with a special suspension system. The suspension is designed to provide a stable platform to keep the wheel treads on tract, to insulate the car and the driver from the surface irregularities and to take part of good handling properties. The surface condition of the lake beds is basically flat without undulations but with inconsistent surface textures and ridges. Spring with nonlinear rate is used with the reason that the resistance builds up roughly proportional to the aerodynamic download for keeping the height more nearly constant. The objective of the work is to produce an efficient method for assisting the design of suspension system. At the initial step, the stiffness and the damping constants are determined based on RMS optimization by following the optimization strategy i.e. to minimize the absolute acceleration respect to the relative displacement of the suspension. Power bond graph technique is then used to model the nonlinearity of the components i.e. spring and dashpot of the suspension system. This technique also enables to incorporate the interactions of dynamic response of the vehicle's body with aerodynamic flow as a result of the base excitation of the ground to the wheels. The simulation is conducted on the platform of Simulink-MATLAB and the interactions amongst the components within the system are observed in time domain to evaluate the effectiveness of the suspension.

  6. Performance analysis of a semiactive suspension system with particle swarm optimization and fuzzy logic control.

    PubMed

    Qazi, Abroon Jamal; de Silva, Clarence W; Khan, Afzal; Khan, Muhammad Tahir

    2014-01-01

    This paper uses a quarter model of an automobile having passive and semiactive suspension systems to develop a scheme for an optimal suspension controller. Semi-active suspension is preferred over passive and active suspensions with regard to optimum performance within the constraints of weight and operational cost. A fuzzy logic controller is incorporated into the semi-active suspension system. It is able to handle nonlinearities through the use of heuristic rules. Particle swarm optimization (PSO) is applied to determine the optimal gain parameters for the fuzzy logic controller, while maintaining within the normalized ranges of the controller inputs and output. The performance of resulting optimized system is compared with different systems that use various control algorithms, including a conventional passive system, choice options of feedback signals, and damping coefficient limits. Also, the optimized semi-active suspension system is evaluated for its performance in relation to variation in payload. Furthermore, the systems are compared with respect to the attributes of road handling and ride comfort. In all the simulation studies it is found that the optimized fuzzy logic controller surpasses the other types of control.

  7. Performance Analysis of a Semiactive Suspension System with Particle Swarm Optimization and Fuzzy Logic Control

    PubMed Central

    Qazi, Abroon Jamal; de Silva, Clarence W.

    2014-01-01

    This paper uses a quarter model of an automobile having passive and semiactive suspension systems to develop a scheme for an optimal suspension controller. Semi-active suspension is preferred over passive and active suspensions with regard to optimum performance within the constraints of weight and operational cost. A fuzzy logic controller is incorporated into the semi-active suspension system. It is able to handle nonlinearities through the use of heuristic rules. Particle swarm optimization (PSO) is applied to determine the optimal gain parameters for the fuzzy logic controller, while maintaining within the normalized ranges of the controller inputs and output. The performance of resulting optimized system is compared with different systems that use various control algorithms, including a conventional passive system, choice options of feedback signals, and damping coefficient limits. Also, the optimized semi-active suspension system is evaluated for its performance in relation to variation in payload. Furthermore, the systems are compared with respect to the attributes of road handling and ride comfort. In all the simulation studies it is found that the optimized fuzzy logic controller surpasses the other types of control. PMID:24574868

  8. Rate equations analysis of phase-locked semiconductor laser arrays under steady state conditions

    NASA Technical Reports Server (NTRS)

    Katz, J.; Kapon, E.; Margalit, S.; Yariv, A.

    1984-01-01

    Rate equations analysis of phase-locked semiconductor laser arrays has been carried out. It was found that for given (laser) current densities, the photon density distribution in the array elements is that particular one which maximizes the total photon density. The results of this analysis were then combined with the waveguide properties of the laser array waveguide, yielding a basic model of phase-locked diode laser arrays. This model explains the effects of the variation of the current combination through the array elements on its mode structure that were observed recently.

  9. Joint Analysis of BICEP2/Keck Array and Planck Data

    NASA Astrophysics Data System (ADS)

    BICEP2/Keck and Planck Collaborations; Ade, P. A. R.; Aghanim, N.; Ahmed, Z.; Aikin, R. W.; Alexander, K. D.; Arnaud, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barkats, D.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Benton, S. J.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bischoff, C. A.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Brevik, J. A.; Bucher, M.; Buder, I.; Bullock, E.; Burigana, C.; Butler, R. C.; Buza, V.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chary, R.-R.; Chiang, H. C.; Christensen, P. R.; Colombo, L. P. L.; Combet, C.; Connors, J.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; De Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dowell, C. D.; Duband, L.; Ducout, A.; Dunkley, J.; Dupac, X.; Dvorkin, C.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Filippini, J. P.; Finelli, F.; Fliescher, S.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Gjerløw, E.; Golwala, S. R.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Halpern, M.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Hasselfield, M.; Helou, G.; Henrot-Versillé, S.; Herranz, D.; Hildebrandt, S. R.; Hilton, G. C.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hovest, W.; Hristov, V. V.; Huffenberger, K. M.; Hui, H.; Hurier, G.; Irwin, K. D.; Jaffe, A. H.; Jaffe, T. R.; Jewell, J.; Jones, W. C.; Juvela, M.; Karakci, A.; Karkare, K. S.; Kaufman, J. P.; Keating, B. G.; Kefeli, S.; Keihänen, E.; Kernasovskiy, S. A.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kovac, J. M.; Krachmalnicoff, N.; Kunz, M.; Kuo, C. L.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leitch, E. M.; Leonardi, R.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Lueker, M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Mason, P.; Matarrese, S.; Megerian, K. G.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nguyen, H. T.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; O'Brient, R.; Ogburn, R. W.; Orlando, A.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Pettorino, V.; Piacentini, F.; Piat, M.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Pratt, G. W.; Prunet, S.; Pryke, C.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Richter, S.; Ristorcelli, I.; Rocha, G.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Schwarz, R.; Scott, D.; Seiffert, M. D.; Sheehy, C. D.; Spencer, L. D.; Staniszewski, Z. K.; Stolyarov, V.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Teply, G. P.; Terenzi, L.; Thompson, K. L.; Toffolatti, L.; Tolan, J. E.; Tomasi, M.; Tristram, M.; Tucci, M.; Turner, A. D.; Valenziano, L.; Valiviita, J.; van Tent, B.; Vibert, L.; Vielva, P.; Vieregg, A. G.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Watson, R.; Weber, A. C.; Wehus, I. K.; White, M.; White, S. D. M.; Willmert, J.; Wong, C. L.; Yoon, K. W.; Yvon, D.; Zacchei, A.; Zonca, A.; Bicep2/Keck; Planck Collaborations

    2015-03-01

    We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg2 patch of sky centered on RA 0 h, Dec. -57.5 ° . The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 μ K deg in Q and U at 143 GHz). We detect 150 ×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-Λ CDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r0.05<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0 σ significance.

  10. Joint analysis of BICEP2/keck array and Planck Data.

    PubMed

    Ade, P A R; Aghanim, N; Ahmed, Z; Aikin, R W; Alexander, K D; Arnaud, M; Aumont, J; Baccigalupi, C; Banday, A J; Barkats, D; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Benton, S J; Bernard, J-P; Bersanelli, M; Bielewicz, P; Bischoff, C A; Bock, J J; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Brevik, J A; Bucher, M; Buder, I; Bullock, E; Burigana, C; Butler, R C; Buza, V; Calabrese, E; Cardoso, J-F; Catalano, A; Challinor, A; Chary, R-R; Chiang, H C; Christensen, P R; Colombo, L P L; Combet, C; Connors, J; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Delouis, J-M; Désert, F-X; Dickinson, C; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dowell, C D; Duband, L; Ducout, A; Dunkley, J; Dupac, X; Dvorkin, C; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Falgarone, E; Filippini, J P; Finelli, F; Fliescher, S; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Ghosh, T; Giard, M; Gjerløw, E; Golwala, S R; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Halpern, M; Hansen, F K; Hanson, D; Harrison, D L; Hasselfield, M; Helou, G; Henrot-Versillé, S; Herranz, D; Hildebrandt, S R; Hilton, G C; Hivon, E; Hobson, M; Holmes, W A; Hovest, W; Hristov, V V; Huffenberger, K M; Hui, H; Hurier, G; Irwin, K D; Jaffe, A H; Jaffe, T R; Jewell, J; Jones, W C; Juvela, M; Karakci, A; Karkare, K S; Kaufman, J P; Keating, B G; Kefeli, S; Keihänen, E; Kernasovskiy, S A; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Knox, L; Kovac, J M; Krachmalnicoff, N; Kunz, M; Kuo, C L; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J-M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leitch, E M; Leonardi, R; Levrier, F; Lewis, A; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Lueker, M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Mangilli, A; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Mason, P; Matarrese, S; Megerian, K G; Meinhold, P R; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M-A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Moss, A; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nguyen, H T; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; O'Brient, R; Ogburn, R W; Orlando, A; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Partridge, B; Pasian, F; Patanchon, G; Pearson, T J; Perdereau, O; Perotto, L; Pettorino, V; Piacentini, F; Piat, M; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Pratt, G W; Prunet, S; Pryke, C; Puget, J-L; Rachen, J P; Reach, W T; Rebolo, R; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Richter, S; Ristorcelli, I; Rocha, G; Rossetti, M; Roudier, G; Rowan-Robinson, M; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Schwarz, R; Scott, D; Seiffert, M D; Sheehy, C D; Spencer, L D; Staniszewski, Z K; Stolyarov, V; Sudiwala, R; Sunyaev, R; Sutton, D; Suur-Uski, A-S; Sygnet, J-F; Tauber, J A; Teply, G P; Terenzi, L; Thompson, K L; Toffolatti, L; Tolan, J E; Tomasi, M; Tristram, M; Tucci, M; Turner, A D; Valenziano, L; Valiviita, J; Van Tent, B; Vibert, L; Vielva, P; Vieregg, A G; Villa, F; Wade, L A; Wandelt, B D; Watson, R; Weber, A C; Wehus, I K; White, M; White, S D M; Willmert, J; Wong, C L; Yoon, K W; Yvon, D; Zacchei, A; Zonca, A

    2015-03-13

    We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400  deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2  μK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150  GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

  11. Copy Number Variation Analysis by Array Analysis of Single Cells Following Whole Genome Amplification.

    PubMed

    Dimitriadou, Eftychia; Zamani Esteki, Masoud; Vermeesch, Joris Robert

    2015-01-01

    Whole genome amplification is required to ensure the availability of sufficient material for copy number variation analysis of a genome deriving from an individual cell. Here, we describe the protocols we use for copy number variation analysis of non-fixed single cells by array-based approaches following single-cell isolation and whole genome amplification. We are focusing on two alternative protocols, an isothermal and a PCR-based whole genome amplification method, followed by either comparative genome hybridization (aCGH) or SNP array analysis, respectively.

  12. A control performance analysis for MacPherson active suspension system under bounce sine sweep road profile

    NASA Astrophysics Data System (ADS)

    Ismail, M. Fahezal; Sam, Yahaya Md.; Sudin, Shahdan; Aripin, M. Khairi

    2016-10-01

    This paper studies a control performance analysis for MacPherson active suspension system. The ride comfort quality is a very important specification for modern automotive suspension system. The Proportional Integral Sliding Mode Control-Evolutionary Strategy-Composite Nonlinear Feedback (PISMC-ES-CNF) controller is designed to solve the transient problem occurred in vertical acceleration of sprung mass. The control performance is tested by using PISMC-ES-CNF and compared with Sliding Mode Controller (SMC) and Composite Nonlinear Feedback (CNF) under Bounce Sine Sweep road profile. The ISO 2631-1, 1997 is a standard for vertical acceleration of sprung mass level and degree of comfort. The one way Analysis of Variance (ANOVA) and standard deviation have showed that the PISMC- ES-CNF controller compared with others controllers achieved the best control performance.

  13. ArrayExplorer, a program in Visual Basic for robust and accurate filter cDNA array analysis.

    PubMed

    Patriotis, P C; Querec, T D; Gruver, B N; Brown, T R; Patriotis, C

    2001-10-01

    Determining the dynamics in the global regulation of gene expression holds the promise of bringing a better understanding of the processes that govern physiological cell growth regulation and its disruption during the development of disease. The advent for cDNA arrays has created the possibility for the parallel analysis of expression of thousands of genes in a given cell population, simultaneously. The level of expression of a given set of genes within the studied tissue corresponds to the intensity of a labeled cDNA probe synthesized from the studied tissue RNA and bound specifically to the cDNAs of the genes spotted on the array. The accurate extraction of gene expression intensity values is essential for further data analysis and the interpretation of the obtained results. Here, we describe a new array image-processing software developed in Microsoft Visual Basic, the ArrayExplorer, which provides a user-friendly, multiple-window interface and a number of automatic and manual features that facilitate a reliable, robust, and accurate extraction of gene intensity values from filter-array images.

  14. The Murchison Widefield Array 21 cm Power Spectrum Analysis Methodology

    NASA Astrophysics Data System (ADS)

    Jacobs, Daniel C.; Hazelton, B. J.; Trott, C. M.; Dillon, Joshua S.; Pindor, B.; Sullivan, I. S.; Pober, J. C.; Barry, N.; Beardsley, A. P.; Bernardi, G.; Bowman, Judd D.; Briggs, F.; Cappallo, R. J.; Carroll, P.; Corey, B. E.; de Oliveira-Costa, A.; Emrich, D.; Ewall-Wice, A.; Feng, L.; Gaensler, B. M.; Goeke, R.; Greenhill, L. J.; Hewitt, J. N.; Hurley-Walker, N.; Johnston-Hollitt, M.; Kaplan, D. L.; Kasper, J. C.; Kim, HS; Kratzenberg, E.; Lenc, E.; Line, J.; Loeb, A.; Lonsdale, C. J.; Lynch, M. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Neben, A. R.; Thyagarajan, N.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Paul, S.; Prabu, T.; Procopio, P.; Riding, J.; Rogers, A. E. E.; Roshi, A.; Udaya Shankar, N.; Sethi, Shiv K.; Srivani, K. S.; Subrahmanyan, R.; Tegmark, M.; Tingay, S. J.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L.; Wu, C.; Wyithe, J. S. B.

    2016-07-01

    We present the 21 cm power spectrum analysis approach of the Murchison Widefield Array Epoch of Reionization project. In this paper, we compare the outputs of multiple pipelines for the purpose of validating statistical limits cosmological hydrogen at redshifts between 6 and 12. Multiple independent data calibration and reduction pipelines are used to make power spectrum limits on a fiducial night of data. Comparing the outputs of imaging and power spectrum stages highlights differences in calibration, foreground subtraction, and power spectrum calculation. The power spectra found using these different methods span a space defined by the various tradeoffs between speed, accuracy, and systematic control. Lessons learned from comparing the pipelines range from the algorithmic to the prosaically mundane; all demonstrate the many pitfalls of neglecting reproducibility. We briefly discuss the way these different methods attempt to handle the question of evaluating a significant detection in the presence of foregrounds.

  15. Analysis of the causes of recurrence after frontalis suspension using silicone rods for congenital ptosis

    PubMed Central

    Kim, Chang Yeom; Son, Byeong Jae; Son, Jangyup; Hong, Jongill; Lee, Sang Yeul

    2017-01-01

    Background Silicone rod is a commonly used synthetic suspension material in frontalis suspension surgery to correct blepharoptosis. The most challenging problem and a decisive drawback of the use of silicone rod is a considerable rate of ptosis recurrence after surgery. We examined patients with recurred ptosis and assessed the physical and micromorphological properties of implanted silicone rods to determine the causative mechanisms of recurred ptosis after frontalis suspension using silicone rod. Methods This is a prospective observational case series of 22 pediatric patients with recurred ptosis after frontalis suspension using silicone rods for congenital ptosis. Implanted silicone rods were observed and removed during the operation for correction of recurred ptosis. The removed silicone rods were physically and micromorphologically evaluated to determine the cause of recurrence. Results Pretarsal fixation positions migrated upward, whereas suprabrow fixation positions migrated downward during ptosis recurrence. The breaking strength of implanted silicone rods was reduced by approximately 50% during 3 years. Cracks, debris, and loss of homogenous structure with disintegration were observed on scanning electron micrographs of implanted silicone rods in patients with recurred ptosis. Preoperative severe degree of ptosis also contributed to recurred ptosis. Conclusions Recurrence of ptosis after frontalis suspension using silicone rod was associated with physical changes of implanted silicone rods, including positional migration, weakened tensile strength, and micromorphological changes in combination with patients’ characteristics. PMID:28207846

  16. Assessment of formulation robustness for nano-crystalline suspensions using failure mode analysis or derisking approach.

    PubMed

    Nakach, Mostafa; Authelin, Jean-René; Voignier, Cecile; Tadros, Tharwat; Galet, Laurence; Chamayou, Alain

    2016-06-15

    The small particle size of nano-crystalline suspensions can be responsible for their physical instability during drug product preparation (downstream processing), storage and administration. For that purpose, the commercial formulation needs to be sufficiently robust to various triggering conditions, such as ionic strength, shear rate, wetting/dispersing agent desorption by dilution, temperature and pH variation. In our previous work we described a systematic approach to select the suitable wetting/dispersant agent for the stabilization of nano-crystalline suspension. In this paper, we described the assessment of the formulation robustness (stabilized using a mixture of sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone (PVP) and) by measuring the rate of perikinetic (diffusion-controlled) and orthokinetic (shear-induced) aggregation as a function of ionic strength, temperature, pH and dilution. The results showed that, using the SDS/PVP system, the critical coagulation concentration is about five times higher than that observed in the literature for suspension colloidaly stable at high concentration. The nano-suspension was also found to be very stable at ambient temperature and at different pH conditions. Desorption test confirmed the high affinity between API and wetting/dispersing agent. However, the suspension undergoes aggregation at high temperature due to the desorption of the wetting/dispersing agent and disaggregation of SDS micelles. Furthermore, aggregation occurs at very high shear rate (orhokinetic aggregation) by overcoming the energy barrier responsible for colloidal stability of the system.

  17. MATRIX DISCRIMINANT ANALYSIS WITH APPLICATION TO COLORIMETRIC SENSOR ARRAY DATA.

    PubMed

    Zhong, Wenxuan; Suslick, Kenneth S

    2015-09-01

    With the rapid development of nano-technology, a "colorimetric sensor array" (CSA) which is referred to as an optical electronic nose has been developed for the identification of toxicants. Unlike traditional sensors which rely on a single chemical interaction, CSA can measure multiple chemical interactions by using chemo-responsive dyes. The color changes of the chemo-responsive dyes are recorded before and after exposure to toxicants and serve as a template for classification. The color changes are digitalized in the form of a matrix with rows representing dye effects and columns representing the spectrum of colors. Thus, matrix-classification methods are highly desirable. In this article, we develop a novel classification method, matrix discriminant analysis (MDA), which is a generalization of linear discriminant analysis (LDA) for the data in matrix form. By incorporating the intrinsic matrix-structure of the data in discriminant analysis, the proposed method can improve CSA's sensitivity and more importantly, specificity. A penalized MDA method, PMDA, is also introduced to further incorporate sparsity structure in discriminant function. Numerical studies suggest that the proposed MDA and PMDA methods outperform LDA and other competing discriminant methods for matrix predictors. The asymptotic consistency of MDA is also established. R code and data are available online as supplementary material.

  18. Simulation analysis of the EUSAMA Plus suspension testing method including the impact of the vehicle untested side

    NASA Astrophysics Data System (ADS)

    Dobaj, K.

    2016-09-01

    The work deals with the simulation analysis of the half car vehicle model parameters on the suspension testing results. The Matlab simulation software was used. The considered model parameters are involved with the shock absorber damping coefficient, the tire radial stiffness, the car width and the rocker arm length. The consistent vibrations of both test plates were considered. Both wheels of the car were subjected to identical vibration, with frequency changed similar to the EUSAMA Plus principle. The shock absorber damping coefficient (for several values of the car width and rocker arm length) was changed on one and both sides of the vehicle. The obtained results are essential for the new suspension testing algorithm (basing on the EUSAMA Plus principle), which will be the aim of the further author's work.

  19. COMPOSITE CERAMIC ARMOR DEFECT ANALYSIS USING PHASED ARRAY ULTRASOUND

    DTIC Science & Technology

    2011-01-30

    background variation. Such an approximation applied to the FFT results of Conclusion Phased - array ultrasonic inspection methods have been...SNR values above 2.55) were statistically defective either. CONCLUSION Phased - array ultrasonic inspection methods have been successfully applied to...4 G.P. Singh and J. W. Davies, “Multiple Transducer Ultrasonic Techniques: Phased Arrays ” In Nondestructive Testing Handbook, 2nd Ed., 7, pp. 284

  20. Evolutionary insights from suffix array-based genome sequence analysis.

    PubMed

    Poddar, Anindya; Chandra, Nagasuma; Ganapathiraju, Madhavi; Sekar, K; Klein-Seetharaman, Judith; Reddy, Raj; Balakrishnan, N

    2007-08-01

    Gene and protein sequence analyses, central components of studies in modern biology are easily amenable to string matching and pattern recognition algorithms. The growing need of analysing whole genome sequences more efficiently and thoroughly, has led to the emergence of new computational methods. Suffix trees and suffix arrays are data structures, well known in many other areas and are highly suited for sequence analysis too. Here we report an improvement to the design of construction of suffix arrays. Enhancement in versatility and scalability, enabled by this approach, is demonstrated through the use of real-life examples. The scalability of the algorithm to whole genomes renders it suitable to address many biologically interesting problems. One example is the evolutionary insight gained by analysing unigrams, bi-grams and higher n-grams, indicating that the genetic code has a direct influence on the overall composition of the genome. Further, different proteomes have been analysed for the coverage of the possible peptide space, which indicate that as much as a quarter of the total space at the tetra-peptide level is left un-sampled in prokaryotic organisms, although almost all tri-peptides can be seen in one protein or another in a proteome. Besides, distinct patterns begin to emerge for the counts of particular tetra and higher peptides, indicative of a 'meaning' for tetra and higher n-grams. The toolkit has also been used to demonstrate the usefulness of identifying repeats in whole proteomes efficiently. As an example, 16 members of one COG,coded by the genome of Mycobacterium tuberculosis H37Rv have been found to contain a repeating sequence of 300 amino acids.

  1. Seismic Background Noise Analysis of Brtr (PS-43) Array

    NASA Astrophysics Data System (ADS)

    Bakir, M. E.; Meral Ozel, N.; Semin, K. U.

    2014-12-01

    The seismic background noise variation of BRTR array, composed of two sub arrays located in Ankara and in Kırıkkale-Keskin, has been investigated by calculating Power Spectral Density and Probability Density Functions for seasonal and diurnal noise variations between 2005 and 2011. PSDs were computed within the frequency range of 100 s - 10 Hz. The results show us a little change in noise conditions in terms of time and location. Especially, noise level changes were observed at 3-5 Hz in diurnal variations at Keskin array and there is a 5-7 dB difference in day and night time in cultural noise band (1-10 Hz). On the other hand, noise levels of medium period array are high in 1-2 Hz frequency range. High noise levels were observed in daily working times when we compared to night-time in cultural noise band. The seasonal background noise variation at both sites also shows very similar properties to each other. Since both arrays consist ofborehole instruments and away from the coasts, we saw a small change in noise levels caused by microseism. Comparison between Keskin short period array and Ankara medium period array show us Keskin array is quiter than Ankara array.

  2. Seismic Background Noise Analysis of BRTR (PS-43) Array

    NASA Astrophysics Data System (ADS)

    Ezgi Bakir, Mahmure; Meral Ozel, Nurcan; Umut Semin, Korhan

    2015-04-01

    The seismic background noise variation of BRTR array, composed of two sub arrays located in Ankara and in Ankara-Keskin, has been investigated by calculating Power Spectral Density and Probability Density Functions for seasonal and diurnal noise variations between 2005 and 2011. PSDs were computed within the frequency range of 100 s - 10 Hz. The results show us a little change in noise conditions in terms of time and location. Especially, noise level changes were observed at 3-5 Hz in diurnal variations at Keskin array and there is a 5-7 dB difference in day and night time in cultural noise band (1-10 Hz). On the other hand, noise levels of medium period array is high in 1-2 Hz frequency rather than short period array. High noise levels were observed in daily working times when we compare it to night-time in cultural noise band. The seasonal background noise variation at both sites also shows very similar properties to each other. Since these stations are borehole instruments and away from the coasts, we saw a small change in noise levels caused by microseism. Comparison between Keskin short period array and Ankara medium period array show us Keskin array is quiter than Ankara array.

  3. GEO Satellite Solar Array Abnormality's Analysis and Treatment

    NASA Astrophysics Data System (ADS)

    Wang, Junyan; Yang, Yujie; Zhu, Weibo; Liu, Jingyong; Xu, Hui

    Solar array, converting sunlight into electricity, is one of the most important components in satellite energy subsystem. It is significant for in-orbit satellite safety that solar array and its subsidiaries work normally. An abnormal phenomenon that the output current of one solar array suddenly decreased happened in a GEO satellite. Combined with the structure of the solar array system and the trends of relevant parameters during the abnormality, the paper analyzed the possible reasons, and detected the root cause, and finally provided an emergency treatment for this kind of abnormality.

  4. Peptide Arrays for Kinome Analysis of Livestock Species

    PubMed Central

    Daigle, Joanna; Van Wyk, Brenden; Trost, Brett; Scruten, Erin; Arsenault, Ryan; Kusalik, Anthony; Griebel, Philip John; Napper, Scott

    2014-01-01

    Reversible protein phosphorylation is a central mechanism for both the transfer of intracellular information and the initiation of cellular responses. Within human medicine, considerable emphasis is placed on understanding and controlling the enzymes (kinases) that are responsible for catalyzing these modifications. This is evident in the prominent use of kinase inhibitors as drugs as well as the trend to understand complex biology and identify biomarkers via characterizations of global kinase (kinome) activity. Despite the demonstrated value of focusing on kinome activity, the application of this perspective to livestock has been restricted by the absence of appropriate research tools. In this review, we discuss the development of software platforms that facilitate the development and application of species-specific peptide arrays for kinome analysis of livestock. Examples of the application of kinomic approaches to a number of priority species (cattle, pigs, and chickens) in a number of biological contexts (infections, biomarker discovery, and food quality) are presented as are emerging trends for kinome analysis of livestock. PMID:26664912

  5. Analysis of Eigenspace Dynamics with Applications to Array Processing

    DTIC Science & Technology

    2014-09-30

    drifting arrays strongly affected by deformation or array-depth perturbations. The long-term goal of this effort is the development of physically...J., “Measurements of three-dimensional propagation in a continental shelf environment”, J. Acoust. Soc. Am. 125, pp. 1394-1402, 2009

  6. Terrestrial central station array life-cycle analysis support study

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Plant elements evaluated included designs for module, panel and array structures, as well as balance-of-plant systems. Installation and maintenance procedures and the impact of site environment were also evaluated. In terms of the cost of energy produced, the horizontal array configuration was found to be less expensive than the tandem array at latitudes less than 40 deg. Both of these configurations are less expensive than the rack design. However, the costs of energy for all three configurations are within approximately ?10 percent of each other. For flat plate panels, the seasonally adjusted and tracking array configurations are not economically attractive when compared to the three other designs. Balance-of-plant costs are approximately equal to (goal) module costs. The array structures and foundations are the most expensive items in the balance-of-plant costs.

  7. Analysis of finite phased arrays of circular microstrip patches

    NASA Technical Reports Server (NTRS)

    Deshpande, Manohar D.; Bailey, Marion C.

    1989-01-01

    A method is presented for analyzing a finite planar array of circular microstrip patches fed by coaxial probes. The self- and mutual impedances between array elements are calculated using the method of moments with the dyadic Green's function for a dielectric layer on a ground plane. The patch circuits are determined by using the reaction integral equation. The active input impedance as well as the active element pattern of the array are computed from a knowledge of the resultant patch currents. The calculated results for two-element and eight-element linear arrays are in good agreement with experimental data. The active reflection coefficient and element pattern for the center and edge elements of a two-dimensional array as a function of scan angle are also presented.

  8. Analysis of a suspension system for a wheel rolling on a flat track

    NASA Technical Reports Server (NTRS)

    Mcginness, H.

    1978-01-01

    A flexure strut wheel suspension system is described which keeps a wheel flat against the track and maintains a small interface moment. Equations are presented for the evaluation of this moment. A comparison of the flexure strut system is made with a rigid link design containing pivot bearings.

  9. Geometric nonlinear analysis of self-anchored cable-stayed suspension bridges.

    PubMed

    Hui-Li, Wang; Yan-Bin, Tan; Si-Feng, Qin; Zhe, Zhang

    2013-01-01

    Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed.

  10. Geometric Nonlinear Analysis of Self-Anchored Cable-Stayed Suspension Bridges

    PubMed Central

    Hui-Li, Wang; Yan-Bin, Tan; Si-Feng, Qin; Zhe, Zhang

    2013-01-01

    Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed. PMID:24282388

  11. Application of a validated method in the stability study of colistin sulfate and methylparaben in a veterinary suspension formulation by high-performance liquid chromatography with a diode array detector.

    PubMed

    Pérez-Lozano, Pilar; García-Montoya, Encarna; Orriols, Anna; Miñarro, Montse; Ticó, Josep Ramon; Suñé-Negre, Josep Maria

    2007-01-01

    A methodology following International Cooperation on Harmonization for Veterinary Products (VICH) guidelines for the stability evaluation of colistin sulfate in a nonaqueous suspension pharmaceutical dosage form for veterinary use (via their drinking water) is described. This method monitors the percentage of colistin sulfate during the stability study of the preparation in drinking water and establishes the shelf life of the final product by a new high-performance liquid chromatography method which was developed and validated for the simultaneous determination of colistin sulfate [colistin A (Polymixin E1) and colistin B (Polymixin E2)] and methylparaben (Nipagin) using a diode array detector (DAD). The method uses a Kromasil C18 column and isocratic elution. The mobile phase consisted of an acetonitrile-sodium sulfate anhydrous solution (25 + 75) pumped at a flow rate of 1.5 mL/min. The DAD was set at 215 nm. The validation study was carried out according to the VICH guidelines in order to prove that the new analytical method meets the reliability characteristics, which include the fundamental criteria for validation: selectivity, linearity, precision, accuracy, and sensitivity. The method was applied during the quality control or stability studies of the suspension dosage form in order to quantify the drug (colistin) and preservative, and proved to be suitable for rapid and reliable quality control.

  12. Bifurcation analysis of an infinite array of von Karman Streets

    NASA Astrophysics Data System (ADS)

    Ghaemi Oskouei, Babak; Kanso, Eva; Newton, Paul K.

    2008-11-01

    This research investigates the behavior of an infinite array of (inverse) von Karman streets. Primary motivation is to model the wake dynamics in large fish schools. Ignoring the fish we focus on the dynamic interaction of multiple wakes. In particular, we investigate the problem of fluid transport between adjacent vortex streets for its relevance to understanding the transport of oxygen and nutrients to inner fish in large schools as well as understanding flow barriers to passive locomotion. We prove that the configuration of vortices is in relative equilibrium, meaning that the streamline pattern remains steady in the frame moving with vortices. We look at the topology of these streamline patterns plotted in the moving frame which lends insight to fluid transport through the mid-wake region. Fluid is advected along different paths depending on the distance separating two adjacent streets. When the streets are far apart, the dynamics is decoupled and fluid is transported globally between two adjacent streets. When the streets get closer to each other, the number of streets that enter into partnership in transporting fluid among themselves increases. This observation motivates a bifurcation analysis which links the distance between streets to the maximum number of streets transporting fluid among themselves.

  13. Reliability analysis of the solar array based on Fault Tree Analysis

    NASA Astrophysics Data System (ADS)

    Jianing, Wu; Shaoze, Yan

    2011-07-01

    The solar array is an important device used in the spacecraft, which influences the quality of in-orbit operation of the spacecraft and even the launches. This paper analyzes the reliability of the mechanical system and certifies the most vital subsystem of the solar array. The fault tree analysis (FTA) model is established according to the operating process of the mechanical system based on DFH-3 satellite; the logical expression of the top event is obtained by Boolean algebra and the reliability of the solar array is calculated. The conclusion shows that the hinges are the most vital links between the solar arrays. By analyzing the structure importance(SI) of the hinge's FTA model, some fatal causes, including faults of the seal, insufficient torque of the locking spring, temperature in space, and friction force, can be identified. Damage is the initial stage of the fault, so limiting damage is significant to prevent faults. Furthermore, recommendations for improving reliability associated with damage limitation are discussed, which can be used for the redesigning of the solar array and the reliability growth planning.

  14. Preliminary analysis of the Hellenic geomagnetic array stations' response functions

    NASA Astrophysics Data System (ADS)

    di Fiore, B.; Balasis, G.; Kapiris, P.; Daglis, I. A.; Ganas, A.; Melis, N.

    2009-04-01

    The National Observatory of Athens currently operates the HellENIc GeoMagnetic Array (ENIGMA), an array of 4 ground-based magnetometer stations in the area of south-eastern Europe (central and southern Greece). Based on one year (2008) of vector magnetic field data, recorded at the various array sites, magnetic response function estimates are inferred at 5 s - 2048 s. The magnetic response functions are then viewed as real and imaginary induction arrows, detecting sharp conductivity boundaries and providing a picture of the geometry of regional conductors. First results from efforts on inversion and modelling of the ENIGMA magnetic response functions will also be discussed.

  15. Faster Array Training and Rapid Analysis for a Sensor Array Intended for an Event Monitor in Air

    NASA Technical Reports Server (NTRS)

    Homer, Margie L.; Shevade, A. V.; Fonollosa, J.; Huerta, R.

    2013-01-01

    Environmental monitoring, in particular, air monitoring, is a critical need for human space flight. Both monitoring and life support systems have needs for closed loop process feedback and quality control for environmental factors. Monitoring protects the air environment and water supply for the astronaut crew and different sensors help ensure that the habitat falls within acceptable limits, and that the life support system is functioning properly and efficiently. The longer the flight duration and the farther the destination, the more critical it becomes to have carefully monitored and automated control systems for life support. There is an acknowledged need for an event monitor which samples the air continuously and provides near real-time information on changes in the air. Past experiments with the JPL ENose have demonstrated a lifetime of the sensor array, with the software, of around 18 months. We are working on a sensor array and new algorithms that will incorporate transient sensor responses in the analysis. Preliminary work has already showed more rapid quantification and identification of analytes and the potential for faster training time of the array. We will look at some of the factors that contribute to demonstrating faster training time for the array. Faster training will decrease the integrated sensor exposure to training analytes, which will also help extend sensor lifetime.

  16. Phased Array Analysis Using a Modified Chebyshev Approach

    DTIC Science & Technology

    2005-11-01

    define Parray as the average power of the array, Aarray as the effective area of the array, Pelement as the average power of the unweighted element...signal to noise ratio is: (SNR)weighted = Parray Narray = [ N∑ i=1 ãt,iãr,i ]2 [ N∑ i=1 ã2r,i ] (SNR)element (43) where (SNR)element = Pelement

  17. Wave-front analysis using Fresnel lens arrays.

    PubMed

    Spektor, B; Shamir, J

    1995-07-01

    A compact wave-front sensor is implemented by an array of two-beam common path inversion interferometers. Each element of the array consists of two Fresnel lenses in a confocal configuration. The wave-front data can be extracted from a superposition of the zero-order undiffracted wave and the twice-diffracted first-order wave. The result is a high-sensitivity, compact, and stable interferometric wave-front sensor.

  18. Specificity analysis of protein lysine methyltransferases using SPOT peptide arrays.

    PubMed

    Kudithipudi, Srikanth; Kusevic, Denis; Weirich, Sara; Jeltsch, Albert

    2014-11-29

    Lysine methylation is an emerging post-translation modification and it has been identified on several histone and non-histone proteins, where it plays crucial roles in cell development and many diseases. Approximately 5,000 lysine methylation sites were identified on different proteins, which are set by few dozens of protein lysine methyltransferases. This suggests that each PKMT methylates multiple proteins, however till now only one or two substrates have been identified for several of these enzymes. To approach this problem, we have introduced peptide array based substrate specificity analyses of PKMTs. Peptide arrays are powerful tools to characterize the specificity of PKMTs because methylation of several substrates with different sequences can be tested on one array. We synthesized peptide arrays on cellulose membrane using an Intavis SPOT synthesizer and analyzed the specificity of various PKMTs. Based on the results, for several of these enzymes, novel substrates could be identified. For example, for NSD1 by employing peptide arrays, we showed that it methylates K44 of H4 instead of the reported H4K20 and in addition H1.5K168 is the highly preferred substrate over the previously known H3K36. Hence, peptide arrays are powerful tools to biochemically characterize the PKMTs.

  19. Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays

    PubMed Central

    Kudithipudi, Srikanth; Kusevic, Denis; Weirich, Sara; Jeltsch, Albert

    2014-01-01

    Lysine methylation is an emerging post-translation modification and it has been identified on several histone and non-histone proteins, where it plays crucial roles in cell development and many diseases. Approximately 5,000 lysine methylation sites were identified on different proteins, which are set by few dozens of protein lysine methyltransferases. This suggests that each PKMT methylates multiple proteins, however till now only one or two substrates have been identified for several of these enzymes. To approach this problem, we have introduced peptide array based substrate specificity analyses of PKMTs. Peptide arrays are powerful tools to characterize the specificity of PKMTs because methylation of several substrates with different sequences can be tested on one array. We synthesized peptide arrays on cellulose membrane using an Intavis SPOT synthesizer and analyzed the specificity of various PKMTs. Based on the results, for several of these enzymes, novel substrates could be identified. For example, for NSD1 by employing peptide arrays, we showed that it methylates K44 of H4 instead of the reported H4K20 and in addition H1.5K168 is the highly preferred substrate over the previously known H3K36. Hence, peptide arrays are powerful tools to biochemically characterize the PKMTs. PMID:25489813

  20. Preparation of Single-cell Suspensions for Cytofluorimetric Analysis from Different Mouse Skin Regions.

    PubMed

    Broggi, Achille; Cigni, Clara; Zanoni, Ivan; Granucci, Francesca

    2016-04-20

    The skin is a barrier organ that interacts with the external environment. Being continuously exposed to potential microbial invasion, the dermis and epidermis home a variety of immune cells in both homeostatic and inflammatory conditions. Tools to obtain skin cell release for cytofluorimetric analyses are, therefore, very useful in order to study the complex network of immune cells residing in the skin and their response to microbial stimuli. Here, we describe an efficient methodology for the digestion of mouse skin to rapidly and efficiently obtain single-cell suspensions. This protocol allows maintenance of maximum cell viability without compromising surface antigen expression. We also describe how to take and digest skin samples from different anatomical locations, such as the ear, trunk, tail, and footpad. The obtained suspensions are then stained and analyzed by flow cytometry to discriminate between different leukocyte populations.

  1. Random vibrations of quadratic damping systems. [optimum damping analysis for automobile suspension system

    NASA Technical Reports Server (NTRS)

    Sireteanu, T.

    1974-01-01

    An oscillating system with quadratic damping subjected to white noise excitation is replaced by a nonlinear, statistically equivalent system for which the associated Fokker-Planck equation can be exactly solved. The mean square responses are calculated and the optimum damping coefficient is determined with respect to the minimum mean square acceleration criteria. An application of these results to the optimization of automobile suspension damping is given.

  2. Analysis of backwashing efficiency in dead-end hollow-fibre ultrafiltration of anaerobic suspensions.

    PubMed

    Vera, Luisa; González, Enrique; Ruigómez, Ignacio; Gómez, Jenniffer; Delgado, Sebastián

    2015-11-01

    A novel dead-end mode operation for filtering anaerobic suspensions was investigated. In this mode, the filtration system automatically adjusted backwashing frequency to a preselected transmembrane pressure set-point. This paper discusses the effectiveness of the backwashing conditions on membrane fouling. Anaerobic suspensions from a conventional wastewater treatment plant digester were used as model suspensions for the trials carried out at lab-scale. Gas sparging aided backwashing significantly enhanced membrane cleaning efficiency. No effect of gas sparging on internal fouling was detected. Also, the cleaning efficiency linearly decreased with permeate flux. Nevertheless, due to a high increase in the reversible fouling, a reasonable net permeate flux (7.2-6.8 L/h m(2)) can be achieved when intermediate fluxes (12-16 L/h m(2)) were imposed and the higher transmembrane pressure set-point value (50 kPa) was applied. Both backwashing duration and flux exhibited similar influence on cake fouling removal for a given volume of permeate produced.

  3. Design and analysis of a shock absorber with variable moment of inertia for passive vehicle suspensions

    NASA Astrophysics Data System (ADS)

    Xu, Tongyi; Liang, Ming; Li, Chuan; Yang, Shuai

    2015-10-01

    A two-terminal mass (TTM) based vibration absorber with variable moment of inertia (VMI) for passive vehicle suspension is proposed. The VMI of the system is achieved by the motion of sliders embedded in a hydraulic driven flywheel. The moment of inertia increases in reaction to strong vertical vehicle oscillations and decreases for weak vertical oscillations. The hydraulic mechanism of the system converts the relative linear motion between the two terminals of the suspension into rotating motion of the flywheel. In the case of stronger vehicle vertical oscillation, the sliders inside the flywheel move away from the center of the flywheel because of the centrifugal force, hence yielding higher moment of inertia. The opposite is true in the case of weaker vehicle oscillation. As such, the moment of inertia adjusts itself adaptively in response to the road conditions. The performance of the proposed TTM-VMI absorber has been analyzed via dynamics modeling and simulation and further examined by experiments. In comparison to its counterpart with constant moment of inertia, the proposed VMI system offers faster response, better road handling and safety, improved ride comfort, and reduced suspension deflection except in the case of sinusoidal excitations.

  4. Numerical Analysis of Multicomponent Suspension Droplets in High-Velocity Flame Spray Process

    NASA Astrophysics Data System (ADS)

    Gozali, Ebrahim; Mahrukh, Mahrukh; Gu, Sai; Kamnis, Spyros

    2014-08-01

    The liquid feedstock or suspension as a different mixture of liquid fuel ethanol and water is numerically studied in high-velocity suspension flame spray (HVSFS) process, and the results are compared for homogenous liquid feedstock of ethanol and water. The effects of mixture on droplet aerodynamic breakup, evaporation, combustion, and gas dynamics of HVSFS process are thoroughly investigated. The exact location where the particle heating is initiated (above the carrier liquid boiling point) can be controlled by increasing the water content in the mixture. In this way, the particle inflight time in the high-temperature gas regions can be adjusted avoiding adverse effects from surface chemical transformations. The mixture is modeled as a multicomponent droplet, and a convection/diffusion model, which takes into account the convective flow of evaporating material from droplet surface, is used to simulate the suspension evaporation. The model consists of several sub-models that include premixed combustion of propane-oxygen, non-premixed ethanol-oxygen combustion, modeling of multicomponent droplet breakup and evaporation, as well as heat and mass transfer between liquid droplets and gas phase.

  5. Depletion stabilization in nanoparticle-polymer suspensions: multi-length-scale analysis of microstructure.

    PubMed

    Kim, Sunhyung; Hyun, Kyu; Moon, Joo Yong; Clasen, Christian; Ahn, Kyung Hyun

    2015-02-17

    We study the mechanism of depletion stabilization and the resultant microstructure of aqueous suspensions of nanosized silica and poly(vinyl alcohol) (PVA). Rheology, small-angle light scattering (SALS), and small-angle X-ray scattering (SAXS) techniques enable us to analyze the microstructure at broad length scale from single particle size to the size of a cluster of aggregated particles. As PVA concentration increases, the microstructure evolves from bridging flocculation, steric stabilization, depletion flocculation to depletion stabilization. To our surprise, when depletion stabilization occurs, the suspension shows the stabilization at the cluster length scale, while maintaining fractal aggregates at the particle length scale. This sharply contrasts previously reported studies on the depletion stabilization of microsized particle and polymer suspensions, which exhibits the stabilization at the particle length scale. On the basis of the evaluation of depletion interaction, we propose that the depletion energy barrier exists between clusters rather than particles due to the comparable size of silica particle and the radius gyration of PVA.

  6. Design and Analysis of the Warm-To Suspension Links for Jefferson Lab's 11 Gev/c Super High Momentum Spectrometer

    NASA Astrophysics Data System (ADS)

    Sun, E.; Brindza, P.; Lassiter, S.; Fowler, M.

    2010-04-01

    This paper describes design and analysis performed for the warm-to-cold suspension links of the warm iron yoke superconducting quadrupole magnets, and superconducting dipole magnet. The results of investigation of titanium Ti-6Al-4V and Nitronic 50 stainless steel for the suspension links to support the cold mass, preloads, forces due to cryogenic temperature, and imbalanced magnetic forces from misalignments are presented. Allowable stresses at normal-case scenarios and worst-case scenarios, space constraints, and heat leak considerations are discussed. Principles of the ASME Pressure Vessel Code were used to determine allowable stresses. Optimal angles of the suspension links were obtained by calculation and finite element methods. The stress levels of suspension links at multiple scenarios are presented, discussed, and compared with the allowable stresses.

  7. Microchannel-free collection and single-cell isolation of yeast cells in a suspension using liquid standing wave

    NASA Astrophysics Data System (ADS)

    Matsutani, Akihiro; Takada, Ayako

    2016-11-01

    We demonstrate a microchannel-free collection method at nodes of liquid standing waves by the vertical vibration of a suspension including yeast cells. The pattern formation of the collection of cells using standing waves in a suspension was investigated by varying the frequency and waveform of vibrations. The single-cell isolation of yeast cells was achieved using a microenclosure array set at the nodes. In addition, we succeeded in the microchannel-free collection of yeast cells in a suspension, where patterns were formed by tapping vibration. The proposed technique is very simple and we believe that it will be useful for single-cell analysis and investigation.

  8. A Rayleigh Wave Analysis at the DESERT Broadband Array

    NASA Astrophysics Data System (ADS)

    Laske, G.; Desert Team

    2003-12-01

    A variety of geophysical experiments conducted in the 2000/2001 DESERT project in Israel, Palestine and Jordan provided a rich palette of datasets to examine the crust and uppermost mantle beneath one of Earth's most prominent fault systems, the Dead Sea Transform system (DST). As part of the passive seismic component, thirty broad--band sensors were deployed across the DST for roughly one year. During this deployment we recorded 115 teleseismic earthquakes that are suitable for a fundamental mode surface wave analysis at intermediate periods (20-120s). Analyzing arrival angle measurements we are able to determine the orientation of the horizontal components to within one degree. Some sensors were misaligned by nearly 10 degrees which is confirmed by the station operators (e.g. one station was oriented parallel to a road because the compass broke). The frequency--dependent Rayleigh wave phase at each station is measured with respect to each other rather than relative to a synthetic. This results in a much more precise dataset than what is common for global dispersion datasets. A preliminary analysis reveals a seismically fast but thin lid (about 80~km) to the west of the DST. Toward the east, shallow seismic velocities are low while a deeper low velocity zone is not detected. This contradicts the currently favored thermo-mechanical model for the DST that predicts lithospheric thinning toward the east. Unfortunately, the distribution of sensors at the array was not ideal for a surface wave analysis. The stations west of the DST were equipped with true broad-band sensors (Streckeisen STS-2 or Guralp CMT-3T), while the stations east of the DST were equipped with ''wideband'' Guralp-40T that are considerably noisy at periods longer than 40s. We we able to measure dispersion down to 80~s, sometimes below that, depending on the size of the earthquake, but not for all earthquakes. Dispersion at these periods are needed to trace the bottom of the lithosphere. The apparent

  9. Array Independent Component Analysis with Application to Remote Sensing

    NASA Astrophysics Data System (ADS)

    Kukuyeva, Irina A.

    2012-11-01

    There are three ways to learn about an object: from samples taken directly from the site, from simulation studies based on its known scientific properties, or from remote sensing images. All three are carried out to study Earth and Mars. Our goal, however, is to learn about the second largest storm on Jupiter, called the White Oval, whose characteristics are unknown to this day. As Jupiter is a gas giant and hundreds of millions of miles away from Earth, we can only make inferences about the planet from retrieval algorithms and remotely sensed images. Our focus is to find latent variables from the remotely sensed data that best explain its underlying atmospheric structure. Principal Component Analysis (PCA) is currently the most commonly employed technique to do so. For a data set with more than two modes, this approach fails to account for all of the variable interactions, especially if the distribution of the variables is not multivariate normal; an assumption that is rarely true of multispectral images. The thesis presents an overview of PCA along with the most commonly employed decompositions in other fields: Independent Component Analysis, Tucker-3 and CANDECOMP/PARAFAC and discusses their limitations in finding unobserved, independent structures in a data cube. We motivate the need for a novel dimension reduction technique that generalizes existing decompositions to find latent, statistically independent variables for one side of a multimodal (number of modes greater than two) data set while accounting for the variable interactions with its other modes. Our method is called Array Independent Component Analysis (AICA). As the main question of any decomposition is how to select a small number of latent variables that best capture the structure in the data, we extend the heuristic developed by Ceulemans and Kiers in [10] to aid in model selection for the AICA framework. The effectiveness of each dimension reduction technique is determined by the degree of

  10. Coherence analysis using canonical coordinate decomposition with applications to sparse processing and optimal array deployment

    NASA Astrophysics Data System (ADS)

    Azimi-Sadjadi, Mahmood R.; Pezeshki, Ali; Wade, Robert L.

    2004-09-01

    Sparse array processing methods are typically used to improve the spatial resolution of sensor arrays for the estimation of direction of arrival (DOA). The fundamental assumption behind these methods is that signals that are received by the sparse sensors (or a group of sensors) are coherent. However, coherence may vary significantly with the changes in environmental, terrain, and, operating conditions. In this paper canonical correlation analysis is used to study the variations in coherence between pairs of sub-arrays in a sparse array problem. The data set for this study is a subset of an acoustic signature data set, acquired from the US Army TACOM-ARDEC, Picatinny Arsenal, NJ. This data set is collected using three wagon-wheel type arrays with five microphones. The results show that in nominal operating conditions, i.e. no extreme wind noise or masking effects by trees, building, etc., the signals collected at different sensor arrays are indeed coherent even at distant node separation.

  11. A Unified Approach to the Analysis and Synthesis of Systolic Arrays.

    DTIC Science & Technology

    1985-04-01

    ANALYSIS AND SYNTHESIS OF SYSTOLIC ARRAYS... Analysis and Synthesis of Systolic Arrays N/A N/A N/A N/A 12. PERSONAL AUTHOR($) Hornick, Scot Wayne 13&. TYP OF REPORT K-J 1131L TIME COVERIO 14. OATS OF...frame- work to unify the analysis and synthesis of systolic networks. We describe a class of transformations on systolic networks that alter

  12. Array2BIO: A Comprehensive Suite of Utilities for the Analysis of Microarray Data

    SciTech Connect

    Loots, G G; Chain, P G; Mabery, S; Rasley, A; Garcia, E; Ovcharenko, I

    2006-02-13

    We have developed an integrative and automated toolkit for the analysis of Affymetrix microarray data, named Array2BIO. It identifies groups of coexpressed genes using two complementary approaches--comparative analysis of signal versus control microarrays and clustering analysis of gene expression across different conditions. The identified genes are assigned to functional categories based on the Gene Ontology classification, and a detection of corresponding KEGG protein interaction pathways. Array2BIO reliably handles low-expressor genes and provides a set of statistical methods to quantify the odds of observations, including the Benjamini-Hochberg and Bonferroni multiple testing corrections. Automated interface with the ECR Browser provides evolutionary conservation analysis of identified gene loci while the interconnection with Creme allows high-throughput analysis of human promoter regions and prediction of gene regulatory elements that underlie the observed expression patterns. Array2BIO is publicly available at http://array2bio.dcode.org.

  13. Stability Analysis of the Buck-Boost Type Solar Array Regulator

    NASA Astrophysics Data System (ADS)

    Yang, Jeong-Hwan; Yoon, Seok-Teak; Park, Hee-Sung; Park, Sung-Woo; Koo, Ja-Chun; Jang, Jin-Baek; Lee, Sang-Kon

    2014-08-01

    The SAR (Solar Array Regulator) is different from a general DC-DC Converter. The input of the SAR is connected to the solar array and the output is connected to the battery. So, the output voltage of the SAR is constant and the input voltage of the SAR is variable. And the solar array current which is the SAR input current is variable according to the solar array voltage. Therefore, the SAR is influenced by the electrical characteristic of the solar array. For these reasons, a small signal model for a general DC-DC converter cannot be applied to the SAR for the stability analysis. In this paper, the small signal model of the BUCK-BOOST type SAR (BBSAR) is introduced and its transfer functions are induced. Using small signal transfer functions, the stability analysis is performed and its results are compared to the simulation result.

  14. Biomedical analysis of rat body hair after hindlimb suspension for 14 days

    NASA Astrophysics Data System (ADS)

    Terada, Masahiro; Kawano, Fuminori; Ishioka, Noriaki; Higashibata, Akira; Majima, Hideyuki J.; Yamazaki, Takashi; Watanabe-Asaka, Tomomi; Niihori, Maki; Nakao, Reiko; Yamada, Shin; Mukai, Chiaki; Ohira, Yoshinobu

    2012-04-01

    The levels of 26 minerals in rat body hair were analyzed in control and hindlimb-suspended Wistar Hannover rats (n=5 each). We quantified the levels of 22 minerals in this experiment. However, we were unable to measure the levels of 4 minerals (Be, V, Cd, and Hg) quantitatively because they were below the limit of detection. Of the 22 quantified, the levels of 19 minerals were not significantly different between control and hindlimb-suspended groups. The levels of 3 minerals (Pb, Cr, and Al) tended to be higher in the hindlimb-suspended group than in the control group; however, this difference was not significant. The concentrations of 3 other minerals (I, K, and Mg) were significantly different between the 2 groups. The iodine (I) level was 58.2% higher in the hindlimb-suspended group than in the control group (P<0.05). Potassium (K) and magnesium (Mg) levels were 55.2% and 20.4% lower, respectively, in the experimental group (P<0.05 in both cases). These results indicate that a physiological change in mineral metabolism resulting from physical or mental stress, such as hindlimb suspension, is reflected in body hair. The Japan Aerospace Exploration Agency (JAXA) has initiated a human research study to investigate the effects of long-term space flight on gene expression and mineral metabolism by analyzing hair samples of astronauts who stayed in the International Space Station (ISS) for 6 months. We believe that hindlimb suspension for 14 days can simulate the effects of an extremely severe environment, such as space flight, because the hindlimb suspension model elicits a rapid physiological change in skeletal muscle, bone, and fluid shift even in the short term. These results also suggest that we can detect various effects on the body by analyzing the human scalp hair shaft.

  15. [Particle Size and Number Density Online Analysis for Particle Suspension with Polarization-Differentiation Elastic Light Scattering Spectroscopy].

    PubMed

    Chen, Wei-kang; Fang, Hui

    2016-03-01

    The basic principle of polarization-differentiation elastic light scattering spectroscopy based techniques is that under the linear polarized light incidence, the singlely scattered light from the superficial biological tissue and diffusively scattered light from the deep tissue can be separated according to the difference of polarization characteristics. The novel point of the paper is to apply this method to the detection of particle suspension and, to realize the simultaneous measurement of its particle size and number density in its natural status. We design and build a coaxial cage optical system, and measure the backscatter signal at a specified angle from a polystyrene microsphere suspension. By controlling the polarization direction of incident light with a linear polarizer and adjusting the polarization direction of collected light with another linear polarizer, we obtain the parallel polarized elastic light scattering spectrum and cross polarized elastic light scattering spectrum. The difference between the two is the differential polarized elastic light scattering spectrum which include only the single scattering information of the particles. We thus compare this spectrum to the Mie scattering calculation and extract the particle size. We then also analyze the cross polarized elastic light scattering spectrum by applying the particle size already extracted. The analysis is based on the approximate expressions taking account of light diffusing, from which we are able to obtain the number density of the particle suspension. We compare our experimental outcomes with the manufacturer-provided values and further analyze the influence of the particle diameter standard deviation on the number density extraction, by which we finally verify the experimental method. The potential applications of the method include the on-line particle quality monitoring for particle manufacture as well as the fat and protein density detection of milk products.

  16. Digital controller design: Analysis of the annular suspension pointing system. [analog controllers with feedback

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.

    1978-01-01

    The analog controllers of the annular suspension pointing system are designed for control of the chi, phi sub 1, and phi sub 2 bandwidth dynamics through decoupling and pole placement. Since it is virtually impossible to find an equivalent bandwidth of the overall system and establish a general eigenvalue requirement for the system, the subsystem dynamics are decoupled through state feedback and the poles are placed simultaneously to realize the desired bandwidths for the three system components. Decoupling and pole placement are also used to design the closed-loop digital system through approximation.

  17. Nonlinear analysis and performance evaluation of the Annular Suspension and Pointing System (ASPS)

    NASA Technical Reports Server (NTRS)

    Joshi, S. M.

    1978-01-01

    The Annular Suspension and Pointing System (ASPS) can provide high accurate fine pointing for a variety of solar-, stellar-, and Earth-viewing scientific instruments during space shuttle orbital missions. In this report, a detailed nonlinear mathematical model is developed for the ASPS/Space Shuttle system. The equations are augmented with nonlinear models of components such as magnetic actuators and gimbal torquers. Control systems and payload attitude state estimators are designed in order to obtain satisfactory pointing performance, and statistical pointing performance is predicted in the presence of measurement noise and disturbances.

  18. CRSP Hyperspectral Stripe Array Targets: Preliminary Results and Analysis

    NASA Technical Reports Server (NTRS)

    Terrie, Gregory; Jenner, Jeff; Tate, Steve; Muston, Shaun; Schaefer, Jason; Grant, Brennan; Sellers, Richard

    2000-01-01

    Objectives of this program: Assess the capability of a spaceborne hyperspectral sensor/algorithm system to perform target detection; Provide information to guide the design and construction of surrogate targets and stripe arrays; Target development cost of less than 50,000.

  19. Analysis and simulation tools for solar array power systems

    NASA Astrophysics Data System (ADS)

    Pongratananukul, Nattorn

    This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the performance of an actual digital controller implemented in programmable hardware such as a DSP processor, while the entire solar array including the DC-DC power converter is modeled in software algorithms running on a computer. This "virtual plant" allows developing and debugging code for the digital controller, and also to improve the control algorithm. One important task in solar arrays is to track the maximum power point on the array in order to maximize the power that can be delivered. Digital controllers implemented with programmable processors are particularly attractive for this task because sophisticated tracking algorithms can be implemented and revised when needed to optimize their performance. The proposed co-simulation tools are thus very valuable in developing and optimizing the control algorithm, before the system is built. Examples that demonstrate the effectiveness of the proposed methodologies are presented. The proposed simulation tools are also valuable in the design of multi-channel arrays. In the specific system that we have designed and tested, the control algorithm is implemented on a single digital signal processor. In each of the channels the maximum power point is tracked individually. In the prototype we built, off

  20. Thermal correlation analysis of a long-span suspension bridge static responses

    NASA Astrophysics Data System (ADS)

    Zhou, Linren; Chen, Lan; Xia, Yong; Brownjohn, James M. W.

    2016-04-01

    Harsh service environment degenerates the performance of bridges even leads to catastrophic collapse. Structural temperature has been widely recognized as one of the most negative environmental effects on bridges. The structural responses are deeply affected by the variation and distribution of temperatures on bridges. Therefore, identifying the correlations between them is a significant issue for structural safety assessment. In this study, the relationships between the temperature induced static response and the surrounding weather factors are investigated based on the long-term field measurements of a long-span suspension bridge. The correlations of the meteorological parameters between the bridge filed and the nearby weather station, and the relations of structural static responses to the air temperature, are investigated. The results indicate that relationships of meteorological parameters between nearby weather station and the bridge field can be predicted. The correlation between the static responses and the air temperature and is remarkable with high correlation coefficient. The conclusions are expected to provide reference for the design and evaluation of longspan suspension bridges.

  1. Computational Analysis of Static and Dynamic Behaviour of Magnetic Suspensions and Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P. (Editor); Groom, Nelson J.

    1996-01-01

    Static modelling of magnetic bearings is often carried out using magnetic circuit theory. This theory cannot easily include nonlinear effects such as magnetic saturation or the fringing of flux in air-gaps. Modern computational tools are able to accurately model complex magnetic bearing geometries, provided some care is exercised. In magnetic suspension applications, the magnetic fields are highly three-dimensional and require computational tools for the solution of most problems of interest. The dynamics of a magnetic bearing or magnetic suspension system can be strongly affected by eddy currents. Eddy currents are present whenever a time-varying magnetic flux penetrates a conducting medium. The direction of flow of the eddy current is such as to reduce the rate-of-change of flux. Analytic solutions for eddy currents are available for some simplified geometries, but complex geometries must be solved by computation. It is only in recent years that such computations have been considered truly practical. At NASA Langley Research Center, state-of-the-art finite-element computer codes, 'OPERA', 'TOSCA' and 'ELEKTRA' have recently been installed and applied to the magnetostatic and eddy current problems. This paper reviews results of theoretical analyses which suggest general forms of mathematical models for eddy currents, together with computational results. A simplified circuit-based eddy current model proposed appears to predict the observed trends in the case of large eddy current circuits in conducting non-magnetic material. A much more difficult case is seen to be that of eddy currents in magnetic material, or in non-magnetic material at higher frequencies, due to the lower skin depths. Even here, the dissipative behavior has been shown to yield at least somewhat to linear modelling. Magnetostatic and eddy current computations have been carried out relating to the Annular Suspension and Pointing System, a prototype for a space payload pointing and vibration

  2. Performance analysis of structured gradient algorithm. [for adaptive beamforming linear arrays

    NASA Technical Reports Server (NTRS)

    Godara, Lal C.

    1990-01-01

    The structured gradient algorithm uses a structured estimate of the array correlation matrix (ACM) to estimate the gradient required for the constrained least-mean-square (LMS) algorithm. This structure reflects the structure of the exact array correlation matrix for an equispaced linear array and is obtained by spatial averaging of the elements of the noisy correlation matrix. In its standard form the LMS algorithm does not exploit the structure of the array correlation matrix. The gradient is estimated by multiplying the array output with the receiver outputs. An analysis of the two algorithms is presented to show that the covariance of the gradient estimated by the structured method is less sensitive to the look direction signal than that estimated by the standard method. The effect of the number of elements on the signal sensitivity of the two algorithms is studied.

  3. Crosstalk analysis of silicon-on-insulator nanowire-arrayed waveguide grating

    NASA Astrophysics Data System (ADS)

    Li, Kai-Li; An, Jun-Ming; Zhang, Jia-Shun; Wang, Yue; Wang, Liang-Liang; Li, Jian-Guang; Wu, Yuan-Da; Yin, Xiao-Jie; Hu, Xiong-Wei

    2016-12-01

    The factors influencing the crosstalk of silicon-on-insulator (SOI) nanowire arrayed waveguide grating (AWG) are analyzed using the transfer function method. The analysis shows that wider and thicker arrayed waveguides, outsider fracture of arrayed waveguide, and larger channel space, could mitigate the deterioration of crosstalk. The SOI nanowire AWGs with different arrayed waveguide widths are fabricated by using deep ultraviolet lithography (DUV) and inductively coupled plasma etching (ICP) technology. The measurement results show that the crosstalk performance is improved by about 7 dB through adopting 800 nm arrayed waveguide width. Project supported by the National High Technology Research and Development Program of China (Grant No. 2015AA016902), the National Natural Science Foundation of China (Grant Nos. 61274047, 61435013, 61307034, and 61405188), and the National Key Research and Development Program of China (Grant No. 2016YFB0402504).

  4. Exon array data analysis using Affymetrix power tools and R statistical software

    PubMed Central

    2011-01-01

    The use of microarray technology to measure gene expression on a genome-wide scale has been well established for more than a decade. Methods to process and analyse the vast quantity of expression data generated by a typical microarray experiment are similarly well-established. The Affymetrix Exon 1.0 ST array is a relatively new type of array, which has the capability to assess expression at the individual exon level. This allows a more comprehensive analysis of the transcriptome, and in particular enables the study of alternative splicing, a gene regulation mechanism important in both normal conditions and in diseases. Some aspects of exon array data analysis are shared with those for standard gene expression data but others present new challenges that have required development of novel tools. Here, I will introduce the exon array and present a detailed example tutorial for analysis of data generated using this platform. PMID:21498550

  5. Exon array data analysis using Affymetrix power tools and R statistical software.

    PubMed

    Lockstone, Helen E

    2011-11-01

    The use of microarray technology to measure gene expression on a genome-wide scale has been well established for more than a decade. Methods to process and analyse the vast quantity of expression data generated by a typical microarray experiment are similarly well-established. The Affymetrix Exon 1.0 ST array is a relatively new type of array, which has the capability to assess expression at the individual exon level. This allows a more comprehensive analysis of the transcriptome, and in particular enables the study of alternative splicing, a gene regulation mechanism important in both normal conditions and in diseases. Some aspects of exon array data analysis are shared with those for standard gene expression data but others present new challenges that have required development of novel tools. Here, I will introduce the exon array and present a detailed example tutorial for analysis of data generated using this platform.

  6. ATM solar array in-flight performance analysis

    NASA Technical Reports Server (NTRS)

    Thornton, J. P.; Crabtree, L. W.

    1974-01-01

    The physical and electrical characteristics of the Apollo Telescope Mount (ATM) solar array are described and in-flight performance data are analyzed and compared with predicted results. Two solar cell module configurations were used. Type I module consists of 228 2 x 6 cm solar cells with two cells in parallel and 114 cells in series. Type II modules contain 684 2 x 2 cm cells with six cells in parallel and 114 cells in series. A different interconnection scheme was used for each type. Panels using type II modules with mesh interconnect system performed marginally better than those using type I module with loop interconnect system. The average degradation rate for the ATM array was 8.2% for a 271-day mission.

  7. Performance Analysis for Lateral-Line-Inspired Sensor Arrays

    DTIC Science & Technology

    2011-06-01

    frequency is encoded in the nerve fibers connected to the lateral line [10], indicating that at least some high level information about vortices is being...Mogdans. Responses to dipole stimuli of anterior lateral line nerve fibres in goldfish, carassius auratus, under still and running water conditions...M. Humphreys. Wall-pressure-array measure- ments beneath a separating/ reattaching flow region. Physics of Fluids, 15(3):706–717, March 2003. [37

  8. Analysis of modified SMI method for adaptive array weight control

    NASA Technical Reports Server (NTRS)

    Dilsavor, R. L.; Moses, R. L.

    1989-01-01

    An adaptive array is applied to the problem of receiving a desired signal in the presence of weak interference signals which need to be suppressed. A modification, suggested by Gupta, of the sample matrix inversion (SMI) algorithm controls the array weights. In the modified SMI algorithm, interference suppression is increased by subtracting a fraction F of the noise power from the diagonal elements of the estimated covariance matrix. Given the true covariance matrix and the desired signal direction, the modified algorithm is shown to maximize a well-defined, intuitive output power ratio criterion. Expressions are derived for the expected value and variance of the array weights and output powers as a function of the fraction F and the number of snapshots used in the covariance matrix estimate. These expressions are compared with computer simulation and good agreement is found. A trade-off is found to exist between the desired level of interference suppression and the number of snapshots required in order to achieve that level with some certainty. The removal of noise eigenvectors from the covariance matrix inverse is also discussed with respect to this application. Finally, the type and severity of errors which occur in the covariance matrix estimate are characterized through simulation.

  9. Stress inversion method and analysis of GPS array data

    NASA Astrophysics Data System (ADS)

    Hori, Muneo; Iinuma, Takeshi; Kato, Teruyuki

    2008-01-01

    The stress inversion method is developed to find a stress field which satisfies the equation of equilibrium for a body in a state of plane stress. When one stress-strain relation is known and data on the strain distribution on the body and traction along the boundary are provided, the method solves a well-posed problem, which is a linear boundary value problem for Airy's stress function, with the governing equation being the Poisson equation and the boundary conditions being of the Neumann type. The stress inversion method is applied to the Global Positioning System (GPS) array data of the Japanese Islands. The stress increment distribution, which is associated with the displacement increment measured by the GPS array, is computed, and it is found that the distribution is not uniform over the islands and that some regions have a relatively large increment. The elasticity inversion method is developed as an alternative to the stress inversion method; it is based on the assumption of linear elastic deformation with unknown elastic moduli and does not need boundary traction data, which are usually difficult to measure. This method is applied to the GPS array data of a small region in Japan to which the stress inversion method is not applicable. To cite this article: M. Hori et al., C. R. Mecanique 336 (2008).

  10. Oligonucleotide Arrays vs. Metaphase-Comparative Genomic Hybridisation and BAC Arrays for Single-Cell Analysis: First Applications to Preimplantation Genetic Diagnosis for Robertsonian Translocation Carriers

    PubMed Central

    Ramos, Laia; del Rey, Javier; Daina, Gemma; García-Aragonés, Manel; Armengol, Lluís; Fernandez-Encinas, Alba; Parriego, Mònica; Boada, Montserrat; Martinez-Passarell, Olga; Martorell, Maria Rosa; Casagran, Oriol; Benet, Jordi; Navarro, Joaquima

    2014-01-01

    Comprehensive chromosome analysis techniques such as metaphase-Comparative Genomic Hybridisation (CGH) and array-CGH are available for single-cell analysis. However, while metaphase-CGH and BAC array-CGH have been widely used for Preimplantation Genetic Diagnosis, oligonucleotide array-CGH has not been used in an extensive way. A comparison between oligonucleotide array-CGH and metaphase-CGH has been performed analysing 15 single fibroblasts from aneuploid cell-lines and 18 single blastomeres from human cleavage-stage embryos. Afterwards, oligonucleotide array-CGH and BAC array-CGH were also compared analysing 16 single blastomeres from human cleavage-stage embryos. All three comprehensive analysis techniques provided broadly similar cytogenetic profiles; however, non-identical profiles appeared when extensive aneuploidies were present in a cell. Both array techniques provided an optimised analysis procedure and a higher resolution than metaphase-CGH. Moreover, oligonucleotide array-CGH was able to define extra segmental imbalances in 14.7% of the blastomeres and it better determined the specific unbalanced chromosome regions due to a higher resolution of the technique (≈20 kb). Applicability of oligonucleotide array-CGH for Preimplantation Genetic Diagnosis has been demonstrated in two cases of Robertsonian translocation carriers 45,XY,der(13;14)(q10;q10). Transfer of euploid embryos was performed in both cases and pregnancy was achieved by one of the couples. This is the first time that an oligonucleotide array-CGH approach has been successfully applied to Preimplantation Genetic Diagnosis for balanced chromosome rearrangement carriers. PMID:25415307

  11. Oligonucleotide arrays vs. metaphase-comparative genomic hybridisation and BAC arrays for single-cell analysis: first applications to preimplantation genetic diagnosis for Robertsonian translocation carriers.

    PubMed

    Ramos, Laia; del Rey, Javier; Daina, Gemma; García-Aragonés, Manel; Armengol, Lluís; Fernandez-Encinas, Alba; Parriego, Mònica; Boada, Montserrat; Martinez-Passarell, Olga; Martorell, Maria Rosa; Casagran, Oriol; Benet, Jordi; Navarro, Joaquima

    2014-01-01

    Comprehensive chromosome analysis techniques such as metaphase-Comparative Genomic Hybridisation (CGH) and array-CGH are available for single-cell analysis. However, while metaphase-CGH and BAC array-CGH have been widely used for Preimplantation Genetic Diagnosis, oligonucleotide array-CGH has not been used in an extensive way. A comparison between oligonucleotide array-CGH and metaphase-CGH has been performed analysing 15 single fibroblasts from aneuploid cell-lines and 18 single blastomeres from human cleavage-stage embryos. Afterwards, oligonucleotide array-CGH and BAC array-CGH were also compared analysing 16 single blastomeres from human cleavage-stage embryos. All three comprehensive analysis techniques provided broadly similar cytogenetic profiles; however, non-identical profiles appeared when extensive aneuploidies were present in a cell. Both array techniques provided an optimised analysis procedure and a higher resolution than metaphase-CGH. Moreover, oligonucleotide array-CGH was able to define extra segmental imbalances in 14.7% of the blastomeres and it better determined the specific unbalanced chromosome regions due to a higher resolution of the technique (≈ 20 kb). Applicability of oligonucleotide array-CGH for Preimplantation Genetic Diagnosis has been demonstrated in two cases of Robertsonian translocation carriers 45,XY,der(13;14)(q10;q10). Transfer of euploid embryos was performed in both cases and pregnancy was achieved by one of the couples. This is the first time that an oligonucleotide array-CGH approach has been successfully applied to Preimplantation Genetic Diagnosis for balanced chromosome rearrangement carriers.

  12. A preliminary analysis of a diode array for densitometry

    NASA Astrophysics Data System (ADS)

    Janes, K. A.

    1984-07-01

    A diode-array based image digitizer manufactured by the Eikonix Corp. was tested to see if it can be adapted to the exacting requirements of astronomical densitometry. As the device is presently configured, a dynamic range of 400:1 can be achieved routinely, with a positional accuracy of 2 microns or better. An area of 2048 X 2048 pixels can be scanned in about 5 minutes. Preliminary tests indicate that several relatively simple enhancements can improve both the photometric and the positional accuracy of the device.

  13. Economic analysis of the unified heliostat array. Final report

    SciTech Connect

    Not Available

    1981-01-31

    The Unified Heliostat Array (UHA) was investigated as to cost and optical performance. Two heliostats, the Veda Industrial Heliostat (VIH) and the Repowering Heliostat were investigated in conjunction with the UHA. The UHA was found to be a viable candidate for solar thermal central receiver applications. The UHA-VIH combination was shown to provide very high flux densities and to be suitable for high temperature applications in the 1000/sup 0/K to 2000/sup 0/K range. These temperatures were shown to be achievable even with very small (1 MWt) collector fields.

  14. Analysis of Image Formation with Thinned Random Arrays

    DTIC Science & Technology

    1979-06-01

    FORCE OFFICE OF SCIENTIFIC RESEARCH Building 410 i Boiling Air Force Base , Washington, DC 20332 A ~VA Approved for public rolo~ae; UT G’ -7 7 . . . . 7...However, there is no general theory available for the algorithmic design of this class of arrays. Many of the designs to date have been based on trial- and...system. The system impulse function is directly related 14 to the pupil function by a Fourier trmnsformation: h(x,y) ff P(•,) 6 -i2T(xc+Y8) dadO . (3

  15. Analysis and modeling for thermal focal plane arrays

    NASA Astrophysics Data System (ADS)

    Tuer, T. W.; Ball, B. W.; Freeling, J. R.; Lennington, J. W.; Lindquist, G. H.

    1984-07-01

    The development of a first principles computer simulation of a generic pyroelectric thermal detector is described. Formulation of the pertinent equations (based on a thorough literature survey) is presented. This simulation incorporates a finite difference treatment of the transient three-dimensional thermal response of composite focal plane arrays, with treatments of the signal generation, readout and processing including all pertinent noise sources. A number of simplified problems having analytical solutions were treated to validate various portions of the simulation to within a few percent. Performance estimates were made for conceptual several configurations and materials.

  16. Array analysis of regional Pn and Pg wavefields from the Nevada Test Site

    SciTech Connect

    Leonard, M.A. . Dept. of Geology and Geophysics Lawrence Berkeley Lab., CA )

    1991-06-01

    Small-aperture high-frequency seismic arrays with dimensions of a few kilometers or less, can improve our ability to seismically monitor compliance with a low-yield Threshold Test Ban Treaty. This work studies the characteristics and effectiveness of array processing of the regional Pn and Pg wavefields generated by underground nuclear explosions at the Nevada Test Site. Waveform data from the explosion HARDIN (m{sub b} = 5.5) is recorded at a temporary 12-element, 3-component, 1.5 km-aperture array sited in an area of northern Nevada. The explosions VILLE (m{sub b} = 4.4) and SALUT (m{sub b} = 5.5) are recorded at two arrays sited in the Mojave desert, one a 96-element vertical-component 7 km-aperture array and the other a 155-element vertical-component 4 km-aperture array. Among the mean spectra for the m{sub b} = 5.5 events there are significant differences in low-frequency spectral amplitudes between array sites. The spectra become nearly identical beyond about 6 Hz. Spectral ratios are used to examine seismic source properties and the partitioning of energy between Pn and Pg. Frequency-wavenumber analysis at the 12-element array is used to obtain estimates of signal gain, phase velocity, and source azimuth. This analysis reveals frequency-dependent biases in velocity and azimuth of the coherent Pn and Pg arrivals. Signal correlation, the principal factor governing array performance, is examined in terms of spatial coherence estimates. The coherence is found to vary between the three sites. In all cases the coherence of Pn is greater than that for Pg. 81 refs., 92 figs., 5 tabs.

  17. Performance Analysis of a Cost-Effective Electret Condenser Microphone Directional Array

    NASA Technical Reports Server (NTRS)

    Humphreys, William M., Jr.; Gerhold, Carl H.; Zuckerwar, Allan J.; Herring, Gregory C.; Bartram, Scott M.

    2003-01-01

    Microphone directional array technology continues to be a critical part of the overall instrumentation suite for experimental aeroacoustics. Unfortunately, high sensor cost remains one of the limiting factors in the construction of very high-density arrays (i.e., arrays containing several hundred channels or more) which could be used to implement advanced beamforming algorithms. In an effort to reduce the implementation cost of such arrays, the authors have undertaken a systematic performance analysis of a prototype 35-microphone array populated with commercial electret condenser microphones. An ensemble of microphones coupling commercially available electret cartridges with passive signal conditioning circuitry was fabricated for use with the Langley Large Aperture Directional Array (LADA). A performance analysis consisting of three phases was then performed: (1) characterize the acoustic response of the microphones via laboratory testing and calibration, (2) evaluate the beamforming capability of the electret-based LADA using a series of independently controlled point sources in an anechoic environment, and (3) demonstrate the utility of an electret-based directional array in a real-world application, in this case a cold flow jet operating at high subsonic velocities. The results of the investigation revealed a microphone frequency response suitable for directional array use over a range of 250 Hz - 40 kHz, a successful beamforming evaluation using the electret-populated LADA to measure simple point sources at frequencies up to 20 kHz, and a successful demonstration using the array to measure noise generated by the cold flow jet. This paper presents an overview of the tests conducted along with sample data obtained from those tests.

  18. Correlator data analysis for the array feed compensation system

    NASA Technical Reports Server (NTRS)

    Iijima, B.; Fort, D.; Vilnrotter, V.

    1994-01-01

    The real-time array feed compensation system is currently being evaluated at DSS 13. This system recovers signal-to-noise ratio (SNR) loss due to mechanical antenna deformations by using an array of seven Ka-band (33.7-GHz) horns to collect the defocused signal fields. The received signals are downconverted and digitized, in-phase and quadrature samples are generated, and combining weights are applied before the samples are recombined. It is shown that when optimum combining weights are employed, the SNR of the combined signal approaches the sum of the channel SNR's. The optimum combining weights are estimated directly from the signals in each channel by the Real-Time Block 2 (RTB2) correlator; since it was designed for very-long-baseline interferometer (VLBI) applications, it can process broadband signals as well as tones to extract the required weight estimates. The estimation algorithms for the optimum combining weights are described for tones and broadband sources. Data recorded in correlator output files can also be used off-line to estimate combiner performance by estimating the SNR in each channel, which was done for data taken during a Jupiter track at DSS 13.

  19. Correlator data analysis for the array feed compensation system

    NASA Astrophysics Data System (ADS)

    Iijima, B.; Fort, D.; Vilnrotter, V.

    1994-05-01

    The real-time array feed compensation system is currently being evaluated at DSS 13. This system recovers signal-to-noise ratio (SNR) loss due to mechanical antenna deformations by using an array of seven Ka-band (33.7-GHz) horns to collect the defocused signal fields. The received signals are downconverted and digitized, in-phase and quadrature samples are generated, and combining weights are applied before the samples are recombined. It is shown that when optimum combining weights are employed, the SNR of the combined signal approaches the sum of the channel SNR's. The optimum combining weights are estimated directly from the signals in each channel by the Real-Time Block 2 (RTB2) correlator; since it was designed for very-long-baseline interferometer (VLBI) applications, it can process broadband signals as well as tones to extract the required weight estimates. The estimation algorithms for the optimum combining weights are described for tones and broadband sources. Data recorded in correlator output files can also be used off-line to estimate combiner performance by estimating the SNR in each channel, which was done for data taken during a Jupiter track at DSS 13.

  20. Correlator Data Analysis for the Array Feed Compensation System

    NASA Astrophysics Data System (ADS)

    Iijima, B.; Fort, D.; Vilnrotter, V.

    1994-01-01

    The real-time array feed compensation system is currently being evaluated at DSS 13. This system recovers signal-to-noise ratio (SNR) loss due to mechanical antenna deformations by using an array of seven Ka-band (33.7-GHz) horns to collect the defocused signal fields. The received signals are downconverted and digitized, in-phase and quadrature samples are generated, and combining weights are applied before the samples are recombined. It is shown that when optimum combining weights are employed, the SNR of the combined signal approaches the sum of the channel SNRs. The optimum combining weights are estimated directly from the signals in each channel by the Real-Time Block II (RTB2) correlator; since it was designed for very-long-baseline interferometer (VLBI) applications, it can process broadband signals as well as tones to extract the required weight estimates. The estimation algorithms for the optimum combining weights are described for tones and broadband sources. Data recorded in correlator output files can also be used off-line to estimate combiner performance by estimating the SNR in each channel, which was done for data taken during a Jupiter track at DSS 13.

  1. Quartz crystal microbalance (QCM) arrays for solution analysis

    SciTech Connect

    Schneider, T.W.; Frye, G.C.; Martin, S.J.; Kottenstette, R.J.; Osbourn, G.C.; Bartholomew, J.W.; Weisenbach, L.; Bohuszewicz, T.V.; Doughty, D.H.

    1997-01-01

    Quartz crystal microbalances (QCMs) are piezoelectric thickness-shear-mode resonators where the resonant frequency has long been known to vary linearly with the mass of rigid layers on the surface when the device is in contact with air. This reports summarizes the results from a Laboratory Directed Research and Development effort to use an array of QCMs to measure and identify volatile organic compounds (VOCs) in water solutions. A total of nine polymer-coated QCMs were tested with varying concentrations of twelve VOCs while frequency and damping voltage were measured. Results from these experiments were analyzed using a Sandia-developed pattern recognition technique called visually empirical region of influence (VERI) developed at Sandia. The VERI analyses of data with up to 16% and 50% sensitivity drifts were carried out on an array with six signals obtained from five sensors. The results indicate that better than 98% and 88% correct chemical recognition is maintained for the 16% and 50% drifts, respectively. These results indicate a good degree of robustness for these sensor films.

  2. Tissue matrix arrays for high throughput screening and systems analysis of cell function

    PubMed Central

    Beachley, Vince Z.; Wolf, Matthew T.; Sadtler, Kaitlyn; Manda, Srikanth S.; Jacobs, Heather; Blatchley, Michael; Bader, Joel S.; Pandey, Akhilesh; Pardoll, Drew; Elisseeff, Jennifer H.

    2015-01-01

    Cell and protein arrays have demonstrated remarkable utility in the high-throughput evaluation of biological responses; however, they lack the complexity of native tissue and organs. Here, we describe tissue extracellular matrix (ECM) arrays for screening biological outputs and systems analysis. We spotted processed tissue ECM particles as two-dimensional arrays or incorporated them with cells to generate three-dimensional cell-matrix microtissue arrays. We then investigated the response of human stem, cancer, and immune cells to tissue ECM arrays originating from 11 different tissues, and validated the 2D and 3D arrays as representative of the in vivo microenvironment through quantitative analysis of tissue-specific cellular responses, including matrix production, adhesion and proliferation, and morphological changes following culture. The biological outputs correlated with tissue proteomics, and network analysis identified several proteins linked to cell function. Our methodology enables broad screening of ECMs to connect tissue-specific composition with biological activity, providing a new resource for biomaterials research and translation. PMID:26480475

  3. Design, optimization, and analysis of a self-deploying PV tent array

    NASA Technical Reports Server (NTRS)

    Collozza, Anthony J.

    1991-01-01

    A tent shaped PV array was designed and the design was optimized for maximum specific power. In order to minimize output power variation a tent angle of 60 deg was chosen. Based on the chosen tent angle an array structure was designed. The design considerations were minimal deployment time, high reliability, and small stowage volume. To meet these considerations the array was chosen to be self-deployable, form a compact storage configuration, using a passive pressurized gas deployment mechanism. Each structural component of the design was analyzed to determine the size necessary to withstand the various forces to which it would be subjected. Through this analysis the component weights were determined. An optimization was performed to determine the array dimensions and blanket geometry which produce the maximum specific power for a given PV blanket. This optimization was performed for both lunar and Martian environmental conditions. Other factors such as PV blanket types, structural material, and wind velocity (for Mars array), were varied to determine what influence they had on the design point. The performance specifications for the array at both locations and with each type of PV blanket were determined. These specifications were calculated using the Arimid fiber composite as the structural material. The four PV blanket types considered were silicon, GaAs/Ge, GaAsCLEFT, and amorphous silicon. The specifications used for each blanket represented either present day or near term technology. For both the Moon and Mars the amorphous silicon arrays produced the highest specific power.

  4. Theory and design of compact hybrid microphone arrays on two-dimensional planes for three-dimensional soundfield analysis.

    PubMed

    Chen, Hanchi; Abhayapala, Thushara D; Zhang, Wen

    2015-11-01

    Soundfield analysis based on spherical harmonic decomposition has been widely used in various applications; however, a drawback is the three-dimensional geometry of the microphone arrays. In this paper, a method to design two-dimensional planar microphone arrays that are capable of capturing three-dimensional (3D) spatial soundfields is proposed. Through the utilization of both omni-directional and first order microphones, the proposed microphone array is capable of measuring soundfield components that are undetectable to conventional planar omni-directional microphone arrays, thus providing the same functionality as 3D arrays designed for the same purpose. Simulations show that the accuracy of the planar microphone array is comparable to traditional spherical microphone arrays. Due to its compact shape, the proposed microphone array greatly increases the feasibility of 3D soundfield analysis techniques in real-world applications.

  5. The analysis of antioxidant expression during muscle atrophy induced by hindlimb suspension in mice.

    PubMed

    Nuoc, Tran-Non; Kim, Suhee; Ahn, Sun Hee; Lee, Jin-Sil; Park, Byung-Ju; Lee, Tae-Hoon

    2017-01-01

    Oxidative stress contributes to acceleration of muscle atrophy. However, it is still not completely understood what triggers the production of reactive oxygen species (ROS) during muscle atrophy. The objective of this study was to investigate redox balance during muscle atrophy. ROS generators and antioxidants were analyzed in atrophied soleus muscles after 2 weeks of hindlimb suspension (HLS) in mice. The HLS group showed an increase in lipid peroxidation, upregulated NOX1 and NOXO1, and downregulated mitochondrial complex I subunits NDUFS5 and NDUFV2. Additionally, HLS mice demonstrated a decrease in Prdx5 and MnSOD, but an increase in GPX2 and GPX3 in both mRNA and protein levels. As expected, MnSOD activity declined in the HLS group, while GPX activity was enhanced. These results suggest that redox imbalance occurs during muscle atrophy through NOX1 activation, mitochondrial complex I deficiency, and disturbance of antioxidants. Antioxidants altered by HLS may represent potential therapeutic targets for the protection against muscle atrophy.

  6. Analysis of the ICE combiner for multiple antenna arraying

    NASA Technical Reports Server (NTRS)

    Foster, C.; Marina, M.

    1987-01-01

    The passage of the International Cometary Explorer (ICE) through the tail of comet Giacobini-Zinner took place on September 11, 1985, at approximately 11:04 GMT. The signal-to-noise ratio of the data received from the ICE spacecraft during the comet encounter was improved by arraying the 64-m antenna channels A and B (RCP and LCP) with the two 34-m antennas. Specially designed combiners were built to combine the signals received by the three antennas at the different DSN sites to ensure that the spacecraft's weak signal was received. Although the ICE spacecraft was built with a 5-W transmitter and with a small antenna designed to provide data from no farther than 1 million miles, these combiners provided enough signal margin during the encounter to receive the ICE transmitted data from within the tail of comet Giacobini-Zinner, 44 million miles from earth.

  7. Design and analysis of subwavelength plasmonic waveguide array

    NASA Astrophysics Data System (ADS)

    Dillu, Venus; Singh, Shruti; Sinha, Ravindra K.

    2011-10-01

    We examine the propagation of plasmonic TM (Transverse Modes) modes generated in the designed periodic array of silver (Ag) embedded on silicon (Si) substrate. The properties of surface plasmons are tailored by altering the size of Ag nanorods and its periodicity. Conventional waveguides cannot guide electromagnetic energy below the diffraction limit of light, which can be overcome by texturing the metal or dielectric surface. In this hybrid design we have textured the interface by placing metallic, Ag nanorods on Si substrate placed over bilayer system of glasses. This provides the missing momentum required, since SPP modes always lay beyond the light line and has shown strong confinement of light. Ag nanorods are structured at nano dimensions to control and manipulate surface plasmon polariton (SPP) propagation and thus open new possibilities in light matter interaction.

  8. Mir Cooperative Solar Array Flight Performance Data and Computational Analysis

    NASA Technical Reports Server (NTRS)

    Kerslake, Thomas W.; Hoffman, David J.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA) was developed jointly by the United States (US) and Russia to provide approximately 6 kW of photovoltaic power to the Russian space station Mir. The MCSA was launched to Mir in November 1995 and installed on the Kvant-1 module in May 1996. Since the MCSA photovoltaic panel modules (PPMs) are nearly identical to those of the International Space Station (ISS) photovoltaic arrays, MCSA operation offered an opportunity to gather multi-year performance data on this technology prior to its implementation on ISS. Two specially designed test sequences were executed in June and December 1996 to measure MCSA performance. Each test period encompassed 3 orbital revolutions whereby the current produced by the MCSA channels was measured. The temperature of MCSA PPMs was also measured. To better interpret the MCSA flight data, a dedicated FORTRAN computer code was developed to predict the detailed thermal-electrical performance of the MCSA. Flight data compared very favorably with computational performance predictions. This indicated that the MCSA electrical performance was fully meeting pre-flight expectations. There were no measurable indications of unexpected or precipitous MCSA performance degradation due to contamination or other causes after 7 months of operation on orbit. Power delivered to the Mir bus was lower than desired as a consequence of the retrofitted power distribution cabling. The strong correlation of experimental and computational results further bolsters the confidence level of performance codes used in critical ISS electric power forecasting. In this paper, MCSA flight performance tests are described as well as the computational modeling behind the performance predictions.

  9. Mir Cooperative Solar Array flight performance data and computational analysis

    SciTech Connect

    Kerslake, T.W.; Hoffman, D.J.

    1997-12-31

    The Mir Cooperative Solar Array (MCSA) was developed jointly by the United States (US) and Russia to provide approximately 6 kW of photovoltaic power to the Russian space station Mir. The MCSA was launched to Mir in November 1995 and installed on the Kvant-1 module in May 1996. Since the MCSA photovoltaic panel modules (PPMs) are nearly identical to those of the International Space Station (ISS) photovoltaic arrays, MCSA operation offered an opportunity to gather multi-year performance data on this technology prior to its implementation on ISS. Two specially designed test sequences were executed in June and December 1996 to measure MCSA performance. Each test period encompassed 3 orbital revolutions whereby the current produced by the MCSA channels was measured. The temperature of MCSA PPMs was also measured. To better interpret the MCSA flight data, a dedicated FORTRAN computer code was developed to predict the detailed thermal-electrical performance of the MCSA. Flight data compared very favorably with computational performance predictions. This indicated that the MCSA electrical performance was fully meeting pre-flight expectations. There were no measurable indications of unexpected or precipitous MCSA performance degradation due to contamination or other causes after 7 months of operation on orbit. Power delivered to the Mir bus was lower than desired as a consequence of the retrofitted power distribution cabling. The strong correlation of experimental and computational results further bolsters the confidence level of performance codes used in critical ISS electric power forecasting. In this paper, MCSA flight performance tests are described as well as the computational modeling behind the performance predictions.

  10. Objective performance analysis of spherical microphone arrays for speech enhancement in rooms.

    PubMed

    Peled, Yotam; Rafaely, Boaz

    2012-09-01

    Reverberation and noise have a significant effect on the intelligibility of speech in rooms. The detection of clear speech in highly reverberant and noisy enclosures is an extremely difficult task. Recently, spherical microphone arrays have been studied for processing of sound fields in three-dimensions, with applications ranging from acoustic analysis to speech enhancement. This paper presents the derivation of a model that facilitates the prediction of spherical array configurations that guarantee an acceptable level of speech intelligibility in reverberant and noisy environments. A spherical microphone array is employed to generate a spatial filter that maximizes speech intelligibility according to an objective measure that combines the effects of both reverberation and noise. The spherical array beamformer is designed to enhance the speech signal while minimizing noise power and maintaining robustness over a wide frequency range. The paper includes simulation and experimental studies with a comparison to speech transmission index based analysis to provide initial validation of the model. Examples are presented in which the minimum number of microphones in a spherical array can be determined from environment conditions such as reverberation time, noise level, and distance of the array to the speech source.

  11. Stochastic segmentation models for array-based comparative genomic hybridization data analysis.

    PubMed

    Lai, Tze Leung; Xing, Haipeng; Zhang, Nancy

    2008-04-01

    Array-based comparative genomic hybridization (array-CGH) is a high throughput, high resolution technique for studying the genetics of cancer. Analysis of array-CGH data typically involves estimation of the underlying chromosome copy numbers from the log fluorescence ratios and segmenting the chromosome into regions with the same copy number at each location. We propose for the analysis of array-CGH data, a new stochastic segmentation model and an associated estimation procedure that has attractive statistical and computational properties. An important benefit of this Bayesian segmentation model is that it yields explicit formulas for posterior means, which can be used to estimate the signal directly without performing segmentation. Other quantities relating to the posterior distribution that are useful for providing confidence assessments of any given segmentation can also be estimated by using our method. We propose an approximation method whose computation time is linear in sequence length which makes our method practically applicable to the new higher density arrays. Simulation studies and applications to real array-CGH data illustrate the advantages of the proposed approach.

  12. Teleseismic array analysis of upper mantle compressional velocity structure. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Walck, M. C.

    1984-01-01

    Relative array analysis of upper mantle lateral velocity variations in southern California, analysis techniques for dense data profiles, the P-wave upper mantle structure beneath an active spreading center: the Gulf of California, and the upper mantle under the Cascade ranges: a comparison with the Gulf of California are presented.

  13. Ion Trap Array-Based Systems And Methods For Chemical Analysis

    DOEpatents

    Whitten, William B [Oak Ridge, TN; Ramsey, J Michael [Knoxville, TN

    2005-08-23

    An ion trap-based system for chemical analysis includes an ion trap array. The ion trap array includes a plurality of ion traps arranged in a 2-dimensional array for initially confining ions. Each of the ion traps comprise a central electrode having an aperture, a first and second insulator each having an aperture sandwiching the central electrode, and first and second end cap electrodes each having an aperture sandwiching the first and second insulator. A structure for simultaneously directing a plurality of different species of ions out from the ion traps is provided. A spectrometer including a detector receives and identifies the ions. The trap array can be used with spectrometers including time-of-flight mass spectrometers and ion mobility spectrometers.

  14. A cross-reactive sensor array for the fluorescence qualitative analysis of heavy metal ions.

    PubMed

    Kang, Huaizhi; Lin, Liping; Rong, Mingcong; Chen, Xi

    2014-11-01

    A cross-reactive sensor array using mercaptopropionic acid modified cadmium telluride (CdTe), glutathione modified CdTe, poly(methacrylic acid) modified silver nanoclusters, bovine serum albumin modified gold nanoclusters, rhodamine derivative and calcein blue as fluorescent indicators has been designed for the detection of seven heavy metal ions (Ag(+), Hg(2+), Pb(2+), Cu(2+), Cr(3+), Mn(2+) and Cd(2+)). The discriminatory capacity of the sensor array to different heavy metal ions in different pH solutions has been tested and the results have been analyzed with linear discriminant analysis. Results showed that the sensor array could be used to qualitatively analyze the selected heavy metal ions. The array performance was also evaluated in the identification of known and unknown samples and the preliminary results suggested the promising practicability of the designed sensor assay.

  15. Suspension and Debarment Regulations

    EPA Pesticide Factsheets

    Governmentwide Nonprocurement Suspension and Debarment Guidelines and EPA Implementation. Executive Order 12549 provides for a governmentwide system of nonprocurment (grants and cooperative agreements) debarment and suspension.

  16. Reliability analysis method of a solar array by using fault tree analysis and fuzzy reasoning Petri net

    NASA Astrophysics Data System (ADS)

    Wu, Jianing; Yan, Shaoze; Xie, Liyang

    2011-12-01

    To address the impact of solar array anomalies, it is important to perform analysis of the solar array reliability. This paper establishes the fault tree analysis (FTA) and fuzzy reasoning Petri net (FRPN) models of a solar array mechanical system and analyzes reliability to find mechanisms of the solar array fault. The index final truth degree (FTD) and cosine matching function (CMF) are employed to resolve the issue of how to evaluate the importance and influence of different faults. So an improvement reliability analysis method is developed by means of the sorting of FTD and CMF. An example is analyzed using the proposed method. The analysis results show that harsh thermal environment and impact caused by particles in space are the most vital causes of the solar array fault. Furthermore, other fault modes and the corresponding improvement methods are discussed. The results reported in this paper could be useful for the spacecraft designers, particularly, in the process of redesigning the solar array and scheduling its reliability growth plan.

  17. Analysis of optical absorption in GaAs nanowire arrays.

    PubMed

    Guo, Haomin; Wen, Long; Li, Xinhua; Zhao, Zhifei; Wang, Yuqi

    2011-12-06

    In this study, the influence of the geometric parameters on the optical absorption of gallium arsenide [GaAs] nanowire arrays [NWAs] has been systematically analyzed using finite-difference time-domain simulations. The calculations reveal that the optical absorption is sensitive to the geometric parameters such as diameter [D], length [L], and filling ratio [D/P], and more efficient light absorption can be obtained in GaAs NWAs than in thin films with the same thickness due to the combined effects of intrinsic antireflection and efficient excitation of resonant modes. Optimized geometric parameters are obtained as follows: D = 180 nm, L = 2 μm, and D/P = 0.5. Meanwhile, the simulation on the absorption of GaAs NWAs for oblique incidence has also been carried out. The underlying physics is discussed in this work.PACS: 81.07.Gf nanowires; 81.05.Ea III-V semiconductors; 88.40.hj efficiency and performance of solar cells; 73.50.Pz photoconduction and photovoltaic effects.

  18. Computational analysis of vertical axis wind turbine arrays

    NASA Astrophysics Data System (ADS)

    Bremseth, J.; Duraisamy, K.

    2016-10-01

    Canonical problems involving single, pairs, and arrays of vertical axis wind turbines (VAWTs) are investigated numerically with the objective of understanding the underlying flow structures and their implications on energy production. Experimental studies by Dabiri (J Renew Sustain Energy 3, 2011) suggest that VAWTs demand less stringent spacing requirements than their horizontal axis counterparts and additional benefits may be obtained by optimizing the placement and rotational direction of VAWTs. The flowfield of pairs of co-/counter-rotating VAWTs shows some similarities with pairs of cylinders in terms of wake structure and vortex shedding. When multiple VAWTs are placed in a column, the extent of the wake is seen to spread further downstream, irrespective of the direction of rotation of individual turbines. However, the aerodynamic interference between turbines gives rise to regions of excess momentum between the turbines which lead to significant power augmentations. Studies of VAWTs arranged in multiple columns show that the downstream columns can actually be more efficient than the leading column, a proposition that could lead to radical improvements in wind farm productivity.

  19. Dielectric Constant of Suspensions

    NASA Astrophysics Data System (ADS)

    Mendelson, Kenneth S.; Ackmann, James J.

    1997-03-01

    We have used a finite element method to calculate the dielectric constant of a cubic array of spheres. Extensive calculations support preliminary conclusions reported previously (K. Mendelson and J. Ackmann, Bull. Am. Phys. Soc. 41), 657 (1996).. At frequencies below 100 kHz the real part of the dielectric constant (ɛ') shows oscillations as a function of the volume fraction of suspension. These oscillations disappear at low conductivities of the suspending fluid. Measurements of the dielectric constant (J. Ackmann, et al., Ann. Biomed. Eng. 24), 58 (1996). (H. Fricke and H. Curtis, J. Phys. Chem. 41), 729 (1937). are not sufficiently sensitive to show oscillations but appear to be consistent with the theoretical results.

  20. AVES: A high performance computer cluster array for the INTEGRAL satellite scientific data analysis

    NASA Astrophysics Data System (ADS)

    Federici, Memmo; Martino, Bruno Luigi; Ubertini, Pietro

    2012-07-01

    In this paper we describe a new computing system array, designed, built and now used at the Space Astrophysics and Planetary Institute (IAPS) in Rome, Italy, for the INTEGRAL Space Observatory scientific data analysis. This new system has become necessary in order to reduce the processing time of the INTEGRAL data accumulated during the more than 9 years of in-orbit operation. In order to fulfill the scientific data analysis requirements with a moderately limited investment the starting approach has been to use a `cluster' array of commercial quad-CPU computers, featuring the extremely large scientific and calibration data archive on line.

  1. An annotation infrastructure for the analysis and interpretation of Affymetrix exon array data.

    PubMed

    Okoniewski, Michał J; Yates, Tim; Dibben, Siân; Miller, Crispin J

    2007-01-01

    Affymetrix exon arrays contain probesets intended to target every known and predicted exon in the entire genome, posing significant challenges for high-throughput genome-wide data analysis. X:MAP http://xmap.picr.man.ac.uk, an annotation database, and exonmap http://www.bioconductor.org/packages/2.0/bioc/html/exonmap.html, a BioConductor/R package, are designed to support fine-grained analysis of exon array data. The system supports the application of standard statistical techniques, prior to the use of genome scale annotation to provide gene-, transcript- and exon-level summaries and visualization tools.

  2. An annotation infrastructure for the analysis and interpretation of Affymetrix exon array data

    PubMed Central

    Okoniewski, Michał J; Yates, Tim; Dibben, Siân; Miller, Crispin J

    2007-01-01

    Affymetrix exon arrays contain probesets intended to target every known and predicted exon in the entire genome, posing significant challenges for high-throughput genome-wide data analysis. X:MAP , an annotation database, and exonmap , a BioConductor/R package, are designed to support fine-grained analysis of exon array data. The system supports the application of standard statistical techniques, prior to the use of genome scale annotation to provide gene-, transcript- and exon-level summaries and visualization tools. PMID:17498294

  3. Array comparative genomic hybridization analysis of olfactory neuroblastoma.

    PubMed

    Guled, Mohamed; Myllykangas, Samuel; Frierson, Henry F; Mills, Stacey E; Knuutila, Sakari; Stelow, Edward B

    2008-06-01

    Olfactory neuroblastoma is an unusual neuroectodermal malignancy, which is thought to arise at the olfactory membrane of the sinonasal tract. Due to its rarity, little is understood regarding its molecular and cytogenetic abnormalities. The aim of the current study is to identify specific DNA copy number changes in olfactory neuroblastoma. Thirteen dissected tissue samples were analyzed using array comparative genomic hybridization. Our results show that gene copy number profiles of olfactory neuroblastoma samples are complex. The most frequent changes included gains at 7q11.22-q21.11, 9p13.3, 13q, 20p/q, and Xp/q, and losses at 2q31.1, 2q33.3, 2q37.1, 6q16.3, 6q21.33, 6q22.1, 22q11.23, 22q12.1, and Xp/q. Gains were more frequent than losses, and high-stage tumors showed more alterations than low-stage olfactory neuroblastoma. Frequent changes in high-stage tumors were gains at 13q14.2-q14.3, 13q31.1, and 20q11.21-q11.23, and loss of Xp21.1 (in 66% of cases). Gains at 5q35, 13q, and 20q, and losses at 2q31.1, 2q33.3, and 6q16-q22, were present in 50% of cases. The identified regions of gene copy number change have been implicated in a variety of tumors, especially carcinomas. In addition, our results indicate that gains in 20q and 13q may be important in the progression of this cancer, and that these regions possibly harbor genes with functional relevance in olfactory neuroblastoma.

  4. Particle distribution and dynamics in a complex fluid suspension studied by an image-analysis light-scattering technique

    NASA Astrophysics Data System (ADS)

    Algarni, Saad; Kashuri, H.; Iannacchione, Germano

    2011-03-01

    A relatively unique approach is described to analyze the scattered laser light from a complex fluid suspension for both static and dynamic behavior. Recent development of speckle analysis using CCD recorded direct imaging of the scattered coherent light has opened many new avenues for the application of static and dynamic light scattering experiments. The straightforward nature of this approach is somewhat offset by the constraints of the CCD chip size and placement to probe wide (or narrow) ranges of the wave vector. An alternative, and greatly simplified variation of this technique, is to convert the scattered light into diffuse scattering using a translucent screen placed at a desired location down beam then imaging the resulting pattern on the screen. A thru-beam stop and axis scales can be easily placed on the screen and recorded to improve the image quality and later analysis. One of many possible applications is the study of the particle (7nm diam aerosil SiO2 spheres) distribution and dynamics due to Brownian motion as well as sedimentation in a complex fluid (glycerol).

  5. Hodgkin-Huxley analysis of whole-cell outward rectifying K(+)-currents in protoplasts from tobacco cell suspension cultures.

    PubMed

    Van Duijn, B

    1993-02-01

    The voltage and time dependence of outward-rectifying K+ currents (IK,out) measured in protoplasts from tobacco cell suspension cultures in the whole-cell configuration of the patch-clamp technique are quantitatively analyzed. The voltage and time dependence was described according to the Hodgkin and Huxley model for IK,out currents in the squid giant axon, and to allow comparison, in analogy with the quantitative analysis of IK,out currents in Vicia faba guard cell protoplasts as described by Schroeder (J. Membrane Biol., 107:229-235, 1989). The IK,out from tobacco could be described by a similar model as the IK,out from guard cell protoplasts (i.e., sigmoid activation time course, activation variable raised to second power, single exponential deactivating tail currents, absence of inactivation). However, in contrast to guard cells, both the activation and deactivation time constants were strongly voltage dependent in tobacco protoplasts. The voltage dependence of the transition rates for channel opening and channel closing was slightly asymmetrical and inverse to the asymmetry found in guard cells. The data presented show that the voltage-dependent kinetic properties of the IK,out conductance of tobacco protoplasts are different from these properties in guard cell protoplasts. This analysis provides a basis for the study of IK,out conductance function and modulation.

  6. A 2-D diode array and analysis software for verification of intensity modulated radiation therapy delivery.

    PubMed

    Jursinic, Paul A; Nelms, Ben E

    2003-05-01

    An analysis is made of a two-dimensional array of diodes that can be used for measuring dose generated in a plane by a radiation beam. This measuring device is the MapCHECK Model 1175 (Sun Nuclear, Melbourne, FL). This device has 445 N-type diodes in a 22 x 22 cm2 2-D array with variable spacing. The entire array of diodes is easily calibrated to allow for measurements in absolute dose. For IMRT quality assurance, each beam is measured individually with the beam central axis oriented perpendicular to the plane of diodes. Software is available to do the analytical comparison of measurements versus dose distributions calculated by a treatment planning system. Comparison criteria of percent difference and distance-to-agreement are defined by the operator. Data are presented that show the diode array has linear response when beam fluence changes by over 300-fold, which is typical of the level of modulation in intensity modulated radiation therapy, IMRT, beams. A linear dependence is also shown for a 100-fold change in monitors units delivered. Methods for how this device can be used in the clinic for quality assurance of IMRT fields are described. Measurements of typical IMRT beams that are modulated by compensators and MLCs are presented with comparisons to treatment planning system dose calculations. A time analysis is done for typical IMRT quality assurance measurements. The setup, calibration, and analysis time for the 2-D diode array are on the order of 20 min, depending on numbers of fields. This is significantly less time than required to do similar analysis with radiographic film. The 2-D diode array is ideal for per-plan quality assurance after an IMRT system is fully commissioned.

  7. Young's modulus and SEM analysis of leg bones exposed to simulated microgravity by hind limb suspension (HLS)

    SciTech Connect

    Patel, Niravkumar D.; Mehta, Rahul; Ali, Nawab; Soulsby, Michael; Chowdhury, Parimal

    2013-04-19

    The aim of this study was to determine composition of the leg bone tissue of rats that were exposed to simulated microgravity by Hind-Limb Suspension (HLS) by tail for one week. The leg bones were cross sectioned, cleaned of soft tissues, dried and sputter coated, and then placed horizontally on the stage of a Scanning Electron Microscope (SEM) for analysis. Interaction of a 17.5 keV electron beam, incident from the vertical direction on the sample, generated images using two detectors. X-rays emitted from the sample during electron bombardment were measured with an Energy Dispersive Spectroscopy (EDS) feature of SEM using a liquid-nitrogen cooled Si(Li) detector with a resolution of 144 eV at 5.9 keV ({sub 25}Mn K{sub {alpha}} x-ray). K{sub {alpha}}- x-rays from carbon, oxygen, phosphorus and calcium formed the major peaks in the spectrum. Relative percentages of these elements were determined using a software that could also correct for ZAF factors namely Z(atomic number), A(X-ray absorption) and F(characteristic fluorescence). The x-rays from the control groups and from the experimental (HLS) groups were analyzed on well-defined parts (femur, tibia and knee) of the leg bone. The SEM analysis shows that there are definite changes in the hydroxyl or phosphate group of the main component of the bone structure, hydroxyapatite [Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}], due to hind limb suspension. In a separate experiment, entire leg bones (both from HLS and control rats) were subjected to mechanical stress by mean of a variable force. The stress vs. strain graph was fitted with linear and polynomial function, and the parameters reflecting the mechanical strength of the bone, under increasing stress, were calculated. From the slope of the linear part of the graph the Young's modulus for HLS bones were calculated and found to be 2.49 times smaller than those for control bones.

  8. Young's modulus and SEM analysis of leg bones exposed to simulated microgravity by hind limb suspension (HLS)

    NASA Astrophysics Data System (ADS)

    Patel, Niravkumar D.; Mehta, Rahul; Ali, Nawab; Soulsby, Michael; Chowdhury, Parimal

    2013-04-01

    The aim of this study was to determine composition of the leg bone tissue of rats that were exposed to simulated microgravity by Hind-Limb Suspension (HLS) by tail for one week. The leg bones were cross sectioned, cleaned of soft tissues, dried and sputter coated, and then placed horizontally on the stage of a Scanning Electron Microscope (SEM) for analysis. Interaction of a 17.5 keV electron beam, incident from the vertical direction on the sample, generated images using two detectors. X-rays emitted from the sample during electron bombardment were measured with an Energy Dispersive Spectroscopy (EDS) feature of SEM using a liquid-nitrogen cooled Si(Li) detector with a resolution of 144 eV at 5.9 keV (25Mn Kα x-ray). Kα- x-rays from carbon, oxygen, phosphorus and calcium formed the major peaks in the spectrum. Relative percentages of these elements were determined using a software that could also correct for ZAF factors namely Z(atomic number), A(X-ray absorption) and F(characteristic fluorescence). The x-rays from the control groups and from the experimental (HLS) groups were analyzed on well-defined parts (femur, tibia and knee) of the leg bone. The SEM analysis shows that there are definite changes in the hydroxyl or phosphate group of the main component of the bone structure, hydroxyapatite [Ca10(PO4)6(OH)2], due to hind limb suspension. In a separate experiment, entire leg bones (both from HLS and control rats) were subjected to mechanical stress by mean of a variable force. The stress vs. strain graph was fitted with linear and polynomial function, and the parameters reflecting the mechanical strength of the bone, under increasing stress, were calculated. From the slope of the linear part of the graph the Young's modulus for HLS bones were calculated and found to be 2.49 times smaller than those for control bones.

  9. Tissue matrix arrays for high-throughput screening and systems analysis of cell function.

    PubMed

    Beachley, Vince Z; Wolf, Matthew T; Sadtler, Kaitlyn; Manda, Srikanth S; Jacobs, Heather; Blatchley, Michael R; Bader, Joel S; Pandey, Akhilesh; Pardoll, Drew; Elisseeff, Jennifer H

    2015-12-01

    Cell and protein arrays have demonstrated remarkable utility in the high-throughput evaluation of biological responses; however, they lack the complexity of native tissue and organs. Here we spotted tissue extracellular matrix (ECM) particles as two-dimensional (2D) arrays or incorporated them with cells to generate three-dimensional (3D) cell-matrix microtissue arrays. We then investigated the responses of human stem, cancer and immune cells to tissue ECM arrays originating from 11 different tissues. We validated the 2D and 3D arrays as representative of the in vivo microenvironment by means of quantitative analysis of tissue-specific cellular responses, including matrix production, adhesion and proliferation, and morphological changes after culture. The biological outputs correlated with tissue proteomics, and network analysis identified several proteins linked to cell function. Our methodology enables broad screening of ECMs to connect tissue-specific composition with biological activity, providing a new resource for biomaterials research and further understanding of regeneration and disease mechanisms.

  10. GENE ARRAY ANALYSIS OF THE VENTRAL PROSTATE IN RATS EXPOSED TO EITHER VINCLOZOLIN OR PROCYMIDONE

    EPA Science Inventory

    GENE ARRAY ANALYSIS OF THE VENTRAL PROSTATE IN RATS EXPOSED TO EITHER VINCLOZOLIN OR PROCYMIDONE. MB Rosen, VS Wilson, JE Schmid, and LE Gray Jr. US EPA, ORD, NHEERL, RTP, NC.

    Vinclozolin (Vi) and procymidone (Pr) are antiandrogenic fungicides. While changes in gene expr...

  11. Finite-difference time-domain analysis of light propagation in cholesteric liquid crystalline droplet array

    NASA Astrophysics Data System (ADS)

    Yamamoto, Kaho; Iwai, Yosuke; Uchida, Yoshiaki; Nishiyama, Norikazu

    2016-08-01

    We numerically analyzed the light propagation in cholesteric liquid crystalline (CLC) droplet array by the finite-difference time-domain (FDTD) method. The FDTD method successfully reproduced the experimental light path observed in the complicated photonic structure of the CLC droplet array more accurately than the analysis of CLC droplets by geometric optics with Bragg condition, and this method help us understand the polarization of the propagating light waves. The FDTD method holds great promise for the design of various photonic devices composed of curved photonic materials like CLC droplets and microcapsules.

  12. Rawcopy: Improved copy number analysis with Affymetrix arrays

    PubMed Central

    Mayrhofer, Markus; Viklund, Björn; Isaksson, Anders

    2016-01-01

    Microarray data is subject to noise and systematic variation that negatively affects the resolution of copy number analysis. We describe Rawcopy, an R package for processing of Affymetrix CytoScan HD, CytoScan 750k and SNP 6.0 microarray raw intensities (CEL files). Noise characteristics of a large number of reference samples are used to estimate log ratio and B-allele frequency for total and allele-specific copy number analysis. Rawcopy achieves better signal-to-noise ratio and higher proportion of validated alterations than commonly used free and proprietary alternatives. In addition, Rawcopy visualizes each microarray sample for assessment of technical quality, patient identity and genome-wide absolute copy number states. Software and instructions are available at http://rawcopy.org. PMID:27796336

  13. MATRIX DISCRIMINANT ANALYSIS WITH APPLICATION TO COLORIMETRIC SENSOR ARRAY DATA

    PubMed Central

    Suslick, Kenneth S.

    2014-01-01

    With the rapid development of nano-technology, a “colorimetric sensor array” (CSA) which is referred to as an optical electronic nose has been developed for the identification of toxicants. Unlike traditional sensors which rely on a single chemical interaction, CSA can measure multiple chemical interactions by using chemo-responsive dyes. The color changes of the chemo-responsive dyes are recorded before and after exposure to toxicants and serve as a template for classification. The color changes are digitalized in the form of a matrix with rows representing dye effects and columns representing the spectrum of colors. Thus, matrix-classification methods are highly desirable. In this article, we develop a novel classification method, matrix discriminant analysis (MDA), which is a generalization of linear discriminant analysis (LDA) for the data in matrix form. By incorporating the intrinsic matrix-structure of the data in discriminant analysis, the proposed method can improve CSA’s sensitivity and more importantly, specificity. A penalized MDA method, PMDA, is also introduced to further incorporate sparsity structure in discriminant function. Numerical studies suggest that the proposed MDA and PMDA methods outperform LDA and other competing discriminant methods for matrix predictors. The asymptotic consistency of MDA is also established. R code and data are available online as supplementary material. PMID:26783371

  14. An analysis of three new infrasound arrays around Kīlauea Volcano

    USGS Publications Warehouse

    Thelen, Weston A.; Cooper, Jennifer

    2015-01-01

    A network of three new infrasound station arrays was installed around Kīlauea Volcano between July 2012 and September 2012, and a preliminary analysis of open-vent monitoring has been completed by Hawaiian Volcano Observatory (HVO). Infrasound is an emerging monitoring method in volcanology that detects perturbations in atmospheric pressure at frequencies below 20 Hz, which can result from volcanic events that are not always observed optically or thermally. Each array has the capability to detect various infrasound events as small as 0.05 Pa as measured at the array site. The infrasound monitoring network capabilities are demonstrated through case studies of rockfalls, pit collapses, and rise-fall cycles at Halema'uma'u Crater and Pu'u 'Ōʻō.

  15. Analysis of the noise correlation in MRI coil arrays loaded with metamaterial magnetoinductive lenses.

    PubMed

    Algarin, Jose M; Breuer, Felix; Behr, Volker C; Freire, Manuel J

    2015-05-01

    A numerical method is shown for calculating the noise correlation coefficient in arrays of magnetic resonance imaging (MRI) coils loaded with capacitively-loaded ring metamaterial lenses, and in the presence of a conducting half-space resembling a sample. This numerical method is validated by comparison with experimental results obtained in two different experimental procedures for double check: noise resistance measurements with a network analyzer and noise correlation measurements in an MRI system. It is found that, for practical array configurations such as overlapping coils or capacitively-decoupled coils, the noise correlation coefficient turns negative for coils loaded with metamaterial lenses. In particular, the analysis is carried out with metamaterial structures known as magnetoinductive lenses, which have been demonstrated in previous works to improve the signal-to-noise ratio of MRI coils. Results are also shown to demonstrate that negative noise correlations have as an effect the improvement of the g-factor in coil arrays for parallel MRI.

  16. Discrimination of honeys using colorimetric sensor arrays, sensory analysis and gas chromatography techniques.

    PubMed

    Tahir, Haroon Elrasheid; Xiaobo, Zou; Xiaowei, Huang; Jiyong, Shi; Mariod, Abdalbasit Adam

    2016-09-01

    Aroma profiles of six honey varieties of different botanical origins were investigated using colorimetric sensor array, gas chromatography-mass spectrometry (GC-MS) and descriptive sensory analysis. Fifty-eight aroma compounds were identified, including 2 norisoprenoids, 5 hydrocarbons, 4 terpenes, 6 phenols, 7 ketones, 9 acids, 12 aldehydes and 13 alcohols. Twenty abundant or active compounds were chosen as key compounds to characterize honey aroma. Discrimination of the honeys was subsequently implemented using multivariate analysis, including hierarchical clustering analysis (HCA) and principal component analysis (PCA). Honeys of the same botanical origin were grouped together in the PCA score plot and HCA dendrogram. SPME-GC/MS and colorimetric sensor array were able to discriminate the honeys effectively with the advantages of being rapid, simple and low-cost. Moreover, partial least squares regression (PLSR) was applied to indicate the relationship between sensory descriptors and aroma compounds.

  17. Potential of minicomputer/array-processor system for nonlinear finite-element analysis

    NASA Technical Reports Server (NTRS)

    Strohkorb, G. A.; Noor, A. K.

    1983-01-01

    The potential of using a minicomputer/array-processor system for the efficient solution of large-scale, nonlinear, finite-element problems is studied. A Prime 750 is used as the host computer, and a software simulator residing on the Prime is employed to assess the performance of the Floating Point Systems AP-120B array processor. Major hardware characteristics of the system such as virtual memory and parallel and pipeline processing are reviewed, and the interplay between various hardware components is examined. Effective use of the minicomputer/array-processor system for nonlinear analysis requires the following: (1) proper selection of the computational procedure and the capability to vectorize the numerical algorithms; (2) reduction of input-output operations; and (3) overlapping host and array-processor operations. A detailed discussion is given of techniques to accomplish each of these tasks. Two benchmark problems with 1715 and 3230 degrees of freedom, respectively, are selected to measure the anticipated gain in speed obtained by using the proposed algorithms on the array processor.

  18. Efficient Analysis of Systems Biology Markup Language Models of Cellular Populations Using Arrays.

    PubMed

    Watanabe, Leandro; Myers, Chris J

    2016-08-19

    The Systems Biology Markup Language (SBML) has been widely used for modeling biological systems. Although SBML has been successful in representing a wide variety of biochemical models, the core standard lacks the structure for representing large complex regular systems in a standard way, such as whole-cell and cellular population models. These models require a large number of variables to represent certain aspects of these types of models, such as the chromosome in the whole-cell model and the many identical cell models in a cellular population. While SBML core is not designed to handle these types of models efficiently, the proposed SBML arrays package can represent such regular structures more easily. However, in order to take full advantage of the package, analysis needs to be aware of the arrays structure. When expanding the array constructs within a model, some of the advantages of using arrays are lost. This paper describes a more efficient way to simulate arrayed models. To illustrate the proposed method, this paper uses a population of repressilator and genetic toggle switch circuits as examples. Results show that there are memory benefits using this approach with a modest cost in runtime.

  19. An integrated analysis-synthesis array system for spatial sound fields.

    PubMed

    Bai, Mingsian R; Hua, Yi-Hsin; Kuo, Chia-Hao; Hsieh, Yu-Hao

    2015-03-01

    An integrated recording and reproduction array system for spatial audio is presented within a generic framework akin to the analysis-synthesis filterbanks in discrete time signal processing. In the analysis stage, a microphone array "encodes" the sound field by using the plane-wave decomposition. Direction of arrival of plane-wave components that comprise the sound field of interest are estimated by multiple signal classification. Next, the source signals are extracted by using a deconvolution procedure. In the synthesis stage, a loudspeaker array "decodes" the sound field by reconstructing the plane-wave components obtained in the analysis stage. This synthesis stage is carried out by pressure matching in the interior domain of the loudspeaker array. The deconvolution problem is solved by truncated singular value decomposition or convex optimization algorithms. For high-frequency reproduction that suffers from the spatial aliasing problem, vector panning is utilized. Listening tests are undertaken to evaluate the deconvolution method, vector panning, and a hybrid approach that combines both methods to cover frequency ranges below and above the spatial aliasing frequency. Localization and timbral attributes are considered in the subjective evaluation. The results show that the hybrid approach performs the best in overall preference. In addition, there is a trade-off between reproduction performance and the external radiation.

  20. Clearance Analysis of Node 3 Aft CBM to the Stowed FGB Solar Array

    NASA Technical Reports Server (NTRS)

    Liddle, Donn

    2014-01-01

    In early 2011, the ISS Vehicle Configuration Office began considering the relocation of the Permanent Multipurpose Module (PMM) to the aft facing Common Berthing Mechanism (CBM) on Node 3 to open a berthing location for visiting vehicles on the Node 1 nadir CBM. In this position, computer-aided design (CAD) models indicated that the aft end of the PMM would be only a few inches from the stowed Functional Cargo Block (FGB) port solar array. To validate the CAD model clearance analysis, in the late summer of 2011 the Image Science and Analysis Group (ISAG) was asked to determine the true geometric relationship between the on-orbit aft facing Node 3 CBM and the FGB port solar array. The desired measurements could be computed easily by photogrammetric analysis if current imagery of the ISS hardware were obtained. Beginning in the fall of 2011, ISAG used the Dynamic Onboard Ubiquitous Graphics (DOUG) program to design a way to acquire imagery of the aft face of Node 3, the aft end-cone of Node 1, the port side of pressurized mating adapter 1 (PMA1), and the port side of the FGB out to the tip of the port solar array using cameras on the Space Station Remote Manipulator System (SSRMS). This was complicated by the need to thread the SSRMS under the truss, past Node 3 and the Cupola, and into the space between the aft side of Node 3 and the FGB solar array to acquire more than 100 images from multiple positions. To minimize the number of SSRMS movements, the Special Purpose Dexterous Manipulator (SPDM) would be attached to the SSRMS. This would make it possible to park the SPDM in one position and acquire multiple images by changing the viewing orientation of the SPDM body cameras using the pan/tilt units on which the cameras are mounted. Using this implementation concept, ISAG identified four SSRMS/SPDM positions from which all of the needed imagery could be acquired. Based on a photogrammetric simulation, it was estimated that the location of the FGB solar array could be

  1. Integral Equation Formulation for the Analysis of Open-Ended Rectangular Waveguide Arrays on Cylindrical Surfaces

    NASA Astrophysics Data System (ADS)

    Gerini, G.; Visser, H. J.

    In this paper we present an efficient theoretical formulation for a full-wave analysis of phased arrays conformal to cylindrical structures. The theory is based on an integral equation formulation and the Unit Cell Approach. Thanks to its generality and efficiency, this method represents a good starting point for the development of accurate CAD tools for the analysis of integrated cylindrical structures including radome, coaxial excitations and tuning elements in waveguide.

  2. A laboratory study on sediment resuspension within arrays of rigid cylinders

    NASA Astrophysics Data System (ADS)

    Tinoco, Rafael O.; Coco, Giovanni

    2016-06-01

    We present results from laboratory experiments on flow through submerged arrays of rigid cylinders embedded in a sandy bed. Using rigid, cylindrical elements to mimic vegetation and benthos, we account for only the physical effects resulting from their presence, eliminating biological factors, such as biofilms and root systems. In line with previous findings, rigid arrays modify the flow mean and turbulent velocity statistics. However, even if the flow speed is significantly damped within dense arrays, the amount of sediment that gets lifted into suspension increases as the density of the array increases due to array- and cylinder-scale turbulence. We present a first attempt to provide predictive relationships of suspended sediment concentration using an alternative approach for the Shields parameter with an empirical coefficient to account for turbulence generated by submerged arrays of rigid cylinders. A similar analysis, using a ratio of populated to non-populated Shields parameter, is conducted to predict resuspension as a function of array density.

  3. Analysis of boutique arrays: a universal method for the selection of the optimal data normalization procedure.

    PubMed

    Uszczyńska, Barbara; Zyprych-Walczak, Joanna; Handschuh, Luiza; Szabelska, Alicja; Kaźmierczak, Maciej; Woronowicz, Wiesława; Kozłowski, Piotr; Sikorski, Michał M; Komarnicki, Mieczysław; Siatkowski, Idzi; Figlerowicz, Marek

    2013-09-01

    DNA microarrays, which are among the most popular genomic tools, are widely applied in biology and medicine. Boutique arrays, which are small, spotted, dedicated microarrays, constitute an inexpensive alternative to whole-genome screening methods. The data extracted from each microarray-based experiment must be transformed and processed prior to further analysis to eliminate any technical bias. The normalization of the data is the most crucial step of microarray data pre-processing and this process must be carefully considered as it has a profound effect on the results of the analysis. Several normalization algorithms have been developed and implemented in data analysis software packages. However, most of these methods were designed for whole-genome analysis. In this study, we tested 13 normalization strategies (ten for double-channel data and three for single-channel data) available on R Bioconductor and compared their effectiveness in the normalization of four boutique array datasets. The results revealed that boutique arrays can be successfully normalized using standard methods, but not every method is suitable for each dataset. We also suggest a universal seven-step workflow that can be applied for the selection of the optimal normalization procedure for any boutique array dataset. The described workflow enables the evaluation of the investigated normalization methods based on the bias and variance values for the control probes, a differential expression analysis and a receiver operating characteristic curve analysis. The analysis of each component results in a separate ranking of the normalization methods. A combination of the ranks obtained from all the normalization procedures facilitates the selection of the most appropriate normalization method for the studied dataset and determines which methods can be used interchangeably.

  4. Zarya Energy Balance Analysis: The Effect of Spacecraft Shadowing on Solar Array Performance

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Kolosov, Vladimir

    1999-01-01

    The first element of the International Space Station (ISS). Zarya, was funded by NASA and built by the Russian aerospace company Khrunichev State Research and Production Space Center (KhSC). NASA Glenn Research Center (GRC) and KhSC collaborated in performing analytical predictions of the on-orbit electrical performance of Zarya's solar arrays. GRC assessed the pointing characteristics of and shadow patterns on Zarya's solar arrays to determine the average solar energy incident on the arrays. KHSC used the incident energy results to determine Zarya's electrical power generation capability and orbit-average power balance. The power balance analysis was performed over a range of solar beta angles and vehicle operational conditions. This analysis enabled identification of problems that could impact the power balance for specific flights during ISS assembly and was also used as the primary means of verifying that Zarya complied with electrical power requirements. Analytical results are presented for select stages in the ISS assembly sequence along with a discussion of the impact of shadowing on the electrical performance of Zarya's solar arrays.

  5. Spherical harmonic analysis of the sound radiation from omnidirectional loudspeaker arrays

    NASA Astrophysics Data System (ADS)

    Pasqual, A. M.

    2014-09-01

    Omnidirectional sound sources are widely used in room acoustics. These devices are made up of loudspeakers mounted on a spherical or polyhedral cabinet, where the dodecahedral shape prevails. Although such electroacoustic sources have been made readily available to acousticians by many manufacturers, an in-depth investigation of their vibroacoustic behavior has not been provided yet. In order to fulfill this lack, this paper presents a theoretical study of the sound radiation from omnidirectional loudspeaker arrays, which is carried out by using a mathematical model based on the spherical harmonic analysis. Eight different loudspeaker arrangements on the sphere are considered: the well-known five Platonic solid layouts and three extremal system layouts. The latter possess useful properties for spherical loudspeaker arrays used as directivity controlled sound sources, so that these layouts are included here in order to investigate whether or not they could be of interest as omnidirectional sources as well. It is shown through a comparative analysis that the dodecahedral array leads to the lowest error in producing an omnidirectional sound field and to the highest acoustic power, which corroborates the prevalence of such a layout. In addition, if a source with less than 12 loudspeakers is required, it is shown that tetrahedra or hexahedra can be used alternatively, whereas the extremal system layouts are not interesting choices for omnidirectional loudspeaker arrays.

  6. [Analysis of oxygen transfer in bioreactors for fungus broths. 2. Suspensions of P. chrysogenum mycelial associations].

    PubMed

    Caşcaval, D; Galaction, Anca-Irina; Cămăruţ, Stefănica

    2009-01-01

    Unlike the P. shermanii and S. cerevisiae cultures, the study on the distribution of oxygen transfer in stirred bioreactor for P. chrysogenum pellets broths indicated that this process is controlled mainly by the deposition tendency of the biomass. Similar to the previously studied systems, the analysis of k(1)a distribution indicated its heterogeneity on the bioreactor height, the oxygen transfer rate increasing from position 1 to 4. Contrary to the bacterial and yeasts cultures, the intensification of aeration promoted the initial reduction of k(1)a, which reached a minimum level, followed by its increase, due to the flooding phenomenon.

  7. Sensitivity- and effort-gain analysis: multilead ECG electrode array selection for activation time imaging.

    PubMed

    Hintermüller, Christoph; Seger, Michael; Pfeifer, Bernhard; Fischer, Gerald; Modre, Robert; Tilg, Bernhard

    2006-10-01

    Methods for noninvasive imaging of electric function of the heart might become clinical standard procedure the next years. Thus, the overall procedure has to meet clinical requirements as an easy and fast application. In this paper, we propose a new electrode array which improves the resolution of methods for activation time imaging considering clinical constraints such as easy to apply and compatibility with routine leads. For identifying the body-surface regions where the body surface potential (BSP) is most sensitive to changes in transmembrane potential (TMP), a virtual array method was used to compute local linear dependency (LLD) maps. The virtual array method computes a measure for the LLD in every point on the body surface. The most suitable number and position of the electrodes within the sensitive body surface regions was selected by constructing effort gain (EG) plots. Such a plot depicts the relative attainable rank of the leadfield matrix in relation to the increase in number of electrodes required to build the electrode array. The attainable rank itself was computed by a detector criterion. Such a criterion estimates the maximum number of source space eigenvectors not covered by noise when being mapped to the electrode space by the leadfield matrix and recorded by a detector. From the sensitivity maps, we found that the BSP is most sensitive to changes in TMP on the upper left frontal and dorsal body surface. These sensitive regions are covered best by an electrode array consisting of two L-shaped parts of approximately 30 cm x 30 cm and approximately 20 cm x 20 cm. The EG analysis revealed that the array meeting clinical requirements best and improving the resolution of activation time imaging consists of 125 electrodes with a regular horizontal and vertical spacing of 2-3 cm.

  8. EDITORIAL: Colloidal suspensions Colloidal suspensions

    NASA Astrophysics Data System (ADS)

    Petukhov, Andrei; Kegel, Willem; van Duijneveldt, Jeroen

    2011-05-01

    Special issue in honour of Henk Lekkerkerker's 65th birthday Professor Henk N W Lekkerkerker is a world-leading authority in the field of experimental and theoretical soft condensed matter. On the occasion of his 65th birthday in the summer of 2011, this special issue celebrates his many contributions to science. Henk Lekkerkerker obtained his undergraduate degree in chemistry at the University of Utrecht (1968) and moved to Calgary where he received his PhD in 1971. He moved to Brussels as a NATO fellow at the Université Libre de Bruxelles and was appointed to an assistant professorship (1974), an associate professorship (1977) and a full professorship (1980) in physical chemistry at the Vrije Universiteit Brussel. In 1985 he returned to The Netherlands to take up a professorship at the Van 't Hoff Laboratory, where he has been ever since. He has received a series of awards during his career, including the Onsager Medal (1999) of the University of Trondheim, the Bakhuys Roozeboom Gold Medal (2003) of the Royal Dutch Academy of Arts and Sciences (KNAW), the ECIS-Rhodia European Colloid and Interface Prize (2003), and the Liquid Matter Prize of the European Physical Society (2008). He was elected a member of KNAW in 1996, was awarded an Academy Chair position in 2005, and has held several visiting lectureships. Henk's work focuses on phase transitions in soft condensed matter, and he has made seminal contributions to both the theoretical and experimental aspects of this field. Here we highlight three major themes running through his work, and a few selected publications. So-called depletion interactions may lead to phase separation in colloid-polymer mixtures, and Henk realised that the partitioning of polymer needs to be taken into account to describe the phase behaviour correctly [1]. Colloidal suspensions can be used as model fluids, with the time- and length-scales involved leading to novel opportunities, notably the direct observation of capillary waves at a

  9. Array analysis methods for detection, classification and location of seismic sources: a first evaluation for aftershock analysis using dense temporary post-seismic array network

    NASA Astrophysics Data System (ADS)

    Poiata, N.; Satriano, C.; Vilotte, J.; Bernard, P.

    2012-12-01

    Detection, separation, classification and location of distributed non stationary seismic sources in broadband noisy environment is an important problem in seismology, in particular for monitoring the high-level post-seismic activity following large subduction earthquakes, like the off-shore Maule (Mw 8.8, 2010) earthquake in Central Chile. Multiple seismic arrays, and local antenna, distributed over a region allow exploiting frequency selective coherence of the signals that arrive at widely-separated array stations, leading to improved detection, convolution blind source separation, and location of distributed non stationary sources. We present here first results on the investigation of time-frequency adaptive array analysis techniques for detection and location of broadband distributed seismic events recorded by the dense temporary seismic network (International Maule Aftershock Deployment, IMAD) installed for monitoring the high-level seismic activity following the 27 February 2010 Maule earthquake (Mw 8.8). This seismic network is characterized by a large aperture, with variable inter-station distances, corroborated with a high level of distributed near and far field seismic source activity and noise. For this study, we first extract from the post-seismic network a number of seismic arrays distributed over the region covered by this network. A first aspect is devoted to passive distributed seismic sources detection, classification and separation. We investigate a number of narrow and wide band signal analysis methods both in time and time-frequency domains for energy arrival detection and tracking, including time adaptive higher order statistics, e.g. like kurtosis, and multiband band-pass filtering, together with adaptive time-frequency transformation and extraction techniques. We demonstrate that these techniques provide superior resolution and robustness than classical STA/LTA techniques in particular in the case of distributed sources with potential signal

  10. Integrated dynamic analysis simulation of space stations with controllable solar array

    NASA Technical Reports Server (NTRS)

    Heinrichs, J. A.; Fee, J. J.

    1972-01-01

    A methodology is formulated and presented for the integrated structural dynamic analysis of space stations with controllable solar arrays and non-controllable appendages. The structural system flexibility characteristics are considered in the dynamic analysis by a synthesis technique whereby free-free space station modal coordinates and cantilever appendage coordinates are inertially coupled. A digital simulation of this analysis method is described and verified by comparison of interaction load solutions with other methods of solution. Motion equations are simulated for both the zero gravity and artificial gravity (spinning) orbital conditions. Closed loop controlling dynamics for both orientation control of the arrays and attitude control of the space station are provided in the simulation by various generic types of controlling systems. The capability of the simulation as a design tool is demonstrated by utilizing typical space station and solar array structural representations and a specific structural perturbing force. Response and interaction load solutions are presented for this structural configuration and indicate the importance of using an integrated type analysis for the predictions of structural interactions.

  11. Heat transfer analysis on peristaltically induced motion of particle-fluid suspension with variable viscosity: Clot blood model.

    PubMed

    Bhatti, M M; Zeeshan, A; Ellahi, R

    2016-12-01

    In this article, heat transfer analysis on clot blood model of the particle-fluid suspension through a non-uniform annulus has been investigated. The blood propagating along the whole length of the annulus was induced by peristaltic motion. The effects of variable viscosity and slip condition are also taken into account. The governing flow problem is modeled using lubrication approach by taking the assumption of long wavelength and creeping flow regime. The resulting equation for fluid phase and particle phase is solved analytically and closed form solutions are obtained. The physical impact of all the emerging parameters is discussed mathematically and graphically. Particularly, we considered the effects of particle volume fraction, slip parameter, the maximum height of clot, viscosity parameter, average volume flow rate, Prandtl number, Eckert number and fluid parameter on temperature profile, pressure rise and friction forces for outer and inner tube. Numerical computations have been used to determine the behavior of pressure rise and friction along the whole length of the annulus. The present study is also presented for an endoscope as a special case of our study. It is observed that greater influence of clot tends to rise the pressure rise significantly. It is also found that temperature profile increases due to the enhancement in Prandtl number, Eckert number, and fluid parameter. The present study reveals that friction forces for outer tube have higher magnitude as compared to the friction forces for an inner tube. In fact, the results for present study can also be reduced to the Newtonian fluid by taking ζ → ∞.

  12. [COMPARATIVE CYTOGENETIC ANALYSIS OF MONOLAYER AND SUSPENSION CHINESE HAMSTER OVARY CELL LINES CHO(dhfr-)].

    PubMed

    Stefanova, V N; Yartseva, N M; Petrov, A V

    2015-01-01

    The karyotypes of CHO(dhfr-) and CHO(dhfr-)/susp Chinese hamster ovary cell lines were investigated with the use of GTG-staining. Modal chromosome set consists of 20 and 18 chromosomes respectively. The karyotypes of both cell lines were stable with constant ratio of normal chromosomes and chromosomes with structural rearrangements. Monosomy for chromosomes 1, 2, 4, 5, 8 was observed in both cell lines and for chromosome 9 in CHO(dhfr-)/susp cell line. The differences between CHO(dhfr-) cell lines studied by us consists of inclusion of part of chromosome 7 in der(6)t(1;6), rearrangement of del(5) and monosomy of chromosome 9. It was shown that in karyotypes of all CHO cell lines studied up today there are 5 common structurally chromosome rearrangements: del(2), inv(3), add(6), del(9) and mar1. In both CHO(dhfr-) cell lines investigated by us three unique chromosome rearrangements: del(1), der(6)t(1,6) and mar3 were revealed. Necessity of simultaneous GTG and FISH analysis of chromosomes rearrangements in the CHO cell lines under study is discussed.

  13. Identification of the mechanism underlying a human chimera by SNP array analysis.

    PubMed

    Shin, So Youn; Yoo, Han-Wook; Lee, Beom Hee; Kim, Kun Suk; Seo, Eul-Ju

    2012-09-01

    Human chimerism resulting from the fusion of two different zygotes is a rare phenomenon. Two mechanisms of chimerism have been hypothesized: dispermic fertilization of an oocyte and its second polar body and dispermic fertilization of two identical gametes from parthenogenetic activation, and these can be identified and discriminated using DNA polymorphism. In the present study we describe a patient with chimerism presenting as a true hermaphrodite and applied single nucleotide polymorphism array analysis to demonstrate dispermic fertilization of two identical gametes from parthenogenetic activation as the underlying mechanism at the whole chromosome level. We suggest that application of genotyping array analysis to the diagnostic process in patients with disorders of sex development will help identify more human chimera patients and increase our understanding of the underlying mechanisms.

  14. ArrayNinja: An Open Source Platform for Unified Planning and Analysis of Microarray Experiments

    PubMed Central

    Dickson, B.M.; Cornett, E.M.; Ramjan, Z.; Rothbart, S.B.

    2017-01-01

    Microarray-based proteomic platforms have emerged as valuable tools for studying various aspects of protein function, particularly in the field of chromatin biochemistry. Microarray technology itself is largely unrestricted in regard to printable material and platform design, and efficient multidimensional optimization of assay parameters requires fluidity in the design and analysis of custom print layouts. This motivates the need for streamlined software infrastructure that facilitates the combined planning and analysis of custom microarray experiments. To this end, we have developed ArrayNinja as a portable, open source, and interactive application that unifies the planning and visualization of microarray experiments and provides maximum flexibility to end users. Array experiments can be planned, stored to a private database, and merged with the imaged results for a level of data interaction and centralization that is not currently attainable with available microarray informatics tools. PMID:27423857

  15. Breath analysis system for early detection of lung diseases based on multi-sensor array

    NASA Astrophysics Data System (ADS)

    Jeon, Jin-Young; Yu, Joon-Boo; Shin, Jeong-Suk; Byun, Hyung-Gi; Lim, Jeong-Ok

    2013-05-01

    Expiratory breath contains various VOCs(Volatile Organic Compounds) produced from the human. When a certain disease exists, the exhalation has specific VOCs which may be generated from diseases. Many researchers have been actively working to find different types of biomarkers which are characteristic for particular diseases. Research regarding the identification of specific diseases from exhalation is still in progress. The aim of this research is to implement early detection of lung disease such as lung cancer and COPD(Chronic Obstructive Pulmonary Disease), which was nominated on the 6th of domestic death rate in 2010, based on multi-sensor array system. The system has been used to acquire sampled expiratory gases data and PCA(Principle Component Analysis) technique was applied to analyze signals from multi-sensor array. Throughout the experimental trials, a clearly distinguishable difference between lung disease patients and healthy controls was found from the measurement and analysis of their respective expiratory gases.

  16. Large Angle Magnetic Suspension Test Fixture

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P.; Huang, Jen-Kuang

    1997-01-01

    Progress in the areas of eddy current computations, modelling and analysis, design optimization methods, wind tunnel Magnetic Suspension and Balance Systems (MSBS), payload pointing and vibration isolation systems, and system identification is reported. Research accomplishments facilitated the demonstration of several new developments in the field of magnetic suspension technology.

  17. Urinary incontinence - retropubic suspension

    MedlinePlus

    ... Marchetti-Krantz (MMK) procedure; Laparoscopic retropubic colposuspension; Needle suspension; Burch colposuspension ... bladder. There are two ways to do retropubic suspension: open surgery or laparoscopic surgery. Either way, surgery ...

  18. Stability Analysis of Roughness Array Wake in a High-Speed Boundary Layer

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan; Li, Fei; Edwards, Jack

    2009-01-01

    Computations are performed to examine the effects of both an isolated and spanwise periodic array of trip elements on a high-speed laminar boundary layer, so as to identify the potential physical mechanisms underlying an earlier transition to turbulence as a result of the trip(s). In the context of a 0.333 scale model of the Hyper-X forebody configuration, the time accurate solution for an array of ramp shaped trips asymptotes to a stationary field at large times, indicating the likely absence of a strong absolute instability in the mildly separated flow due to the trips. A prominent feature of the wake flow behind the trip array corresponds to streamwise streaks that are further amplified in passing through the compression corner. Stability analysis of the streaks using a spatial, 2D eigenvalue approach reveals the potential for a strong convective instability that might explain the earlier onset of turbulence within the array wake. The dominant modes of streak instability are primarily sustained by the spanwise gradients associated with the streaks and lead to integrated logarithmic amplification factors (N factors) approaching 7 over the first ramp of the scaled Hyper-X forebody, and substantially higher over the second ramp. Additional computations are presented to shed further light on the effects of both trip geometry and the presence of a compression corner on the evolution of the streaks.

  19. HST Solar array impact survey: revised damage laws and residue analysis

    NASA Astrophysics Data System (ADS)

    Drolshagen, G.; Carey, W. C.; McDonnell, J. A. M.; Stevenson, T. J.; Mandeville, J. C.; Berthoud, L.

    1997-05-01

    This report presents results of the analysis of impact features on the retrieved Hubble Space Telescope (HST) solar array and compares them to similar data from EURECA. The post-flight meteroid/debris investigation programmes included optical surveys of all outer surfaces, impact residue analyses and hypervelocity calibration tests on MLI and solar array samples. Observed crater sizes range from about 2 μm to 6-7 mm. On the HST solar array impact fluxes at the same crater pit diameter are higher than for EURECA for sizes exceeding about 200 μm while they are comparable for smaller sizes. Impact fluxes on EURECA and HST do both exceed the 6 face averaged fluxes on LDEF. The residue analyses which were performed for EURECA MLI and HST solar array samples proved very difficult due to the complexity of the targets and they produced somewhat inconclusive results. Some results of hypervelocity impact calibration tests are presented. A comparison between the measured impact data and the predictions of present flux models is given.

  20. Analysis and comparison of two two-dimensional Halbach permanent magnet arrays for magnetically levitated planar motor

    NASA Astrophysics Data System (ADS)

    Zhang, Lu; Kou, Baoquan; Xing, Feng; Zhang, He

    2014-05-01

    A novel 2-D Halbach permanent magnet array which can be used in magnetically levitated planar motor is proposed in this paper. The air-gap flux density distribution of the novel 2-D Halbach permanent magnet array is solved by the scalar magnetic potential equation. In order to compare with the well-known Halbach magnet array that was used by Jansen et al. [IEEE Trans. Ind. Appl. 44(4), 1108 (2008)], harmonic analysis of the x- and z- component of the air-gap flux density are carried out by Fourier decomposition. Comparison of Bx and Bz between the two 2-D Halbach magnet arrays are made. And it is verified that the performance of the new Halbach magnet array is superior to the existing Halbach magnet arrays, its higher magnetic flux density and lower high-order harmonics will help to improve the performance of the magnetically levitated planar motor.

  1. Colorimetric sensor arrays for the analysis of beers: a feasibility study.

    PubMed

    Zhang, Chen; Bailey, Daniel P; Suslick, Kenneth S

    2006-07-12

    Eighteen commercial beers have been analyzed in both liquid and gas phases using colorimetric sensor arrays made from selected chemically responsive dyes printed on a hydrophobic membrane. Digital imaging of the dye array before and after exposure to the complex analytes in either the liquid phase or the head-gas provides a color change profile as a unique fingerprint for the specific analyte. The digital data libraries generated were analyzed using statistical and chemometric methods, including principal component analysis (PCA) and hierarchical clustering analysis (HCA). In either liquid- or gas-phase experiments, facile identification of specific beers was achieved using comparison of the color change profiles; using HCA statistical analysis the error rate of identification was <3%. Differentiation between even very similar beers proved to be straightforward. In addition, differentiation of pristine beer from the effects of watering or decarbonation proved to be possible. These results suggest that colorimetric sensor arrays may prove to be useful for quality assurance/quality control applications of beers and perhaps other beverages.

  2. Beyond Behavior: Multilevel Analysis of the Influence of Sociodemographics and School Characteristics on Students' Risk of Suspension

    ERIC Educational Resources Information Center

    Sullivan, Amanda L.; Klingbeil, David A.; Van Norman, Ethan R.

    2013-01-01

    Minority disproportionality in school discipline outcomes continues to trouble practitioners and scholars. The purpose of this study was to examine the influence of sociodemographic characteristics and indicators of school policy enactment (e.g., retention rates, special education identification) on students' risk of suspension. The sample…

  3. SNP Arrays

    PubMed Central

    Louhelainen, Jari

    2016-01-01

    The papers published in this Special Issue “SNP arrays” (Single Nucleotide Polymorphism Arrays) focus on several perspectives associated with arrays of this type. The range of papers vary from a case report to reviews, thereby targeting wider audiences working in this field. The research focus of SNP arrays is often human cancers but this Issue expands that focus to include areas such as rare conditions, animal breeding and bioinformatics tools. Given the limited scope, the spectrum of papers is nothing short of remarkable and even from a technical point of view these papers will contribute to the field at a general level. Three of the papers published in this Special Issue focus on the use of various SNP array approaches in the analysis of three different cancer types. Two of the papers concentrate on two very different rare conditions, applying the SNP arrays slightly differently. Finally, two other papers evaluate the use of the SNP arrays in the context of genetic analysis of livestock. The findings reported in these papers help to close gaps in the current literature and also to give guidelines for future applications of SNP arrays. PMID:27792140

  4. Analysis and design of coupled-oscillator arrays for microwave systems

    NASA Astrophysics Data System (ADS)

    Moussounda, Renaud

    The concept of synchronized nonlinear coupled oscillators is applied to microwave and antenna engineering for the analysis and design of wireless communication and sensing systems operating at the microwave and/or millimeter (mm)-wave frequencies. The significance of such approach is justified from the potential gain in efficiency, weight, cost and functionality although technical challenges stand in the way. Unlike typical phased array systems, which are currently used to construct such systems, coupled-oscillator systems present additional challenges that mainly arise from maintaining stability and synchronization as the the coupled nonlinear system is operated. Linear systems do not present such stability issues and are consequently faster since they do not rely on any gradual synchronization mechanism in order to function. However, at significantly higher frequencies in the quasi-optical domain, coupled-oscillator systems can make up for the speed difference and present significant efficiency advantages over typical phased array architectures. In addition, coupled nonlinear systems possess inherent analog properties that can be used for a multitude of functions. This dissertation advances the topic of coupled-oscillator arrays by 1) developing an alternative set of techniques for designing the oscillating unit cells called active integrated antennas (AIAs) at microwave or mm-wave frequencies, 2) developing a more accurate description of the dynamics of the array, 3) developing and implementing a new topology for a coupling network that is able to extend stability, 4) implementing a fully non-reciprocally coupled array able to produce large scan angle without loss of stability, 5) proposing an architecture based on a single phase-locked loop (PLL) and containing a self-calibration mechanism, and finally 6) implementing a phase-boosting mechanism using simple circuits to amplify the phase difference between adjacent radiating antennas in order to increase

  5. Analysis of Waves in the Near-Field of Wave Energy Converter Arrays through Stereo Video

    NASA Astrophysics Data System (ADS)

    Black, C.; Haller, M. C.

    2013-12-01

    Oregon State University conducted a series of laboratory experiments to measure and quantify the near-field wave effects caused within arrays of 3 and 5 Wave Energy Converters (WEC). As the waves and WECs interact, significant scattering and radiation occurs increasing/decreasing the wave heights as well as changing the direction the wave is traveling. These effects may vary based on the number of WECs within an array and their respective locations. The findings of this analysis will assist in selecting the WEC farm location and in improving WEC design. Analyzing the near-field waves will help determine the relative importance of absorption, scattering, and radiation as a function of the incident wave conditions and device performance. The WEC mooring system design specifications may also be impacted if the wave heights in the near-field are greater than expected. It is imperative to fully understand the near-field waves before full-scale WEC farms can be installed. Columbia Power Technologies' Manta served as the test WEC prototype on a 1 to 33 scale. Twenty-three wave gages measured the wave heights in both regular and real sea conditions at locations surrounding and within the WEC arrays. While these gages give a good overall picture of the water elevation behavior, it is difficult to resolve the complicated wave field within the WEC array using point gages. Here stereo video techniques are applied to extract the 3D water surface elevations at high resolution in order to reconstruct the multi-directional wave field in the near-field of the WEC array. The video derived wave information will also be compared against the wave gage data.

  6. Multiple seismic array analysis of low frequency tremors in western Shikoku, Japan

    NASA Astrophysics Data System (ADS)

    Ueno, T.; Maeda, T.; Obara, K.; Asano, Y.; Takeda, T.

    2007-12-01

    In southwest Japan, low frequency tremors (LFTs) have been detected at deeper part of the seismogenic zone on the subducting Philippine Sea plate interface by high sensitivity seismograph network Hi-net operated by NIED. The tremor source area migrates during each episode along the strike of the subducting plate with a migration velocity of roughly 10 km/day, which was referred from source locations obtained by the envelope correlation method. In order to investigate the wave field propagation from the tremors in detail, we carried out a seismic observation campaign in western Shikoku, where the active tremor associated with the short-term slow slip event occurs with a recurrence interval of around six months. In this campaign, we deployed three seismic arrays above the belt-like LFT area with a spacing of about 20 km among arrays, during the period from February to May in 2007 because we anticipated the coming LFT episode to occur on March or April, 2007. Each array was composed of 32-channel receivers which mainly consist of vertical-component with natural frequency of 2 Hz. The receivers were placed with an average spacing of 30 m. Waveform data were recorded continuously with a sampling interval of 0.01 s. Since the active tremor episode with the short-term slow slip event occurred from 13 to 15 on March 2007 as expected, we performed frequency-wave number power spectrum analysis for each array recordings by the MUltiple SIgnal Classification (MUSIC) method in the period. At two seismic arrays, the apparent slowness were continuously low during the tremor episode. At the other array, the slowness was relatively high, and the arrival direction of the waves slightly changed with increasing time. In order to ascertain the change to be migration of the tremors, we located the sources of tremors by grid search method by using backazimuth and apparent slowness estimated at each array. We successfully located the sources of tremors, and detected the migration of the

  7. Interfacing Inorganic Nanowire Arrays and Living Cells for Cellular Function Analysis.

    PubMed

    Kwak, Minsuk; Han, Lin; Chen, Jonathan J; Fan, Rong

    2015-11-11

    Inorganic nanowires are among the most attractive functional materials, which have emerged in the past two decades. They have demonstrated applications in information technology and energy conversion, but their utility in biological or biomedical research remains relatively under-explored. Although nanowire-based sensors have been frequently reported for biomolecular detection, interfacing nanowire arrays and living mammalian cells for the direct analysis of cellular functions is a very recent endeavor. Cell-penetrating nanowires enabled effective delivery of biomolecules, electrical and optical stimulation and recording of intracellular signals over a long period of time. Non-penetrating, high-density nanowire arrays display rich interactions between the nanostructured substrate and the micro/nanoscale features of cell surfaces. Such interactions enable efficient capture of rare cells including circulating tumor cells and trafficking leukocytes from complex biospecimens. It also serves as a platform for probing cell traction force and neuronal guidance. The most recent advances in the field that exploits nanowire arrays (both penetrating and non-penetrating) to perform rapid analysis of cellular functions potentially for disease diagnosis and monitoring are reviewed.

  8. A differential array of metalated synthetic receptors for the analysis of tripeptide mixtures.

    PubMed

    Wright, Aaron T; Anslyn, Eric V; McDevitt, John T

    2005-12-14

    A novel library of resin-bound receptors within a cross-reactive differential array for the identification and discrimination of tripeptides and tripeptide mixtures is reported. Pattern recognition using principal component analysis showed complete discrimination of four similar tripeptides and three tripeptide mixtures. The library is comprised of a Cu(II)-centered core with two proximally appended tripeptide arms emanating outward. One tripeptide arm was prepared using combinatorial chemistry to generate the differential nature of the library. Thirty resin-bound receptors were randomly selected from the library and placed within a silicon microchip array that included integrated microfluidics elements, and an indicator-uptake assay was used for colorimetric signaling. The indicator Orange G yielded an accurate measure of the degree of association between receptors and analytes as determined by kinetic analysis of the indicator-uptake assays. Within this paper we detail the method used for differential sensing using a novel receptor library. This work further demonstrates the power and utility of a differential array of synthetic receptors for identification and discrimination of complex bioanalytes.

  9. Design and test analysis of a solar array root hinge drive assembly

    NASA Astrophysics Data System (ADS)

    Ding, Xilun; Li, Xin

    2014-09-01

    A root hinge drive assembly is preferred in place of the classical viscous damper in a large solar array system. It has advantages including better deployment control and higher reliability. But the traditional single degree of freedom model should be improved. A multiple degrees of freedom dynamics model is presented for the solar arrays deployment to guide the drive assembly design. The established model includes the functions of the torsion springs, the synchronization mechanism and the lock-up impact. A numerical computation method is proposed to solve the dynamics coupling problem. Then considering the drive torque requirement calculated by the proposed model, a root hinge drive assembly is developed based on the reliability engineering design methods, and dual actuators are used as a redundancy design. Pseudo-efficiency is introduced and the major factors influencing the (pseudo-) efficiency of the gear mechanism designed with high reduction ratio are studied for further test data analysis. A ground prototype deployment test is conducted to verify the capacity of the drive assembly. The test device consists of a large-area solar array system and a root hinge drive assembly. The RHDA development time is about 43 s. The theoretical drive torque is compared with the test values which are obtained according to the current data and the reduction efficiency analysis, and the results show that the presented model and the calibration methods are proper enough.

  10. Teleseismic P-wave polarization analysis at the Gräfenberg array

    NASA Astrophysics Data System (ADS)

    Cristiano, L.; Meier, T.; Krüger, F.; Keers, H.; Weidle, C.

    2016-12-01

    P-wave polarization at the Gräfenberg array (GRF) in southern Germany is analysed in terms of azimuthal deviations and deviations in the vertical polarization using 20 yr of broad-band recordings. An automated procedure for estimating P-wave polarization parameters is suggested, based on the definition of a characteristic function, which evaluates the polarization angles and their time variability as well as the amplitude, linearity and the signal-to-noise ratio of the P wave. P-wave polarization at the GRF array is shown to depend mainly on frequency and backazimuth and only slightly on epicentral distance indicating depth-dependent local anisotropy and lateral heterogeneity. A harmonic analysis is applied to the azimuthal anomalies to analyse their periodicity as a function of backazimuth. The dominant periods are 180° and 360°. At low frequencies, between 0.03 and 0.1 Hz, the observed fast directions of azimuthal anisotropy inferred from the 180° periodicity are similar across the array. The average fast direction of azimuthal anisotropy at these frequencies is N20°E with an uncertainty of about 8° and is consistent with fast directions of Pn-wave propagation. Lateral velocity gradients determined for the low-frequency band are compatible with the Moho topography of the area. A more complex pattern in the horizontal fast axis orientation beneath the GRF array is observed in the high-frequency band between 0.1 and 0.5 Hz, and is attributed to anisotropy in the upper crust. A remarkable rotation of the horizontal fast axis orientation across the suture between the geological units Moldanubicum and Saxothuringicum is observed. In contrast, the 360° periodicity at high frequencies is rather consistent across the array and may either point to lower velocities in the upper crust towards the Bohemian Massif and/or to anisotropy dipping predominantly in the NE-SW direction. Altogether, P-wave polarization analysis indicates the presence of layered lithospheric

  11. Failure mode analysis of silicon-based intracortical microelectrode arrays in non-human primates

    NASA Astrophysics Data System (ADS)

    Barrese, James C.; Rao, Naveen; Paroo, Kaivon; Triebwasser, Corey; Vargas-Irwin, Carlos; Franquemont, Lachlan; Donoghue, John P.

    2013-12-01

    Objective. Brain-computer interfaces (BCIs) using chronically implanted intracortical microelectrode arrays (MEAs) have the potential to restore lost function to people with disabilities if they work reliably for years. Current sensors fail to provide reliably useful signals over extended periods of time for reasons that are not clear. This study reports a comprehensive retrospective analysis from a large set of implants of a single type of intracortical MEA in a single species, with a common set of measures in order to evaluate failure modes. Approach. Since 1996, 78 silicon MEAs were implanted in 27 monkeys (Macaca mulatta). We used two approaches to find reasons for sensor failure. First, we classified the time course leading up to complete recording failure as acute (abrupt) or chronic (progressive). Second, we evaluated the quality of electrode recordings over time based on signal features and electrode impedance. Failure modes were divided into four categories: biological, material, mechanical, and unknown. Main results. Recording duration ranged from 0 to 2104 days (5.75 years), with a mean of 387 days and a median of 182 days (n = 78). Sixty-two arrays failed completely with a mean time to failure of 332 days (median = 133 days) while nine array experiments were electively terminated for experimental reasons (mean = 486 days). Seven remained active at the close of this study (mean = 753 days). Most failures (56%) occurred within a year of implantation, with acute mechanical failures the most common class (48%), largely because of connector issues (83%). Among grossly observable biological failures (24%), a progressive meningeal reaction that separated the array from the parenchyma was most prevalent (14.5%). In the absence of acute interruptions, electrode recordings showed a slow progressive decline in spike amplitude, noise amplitude, and number of viable channels that predicts complete signal loss by about eight years. Impedance measurements showed

  12. New materials and multidimensional cluster analysis for SAW chemical sensor arrays

    SciTech Connect

    Ricco, A.J.; Osbourn, G.C.; Bartholomew, J.W.; Crooks, R.M.; Chuanjing, Xu; Allred, R.E.

    1994-05-01

    We use six-element arrays of 97-MHz ST-quartz surface acoustic wave (SAW) devices to detect changes in thin-film mass and mechanical properties resulting from sorption of analytes by films representing two new classes of chemical sensor interface: self-assembled monolayers (SAMs) and plasma-grafted films (PGFs). While these materials do not display exceptional chemical selectivity, various combinations of the 7 different SAMs and 8 PGFs examined to produce distinct response patterns for each of 13 analytes. The analytes include aliphatic, aromatic, and chlorinated hydrocarbons; alcohols; ketones; organophosphonates; and water. Evaluation of the SAW array data using multidimensional cluster analysis techniques show that each chemical species can be correctly identified 100% of the time over the 9%- to 49%-of-saturation range using data from many combinations of four or more films.

  13. On the thermoelastic analysis of solar cell arrays and related material properties

    NASA Technical Reports Server (NTRS)

    Salama, M. A.; Bouquet, F. L.

    1976-01-01

    Accurate prediction of failure of solar cell arrays requires accuracy in the computation of thermally induced stresses. This was accomplished by using the finite element technique. Improved procedures for stress calculation were introduced together with failure criteria capable of describing a wide range of ductile and brittle material behavior. The stress distribution and associated failure mechanisms in the N-interconnect junction of two solar cell designs were then studied. In such stress and failure analysis, it is essential to know the thermomechanical properties of the materials involved. Measurements were made of properties of materials suitable for the design of lightweight arrays: microsheet-0211 glass material for the solar cell filter, and Kapton-H, Kapton F, Teflon, Tedlar, and Mica Ply PG-402 for lightweight substrates. The temperature-dependence of the thermal coefficient of expansion for these materials was determined together with other properties such as the elastic moduli, Poisson's ratio, and the stress-strain behavior up to failure.

  14. Application of neural networks to digital pulse shape analysis for an array of silicon strip detectors

    NASA Astrophysics Data System (ADS)

    Flores, J. L.; Martel, I.; Jiménez, R.; Galán, J.; Salmerón, P.

    2016-09-01

    The new generation of nuclear physics detectors that used to study nuclear reactions is considering the use of digital pulse shape analysis techniques (DPSA) to obtain the (A,Z) values of the reaction products impinging in solid state detectors. This technique can be an important tool for selecting the relevant reaction channels at the HYDE (HYbrid DEtector ball array) silicon array foreseen for the Low Energy Branch of the FAIR facility (Darmstadt, Germany). In this work we study the feasibility of using artificial neural networks (ANNs) for particle identification with silicon detectors. Multilayer Perceptron networks were trained and tested with recent experimental data, showing excellent identification capabilities with signals of several isotopes ranging from 12C up to 84Kr, yielding higher discrimination rates than any other previously reported.

  15. Analysis of an industrial production suspension of Bacillus lentus subtilisin crystals by powder diffraction: a powerful quality-control tool.

    PubMed

    Frankaer, Christian G; Moroz, Olga V; Turkenburg, Johan P; Aspmo, Stein I; Thymark, Majbritt; Friis, Esben P; Stahl, Kenny; Nielsen, Jens E; Wilson, Keith S; Harris, Pernille

    2014-04-01

    A microcrystalline suspension of Bacillus lentus subtilisin (Savinase) produced during industrial large-scale production was analysed by X-ray powder diffraction (XRPD) and X-ray single-crystal diffraction (MX). XRPD established that the bulk microcrystal sample representative of the entire production suspension corresponded to space group P212121, with unit-cell parameters a = 47.65, b = 62.43, c = 75.74 Å, equivalent to those for a known orthorhombic crystal form (PDB entry 1ndq). MX using synchrotron beamlines at the Diamond Light Source with beam dimensions of 20 × 20 µm was subsequently used to study the largest crystals present in the suspension, with diffraction data being collected from two single crystals (∼20 × 20 × 60 µm) to resolutions of 1.40 and 1.57 Å, respectively. Both structures also belonged to space group P2(1)2(1)2(1), but were quite distinct from the dominant form identified by XRPD, with unit-cell parameters a = 53.04, b = 57.55, c = 71.37 Å and a = 52.72, b = 57.13, c = 65.86 Å, respectively, and refined to R = 10.8% and Rfree = 15.5% and to R = 14.1% and Rfree = 18.0%, respectively. They are also different from any of the forms previously reported in the PDB. A controlled crystallization experiment with a highly purified Savinase sample allowed the growth of single crystals of the form identified by XRPD; their structure was solved and refined to a resolution of 1.17 Å with an R of 9.2% and an Rfree of 11.8%. Thus, there are at least three polymorphs present in the production suspension, albeit with the 1ndq-like microcrystals predominating. It is shown how the two techniques can provide invaluable and complementary information for such a production suspension and it is proposed that XRPD provides an excellent quality-control tool for such suspensions.

  16. Marek's disease virus-induced immunosuppression: array analysis of chicken immune response gene expression profiling.

    PubMed

    Heidari, Mohammad; Sarson, Aimie J; Huebner, Marianne; Sharif, Shayan; Kireev, Dmitry; Zhou, Huaijun

    2010-06-01

    Marek's disease (MD) is a lymphoproliferative disease of chickens induced by a highly cell-associated oncogenic alpha-herpesvirus, Marek's disease virus (MDV). MDV replicates in chicken lymphocytes and establishes a latency infection within CD4(+) T cells. Host-virus interaction, immune responses to infection, and transcriptional profiling of chicken gene expression in MD are poorly understood. In this study we conducted a global host gene expression analysis in the splenocytes of MDV-infected chickens using oligonucleotide-based Affymetrix GeneChip Chicken Genome Arrays. These arrays contain probes for more than 32,000 chicken transcripts and most of the known MDV genes and open reading frames. Two-week-old MD-susceptible chickens were inoculated with an oncogenic strain of MDV, and spleen samples were collected 5 and 15 days post-infection (dpi) for RNA isolation and microarray analysis. Array results displayed a significant differential pattern of immune response transcriptome between the two phases of MDV infection. The expression levels of more than 22 immune-response and related genes were downregulated, while the expression levels of at least 58 genes were increased at 5 dpi (cytolytic infection), compared to age-matched control birds. In comparison, out of 73 immune-response and related genes, 67 genes were downregulated, with only 6 genes having higher expression levels at 15 dpi (latency infection). Cytokines, chemokines, MHC molecules and related receptors, and adhesion molecules were among the many MDV-induced downregulated genes that are critical for an effective antiviral immune response. In addition, several apoptosis-associated genes were decreased in expression during latent infection, suggesting an MDV-induced blocking of initiation or progression of programmed cell death processes. These chicken arrays are valuable tools in understanding the molecular mechanisms behind viral pathogenesis and chicken gene expression patterns, and associated

  17. ASTRI SST-2M prototype and mini-array data reconstruction and scientific analysis software in the framework of the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Lombardi, Saverio; Antonelli, Lucio A.; Bastieri, Denis; Donnarumma, Imma; Lucarelli, Fabrizio; Madonna, Alberto; Mastropietro, Michele

    2016-07-01

    In the framework of the international Cherenkov Telescope Array (CTA) gamma-ray observatory, the Italian National Institute for Astrophysics (INAF) is developing a dual-mirror, small-sized, end-to-end prototype (ASTRI SST-2M), inaugurated on September 2014 at Mt. Etna (Italy), and a mini-array composed of nine ASTRI telescopes, proposed to be installed at the southern CTA site. The ASTRI mini-array is a collaborative effort led by INAF and carried out by institutes from Italy, Brazil, and South-Africa. The project is also including the full data handling chain from raw data up to final scientific products. To this end, a dedicated software for the online/ on-site/off-site data reconstruction and scientific analysis is under development for both the ASTRI SST-2M prototype and mini-array. The software is designed following a modular approach in which each single component and the entire pipeline are developed in compliance with the CTA requirements. Data reduction is conceived to be run on parallel computing architectures, as multi-core CPUs and graphic accelerators (GPUs), and new hardware architectures based on low-power consumption processors (e.g. ARM). The software components are coded in C++/Python/CUDA and wrapped by efficient pipelines written in Python. The final scientific products are then achieved by means of either science tools currently being used in the CTA Consortium (e.g. ctools) or specifically developed ones. In this contribution, we present the framework and the main software components of the ASTRI SST-2M prototype and mini-array data reconstruction and scientific analysis software package, and report the status of its development.

  18. Magnetic Suspension Technology Development

    NASA Technical Reports Server (NTRS)

    Britcher, Colin

    1998-01-01

    This Cooperative Agreement, intended to support focused research efforts in the area of magnetic suspension systems, was initiated between NASA Langley Research Center (LaRC) and Old Dominion University (ODU) starting January 1, 1997. The original proposal called for a three-year effort, but funding for the second year proved to be unavailable, leading to termination of the agreement following a 5-month no-cost extension. This report covers work completed during the entire 17-month period of the award. This research built on work that had taken place over recent years involving both NASA LARC and the Principal Investigator (PI). The research was of a rather fundamental nature, although specific applications were kept in mind at all times, such as wind tunnel Magnetic Suspension and Balance Systems (MSBS), space payload pointing and vibration isolation systems, magnetic bearings for unconventional applications, magnetically levitated ground transportation and electromagnetic launch systems. Fundamental work was undertaken in areas such as the development of optimized magnetic configurations, analysis and modelling of eddy current effects, control strategies for magnetically levitated wind tunnel models and system calibration procedures. Despite the termination of this Cooperative Agreement, several aspects of the research work are currently continuing with alternative forms of support.

  19. Analysis and testing of an integrated semi-active seat suspension for both longitudinal and vertical vibration control

    NASA Astrophysics Data System (ADS)

    Bai, Xian-Xu; Jiang, Peng; Pan, Hui; Qian, Li-Jun

    2016-04-01

    An integrated semi-active seat suspension for both longitudinal and vertical vibration control is analyzed and tested in this paper. The seat suspension consists of a switching mechanism transforming both longitudinal and vertical motions into a rotary motion and a real-time damping-controllable system-a rotary magnetorheological (MR) damper working in pure shear mode and its corresponding control system. The switching mechanism employs the parallelogram frames as a motion guide which keeps the seat moving longitudinally and vertically. At the same time, both longitudinal and vertical motions are transformed into a reciprocating rotary motion that is transmitted to the rotary MR damper after an amplification by a gear mechanism. Both the longitudinal and vertical vibrations can be attenuated in real time through controlling the damping force (or torque) of the rotary MR damper. The mathematical model of the seat suspension system is established, simulated, and analyzed. The experimental test based on the test rig in Hefei University of Technology is implemented, and the results of simulation and experimental test are compared and analyzed.

  20. The Design and Analysis of Split Row-Column Addressing Array for 2-D Transducer

    PubMed Central

    Li, Xu; Jia, Yanping; Ding, Mingyue; Yuchi, Ming

    2016-01-01

    For 3-D ultrasound imaging, the row-column addressing (RCA) with 2N connections for an N × N 2-D array makes the fabrication and interconnection simpler than the fully addressing with N2 connections. However, RCA degrades the image quality because of defocusing in signal channel direction in the transmit event. To solve this problem, a split row-column addressing scheme (SRCA) is proposed in this paper. Rather than connecting all the elements in the signal channel direction together, this scheme divides the elements in the signal channel direction into several disconnected blocks, thus enables focusing beam access in both signal channel and switch channel directions. Selecting an appropriate split scheme is the key for SRCA to maintaining a reasonable tradeoff between the image quality and the number of connections. Various split schemes for a 32 × 32 array are fully investigated with point spread function (PSF) analysis and imaging simulation. The result shows the split scheme with five blocks (4, 6, 12, 6, and 4 elements of each block) can provide similar image quality to fully addressing. The splitting schemes for different array sizes from 16 × 16 to 96 × 96 are also discussed. PMID:27690029

  1. Enclosed pillar arrays integrated on a fluidic platform for on-chip separations and analysis

    SciTech Connect

    Lavrik, Nickolay V; Taylor, Lisa; Sepaniak, Michael

    2010-01-01

    Due to the difficulty of reliably producing sealed 3-D structures, few researchers have tackled the challenges of creating pillar beds suitable for miniaturized liquid phase separation systems. Herein, we describe an original processing sequence for the fabrication of enclosed pillar arrays integrated on a fluidic chip which, we believe, will further stimulate interest in this field. Our approach yields a mechanically robust enclosed pillar system that withstands mechanical impacts commonly incurred during processing, sealing and operation, resulting in a design particularly suitable for the research environment. A combination of a wafer-level fabrication sequence with chip-level elastomer bonding allows for chip reusability, an attractive and cost efficient advancement for research applications. The characteristic features in the implemented highly ordered pillar arrays are scalable to submicron dimensions. The proposed fluidic structures are suitable for handling picolitre sample volumes and offer prospects for substantial improvements in separation efficiency and permeability over traditional packed and monolithic columns. Our experimental observations indicate plate heights as low as 0.76 {mu}m for a 10 mm long pillar bed. Theoretical calculations confirm that ordered pillar arrays with submicron pore sizes combine superior analysis speed, picolitre sample volumes, high permeability and reasonably large plate numbers on a small footprint. In addition, we describe a fluidic interface that provides streamlined coupling of the fabricated structures with off-chip fluidic components.

  2. Ultrasensitive label-free DNA analysis using an electronic chip based on carbon nanotube nanoelectrode arrays

    NASA Astrophysics Data System (ADS)

    Koehne, Jessica; Chen, Hua; Li, Jun; Cassell, Alan M.; Ye, Qi; Tee Ng, Hou; Han, Jie; Meyyappan, M.

    2003-12-01

    We report the detection of DNA PCR amplicons using an ultrasensitive label-free electronic technique based on multiwalled carbon nanotube (MWNT) nanoelectrode arrays embedded in an SiO2 matrix. Specific PCR amplicons are reliably detected using electrochemical (EC) methods through allele-specific oligonucleotide hybridization. The inherent guanine bases in the DNA amplicon target of {\\sim }300 bases serve as signal moieties with the aid of Ru(bpy)32+ mediators, providing an amplified anodic current associated with the oxidation of guanine groups at the nanoelectrode surface. The reduced size and density of the nanoelectrode array provided by MWNTs dramatically improves the sensitivity of EC detection. In addition, the abundant guanine bases in target DNA produce a large signal. Less than {\\sim } 1000 target amplicons can be detected on a microspot, approaching the sensitivity limit of conventional laser-based fluorescence techniques. This method also eliminates the labelling requirement and makes the measurements much simpler. This platform can be employed for developing highly automated electronic chips with multiplex nanoelectrode arrays for quick DNA analysis.

  3. MIR Solar Array Return Experiment: Power Performance Measurements and Molecular Contamination Analysis Results

    NASA Technical Reports Server (NTRS)

    Visentine, James; Kinard, William; Brinker, David; Scheiman, David; Banks, Bruce; Albyn, Keith; Hornung, Steve; See, Thomas

    2001-01-01

    A solar array segment was recently removed from the Mir core module and returned for ground-based analysis. The segment, which is similar to the ones the Russians have provided for the FGB and Service Modules, was microscopically examined and disassembled by US and Russian science teams. Laboratory analyses have shown the segment to he heavily contaminated by an organic silicone coating, which was converted to an organic silicate film by reactions with atomic oxygen within the. orbital flight environment. The source of the contaminant was a silicone polymer used by the Russians as an adhesive and bonding agent during segment construction. During its life cycle, the array experienced a reduction in power performance from approx. 12%, when it was new and first deployed, to approx. 5%, when it was taken out of service. However, current-voltage measurements of three contaminated cells and three pristine, Russian standard cells have shown that very little degradation in solar array performance was due to the silicate contaminants on the solar cell surfaces. The primary sources of performance degradation is attributed to "thermal hot-spotting" or electrical arcing; orbital debris and micrometeoroid impacts; and possibly to the degradation of the solar cells and interconnects caused by radiation damage from high energy protons and electrons.

  4. Array painting: a protocol for the rapid analysis of aberrant chromosomes using DNA microarrays

    PubMed Central

    Gribble, Susan M; Ng, Bee Ling; Prigmore, Elena; Fitzgerald, Tomas; Carter, Nigel P

    2012-01-01

    Aarray painting is a technique that uses microarray technology to rapidly map chromosome translocation breakpoints. previous methods to map translocation breakpoints have used fluorescence in situ hybridization (FIsH) and have consequently been labor-intensive, time-consuming and restricted to the low breakpoint resolution imposed by the use of metaphase chromosomes. array painting combines the isolation of derivative chromosomes (chromosomes with translocations) and high-resolution microarray analysis to refine the genomic location of translocation breakpoints in a single experiment. In this protocol, we describe array painting by isolation of derivative chromosomes using a MoFlo flow sorter, amplification of these derivatives using whole-genome amplification and hybridization onto commercially available oligonucleotide microarrays. although the sorting of derivative chromosomes is a specialized procedure requiring sophisticated equipment, the amplification, labeling and hybridization of Dna is straightforward, robust and can be completed within 1 week. the protocol described produces good quality data; however, array painting is equally achievable using any combination of the available alternative methodologies for chromosome isolation, amplification and hybridization. PMID:19893508

  5. Solar array design based on shadow analysis for increasing net energy collection in a competition vehicle

    NASA Astrophysics Data System (ADS)

    Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo; Suárez-Castañeda, Nicolás; Gil-Herrera, Ana; Barrera-Velásquez, Jorge

    2015-01-01

    Photovoltaic (PV) applications such as in the architectural, automotive, and aerospace industries face design contradictions because they are expected to produce a lot of energy but are constrained by available area, surface shape, incident irradiance, shadows, and other aspects that have a negative influence on the energy produced by the solar panel. Solar competition vehicles are some of these challenging PV applications. The design of such solar arrays needs to consider efficiency evaluation in order to optimize space; it is difficult not to install solar modules in areas impacted by shadows. A design procedure for a solar array configuration based on shadow analysis for competition vehicles is presented. The principle is that shadows in moving objects can be simulated, since the vehicle, the earth and the sun are are moving in semipredictable patterns, thus net energy collection can be forecast. The case study presented is the solar array design of a vehicle that participated in the World Solar Challenge 2013. The obtained results illustrate how the employment of the procedure gives insights on important aspects to consider and also delivers qualitative and quantitative information for decision making. In addition, the experience in competition highlights some issues to be considered, modified, or improved in further vehicle designs.

  6. Monte Carlo analysis of the enhanced transcranial penetration using distributed near-infrared emitter array.

    PubMed

    Yue, Lan; Humayun, Mark S

    2015-08-01

    Transcranial near-infrared (NIR) treatment of neurological diseases has gained recent momentum. However, the low NIR dose available to the brain, which shows severe scattering and absorption of the photons by human tissues, largely limits its effectiveness in clinical use. Hereby, we propose to take advantage of the strong scattering effect of the cranial tissues by applying an evenly distributed multiunit emitter array on the scalp to enhance the cerebral photon density while maintaining each single emitter operating under the safe thermal limit. By employing the Monte Carlo method, we simulated the transcranial propagation of the array emitted light and demonstrated markedly enhanced intracranial photon flux as well as improved uniformity of the photon distribution. These enhancements are correlated with the source location, density, and wavelength of light. To the best of our knowledge, we present the first systematic analysis of the intracranial light field established by the scalp-applied multisource array and reveal a strategy for the optimization of the therapeutic effects of the NIR radiation.

  7. The Design and Analysis of Split Row-Column Addressing Array for 2-D Transducer.

    PubMed

    Li, Xu; Jia, Yanping; Ding, Mingyue; Yuchi, Ming

    2016-09-27

    For 3-D ultrasound imaging, the row-column addressing (RCA) with 2N connections for an N × N 2-D array makes the fabrication and interconnection simpler than the fully addressing with N² connections. However, RCA degrades the image quality because of defocusing in signal channel direction in the transmit event. To solve this problem, a split row-column addressing scheme (SRCA) is proposed in this paper. Rather than connecting all the elements in the signal channel direction together, this scheme divides the elements in the signal channel direction into several disconnected blocks, thus enables focusing beam access in both signal channel and switch channel directions. Selecting an appropriate split scheme is the key for SRCA to maintaining a reasonable tradeoff between the image quality and the number of connections. Various split schemes for a 32 × 32 array are fully investigated with point spread function (PSF) analysis and imaging simulation. The result shows the split scheme with five blocks (4, 6, 12, 6, and 4 elements of each block) can provide similar image quality to fully addressing. The splitting schemes for different array sizes from 16 × 16 to 96 × 96 are also discussed.

  8. Data in support of proteomic analysis of pneumococcal pediatric clinical isolates to construct a protein array

    PubMed Central

    Olaya-Abril, Alfonso; Obando, Ignacio; Rodríguez-Ortega, Manuel J.

    2016-01-01

    Surface proteins play key roles in the interaction between cells and their environment, and in pathogenic microorganisms they are the best targets for drug or vaccine discovery and/or development. In addition, surface proteins can be the basis for serodiagnostic tools aiming at developing more affordable techniques for early diagnosis of infection in patients. We carried out a proteomic analysis of a collection of pediatric clinical isolates of Streptococcus pneumoniae, an important human pathogen responsible for more than 1.5 million child deaths worldwide. For that, cultured live bacterial cells were “shaved” with trypsin, and the recovered peptides were analyzed by LC/MS/MS. We selected 95 proteins to be produced as recombinant polypeptides, and printed them on an array. We probed the protein array with a collection of patient sera to define serodiagnostic antigens. The mass spectrometry proteomics data correspond to those published in [1] and have been deposited to the ProteomeXchange Consortium [2] via the PRIDE partner repository [3] with the dataset identifier PXD001740. The protein array raw data are provided as supplemental material in this article. PMID:26949725

  9. Detection and Analysis of Low-Frequency Sperm Whale Vocalizations with a Towed Array

    NASA Astrophysics Data System (ADS)

    Bohn, Alexander

    Sperm whale vocalizations recorded during a sea test and calibration experiment in the Gulf of Maine on a single towed, horizontal, densely sampled, low-frequency (< 2500 Hz), coherent hydrophone array system are detected and analyzed for signal energy level and other characteristics. The vocalizing individuals are localized in bearing, range, and depth. An algorithm is developed to achieve automatic detection of vocalizations. This analysis is shown to have potential utility despite restriction to only the low-frequency component of the vocalizations by sampling theory. In addition, transmission loss in the New England continental shelf and slope environment is accounted for with an ocean waveguide-acoustic propagation model. Multiple averaged realizations of this model are used to estimate transmission loss as a function of range and depth for transects between the receiver array and vocalizing whales. Comparison of the vocalizations and background noise levels and the estimated transmission loss suggests the sperm whale detection range after coherent array processing exceeds 60 km in low-to-moderate sea states. Low-frequency source levels of vocalizations are estimated using the received levels and the estimated transmission loss, and applications of both this estimate and the receiver-side statistics are discussed.

  10. Integrated microfluidic array plate (iMAP) for cellular and molecular analysis.

    PubMed

    Dimov, Ivan K; Kijanka, Gregor; Park, Younggeun; Ducrée, Jens; Kang, Taewook; Lee, Luke P

    2011-08-21

    Just as the Petri dish has been invaluable to the evolution of biomedical science in the last 100 years, microfluidic cell assay platforms have the potential to change significantly the way modern biology and clinical science are performed. However, an evolutionary process of creating an efficient microfluidic array for many different bioassays is necessary. Specifically for a complete view of a cell response it is essential to incorporate cytotoxic, protein and gene analysis on a single system. Here we present a novel cellular and molecular analysis platform, which allows access to gene expression, protein immunoassay, and cytotoxicity information in parallel. It is realized by an integrated microfluidic array plate (iMAP). The iMAP enables sample processing of cells, perfusion based cell culture, effective perturbation of biologic molecules or drugs, and simultaneous, real-time optical analysis for different bioassays. The key features of the iMAP design are the interface of on-board gravity driven flow, the open access input fluid exchange and the highly efficient sedimentation based cell capture mechanism (∼100% capture rates). The operation of the device is straightforward (tube and pump free) and capable of handling dilute samples (5-cells per experiment), low reagent volumes (50 nL per reaction), and performing single cell protein and gene expression measurements. We believe that the unique low cell number and triple analysis capabilities of the iMAP platform can enable novel dynamic studies of scarce cells.

  11. Statistical Analysis of the Performance of MDL Enumeration for Multiple-Missed Detection in Array Processing.

    PubMed

    Du, Fei; Li, Yibo; Jin, Shijiu

    2015-08-18

    An accurate performance analysis on the MDL criterion for source enumeration in array processing is presented in this paper. The enumeration results of MDL can be predicted precisely by the proposed procedure via the statistical analysis of the sample eigenvalues, whose distributive properties are investigated with the consideration of their interactions. A novel approach is also developed for the performance evaluation when the source number is underestimated by a number greater than one, which is denoted as "multiple-missed detection", and the probability of a specific underestimated source number can be estimated by ratio distribution analysis. Simulation results are included to demonstrate the superiority of the presented method over available results and confirm the ability of the proposed approach to perform multiple-missed detection analysis.

  12. Statistical Analysis of the Performance of MDL Enumeration for Multiple-Missed Detection in Array Processing

    PubMed Central

    Du, Fei; Li, Yibo; Jin, Shijiu

    2015-01-01

    An accurate performance analysis on the MDL criterion for source enumeration in array processing is presented in this paper. The enumeration results of MDL can be predicted precisely by the proposed procedure via the statistical analysis of the sample eigenvalues, whose distributive properties are investigated with the consideration of their interactions. A novel approach is also developed for the performance evaluation when the source number is underestimated by a number greater than one, which is denoted as “multiple-missed detection”, and the probability of a specific underestimated source number can be estimated by ratio distribution analysis. Simulation results are included to demonstrate the superiority of the presented method over available results and confirm the ability of the proposed approach to perform multiple-missed detection analysis. PMID:26295232

  13. Using Solid State Disk Array as a Cache for LHC ATLAS Data Analysis

    NASA Astrophysics Data System (ADS)

    Yang, W.; Hanushevsky, A. B.; Mount, R. P.; Atlas Collaboration

    2014-06-01

    User data analysis in high energy physics presents a challenge to spinning-disk based storage systems. The analysis is data intense, yet reads are small, sparse and cover a large volume of data files. It is also unpredictable due to users' response to storage performance. We describe here a system with an array of Solid State Disk as a non-conventional, standalone file level cache in front of the spinning disk storage to help improve the performance of LHC ATLAS user analysis at SLAC. The system uses several days of data access records to make caching decisions. It can also use information from other sources such as a work-flow management system. We evaluate the performance of the system both in terms of caching and its impact on user analysis jobs. The system currently uses Xrootd technology, but the technique can be applied to any storage system.

  14. Array tomography: imaging stained arrays.

    PubMed

    Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J

    2010-11-01

    Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time-consuming and require some practice to perfect. In this protocol, tissue arrays are imaged using conventional wide-field fluorescence microscopy. Images can be captured manually or, with the appropriate software and hardware, the process can be automated.

  15. Array tomography: production of arrays.

    PubMed

    Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J

    2010-11-01

    Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time consuming and require some practice to perfect. This protocol describes the sectioning of embedded tissues and the mounting of the serial arrays. The procedures require some familiarity with the techniques used for ultramicrotome sectioning for electron microscopy.

  16. Metal oxide based multisensor array and portable database for field analysis of antioxidants

    PubMed Central

    Sharpe, Erica; Bradley, Ryan; Frasco, Thalia; Jayathilaka, Dilhani; Marsh, Amanda; Andreescu, Silvana

    2014-01-01

    We report a novel chemical sensing array based on metal oxide nanoparticles as a portable and inexpensive paper-based colorimetric method for polyphenol detection and field characterization of antioxidant containing samples. Multiple metal oxide nanoparticles with various polyphenol binding properties were used as active sensing materials to develop the sensor array and establish a database of polyphenol standards that include epigallocatechin gallate, gallic acid, resveratrol, and Trolox among others. Unique charge-transfer complexes are formed between each polyphenol and each metal oxide on the surface of individual sensors in the array, creating distinct optically detectable signals which have been quantified and logged into a reference database for polyphenol identification. The field-portable Pantone/X-Rite© CapSure® color reader was used to create this database and to facilitate rapid colorimetric analysis. The use of multiple metal-oxide sensors allows for cross-validation of results and increases accuracy of analysis. The database has enabled successful identification and quantification of antioxidant constituents within real botanical extractions including green tea. Formation of charge-transfer complexes is also correlated with antioxidant activity exhibiting electron transfer capabilities of each polyphenol. The antioxidant activity of each sample was calculated and validated against the oxygen radical absorbance capacity (ORAC) assay showing good comparability. The results indicate that this method can be successfully used for a more comprehensive analysis of antioxidant containing samples as compared to conventional methods. This technology can greatly simplify investigations into plant phenolics and make possible the on-site determination of antioxidant composition and activity in remote locations. PMID:24610993

  17. Model-based analysis of two-color arrays (MA2C)

    PubMed Central

    Song, Jun S; Johnson, W Evan; Zhu, Xiaopeng; Zhang, Xinmin; Li, Wei; Manrai, Arjun K; Liu, Jun S; Chen, Runsheng; Liu, X Shirley

    2007-01-01

    A novel normalization method based on the GC content of probes is developed for two-color tiling arrays. The proposed method, together with robust estimates of the model parameters, is shown to perform superbly on published data sets. A robust algorithm for detecting peak regions is also formulated and shown to perform well compared to other approaches. The tools have been implemented as a stand-alone Java program called MA2C, which can display various plots of statistical analysis for quality control. PMID:17727723

  18. Analysis and fabrication of corner cube array based on laser direct writing technology.

    PubMed

    Lou, Yimin; Wang, Hui; Liu, Qingkun; Shi, Yaocheng; He, Sailing

    2010-10-10

    A detailed analysis of corner cube array (CCA) structure is carried out using the commercially available ray-tracing software ZEMAX. The retroreflective properties of CCA for short-range and long-range propagation are compared. An improved CCA structure with a relatively low structural depth (compared with rectangular CCA) is designed and analyzed. Higher retroreflectance (compared with triangular CCA) at a specific incident angle is proved by ray tracing. Two kinds of CCA structures, including the improved CCA, have been fabricated using laser direct writing technology. The fabrication results are qualified by three-dimensional shape measurement and ray tracing.

  19. Low-volume multiplexed proteolytic activity assay and inhibitor analysis through a pico-injector array.

    PubMed

    Ng, Ee Xien; Miller, Miles A; Jing, Tengyang; Lauffenburger, Doug A; Chen, Chia-Hung

    2015-02-21

    Secreted active proteases, from families of enzymes such as matrix metalloproteinases (MMPs) and ADAMs (a disintegrin and metalloproteinases), participate in diverse pathological processes. To simultaneously measure multiple specific protease activities, a series of parallel enzyme reactions combined with a series of inhibitor analyses for proteolytic activity matrix analysis (PrAMA) are essential but limited due to the sample quantity requirements and the complexity of performing multiple reactions. To address these issues, we developed a pico-injector array to generate 72 different reactions in picoliter-volume droplets by controlling the sequence of combinational injections, which allowed simultaneous recording of a wide range of multiple enzyme reactions and measurement of inhibitor effects using small sample volumes (~10 μL). Multiple MMP activities were simultaneously determined by 9 different substrates and 2 inhibitors using injections from a pico-injector array. Due to the advantages of inhibitor analysis, the MMP/ADAM activities of MDA-MB-231, a breast cancer cell line, were characterized with high MMP-2, MMP-3 and ADAM-10 activity. This platform could be customized for a wide range of applications that also require multiple reactions with inhibitor analysis to enhance the sensitivity by encapsulating different chemical sensors.

  20. A Thermal Analysis Approach for the Mars Odyssey Spacecraft's Solar Array

    NASA Technical Reports Server (NTRS)

    Dec, John A.; Amundsen, Ruth M.

    2003-01-01

    There are numerous challenges associated with placing a spacecraft in orbit around Mars. Often. trades must be made such as the mass of the payload and the amount of fuel that can be carried. One technique employed to more efficiently place a spacecraft in orbit while maximizing payload mass (minimizing fuel use) is aerobraking. The Mars Odyssey Spacecraft made use of aerobraking to gradually reduce its orbit period from a highly elliptical insertion orbit to its final science orbit. Aerobraking introduces its own unique challenges, in particular, predicting the thermal response of the spacecraft and its components during each aerobraking drag pass. This paper describes the methods used to perform aerobraking thermal analysis using finite element thermal models of the Mars Odyssey Spacecraft's solar array. To accurately model the complex behavior during aerobraking, the thermal analysis must be tightly coupled to the spatially varying, time dependent aerodynamic heating analysis. Also, to properly represent the temperatures prior to the start of the drag pass. the model must include the orbital solar and planetary heat fluxes. It is critical that the thermal behavior be predicted accurately to maintain the solar array below its structural flight allowable temperature limit. The goal of this paper is to describe a thermal modeling method that was developed for this purpose.

  1. Collapsing granular suspensions.

    PubMed

    Kadau, D; Andrade, J S; Herrmann, H J

    2009-11-01

    A 2D contact dynamics model is proposed as a microscopic description of a collapsing suspension/soil to capture the essential physical processes underlying the dynamics of generation and collapse of the system. Our physical model is compared with real data obtained from in situ measurements performed with a natural collapsing/suspension soil. We show that the shear strength behavior of our collapsing suspension/soil model is very similar to the behavior of this collapsing suspension soil, for both the unperturbed and the perturbed phases of the material.

  2. Array Processing and Forward Modeling Methods for the Analysis of Stiffened, Fluid-Loaded Cylindrical Shells.

    NASA Astrophysics Data System (ADS)

    Bondaryk, Joseph E.

    This thesis investigates array processing and forward modeling methods for the analysis of experimental, structural acoustic data to understand wave propagation on fluid-loaded, elastic, cylindrical shells in the mid -frequency range, 2 < ka < 12. The transient, acoustic, in-plane, bistatic scattering response to wideband, plane waves at various angles of incidence was collected by a synthetic array for three shells, a finite, air-filled, empty thin shell, a duplicate shell stiffened with four unequally spaced ring-stiffeners and a duplicate ribbed shell augmented by resiliently-mounted, wave-bearing, internal structural elements. Array and signal processing techniques, including source deconvolution, array weighting, conventional focusing and the removal of the geometrically scattered contribution, are used to transform the collected data to a more easily interpreted representation. The resulting waveforms show that part of the transient, dynamic, structural response of the shell surface which is capable of radiating to the far field. Compressional membrane waves are directly observable in this representation and evidence of flexural membrane waves is present. Comparisons between the shells show energy compartmentalized by the ring stiffeners and coupled into the wave-bearing internals. Energy calculations show a decay rate of 30dB/msec due to radiation for the Empty shell but only 10dB/msec for the other shells at bow incidence. The Radon Transform is used to estimate the reflection coefficient of compressional waves at the shell endcap as 0.2. The measurement array does not provide enough resolution to allow use of this technique to determine the reflection, transmission and coupling coefficients at the ring stiffeners. Therefore, a forward modeling technique is used to further analyze the 0^ circ incidence case. This modeling couples a Transmission Line model of the shell with a Simulated Annealing approach to multi-dimensional, parameter estimation. This

  3. Microstamped Petri Dishes for Scanning Electrochemical Microscopy Analysis of Arrays of Microtissues

    PubMed Central

    Sridhar, Adithya; de Boer, Hans L.; van den Berg, Albert; Le Gac, Séverine

    2014-01-01

    While scanning electrochemical microscopy (SECM) is a powerful technique for non-invasive analysis of cells, SECM-based assays remain scarce and have been mainly limited so far to single cells, which is mostly due to the absence of suitable platform for experimentation on 3D cellular aggregates or microtissues. Here, we report stamping of a Petri dish with a microwell array for large-scale production of microtissues followed by their in situ analysis using SECM. The platform is realized by hot embossing arrays of microwells (200 μm depth; 400 μm diameter) in commercially available Petri dishes, using a PDMS stamp. Microtissues form spontaneously in the microwells, which is demonstrated here using various cell lines (e.g., HeLa, C2C12, HepG2 and MCF-7). Next, the respiratory activity of live HeLa microtissues is assessed by monitoring the oxygen reduction current in constant height mode and at various distances above the platform surface. Typically, at a 40 μm distance from the microtissue, a 30% decrease in the oxygen reduction current is measured, while above 250 μm, no influence of the presence of the microtissues is detected. After exposure to a model drug (50% ethanol), no such changes in oxygen concentration are found at any height in solution, which reflects that microtissues are not viable anymore. This is furthermore confirmed using conventional live/dead fluorescent stains. This live/dead assay demonstrates the capability of the proposed approach combining SECM and microtissue arrays formed in a stamped Petri dish for conducting cellular assays in a non-invasive way on 3D cellular models. PMID:24690887

  4. Ultrasensitive Label-free Electronic Chip for DNA Analysis Using Carbon Nanotube Nanoelectrode Arrays

    NASA Technical Reports Server (NTRS)

    Li, Jun; Koehne, Jessica; Chen, Hua; Cassell, Alan; Ng, Hou Tee; Ye, Qi; Han, Jie; Meyyappan, M.

    2004-01-01

    There is a strong need for faster, cheaper, and simpler methods for nucleic acid analysis in today s clinical tests. Nanotechnologies can potentially provide solutions to these requirements by integrating nanomaterials with biofunctionalities. Dramatic improvement in the sensitivity and multiplexing can be achieved through the high-degree miniaturization. Here, we present our study in the development of an ultrasensitive label-free electronic chip for DNA/RNA analysis based on carbon nanotube nanoelectrode arrays. A reliable nanoelectrode array based on vertically aligned multi-walled carbon nanotubes (MWNTs) embedded in a SiO2 matrix is fabricated using a bottom-up approach. Characteristic nanoelectrode behavior is observed with a low-density MWNT nanoelectrode array in measuring both the bulk and surface immobilized redox species. The open-end of MWNTs are found to present similar properties as graphite edge-plane electrodes, with a wide potential window, flexible chemical functionalities, and good biocompatibility. A BRCA1 related oligonucleotide probe with 18 bases is covalently functionalized at the open ends of the MWNTs and specifically hybridized with an oligonucleotide target as well as a PCR amplicon. The guanine bases in the target molecules are employed as the signal moieties for the electrochemical measurements. Ru(bpy)3(2+) mediator is used to further amplify the guanine oxidation signal. This technique has been employed for direct electrochemical detection of label-free PCR amplicon through specific hybridization with the BRCAl probe. The detection limit is estimated to be less than approximately 1000 DNA molecules, approaching the limit of the sensitivity by laser-based fluorescence techniques in DNA microarray. This system provides a general electronic platform for rapid molecular diagnostics in applications requiring ultrahigh sensitivity, high-degree of miniaturization, simple sample preparation, and low- cost operation.

  5. A review and analysis on growth and optical absorption properties of silicon nanowire array for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Sharma, Ritu; Dusad, Lalit Kumar

    2015-11-01

    In this paper, optical absorptions in silicon nanowires (SiNWs) arrays obtained from theoretical studies and experimental approaches have been reviewed. A brief description on the different growth techniques for SiNW arrays reported so far is presented. Comparative analysis based on major research findings has been done and the advantages of SiNW-based solar cells over thin film solar cells are presented. Furthermore, future aspects of the use of SiNWs for photovoltaic applications are discussed.

  6. Hindlimb suspension reduces muscle regeneration

    NASA Technical Reports Server (NTRS)

    Mozdziak, P. E.; Truong, Q.; Macius, A.; Schultz, E.

    1998-01-01

    Exposure of juvenile skeletal muscle to a weightless environment reduces growth and satellite cell mitotic activity. However, the effect of a weightless environment on the satellite cell population during muscle repair remains unknown. Muscle injury was induced in rat soleus muscles using the myotoxic snake venom, notexin. Rats were placed into hindlimb-suspended or weightbearing groups for 10 days following injury. Cellular proliferation during regeneration was evaluated using 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and image analysis. Hindlimb suspension reduced (P < 0.05) regenerated muscle mass, regenerated myofiber diameter, uninjured muscle mass, and uninjured myofiber diameter compared to weightbearing rats. Hindlimb suspension reduced (P < 0.05) BrdU labeling in uninjured soleus muscles compared to weight-bearing muscles. However, hindlimb suspension did not abolish muscle regeneration because myofibers formed in the injured soleus muscles of hindlimb-suspended rats, and BrdU labeling was equivalent (P > 0.10) on myofiber segments isolated from the soleus muscles of hindlimb-suspended and weightbearing rats following injury. Thus, hindlimb suspension (weightlessness) does not suppress satellite cell mitotic activity in regenerating muscles before myofiber formation, but reduces growth of the newly formed myofibers.

  7. A 48-pixel array of Single Photon Avalanche Diodes for multispot Single Molecule analysis.

    PubMed

    Gulinatti, Angelo; Rech, Ivan; Maccagnani, Piera; Ghioni, Massimo

    2013-02-04

    In this paper we present an array of 48 Single Photon Avalanche Diodes (SPADs) specifically designed for multispot Single Molecule Analysis. The detectors have been arranged in a 12×4 square geometry with a pitch-to-diameter ratio of ten in order to minimize the collection of the light from non-conjugated excitation spots. In order to explore the trade-offs between the detectors' performance and the optical coupling with the experimental setup, SPADs with an active diameter of 25 and of 50µm have been manufactured. The use of a custom technology, specifically designed for the fabrication of the detectors, allowed us to combine a high photon detection efficiency (peak close to 50% at a wavelength of 550nm) with a low dark count rate compatible with true single molecule detection. In order to allow easy integration into the optical setup for parallel single-molecule analysis, the SPAD array has been incorporated in a compact module containing all the electronics needed for a proper operation of the detectors.

  8. Pattern-recognition analysis of sensor arrays for toxic vapor detection

    SciTech Connect

    Rose-Pehrsson, S.L.

    1988-01-01

    A portable device was developed by Argonne National Laboratory to detect, identify, and warn personnel of the presence of hazardous gases and vapors. The prototype device uses an array of four different electrochemical sensors, which can be operated in four different modes, yielding 16 channels of data for each chemical species detected. Pattern recognition was used to determine the uniqueness of the information obtained and classification capacity of each channel. Analysis of a 22 vapor data set indicates that 10 channels provide unique information. An array of surface acoustic wave (SAW) devices coated with selectively sorbent materials has been investigated as a monitor for personnel safety where detection of hazardous vapors is required at sub-part-per-million (sub-ppm) concentrations in ambient air that can contain interferences at much higher concentration. Two large data sets were generated and studied. Principal component analysis demonstrates good separation of the different classes of chemical vapors tested. Hierarchical clustering provides evidence of the correlations between solubility properties and the observed clustering. Pattern recognition methods show that three to four sensors can adequately separate individual vapors of interest from interference vapors. A prediction set generated to test the linear discriminant indicated that all of the vapors are correctly identified, except water. Supervised learning techniques are used to reduce to eight the number of sensors necessary to identify the hazardous vapors in the presence of mixtures.

  9. Detecting seismic activity with a covariance matrix analysis of data recorded on seismic arrays

    NASA Astrophysics Data System (ADS)

    Seydoux, L.; Shapiro, N. M.; de Rosny, J.; Brenguier, F.; Landès, M.

    2016-03-01

    Modern seismic networks are recording the ground motion continuously at the Earth's surface, providing dense spatial samples of the seismic wavefield. The aim of our study is to analyse these records with statistical array-based approaches to identify coherent time-series as a function of time and frequency. Using ideas mainly brought from the random matrix theory, we analyse the spatial coherence of the seismic wavefield from the width of the covariance matrix eigenvalue distribution. We propose a robust detection method that could be used for the analysis of weak and emergent signals embedded in background noise, such as the volcanic or tectonic tremors and local microseismicity, without any prior knowledge about the studied wavefields. We apply our algorithm to the records of the seismic monitoring network of the Piton de la Fournaise volcano located at La Réunion Island and composed of 21 receivers with an aperture of ˜15 km. This array recorded many teleseismic earthquakes as well as seismovolcanic events during the year 2010. We show that the analysis of the wavefield at frequencies smaller than ˜0.1 Hz results in detection of the majority of teleseismic events from the Global Centroid Moment Tensor database. The seismic activity related to the Piton de la Fournaise volcano is well detected at frequencies above 1 Hz.

  10. Analysis and design of a multisensory array for explosive substances based on solid electrodes

    NASA Astrophysics Data System (ADS)

    Baron, Mark; Barrett, Richard; Rodriguez, Jose-Gonzalez

    2012-09-01

    The detection of explosives and explosive related compounds is a subject of importance in several areas including environmental health, de-mining efforts (land and sea) and security and defence against terrorist activity. The use of electrochemical methods is particularly attractive as many common explosives contain suitable chemical groups to be detected using electrochemical methods. The electrochemical detection of explosives and related compounds in solution using a virtual metal electrode array and differential pulse voltammetry was achieved. The multiple sets of voltammetric data were integrated using multivariate analysis and matched with known substances present in explosives. Seven explosive substances: 2,4-initrotoluene, 2,6-dinitrotoluene, 3,4-dinitrotoluene, 2-nitrotoluene , octogen (HMX), pentaerithrytol tetranitrate (PETN), trinitrotoluene (TNT) and cyclonite (RDX) and a taggant agent 2,3-dimethyl-2,3-dinitrobutane (DMNB) were subjected to analysis using four solid electrodes, namely glassy carbon, silver, gold and platinum in saline aqueous solutions to mimic an aquatic environment. The results obtained in Differential Pulse Voltammetry (DPV) from the different experiments with each electrode were combined to produce a single voltammogram, which was subjected to chemometric analysis using Partial Least Squares (PLS) and Principle Component Analysis Non-Iterative Partial Least Squares (PCA-NIPALS). A combination of the electrochemical signals obtained together with the use of chemometric analysis made it possible to discriminate between explosives and their mixtures and also to quantitate their concentration in saline solutions. These combinations created a mathematical array, which clearly separates the explosives, even if the electrochemical information is buried or mixed with the electrode background noise.

  11. Effects analysis of array geometry for resolving performance based on spatial average ambiguity function

    NASA Astrophysics Data System (ADS)

    Zha, Guofeng; Wang, Hongqiang; Cheng, Yongqiang; Qin, Yuliang

    2016-03-01

    For analyzing the three dimension (3D) spatial resolving performance of Multi-Transmitter Single-Receiver (MTSR) array radar with stochastic signals, the spatial average ambiguity function (SAAF) was introduced. The analytic expression of SAAF of array radar with stochastic is derived. To analyze the effects of array geometry, comparisons are implemented for three typical array geometries including circular, decussate and planar configuration. Simulated results illustrate that the spatial resolving performance is better for the circular array than that of others. Furthermore, it is shown that the array aperture size and the target's radial range are the main factors impacting the resolving performance.

  12. Large angle magnetic suspension test fixture

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P. (Principal Investigator); Huang, Jen-Kuang (Principal Investigator)

    1996-01-01

    Good progress is being made in several major areas. These include eddy current modelling and analysis, design optimization methods, wind tunnel Magnetic Suspension and Balance Systems (MSBS), payload pointing and vibration isolation systems, and system identification. In addition, another successful International Symposium has been completed, with the Proceedings being printed at the time of writing. These activities continue current work under this Grant and extend previous work on magnetic suspension systems and devices in the Guidance and Control Branch and will permit the demonstration of several new developments in the field of magnetic suspension technology.

  13. Failure mode analysis of silicon-based intracortical microelectrode arrays in non-human primates

    PubMed Central

    Barrese, James C; Rao, Naveen; Paroo, Kaivon; Triebwasser, Corey; Vargas-Irwin, Carlos; Franquemont, Lachlan; Donoghue, John P

    2016-01-01

    Objective Brain–computer interfaces (BCIs) using chronically implanted intracortical microelectrode arrays (MEAs) have the potential to restore lost function to people with disabilities if they work reliably for years. Current sensors fail to provide reliably useful signals over extended periods of time for reasons that are not clear. This study reports a comprehensive retrospective analysis from a large set of implants of a single type of intracortical MEA in a single species, with a common set of measures in order to evaluate failure modes. Approach Since 1996, 78 silicon MEAs were implanted in 27 monkeys (Macaca mulatta). We used two approaches to find reasons for sensor failure. First, we classified the time course leading up to complete recording failure as acute (abrupt) or chronic (progressive). Second, we evaluated the quality of electrode recordings over time based on signal features and electrode impedance. Failure modes were divided into four categories: biological, material, mechanical, and unknown. Main results Recording duration ranged from 0 to 2104 days (5.75 years), with a mean of 387 days and a median of 182 days (n = 78). Sixty-two arrays failed completely with a mean time to failure of 332 days (median = 133 days) while nine array experiments were electively terminated for experimental reasons (mean = 486 days). Seven remained active at the close of this study (mean = 753 days). Most failures (56%) occurred within a year of implantation, with acute mechanical failures the most common class (48%), largely because of connector issues (83%). Among grossly observable biological failures (24%), a progressive meningeal reaction that separated the array from the parenchyma was most prevalent (14.5%). In the absence of acute interruptions, electrode recordings showed a slow progressive decline in spike amplitude, noise amplitude, and number of viable channels that predicts complete signal loss by about eight years. Impedance measurements showed

  14. Single-strand conformation polymorphism analysis using capillary array electrophoresis for large-scale mutation detection.

    PubMed

    Larsen, Lars Allan; Jespersgaard, Cathrine; Andersen, Paal Skytt

    2007-01-01

    This protocol describes capillary array electrophoresis single-strand conformation polymorphism (CAE-SSCP), a screening method for detection of unknown and previously identified mutations. The method detects 98% of mutations in a sample material and can be applied to any organism where the goal is to determine genetic variation. This protocol describes how to screen for mutations in 192 singleplex or up to 768 multiplex samples over 3 days. The protocol is based on the principle of sequence-specific mobility of single-stranded DNA in a native polymer, and covers all stages in the procedure, from initial DNA purification to final CAE-SSCP data analysis, as follows: DNA is purified, followed by PCR amplification using fluorescent primers. After PCR amplification, double-stranded DNA is heat-denatured to separate the strands and subsequently cooled on ice to avoid reannealing. Finally, samples are analyzed by capillary electrophoresis and appropriate analysis software.

  15. Research on School Suspension

    ERIC Educational Resources Information Center

    Iselin, Anne-Marie

    2010-01-01

    Schools across the nation report increases in the use of punitive disciplinary methods (e.g., suspension). The need for these disciplinary practices to address serious student misconduct is undisputed. What research has questioned is why some students seem to be suspended more often than others, what effects suspension has on students, and whether…

  16. Comparative Proteomic Analysis of Cultured Suspension Cells of the Halophyte Halogeton glomeratus by iTRAQ Provides Insights into Response Mechanisms to Salt Stress

    PubMed Central

    Wang, Juncheng; Yao, Lirong; Li, Baochun; Meng, Yaxiong; Ma, Xiaole; Lai, Yong; Si, Erjing; Ren, Panrong; Yang, Ke; Shang, Xunwu; Wang, Huajun

    2016-01-01

    Soil salinity severely threatens land use capability and crop yields worldwide. An analysis of the molecular mechanisms of salt tolerance in halophytes will contribute to the development of salt-tolerant crops. In this study, a combination of physiological characteristics and iTRAQ-based proteomic approaches was conducted to investigate the molecular mechanisms underlying the salt response of suspension cell cultures of halophytic Halogeton glomeratus. These cells showed halophytic growth responses comparable to those of the whole plant. In total, 97 up-regulated proteins and 192 down-regulated proteins were identified as common to both 200 and 400 mM NaCl concentration treatments. Such salinity responsive proteins were mainly involved in energy, carbohydrate metabolism, stress defense, protein metabolism, signal transduction, cell growth, and cytoskeleton metabolism. Effective regulatory protein expression related to energy, stress defense, and carbohydrate metabolism play important roles in the salt-tolerance of H. glomeratus suspension cell cultures. However, known proteins regulating Na+ efflux from the cytoplasm and its compartmentalization into the vacuole did not change significantly under salinity stress suggesting our existing knowledge concerning Na+ extrusion and compartmentalization in halophytes needs to be evaluated further. Such data are discussed in the context of our current understandings of the mechanisms involved in the salinity response of the halophyte, H. glomeratus. PMID:26904073

  17. A study on the impact of hydroxypropyl methylcellulose on the viscosity of PEG melt suspensions using surface plots and principal component analysis.

    PubMed

    Oh, Ching Mien; Heng, Paul Wan Sia; Chan, Lai Wah

    2015-04-01

    An understanding of the rheological behaviour of polymer melt suspensions is crucial in pharmaceutical manufacturing, especially when processed by spray congealing or melt extruding. However, a detailed comparison of the viscosities at each and every temperature and concentration between the various grades of adjuvants in the formulation will be tedious and time-consuming. Therefore, the statistical method, principal component analysis (PCA), was explored in this study. The composite formulations comprising polyethylene glycol (PEG) 3350 and hydroxypropyl methylcellulose (HPMC) of ten different grades (K100 LV, K4M, K15M, K100M, E15 LV, E50 LV, E4M, F50 LV, F4M and Methocel VLV) at various concentrations were prepared and their viscosities at different temperatures determined. Surface plots showed that concentration of HPMC had a greater effect on the viscosity compared to temperature. Particle size and size distribution of HPMC played an important role in the viscosity of melt suspensions. Smaller particles led to a greater viscosity than larger particles. PCA was used to evaluate formulations of different viscosities. The complex viscosity profiles of the various formulations containing HPMC were successfully classified into three clusters of low, moderate and high viscosity. Formulations within each group showed similar viscosities despite differences in grade or concentration of HPMC. Formulations in the low viscosity cluster were found to be sprayable. PCA was able to differentiate the complex viscosity profiles of different formulations containing HPMC in an efficient and time-saving manner and provided an excellent visualisation of the data.

  18. Analysis of MMIC arrays for use in the ACTS Aero Experiment

    NASA Technical Reports Server (NTRS)

    Zimmerman, M.; Lee, R.; Rho, E.; Zaman, Z.

    1993-01-01

    The Aero Experiment is designed to demonstrate communication from an aircraft to an Earth terminal via the ACTS. This paper describes the link budget and antenna requirements for a 4.8 kbps full-duplex voice link at Ka-Band frequencies. Three arrays, one transmit array developed by TI and two receive arrays developed by GE and Boeing, were analyzed. The predicted performance characteristics of these arrays are presented and discussed in the paper.

  19. Computationally efficient analysis of extraordinary optical transmission through infinite and truncated subwavelength hole arrays

    NASA Astrophysics Data System (ADS)

    Camacho, Miguel; Boix, Rafael R.; Medina, Francisco

    2016-06-01

    The authors present a computationally efficient technique for the analysis of extraordinary transmission through both infinite and truncated periodic arrays of slots in perfect conductor screens of negligible thickness. An integral equation is obtained for the tangential electric field in the slots both in the infinite case and in the truncated case. The unknown functions are expressed as linear combinations of known basis functions, and the unknown weight coefficients are determined by means of Galerkin's method. The coefficients of Galerkin's matrix are obtained in the spatial domain in terms of double finite integrals containing the Green's functions (which, in the infinite case, is efficiently computed by means of Ewald's method) times cross-correlations between both the basis functions and their divergences. The computation in the spatial domain is an efficient alternative to the direct computation in the spectral domain since this latter approach involves the determination of either slowly convergent double infinite summations (infinite case) or slowly convergent double infinite integrals (truncated case). The results obtained are validated by means of commercial software, and it is found that the integral equation technique presented in this paper is at least two orders of magnitude faster than commercial software for a similar accuracy. It is also shown that the phenomena related to periodicity such as extraordinary transmission and Wood's anomaly start to appear in the truncated case for arrays with more than 100 (10 ×10 ) slots.

  20. Protein array based interactome analysis of amyloid-β indicates an inhibition of protein translation.

    PubMed

    Virok, Dezso P; Simon, Dóra; Bozsó, Zsolt; Rajkó, Róbert; Datki, Zsolt; Bálint, Éva; Szegedi, Viktor; Janáky, Tamás; Penke, Botond; Fülöp, Lívia

    2011-04-01

    Oligomeric amyloid-β is currently of interest in amyloid-β mediated toxicity and the pathogenesis of Alzheimer's disease. Mapping the amyloid-β interaction partners could help to discover novel pathways in disease pathogenesis. To discover the amyloid-β interaction partners, we applied a protein array with more than 8100 unique recombinantly expressed human proteins. We identified 324 proteins as potential interactors of oligomeric amyloid-β. The Gene Ontology functional analysis of these proteins showed that oligomeric amyloid-β bound to multiple proteins with diverse functions both from extra and intracellular localizations. This undiscriminating binding phenotype indicates that multiple protein interactions mediate the toxicity of the oligomeric amyloid-β. The most highly impacted cellular system was the protein translation machinery. Oligomeric amyloid-β could bind to altogether 24 proteins involved in translation initiation and elongation. The binding of amyloid-β to purified rat hippocampal ribosomes validated the protein array results. More importantly, in vitro translation assays showed that the oligomeric amyloid-β had a concentration dependent inhibitory activity on translation. Our results indicate that the inhibited protein synthesis is one of the pathways that can be involved in the amyloid-beta induced neurotoxicity.

  1. Modelling the signature of clustered airguns and analysis on the directivity of an airgun array

    NASA Astrophysics Data System (ADS)

    Li, Guofa; Cao, Mingqiang; Chen, Haolin; Ni, Chengzhou

    2011-03-01

    Based on the Giles-Johnston approximation and the analysis of the mutual interaction between two bubbles at different distances, a model is established to simulate the signature of clustered airguns in offshore seismic exploration, concerning the practical factors which have effects on bubble oscillation such as the gun ports throttling and the heat conduction across the bubble wall. By using this model, the signatures of clustered airguns at different distances are calculated with the volume of airguns equal and unequal; the energy distribution of the airgun array signature in three-dimensional (3D) space is also analysed. The result of simulation indicates (1) the pressure wave emitted from bubble oscillation and the ghost wave reflected from the sea surface change the wave field around other bubbles, which makes it the primary source of the mutual interaction between bubbles; (2) with the distance decreasing, the mutual interaction between bubbles becomes strong, the bubble period increases, the primary peak amplitude decreases, and the primary/bubble peak amplitude ratio increases at first and then decreases afterwards; (3) as the distance between bubbles reduced, the bubbles with unequal volumes oscillate with the same period, and the frequency locking phenomenon occurs accompanying the violent bubble oscillation; and (4) the energy of the pressure wave is strongest down below the midpoint of the airgun array, while relatively weak in other directions, this can be used for true amplitude recovery in seismic data processing.

  2. Photocatalytically patterned TiO2 arrays for on-plate selective enrichment of phosphopeptides and direct MALDI MS analysis.

    PubMed

    Wang, Hui; Duan, Jicheng; Cheng, Quan

    2011-03-01

    We report the development of photocatalytically patterned TiO(2) arrays for selective on-plate enrichment and direct matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of phosphopeptides. A thin TiO(2) nanofilm with controlled porosity is prepared on gold-covered glass slides by a layer-by-layer (LbL) deposition/calcination process. The highly porous and rough nanostructure offers high surface area for selective binding of phosphorylated species. The patterned arrays are generated using an octadecyltrichlorosilane (OTS) coating in combination of UV irradiation with a photomask, followed by NaOH etching. The resulting hydrophilic TiO(2) spots are thus surrounded by a hydrophobic OTS layer, which can facilitate the enrichment of low-abundance components by confining a large volume sample into a small area. The TiO(2) arrays exhibit high specificity toward phosphopeptides in complex samples including phosphoprotein digests and human serum, and the detection can be made in the fmole range. Additional advantages of the arrays include excellent stability, reusability/reproducibility, and low cost. This method has been successfully applied to the analysis of phosphopeptides in nonfat milk. The patterned TiO(2) arrays provide an attractive interface for performing on-plate reactions, including selective capture of target species for MALDI-MS analysis, and can serve as a versatile lab-on-a-chip platform for high throughput analysis in phosphoproteome research.

  3. Exome Array Analysis Identifies a Common Variant in IL27 Associated with Chronic Obstructive Pulmonary Disease

    PubMed Central

    Parker, Margaret M.; Chen, Han; Lao, Taotao; Hardin, Megan; Qiao, Dandi; Hawrylkiewicz, Iwona; Sliwinski, Pawel; Yim, Jae-Joon; Kim, Woo Jin; Kim, Deog Kyeom; Castaldi, Peter J.; Hersh, Craig P.; Morrow, Jarrett; Celli, Bartolome R.; Pinto-Plata, Victor M.; Criner, Gerald J.; Marchetti, Nathaniel; Bueno, Raphael; Agustí, Alvar; Make, Barry J.; Crapo, James D.; Calverley, Peter M.; Donner, Claudio F.; Lomas, David A.; Wouters, Emiel F. M.; Vestbo, Jorgen; Paré, Peter D.; Levy, Robert D.; Rennard, Stephen I.; Zhou, Xiaobo; Laird, Nan M.; Lin, Xihong; Beaty, Terri H.; Silverman, Edwin K.

    2016-01-01

    Rationale: Chronic obstructive pulmonary disease (COPD) susceptibility is in part related to genetic variants. Most genetic studies have been focused on genome-wide common variants without a specific focus on coding variants, but common and rare coding variants may also affect COPD susceptibility. Objectives: To identify coding variants associated with COPD. Methods: We tested nonsynonymous, splice, and stop variants derived from the Illumina HumanExome array for association with COPD in five study populations enriched for COPD. We evaluated single variants with a minor allele frequency greater than 0.5% using logistic regression. Results were combined using a fixed effects meta-analysis. We replicated novel single-variant associations in three additional COPD cohorts. Measurements and Main Results: We included 6,004 control subjects and 6,161 COPD cases across five cohorts for analysis. Our top result was rs16969968 (P = 1.7 × 10−14) in CHRNA5, a locus previously associated with COPD susceptibility and nicotine dependence. Additional top results were found in AGER, MMP3, and SERPINA1. A nonsynonymous variant, rs181206, in IL27 (P = 4.7 × 10−6) was just below the level of exome-wide significance but attained exome-wide significance (P = 5.7 × 10−8) when combined with results from other cohorts. Gene expression datasets revealed an association of rs181206 and the surrounding locus with expression of multiple genes; several were differentially expressed in COPD lung tissue, including TUFM. Conclusions: In an exome array analysis of COPD, we identified nonsynonymous variants at previously described loci and a novel exome-wide significant variant in IL27. This variant is at a locus previously described in genome-wide associations with diabetes, inflammatory bowel disease, and obesity and appears to affect genes potentially related to COPD pathogenesis. PMID:26771213

  4. Tectonic Tremor analysis with the Taiwan Chelungpu-Fault Drilling Program (TCDP) downhole seismometer array

    NASA Astrophysics Data System (ADS)

    Lin, Y.; Hillers, G.; Ma, K.; Campillo, M.

    2011-12-01

    We study tectonic tremor activity in the Taichung area, Taiwan, analyzing continuous seismic records from 6 short-period sensors of the TCDP borehole array situated around 1 km depth. The low background noise level facilitates the detection of low-amplitude tectonic tremor and low-frequency earthquake (LFE) waveforms. We apply a hierarchical analysis to first detect transient amplitude increases, and to subsequently verify its tectonic origin, i.e. to associate it with tremor signals. The frequency content of tremor usually exceeds the background noise around 2-8 Hz; hence, in the first step, we use BHS1, BHS4 and BHS7 (top, center, bottom sensor) records to detect amplitude anomalies in this frequency range. We calculate the smoothed spectra of 30 second non-overlapping windows taken daily from 5 night time hours to avoid increased day time amplitudes associated with cultural activities. Amplitude detection is then performed on frequency dependent median values of 5 minute advancing, 10 minute long time windows, yielding a series of threshold dependent increased-energy spectra-envelopes, indicating teleseismic waveforms, potential tremor records, or other transients related to anthropogenic or natural sources. To verify the transients' tectonic origin, potential tremor waveforms detected by the amplitude method are manually picked in the time domain. We apply the Brown et al. (2008) LFE matched filter technique to three-component data from the 6 available sensors. Initial few-second templates are taken from the analyst-picked, minute-long segments, and correlated component-wise with 24-h data. Significantly increased similarity between templates and matched waveform segments is detected using the array-average 7-fold MAD measure. Harvested waveforms associated with this initial `weak' detection are stacked, and the thus created master templates are used in an iterative correlation procedure to arrive at robust LFE detections. The increased similarity of waveforms

  5. Induction and Analysis of the Alkaloid Mitragynine Content of a Mitragyna speciosa Suspension Culture System upon Elicitation and Precursor Feeding

    PubMed Central

    Mohamad Zuldin, Nor Nahazima; Said, Ikram Md.; Mohd Noor, Normah; Zainal, Zamri; Jin Kiat, Chew; Ismail, Ismanizan

    2013-01-01

    This study aimed to determine the effects of different concentrations and combinations of the phytohormones 2,4-dichlorophenoxy acetic acid (2,4-D), kinetin, 6-benzylaminopurine (BAP), and 1-naphthaleneacetic acid (NAA) on callus induction and to demonstrate the role of elicitors and exogenous precursors on the production of mitragynine in a Mitragyna speciosa suspension culture. The best callus induction was achieved from petiole explants cultured on WPM that was supplemented with 4 mg L−1 2, 4-D (70.83%). Calli were transferred to liquid media and agitated on rotary shakers to establish Mitragyna speciosa cell suspension cultures. The optimum settled cell volume was achieved in the presence of WPM that contained 3 mg L−1 2,4-D and 3% sucrose (9.47 ± 0.4667 mL). The treatment of cultures with different concentrations of yeast extract and salicylic acid for different inoculation periods revealed that the highest mitragynine content as determined by HPLC was achieved from the culture treated with 250 mg L−1 yeast extract (9.275 ± 0.082 mg L−1) that was harvested on day 6 of culturing; salicylic acid showed low mitragynine content in all concentrations used. Tryptophan and loganin were used as exogenous precursors; the highest level of mitragynine production was achieved in cultures treated with 3 μM tryptophan and harvested at 6 days (13.226 ± 1.98 mg L−1). PMID:24065873

  6. Induction and analysis of the alkaloid mitragynine content of a Mitragyna speciosa suspension culture system upon elicitation and precursor feeding.

    PubMed

    Mohamad Zuldin, Nor Nahazima; Said, Ikram Md; Mohd Noor, Normah; Zainal, Zamri; Jin Kiat, Chew; Ismail, Ismanizan

    2013-01-01

    This study aimed to determine the effects of different concentrations and combinations of the phytohormones 2,4-dichlorophenoxy acetic acid (2,4-D), kinetin, 6-benzylaminopurine (BAP), and 1-naphthaleneacetic acid (NAA) on callus induction and to demonstrate the role of elicitors and exogenous precursors on the production of mitragynine in a Mitragyna speciosa suspension culture. The best callus induction was achieved from petiole explants cultured on WPM that was supplemented with 4 mg L⁻¹ 2,4-D (70.83%). Calli were transferred to liquid media and agitated on rotary shakers to establish Mitragyna speciosa cell suspension cultures. The optimum settled cell volume was achieved in the presence of WPM that contained 3 mg L⁻¹ 2,4-D and 3% sucrose (9.47 ± 0.4667 mL). The treatment of cultures with different concentrations of yeast extract and salicylic acid for different inoculation periods revealed that the highest mitragynine content as determined by HPLC was achieved from the culture treated with 250 mg L⁻¹ yeast extract (9.275 ± 0.082 mg L⁻¹) that was harvested on day 6 of culturing; salicylic acid showed low mitragynine content in all concentrations used. Tryptophan and loganin were used as exogenous precursors; the highest level of mitragynine production was achieved in cultures treated with 3  μM tryptophan and harvested at 6 days (13.226 ± 1.98 mg L⁻¹).

  7. An Array of Qualitative Data Analysis Tools: A Call for Data Analysis Triangulation

    ERIC Educational Resources Information Center

    Leech, Nancy L.; Onwuegbuzie, Anthony J.

    2007-01-01

    One of the most important steps in the qualitative research process is analysis of data. The purpose of this article is to provide elements for understanding multiple types of qualitative data analysis techniques available and the importance of utilizing more than one type of analysis, thus utilizing data analysis triangulation, in order to…

  8. EUV stochastic noise analysis and LCDU mitigation by etching on dense contact-hole array patterns

    NASA Astrophysics Data System (ADS)

    Kim, Seo Min; Koo, Sunyoung; Park, Jun-Taek; Lim, Chang-Moon; Kim, Myoungsoo; Ahn, Chang-Nam; Fumar-Pici, Anita; Chen, Alek C.

    2014-04-01

    Experimental local CD uniformity (LCDU) of the dense contact-hole (CH) array pattern is statistically decomposed into stochastic noise, mask component, and metrology factor. Each component are compared quantitatively, and traced after etching to find how much improvement can be achieved by smoothing. Etch CDU gain factor is defined as the differential of etch CD by resist CD, and used to estimate etch CDU on resist CDU. Stochastic noise has influenced on not only LCDU but also local placement error (LPE) of each contact-hole. This LPE is also decomposed into its constituents in the same statistical way. As a result, stochastic noise is found to be the most dominant factor on LCDU and LPE. Etch LCDU is well expected by Etch Gain factor, but LPE seems to be kept same after etching. Fingerprints are derived from the repeating component and the boundary size for excluding proximity effect in analysis is investigated.

  9. Compartmentalized microchannel array for high-throughput analysis of single cell polarized growth and dynamics

    SciTech Connect

    Geng, Tao; Bredeweg, Erin L.; Szymanski, Craig J.; Liu, Bingwen; Baker, Scott E.; Orr, Galya; Evans, James E.; Kelly, Ryan T.

    2015-11-04

    Here, interrogating polarized growth is technologically challenging due to extensive cellular branching and uncontrollable environmental conditions in conventional assays. Here we present a robust and high-performance microfluidic system that enables observations of polarized growth with enhanced temporal and spatial control over prolonged periods. The system has built-in tunability and versatility to accommodate a variety of science applications requiring precisely controlled environments. Using the model filamentous fungus, Neurospora crassa, this microfluidic system enabled direct visualization and analysis of cellular heterogeneity in a clonal fungal cell population, nuclear distribution and dynamics at the subhyphal level, and quantitative dynamics of gene expression with single hyphal compartment resolution in response to carbon source starvation and exchange experiments. Although the microfluidic device is demonstrated on filamentous fungi, our technology is immediately extensible to a wide array of other biosystems that exhibit similar polarized cell growth with applications ranging from bioenergy production to human health.

  10. Compartmentalized microchannel array for high-throughput analysis of single cell polarized growth and dynamics

    PubMed Central

    Geng, Tao; Bredeweg, Erin L.; Szymanski, Craig J.; Liu, Bingwen; Baker, Scott E.; Orr, Galya; Evans, James E.; Kelly, Ryan T.

    2015-01-01

    Interrogating polarized growth is technologically challenging due to extensive cellular branching and uncontrollable environmental conditions in conventional assays. Here we present a robust and high-performance microfluidic system that enables observations of polarized growth with enhanced temporal and spatial control over prolonged periods. The system has built-in tunability and versatility to accommodate a variety of scientific applications requiring precisely controlled environments. Using the model filamentous fungus, Neurospora crassa, our microfluidic system enabled direct visualization and analysis of cellular heterogeneity in a clonal fungal cell population, nuclear distribution and dynamics at the subhyphal level, and quantitative dynamics of gene expression with single hyphal compartment resolution in response to carbon source starvation and exchange. Although the microfluidic device is demonstrated on filamentous fungi, the technology is immediately extensible to a wide array of other biosystems that exhibit similar polarized cell growth, with applications ranging from bioenergy production to human health. PMID:26530004

  11. Compartmentalized microchannel array for high-throughput analysis of single cell polarized growth and dynamics

    DOE PAGES

    Geng, Tao; Bredeweg, Erin L.; Szymanski, Craig J.; ...

    2015-11-04

    Here, interrogating polarized growth is technologically challenging due to extensive cellular branching and uncontrollable environmental conditions in conventional assays. Here we present a robust and high-performance microfluidic system that enables observations of polarized growth with enhanced temporal and spatial control over prolonged periods. The system has built-in tunability and versatility to accommodate a variety of science applications requiring precisely controlled environments. Using the model filamentous fungus, Neurospora crassa, this microfluidic system enabled direct visualization and analysis of cellular heterogeneity in a clonal fungal cell population, nuclear distribution and dynamics at the subhyphal level, and quantitative dynamics of gene expression withmore » single hyphal compartment resolution in response to carbon source starvation and exchange experiments. Although the microfluidic device is demonstrated on filamentous fungi, our technology is immediately extensible to a wide array of other biosystems that exhibit similar polarized cell growth with applications ranging from bioenergy production to human health.« less

  12. Customized Array Comparative Genomic Hybridization Analysis of 25 Phosphatase-encoding Genes in Colorectal Cancer Tissues

    PubMed Central

    LACZMANSKA, IZABELA; SKIBA, PAWEL; KARPINSKI, PAWEL; BEBENEK, MAREK; M. SASIADEK, MARIA

    2016-01-01

    Background/Aim: Molecular mechanisms of alterations in protein tyrosine phosphatases (PTPs) genes in cancer have been previously described and include chromosomal aberrations, gene mutations, and epigenetic silencing. However, little is known about small intragenic gains and losses that may lead to either changes in expression or enzyme activity and even loss of protein function. Materials and Methods: The aim of this study was to investigate 25 phosphatase genes using customized array comparative genomic hybridization in 16 sporadic colorectal cancer tissues. Results: The analysis revealed two unique small alterations: of 2 kb in PTPN14 intron 1 and of 1 kb in PTPRJ intron 1. We also found gains and losses of whole PTPs gene sequences covered by large chromosome aberrations. Conclusion: In our preliminary studies using high-resolution custom microarray we confirmed that PTPs are frequently subjected to whole-gene rearrangements in colorectal cancer, and we revealed that non-polymorphic intragenic changes are rare. PMID:28031238

  13. Tandem array of nanoelectronic readers embedded coplanar to a fluidic nanochannel for correlated single biopolymer analysis

    PubMed Central

    Lesser-Rojas, Leonardo; Sriram, K. K.; Liao, Kuo-Tang; Lai, Shui-Chin; Kuo, Pai-Chia; Chu, Ming-Lee; Chou, Chia-Fu

    2014-01-01

    We have developed a two-step electron-beam lithography process to fabricate a tandem array of three pairs of tip-like gold nanoelectronic detectors with electrode gap size as small as 9 nm, embedded in a coplanar fashion to 60 nm deep, 100 nm wide, and up to 150 μm long nanochannels coupled to a world-micro-nanofluidic interface for easy sample introduction. Experimental tests with a sealed device using DNA-protein complexes demonstrate the coplanarity of the nanoelectrodes to the nanochannel surface. Further, this device could improve transverse current detection by correlated time-of-flight measurements of translocating samples, and serve as an autocalibrated velocimeter and nanoscale tandem Coulter counters for single molecule analysis of heterogeneous samples. PMID:24753731

  14. Malignant canine mammary tumours: Preliminary genomic insights using oligonucleotide array comparative genomic hybridisation analysis.

    PubMed

    Santos, Marta; Dias-Pereira, Patrícia; Williams, Christina; Lopes, Carlos; Breen, Matthew

    2017-03-28

    Neoplastic mammary disease in female dogs represents a major health concern for dog owners and veterinarians, but the genomic basis of the disease is poorly understood. In this study, we performed high resolution oligonucleotide array comparative genomic hybridisation (oaCGH) to assess genome wide DNA copy number changes in 10 malignant canine mammary tumours from seven female dogs, including multiple tumours collected at one time from each of three female dogs. In all but two tumours, genomic imbalances were detected, with losses being more common than gains. Canine chromosomes 9, 22, 26, 27, 34 and X were most frequently affected. Dissimilar oaCGH ratio profiles were observed in multiple tumours from the same dogs, providing preliminary evidence for probable independent pathogenesis. Analysis of adjacent samples of one tumour revealed regional differences in the number of genomic imbalances, suggesting heterogeneity within tumours.

  15. Phase-based dispersion analysis for acoustic array borehole logging data.

    PubMed

    Assous, Said; Elkington, Peter; Linnett, Laurie

    2014-04-01

    A phase-based dispersion analysis method for velocity (slowness) extraction from guided waves recorded by an acoustic borehole logging tool in a geological formation is presented. The technique consists of acquiring waveforms from an array of receivers distributed along the tool and constructing the dispersion characteristic by processing in the frequency domain and exploiting phase information to measure the travel time for each frequency component. The approach is nonparametric and completely data-driven and provides high resolution estimates that do not rely on velocity guesses or assumptions regarding the type of modes. Results are free of the aliases and spurious modes which are characteristic of some prior approaches. Examples of dispersion estimation curves are presented using synthesized flexural waves and field data from wireline dipole sonic tools; results are compared with those from the weighted spectral semblance (WSS) and amplitude and phase slowness estimation (APES) methods to demonstrate the effectiveness and utility of the proposed method.

  16. The strong ground motion in Mexico City: array and borehole data analysis.

    NASA Astrophysics Data System (ADS)

    Roullé, A.; Chávez-García, F. J.

    2003-04-01

    Site response at Mexico City has been intensively studied for the last 15 years, since the disastrous 1985 earthquakes. After those events, more than 100 accelerographs were installed, and their data have been extremely useful in quantifying amplification and in the subsequent upgrading of the building code. However, detailed analysis of the wavefield has been hampered by the lack of absolute time in the records and the large spacing between stations in terms of dominant wavelengths. In 2001, thanks to the support of CONACYT, Mexico, a new dense accelerographic network was installed in the lake bed zone of Mexico City. The entire network, including an existing network of 3 surface and 2 borehole stations operated by CENAPRED, consists in 12 surface and 4 borehole stations (at 30, 102 and 50 meters). Each station has a 18 bits recorder and a GPS receiver so that the complete network is a 3D array with absolute time. The main objective of this array is to provide data that can help us to better understand the wavefield that propagates in Mexico City during large earthquakes. Last year, a small event of magnitude 6.0 was partially recorded by 6 of the 12 surface stations and all the borehole stations. We analysed the surface data using different array processing techniques such as f-k methods and MUSIC algorithm and the borehole ones using a cross-correlation method. For periods inferior to the site resonance period, the soft clay layer with very low propagation velocities (less than 500 m/s) and a possible multipathing rule the wavefield pattern. For the large period range, the dominant surface wave comes from the epicentral direction and propagates with a quicker velocity (more than 1500 m/s) that corresponds to the velocity of deep layers. The analysis of borehole data shows the presence of different quick wavetrains in the short period range that could correspond to the first harmonic modes of Rayleigh waves. To complete this study, four others events recorded in

  17. In-shoe plantar pressure measurement and analysis system based on fabric pressure sensing array.

    PubMed

    Shu, Lin; Hua, Tao; Wang, Yangyong; Qiao Li, Qiao; Feng, David Dagan; Tao, Xiaoming

    2010-05-01

    Spatial and temporal plantar pressure distributions are important and useful measures in footwear evaluation, athletic training, clinical gait analysis, and pathology foot diagnosis. However, present plantar pressure measurement and analysis systems are more or less uncomfortable to wear and expensive. This paper presents an in-shoe plantar pressure measurement and analysis system based on a textile fabric sensor array, which is soft, light, and has a high-pressure sensitivity and a long service life. The sensors are connected with a soft polymeric board through conductive yarns and integrated into an insole. A stable data acquisition system interfaces with the insole, wirelessly transmits the acquired data to remote receiver through Bluetooth path. Three configuration modes are incorporated to gain connection with desktop, laptop, or smart phone, which can be configured to comfortably work in research laboratories, clinics, sport ground, and other outdoor environments. A real-time display and analysis software is presented to calculate parameters such as mean pressure, peak pressure, center of pressure (COP), and shift speed of COP. Experimental results show that this system has stable performance in both static and dynamic measurements.

  18. Thermal Analysis and Correlation of the Mars Odyssey Spacecraft's Solar Array During Aerobraking Operations

    NASA Technical Reports Server (NTRS)

    Dec, John A.; Gasbarre, Joseph F.; George, Benjamin E.

    2002-01-01

    The Mars Odyssey spacecraft made use of multipass aerobraking to gradually reduce its orbit period from a highly elliptical insertion orbit to its final science orbit. Aerobraking operations provided an opportunity to apply advanced thermal analysis techniques to predict the temperature of the spacecraft's solar array for each drag pass. Odyssey telemetry data was used to correlate the thermal model. The thermal analysis was tightly coupled to the flight mechanics, aerodynamics, and atmospheric modeling efforts being performed during operations. Specifically, the thermal analysis predictions required a calculation of the spacecraft's velocity relative to the atmosphere, a prediction of the atmospheric density, and a prediction of the heat transfer coefficients due to aerodynamic heating. Temperature correlations were performed by comparing predicted temperatures of the thermocouples to the actual thermocouple readings from the spacecraft. Time histories of the spacecraft relative velocity, atmospheric density, and heat transfer coefficients, calculated using flight accelerometer and quaternion data, were used to calculate the aerodynamic heating. During aerobraking operations, the correlations were used to continually update the thermal model, thus increasing confidence in the predictions. This paper describes the thermal analysis that was performed and presents the correlations to the flight data.

  19. Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis

    SciTech Connect

    Gao, Wei; Emaminejad, Sam; Nyein, Hnin Yin Yin; Challa, Samyuktha; Chen, Kevin; Peck, Austin; Fahad, Hossain M.; Ota, Hiroki; Shiraki, Hiroshi; Kiriya, Daisuke; Lien, Der-Hsien; Brooks, George A.; Davis, Ronald W.; Javey, Ali

    2016-01-27

    We report that wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual’s state of health. Sampling human sweat, which is rich in physiological information13, could enable non-invasive monitoring. Previously reported sweat-based and other noninvasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state14–18. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanically flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Lastly, our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plasticbased sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing.

  20. Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis

    DOE PAGES

    Gao, Wei; Emaminejad, Sam; Nyein, Hnin Yin Yin; ...

    2016-01-27

    We report that wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual’s state of health. Sampling human sweat, which is rich in physiological information13, could enable non-invasive monitoring. Previously reported sweat-based and other noninvasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state14–18. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanicallymore » flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Lastly, our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plasticbased sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing.« less

  1. Optimization of capillary array electrophoresis single-strand conformation polymorphism analysis for routine molecular diagnostics.

    PubMed

    Jespersgaard, Cathrine; Larsen, Lars Allan; Baba, Shingo; Kukita, Yoji; Tahira, Tomoko; Christiansen, Michael; Vuust, Jens; Hayashi, Kenshi; Andersen, Paal Skytt

    2006-10-01

    Mutation screening is widely used for molecular diagnostics of inherited disorders. Furthermore, it is anticipated that the present and future identification of genetic risk factors for complex disorders will increase the need for high-throughput mutation screening technologies. Capillary array electrophoresis (CAE) SSCP analysis is a low-cost, automated method with a high throughput and high reproducibility. Thus, the method fulfills many of the demands to be met for application in routine molecular diagnostics. However, the need for performing the electrophoresis at three temperatures between 18 degrees C and 35 degrees C for achievement of high sensitivity is a disadvantage of the method. Using a panel of 185 mutant samples, we have analyzed the effect of sample purification, sample medium and separation matrix on the sensitivity of CAE-SSCP analysis to optimize the method for molecular diagnostic use. We observed different effects from sample purification and sample medium at different electrophoresis temperatures, probably reflecting the complex interplay between sequence composition, electrophoresis conditions and sensitivity in SSCP analysis. The effect on assay sensitivity from three different polymers was tested using a single electrophoresis temperature of 27 degrees C. The data suggest that a sensitivity of 98-99% can be obtained using a 10% long chain poly-N,N-dimethylacrylamide polymer.

  2. Analysis of Reverse Phase Protein Array Data: From Experimental Design towards Targeted Biomarker Discovery

    PubMed Central

    Wachter, Astrid; Bernhardt, Stephan; Beissbarth, Tim; Korf, Ulrike

    2015-01-01

    Mastering the systematic analysis of tumor tissues on a large scale has long been a technical challenge for proteomics. In 2001, reverse phase protein arrays (RPPA) were added to the repertoire of existing immunoassays, which, for the first time, allowed a profiling of minute amounts of tumor lysates even after microdissection. A characteristic feature of RPPA is its outstanding sample capacity permitting the analysis of thousands of samples in parallel as a routine task. Until today, the RPPA approach has matured to a robust and highly sensitive high-throughput platform, which is ideally suited for biomarker discovery. Concomitant with technical advancements, new bioinformatic tools were developed for data normalization and data analysis as outlined in detail in this review. Furthermore, biomarker signatures obtained by different RPPA screens were compared with another or with that obtained by other proteomic formats, if possible. Options for overcoming the downside of RPPA, which is the need to steadily validate new antibody batches, will be discussed. Finally, a debate on using RPPA to advance personalized medicine will conclude this article. PMID:27600238

  3. Analysis of dynamic optical arbitrary waveform generation based on three FBG arrays

    NASA Astrophysics Data System (ADS)

    Zhang, Ailing; Li, Changxiu

    2013-11-01

    A dynamic optical arbitrary waveform generation (O-AWG) structure based on three fiber Bragg grating (FBG) arrays is proposed and its performances are analyzed. The first two arrays are used for amplitude control. The third array is used for phase control. Dynamic O-AWG can be realized by adjusting fiber stretchers (FSs) in the second array and the third array. In this paper, it is demonstrated that the phase controller is independent from the amplitude controller to achieve less complicated FSs adjustment and more phase distortion tolerance. Moreover, phase controller can be used for compensating dispersion caused by the first two arrays, and it also can be used for pulse repetition rate multiplication (RRM), which is preferable to amplitude controller for RRM with regard to phase sensitivity.

  4. Surface-wave analysis and its application to determining crustal and mantle structure beneath regional arrays

    NASA Astrophysics Data System (ADS)

    Jin, Ge

    We develop several new techniques to better retrieve Earth's structure by analyzing seismic surface waves. These techniques are applied in regional studies to understand a variety of tectonic structures and geodynamic processes in Earth's crust and upper mantle. We create an automated method to retrieve surface-wave phase velocities using dense seismic arrays. The method is based on the notion of using cross-correlation to measure phase variations between nearby stations. Frequency-dependent apparent phase velocities are inverted from the phase-variation measurements via the Eikonal equation. The multi-pathing interference is corrected using amplitude measurements via the Helmholtz equation. The coherence between nearby-station waveforms, together with other data-selection criteria, helps to automate the entire process. We build up the Automated Surface-Wave Measuring System (ASWMS) that retrieves structural phase velocity directly from raw seismic waveforms for individual earthquakes without human intervention. This system is applied on the broad-band seismic data recorded by the USArray from 2006-2014, and obtain Rayleigh-wave phase-velocity maps at the periods of 20-100~s. In total around half million seismograms from 850 events are processed, generating about 4 million cross-correlation measurements. The maps correlate well with several published studies, including ambient-noise results at high frequency. At all frequencies, a significant contrast in Rayleigh-wave phase velocity between the tectonically active western US and the stable eastern US can be observed, with the phase-velocity variations in the western US being 1-2 times greater. The Love wave phase-velocity maps are also calculated. We find that overtone interference may produce systematic bias for the Love-wave phase-velocity measurements. We apply surface-wave analysis on the data collected by a temporary broad-band seismic array near the D'Entrecasteaux Island (DI), Papua New Guinea. The array

  5. Analysis of copper nanoparticles toxicity based on a stress-responsive bacterial biosensor array

    NASA Astrophysics Data System (ADS)

    Li, Fenfang; Lei, Chunyang; Shen, Qinpeng; Li, Lijun; Wang, Ming; Guo, Manli; Huang, Yan; Nie, Zhou; Yao, Shouzhuo

    2012-12-01

    The rapid development in nanoparticle production and application during the past decade requires an easy, rapid, and predictive screening method for nanoparticles toxicity assay. In this study, the toxicological effects and the source of toxicity of copper nanoparticles (CuNPs) are investigated based on a stress-responsive bacterial biosensor array. According to the responses of the biosensing strains, it is found that CuNPs induce not only oxidative stress in E. coli, but also protein damage, DNA damage, and cell membrane damage, and ultimately cause cell growth inhibition. Through enzyme detoxification analysis, the toxicological effects of CuNPs are traced to H2O2 generation from CuNPs. Rapid copper release from CuNPs and Cu(i) production are observed. The oxidation of the released Cu(i) has a close relation to H2O2 production, as tris-(hydroxypropyltriazolylmethyl) amine, the specific Cu(i) chelator, can largely protect the cells from the toxicity of CuNPs. In addition, the TEM study shows that CuNPs can be adsorbed and incepted fast by the cells. Comparatively, copper microparticles are relatively stable in the system and practically non-toxic, which indicates the importance of toxic estimation of materials at the nanoscale. In addition, the Cu(ii) ion can induce protein damage, membrane damage, and slight DNA damage only at a relatively high concentration. The current study reveals the preliminary mechanism of toxicity of CuNPs, and suggests that the stress-responsive bacterial biosensor array can be used as a simple and promising tool for rapid screening in vitro toxicity of nanoparticles and studying the primary mechanism of the toxicity.The rapid development in nanoparticle production and application during the past decade requires an easy, rapid, and predictive screening method for nanoparticles toxicity assay. In this study, the toxicological effects and the source of toxicity of copper nanoparticles (CuNPs) are investigated based on a stress

  6. Fragility in dense suspensions

    NASA Astrophysics Data System (ADS)

    Mari, Romain; Cates, Mike

    Dense suspensions can jam under shear when the volume fraction of solid material is large enough. In this work we investigate the mechanical properties of shear jammed suspensions with numerical simulations. In particular, we address the issue of the fragility of these systems, i.e., the type of mechanical response (elastic or plastic) they show when subject to a mechanical load differing from the one applied during their preparation history.

  7. Kinematic and dynamic analysis of the McPherson suspension with a planar quarter-car model

    NASA Astrophysics Data System (ADS)

    Hurel, Jorge; Mandow, Anthony; García-Cerezo, Alfonso

    2013-09-01

    McPherson suspension modelling poses a challenging problem due to its nonlinear asymmetric behaviour. The paper proposes a planar quarter-car analytical model that not only considers vertical motion of the sprung mass (chassis) but also: (i) rotation and translation for the unsprung mass (wheel assembly), (ii) wheel mass and its inertia moment about the longitudinal axis, and (iii) tyre damping and lateral deflection. This kinematic-dynamic model offers a solution to two important shortcomings of the conventional quarter-car model: it accounts for geometry and for tyre modelling. The paper offers a systematic development of the planar model as well as the complete set of mathematical equations. This analytical model can be suitable for fast computation in hardware-in-the-loop applications. Furthermore, a reproducible Simulink implementation is given. The model has been compared with a realistic Adams/View simulation to analyse dynamic behaviour for the jounce and rebound motion of the wheel and two relevant kinematic parameters: camber angle and track width variation.

  8. A pharmacokinetic analysis of posaconazole oral suspension in the serum and alveolar compartment of lung transplant recipients.

    PubMed

    Thakuria, L; Packwood, K; Firouzi, A; Rogers, P; Soresi, S; Habibi-Parker, K; Lyster, H; Zych, B; Garcia-Saez, D; Mohite, P; Patil, N; Sabashnikov, A; Capoccia, M; Chibvuri, M; Lamba, H; Tate, H; Carby, M; Simon, A; Leaver, N; Reed, A

    2016-01-01

    Invasive fungal infections cause significant morbidity and mortality after lung transplantation. Fungal prophylaxis following lung transplantation is not standardised, with transplant centres utilising a variety of regimens. Posaconazole is a broad-spectrum antifungal triazole that requires further investigation within the setting of lung transplantation. This prospective, single-centre, observational study explored the pharmacokinetics of posaconazole oral suspension (POS) in the early perioperative period following lung transplantation in 26 patients. Organ recipients were scheduled to receive 400mg POS twice daily for 6 weeks as primary antifungal prophylaxis. Therapeutic drug monitoring (TDM) of serum posaconazole levels was performed in accordance with local clinical protocols. Bronchoalveolar lavage fluid (BALF) was sampled during routine bronchoscopies. Posaconazole levels were measured both in serum and BALF using mass spectrometry. Posaconazole levels were highly variable within lung transplant recipients during the perioperative period and did not achieve 'steady-state'. Serum posaconazole concentrations positively correlated with levels within the BALF (r=0.5527; P=0.0105). Of the 26 patients, 10 failed to complete the study for multiple reasons and so the trial was terminated early. Unlike study findings in stable recipients, serum posaconazole levels rarely achieved steady-state in the perioperative period; however, they do reflect the concentrations within the airways of newly transplanted lungs. The role of POS as primary prophylaxis in the perioperative period is uncertain, but if used TDM may be helpful for determining attainment of therapeutic levels.

  9. Detection analysis of surface hydroxyl active sites and simulation calculation of the surface dissociation constants of aqueous diatomite suspensions

    NASA Astrophysics Data System (ADS)

    Ma, Shu-Cui; Wang, Zhi-Gang; Zhang, Ji-Lin; Sun, De-Hui; Liu, Gui-Xia

    2015-02-01

    The surface properties of the diatomite were investigated using nitrogen adsorption/deadsorption isotherms, TG-DSC, FTIR, and XPS, and surface protonation-deprotonation behavior was determined by continuous acid-base potentiometric titration technique. The diatomite sample with porous honeycomb structure has a BET specific surface area of 10.21 m2/g and large numbers of surface hydroxyl functional groups (i.e. tbnd Si-OH, tbnd Fe-OH, and tbnd Al-OH). These surface hydroxyls can be protonated or deprotonated depending on the pH of the suspension. The experimental potentiometric data in two different ionic strength solutions (0.1 and 0.05 mol/L NaCl) were fitted using ProtoFit GUI V2.1 program by applying diffuse double layer model (DLM) with three amphoteric sites and minimizing the sum of squares between a dataset derivative function and a model derivative function. The optimized surface parameters (i.e. surface dissociation constants (log K1, log K2) and surface site concentrations (log C)) of the sample were obtained. Based on the optimized surface parameters, the surface species distribution was calculated using Program-free PHREEQC 3.1.2. Thus, this work reveals considerable new information about surface protonation-deprotonation processes and surface adsorptive behaviors of the diatomite, which helps us to effectively use the cheap and cheerful diatomite clay adsorbent.

  10. Analysis of the Proteins Secreted from the Oryza meyeriana Suspension-Cultured Cells Induced by Xanthomonas oryzae pv. oryzae

    PubMed Central

    Chen, Xian; Dong, Yan; Yu, Chulang; Fang, XianPing; Deng, Zhiping; Yan, Chengqi; Chen, Jianping

    2016-01-01

    Oryza meyeriana, a wild species of rice from China, shows high resistance to Xanthomonas oryzae pv. oryzae (Xoo), the cause of rice bacterial blight, one of the most serious rice pathogens. To better understand the resistance mechanism, a proteomic study was conducted to identify changes in the proteins secreted in embryo cell suspension cultures in response to Xoo. After two-dimensional difference gel electrophoresis (2D-DIGE), 72 differentially expressed protein spots corresponding to 34 proteins were identified by Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry. Of the 34 proteins, 10 were up regulated and 24 down regulated. The secreted proteins identified were predicted to be involved in various biological processes, including signal transduction, defense, ROS and cell wall modification. 77% of the 34 proteins were predicted to have a signal peptide by Signal P. Quantitative Real-Time PCR showed that transcript levels of 14 secreted proteins were not well correlated with secreted protein levels. Peroxidase activity was up regulated in both O. meyriana and susceptible rice but was about three times higher in O. meyeriana. This suggests that peroxidases may play an important role in the early response to Xoo in O. meyeriana. These results not only provide a better understanding of the resistance mechanism of O. meyeriana, but have implications for studies of the interactions between other plants and their pathogens. PMID:27196123

  11. Mechanisms of mosaicism, chimerism and uniparental disomy identified by single nucleotide polymorphism array analysis

    PubMed Central

    Conlin, Laura K.; Thiel, Brian D.; Bonnemann, Carsten G.; Medne, Livija; Ernst, Linda M.; Zackai, Elaine H.; Deardorff, Matthew A.; Krantz, Ian D.; Hakonarson, Hakon; Spinner, Nancy B.

    2010-01-01

    Mosaic aneuploidy and uniparental disomy (UPD) arise from mitotic or meiotic events. There are differences between these mechanisms in terms of (i) impact on embryonic development; (ii) co-occurrence of mosaic trisomy and UPD and (iii) potential recurrence risks. We used a genome-wide single nucleotide polymorphism (SNP) array to study patients with chromosome aneuploidy mosaicism, UPD and one individual with XX/XY chimerism to gain insight into the developmental mechanism and timing of these events. Sixteen cases of mosaic aneuploidy originated mitotically, and these included four rare trisomies and all of the monosomies, consistent with the influence of selective factors. Five trisomies arose meiotically, and three of the five had UPD in the disomic cells, confirming increased risk for UPD in the case of meiotic non-disjunction. Evidence for the meiotic origin of aneuploidy and UPD was seen in the patterns of recombination visible during analysis with 1–3 crossovers per chromosome. The mechanisms of formation of the UPD included trisomy rescue, with and without concomitant trisomy, monosomy rescue, and mitotic formation of a mosaic segmental UPD. UPD was also identified in an XX/XY chimeric individual, with one cell line having complete maternal UPD consistent with a parthenogenetic origin. Utilization of SNP arrays allows simultaneous evaluation of genomic alterations and insights into aneuploidy and UPD mechanisms. Differentiation of mitotic and meiotic origins for aneuploidy and UPD supports existence of selective factors against full trisomy of some chromosomes in the early embryo and provides data for estimation of recurrence and disease mechanisms. PMID:20053666

  12. Analysis of copper nanoparticles toxicity based on a stress-responsive bacterial biosensor array.

    PubMed

    Li, Fenfang; Lei, Chunyang; Shen, Qinpeng; Li, Lijun; Wang, Ming; Guo, Manli; Huang, Yan; Nie, Zhou; Yao, Shouzhuo

    2013-01-21

    The rapid development in nanoparticle production and application during the past decade requires an easy, rapid, and predictive screening method for nanoparticles toxicity assay. In this study, the toxicological effects and the source of toxicity of copper nanoparticles (CuNPs) are investigated based on a stress-responsive bacterial biosensor array. According to the responses of the biosensing strains, it is found that CuNPs induce not only oxidative stress in E. coli, but also protein damage, DNA damage, and cell membrane damage, and ultimately cause cell growth inhibition. Through enzyme detoxification analysis, the toxicological effects of CuNPs are traced to H(2)O(2) generation from CuNPs. Rapid copper release from CuNPs and Cu(I) production are observed. The oxidation of the released Cu(I) has a close relation to H(2)O(2) production, as tris-(hydroxypropyltriazolylmethyl) amine, the specific Cu(I) chelator, can largely protect the cells from the toxicity of CuNPs. In addition, the TEM study shows that CuNPs can be adsorbed and incepted fast by the cells. Comparatively, copper microparticles are relatively stable in the system and practically non-toxic, which indicates the importance of toxic estimation of materials at the nanoscale. In addition, the Cu(II) ion can induce protein damage, membrane damage, and slight DNA damage only at a relatively high concentration. The current study reveals the preliminary mechanism of toxicity of CuNPs, and suggests that the stress-responsive bacterial biosensor array can be used as a simple and promising tool for rapid screening in vitro toxicity of nanoparticles and studying the primary mechanism of the toxicity.

  13. Modelling and Analysis of Electrical Potentials Recorded in Microelectrode Arrays (MEAs).

    PubMed

    Ness, Torbjørn V; Chintaluri, Chaitanya; Potworowski, Jan; Łęski, Szymon; Głąbska, Helena; Wójcik, Daniel K; Einevoll, Gaute T

    2015-10-01

    Microelectrode arrays (MEAs), substrate-integrated planar arrays of up to thousands of closely spaced metal electrode contacts, have long been used to record neuronal activity in in vitro brain slices with high spatial and temporal resolution. However, the analysis of the MEA potentials has generally been mainly qualitative. Here we use a biophysical forward-modelling formalism based on the finite element method (FEM) to establish quantitatively accurate links between neural activity in the slice and potentials recorded in the MEA set-up. Then we develop a simpler approach based on the method of images (MoI) from electrostatics, which allows for computation of MEA potentials by simple formulas similar to what is used for homogeneous volume conductors. As we find MoI to give accurate results in most situations of practical interest, including anisotropic slices covered with highly conductive saline and MEA-electrode contacts of sizable physical extensions, a Python software package (ViMEAPy) has been developed to facilitate forward-modelling of MEA potentials generated by biophysically detailed multicompartmental neurons. We apply our scheme to investigate the influence of the MEA set-up on single-neuron spikes as well as on potentials generated by a cortical network comprising more than 3000 model neurons. The generated MEA potentials are substantially affected by both the saline bath covering the brain slice and a (putative) inadvertent saline layer at the interface between the MEA chip and the brain slice. We further explore methods for estimation of current-source density (CSD) from MEA potentials, and find the results to be much less sensitive to the experimental set-up.

  14. Analysis of Conical Wire Array Z-Pinch Stability with a Center Wire

    SciTech Connect

    Martinez, D.; Presura, R.; Wright, S.; Plechaty, C.; Neff, S.; Wanex, L.; Ampleford, D. J.

    2009-01-21

    Adding a center wire on the axis of a conical wire array produces conditions suitable for studying shear flow stabilization of the Z-pinch. The conical wire array produces and axial plasma flow while the center wire introduces a radial variation of the axial velocity. Experiments of this array configuration were preformed on the 1 MA Zebra Z-pinch generator and showed stabilization of the kink instability when a center wire was present. Comparison with equivalent cylindrical wire arrays indicates that the shear flow stabilization plays a role in the stabilization of the kink instability.

  15. ARRAY OPTIMIZATION FOR TIDAL ENERGY EXTRACTION IN A TIDAL CHANNEL – A NUMERICAL MODELING ANALYSIS

    SciTech Connect

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea

    2014-04-18

    This paper presents an application of a hydrodynamic model to simulate tidal energy extraction in a tidal dominated estuary in the Pacific Northwest coast. A series of numerical experiments were carried out to simulate tidal energy extraction with different turbine array configurations, including location, spacing and array size. Preliminary model results suggest that array optimization for tidal energy extraction in a real-world site is a very complex process that requires consideration of multiple factors. Numerical models can be used effectively to assist turbine siting and array arrangement in a tidal turbine farm for tidal energy extraction.

  16. Theoretical Analysis of Amounts of Musical Noise and Speech Distortion in Structure-Generalized Parametric Blind Spatial Subtraction Array

    NASA Astrophysics Data System (ADS)

    Miyazaki, Ryoichi; Saruwatari, Hiroshi; Shikano, Kiyohiro

    We propose a structure-generalized blind spatial subtraction array (BSSA), and the theoretical analysis of the amounts of musical noise and speech distortion. The structure of BSSA should be selected according to the application, i.e., a channelwise BSSA is recommended for listening but a conventional BSSA is suitable for speech recognition.

  17. ANALYSIS OF CHANGES IN GENE EXPRESSION PATTERNS IN FISH EXPOSED TO NATURAL PHARMACEUTICAL AND ENVIRONMENTAL ESTROGENS USING GENE ARRAYS.

    EPA Science Inventory

    Denslow, N.D., P. Larkin, T.L. Sabo-Attwood, J. Kocerha, K.J. Kroll, M.J. Hemmer and L.C. Folmar. 2004. Analysis of Changes in Gene Expression Patterns in Fish Exposed to Natural, Pharmaceutical and Environmental Estrogens Using Gene Arrays (Abstract). Mar. Environ. Res. 58(2-5):...

  18. Membrane filtration of food suspensions.

    PubMed Central

    Sharpe, A N; Peterkin, P I; Dudas, I

    1979-01-01

    Factors affecting the membrane filtration of food suspensions were studied for 58 foods and 13 membrane filters. Lot number within a brand, pore size (0.45 or 0.8 micrometer), and time elapsed before filtration had little effect on filterability. Brand of membrane filter, flow direction, pressure differential, age (microbiological quality) of the food, duration of the blending process, temperature, and concentration of food in the suspension had significant and often predictable effects. Preparation of suspensions by Stomacher (relative to rotary blender) addition of surfactant (particularly at elevated temperature) and prior incubation with proteases sometimes had dramatic effects of filterability. In contrast to popular opinion, foods can be membrane filtered in quantities pertinent to the maximums used in conventional plating procedures. Removal of growth inhibitors and food debris is possible by using membrane filters. Lowering of the limits of detection of microorganisms by concentration on membrane filters can be considered feasible for many foods. The data are particularly relevant to the use of hydrophobic grid-membrane filters (which are capable of enumerating up to 9 X 10(4) organisms per filter) in instrumented methods of food microbiological analysis. Images PMID:760637

  19. Pacific Array

    NASA Astrophysics Data System (ADS)

    Kawakatsu, H.; Takeo, A.; Isse, T.; Nishida, K.; Shiobara, H.; Suetsugu, D.

    2014-12-01

    Based on our recent results on broadband ocean bottom seismometry, we propose a next generation large-scale array experiment in the ocean. Recent advances in ocean bottom broadband seismometry (e.g., Suetsugu & Shiobara, 2014, Annual Review EPS), together with advances in the seismic analysis methodology, have now enabled us to resolve the regional 1-D structure of the entire lithosphere/asthenosphere system, including seismic anisotropy (both radial and azimuthal), with deployments of ~10-15 broadband ocean bottom seismometers (BBOBSs) (namely "ocean-bottom broadband dispersion survey"; Takeo et al., 2013, JGR; Kawakatsu et al., 2013, AGU; Takeo, 2014, Ph.D. Thesis; Takeo et al., 2014, JpGU). Having ~15 BBOBSs as an array unit for 2-year deployment, and repeating such deployments in a leap-frog way (an array of arrays) for a decade or so would enable us to cover a large portion of the Pacific basin. Such efforts, not only by giving regional constraints on the 1-D structure, but also by sharing waveform data for global scale waveform tomography, would drastically increase our knowledge of how plate tectonics works on this planet, as well as how it worked for the past 150 million years. International collaborations might be sought.

  20. Halbach arrays in precision motion control

    SciTech Connect

    Trumper, D.L.; Williams, M.E.

    1995-02-01

    The Halbach array was developed for use as an optical element in particle accelerators. Following up on a suggestion from Klaus Halbach, the authors have investigated the utility of such arrays as the permanent magnet structure for synchronous machines in cartesian, polar, and cylindrical geometries. Their work has focused on the design of a novel Halbach array linear motor for use in a magnetic suspension stage for photolithography. This paper presents the details of the motor design and its force and power characteristics.

  1. The formation of tabular compaction-band arrays: Theoretical and numerical analysis

    NASA Astrophysics Data System (ADS)

    Chemenda, A. I.

    2009-05-01

    The bifurcation analysis of compaction banding is extended to the formation of a tabular discrete compaction-band array. This analysis, taken together with the results of finite-difference simulations, shows that the bifurcation results in the formation of intermittent loading (elastic-plastic) and unloading (elastic) bands. The obtained analytical solution relates the spacing parameter χ (the ratio between the band thickness to the band-to-band distance) to all constitutive and stress-state parameters. Both this solution and numerical models reveal strong dependence of χ on the hardening modulus h: χ increases with h reduction. The band thickness in the numerical models is mesh dependent, but in terms of mesh-zone-size varies only from ˜2 to 4 depending on the constitutive parameters and independently on the mesh resolution. The thickness of the "elementary" compaction bands in real granular materials is equal to a few grain sizes. It follows that one grid zone in the numerical models corresponds approximately to one grain in the real material. The numerical models reproduce both discrete and continuous propagating compaction banding observed in the rock samples. These phenomena were shown to be dependent on the evolution of h and the dilatancy factor with deformation.

  2. Automated image analysis reveals the dynamic 3-dimensional organization of multi-ciliary arrays.

    PubMed

    Galati, Domenico F; Abuin, David S; Tauber, Gabriel A; Pham, Andrew T; Pearson, Chad G

    2015-12-23

    Multi-ciliated cells (MCCs) use polarized fields of undulating cilia (ciliary array) to produce fluid flow that is essential for many biological processes. Cilia are positioned by microtubule scaffolds called basal bodies (BBs) that are arranged within a spatially complex 3-dimensional geometry (3D). Here, we develop a robust and automated computational image analysis routine to quantify 3D BB organization in the ciliate, Tetrahymena thermophila. Using this routine, we generate the first morphologically constrained 3D reconstructions of Tetrahymena cells and elucidate rules that govern the kinetics of MCC organization. We demonstrate the interplay between BB duplication and cell size expansion through the cell cycle. In mutant cells, we identify a potential BB surveillance mechanism that balances large gaps in BB spacing by increasing the frequency of closely spaced BBs in other regions of the cell. Finally, by taking advantage of a mutant predisposed to BB disorganization, we locate the spatial domains that are most prone to disorganization by environmental stimuli. Collectively, our analyses reveal the importance of quantitative image analysis to understand the principles that guide the 3D organization of MCCs.

  3. Flat-plate solar array project. Volume 8: Project analysis and integration

    NASA Technical Reports Server (NTRS)

    Mcguire, P.; Henry, P.

    1986-01-01

    Project Analysis and Integration (PA&I) performed planning and integration activities to support management of the various Flat-Plate Solar Array (FSA) Project R&D activities. Technical and economic goals were established by PA&I for each R&D task within the project to coordinate the thrust toward the National Photovoltaic Program goals. A sophisticated computer modeling capability was developed to assess technical progress toward meeting the economic goals. These models included a manufacturing facility simulation, a photovoltaic power station simulation and a decision aid model incorporating uncertainty. This family of analysis tools was used to track the progress of the technology and to explore the effects of alternative technical paths. Numerous studies conducted by PA&I signaled the achievement of milestones or were the foundation of major FSA project and national program decisions. The most important PA&I activities during the project history are summarized. The PA&I planning function is discussed and how it relates to project direction and important analytical models developed by PA&I for its analytical and assessment activities are reviewed.

  4. Exploring doxorubicin localization in eluting TiO2 nanotube arrays through fluorescence correlation spectroscopy analysis.

    PubMed

    De Santo, Ilaria; Sanguigno, Luigi; Causa, Filippo; Monetta, Tullio; Netti, Paolo A

    2012-11-07

    Drug elution properties of TiO(2) nanotube arrays have been largely investigated by means of solely macroscopic observations. Controversial elution performances have been reported so far and a clear comprehension of these phenomena is still missing as a consequence of a lack of molecular investigation methods. Here we propose a way to discern drug elution properties of nanotubes through the evaluation of drug localization by Fluorescence Correlation Spectroscopy (FCS) analysis. We verified this method upon doxorubicin elution from differently loaded TiO(2) nanotubes. Diverse elution profiles were obtained from nanotubes filled by soaking and wet vacuum impregnation methods. Impregnated nanotubes controlled drug diffusion up to thirty days, while soaked samples completed elution in seven days. FCS analysis of doxorubicin motion in loaded nanotubes clarified that more than 90% of drugs dwell preferentially in inter-nanotube spaces in soaked samples due to decorrelation in a 2D fashion, while a 97% fraction of molecules showed 1D mobility ascribable to displacements along the nanotube vertical axis of wet vacuum impregnated nanotubes. The diverse drug localizations inferred from FCS measurements, together with distinct drug-surface interaction strengths resulting from diverse drug filling techniques, could explain the variability in elution kinetics.

  5. Automated image analysis reveals the dynamic 3-dimensional organization of multi-ciliary arrays

    PubMed Central

    Galati, Domenico F.; Abuin, David S.; Tauber, Gabriel A.; Pham, Andrew T.; Pearson, Chad G.

    2016-01-01

    ABSTRACT Multi-ciliated cells (MCCs) use polarized fields of undulating cilia (ciliary array) to produce fluid flow that is essential for many biological processes. Cilia are positioned by microtubule scaffolds called basal bodies (BBs) that are arranged within a spatially complex 3-dimensional geometry (3D). Here, we develop a robust and automated computational image analysis routine to quantify 3D BB organization in the ciliate, Tetrahymena thermophila. Using this routine, we generate the first morphologically constrained 3D reconstructions of Tetrahymena cells and elucidate rules that govern the kinetics of MCC organization. We demonstrate the interplay between BB duplication and cell size expansion through the cell cycle. In mutant cells, we identify a potential BB surveillance mechanism that balances large gaps in BB spacing by increasing the frequency of closely spaced BBs in other regions of the cell. Finally, by taking advantage of a mutant predisposed to BB disorganization, we locate the spatial domains that are most prone to disorganization by environmental stimuli. Collectively, our analyses reveal the importance of quantitative image analysis to understand the principles that guide the 3D organization of MCCs. PMID:26700722

  6. Droplet Array Platform for High-Resolution Melt Analysis of DNA Methylation Density.

    PubMed

    Athamanolap, Pornpat; Shin, Dong Jin; Wang, Tza-Huei

    2014-06-01

    High-resolution melting (HRM) has garnered significant interest as an analytical technique for a number of applications, including DNA methylation detection, due to its inherent sensitivity and robustness. In this study, we describe a miniaturized assay platform for quantitative methylation density analysis using a microfluidic droplet array cartridge. We demonstrate that the DNA methylation level of the RASSF1A promoter can be directly analyzed using HRM. PCR products were generated by amplifying bisulfite-treated DNA with varying CpG densities using CpG island-flanking primer sets. Subsequent HRM analysis on the miniaturized droplet platform shows distinct melting curve profiles associated with methylation levels, which was verified using a conventional benchtop PCR-HRM system. The characteristic melting temperature (Tm) of the PCR products was used to directly quantify the respective levels of DNA methylation density. Our approach provides a key advantage over current gold standard methods such as methylation-specific PCR (MSP), which are incapable of providing specific information regarding the overall methylation density of the target genes. The miniaturized platform establishes a practical approach to methylation density profiling from multiple DNA samples with a potential application in point-of-care diagnostics.

  7. A colorimetric pH indicators and boronic acids ensemble array for quantitative sugar analysis.

    PubMed

    Ghosh, Krishna Kanta; Yap, Eunice; Kim, Hanjo; Lee, Jun-Seok; Chang, Young-Tae

    2011-04-07

    The colorimetric response patterns of pH indicators and boronic acids ensemble array were used to analyze serial concentrations of mono-, disaccharides quantitatively. Furthermore, this ensemble array was successfully applied to quantify the sugar content in clinically used saline solutions.

  8. Heat dissipation analysis of bendable AlGaInP micro-LED arrays

    NASA Astrophysics Data System (ADS)

    Fang, Shiwei; Wang, Weibiao; Liang, Jingqiu; Liang, Zhongzhu; Qin, Yuxin; Lv, Jinguang

    2017-01-01

    A strategy for fabricating bendable AlGaInP light emitting diode (LED) arrays is presented in this paper. Sample LED arrays with 8 × 8 pixels were fabricated and subjected to bending. Bending only weakly affected the light output power and the current-voltage characteristics of the arrays. LED arrays suffer from a thermal problem owing to the energy loss during the electrical-to-optical energy conversion. We have designed a three-dimensional heat conduction model for analyzing the effect of the polymer substrate, the configuration of pixels, and the micro-structure on heat dissipation in bendable LED arrays. Thermal conductivity of the polymer substrate critically affected the heat dissipation, suggesting that the substrate thickness should be in the 500-1000 μ m range. A larger pixel distance yielded more distributed heat sources and more uniform temperature distribution. Micro-structured polymer substrates yielded lower temperature, especially for the fins array micro-structure. Based on enhancing the polymer's thermal conductivity and distributing LED pixels, optimizing the substrate's micro-structure is an effective method to improve heat dissipation in bendable LED arrays. Optimized heat dissipation could effectively reduce heat accumulation in LED arrays and alleviate an increase in the junction temperature, allowing to increase the output power of the device.

  9. Testing small-aperture array analysis on well-located earthquakes, and application to the location of deep tremor

    USGS Publications Warehouse

    La, Rocca M.; Galluzzo, D.; Malone, S.; McCausland, W.; Saccorotti, G.; Del, Pezzo E.

    2008-01-01

    We have here analyzed local and regional earthquakes using array techniques with the double aim of quantifying the errors associated with the estimation of propagation parameters of seismic signals and testing the suitability of a probabilistic location method for the analysis of nonimpulsive signals. We have applied the zero-lag cross-correlation method to earthquakes recorded by three dense arrays in Puget Sound and Vancouver Island to estimate the slowness and back azimuth of direct P waves and S waves. The results are compared with the slowness and back azimuth computed from the source location obtained by the analysis of data recorded by the Pacific Northwest seismic network (PNSN). This comparison has allowed a quantification of the errors associated with the estimation of slowness and back azimuth obtained through the analysis of array data. The statistical analysis gives ??BP = 10?? and ??BS = 8?? as standard deviations for the back azimuth and ??SP = 0.021 sec/km and ??SS = 0.033 sec /km for the slowness results of the P and S phases, respectively. These values are consistent with the theoretical relationship between slowness and back azimuth and their uncertainties. We have tested a probabilistic source location method on the local earthquakes based on the use of the slowness estimated for two or three arrays without taking into account travel-time information. Then we applied the probabilistic method to the deep, nonvolcanic tremor recorded by the arrays during July 2004. The results of the tremor location using the probabilistic method are in good agreement with those obtained by other techniques. The wide depth range, of between 10 and 70 km, and the source migration with time are evident in our results. The method is useful for locating the source of signals characterized by the absence of pickable seismic phases.

  10. Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis

    NASA Astrophysics Data System (ADS)

    Gao, Wei; Emaminejad, Sam; Nyein, Hnin Yin Yin; Challa, Samyuktha; Chen, Kevin; Peck, Austin; Fahad, Hossain M.; Ota, Hiroki; Shiraki, Hiroshi; Kiriya, Daisuke; Lien, Der-Hsien; Brooks, George A.; Davis, Ronald W.; Javey, Ali

    2016-01-01

    Wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual’s state of health. Sampling human sweat, which is rich in physiological information, could enable non-invasive monitoring. Previously reported sweat-based and other non-invasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanically flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plastic-based sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing. This application could not have been realized using either of these technologies alone owing to their respective inherent limitations. The wearable system is used to measure the detailed sweat profile of human subjects engaged in prolonged indoor and outdoor physical activities, and to make a real-time assessment of the physiological state of the subjects. This platform enables a wide range of personalized diagnostic and physiological monitoring applications.

  11. Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis.

    PubMed

    Gao, Wei; Emaminejad, Sam; Nyein, Hnin Yin Yin; Challa, Samyuktha; Chen, Kevin; Peck, Austin; Fahad, Hossain M; Ota, Hiroki; Shiraki, Hiroshi; Kiriya, Daisuke; Lien, Der-Hsien; Brooks, George A; Davis, Ronald W; Javey, Ali

    2016-01-28

    Wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual's state of health. Sampling human sweat, which is rich in physiological information, could enable non-invasive monitoring. Previously reported sweat-based and other non-invasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanically flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plastic-based sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing. This application could not have been realized using either of these technologies alone owing to their respective inherent limitations. The wearable system is used to measure the detailed sweat profile of human subjects engaged in prolonged indoor and outdoor physical activities, and to make a real-time assessment of the physiological state of the subjects. This platform enables a wide range of personalized diagnostic and physiological monitoring applications.

  12. Field-Programmable Gate Array Computer in Structural Analysis: An Initial Exploration

    NASA Technical Reports Server (NTRS)

    Singleterry, Robert C., Jr.; Sobieszczanski-Sobieski, Jaroslaw; Brown, Samuel

    2002-01-01

    This paper reports on an initial assessment of using a Field-Programmable Gate Array (FPGA) computational device as a new tool for solving structural mechanics problems. A FPGA is an assemblage of binary gates arranged in logical blocks that are interconnected via software in a manner dependent on the algorithm being implemented and can be reprogrammed thousands of times per second. In effect, this creates a computer specialized for the problem that automatically exploits all the potential for parallel computing intrinsic in an algorithm. This inherent parallelism is the most important feature of the FPGA computational environment. It is therefore important that if a problem offers a choice of different solution algorithms, an algorithm of a higher degree of inherent parallelism should be selected. It is found that in structural analysis, an 'analog computer' style of programming, which solves problems by direct simulation of the terms in the governing differential equations, yields a more favorable solution algorithm than current solution methods. This style of programming is facilitated by a 'drag-and-drop' graphic programming language that is supplied with the particular type of FPGA computer reported in this paper. Simple examples in structural dynamics and statics illustrate the solution approach used. The FPGA system also allows linear scalability in computing capability. As the problem grows, the number of FPGA chips can be increased with no loss of computing efficiency due to data flow or algorithmic latency that occurs when a single problem is distributed among many conventional processors that operate in parallel. This initial assessment finds the FPGA hardware and software to be in their infancy in regard to the user conveniences; however, they have enormous potential for shrinking the elapsed time of structural analysis solutions if programmed with algorithms that exhibit inherent parallelism and linear scalability. This potential warrants further

  13. Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis

    PubMed Central

    Nyein, Hnin Yin Yin; Challa, Samyuktha; Chen, Kevin; Peck, Austin; Fahad, Hossain M.; Ota, Hiroki; Shiraki, Hiroshi; Kiriya, Daisuke; Lien, Der-Hsien; Brooks, George A.; Davis, Ronald W.; Javey, Ali

    2016-01-01

    Wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual's state of health1–12. Sampling human sweat, which is rich in physiological information13, could enable non-invasive monitoring. Previously reported sweat-based and other non-invasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state14–18. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanically flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plastic-based sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing. This application could not have been realized using either of these technologies alone owing to their respective inherent limitations. The wearable system is used to measure the detailed sweat profile of human subjects engaged in prolonged indoor and outdoor physical activities, and to make a real-time assessment of the physiological state of the subjects. This platform enables a wide range of personalized diagnostic and physiological monitoring applications. PMID:26819044

  14. Array comparative genomic hybridization and cytogenetic analysis in pediatric acute leukemias.

    PubMed

    Dawson, A J; Yanofsky, R; Vallente, R; Bal, S; Schroedter, I; Liang, L; Mai, S

    2011-10-01

    Most patients with acute lymphocytic leukemia (all) are reported to have acquired chromosomal abnormalities in their leukemic bone marrow cells. Many established chromosome rearrangements have been described, and their associations with specific clinical, biologic, and prognostic features are well defined. However, approximately 30% of pediatric and 50% of adult patients with all do not have cytogenetic abnormalities of clinical significance. Despite significant improvements in outcome for pediatric all, therapy fails in approximately 25% of patients, and these failures often occur unpredictably in patients with a favorable prognosis and "good" cytogenetics at diagnosis.It is well known that karyotype analysis in hematologic malignancies, although genome-wide, is limited because of altered cell kinetics (mitotic rate), a propensity of leukemic blasts to undergo apoptosis in culture, overgrowth by normal cells, and chromosomes of poor quality in the abnormal clone. Array comparative genomic hybridization (acgh-"microarray") has a greatly increased genomic resolution over classical cytogenetics. Cytogenetic microarray, which uses genomic dna, is a powerful tool in the analysis of unbalanced chromosome rearrangements, such as copy number gains and losses, and it is the method of choice when the mitotic index is low and the quality of metaphases is suboptimal. The copy number profile obtained by microarray is often called a "molecular karyotype."In the present study, microarray was applied to 9 retrospective cases of pediatric all either with initial high-risk features or with at least 1 relapse. The conventional karyotype was compared to the "molecular karyotype" to assess abnormalities as interpreted by classical cytogenetics. Not only were previously undetected chromosome losses and gains identified by microarray, but several karyotypes interpreted by classical cytogenetics were shown to be discordant with the microarray results. The complementary use of microarray

  15. Spectral Entropy Based Neuronal Network Synchronization Analysis Based on Microelectrode Array Measurements

    PubMed Central

    Kapucu, Fikret E.; Välkki, Inkeri; Mikkonen, Jarno E.; Leone, Chiara; Lenk, Kerstin; Tanskanen, Jarno M. A.; Hyttinen, Jari A. K.

    2016-01-01

    Synchrony and asynchrony are essential aspects of the functioning of interconnected neuronal cells and networks. New information on neuronal synchronization can be expected to aid in understanding these systems. Synchronization provides insight in the functional connectivity and the spatial distribution of the information processing in the networks. Synchronization is generally studied with time domain analysis of neuronal events, or using direct frequency spectrum analysis, e.g., in specific frequency bands. However, these methods have their pitfalls. Thus, we have previously proposed a method to analyze temporal changes in the complexity of the frequency of signals originating from different network regions. The method is based on the correlation of time varying spectral entropies (SEs). SE assesses the regularity, or complexity, of a time series by quantifying the uniformity of the frequency spectrum distribution. It has been previously employed, e.g., in electroencephalogram analysis. Here, we revisit our correlated spectral entropy method (CorSE), providing evidence of its justification, usability, and benefits. Here, CorSE is assessed with simulations and in vitro microelectrode array (MEA) data. CorSE is first demonstrated with a specifically tailored toy simulation to illustrate how it can identify synchronized populations. To provide a form of validation, the method was tested with simulated data from integrate-and-fire model based computational neuronal networks. To demonstrate the analysis of real data, CorSE was applied on in vitro MEA data measured from rat cortical cell cultures, and the results were compared with three known event based synchronization measures. Finally, we show the usability by tracking the development of networks in dissociated mouse cortical cell cultures. The results show that temporal correlations in frequency spectrum distributions reflect the network relations of neuronal populations. In the simulated data, CorSE unraveled the

  16. Student and school factors associated with school suspension: A multilevel analysis of students in Victoria, Australia and Washington State, United States.

    PubMed

    Sheryl, A Hemphill; Stephanie, M Plenty; Herrenkohl, Todd I; Toumbourou, John W; Catalano, Richard F

    2014-01-01

    One of the common issues schools face is how best to handle challenging student behaviors such as violent behavior, antisocial behavior, bullying, school rule violations, and interrupting other students' learning. School suspension may be used to remove students engaging in challenging behaviors from the school for a period of time. However, the act of suspending students from school may worsen rather than improve their behavior. Research shows that suspensions predict a range of student outcomes, including crime, delinquency, and drug use. It is therefore crucial to understand the factors associated with the use of school suspension, particularly in sites with different policy approaches to problem behaviors. This paper draws on data from state-representative samples of 3,129 Grade 7 and 9 students in Washington State, United States and Victoria, Australia sampled in 2002. Multilevel modeling examined student and school level factors associated with student-reported school suspension. Results showed that both student (being male, previous student antisocial and violent behavior, rebelliousness, academic failure) and school (socioeconomic status of the school, aggregate measures of low school commitment) level factors were associated with school suspension and that the factors related to suspension were similar in the two states. The implications of the findings for effective school behavior management policy are that, rather than focusing only on the student, both student and school level factors need to be addressed to reduce the rates of school suspension.

  17. Student and school factors associated with school suspension: A multilevel analysis of students in Victoria, Australia and Washington State, United States

    PubMed Central

    Sheryl, A. Hemphill; Stephanie, M. Plenty; Herrenkohl, Todd I.; Toumbourou, John W.; Catalano, Richard F.

    2014-01-01

    One of the common issues schools face is how best to handle challenging student behaviors such as violent behavior, antisocial behavior, bullying, school rule violations, and interrupting other students’ learning. School suspension may be used to remove students engaging in challenging behaviors from the school for a period of time. However, the act of suspending students from school may worsen rather than improve their behavior. Research shows that suspensions predict a range of student outcomes, including crime, delinquency, and drug use. It is therefore crucial to understand the factors associated with the use of school suspension, particularly in sites with different policy approaches to problem behaviors. This paper draws on data from state-representative samples of 3,129 Grade 7 and 9 students in Washington State, United States and Victoria, Australia sampled in 2002. Multilevel modeling examined student and school level factors associated with student-reported school suspension. Results showed that both student (being male, previous student antisocial and violent behavior, rebelliousness, academic failure) and school (socioeconomic status of the school, aggregate measures of low school commitment) level factors were associated with school suspension and that the factors related to suspension were similar in the two states. The implications of the findings for effective school behavior management policy are that, rather than focusing only on the student, both student and school level factors need to be addressed to reduce the rates of school suspension. PMID:24860205

  18. Noise analysis for infrared focal plane arrays CMOS readout integrated circuit

    NASA Astrophysics Data System (ADS)

    Lin, Jiamu; Ding, Ruijun; Chen, Honglei; Shen, Xiao; Liu, Fei

    2008-12-01

    With the development of the infrared focal plane detectors, the internal noises in the infrared focal plane arrays (IRFPAs) CMOS readout integrated circuit gradually became an important factor of the development of the IRFPAs. The internal noises in IRFPAs CMOS readout integrated circuit are researched in this work. Part of the motivation for this work is to analyze the mechanism and influence of the internal noises in readout integrated circuit. And according to the signal transporting process, many kinds of internal noises are analyzed. According to the results of theory analysis, it is shown that 1/f noise, KTC noise and pulse switch noise have greater amplitude in frequency domain. These noises have seriously affected the performance of output signal. Also this work has frequency test on the signals of a readout integrated circuit chip which is using DI readout mode. After analyzing the frequency test results, it is shown that 1/f noises and pulse switch noises are the main components of the internal noises in IRFPAS CMOS readout integrated circuit and they are the noises which give a major impact to the output signal. In accordance with the type of noise, some design methods for noise suppression are put forward. And after the simulation of these methods with EDA software, the results show that noises have been reduced. The results of this work gave the referenced gist for improving the noise suppression design of IRFPAs CMOS readout integrated circuit.

  19. Power spectrum analysis of ionospheric fluctuations with the Murchison Widefield Array

    NASA Astrophysics Data System (ADS)

    Loi, Shyeh Tjing; Trott, Cathryn M.; Murphy, Tara; Cairns, Iver H.; Bell, Martin; Hurley-Walker, Natasha; Morgan, John; Lenc, Emil; Offringa, A. R.; Feng, L.; Hancock, P. J.; Kaplan, D. L.; Kudryavtseva, N.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Emrich, D.; Gaensler, B. M.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Johnston-Hollitt, M.; Kasper, J. C.; Kratzenberg, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Ord, S. M.; Prabu, T.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L.

    2015-07-01

    Low-frequency, wide field-of-view (FOV) radio telescopes such as the Murchison Widefield Array (MWA) enable the ionosphere to be sampled at high spatial completeness. We present the results of the first power spectrum analysis of ionospheric fluctuations in MWA data, where we examined the position offsets of radio sources appearing in two data sets. The refractive shifts in the positions of celestial sources are proportional to spatial gradients in the electron column density transverse to the line of sight. These can be used to probe plasma structures and waves in the ionosphere. The regional (10-100 km) scales probed by the MWA, determined by the size of its FOV and the spatial density of radio sources (typically thousands in a single FOV), complement the global (100-1000 km) scales of GPS studies and local (0.01-1 km) scales of radar scattering measurements. Our data exhibit a range of complex structures and waves. Some fluctuations have the characteristics of traveling ionospheric disturbances, while others take the form of narrow, slowly drifting bands aligned along the Earth's magnetic field.

  20. Surface analysis and mechanical behaviour mapping of vertically aligned CNT forest array through nanoindentation

    NASA Astrophysics Data System (ADS)

    Koumoulos, Elias P.; Charitidis, C. A.

    2017-02-01

    Carbon nanotube (CNT) based architectures have increased the scientific interest owning to their exceptional performance rendering them promising candidates for advanced industrial applications in the nanotechnology field. Despite individual CNTs being considered as one of the most known strong materials, much less is known about other CNT forms, such as CNT arrays, in terms of their mechanical performance (integrity). In this work, thermal chemical vapor deposition (CVD) method is employed to produce vertically aligned multiwall (VA-MW) CNT carpets. Their structural properties were studied by means of scanning electron microscopy (SEM), X-Ray diffraction (XRD) and Raman spectroscopy, while their hydrophobic behavior was investigated via contact angle measurements. The resistance to indentation deformation of VA-MWCNT carpets was investigated through nanoindentation technique. The synthesized VA-MWCNTs carpets consisted of well-aligned MWCNTs. Static contact angle measurements were performed with water and glycerol, revealing a rather super-hydrophobic behavior. The structural analysis, hydrophobic behavior and indentation response of VA-MWCNTs carpets synthesized via CVD method are clearly demonstrated. Additionally, cycle indentation load-depth curve was applied and hysteresis loops were observed in the indenter loading-unloading cycle due to the local stress distribution. Hardness (as resistance to applied load) and modulus mapping, at 200 nm of displacement for a grid of 70 μm2 is presented. Through trajection, the resistance is clearly divided in 2 regions, namely the MWCNT probing and the in-between area MWCNT - MWCNT interface.

  1. Multiple Mass Analysis Using an Ion Trap Array (ITA) Mass Analyzer

    NASA Astrophysics Data System (ADS)

    Xiao, Yu; Chu, Yanqiu; Ling, Xing; Ding, Zhengzhi; Xu, Chongsheng; Ding, Li; Ding, Chuan-Fan

    2013-09-01

    A novel ion trap array (ITA) mass analyzer with six ion trapping and analyzing channels was investigated. It is capable of analyzing multiple samples simultaneously. The ITA was built with several planar electrodes made of stainless steel and 12 identical parallel zirconia ceramic substrates plated with conductive metal layers. Each two of the opposing ceramic electrode plates formed a boundary of an ion trap channel and six identical ion trapping and analyzing channels were placed in parallel without physical electrode between any two adjacent channels. The electric field distribution inside each channel was studied with simulation. The new design took the advantage of high precision machining attributable to the rigidity of ceramic, and the convenience of surface patterning technique. The ITA system was tested by using a two-channel electrospray ionization source, a multichannel simultaneous quadruple ion guide, and two detectors. The simultaneous analysis of two different samples with two adjacent ITA channels was achieved and independent mass spectra were obtained. For each channel, the mass resolution was tested. Additional ion trap functions such as mass-selected ion isolation and collision-induced dissociation (CID) were also tested. The results show that one ITA is well suited for multiple simultaneous mass analyses.

  2. Optical sensitivity non-uniformity analysis and optimization of a tilt optical readout focal plane array

    NASA Astrophysics Data System (ADS)

    Fu, Jianyu; Shang, Haiping; Shi, Haitao; Li, Zhigang; Ou, Yi; Chen, Dapeng; Zhang, Qingchuan

    2016-02-01

    An optical readout focal plane array (FPA) usually has a differently tilted reflector/absorber at the initial state due to the micromachining technique. The angular deviation of the reflector/absorber has a strong impact on the optical sensitivity non-uniformity, which is a key factor which affects the imaging uniformity. In this study, a theoretical analysis has been developed, and it is found that the stress matching in SiO2-Aluminum (Al) bilayer leg could make a contribution towards reducing the optical sensitivity non-uniformity. Ion implantation of phosphorus (P) has been utilized to control the stress in SiO2 film. By controlling the implantation energy and dose, the stress and stress stability are modified. The optical readout FPA has been successfully fabricated with the stress-control technique based on P+ implantation. It is demonstrated that the gray response non-uniformity of optical readout FPA has decreased from 25.69% to 10.7%.

  3. Analysis of array illumination generalized by the combination of a binary phase grating and a lens

    NASA Astrophysics Data System (ADS)

    Wang, Huai-sheng

    2007-12-01

    In this paper we propose a method to use a binary phase and a lens to fulfil array illumination. An equation is given to research the array illumination by a given binary phase grating and a lens. We use a lens with the two main excellences. One is that, the lens can raise the intensity of reflected light from a reflective object. Sometime the reflected light is too weak to be recorded. The other is the spatial structure to be conveniently adjusted by the binary phase grating and the lens. Thus industry measurement relevant to array illumination is more easily carried out.

  4. Hybrid superconducting magnetic suspensions

    SciTech Connect

    Tixador, P.; Hiebel, P.; Brunet, Y.

    1996-07-01

    Superconductors, especially high T{sub c} ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms of forces and stiffnesses. The design of the magnet bearing plays an important part. The superconducting magnetic bearing participates less in levitation but must provide a high stabilizing stiffness. This is achieved by the magnet configuration, a good material in term of critical current density and field cooling. A hybrid superconducting suspension for a flywheel is presented. This system consists of a magnet thrust bearing stabilized by superconductors interacting with an alternating polarity magnet structure. First tests and results are reported. Superconducting materials are magnetically melt-textured YBaCuO.

  5. A prototype for the real-time analysis of the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Bulgarelli, Andrea; Fioretti, Valentina; Zoli, Andrea; Aboudan, Alessio; Rodríguez-Vázquez, Juan José; Maier, Gernot; Lyard, Etienne; Bastieri, Denis; Lombardi, Saverio; Tosti, Gino; De Rosa, Adriano; Bergamaschi, Sonia; Interlandi, Matteo; Beneventano, Domenico; Lamanna, Giovanni; Jacquemier, Jean; Kosack, Karl; Antonelli, Lucio Angelo; Boisson, Catherine; Burkowski, Jerzy; Buson, Sara; Carosi, Alessandro; Conforti, Vito; Contreras, Jose Luis; De Cesare, Giovanni; de los Reyes, Raquel; Dumm, Jon; Evans, Phil; Fortson, Lucy; Fuessling, Matthias; Graciani, Ricardo; Gianotti, Fulvio; Grandi, Paola; Hinton, Jim; Humensky, Brian; Knödlseder, Jürgen; Malaguti, Giuseppe; Marisaldi, Martino; Neyroud, Nadine; Nicastro, Luciano; Ohm, Stefan; Osborne, Julian; Rosen, Simon; Tacchini, Alessandro; Torresi, Eleonora; Testa, Vincenzo; Trifoglio, Massimo; Weinstein, Amanda

    2014-07-01

    The Cherenkov Telescope Array (CTA) observatory will be one of the biggest ground-based very-high-energy (VHE) γ- ray observatory. CTA will achieve a factor of 10 improvement in sensitivity from some tens of GeV to beyond 100 TeV with respect to existing telescopes. The CTA observatory will be capable of issuing alerts on variable and transient sources to maximize the scientific return. To capture these phenomena during their evolution and for effective communication to the astrophysical community, speed is crucial. This requires a system with a reliable automated trigger that can issue alerts immediately upon detection of γ-ray flares. This will be accomplished by means of a Real-Time Analysis (RTA) pipeline, a key system of the CTA observatory. The latency and sensitivity requirements of the alarm system impose a challenge because of the anticipated large data rate, between 0.5 and 8 GB/s. As a consequence, substantial efforts toward the optimization of highthroughput computing service are envisioned. For these reasons our working group has started the development of a prototype of the Real-Time Analysis pipeline. The main goals of this prototype are to test: (i) a set of frameworks and design patterns useful for the inter-process communication between software processes running on memory; (ii) the sustainability of the foreseen CTA data rate in terms of data throughput with different hardware (e.g. accelerators) and software configurations, (iii) the reuse of nonreal- time algorithms or how much we need to simplify algorithms to be compliant with CTA requirements, (iv) interface issues between the different CTA systems. In this work we focus on goals (i) and (ii).

  6. Laser-induced breakdown system for colloid characterization in dilute aqueous suspensions

    SciTech Connect

    Brachman, A; Mihardja, S; Palmer, C A; Wruck, D

    1999-08-11

    Detection and sizing of colloids by acoustic detection of laser-induced breakdown and elemental analysis of colloids by laser-induced breakdown spectroscopy are investigated in dilute aqueous suspensions. Development and testing of the methods are performed with standard polystyrene suspensions and prepared suspensions of defined composition and particle size. Application of the methods to analysis of field and laboratory samples is discussed. Am atomic emission lines are observed by laser-induced breakdown spectroscopy of an Am hydroxycarbonate suspension.

  7. Modeling of concentrated suspensions

    NASA Astrophysics Data System (ADS)

    van den Brule, B. H. A. A.; Jongschaap, R. J. J.

    1991-03-01

    The constitutive equation of a concentrated suspension of spherical particles in a Newtonian medium is derived. To this end the method of local volume averaging is employed. To calculate the contribution of the particles to the stress tensor it is assumed that the stress generated in the interstitial holes between the particles is negligible compared to the stress generated in !he narrow gaps separating the particles. The use of the resulting expression is demonstrated with two examples on a cubical arrangement of particles: pure shear and simple shear. Furthermore, the validity of the lubrication approximation employed in this work is checked against the results derived by Nunan and Keller for periodic suspensions.

  8. Bacterial suspensions under flow

    NASA Astrophysics Data System (ADS)

    Clement, Eric; Lindner, Anke; Douarche, Carine; Auradou, Harold

    2016-11-01

    Fluids laden with motile bacteria enter in the category of active matter, a new field currently developing at the convergence of biology, hydrodynamics and statistical physics. Such suspensions were shown recently to exhibit singular macroscopic transport properties. In this paper we review some recent results, either theoretical or experimental, on the active fluid rheology. We focus principally on bacteria suspensions and the objective is to provide the basis for understanding the emergence of the singular constitutive relations characterizing the macroscopic transport properties of such an active fluid under flow.

  9. Magnetic Suspension Technology Workshop

    NASA Technical Reports Server (NTRS)

    Keckler, Claude R. (Editor); Groom, Nelson J. (Editor); Britcher, Colin P. (Editor)

    1993-01-01

    In order to identify the state of magnetic suspension technology in such areas as rotating systems, pointing of experiments or subsystems, payload isolation, and superconducting materials, a workshop on Magnetic Suspension Technology was held at the Langley Research Center in Hampton, Virginia, on 2-4 Feb. 1988. The workshop included five technical sessions in which a total of 24 papers were presented. The technical sessions covered the areas of pointing, isolation, and measurement, rotating systems, modeling and control, and superconductors. A list of attendees is provided.

  10. Fabrication, measurement, and alignment uniformity analysis of linear arrays of optical fibers

    SciTech Connect

    Klingsporn, P.E.

    1997-06-01

    Techniques were developed for assembling a linear array of optical fibers between two silicon plates and polishing the fiber ends in a plane perpendicular to the fiber axis. The silicon plates contained etched V-grooves for capturing the fibers. Optical fibers from two sources were evaluated, along with silicon plates supplied by two sources. Most of the arrays were assembled by epoxy bonding, but some effort was made to form a eutectic bond using gold metallized fibers with gold-coated silicon plates. Measurements were made of the uniformity of spacing of the fiber mode field centers in the linear array. The work was performed to develop a multi-fiber linear array connector to couple optical signals to and from optoelectronic devices.

  11. Analysis of Modified SMI Method for Adaptive Array Weight Control. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Dilsavor, Ronald Louis

    1989-01-01

    An adaptive array is used to receive a desired signal in the presence of weak interference signals which need to be suppressed. A modified sample matrix inversion (SMI) algorithm controls the array weights. The modification leads to increased interference suppression by subtracting a fraction of the noise power from the diagonal elements of the covariance matrix. The modified algorithm maximizes an intuitive power ratio criterion. The expected values and variances of the array weights, output powers, and power ratios as functions of the fraction and the number of snapshots are found and compared to computer simulation and real experimental array performance. Reduced-rank covariance approximations and errors in the estimated covariance are also described.

  12. Finite Element Analysis of Ultrasonic Phased Array Inspections on Anisotropic Welds

    NASA Astrophysics Data System (ADS)

    Harvey, G.; Tweedie, A.; Carpentier, C.; Reynolds, P.

    2011-06-01

    This paper describes a theoretical investigation into the behaviour of anisotropic welds under phased array inspection procedures using a 128 element linear array. Two advanced inspection techniques are simulated, and their suitability compared. A finite element (FE) model, configured in PZFlex, is used to represent both the variations in crystal orientation found in a typical anisotropic weld, and also the linear array configuration. Firstly, through transmission spectra of the weld are used to determine the optimum operating frequency and configuration of the array in order to detect a 3 mm SDH in the weld. Next, the Full Matrix Capture (FMC) technique is simulated, and an image of the weld constructed using the Total Focussing Method (TFM). This is accomplished by transmitting on each element sequentially, while receiving on the remaining 127 elements. This approach provides spatial averaging over the weld area, reducing the distortion caused by the anisotropic media. Finally, Time Reversal Acoustic (TRA) methods were employed to coherently focus the array at the defect and compensate for the elemental timing variations caused by the complex medium. Results illustrate the potential for inspecting anisotropic welds when using correctly designed arrays and implementing novel inspection procedures.

  13. LEO Download Capacity Analysis for a Network of Adaptive Array Ground Stations

    NASA Technical Reports Server (NTRS)

    Ingram, Mary Ann; Barott, William C.; Popovic, Zoya; Rondineau, Sebastien; Langley, John; Romanofsky, Robert; Lee, Richard Q.; Miranda, Felix; Steffes, Paul; Mandl, Dan

    2005-01-01

    To lower costs and reduce latency, a network of adaptive array ground stations, distributed across the United States, is considered for the downlink of a polar-orbiting low earth orbiting (LEO) satellite. Assuming the X-band 105 Mbps transmitter of NASA s Earth Observing 1 (EO-1) satellite with a simple line-of-sight propagation model, the average daily download capacity in bits for a network of adaptive array ground stations is compared to that of a single 11 m dish in Poker Flats, Alaska. Each adaptive array ground station is assumed to have multiple steerable antennas, either mechanically steered dishes or phased arrays that are mechanically steered in azimuth and electronically steered in elevation. Phased array technologies that are being developed for this application are the space-fed lens (SFL) and the reflectarray. Optimization of the different boresight directions of the phased arrays within a ground station is shown to significantly increase capacity; for example, this optimization quadruples the capacity for a ground station with eight SFLs. Several networks comprising only two to three ground stations are shown to meet or exceed the capacity of the big dish, Cutting the data rate by half, which saves modem costs and increases the coverage area of each ground station, is shown to increase the average daily capacity of the network for some configurations.

  14. Bivariate segmentation of SNP-array data for allele-specific copy number analysis in tumour samples

    PubMed Central

    2013-01-01

    Background SNP arrays output two signals that reflect the total genomic copy number (LRR) and the allelic ratio (BAF), which in combination allow the characterisation of allele-specific copy numbers (ASCNs). While methods based on hidden Markov models (HMMs) have been extended from array comparative genomic hybridisation (aCGH) to jointly handle the two signals, only one method based on change-point detection, ASCAT, performs bivariate segmentation. Results In the present work, we introduce a generic framework for bivariate segmentation of SNP array data for ASCN analysis. For the matter, we discuss the characteristics of the typically applied BAF transformation and how they affect segmentation, introduce concepts of multivariate time series analysis that are of concern in this field and discuss the appropriate formulation of the problem. The framework is implemented in a method named CnaStruct, the bivariate form of the structural change model (SCM), which has been successfully applied to transcriptome mapping and aCGH. Conclusions On a comprehensive synthetic dataset, we show that CnaStruct outperforms the segmentation of existing ASCN analysis methods. Furthermore, CnaStruct can be integrated into the workflows of several ASCN analysis tools in order to improve their performance, specially on tumour samples highly contaminated by normal cells. PMID:23497144

  15. Analysis of seismic waves crossing the Santa Clara Valley using the three-component MUSIQUE array algorithm

    NASA Astrophysics Data System (ADS)

    Hobiger, Manuel; Cornou, Cécile; Bard, Pierre-Yves; Le Bihan, Nicolas; Imperatori, Walter

    2016-10-01

    We introduce the MUSIQUE algorithm and apply it to seismic wavefield recordings in California. The algorithm is designed to analyse seismic signals recorded by arrays of three-component seismic sensors. It is based on the MUSIC and the quaternion-MUSIC algorithms. In a first step, the MUSIC algorithm is applied in order to estimate the backazimuth and velocity of incident seismic waves and to discriminate between Love and possible Rayleigh waves. In a second step, the polarization parameters of possible Rayleigh waves are analysed using quaternion-MUSIC, distinguishing retrograde and prograde Rayleigh waves and determining their ellipticity. In this study, we apply the MUSIQUE algorithm to seismic wavefield recordings of the San Jose Dense Seismic Array. This array has been installed in 1999 in the Evergreen Basin, a sedimentary basin in the Eastern Santa Clara Valley. The analysis includes 22 regional earthquakes with epicentres between 40 and 600 km distant from the array and covering different backazimuths with respect to the array. The azimuthal distribution and the energy partition of the different surface wave types are analysed. Love waves dominate the wavefield for the vast majority of the events. For close events in the north, the wavefield is dominated by the first harmonic mode of Love waves, for farther events, the fundamental mode dominates. The energy distribution is different for earthquakes occurring northwest and southeast of the array. In both cases, the waves crossing the array are mostly arriving from the respective hemicycle. However, scattered Love waves arriving from the south can be seen for all earthquakes. Combining the information of all events, it is possible to retrieve the Love wave dispersion curves of the fundamental and the first harmonic mode. The particle motion of the fundamental mode of Rayleigh waves is retrograde and for the first harmonic mode, it is prograde. For both modes, we can also retrieve dispersion and ellipticity

  16. Analysis of condition for uniform lighting generated by array of light emitting diodes with large view angle.

    PubMed

    Qin, Zong; Wang, Kai; Chen, Fei; Luo, Xiaobing; Liu, Sheng

    2010-08-02

    In this research, the condition for uniform lighting generated by array of LEDs with large view angle was studied. The luminous intensity distribution of LED is not monotone decreasing with view angle. A LED with freeform lens was designed as an example for analysis. In a system based on LEDs designed in house with a thickness of 20mm and rectangular arrangement, the condition for uniform lighting was derived and the analytical results demonstrated that the uniformity was not decreasing monotonously with the increasing of LED-to-LED spacing. The illuminance uniformities were calculated with Monte Carlo ray tracing simulations and the uniformity was found to increase with the increasing of certain LED-to-LED spacings anomalously. Another type of large view angle LED and different arrangements were discussed in addition. Both analysis and simulation results showed that the method is available for LED array lighting system design on the basis of large view angle LED..

  17. Keep solids in suspension

    SciTech Connect

    Gladki, H.Z.

    1997-10-01

    Mixing is an important operation in the CPI. It is not synonymous with agitation. Mixing is a random distribution into and through one another of two or more initially separate phases. Within that broad definition is the important specialty area of liquid-solid dispersion. This paper addresses the dispersion of solids in lower concentrations that don`t affect the rheological properties of the fluid. The just suspended condition represents the lowest grade of complete suspension, but this level of agitation is the most efficient for solids-liquid agitation. Higher mixing speeds waste energy. Undersized mixers need replacing. The top-entering mixer has a long history in the CPI and the environmental area. Many suspension studies were run with this type. These papers result in empirical correlations for just suspension conditions to scale up from laboratory measurement. Variables considered are the agitation speed, liquid and solids physical properties, solids concentration, system geometry and impeller type. Lately, submersible mixers are becoming more popular, but there are no published sizing methods. This article will explain how to define the critical hydraulic conditions in the tank to reach just solids suspension for a submersible agitator of the type described here as FJFA (Free Jet Flow Agitator).

  18. Flywheel Magnetic Suspension Developments

    NASA Technical Reports Server (NTRS)

    Palazzolo, Alan; Kenny, Andrew; Sifford, Curtiss; Thomas, Erwin; Bhuiyan, Mohammad; Provenza, Andrew; Kascak, Albert; Montague, Gerald; Lei, Shuliang; Kim, Yeonkyu; Sun, Guangyoung; Chon, ChonHee; Tucker, Randy; Preuss, Jason; Li, Ming; Minihan, Thomas

    2002-01-01

    The paper provides an overview of many areas of the flywheel magnetic suspension (MS) R&D being performed at the Texas A&M Vibration Control and Electromechanics Lab (TAMU-VCEL). This includes system response prediction, actuator optimization and redundancy, controller realizations and stages, sensor enhancements and backup bearing reliability.

  19. Crewbot Suspension Design

    NASA Technical Reports Server (NTRS)

    Wood, Nathan A.

    2005-01-01

    Planetary Surface Robot Work Crews (RWC) represent a new class of construction robots for future deployment in planetary exploration. Rovers currently being used for the RWC platform lack the load carrying capabilities required in regular work. Two new rovers, dubbed CrewBots, being designed in JPL's Planetary Robotics Lab specifically for RWC applications greatly increase the load carrying capabilities of the platform. A major component of the rover design was the design of the rocker type suspension, which increases rover mobility. The design of the suspension for the Crewbots departed from the design of recent rovers. While many previous rovers have used internal bevel gear differentials, the increased load requirements of the Crewbots calls for a more robust system. The solution presented is the use of an external modified three-bar, slider-linkage, rocker-style suspension that increases the moment arm of the differential. The final product is a suspension system capable of supporting the extreme loading cases the RWC platform presents, without consuming a large portion of the Crewbots' internal space.

  20. Alternatives to Student Suspension

    ERIC Educational Resources Information Center

    Robinett, David

    2012-01-01

    Seven years ago, James A. Garfield High School in East Los Angeles set a school record with 613 student suspensions, out of a total enrollment of 5,000 students. The school, made famous by the 1988 film "Stand and Deliver", was no stranger to the high rates of student discipline all too common within the Los Angeles Unified School…

  1. Viscosity of colloidal suspensions

    SciTech Connect

    Cohen, E.G.D.; Schepper, I.M. de

    1995-12-31

    Simple expressions are given for the effective Newtonian viscosity as a function of concentration as well as for the effective visco-elastic response as a function of concentration and imposed frequency, of monodisperse neutral colloidal suspensions over the entire fluid range. The basic physical mechanisms underlying these formulae are discussed. The agreement with existing experiments is very good.

  2. Clustering in Bubble Suspensions

    NASA Astrophysics Data System (ADS)

    Zenit, Roberto

    2000-11-01

    A monidisperse bubble suspension is studied experimentally for the limit in which the Weber number is small and the Reynolds number is large. For this regime the suspension can be modeled using potential flow theory to describe the dynamics of the interstitial fluid. Complete theoretical descriptions have been composed (Spelt and Sangani, 1998) to model the behavior of these suspensions. Bubble clustering is a natural instability that arises from the potential flow considerations, in which bubbles tend to align in horizontal rafts as they move upwards. The appearance of bubble clusters was recently corroborated experimentally by Zenit et al. (2000), who found that although clusters did appear, their strength was not as strong as the predictions. Experiments involving gravity driven shear flows are used to explain the nature of the clustering observed in these type of flows. Balances of the bubble phase pressure (in terms of a calculated diffusion coefficient) and the Maxwell pressure (from the potential flow description) are presented to predict the stability of the bubble suspension. The predictions are compared with experimental results.

  3. COHERENT NETWORK ANALYSIS FOR CONTINUOUS GRAVITATIONAL WAVE SIGNALS IN A PULSAR TIMING ARRAY: PULSAR PHASES AS EXTRINSIC PARAMETERS

    SciTech Connect

    Wang, Yan; Mohanty, Soumya D.; Jenet, Fredrick A.

    2015-12-20

    Supermassive black hole binaries are one of the primary targets of gravitational wave (GW) searches using pulsar timing arrays (PTAs). GW signals from such systems are well represented by parameterized models, allowing the standard Generalized Likelihood Ratio Test (GLRT) to be used for their detection and estimation. However, there is a dichotomy in how the GLRT can be implemented for PTAs: there are two possible ways in which one can split the set of signal parameters for semi-analytical and numerical extremization. The straightforward extension of the method used for continuous signals in ground-based GW searches, where the so-called pulsar phase parameters are maximized numerically, was addressed in an earlier paper. In this paper, we report the first study of the performance of the second approach where the pulsar phases are maximized semi-analytically. This approach is scalable since the number of parameters left over for numerical optimization does not depend on the size of the PTA. Our results show that for the same array size (9 pulsars), the new method performs somewhat worse in parameter estimation, but not in detection, than the previous method where the pulsar phases were maximized numerically. The origin of the performance discrepancy is likely to be in the ill-posedness that is intrinsic to any network analysis method. However, the scalability of the new method allows the ill-posedness to be mitigated by simply adding more pulsars to the array. This is shown explicitly by taking a larger array of pulsars.

  4. Design, Fabrication, and Analysis of a Hybrid FIBER Composite Monoleaf Spring Using Carbon and E-Glass Fibers for Automotive Suspension Applications

    NASA Astrophysics Data System (ADS)

    Sureshkumar, M.; Tamilselvam, P.; Kumaravelan, R.; Dharmalingam, R.

    2014-03-01

    The leaf spring is an important component that provides suspension and plays a vital role in automotive applications. As a vehicle travels, a tremendous force, mostly in terms of a fatigue load, is applied to the leaf spring assembly, particularly to the eye point of the rear axle. In a vehicle with rear-wheel drive, the leaf spring is subject to twisting forces that are opposite in direction and magnitude during the acceleration of drive wheels. A multileaf spring provides an additional strength, but lacks the flexibility and increases the overall weight of the vehicle. Considering the loading conditions, the availability of space in a vehicle, and geometrical considerations, a composite monoleaf spring is designed. In due consideration of the tensile behavior, fatigue resistance, chipping resistance, and base part resistance, a hybrid laminated spring is constructed for the purpose. The present study focuses on an analysis and behavior of a monoleaf spring made of hybrid composite materials, i.e., carbon and E-glass fibers. It is observed that the natural frequency of a hybrid composite leaf spring is twice the frequency of a conventional leaf spring, particularly in the vertical direction, which means that the occurrences of resonance will be less. Also, it is observed that the stress produced in it is lower than that in a conventional leaf spring. The hybrid composite monoleaf spring proved to have better impact and tensile behavior than a steel one.

  5. Uncertainty analysis for trace-moisture standard realized using a magnetic suspension balance/diffusion-tube humidity generator developed at NMIJ

    NASA Astrophysics Data System (ADS)

    Abe, Hisashi; Kitano, Hiroshi; Matsumoto, Nobuhiro; Takahashi, Chiharu

    2015-12-01

    A method of estimating the uncertainty for a primary trace-moisture standard realized using a magnetic suspension balance/diffusion-tube humidity generator (MSB/DTG) developed at the National Metrology Institute of Japan (NMIJ) is reported in full detail. The results of uncertainty analysis showed that the relative expanded uncertainties of the trace-moisture standard with a coverage factor of k = 2 are 6.9 % to 0.75 % for the amount-of-substance fractions (mole fractions) of water in nitrogen in the range of 12 nmol mol-1 to 1400 nmol mol-1. NMIJ participated in an international comparison of primary trace-moisture standards, and the results of the comparison demonstrated that the method of estimating uncertainty developed in this study is reasonable. The dominant uncertainty was attributable to the performance of the trace-moisture analyzer used to evaluate the uncertainty. We conclude that the development of a trace-moisture analyzer based on cavity ring-down spectroscopy with higher performance is needed to reduce the uncertainty of trace-moisture standards based on an MSB/DTG.

  6. Analysis of Molecular Cytogenetic Alteration in Rhabdomyosarcoma by Array Comparative Genomic Hybridization

    PubMed Central

    Liu, Chunxia; Li, Dongliang; Jiang, Jinfang; Hu, Jianming; Zhang, Wei; Chen, Yunzhao; Cui, Xiaobin; Qi, Yan; Zou, Hong; Zhang, WenJie; Li, Feng

    2014-01-01

    Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma with poor prognosis. The genetic etiology of RMS remains largely unclear underlying its development and progression. To reveal novel genes more precisely and new therapeutic targets associated with RMS, we used high-resolution array comparative genomic hybridization (aCGH) to explore tumor-associated copy number variations (CNVs) and genes in RMS. We confirmed several important genes by quantitative real-time polymerase chain reaction (QRT-PCR). We then performed bioinformatics-based functional enrichment analysis for genes located in the genomic regions with CNVs. In addition, we identified miRNAs located in the corresponding amplification and deletion regions and performed miRNA functional enrichment analysis. aCGH analyses revealed that all RMS showed specific gains and losses. The amplification regions were 12q13.12, 12q13.3, and 12q13.3–q14.1. The deletion regions were 1p21.1, 2q14.1, 5q13.2, 9p12, and 9q12. The recurrent regions with gains were 12q13.3, 12q13.3–q14.1, 12q14.1, and 17q25.1. The recurrent regions with losses were 9p12–p11.2, 10q11.21–q11.22, 14q32.33, 16p11.2, and 22q11.1. The mean mRNA level of GLI1 in RMS was 6.61-fold higher than that in controls (p = 0.0477) by QRT-PCR. Meanwhile, the mean mRNA level of GEFT in RMS samples was 3.92-fold higher than that in controls (p = 0.0354). Bioinformatic analysis showed that genes were enriched in functions such as immunoglobulin domain, induction of apoptosis, and defensin. Proto-oncogene functions were involved in alveolar RMS. miRNAs that located in the amplified regions in RMS tend to be enriched in oncogenic activity (miR-24 and miR-27a). In conclusion, this study identified a number of CNVs in RMS and functional analyses showed enrichment for genes and miRNAs located in these CNVs regions. These findings may potentially help the identification of novel biomarkers and/or drug targets implicated in diagnosis of

  7. Whole genome methylation array analysis reveals new aspects in Balkan endemic nephropathy etiology

    PubMed Central

    2013-01-01

    Background Balkan endemic nephropathy (BEN) represents a chronic progressive interstitial nephritis in striking correlation with uroepithelial tumours of the upper urinary tract. The disease has endemic distribution in the Danube river regions in several Balkan countries. DNA methylation is a primary epigenetic modification that is involved in major processes such as cancer, genomic imprinting, gene silencing, etc. The significance of CpG island methylation status in normal development, cell differentiation and gene expression is widely recognized, although still stays poorly understood. Methods We performed whole genome DNA methylation array analysis on DNA pool samples from peripheral blood from 159 affected individuals and 170 healthy individuals. This technique allowed us to determine the methylation status of 27 627 CpG islands throughout the whole genome in healthy controls and BEN patients. Thus we obtained the methylation profile of BEN patients from Bulgarian and Serbian endemic regions. Results Using specifically developed software we compared the methylation profiles of BEN patients and corresponding controls and revealed the differently methylated regions. We then compared the DMRs between all patient-control pairs to determine common changes in the epigenetic profiles. SEC61G, IL17RA, HDAC11 proved to be differently methylated throughout all patient-control pairs. The CpG islands of all 3 genes were hypomethylated compared to controls. This suggests that dysregulation of these genes involved in immunological response could be a common mechanism in BEN pathogenesis in both endemic regions and in both genders. Conclusion Our data propose a new hypothesis that immunologic dysregulation has a place in BEN etiopathogenesis. PMID:24131581

  8. Upper mantle structure of central and West Antarctica from array analysis of Rayleigh wave phase velocities

    NASA Astrophysics Data System (ADS)

    Heeszel, David S.; Wiens, Douglas A.; Anandakrishnan, Sridhar; Aster, Richard C.; Dalziel, Ian W. D.; Huerta, Audrey D.; Nyblade, Andrew A.; Wilson, Terry J.; Winberry, J. Paul

    2016-03-01

    The seismic velocity structure of Antarctica is important, both as a constraint on the tectonic history of the continent and for understanding solid Earth interactions with the ice sheet. We use Rayleigh wave array analysis methods applied to teleseismic data from recent temporary broadband seismograph deployments to image the upper mantle structure of central and West Antarctica. Phase velocity maps are determined using a two-plane wave tomography method and are inverted for shear velocity using a Monte Carlo approach to estimate three-dimensional velocity structure. Results illuminate the structural dichotomy between the East Antarctic Craton and West Antarctica, with West Antarctica showing thinner crust and slower upper mantle velocity. West Antarctica is characterized by a 70-100 km thick lithosphere, underlain by a low-velocity zone to depths of at least 200 km. The slowest anomalies are beneath Ross Island and the Marie Byrd Land dome and are interpreted as upper mantle thermal anomalies possibly due to mantle plumes. The central Transantarctic Mountains are marked by an uppermost mantle slow-velocity anomaly, suggesting that the topography is thermally supported. The presence of thin, higher-velocity lithosphere to depths of about 70 km beneath the West Antarctic Rift System limits estimates of the regionally averaged heat flow to less than 90 mW/m2. The Ellsworth-Whitmore block is underlain by mantle with velocities that are intermediate between those of the West Antarctic Rift System and the East Antarctic Craton. We interpret this province as Precambrian continental lithosphere that has been altered by Phanerozoic tectonic and magmatic activity.

  9. Systematic toxicological analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD).

    PubMed

    Pragst, Fritz; Herzler, Matthias; Erxleben, Björn-Thoralf

    2004-01-01

    In recent years, photodiode array detectors (DADs) have been much improved with respect to wavelength accuracy and resolution, sensitivity, linearity and software operation. UV spectra of drugs measured with up-to-date DADs from different manufacturers are in excellent agreement, have the same quality as measured by a conventional UV spectrometer and are highly reproducible. The calculation of similarity parameters by the DAD software includes the entire range of the spectra compared and allows recognition of very small differences. It was shown in a systematic study of more than 2500 toxicologically relevant substances that UV spectra have a very high specificity with respect to substance structure. Therefore, HPLC-DAD in combination with a comprehensive database of UV spectra and retention parameters is one of the most efficient techniques used in systematic toxicological analysis (STA). Furthermore, the method is advantageous for the identification of metabolites, since in many cases they have the same or very similar UV spectra compared with their respective parent substances and their retention times on reversed-phase columns are shifted in a manner typical of the particular biotransformation reaction. Beside these general aspects, practical applications of HPLC-DAD for STA are reviewed with respect to sample preparation and chromatographic conditions. The efficiency of the method is demonstrated for an example of a routine procedure using liquid-liquid extraction with CH 2 Cl 2 and protein precipitation for sample preparation, a system of three isocratic mobile phases with different acetonitrile/phosphate buffer ratios and RP8 columns for chromatography and a database of 2682 UV spectra and relative retention times for substance identification.

  10. Magnetic arrays

    SciTech Connect

    Trumper, David L.; Kim, Won-jong; Williams, Mark E.

    1997-05-20

    Electromagnet arrays which can provide selected field patterns in either two or three dimensions, and in particular, which can provide single-sided field patterns in two or three dimensions. These features are achieved by providing arrays which have current densities that vary in the windings both parallel to the array and in the direction of array thickness.

  11. Magnetic arrays

    DOEpatents

    Trumper, D.L.; Kim, W.; Williams, M.E.

    1997-05-20

    Electromagnet arrays are disclosed which can provide selected field patterns in either two or three dimensions, and in particular, which can provide single-sided field patterns in two or three dimensions. These features are achieved by providing arrays which have current densities that vary in the windings both parallel to the array and in the direction of array thickness. 12 figs.

  12. High-sensitivity array analysis of gene expression for the early detection of disseminated breast tumor cells in peripheral blood

    PubMed Central

    Martin, Katherine J.; Graner, Edgard; Li, Yi; Price, Laura M.; Kritzman, Brian M.; Fournier, Marcia V.; Rhei, Esther; Pardee, Arthur B.

    2001-01-01

    Early detection is an effective means of reducing cancer mortality. Here, we describe a highly sensitive high-throughput screen that can identify panels of markers for the early detection of solid tumor cells disseminated in peripheral blood. The method is a two-step combination of differential display and high-sensitivity cDNA arrays. In a primary screen, differential display identified 170 candidate marker genes differentially expressed between breast tumor cells and normal breast epithelial cells. In a secondary screen, high-sensitivity arrays assessed expression levels of these genes in 48 blood samples, 22 from healthy volunteers and 26 from breast cancer patients. Cluster analysis identified a group of 12 genes that were elevated in the blood of cancer patients. Permutation analysis of individual genes defined five core genes (P ≤ 0.05, permax test). As a group, the 12 genes generally distinguished accurately between healthy volunteers and patients with breast cancer. Mean expression levels of the 12 genes were elevated in 77% (10 of 13) untreated invasive cancer patients, whereas cluster analysis correctly classified volunteers and patients (P = 0.0022, Fisher's exact test). Quantitative real-time PCR confirmed array results and indicated that the sensitivity of the assay (1:2 × 108 transcripts) was sufficient to detect disseminated solid tumor cells in blood. Expression-based blood assays developed with the screening approach described here have the potential to detect and classify solid tumor cells originating from virtually any primary site in the body. PMID:11226293

  13. Analysis and experimental demonstration of conformal adaptive phase-locked fiber array for laser communications and beam projection applications

    NASA Astrophysics Data System (ADS)

    Liu, Ling

    The primary goal of this research is the analysis, development, and experimental demonstration of an adaptive phase-locked fiber array system for free-space optical communications and laser beam projection applications. To our knowledge, the developed adaptive phase-locked system composed of three fiber collimators (subapertures) with tip-tilt wavefront phase control at each subaperture represents the first reported fiber array system that implements both phase-locking control and adaptive wavefront tip-tilt control capabilities. This research has also resulted in the following innovations: (a) The first experimental demonstration of a phase-locked fiber array with tip-tilt wave-front aberration compensation at each fiber collimator; (b) Development and demonstration of the fastest currently reported stochastic parallel gradient descent (SPGD) system capable of operation at 180,000 iterations per second; (c) The first experimental demonstration of a laser communication link based on a phase-locked fiber array; (d) The first successful experimental demonstration of turbulence and jitter-induced phase distortion compensation in a phase-locked fiber array optical system; (e) The first demonstration of laser beam projection onto an extended target with a randomly rough surface using a conformal adaptive fiber array system. Fiber array optical systems, the subject of this study, can overcome some of the draw-backs of conventional monolithic large-aperture transmitter/receiver optical systems that are usually heavy, bulky, and expensive. The primary experimental challenges in the development of the adaptive phased-locked fiber-array included precise (<5 microrad) alignment of the fiber collimators and development of fast (100kHz-class) phase-locking and wavefront tip-tilt control systems. The precise alignment of the fiber collimator array is achieved through a specially developed initial coarse alignment tool based on high precision piezoelectric picomotors and a

  14. Fast Wavelet Based Functional Models for Transcriptome Analysis with Tiling Arrays

    PubMed Central

    Clement, Lieven; De Beuf, Kristof; Thas, Olivier; Vuylsteke, Marnik; Irizarry, Rafael A.; Crainiceanu, Ciprian M.

    2013-01-01

    For a better understanding of the biology of an organism, a complete description is needed of all regions of the genome that are actively transcribed. Tiling arrays are used for this purpose. They allow for the discovery of novel transcripts and the assessment of differential expression between two or more experimental conditions such as genotype, treatment, tissue, etc. In tiling array literature, many efforts are devoted to transcript discovery, whereas more recent developments also focus on differential expression. To our knowledge, however, no methods for tiling arrays have been described that can simultaneously assess transcript discovery and identify differentially expressed transcripts. In this paper, we adopt wavelet based functional models to the context of tiling arrays. The high dimensionality of the data triggered us to avoid inference based on Bayesian MCMC methods. Instead, we introduce a fast empirical Bayes method that provides adaptive regularization of the functional effects. A simulation study and a case study illustrate that our approach is well suited for the simultaneous assessment of transcript discovery and differential expression in tiling array studies, and that it outperforms methods that accomplish only one of these tasks. PMID:22499683

  15. Analysis of mismatch and shading effects in a photovoltaic array using different technologies

    NASA Astrophysics Data System (ADS)

    Guerrero, J.; Muñoz, Y.; Ibáñez, F.; Ospino, A.

    2014-06-01

    In this paper, we analyze the performance of a photovoltaic array implemented in the Universidad Politécnica de Valencia which consists of modules of different technologies and power, connected in series, in order to quantify the energy losses due to mismatch and the effect of the shadows. To do this, the performance of the modules was measured in operation under ambient conditions with field measurement equipment (AMPROBE Solar Analyzer, Solar - 4000), which allows the extrapolation of measures to standard conditions STC. For the data validation, measures under controlled conditions were taken to some modules in the flash test laboratory of the Institute of Energy Technology ITE of Valencia in Spain. Subsequently the array curves measured were validated with a photovoltaic array model developed in MATLAB-Simulink for the same conditions and technologies. The results of this particular array are lost up to 20% of the energy supplied due to the modules mismatch. The study shows the curves and the energy loss due to shadows modules. This result opens scenarios for conceivable modifications to the PV field configurations today, chosen during the design stage and unchangeable during the operating stage; and gives greater importance to the energy loss by mismatch in the PV array.

  16. Comparative efficiency analysis of fiber-array and conventional beam director systems in volume turbulence.

    PubMed

    Vorontsov, Mikhail; Filimonov, Grigory; Ovchinnikov, Vladimir; Polnau, Ernst; Lachinova, Svetlana; Weyrauch, Thomas; Mangano, Joseph

    2016-05-20

    The performance of two prominent laser beam projection system types is analyzed through wave-optics numerical simulations for various atmospheric turbulence conditions, propagation distances, and adaptive optics (AO) mitigation techniques. Comparisons are made between different configurations of both a conventional beam director (BD) using a monolithic-optics-based Cassegrain telescope and a fiber-array BD that uses an array of densely packed fiber collimators. The BD systems considered have equal input power and aperture diameters. The projected laser beam power inside the Airy size disk at the target plane is used as the performance metric. For the fiber-array system, both incoherent and coherent beam combining regimes are considered. We also present preliminary results of side-by-side atmospheric beam projection experiments over a 7-km propagation path using both the AO-enhanced beam projection system with a Cassegrain telescope and the coherent fiber-array BD composed of 21 densely packed fiber collimators. Both wave-optics numerical simulation and experimental results demonstrate that, for similar system architectures and turbulence conditions, coherent fiber-array systems are more efficient in mitigation of atmospheric turbulence effects and generation of a hit spot of the smallest possible size on a remotely located target.

  17. A comparison between two pneumatic suspension architectures

    NASA Astrophysics Data System (ADS)

    Quaglia, G.; Scopesi, M.; Franco, W.

    2012-04-01

    The aim of this work is to assess and compare the mathematical models of two pneumatic suspension architectures and show how they can converge, after appropriate simplifications, to a general linear form. After making this model dimensionless, it will be used to study, with a transmissibility analysis, the behaviour of a mono-suspension (quarter-car model). Finally, an example of a design process will be shown to highlight the strengths and weaknesses of both architectures and to provide the reader with a practical design tool.

  18. Machines that walk: The adaptive suspension vehicle

    NASA Astrophysics Data System (ADS)

    Song, Shin-Min; Waldron, Kenneth J.

    The design and operation of statically stable fully terrain-adaptive walking machines are discussed, with an emphasis on the adaptive-suspension vehicle developed at Ohio State University (Waldron and McGhee, 1986). Chapters are devoted to a review of walking-machine development, gait analysis and gaits for level walking, gaits for irregular terrain, coordination, leg design by four-bar linkage synthesis, design of a pantograph leg, motion-controlled ankle design, and the Adaptive Suspension Vehicle. Diagrams, drawings, and graphs are provided.

  19. Collodial cluster arrays by electrohydrodynamic printing.

    PubMed

    Korkut, Sibel; Saville, Dudley A; Aksay, Ilhan A

    2008-11-04

    A "stable" electrohydrodynamic jet is used to print arrays of colloidal suspensions on hydrophobic surfaces. Printed lines break up into sessile drops, and capillary forces guide the self-assembly of colloidal particles during the evaporation of the liquid, resulting in arrays of colloidal single particles or particle clusters depending on the concentration of the suspensions. The clusters differ from those formed in the absence of a substrate when the number of particles is larger than three. Multiple structures are found for the same number of particles.

  20. A superconducting large-angle magnetic suspension

    NASA Technical Reports Server (NTRS)

    Downer, James; Goldie, James; Torti, Richard

    1991-01-01

    The component technologies were developed required for an advanced control moment gyro (CMG) type of slewing actuator for large payloads. The key component of the CMG is a large-angle magnetic suspension (LAMS). The LAMS combines the functions of the gimbal structure, torque motors, and rotor bearings of a CMG. The LAMS uses a single superconducting source coil and an array of cryoresistive control coils to produce a specific output torque more than an order of magnitude greater than conventional devices. The designed and tested LAMS system is based around an available superconducting solenoid, an array of twelve room-temperature normal control coils, and a multi-input, multi-output control system. The control laws were demonstrated for stabilizing and controlling the LAMS system.

  1. Quantitative analysis of spherical microbubble cavity array formation in thermally cured polydimethylsiloxane for use in cell sorting applications.

    PubMed

    Giang, Ut-Binh T; Jones, Meghan C; Kaule, Matthew J; Virgile, Chelsea R; Pu, Qihui; Delouise, Lisa A

    2014-02-01

    Microbubbles are spherical cavities formed in thermally cured polydimethylsiloxane (PDMS) using the gas expansion molding technique. Microbubble cavity arrays are generated by casting PDMS over a silicon wafer mold containing arrays of deep etched pits. To be useful in various high throughput cell culture and sorting applications it is imperative that uniform micron-sized cavities can be formed over large areas (in(2)). This paper provides an in-depth quantitative analysis of the fabrication parameters that effect the microbubble cavity formation efficiency and size. These include (1) the hydrophobic coating of the mold, (2) the mold pit dimensions, (3) the spatial arrangement of the pit openings, (4) the curing temperature of PDMS pre-polymer, (5) PDMS thickness, and (6) the presence and composition of residual gas in the PDMS pre-polymer mixture. Results suggest that the principles of heterogeneous nucleation and gas diffusion govern microbubble cavity formation, and that surface tension prevents detachment of the vapor bubble that forms in the PDMS over the pit. Paramerters are defined that enable the fabrication of large format arrays with uniform cavity size over 6 in(2) with a coefficient-of-variation <10 %. The architecture of the microbubble cavity is uniquely advantageous for cell culture. Large format arrays provide a highly versatile system that can be adapted for use in various high-throughput cell sorting applications. Herein, we demonstrate the use of microbubble cavity arrays to dissect the cellular heterogeneity that exists in a tumorigenic cutaneous squamous cell carcinoma cell line at the single cell level.

  2. Stress Analysis and Design of Silicon Solar Cell Arrays and Related Material Properties

    NASA Technical Reports Server (NTRS)

    Salama, A. M.; Rowe, W. M.; Yasui, R. K.

    1972-01-01

    A systematic approach is presented for the design of solar cell arrays to eliminate mechanical failures that might arise in components of the arrays in a thermal environment. A prerequisite to the approach is the characterization of material properties at different temperatures. Significant data is obtained for the thermal behavior of the silicon solar cell material and adhesives. Upon determining the mechanical and thermal material properties of the components of the solar cell array, utilizing a finite element idealization for predicting the stress fields in the components, and employing the von Mises failure criterion, potential failure areas in various design configurations in a given thermal environment are identified. Guide lines and means to optimize a given design are illustrated by two examples.

  3. Quantitative Analysis of Plasma Ablation Using Inverse Wire Array Z-pinches

    SciTech Connect

    Harvey-Thompson, A. J.; Lebedev, S. V.; Bland, S. N.; Chittenden, J. P.; Hall, G. N.; Ning, C.; Suzuki-Vidal, F.; Bott, S. C.

    2009-01-21

    An inverse (exploding) wire array configuration, in which the wires form a cylinder around a current carrying electrode on axis, was used to study the ablation phase of the pinch. This configuration allows the parameters of the plasma from individual wires of the array to be measured as the ablated plasma streams propagate in the outward radial direction. The density distribution and the evolution of the natural mode of modulation of the ablation was measured with interferometry and soft x-ray imaging. Measurements of the voltage across the array, which in this configuration is determined by the private magnetic flux around the individual wires, allows information on the localisation of the current to be obtained.

  4. Modeling and Flight Data Analysis of Spacecraft Dynamics with a Large Solar Array Paddle

    NASA Technical Reports Server (NTRS)

    Iwata, Takanori; Maeda, Ken; Hoshino, Hiroki

    2007-01-01

    The Advanced Land Observing Satellite (ALOS) was launched on January 24 2006 and has been operated successfully since then. This satellite has the attitude dynamics characterized by three large flexible structures, four large moving components, and stringent attitude/pointing stability requirements. In particular, it has one of the largest solar array paddles. Presented in this paper are flight data analyses and modeling of spacecraft attitude motion induced by the large solar array paddle. On orbit attitude dynamics was first characterized and summarized. These characteristic motions associated with the solar array paddle were identified and assessed. These motions are thermally induced motion, the pitch excitation by the paddle drive, and the role excitation. The thermally induced motion and the pitch excitation by the paddle drive were modeled and simulated to verify the mechanics of the motions. The control law updates implemented to mitigate the attitude vibrations are also reported.

  5. CFD Analysis of a Finite Linear Array of Savonius Wind Turbines

    NASA Astrophysics Data System (ADS)

    Belkacem, Belabes; Paraschivoiu, Marius

    2016-09-01

    Vertical axis wind turbines such as Savonius rotors have been shown to be suitable for low wind speeds normally associated with wind resources in all corners of the world. However, the efficiency of the rotor is low. This paper presents results of Computational Fluid Dynamics (CFD) simulations for an array of Savonius rotors that show a significant increase in efficiency. It looks at identifying the effect on the energy yield of a number of turbines placed in a linear array. Results from this investigation suggest that an increase in the energy yield could be achieved which can reach almost two times than the conventional Savonius wind turbine in the case of an array of 11turbines with a distance of 1.4R in between them. The effect of different TSR values and different wind inlet speeds on the farm has been studied for both a synchronous and asynchronous wind farm.

  6. X:Map: annotation and visualization of genome structure for Affymetrix exon array analysis

    PubMed Central

    Yates, Tim; Okoniewski, Michał J.; Miller, Crispin J.

    2008-01-01

    Affymetrix exon arrays aim to target every known and predicted exon in the human, mouse or rat genomes, and have reporters that extend beyond protein coding regions to other areas of the transcribed genome. This combination of increased coverage and precision is important because a substantial proportion of protein coding genes are predicted to be alternatively spliced, and because many non-coding genes are known also to be of biological significance. In order to fully exploit these arrays, it is necessary to associate each reporter on the array with the features of the genome it is targeting, and to relate these to gene and genome structure. X:Map is a genome annotation database that provides this information. Data can be browsed using a novel Google-maps based interface, and analysed and further visualized through an associated BioConductor package. The database can be found at http://xmap.picr.man.ac.uk. PMID:17932061

  7. Adaptive arrays - A new approach to the steady-state analysis

    NASA Technical Reports Server (NTRS)

    Zohar, S.

    1982-01-01

    A closed-form expression for the steady-state output signal-to-noise ratio (SNR) of an n-element adaptive array excited by one desired narrow-band signal and K - 1 narrow-band jammers is obtained. This is facilitated by representing each excitation by a complex n-dimensional vector - the excitation vector. It is shown that the important system parameters are functions of scalar products of pairs of these excitation vectors. In particular, the normalized output SNR of the array is shown to be the ratio of determinants whose elements involve these scaler products. Such determinants are also shown to be involved in the expressions for the optimal array weights.

  8. Space applications of diamagnetic suspensions

    NASA Technical Reports Server (NTRS)

    Pelrine, Ronald E.

    1992-01-01

    Conventional noncontact magnetic suspensions require power and sensor feedback to maintain stability of the levitated object. Magnetic suspensions using superconductors require neither power nor feedback for stability but must be maintained at low temperatures. This paper discusses a little known type of magnetic bearing that does not require power, sensor feedback, or cooling: diamagnetic suspension. While the bearing pressure for diamagnetic suspensions is typically limited to 1 g/sq cm, their simplicity, environmental tolerances, and wide range of material choices suggest that they may be useful for a number of space applications. This paper discusses the fundamentals of diamagnetic suspensions as well as their potential space applications.

  9. Measurements and analysis of optical crosstalk in a microwave kinetic inductance detector array

    NASA Astrophysics Data System (ADS)

    Bisigello, L.; Yates, S. J. C.; Ferrari, L.; Baselmans, J. J. A.; Baryshev, A.

    2016-07-01

    The main advantage of Microwave Kinetic Inductance Detector arrays (MKID) is their multiplexing capability, which allows for building cameras with a large number of pixels and good sensitivity, particularly suitable to perform large blank galaxy surveys. However, to have as many pixels as possible it is necessary to arrange detectors close in readout frequency. Consequently KIDs overlap in frequency and are coupled to each other producing crosstalk. Because crosstalk can be only minimised by improving the array design, in this work we aim to correct for this effect a posteriori. We analysed a MKID array consisting of 880 KIDs with readout frequencies at 4-8 GHz. We measured the beam patterns for every detector in the array and described the response of each detector by using a two-dimensional Gaussian fit. Then, we identified detectors affected by crosstalk above -30 dB level from the maximum and removed the signal of the crosstalking detectors. Moreover, we modelled the crosstalk level for each KID as a function of the readout frequency separation starting from the assumption that the transmission of a KID is a Lorenztian function in power. We were able to describe the general crosstalk level of the array and the crosstalk of each KID within 5 dB, so enabling the design of future arrays with the crosstalk as a design criterion. In this work, we demonstrate that it is possible to process MKID images a posteriori to decrease the crosstalk effect, subtracting the response of each coupled KID from the original map.

  10. Memristor-based programmable logic array (PLA) and analysis as Memristive networks.

    PubMed

    Lee, Kwan-Hee; Lee, Sang-Jin; Kim, Seok-Man; Cho, Kyoungrok

    2013-05-01

    A Memristor theorized by Chua in 1971 has the potential to dramatically influence the way electronic circuits are designed. It is a two terminal device whose resistance state is based on the history of charge flow brought about as the result of the voltage being applied across its terminals and hence can be thought of as a special case of a reconfigurable resistor. Nanoscale devices using dense and regular fabrics such as Memristor cross-bar is promising new architecture for System-on-Chip (SoC) implementations in terms of not only the integration density that the technology can offer but also both improved performance and reduced power dissipation. Memristor has the capacity to switch between high and low resistance states in a cross-bar circuit configuration. The cross-bars are formed from an array of vertical conductive nano-wires cross a second array of horizontal conductive wires. Memristors are realized at the intersection of the two wires in the array through appropriate processing technology such that any particular wire in the vertical array can be connected to a wire in the horizontal array by switching the resistance of a particular intersection to a low state while other cross-points remain in a high resistance state. However the approach introduces a number of challenges. The lack of voltage gain prevents logic being cascaded and voltage level degradation affects robustness of the operation. Moreover the cross-bars introduce sneak current paths when two or more cross points are connected through the switched Memristor. In this paper, we propose Memristor-based programmable logic array (PLA) architecture and develop an analytical model to analyze the logic level on the memristive networks. The proposed PLA architecture has 12 inputs maximum and can be cascaded for more input variables with R(off)/R(on) ratio in the range from 55 to 160 of Memristors.

  11. Room acoustics analysis using circular arrays: an experimental study based on sound field plane-wave decomposition.

    PubMed

    Torres, Ana M; Lopez, Jose J; Pueo, Basilio; Cobos, Maximo

    2013-04-01

    Plane-wave decomposition (PWD) methods using microphone arrays have been shown to be a very useful tool within the applied acoustics community for their multiple applications in room acoustics analysis and synthesis. While many theoretical aspects of PWD have been previously addressed in the literature, the practical advantages of the PWD method to assess the acoustic behavior of real rooms have been barely explored so far. In this paper, the PWD method is employed to analyze the sound field inside a selected set of real rooms having a well-defined purpose. To this end, a circular microphone array is used to capture and process a number of impulse responses at different spatial positions, providing angle-dependent data for both direct and reflected wavefronts. The detection of reflected plane waves is performed by means of image processing techniques applied over the raw array response data and over the PWD data, showing the usefulness of image-processing-based methods for room acoustics analysis.

  12. Network analysis provides insights into evolution of 5S rDNA arrays in Triticum and Aegilops.

    PubMed Central

    Allaby, R G; Brown, T A

    2001-01-01

    We have used network analysis to study gene sequences of the Triticum and Aegilops 5S rDNA arrays, as well as the spacers of the 5S-DNA-A1 and 5S-DNA-2 loci. Network analysis describes relationships between 5S rDNA sequences in a more realistic fashion than conventional tree building because it makes fewer assumptions about the direction of evolution, the extent of sexual isolation, and the pattern of ancestry and descent. The networks show that the 5S rDNA sequences of Triticum and Aegilops species are related in a reticulate manner around principal nodal sequences. The spacer networks have multiple principal nodes of considerable antiquity but the gene network has just one principal node, corresponding to the correct gene sequence. The networks enable orthologous groups of spacer sequences to be identified. When orthologs are compared it is seen that the patterns of intra- and interspecific diversity are similar for both genes and spacers. We propose that 5S rDNA arrays combine sequence conservation with a large store of mutant variations, the number of correct gene copies within an array being the result of neutral processes that act on gene and spacer regions together. PMID:11238418

  13. C3N4 Nanosheet Modified Microwell Array with Enhanced Electrochemiluminescence for Total Analysis of Cholesterol at Single Cells.

    PubMed

    Xu, Jingjing; Jiang, Depeng; Qin, Yanling; Xia, Juan; Jiang, Dechen; Chen, Hong-Yuan

    2017-02-21

    Here, a g-C3N4 nanosheet modified microwell array providing enhanced electrochemiluminescence (ECL) and better visible sensitivity was prepared to simultaneously analyze total (membrane and intracellular) cholesterol at single cells. The detection limit for ECL visualization of hydrogen peroxide at microwell array was improved to be 500 nM that guaranteed the detection of low concentration cholesterol at single cells in parallel. To achieve single cell cholesterol analysis, the individual cells cultured at the microwell array were exposed to cholesterol oxidase generating hydrogen peroxide for luminescence analysis of membrane cholesterol, and then treated with triton X-100, cholesterol esterase, and cholesterol oxidase to produce hydrogen peroxide from intracellular cholesterol for luminescence determination. The observation of the luminescence spots at microwells in these two steps confirmed the codetection of membrane and intracellular cholesterol at single cells. The inhibition of intracellular acyl-coA/cholesterol acyltransferase (ACAT) resulted in less intracellular cholesterol storage (less luminescence) and more membrane cholesterol (more luminescence). The correlation of the luminescence intensity with the amount of cholesterol confirmed that our assay could simultaneously monitor membrane and intracellular cholesterol pools at different cellular states, which should offer more information for the study of cholesterol-related pathways at single cells.

  14. Spheroid arrays for high-throughput single-cell analysis of spatial patterns and biomarker expression in 3D

    PubMed Central

    Ivanov, Delyan P.; Grabowska, Anna M.

    2017-01-01

    We describe and share a device, methodology and image analysis algorithms, which allow up to 66 spheroids to be arranged into a gel-based array directly from a culture plate for downstream processing and analysis. Compared to processing individual samples, the technique uses 11-fold less reagents, saves time and enables automated imaging. To illustrate the power of the technology, we showcase applications of the methodology for investigating 3D spheroid morphology and marker expression and for in vitro safety and efficacy screens. First, spheroid arrays of 11 cell-lines were rapidly assessed for differences in spheroid morphology. Second, highly-positive (SOX-2), moderately-positive (Ki-67) and weakly-positive (βIII-tubulin) protein targets were detected and quantified. Third, the arrays enabled screening of ten media compositions for inducing differentiation in human neurospheres. Last, the application of spheroid microarrays for spheroid-based drug screens was demonstrated by quantifying the dose-dependent drop in proliferation and increase in differentiation in etoposide-treated neurospheres. PMID:28134245

  15. Analysis and performance evaluation of an all-fiber wide range interrogation system for a Bragg grating sensor array

    NASA Astrophysics Data System (ADS)

    Rajan, Ginu; Semenova, Yuliya; Farrell, Gerald

    2009-05-01

    Analysis and performance evaluation of a macro-bend fiber based interrogation system for a Bragg grating sensor array is presented. Due to the characteristic properties of the macro-bend fiber filter such as polarization and temperature dependence and the total noise associated with the ratiometric system, a best fit ratio slope is required to interrogate multiple fiber Bragg gratings (FBGs) whose peak wavelengths are spread over a wide wavelength range, rather than the optimal slope for individual FBGs. In this study, we have used an FBG array with 5 FBGs with peak reflected wavelengths lying between 1525 and 1575 nm. The analysis of the system is carried out and a fiber filter with a slope which covers a wavelength range of 1525-1575 nm is selected which ensures a resolution and accuracy for all the FBG sensors in the array as close as possible to that which would be achieved with a filter with an optimal slope for each FBG. Performance evaluation of the system is carried out and the static strain, dynamic strain, and temperature are measured with the developed interrogation system.

  16. Analysis of O-glycans as 9-fluorenylmethyl derivatives and its application to the studies on glycan array.

    PubMed

    Yamada, Keita; Hirabayashi, Jun; Kakehi, Kazuaki

    2013-03-19

    A method is proposed for the analysis of O-glycans as 9-fluorenylmethyl (Fmoc) derivatives. After releasing the O-glycans from the protein backbone in the presence of ammonia-based media, the glycosylamines thus formed are conveniently labeled with Fmoc-Cl and analyzed by HPLC and MALDI-TOF MS after easy purification. Fmoc labeled O-glycans showed 3.5 times higher sensitivities than those labeled with 2-aminobenzoic acid in fluorescent detection. Various types of O-glycans having sialic acids, fucose, and/or sulfate residues were successfully labeled with Fmoc and analyzed by HPLC and MALDI-TOF MS. The method was applied to the comprehensive analysis of O-glycans expressed on MKN45 cells (human gastric adenocarcinoma). In addition, Fmoc-derivatized O-glycans were easily converted to free hemiacetal or glycosylamine-form glycans that are available for fabrication of glycan array and neoglycoproteins. To demonstrate the availability of our methods, we fabricate the glycan array with Fmoc labeled glycans derived from mucin samples and cancer cells. The model studies using the glycan array showed clear interactions between immobilized glycans and some lectins.

  17. Optical position measurement for a Large Gap Magnetic Suspension System

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.; Shelton, Kevin J.; Clemmons, James I.

    1991-01-01

    This paper describes the design of an optical position measurement system which is being built as part of the NASA Langley Large Gap Magnetic Suspension System (LGMSS). The LGMSS is a five degree-of-freedom, large-gap magnetic suspension system which is being built for Langley Research Center as part of the Advanced Controls Test Facility (ACTF). The LGMSS consists of a planar array of electromagnets which levitate and position a cylindrically shaped model containing a permanent magnet core. The optical position measurement system provides information on the location and orientation of the model to the LGMSS control system to stabilize levitation of the model.

  18. Association between chromosomal aberration of COX8C and tethered spinal cord syndrome: array-based comparative genomic hybridization analysis

    PubMed Central

    Zhao, Qiu-jiong; Bai, Shao-cong; Cheng, Cheng; Tao, Ben-zhang; Wang, Le-kai; Liang, Shuang; Yin, Ling; Hang, Xing-yi; Shang, Ai-jia

    2016-01-01

    Copy number variations have been found in patients with neural tube abnormalities. In this study, we performed genome-wide screening using high-resolution array-based comparative genomic hybridization in three children with tethered spinal cord syndrome and two healthy parents. Of eight copy number variations, four were non-polymorphic. These non-polymorphic copy number variations were associated with Angelman and Prader-Willi syndromes, and microcephaly. Gene function enrichment analysis revealed that COX8C, a gene associated with metabolic disorders of the nervous system, was located in the copy number variation region of Patient 1. Our results indicate that array-based comparative genomic hybridization can be used to diagnose tethered spinal cord syndrome. Our results may help determine the pathogenesis of tethered spinal cord syndrome and prevent occurrence of this disease. PMID:27651783

  19. Photomixing of chlamydomonas rheinhardtii suspensions

    NASA Astrophysics Data System (ADS)

    Dervaux, Julien; Capellazzi Resta, Marina; Abou, Bérengère; Brunet, Philippe

    2014-11-01

    Chlamydomonas rheinhardtii is a fast swimming unicellular alga able to bias its swimming direction in gradients of light intensity, an ability know as phototaxis. We have investigated experimentally both the swimming behavior of individual cells and the macroscopic response of shallow suspensions of these micro-organisms in response to a localized light source. At low light intensity, algae exhibit positive phototaxis and accumulate beneath the excitation light. In weakly concentrated thin layers, the balance between phototaxis and cell motility results in steady symmetrical patterns compatible with a purely diffusive model using effective diffusion coefficients extracted from the analysis of individual cell trajectories. However, at higher cell density and layer depth, collective effects induce convective flows around the light source. These flows disturb the cell concentration patterns which spread and may then becomes unstable. Using large passive tracer particles, we have characterized the velocity fields associated with this forced bioconvection and their dependence on the cell density and layer depth. By tuning the light distribution, this mechanism of photo-bioconvection allows a fine control over the local fluid flows, and thus the mixing efficiency, in algal suspensions.

  20. Migrational Instabilities in Particle Suspensions

    NASA Technical Reports Server (NTRS)

    Goddard, Joe D.

    1996-01-01

    This work deals with an instability arising from the shear-induced migration of particles in dense suspensions coupled with a dependence of viscosity on particle concentration. The analysis summarized here treats the inertialess (Re = O) linear stability of homogeneous simple shear flows for a Stokesian suspension model of the type proposed by Leighton and Acrivos (1987). Depending on the importance of shear-induced migration relative to concentration-driven diffusion, this model admits short-wave instability arising from wave-vector stretching by the base flow and evolving into particle-depleted shear bands. Moreover, this instability in the time-dependent problem corresponds to loss of ellipticity in the associated static problem (Re = O, Pe = O). While the isotropic version of the Leighton-Acrivos model is found to be stable with their experimentally determined parameters for simple shear, it is known that the stable model does not give a good quantitative description of particle clustering in the core of pipe flow (Nott and Brady 1994). This leads to the conjecture that an appropriate variant on the above model could explain such clustering as a two-phase bifurcation in the base flow.

  1. Design and analysis of a large cylinder antenna array in Tianlai

    NASA Astrophysics Data System (ADS)

    Chen, Z. P.; Wang, R. L.; Peterson, J.; Chen, X. L.; Zhang, J. Y.; Shi, H. L.

    2016-07-01

    In order to make a large area survey, detect a large scale structure and understand dark energy, a large radio interference array with a large number of feeds is required. However, cost and deformation control are main considerations in designing a large antenna array. In this paper we designed a cylinder parabolic structure for antenna array 45m x 40m of "Tianlai" project in Xinjiang, China in 2015. In order to largely reduce weight and cost, the antenna was divided into many assemble units, their structure was optimized by MSC.Patran/Nastran and their reflector deformation under various load cases of gravity, snow and wind was analyzed. For the feed support, we compared different types of structure such as arch-bridge, tower, cable and pole, and by mechanical simulations we found that the arch-bridge structure is very helpful to achieve large span, decrease weight and improve stability, for example, the total weight of optimized structure can be reduced to 43.7% of before. Finally some deformation measurement and experiment methods were discussed, which can be extended to array 100m×100m in the future.

  2. Accuracy and Resolution Analysis of a Direct Resistive Sensor Array to FPGA Interface.

    PubMed

    Oballe-Peinado, Óscar; Vidal-Verdú, Fernando; Sánchez-Durán, José A; Castellanos-Ramos, Julián; Hidalgo-López, José A

    2016-02-01

    Resistive sensor arrays are formed by a large number of individual sensors which are distributed in different ways. This paper proposes a direct connection between an FPGA and a resistive array distributed in M rows and N columns, without the need of analog-to-digital converters to obtain resistance values in the sensor and where the conditioning circuit is reduced to the use of a capacitor in each of the columns of the matrix. The circuit allows parallel measurements of the N resistors which form each of the rows of the array, eliminating the resistive crosstalk which is typical of these circuits. This is achieved by an addressing technique which does not require external elements to the FPGA. Although the typical resistive crosstalk between resistors which are measured simultaneously is eliminated, other elements that have an impact on the measurement of discharge times appear in the proposed architecture and, therefore, affect the uncertainty in resistance value measurements; these elements need to be studied. Finally, the performance of different calibration techniques is assessed experimentally on a discrete resistor array, obtaining for a new model of calibration, a maximum relative error of 0.066% in a range of resistor values which correspond to a tactile sensor.

  3. Matlab software for the analysis of seismic waves recorded by three-element arrays

    NASA Astrophysics Data System (ADS)

    Pignatelli, A.; Giuntini, A.; Console, R.

    2008-07-01

    We develop and implement an algorithm for inverting three-element array data on a Matlab platform. The algorithm allows reliable estimation of back azimuth and apparent velocity from seismic records under low signal-to-noise conditions. We start with a cubic spline interpolation of the waveforms and determine the differences between arrival times at pairs of array elements. The time differences are directly computed from cross-correlation functions. The advantages of this technique are (a) manual picking of the onset of each arrival is not necessary at each array element; (b) interpolation makes it possible to estimate time differences at a higher resolution than the sampling rate of the digital waveforms; (c) consistency among three independent determinations provides a reliability check; and (d) the value of apparent velocity indicates the nature of the recorded wavelet and physically checks the results. The algorithm was tested on data collected by a tri-partite array (with an aperture of ˜250 m) deployed in 1998 by the National Data Center of Israel, during a field experiment in southern Israel, 20 km southwest of the Dead Sea. The data include shallow explosions and natural earthquakes under both high and low signal-to-noise conditions. The procedure developed in this study is considered suitable for searching of small aftershocks subsequent to an underground explosion, in the context of on-site inspections according to the Comprehensive Nuclear-Test-Ban Treaty (CTBT).

  4. Analysis of phytoestrogens and polyphenols in plasma, tissue, and urine using HPLC with coulometric array detection.

    PubMed

    Gamache, P H; Acworth, I N

    1998-03-01

    The study of phytoestrogens in food sources and their metabolism, effects, and mechanism of action in animals requires very selective and often sensitive analytical techniques. We have applied coulometric array detection, which uses a series of flow-through electrochemical sensors each providing 100% electrolytic efficiency, for measurement of a variety of phytochemicals in complex matrices. Recent work has involved the resolution of coumestrol (COM), daidzein (DE), daidzin (DI), diethylstilbestrol (DES), enterodiol (ED), enterolactone (EL), equol (EQ), estradiol (E2), estriol (E3), estrone (E), genistein (GE), and quercetin (QE). Binary gradient reversed-phase (C18) chromatography was used with a sodium acetate buffer (pH 4.8)-methanol-acetonitrile solvent system. Eight coulometric sensors were set at 260, 320, 380, 440, 500, 560, 620, and 680 mV (vs Pd reference). Compounds were resolved in 30 min via both their oxidation/reduction characteristics and chromatographic behavior. Respective maximal oxidation potentials (mV) were: COM = 380; DE = 500; DI = 620; DES = 440; ED = 620; EL = 620; EQ = 560; E2 = 560; E3 = 560; E1 = 560; GE = 500; and QE = 260 with limits of detection of 5-50 pg. Uterine tissue homogenates (30 mg/ml in Tris-EDTA) and plasma from Sprague-Dawley rats sacrificed 1 hr after sc injection with either vehicle, dimethylsulfoxide, 10 microg DES, or 1.0 mg EQ were analyzed before and after enzymatic hydrolysis with beta-glucuronidase/sulfatase. Urine samples from humans receiving a Boston-area diet with or without soy protein isolate supplements were also analyzed. Ethanol extracts were evaporated and reconstituted in 20% methanol before HPLC analysis. DE, ED, EL, EQ, and GE were determined in urine with less than 5% (R.S.D.) intraassay imprecision and 85%-102% recovery. Levels (ng/ml) of GE (1.8), QE (11.2), and EQ (1.7) were found in control plasma before hydrolysis and GE (293), QE (183), and EQ (22) after hydrolysis. Higher concentrations

  5. Cosmic Infrared Background Fluctuations in Deep Spitzer Infrared Array Camera Images: Data Processing and Analysis

    NASA Technical Reports Server (NTRS)

    Arendt, Richard; Kashlinsky, A.; Moseley, S.; Mather, J.

    2010-01-01

    This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer Infrared Array Camera observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations that would otherwise corrupt the results. The procedures and results for masking bright sources and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large-scale ([greater, similar]30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power-law components. We discuss the relationship between fluctuations measured at different wavelengths and depths, and the relations between constraints on the mean intensity of the CIB and its fluctuation spectrum. Consistent with growing evidence that the [approx]1-5 [mu]m mean intensity of the CIB may not be as far above the integrated emission of resolved galaxies as has been reported in some analyses of DIRBE and IRTS observations, our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low ([greater, similar]1 nW m-2 sr-1 at 3-5 [mu]m), and thus consistent with current [gamma]-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs

  6. Articulated Suspension Without Springs

    NASA Technical Reports Server (NTRS)

    Bickler, Donald B.

    1990-01-01

    Wheels negotiate bumps and holes with minimal tilting of vehicle body. In new suspension, wheel climbs obstacle as high as 1 1/2 times its diameter without excessive tilting of chassis. Provides highly stable ride over rough ground for such vehicles as wheelchairs, military scout cars, and police and fire robots. System of levers distributes weight to wheels. Sized to distribute equal or other desired portions of load among wheels.

  7. Analysis of traveling-wave electro-osmotic pumping with double-sided electrode arrays

    NASA Astrophysics Data System (ADS)

    Yeh, Hung-Chun; Yang, Ruey-Jen; Luo, Win-Jet

    2011-05-01

    In this paper, a series of numerical simulations was performed to investigate the pumping performance of electro-osmotic micropumps containing electrode arrays patterned on the upper and lower sides of a microchannel. The simulations have been analyzed with a linear electro-osmotic model based upon the Debye-Hückel theory of the double layer. The potential drop across the diffuse layer is assumed to be less than 25 mV (kBT/e), and there is a linear response between the surface charge and the voltage drop across the double layer. The double layer is not resolved but is lumped into effective parameters that are imported from the Debye-Hückel and Stern layers. We examined the effects of the relative positioning of the electrodes in the opposing arrays (i.e., symmetrical or staggered), and the phase lag and the angular frequency of the alternating current (ac) signals applied to the electrodes within the two arrays. A critical height of the microchannel was observed, below which the interactions of the applied electrical potentials on the walls became significant. The optimum pumping effect was obtained when the electrode arrays were symmetrical to one another around the centerline of the channel and were activated by ac potentials with a 0° phase shift. The corresponding angular frequency of the maximum pumping velocity for different phase shifts of the applied ac signals was also determined. Overall, the simulation results presented in this paper provide a useful insight into the optimal design parameters and operating conditions for micropumps containing two arrays of microelectrodes on the microchannel walls.

  8. Analysis of traveling-wave electro-osmotic pumping with double-sided electrode arrays.

    PubMed

    Yeh, Hung-Chun; Yang, Ruey-Jen; Luo, Win-Jet

    2011-05-01

    In this paper, a series of numerical simulations was performed to investigate the pumping performance of electro-osmotic micropumps containing electrode arrays patterned on the upper and lower sides of a microchannel. The simulations have been analyzed with a linear electro-osmotic model based upon the Debye-Hückel theory of the double layer. The potential drop across the diffuse layer is assumed to be less than 25 mV (k(B)T/e), and there is a linear response between the surface charge and the voltage drop across the double layer. The double layer is not resolved but is lumped into effective parameters that are imported from the Debye-Hückel and Stern layers. We examined the effects of the relative positioning of the electrodes in the opposing arrays (i.e., symmetrical or staggered), and the phase lag and the angular frequency of the alternating current (ac) signals applied to the electrodes within the two arrays. A critical height of the microchannel was observed, below which the interactions of the applied electrical potentials on the walls became significant. The optimum pumping effect was obtained when the electrode arrays were symmetrical to one another around the centerline of the channel and were activated by ac potentials with a 0° phase shift. The corresponding angular frequency of the maximum pumping velocity for different phase shifts of the applied ac signals was also determined. Overall, the simulation results presented in this paper provide a useful insight into the optimal design parameters and operating conditions for micropumps containing two arrays of microelectrodes on the microchannel walls.

  9. Dense Suspension Splash

    NASA Astrophysics Data System (ADS)

    Zhang, Wendy; Dodge, Kevin M.; Peters, Ivo R.; Ellowitz, Jake; Klein Schaarsberg, Martin H.; Jaeger, Heinrich M.

    2014-03-01

    Upon impact onto a solid surface at several meters-per-second, a dense suspension plug splashes by ejecting liquid-coated particles. We study the mechanism for splash formation using experiments and a numerical model. In the model, the dense suspension is idealized as a collection of cohesionless, rigid grains with finite surface roughness. The grains also experience lubrication drag as they approach, collide inelastically and rebound away from each other. Simulations using this model reproduce the measured momentum distribution of ejected particles. They also provide direct evidence supporting the conclusion from earlier experiments that inelastic collisions, rather than viscous drag, dominate when the suspension contains macroscopic particles immersed in a low-viscosity solvent such as water. Finally, the simulations reveal two distinct routes for splash formation: a particle can be ejected by a single high momentum-change collision. More surprisingly, a succession of small momentum-change collisions can accumulate to eject a particle outwards. Supported by NSF through its MRSEC program (DMR-0820054) and fluid dynamics program (CBET-1336489).

  10. Stress in dilute suspensions

    NASA Technical Reports Server (NTRS)

    Passman, Stephen L.

    1989-01-01

    Generally, two types of theory are used to describe the field equations for suspensions. The so-called postulated equations are based on the kinetic theory of mixtures, which logically should give reasonable equations for solutions. The basis for the use of such theory for suspensions is tenuous, though it at least gives a logical path for mathematical arguments. It has the disadvantage that it leads to a system of equations which is underdetermined, in a sense that can be made precise. On the other hand, the so-called averaging theory starts with a determined system, but the very process of averaging renders the resulting system underdetermined. A third type of theory is proposed in which the kinetic theory of gases is used to motivate continuum equations for the suspended particles. This entails an interpretation of the stress in the particles that is different from the usual one. Classical theory is used to describe the motion of the suspending medium. The result is a determined system for a dilute suspension. Extension of the theory to more concentrated systems is discussed.

  11. The Tail Suspension Test

    PubMed Central

    Terrillion, Chantelle E.; Piantadosi, Sean C.; Bhat, Shambhu; Gould, Todd D.

    2012-01-01

    The tail-suspension test is a mouse behavioral test useful in the screening of potential antidepressant drugs, and assessing of other manipulations that are expected to affect depression related behaviors. Mice are suspended by their tails with tape, in such a position that it cannot escape or hold on to nearby surfaces. During this test, typically six minutes in duration, the resulting escape oriented behaviors are quantified. The tail-suspension test is a valuable tool in drug discovery for high-throughput screening of prospective antidepressant compounds. Here, we describe the details required for implementation of this test with additional emphasis on potential problems that may occur and how to avoid them. We also offer a solution to the tail climbing behavior, a common problem that renders this test useless in some mouse strains, such as the widely used C57BL/6. Specifically, we prevent tail climbing behaviors by passing mouse tails through a small plastic cylinder prior to suspension. Finally, we detail how to manually score the behaviors that are manifested in this test. PMID:22315011

  12. Multiplexed Analysis of Serum Breast and Ovarian Cancer Markers by Means of Suspension Bead-quantum Dot Microarrays

    NASA Astrophysics Data System (ADS)

    Brazhnik, Kristina; Sokolova, Zinaida; Baryshnikova, Maria; Bilan, Regina; Nabiev, Igor; Sukhanova, Alyona

    Multiplexed analysis of cancer markers is crucial for early tumor diagnosis and screening. We have designed lab-on-a-bead microarray for quantitative detection of three breast cancer markers in human serum. Quantum dots were used as bead-bound fluorescent tags for identifying each marker by means of flow cytometry. Antigen-specific beads reliably detected CA 15-3, CEA, and CA 125 in serum samples, providing clear discrimination between the samples with respect to the antigen levels. The novel microarray is advantageous over the routine single-analyte ones due to the simultaneous detection of various markers. Therefore the developed microarray is a promising tool for serum tumor marker profiling.

  13. Solar array deployment mechanism

    NASA Technical Reports Server (NTRS)

    Calassa, Mark C.; Kackley, Russell

    1995-01-01

    This paper describes a Solar Array Deployment Mechanism (SADM) used to deploy a rigid solar array panel on a commercial spacecraft. The application required a deployment mechanism design that was not only lightweight, but also could be produced and installed at the lowest possible cost. This paper covers design, test, and analysis of a mechanism that meets these requirements.

  14. Effect of osmotic pressure to bioimpedance indexes of erythrocyte suspensions

    NASA Astrophysics Data System (ADS)

    Melnikov, A. A.; Nikolaev, D. V.; Malahov, M. V.; Smirnov, A. V.

    2012-12-01

    In the paper we studied effects of osmotic modification of red blood cells on bioimpedance parameters of erythrocyte suspension. The Cole parameters: the extracellular (Re) and intracellular (Ri) fluid resistance, the Alpha parameter, the characteristic frequency (Fchar) and the cell membranes capacitance (Cm) of concentrated erythrocyte suspensions were measured by bioimpedance analyser in the frequency range 5 - 500 kHz. Erythrocytes were incubated in hypo-, hyper- and isoosmotic solutions to achieve changes in cell volume. It was found that Re and Alpha increased in the suspensions with low osmolarity and decreased in the hypertonic suspensions. Ri, Fchar and Cm were higher in the hyperosmotic and were lower in the hypoosmotic suspensions. Correlations of all BIS parameters with MCV were obtained, but multiple regression analysis showed that only Alpha parameter was independently related to MCV (β=0.77, p=0.01). Thus Alpha parameter may be related the mean corpuscular volume of cells.

  15. ENCODE Tiling Array Analysis Identifies Differentially Expressed Annotated and Novel 5′ Capped RNAs in Hepatitis C Infected Liver

    PubMed Central

    Maxwell, Christopher I.; Nelson, Cassie A.; Schwartz, Jason J.; Nix, David A.; Hagedorn, Curt H.

    2011-01-01

    Microarray studies of chronic hepatitis C infection have provided valuable information regarding the host response to viral infection. However, recent studies of the human transcriptome indicate pervasive transcription in previously unannotated regions of the genome and that many RNA transcripts have short or lack 3′ poly(A) ends. We hypothesized that using ENCODE tiling arrays (1% of the genome) in combination with affinity purifying Pol II RNAs by their unique 5′ m7GpppN cap would identify previously undescribed annotated and unannotated genes that are differentially expressed in liver during hepatitis C virus (HCV) infection. Both 5′-capped and poly(A)+ populations of RNA were analyzed using ENCODE tiling arrays. Sixty-four annotated genes were significantly increased in HCV cirrhotic as compared to control liver; twenty-seven (42%) of these genes were identified only by analyzing 5′ capped RNA. Thirty-one annotated genes were significantly decreased; sixteen (50%) of these were identified only by analyzing 5′ capped RNA. Bioinformatic analysis showed that capped RNA produced more consistent results, provided a more extensive expression profile of intronic regions and identified upregulated Pol II transcriptionally active regions in unannotated areas of the genome in HCV cirrhotic liver. Two of these regions were verified by PCR and RACE analysis. qPCR analysis of liver biopsy specimens demonstrated that these unannotated transcripts, as well as IRF1, TRIM22 and MET, were also upregulated in hepatitis C with mild inflammation and no fibrosis. The analysis of 5′ capped RNA in combination with ENCODE tiling arrays provides additional gene expression information and identifies novel upregulated Pol II transcripts not previously described in HCV infected liver. This approach, particularly when combined with new RNA sequencing technologies, should also be useful in further defining Pol II transcripts differentially regulated in specific disease states and

  16. Kokkos Array

    SciTech Connect

    Edwards Daniel Sunderland, Harold Carter

    2012-09-12

    The Kokkos Array library implements shared-memory array data structures and parallel task dispatch interfaces for data-parallel computational kernels that are performance-portable to multicore-CPU and manycore-accelerator (e.g., GPGPU) devices.

  17. Theoretical and experimental analysis of the sedimentation kinetics of concentrated red cell suspensions in a centrifugal field: determination of the aggregation and deformation of RBC by flux density and viscosity functions.

    PubMed

    Lerche, D; Frömer, D

    2001-01-01

    detail the rheological behavior of suspended rigid spheres at low Reynolds numbers ranging from 10(-6) to 10(-3). The method here introduced also enabled us to investigate RBC suspensions with respect to the deformability and interactions of the cells by means of the separation analysis. Normal, rigid as well as aggregating RBC exhibited marked differences in the sedimentation kinetics, which were quantified by means of the flux and viscosity functions based on the theory of kinematic waves.

  18. Finite Element Analysis and Failure Mode Characterization of Pyramidal Fin Arrays Produced by Masked Cold Gas Dynamic Spray

    NASA Astrophysics Data System (ADS)

    Cormier, Yannick; Dupuis, Philippe; Jodoin, Bertrand; Ghaei, Abbas

    2015-12-01

    This work evaluates the shear strength of pyramidal fin arrays made from various feedstock materials (cylindrical aluminum, spherical nickel, and cylindrical stainless steel 304 powders) deposited on an Al6061-T6 substrate. Higher shear strength was measured for the nickel fin array followed by the stainless steel 304 and the aluminum arrays. Different failure modes were observed by inspecting the fracture surfaces under Scanning Electron Microscope. Deposition between the cold sprayed nickel and stainless fins was detected whereas dimples were noticed on the substrate between the fins when aluminum is used as the feedstock material. A numerical simulation of normal and angled impacts using the high strain rate Preston-Tonks-Wallace model was carried out in order to have a better understanding of the experimental results. The equivalent plastic strain (PEEQ) obtained from the finite element analysis at normal impact correlates with the different shear strengths measured experimentally. Furthermore, even if a higher PEEQ was observed for angled impacts compared to its normal collision counterpart, it is suggested that the particles may not bond because of the rotational restitution momentum caused by the tangential friction generated during angled impacts. This rotational restitution momentum was not detected for particle impacts normal to the substrate surface.

  19. Nanocylinder arrays

    DOEpatents

    Tuominen, Mark; Schotter, Joerg; Thurn-Albrecht, Thomas; Russell, Thomas P.

    2007-03-13

    Pathways to rapid and reliable fabrication of nanocylinder arrays are provided. Simple methods are described for the production of well-ordered arrays of nanopores, nanowires, and other materials. This is accomplished by orienting copolymer films and removing a component from the film to produce nanopores, that in turn, can be filled with materials to produce the arrays. The resulting arrays can be used to produce nanoscale media, devices, and systems.

  20. Nanocylinder arrays

    DOEpatents

    Tuominen, Mark; Schotter, Joerg; Thurn-Albrecht, Thomas; Russell, Thomas P.

    2009-08-11

    Pathways to rapid and reliable fabrication of nanocylinder arrays are provided. Simple methods are described for the production of well-ordered arrays of nanopores, nanowires, and other materials. This is accomplished by orienting copolymer films and removing a component from the film to produce nanopores, that in turn, can be filled with materials to produce the arrays. The resulting arrays can be used to produce nanoscale media, devices, and systems.

  1. Analysis of upper and lower bounds of the frame noise in linear detector arrays

    NASA Technical Reports Server (NTRS)

    Jaggi, S.

    1991-01-01

    This paper estimates the upper and lower bounds of the frame noise of a linear detector array that uses a one-dimensional scan pattern. Using chi-square distribution, it is analytically shown why it is necessary to use the average of the variances and not the average of the standard deviations to estimate these bounds. Also, a criteria for determining whether any excessively noisy lines exist among the detectors is derived from these bounds. Using a Gaussian standard random variable generator, these bounds are demonstrated to be accurate within the specified confidence interval. A silicon detector array is then used for actual dark current measurements. The criterion developed for determination of noisy detectors is checked on the experimentally obtained data.

  2. Grating lobes analysis based on blazed grating theory for liquid crystal optical-phased array

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Cui, Guolong; Kong, Lingjiang; Xiao, Feng; Liu, Xin; Zhang, Xiaoguang

    2013-09-01

    The grating lobes of the liquid crystal optical-phased array (LCOPA) based on blazed grating theory is studied. Using the Fraunhofer propagation principle, the analytical expressions of the far-field intensity distribution are derived. Subsequently, we can obtain both the locations and the intensities of the grating lobes. The derived analytical functions that provide an insight into single-slit diffraction and multislit interference effect on the grating lobes are discussed. Utilizing the conventional microwave-phased array technique, the intensities of the grating lobes and the main lobe are almost the same. Different from this, the derived analytical functions demonstrate that the intensities of the grating lobes are less than that of the main lobe. The computer simulations and experiments show that the proposed method can correctly estimate the locations and the intensities of the grating lobes for a LCOPA simultaneously.

  3. Systems Analysis of EGF Receptor Signaling Dynamics with Micro-Western Arrays

    PubMed Central

    Ciaccio, Mark F.; Wagner, Joel P.; Chuu, Chih-Pin; Lauffenburger, Douglas A.; Jones, Richard B.

    2010-01-01

    We describe micro-western arrays, which enable quantitative, sensitive and high-throughput assessment of protein abundance and modifications following electrophoretic separation of micro-arrayed cell lysates. This method allowed us to measure 91 phosphosites on 67 proteins at six time points following stimulation with five EGF concentrations in A431 human carcinoma cells. We inferred the connectivities among 15 phosphorylation sites across 10 receptor tyrosine kinases (RTK) and 2 sites from Src kinase using Bayesian network modeling and two mutual information-based methods; the three inference methods yielded significant agreement on the network topology. These results imply multiple distinct RTK coactivation mechanisms and support the notion that small amounts of experimental data collected from phenotypically diverse network states may enable network inference. PMID:20101245

  4. Application of an array processor to the analysis of magnetic data for the Doublet III tokamak

    SciTech Connect

    Wang, T.S.; Saito, M.T.

    1980-08-01

    Discussed herein is a fast computational technique employing the Floating Point Systems AP-190L array processor to analyze magnetic data for the Doublet III tokamak, a fusion research device. Interpretation of the experimental data requires the repeated solution of a free-boundary nonlinear partial differential equation, which describes the magnetohydrodynamic (MHD) equilibrium of the plasma. For this particular application, we have found that the array processor is only 1.4 and 3.5 times slower than the CDC-7600 and CRAY computers, respectively. The overhead on the host DEC-10 computer was kept to a minimum by chaining the complete Poisson solver and free-boundary algorithm into one single-load module using the vector function chainer (VFC). A simple time-sharing scheme for using the MHD code is also discussed.

  5. Ultra-high throughput rotary capillary array electrophoresis scanner for fluorescent DNA sequencing and analysis.

    PubMed

    Scherer, J R; Kheterpal, I; Radhakrishnan, A; Ja, W W; Mathies, R A

    1999-06-01

    We have constructed a rotary confocal fluorescence scanner and capillary array electrophoresis system that is designed to analyze over 1000 DNA sequencing or fragment sizing separations in parallel. Capillaries are arranged around the surface of a cylinder and a rotating objective in the middle of the cylinder excites and collects fluorescence from labeled DNA fragments as they pass the capillary detection window. The capillaries are pressure-filled with a replaceable matrix and the samples are electrokinetically injected in parallel from a stainless steel microtiter plate at the cathode end. We demonstrate that the instrument is capable of producing four-color data from all capillaries at a scan rate of 4 Hz (corresponding to a linear scan velocity of 121 cm/s). M13 sequencing data were obtained using a 128 capillary array mounted in half of the first quadrant of the scanner. In this initial run, read lengths greater than 500 bases were obtained in over 60% of the capillaries.

  6. Real Time Imaging Analysis Using a Terahertz Quantum Cascade Laser and a Microbolometer Focal Plane Array

    DTIC Science & Technology

    2008-12-01

    sensing area, assuming that the device remains approximately in thermodynamic equilibrium, the heat balance equation can be expressed as o d TP G T C...11. Modulated radiation incident on focal plane array. .........................................17 Figure 12. Temperature change in a pixel for P0...for b) 4.3 and c) 4.9 THz windows. HITRAN (solid line) and FTIR results (dashed line). Lasing spectra of QCL’s are depicted with dashed vertical

  7. Experimental design, analysis of variance and slide quality assessment in gene expression arrays.

    PubMed

    Draghici, S; Kuklin, A; Hoff, B; Shams, S

    2001-05-01

    A microarray experiment is a sequence of complicated molecular biology procedures relying on various laboratory tools, instrumentation and experimenter's skills. This paper discusses statistical models for distinguishing small changes in gene expression from the noise in the system. It describes methods for assigning statistical confidence to gene expression values derived from a single array slide. Some of the theory is discussed in the context of practical applications via software usage.

  8. Analysis of Analog Photonic Links Employing Multiple-Channel (Arrayed) Receivers

    DTIC Science & Technology

    2008-11-07

    with an optical amplifier to boost the received optical signal level. While analog links utilizing single-channel and balanced receivers have been...utilizing single-channel and balanced receivers have been thoroughly analyzed, arrayed receiver architec- tures have received far less attention. In...output optical modulators and balanced -detection [8, 9] are frequently employed. This technique has been utilized alone to achieve the first multi

  9. Theoretical and experimental comparative analysis of beamforming methods for loudspeaker arrays under given performance constraints

    NASA Astrophysics Data System (ADS)

    Olivieri, Ferdinando; Fazi, Filippo Maria; Nelson, Philip A.; Shin, Mincheol; Fontana, Simone; Yue, Lang

    2016-07-01

    Methods for beamforming are available that provide the signals used to drive an array of sources for the implementation of systems for the so-called personal audio. In this work, performance of the delay-and-sum (DAS) method and of three widely used methods for optimal beamforming are compared by means of computer simulations and experiments in an anechoic environment using a linear array of sources with given constraints on quality of the reproduced field at the listener's position and limit to input energy to the array. Using the DAS method as a benchmark for performance, the frequency domain responses of the loudspeaker filters can be characterized in three regions. In the first region, at low frequencies, input signals designed with the optimal methods are identical and provide higher directivity performance than that of the DAS. In the second region, performance of the optimal methods are similar to the DAS method. The third region starts above the limit due to spatial aliasing. A method is presented to estimate the boundaries of these regions.

  10. Fabrication and analysis of microfiber array platform for optogenetics with cellular resolution

    PubMed Central

    Chen, Jian-Hong; Chou, Ming-Yi; Pan, Chien-Yuan; Wang, Lon A.

    2016-01-01

    Optogenetics has emerged as a revolutionary technology especially for neuroscience and has advanced continuously over the past decade. Conventional approaches for patterned in vivo optical illumination have a limitation on the implanted device size and achievable spatio-temporal resolution. In this work, we developed a fabrication process for a microfiber array platform. Arrayed poly(methyl methacrylate) (PMMA) microfibers were drawn from a polymer solution and packaged with polydimethylsiloxane (PDMS). The exposed end face of a packaged microfiber was tuned to have a size corresponding to a single cell. To demonstrate its capability for single cell optogenetics, HEK293T cells expressing channelrhodopsin-2 (ChR2) were cultured on the platform and excited with UV laser. We could then observe an elevation in the intracellular Ca2+ concentrations due to the influx of Ca2+ through the activated ChR2 into the cytosol. The statistical and simulation results indicate that the proposed microfiber array platform can be used for single cell optogenetic applications. PMID:27895984

  11. Simulation Analysis on Photoelectric Conversion Characteristics of Silicon Nanowire Array Photoelectrodes.

    PubMed

    Zhao, Yong; Yu, Jin; Fang, Li-Guang; Zheng, Jun; Wang, Hui-Qin; Yuan, Ji-Ren; Wu, Shaolong; Cheng, Guo-An

    2015-12-01

    Semiconductor nanowire photoelectrochemical cells have attracted extensive attention in the light-conversion field owing to the low-cost preparation, excellent optical absorption, and short distance of carrier collection. Although there are numbers of experimental investigations to improve the device performance, the understanding of the detailed process of photoelectric conversion needs to be further improved. In this work, a thorough optoelectronic simulation is employed to figure out how the nanowire diameter, doping concentration, and illumination wavelength affect the photoelectric conversion characteristics of the silicon nanowire array photoelectrodes. We find that two balances should be carefully weighted between optical absorption and photogenerated-carrier collection, along with between short-circuit photocurrent density and open-circuit voltage. For the small-diameter nanowire array photoelectrodes, the overall absorption is higher than that of the larger-diameter ones with the most contribution from the nanowires. However, the substrate shows increasing absorption with increasing illumination wavelength. Higher doping density leads to a larger open-circuit voltage; while lower doping density can guarantee a relatively higher short-circuit photocurrent. To obtain high-light-conversion-efficiency photoelectrodes, the doping density should be carefully chosen with considerations of illumination wavelength and surface recombination. Suppressing the surface recombination velocity can effectively enhance the short-circuit photocurrent (open-circuit voltage) for the lightly (heavily) doped nanowire array photoelectrodes. Our systematical results provide a theoretical guidance for the photoelectrochemical devices based on semiconductor nanostructures.

  12. Performance bounds for passive sensor arrays operating in a turbulent medium: Plane-wave analysis

    NASA Astrophysics Data System (ADS)

    Collier, S. L.; Wilson, D. K.

    2003-05-01

    The performance bounds of a passive acoustic array operating in a turbulent medium with fluctuations described by a von Kármán spectrum are investigated. This treatment considers a single, monochromatic, plane-wave source at near-normal incidence. A line-of-sight propagation path is assumed. The primary interests are in calculating the Cramer-Rao lower bounds of the azimuthal and elevational angles of arrival and in observing how these bounds change with the introduction of additional unknowns, such as the propagation distance, turbulence parameters, and signal-to-noise ratio. In both two and three dimensions, it is found that for large values of the index-of-refraction variance, the Cramer-Rao lower bounds of the angles of arrival increase significantly at large values of the normalized propagation distance. For small values of the index-of-refraction variance and normalized propagation distance, the signal-to-noise ratio is found to be the limiting factor. In the two-dimensional treatment, it is found that the estimate of the angle of arrival will decouple from the estimates of the other parameters with the appropriate choice of array geometry. In three dimensions, again with an appropriate choice of array geometry, the estimates of the azimuth and elevation will decouple from the estimates of the other parameters, but due to the constraints of the model, will remain coupled to one another.

  13. Novel oral suspensions: a review.

    PubMed

    Kathpalia, Harsha; Phadke, Chetan

    2014-01-01

    An oral pharmaceutical suspension has been one of the most favorable dosage forms for pediatric and geriatric patients or patients unable to tolerate solid dosage forms. The liquid form is preferred because of the ease of swallowing and flexibility in the administration of doses. This emerging area of suspensions as applied to the pharmaceutical field are discussed in the current article enlightening the vision of the readers towards pharmaceutical formulations including nanosuspensions, non-aqueous suspensions and modified release suspensions. The emphasis in the article focuses on the essential principles involved in the process of formation of different types of suspensions and their applications, since novel oral suspensions have potential to provide various strategy systems.

  14. A Digital Control Algorithm for Magnetic Suspension Systems

    NASA Technical Reports Server (NTRS)

    Britton, Thomas C.

    1996-01-01

    An ongoing program exists to investigate and develop magnetic suspension technologies and modelling techniques at NASA Langley Research Center. Presently, there is a laboratory-scale large air-gap suspension system capable of five degree-of-freedom (DOF) control that is operational and a six DOF system that is under development. Those systems levitate a cylindrical element containing a permanent magnet core above a planar array of electromagnets, which are used for levitation and control purposes. In order to evaluate various control approaches with those systems, the Generic Real-Time State-Space Controller (GRTSSC) software package was developed. That control software package allows the user to implement multiple control methods and allows for varied input/output commands. The development of the control algorithm is presented. The desired functionality of the software is discussed, including the ability to inject noise on sensor inputs and/or actuator outputs. Various limitations, common issues, and trade-offs are discussed including data format precision; the drawbacks of using either Direct Memory Access (DMA), interrupts, or program control techniques for data acquisition; and platform dependent concerns related to the portability of the software, such as memory addressing formats. Efforts to minimize overall controller loop-rate and a comparison of achievable controller sample rates are discussed. The implementation of a modular code structure is presented. The format for the controller input data file and the noise information file is presented. Controller input vector information is available for post-processing by mathematical analysis software such as MATLAB1.

  15. Statistical analysis of spatial and temporal variations in atmospheric electric fields from a regional array of field mills

    NASA Astrophysics Data System (ADS)

    Lucas, G. M.; Thayer, J. P.; Deierling, W.

    2017-01-01

    Electric fields and currents of the global electric circuit have been measured at different locations and time periods around the globe, but a long-term analysis from a regional array of electric field mills has never been performed. Kennedy Space Center (KSC) in Florida has an array of over 30 electric field mills that have been continuously operating and archiving data for over 18 years. KSC is also instrumented with many meteorological towers. With this initial statistical analysis of a long-term data set four unique observations are reported that encompass global as well as local effects. To quantitatively describe the effects, a model to determine near-surface electric fields, incorporating space charge, and conductivity perturbations is developed. Statistical autonomous grouping of the mills using the spatial array demonstrates a greater than 50 V/m spatial variation from coastal to inland mills caused by wind-advected space charge generated near the coast. A temporal analysis identified a strong, globally generated, diurnal signature, but only a weak annual signal is found. A realistic limit on conductivity reductions within clouds is estimated by analyzing overhead cloud cover in relation to near-surface electric field strengths. The estimated in-cloud conductivity reduction of approximately 1/3 is similar to observations but appreciably less than values estimated from microphysical cloud estimates. Finally, an enhancement in the electric field at sunrise is statistically well correlated with low wind speeds and high relative humidities. This paper provides a statistical description of local environmental effects on near-surface electric fields by which to base future studies.

  16. Analysis of copy number variations in Mexican Holstein cattle using axiom genome-wide Bos 1 array

    PubMed Central

    Salomon-Torres, Ricardo; Villa-Angulo, Rafael; Villa-Angulo, Carlos

    2015-01-01

    Recently, for copy number variation (CNV) analysis, bovine researchers have focused mainly on the use of genome-wide SNP genotyping arrays. One of the highest densities commercially available SNPchips for cattle is the Affymetrix axiom genome-wide Bos 1, which assays 648,315 informative SNPs across the whole bovine genome. Here, we describe the microarray data, quality controls and validation implemented in a study published in Genetics and Molecular Research Journal in 2015 [1]. The microarray raw data has been deposited into Gene Expression Omnibus under accession #GSE54813. PMID:26981375

  17. Transfer-printing of single DNA molecule arrays on graphene for high resolution electron imaging and analysis

    PubMed Central

    Cerf, Aline; Alava, Thomas; Barton, Robert A.; Craighead, Harold G.

    2011-01-01

    Graphene represents the ultimate substrate for high-resolution transmission electron microscopy, but the deposition of biological samples on this highly hydrophobic material has until now been a challenge. We present a reliable method for depositing ordered arrays of individual elongated DNA molecules on single-layer graphene substrates for high resolution electron beam imaging and electron energy loss spectroscopy analysis. This method is a necessary step towards the observation of single elongated DNA molecules with single base spatial resolution to directly read genetic and epigenetic information. PMID:21919532

  18. RP-HPLC analysis of phenolic compounds and flavonoids in beverages and plant extracts using a CoulArray detector.

    PubMed

    Jandera, Pavel; Skeifíková, Veronika; Rehová, Lucie; Hájek, Tomás; Baldriánová, Lucie; Skopová, Gabriela; Kellner, Vladimír; Horna, Ales

    2005-06-01

    Methods were developed for the analysis of natural antioxidants including phenolic compounds and flavonoids in beverages and plant extracts using gradient HPLC with multi-channel electrochemical coulometric detection. Suitability of various reversed-phase columns for this purpose was compared; pH and mobile phase gradients were optimized with respect to the separation selectivity and sensitivity of detection. Because of different target compounds in various sample types, the overlapping resolution maps and the normalized resolution product approaches described earlier were used to select optimum columns and gradients to suit the analysis of the individual sample types. The methods were applied to the analysis of phenolic compounds and flavonoids in beer, wine, tea, and yacon extracts. 32 phenolic compounds were identified and determined, including derivatives of benzoic and cinnamic acids, flavones, and a few related glycosides. Eight-channel CoulArray detection offers high selectivity and sensitivity with limits of detection in the low microg L(-1) range, at least an order of magnitude lower than single-channel coulometric detection using the Coulochem detector. No special sample pretreatment is necessary and, because of the compatibility of the CoulArray detector with gradient elution, phenolic antioxidants of different polarities can be determined in a single run. In addition to the retention times, the ratios of the areas of the pre-dominant and post-dominant peaks to the area of the dominant peak can be used for improved identification of natural antioxidants.

  19. Array-based analysis of secreted glycoproteins for rapid selection of a single cell producing a glycoprotein with desired glycosylation.

    PubMed

    Park, Sunyoung; Kim, Wanjung; Kim, Yongtae; Son, Young Dok; Lee, Sang-Chul; Kim, Eunkyung; Kim, Sung Ho; Kim, Jung Hoe; Kim, Hak-Sung

    2010-07-01

    The therapeutic efficacy and in vivo biological function of a glycoprotein is significantly affected by its glycosylation profile. For the development of glycoproteins with therapeutic applications, selection of cell lines producing a glycoprotein with adequate glycoform is crucial. Here, we demonstrate an array-based analysis of secreted glycoproteins for rapid and efficient selection of a single cell producing a glycoprotein with desirable glycosylation. Our approach relies on microengraving and interrogation of glycoproteins produced by individual cells in a microwell array in terms of glycosylation profile as well as the produced amount. On the basis of statistical analysis of the interrogation, single cells which are predicted to produce a desired glycoprotein are selected, retrieved, and expanded. We applied the approach to human recombinant erythropoietin (rhEPO)-producing CHO cells and verified the selection of a single CHO cell that produces rhEPO with a high sialylation degree. Human erythropoietin (hEPO) bearing highly sialylated oligosaccharide was shown to display a much longer plasma half-life, resulting in high therapeutic efficacy. This method may find widespread use in the clonal selection for the production of other glycoproteins with specific glycosylation as well as analysis of the heterogeneity in cell populations in a high-throughput manner.

  20. Effective Viscosity of Microswimmer Suspensions

    NASA Astrophysics Data System (ADS)

    Rafaï, Salima; Jibuti, Levan; Peyla, Philippe

    2010-03-01

    The measurement of a quantitative and macroscopic parameter to estimate the global motility of a large population of swimming biological cells is a challenge. Experiments on the rheology of active suspensions have been performed. Effective viscosity of sheared suspensions of live unicellular motile microalgae (Chlamydomonas Reinhardtii) is far greater than for suspensions containing the same volume fraction of dead cells. In addition, suspensions show shear thinning behavior. We relate these macroscopic measurements to the orientation of individual swimming cells under flow and discuss our results in the light of several existing models.

  1. Effective viscosity of microswimmer suspensions.

    PubMed

    Rafaï, Salima; Jibuti, Levan; Peyla, Philippe

    2010-03-05

    The measurement of a quantitative and macroscopic parameter to estimate the global motility of a large population of swimming biological cells is a challenge. Experiments on the rheology of active suspensions have been performed. Effective viscosity of sheared suspensions of live unicellular motile microalgae (Chlamydomonas Reinhardtii) is far greater than for suspensions containing the same volume fraction of dead cells. In addition, suspensions show shear thinning behavior. We relate these macroscopic measurements to the orientation of individual swimming cells under flow and discuss our results in the light of several existing models.

  2. Controls of maglev suspension systems

    SciTech Connect

    Cai, Y.; Zhu, S.; Chen, S.S.; Rote, D.M.

    1993-06-01

    This study investigates alternative control designs of maglev vehicle suspension systems. Active and semi-active control law designs are introduced into primary and secondary suspensions of maglev vehicles. A one-dimensional vehicle with two degrees of freedom, to simulate the German Transrapid Maglev System, is used for suspension control designs. The transient and frequency responses of suspension systems and PSDs of vehicle accelerations are calculated to evaluate different control designs. The results show that active and semi-active control designs indeed improve the response of vehicle and provide an acceptable ride comfort for maglev systems.

  3. 20 CFR 416.1320 - Suspensions; general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Suspensions; general. 416.1320 Section 416..., BLIND, AND DISABLED Suspensions and Terminations § 416.1320 Suspensions; general. (a) When suspension is proper. Suspension of benefit payments is required when a recipient is alive but no longer meets...

  4. Fingerprint analysis of Hibiscus mutabilis L. leaves based on ultra performance liquid chromatography with photodiode array detector combined with similarity analysis and hierarchical clustering analysis methods

    PubMed Central

    Liang, Xianrui; Ma, Meiling; Su, Weike

    2013-01-01

    Background: A method for chemical fingerprint analysis of Hibiscus mutabilis L. leaves was developed based on ultra performance liquid chromatography with photodiode array detector (UPLC-PAD) combined with similarity analysis (SA) and hierarchical clustering analysis (HCA). Materials and Methods: 10 batches of Hibiscus mutabilis L. leaves samples were collected from different regions of China. UPLC-PAD was employed to collect chemical fingerprints of Hibiscus mutabilis L. leaves. Results: The relative standard deviations (RSDs) of the relative retention times (RRT) and relative peak areas (RPA) of 10 characteristic peaks (one of them was identified as rutin) in precision, repeatability and stability test were less than 3%, and the method of fingerprint analysis was validated to be suitable for the Hibiscus mutabilis L. leaves. Conclusions: The chromatographic fingerprints showed abundant diversity of chemical constituents qualitatively in the 10 batches of Hibiscus mutabilis L. leaves samples from different locations by similarity analysis on basis of calculating the correlation coefficients between each two fingerprints. Moreover, the HCA method clustered the samples into four classes, and the HCA dendrogram showed the close or distant relations among the 10 samples, which was consistent to the SA result to some extent. PMID:23930008

  5. An analysis of the origin of differences between measured and simulated fields produced by a 15-element ultrasound phased array.

    PubMed

    Aitkenhead, Adam H; Mills, John A; Wilson, Adrian J

    2010-03-01

    Modeling provides an attractive approach for the design of phased array ultrasound transducers for hyperthermia. However, measurements on physical transducers reveal differences from the idealized field profiles predicted by simulation. In this paper we report a method of analyzing the origins of these differences. The measured performance of a 15-element sparse phased array is described and compared with simulated fields calculated using the point source method. It highlighted two notable differences: First, that the focal region was located closer to the surface of the physical transducer than in the simulated fields; and second, that numerous intensity maxima were present between the surface of the transducer and the focal zone in the experimental data, but not in the simulated fields. We identified six factors that could potentially affect the field but were not taken into account by the default simulations, and we performed a sensitivity analysis on these: (i) Variation in the amplitude of the output from each element, (ii) the presence of square-wave harmonics in the drive signals, (iii) nonpistonlike vibration of elements, (iv) quantization of the applied phases, (v) errors in the spatial positioning of each element; and (vi) interelement cross-coupling. Both the independent impact of each factor and the interactions between multiple factors were analyzed by using a full-factorial experimental design composed of 64 (2(6)) simulations. The results indicated that nonpistonlike motion of elements is likely to be the primary cause of differences between the measured and modelled fields. Determination of the precise vibrational modes of elements in an array is complex and would require full finite element analysis. However, the simple vibrational mode considered within the present work, corresponding to the addition of a surface Rayleigh wave originating at the element center and propagating radially, produced simulation results that were in good agreement with

  6. Meta-GWAS and Meta-Analysis of Exome Array Studies Do Not Reveal Genetic Determinants of Serum Hepcidin

    PubMed Central

    Galesloot, Tessel E.; van Dijk, Freerk; Geurts-Moespot, Anneke J.; Girelli, Domenico; Kiemeney, Lambertus A. L. M.; Sweep, Fred C. G. J.; Swertz, Morris A.; van der Meer, Peter; Camaschella, Clara; Toniolo, Daniela; Vermeulen, Sita H.; van der Harst, Pim; Swinkels, Dorine W.

    2016-01-01

    Serum hepcidin concentration is regulated by iron status, inflammation, erythropoiesis and numerous other factors, but underlying processes are incompletely understood. We studied the association of common and rare single nucleotide variants (SNVs) with serum hepcidin in one Italian study and two large Dutch population-based studies. We genotyped common SNVs with genome-wide association study (GWAS) arrays and subsequently performed imputation using the 1000 Genomes reference panel. Cohort-specific GWAS were performed for log-transformed serum hepcidin, adjusted for age and gender, and results were combined in a fixed-effects meta-analysis (total N 6,096). Six top SNVs (p<5x10-6) were genotyped in 3,821 additional samples, but associations were not replicated. Furthermore, we meta-analyzed cohort-specific exome array association results of rare SNVs with serum hepcidin that were available for two of the three cohorts (total N 3,226), but no exome-wide significant signal (p<1.4x10-6) was identified. Gene-based meta-analyses revealed 19 genes that showed significant association with hepcidin. Our results suggest the absence of common SNVs and rare exonic SNVs explaining a large proportion of phenotypic variation in serum hepcidin. We recommend extension of our study once additional substantial cohorts with hepcidin measurements, GWAS and/or exome array data become available in order to increase power to identify variants that explain a smaller proportion of hepcidin variation. In addition, we encourage follow-up of the potentially interesting genes that resulted from the gene-based analysis of low-frequency and rare variants. PMID:27846281

  7. The Psychological Challenges of Replacing Conventional Karyotyping with Genomic SNP Array Analysis in Prenatal Testing.

    PubMed

    Riedijk, Sam; Diderich, Karin E M; van der Steen, Sanne L; Govaerts, Lutgarde C P; Joosten, Marieke; Knapen, Maarten F C M; de Vries, Femke A T; van Opstal, Diane; Tibben, Aad; Galjaard, Robert-Jan H

    2014-07-03

    Pregnant couples tend to prefer a maximum of information about the health of their fetus. Therefore, we implemented whole genome microarray instead of conventional karyotyping (CK) for all indications for prenatal diagnosis (PND). The array detects more clinically relevant anomalies, including early onset disorders, not related to the indication and more genetic anomalies of yet unquantifiable risk, so-called susceptibility loci (SL) for mainly neurodevelopmental disorders. This manuscript highlights the psychological challenges in prenatal genetic counselling when using the array and provides counselling suggestions. First, we suggest that pre-test decision counselling should emphasize deliberation about what pregnant couples wish to learn about the future health of their fetus more than information about possible outcomes. Second, pregnant couples need support in dealing with SL. Therefore, in order to consider the SL in a proportionate perspective, the presence of phenotypes associated with SL in the family, the incidence of a particular SL in control populations and in postnatally ascertained patients needs highlighting during post-test genetic counselling. Finally, the decision that couples need to make about the course of their pregnancy is more complicated when the expected phenotype is variable and not quantifiable. Therefore, during post-test psychological counseling, couples should concretize the options of continuing and ending their pregnancy; all underlying feelings and thoughts should be made explicit, as well as the couple's resources, in order to attain adequate decision-making. As such, pre- and post-test counselling aids pregnant couples in handling the uncertainties that may accompany offering a broader scope of genetic PND using the array.

  8. The Psychological Challenges of Replacing Conventional Karyotyping with Genomic SNP Array Analysis in Prenatal Testing

    PubMed Central

    Riedijk, Sam; Diderich, Karin E. M.; van der Steen, Sanne L.; Govaerts, Lutgarde C. P.; Joosten, Marieke; Knapen, Maarten F. C. M.; de Vries, Femke A. T.; van Opstal, Diane; Tibben, Aad; Galjaard, Robert-Jan H.

    2014-01-01

    Pregnant couples tend to prefer a maximum of information about the health of their fetus. Therefore, we implemented whole genome microarray instead of conventional karyotyping (CK) for all indications for prenatal diagnosis (PND). The array detects more clinically relevant anomalies, including early onset disorders, not related to the indication and more genetic anomalies of yet unquantifiable risk, so-called susceptibility loci (SL) for mainly neurodevelopmental disorders. This manuscript highlights the psychological challenges in prenatal genetic counselling when using the array and provides counselling suggestions. First, we suggest that pre-test decision counselling should emphasize deliberation about what pregnant couples wish to learn about the future health of their fetus more than information about possible outcomes. Second, pregnant couples need support in dealing with SL. Therefore, in order to consider the SL in a proportionate perspective, the presence of phenotypes associated with SL in the family, the incidence of a particular SL in control populations and in postnatally ascertained patients needs highlighting during post-test genetic counselling. Finally, the decision that couples need to make about the course of their pregnancy is more complicated when the expected phenotype is variable and not quantifiable. Therefore, during post-test psychological counseling, couples should concretize the options of continuing and ending their pregnancy; all underlying feelings and thoughts should be made explicit, as well as the couple’s resources, in order to attain adequate decision-making. As such, pre- and post-test counselling aids pregnant couples in handling the uncertainties that may accompany offering a broader scope of genetic PND using the array. PMID:26237473

  9. [Finite element analysis of temperature field of retina by electrical stimulation with microelectrode array].

    PubMed

    Wang, Wei; Qiao, Qingli; Gao, Weiping; Wu, Jun

    2014-12-01

    We studied the influence of electrode array parameters on temperature distribution to the retina during the use of retinal prosthesis in order to avoid thermal damage to retina caused by long-term electrical stimulation. Based on real epiretinal prosthesis, a three-dimensional model of electrical stimulation for retina with 4 X 4 microelectrode array had been established using the finite element software (COMSOL Multiphysics). The steady-state temperature field of electrical stimulation of the retina was calculated, and the effects of the electrode parameters such as the distance between the electrode contacts, the materials and area of the electrode contact on temperature field were considered. The maximum increase in the retina steady temperature was about 0. 004 degrees C with practical stimulation current. When the distance between the electrode contacts was changed from 130 microm to 520 microm, the temperature was reduced by about 0.006 microC. When the contact radius was doubled from 130 microm to 260 microm, the temperature decrease was about 0.005 degrees C. It was shown that there were little temperature changes in the retina with a 4 x 4 epiretinal microelectrode array, reflecting the safety of electrical stimulation. It was also shown that the maximum temperature in the retina decreased with increasing the distance between the electrode contacts, as well as increasing the area of electrode contact. However, the change of the maximum temperature was very small when the distance became larger than the diameter of electrode contact. There was no significant difference in the effects of temperature increase among the different electrode materials. Rational selection of the distance between the electrode contacts and their area in electrode design can reduce the temperature rise induced by electrical stimulation.

  10. Methods for Room Acoustic Analysis and Synthesis using a Monopole-Dipole Microphone Array

    NASA Technical Reports Server (NTRS)

    Abel, J. S.; Begault, Durand R.; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    In recent work, a microphone array consisting of an omnidirectional microphone and colocated dipole microphones having orthogonally aligned dipole axes was used to examine the directional nature of a room impulse response. The arrival of significant reflections was indicated by peaks in the power of the omnidirectional microphone response; reflection direction of arrival was revealed by comparing zero-lag crosscorrelations between the omnidirectional response and the dipole responses to the omnidirectional response power to estimate arrival direction cosines with respect to the dipole axes.

  11. Dense suspension splash

    NASA Astrophysics Data System (ADS)

    Dodge, Kevin M.; Peters, Ivo R.; Ellowitz, Jake; Schaarsberg, Martin H. Klein; Jaeger, Heinrich M.; Zhang, Wendy W.

    2014-11-01

    Impact of a dense suspension drop onto a solid surface at speeds of several meters-per-second splashes by ejecting individual liquid-coated particles. Suppression or reduction of this splash is important for thermal spray coating and additive manufacturing. Accomplishing this aim requires distinguishing whether the splash is generated by individual scattering events or by collective motion reminiscent of liquid flow. Since particle inertia dominates over surface tension and viscous drag in a strong splash, we model suspension splash using a discrete-particle simulation in which the densely packed macroscopic particles experience inelastic collisions but zero friction or cohesion. Numerical results based on this highly simplified model are qualitatively consistent with observations. They also show that approximately 70% of the splash is generated by collective motion. Here an initially downward-moving particle is ejected into the splash because it experiences a succession of low-momentum-change collisions whose effects do not cancel but instead accumulate. The remainder of the splash is generated by scattering events in which a small number of high-momentum-change collisions cause a particle to be ejected upwards. Current Address: Physics of Fluids Group, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.

  12. Morphometric analysis of murine skin wound healing: standardization of experimental procedures and impact of an advanced multitissue array technique.

    PubMed

    Gerharz, Michael; Baranowsky, Ankev; Siebolts, Udo; Eming, Sabine; Nischt, Roswitha; Krieg, Thomas; Wickenhauser, Claudia

    2007-01-01

    Morphometric data based on skin wounding offer important information for the characterization of the phenotype of transgenic mouse models. The goal of this study was the comparison of technical procedures concerning wounding, processing, and evaluation of samples in different mouse strains. The multitissue array technique was used to estimate its adaptability for standardized analysis in wound healing. Skin wounds between days 1 and 14 after wounding were analyzed. The influence of mouse strain (C57BI/6 vs. FVB/N mice), sex, size of the punch biopsies, and preparation of the tissue sections was investigated on 94 mice. The parameters distance between the migration tongues (deltaMT) and surface not covered by epithelium were evaluated to describe the reepithelialization, and the distance between the adnexa was chosen to measure wound contraction. In addition, the techniques to measure the area of granulation tissue (GT) were evaluated. The data illustrate the requirement of standardized conditions for skin wound-healing experiments and demonstrate that histological preparation in serial sections is mandatory to detect slight differences in wound contraction. For the analysis of cellular composition in GT, multitissue arrays are useful tools in wound-healing studies.

  13. Feasibility analysis of XSOLANTRA: A mission concept to detect exoplanets with an array of CubeSats

    NASA Astrophysics Data System (ADS)

    Banazadeh, P.; Lazio, J.; Jones, D.; Scharf, D. P.; Fowler, W.; Aladangady, C.

    Seeking “ nearby habitable worlds” was one of three science themes identified in the Astronomy Decadal Survey. Hundreds of extrasolar planets are known, but magnetic fields are likely required for these planets to be habitable. As of today, no direct constraints on the magnetic field characteristics of extrasolar planets exist. The ExtraSolar Observing Low-frequency Array of Nano Satellites for Radio Astronomy (XSOLANTRA), formerly known as XSOLARA is a feasibility study of a student designed, built, and tested micro-satellite mission to a Distant Retrograde Orbit (DRO) around Earth. XSOLANTRA will look at the Electron Cyclotron Maser Emission generated by the interaction between stellar wind and a planetary magnetosphere from which interior composition and atmospheric shielding can be inferred. The science instrument for XSOLANTRA is the entire array of fourteen CubeSats operating together as an interferometer. The fourteen CubeSats will be stacked on a SHuttle Expendable Rocket for Payload Augmentation (SHERPA) vehicle as a payload and will be deployed once arrived at DRO. A feasibility study was conducted to demonstrate that a CubeSat mission with cost of no more than $60 million is capable of detecting extrasolar planets. The study showed that a CubeSat mission within these constraints is possible; however, some questions still remain unanswered. This paper summarizes the mission concept starting from the science requirements, key mission design decisions, component level feasibility analysis and management and cost analysis.

  14. Musical-Noise Analysis in Methods of Integrating Microphone Array and Spectral Subtraction Based on Higher-Order Statistics

    NASA Astrophysics Data System (ADS)

    Takahashi, Yu; Saruwatari, Hiroshi; Shikano, Kiyohiro; Kondo, Kazunobu

    2010-12-01

    We conduct an objective analysis on musical noise generated by two methods of integrating microphone array signal processing and spectral subtraction. To obtain better noise reduction, methods of integrating microphone array signal processing and nonlinear signal processing have been researched. However, nonlinear signal processing often generates musical noise. Since such musical noise causes discomfort to users, it is desirable that musical noise is mitigated. Moreover, it has been recently reported that higher-order statistics are strongly related to the amount of musical noise generated. This implies that it is possible to optimize the integration method from the viewpoint of not only noise reduction performance but also the amount of musical noise generated. Thus, we analyze the simplest methods of integration, that is, the delay-and-sum beamformer and spectral subtraction, and fully clarify the features of musical noise generated by each method. As a result, it is clarified that a specific structure of integration is preferable from the viewpoint of the amount of generated musical noise. The validity of the analysis is shown via a computer simulation and a subjective evaluation.

  15. Parameters analysis for assistant cables of system for transient main cable and catwalk of long-span suspension bridges at construction stages

    NASA Astrophysics Data System (ADS)

    Li, Shengli; Ou, Jinping

    2009-03-01

    On the basis of static, dynamic and transient analysis for the prestressing cable structures, the parameters to control the vibration of the system for transient main cables and catwalk of some long-span suspension bridge at the construction stages with the assistant cables are investigated adopting the method of the finite element considering the geometry nonlinearity. The review and prospect to control vibration with assistant cables are summarized, the finite element modeling of the system for transient main cables and catwalk is established, and the influence of the position of the assistant cables, disposed fashion and the tensile forces upon the critical frequencies of the system for transient main cables and catwalk is researched. At the same time, the effect of the damp and the tensile forces of the assistant cables on the equivalent damping ratio of the system for transient main cables and catwalk inside and outside the plane is studied and the effect to control the vibration of the system is analysed. In the end, the influence of the transformation for the tensile forces about assistant cables upon those of the transient main cables and catwalk is also investigated. Results show that, to increase the critical frequencies of the system, the assistant cables should be laid vertically with the main cables and be located in interim span or between the tower and interim span, and to increase the amount of the assistant cables can increase the critical frequencies ,and to increase the rigidities of the assistant cables can improve the ones of the transient main cables but decrease the anti-torsion ability of the catwalks, and to increase the damp of the assistant cables can improve the vibration of the transient main cables inside and outside the plane but the result is little outside the plane, and in addition the effect of the rigidities of the assistant cables is larger outside the plane but is little inside the plane. The results also show that the

  16. Design and analysis of a novel virtual gyroscope with multi-gyroscope and accelerometer array

    NASA Astrophysics Data System (ADS)

    Luo, Zhang; Liu, Chaojun; Yu, Shuai; Zhang, Shengzhi; Liu, Sheng

    2016-08-01

    A new virtual gyroscope with multi-gyroscope and accelerometer array (MGAA) is proposed in this article for improving the performance of angular rate measurement. Outputs of the virtual gyroscope are obtained by merging the signals from gyroscopes and accelerometers through a novel Kalman filter, which intentionally takes the consideration of the MEMS gyroscope error model and kinematics theory of rigid body. A typical configuration of the virtual gyroscope, consisting of four accelerometers and three gyroscopes mounted on designated positions, is initiated to verify the feasibility of the virtual gyroscope with MGAA. Static test and dynamic test are performed subsequently to evaluate its performance. The angular random walk (ARW) and bias instability, two static performance parameters of gyroscope, are reduced from 0.019°/√s and 14.4°/h to 0.0074°/√s and 8.7°/h, respectively. The average root mean square error (RMSE) is reduced from 0.274°/s to 0.133°/s under dynamic test. Compared with the published multi-gyroscope array method, the virtual gyroscope proposed here has a better performance both in static and dynamic tests, with improvement factors of ARW and RMSE about 44.1% and 44.5% higher, respectively.

  17. Design and analysis of a novel virtual gyroscope with multi-gyroscope and accelerometer array.

    PubMed

    Luo, Zhang; Liu, Chaojun; Yu, Shuai; Zhang, Shengzhi; Liu, Sheng

    2016-08-01

    A new virtual gyroscope with multi-gyroscope and accelerometer array (MGAA) is proposed in this article for improving the performance of angular rate measurement. Outputs of the virtual gyroscope are obtained by merging the signals from gyroscopes and accelerometers through a novel Kalman filter, which intentionally takes the consideration of the MEMS gyroscope error model and kinematics theory of rigid body. A typical configuration of the virtual gyroscope, consisting of four accelerometers and three gyroscopes mounted on designated positions, is initiated to verify the feasibility of the virtual gyroscope with MGAA. Static test and dynamic test are performed subsequently to evaluate its performance. The angular random walk (ARW) and bias instability, two static performance parameters of gyroscope, are reduced from 0.019°/√s and 14.4°/h to 0.0074°/√s and 8.7°/h, respectively. The average root mean square error (RMSE) is reduced from 0.274°/s to 0.133°/s under dynamic test. Compared with the published multi-gyroscope array method, the virtual gyroscope proposed here has a better performance both in static and dynamic tests, with improvement factors of ARW and RMSE about 44.1% and 44.5% higher, respectively.

  18. Performance analysis of MIMO FSO systems with radial array beams and finite sized detectors

    NASA Astrophysics Data System (ADS)

    Gökçe, Muhsin C.; Kamacıoǧlu, Canan; Uysal, Murat; Baykal, Yahya

    2014-10-01

    Multiple-input multiple-output (MIMO) systems are employed in free space optical (FSO) links to mitigate the degrading effects of atmospheric turbulence. In this paper, we consider a MIMO FSO system with practical transmitter and receiver configurations that consists of a radial laser array with Gaussian beams and finite sized detectors. We formulate the average received intensity and the power scinitillation as a function of the receiver coordinates in the presence of weak atmospheric turbulence by using the extended Huygens-Fresnel principle. Then, integrations over the finite sized multiple detectors are performed and the effect of the receiver aperture averaging is quantified. We further derive an outage probability expression of this MIMO system in the presence of turbulence-induced fading channels. Using the derived expressions, we demonstrate the effect of several practical system parameters such as the ring radius, the number of array beamlets, the source size, the link length, structure constant and the receiver aperture radius on the system performance.

  19. Performance analysis of high frequency single-site-location antenna arrays using numerical electromagnetic modeling

    NASA Astrophysics Data System (ADS)

    Schiantarelli, Harry T.

    1990-09-01

    Electronic support measures (ESM) systems play an increasingly important role in modern warfare and can influence the outcome of a military engagement. The application of ESM can be extended to anti-guerrilla and anti-drug operations where law enforcement agencies can exploit the fact that their presence is inducing the outlaw to depend more on radio communications to coordinate their activities. When a propagation path of no more than one reflection at the ionosphere (1-hop) can be assumed, position of an HF emitter can be determined by a single observing site using vertical triangulation, provided that the height of the ionosphere at the point where the radio wave is reflected, can be determined. This technique is known as high frequency direction finding single-site-location (HFDF SSL). This thesis analyzes the HFDF SSL error in measuring the direction of arrival of the signal, how this error is generated by the antenna array and its effect on emitter location. The characteristics of the two antenna arrays used by a specific HFDF SSL system that implements the phase-interferometer techniques were studied using electromagnetic modeling.

  20. Information theory analysis of sensor-array imaging systems for computer vision

    NASA Technical Reports Server (NTRS)

    Huck, F. O.; Fales, C. L.; Park, S. K.; Samms, R. W.; Self, M. O.

    1983-01-01

    Information theory is used to assess the performance of sensor-array imaging systems, with emphasis on the performance obtained with image-plane signal processing. By electronically controlling the spatial response of the imaging system, as suggested by the mechanism of human vision, it is possible to trade-off edge enhancement for sensitivity, increase dynamic range, and reduce data transmission. Computational results show that: signal information density varies little with large variations in the statistical properties of random radiance fields; most information (generally about 85 to 95 percent) is contained in the signal intensity transitions rather than levels; and performance is optimized when the OTF of the imaging system is nearly limited to the sampling passband to minimize aliasing at the cost of blurring, and the SNR is very high to permit the retrieval of small spatial detail from the extensively blurred signal. Shading the lens aperture transmittance to increase depth of field and using a regular hexagonal sensor-array instead of square lattice to decrease sensitivity to edge orientation also improves the signal information density up to about 30 percent at high SNRs.