WorldWideScience

Sample records for highly accurate detection

  1. A Comprehensive Strategy for Accurate Mutation Detection of the Highly Homologous PMS2.

    Science.gov (United States)

    Li, Jianli; Dai, Hongzheng; Feng, Yanming; Tang, Jia; Chen, Stella; Tian, Xia; Gorman, Elizabeth; Schmitt, Eric S; Hansen, Terah A A; Wang, Jing; Plon, Sharon E; Zhang, Victor Wei; Wong, Lee-Jun C

    2015-09-01

    Germline mutations in the DNA mismatch repair gene PMS2 underlie the cancer susceptibility syndrome, Lynch syndrome. However, accurate molecular testing of PMS2 is complicated by a large number of highly homologous sequences. To establish a comprehensive approach for mutation detection of PMS2, we have designed a strategy combining targeted capture next-generation sequencing (NGS), multiplex ligation-dependent probe amplification, and long-range PCR followed by NGS to simultaneously detect point mutations and copy number changes of PMS2. Exonic deletions (E2 to E9, E5 to E9, E8, E10, E14, and E1 to E15), duplications (E11 to E12), and a nonsense mutation, p.S22*, were identified. Traditional multiplex ligation-dependent probe amplification and Sanger sequencing approaches cannot differentiate the origin of the exonic deletions in the 3' region when PMS2 and PMS2CL share identical sequences as a result of gene conversion. Our approach allows unambiguous identification of mutations in the active gene with a straightforward long-range-PCR/NGS method. Breakpoint analysis of multiple samples revealed that recurrent exon 14 deletions are mediated by homologous Alu sequences. Our comprehensive approach provides a reliable tool for accurate molecular analysis of genes containing multiple copies of highly homologous sequences and should improve PMS2 molecular analysis for patients with Lynch syndrome. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  2. A highly accurate wireless digital sun sensor based on profile detecting and detector multiplexing technologies

    Science.gov (United States)

    Wei, Minsong; Xing, Fei; You, Zheng

    2017-01-01

    The advancing growth of micro- and nano-satellites requires miniaturized sun sensors which could be conveniently applied in the attitude determination subsystem. In this work, a profile detecting technology based high accurate wireless digital sun sensor was proposed, which could transform a two-dimensional image into two-linear profile output so that it can realize a high update rate under a very low power consumption. A multiple spots recovery approach with an asymmetric mask pattern design principle was introduced to fit the multiplexing image detector method for accuracy improvement of the sun sensor within a large Field of View (FOV). A FOV determination principle based on the concept of FOV region was also proposed to facilitate both sub-FOV analysis and the whole FOV determination. A RF MCU, together with solar cells, was utilized to achieve the wireless and self-powered functionality. The prototype of the sun sensor is approximately 10 times lower in size and weight compared with the conventional digital sun sensor (DSS). Test results indicated that the accuracy of the prototype was 0.01° within a cone FOV of 100°. Such an autonomous DSS could be equipped flexibly on a micro- or nano-satellite, especially for highly accurate remote sensing applications.

  3. Highly accurate determination of relative gamma-ray detection efficiency for Ge detector and its application

    International Nuclear Information System (INIS)

    Miyahara, H.; Mori, C.; Fleming, R.F.; Dewaraja, Y.K.

    1997-01-01

    When quantitative measurements of γ-rays using High-Purity Ge (HPGe) detectors are made for a variety of applications, accurate knowledge of oy-ray detection efficiency is required. The emission rates of γ-rays from sources can be determined quickly in the case that the absolute peak efficiency is calibrated. On the other hand, the relative peak efficiencies can be used for determination of intensity ratios for plural samples and for comparison to the standard source. Thus, both absolute and relative detection efficiencies are important in use of γ-ray detector. The objective of this work is to determine the relative gamma-ray peak detection efficiency for an HPGe detector with the uncertainty approaching 0.1% . We used some nuclides which emit at least two gamma-rays with energies from 700 to 2400 keV for which the relative emission probabilities are known with uncertainties much smaller than 0.1%. The relative peak detection efficiencies were calculated from the measurements of the nuclides, 46 Sc, 48 Sc, 60 Co and 94 Nb, emitting two γ- rays with the emission probabilities of almost unity. It is important that various corrections for the emission probabilities, the cascade summing effect, and the self-absorption are small. A third order polynomial function on both logarithmic scales of energy and efficiency was fitted to the data, and the peak efficiency predicted at certain energy from covariance matrix showed the uncertainty less than 0.5% except for near 700 keV. As an application, the emission probabilities of the 1037.5 and 1212.9 keV γ-rays for 48 Sc were determined using the function of the highly precise relative peak efficiency. Those were 0.9777+0,.00079 and 0.02345+0.00017 for the 1037.5 and 1212.9 keV γ-rays, respectively. The sum of these probabilities is close to unity within the uncertainty which means that the certainties of the results are high and the accuracy has been improved considerably

  4. Accurate RNA consensus sequencing for high-fidelity detection of transcriptional mutagenesis-induced epimutations.

    Science.gov (United States)

    Reid-Bayliss, Kate S; Loeb, Lawrence A

    2017-08-29

    Transcriptional mutagenesis (TM) due to misincorporation during RNA transcription can result in mutant RNAs, or epimutations, that generate proteins with altered properties. TM has long been hypothesized to play a role in aging, cancer, and viral and bacterial evolution. However, inadequate methodologies have limited progress in elucidating a causal association. We present a high-throughput, highly accurate RNA sequencing method to measure epimutations with single-molecule sensitivity. Accurate RNA consensus sequencing (ARC-seq) uniquely combines RNA barcoding and generation of multiple cDNA copies per RNA molecule to eliminate errors introduced during cDNA synthesis, PCR, and sequencing. The stringency of ARC-seq can be scaled to accommodate the quality of input RNAs. We apply ARC-seq to directly assess transcriptome-wide epimutations resulting from RNA polymerase mutants and oxidative stress.

  5. High resolution melting analysis: a rapid and accurate method to detect CALR mutations.

    Directory of Open Access Journals (Sweden)

    Cristina Bilbao-Sieyro

    Full Text Available The recent discovery of CALR mutations in essential thrombocythemia (ET and primary myelofibrosis (PMF patients without JAK2/MPL mutations has emerged as a relevant finding for the molecular diagnosis of these myeloproliferative neoplasms (MPN. We tested the feasibility of high-resolution melting (HRM as a screening method for rapid detection of CALR mutations.CALR was studied in wild-type JAK2/MPL patients including 34 ET, 21 persistent thrombocytosis suggestive of MPN and 98 suspected secondary thrombocytosis. CALR mutation analysis was performed through HRM and Sanger sequencing. We compared clinical features of CALR-mutated versus 45 JAK2/MPL-mutated subjects in ET.Nineteen samples showed distinct HRM patterns from wild-type. Of them, 18 were mutations and one a polymorphism as confirmed by direct sequencing. CALR mutations were present in 44% of ET (15/34, 14% of persistent thrombocytosis suggestive of MPN (3/21 and none of the secondary thrombocytosis (0/98. Of the 18 mutants, 9 were 52 bp deletions, 8 were 5 bp insertions and other was a complex mutation with insertion/deletion. No mutations were found after sequencing analysis of 45 samples displaying wild-type HRM curves. HRM technique was reproducible, no false positive or negative were detected and the limit of detection was of 3%.This study establishes a sensitive, reliable and rapid HRM method to screen for the presence of CALR mutations.

  6. Detecting Cancer Quickly and Accurately

    Science.gov (United States)

    Gourley, Paul; McDonald, Anthony; Hendricks, Judy; Copeland, Guild; Hunter, John; Akhil, Ohmar; Capps, Heather; Curry, Marc; Skirboll, Steve

    2000-03-01

    We present a new technique for high throughput screening of tumor cells in a sensitive nanodevice that has the potential to quickly identify a cell population that has begun the rapid protein synthesis and mitosis characteristic of cancer cell proliferation. Currently, pathologists rely on microscopic examination of cell morphology using century-old staining methods that are labor-intensive, time-consuming and frequently in error. New micro-analytical methods for automated, real time screening without chemical modification are critically needed to advance pathology and improve diagnoses. We have teamed scientists with physicians to create a microlaser biochip (based upon our R&D award winning bio-laser concept)1 which evaluates tumor cells by quantifying their growth kinetics. The key new discovery was demonstrating that the lasing spectra are sensitive to the biomolecular mass in the cell, which changes the speed of light in the laser microcavity. Initial results with normal and cancerous human brain cells show that only a few hundred cells -- the equivalent of a billionth of a liter -- are required to detect abnormal growth. The ability to detect cancer in such a minute tissue sample is crucial for resecting a tumor margin or grading highly localized tumor malignancy. 1. P. L. Gourley, NanoLasers, Scientific American, March 1998, pp. 56-61. This work supported under DOE contract DE-AC04-94AL85000 and the Office of Basic Energy Sciences.

  7. Heap: a highly sensitive and accurate SNP detection tool for low-coverage high-throughput sequencing data

    KAUST Repository

    Kobayashi, Masaaki

    2017-04-20

    Recent availability of large-scale genomic resources enables us to conduct so called genome-wide association studies (GWAS) and genomic prediction (GP) studies, particularly with next-generation sequencing (NGS) data. The effectiveness of GWAS and GP depends on not only their mathematical models, but the quality and quantity of variants employed in the analysis. In NGS single nucleotide polymorphism (SNP) calling, conventional tools ideally require more reads for higher SNP sensitivity and accuracy. In this study, we aimed to develop a tool, Heap, that enables robustly sensitive and accurate calling of SNPs, particularly with a low coverage NGS data, which must be aligned to the reference genome sequences in advance. To reduce false positive SNPs, Heap determines genotypes and calls SNPs at each site except for sites at the both ends of reads or containing a minor allele supported by only one read. Performance comparison with existing tools showed that Heap achieved the highest F-scores with low coverage (7X) restriction-site associated DNA sequencing reads of sorghum and rice individuals. This will facilitate cost-effective GWAS and GP studies in this NGS era. Code and documentation of Heap are freely available from https://github.com/meiji-bioinf/heap (29 March 2017, date last accessed) and our web site (http://bioinf.mind.meiji.ac.jp/lab/en/tools.html (29 March 2017, date last accessed)).

  8. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiu-Hua; Ling, Jian, E-mail: lingjian@ynu.edu.cn; Peng, Jun; Cao, Qiu-E., E-mail: qecao@ynu.edu.cn; Ding, Zhong-Tao; Bian, Long-Chun

    2013-10-10

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis.

  9. A colorimetric method for highly sensitive and accurate detection of iodide by finding the critical color in a color change process using silver triangular nanoplates

    International Nuclear Information System (INIS)

    Yang, Xiu-Hua; Ling, Jian; Peng, Jun; Cao, Qiu-E.; Ding, Zhong-Tao; Bian, Long-Chun

    2013-01-01

    Graphical abstract: -- Highlights: •Demonstrated a new colorimetric strategy for iodide detection by silver nanoplates. •The colorimetric strategy is to find the critical color in a color change process. •The colorimetric strategy is more accurate and sensitive than common colorimetry. •Discovered a new morphological transformation phenomenon of silver nanoplates. -- Abstract: In this contribution, we demonstrated a novel colorimetric method for highly sensitive and accurate detection of iodide using citrate-stabilized silver triangular nanoplates (silver TNPs). Very lower concentration of iodide can induce an appreciable color change of silver TNPs solution from blue to yellow by fusing of silver TNPs to nanoparticles, as confirmed by UV–vis absorption spectroscopy and transmission electron microscopy (TEM). The principle of this colorimetric assay is not an ordinary colorimetry, but a new colorimetric strategy by finding the critical color in a color change process. With this strategy, 0.1 μM of iodide can be recognized within 30 min by naked-eyes observation, and lower concentration of iodide down to 8.8 nM can be detected using a spectrophotometer. Furthermore, this high sensitive colorimetric assay has good accuracy, stability and reproducibility comparing with other ordinary colorimetry. We believe this new colorimetric method will open up a fresh insight of simple, rapid and reliable detection of iodide and can find its future application in the biochemical analysis or clinical diagnosis

  10. Rapid and highly accurate detection of Drosophila suzukii, spotted wing Drosophila (Diptera: Drosophilidae) by loop-mediated isothermal amplification assays

    Science.gov (United States)

    Drosophila suzukii, the spotted wing drosophila (SWD), is currently a major pest that causes severe economic losses to thin-skinned, small fruit growers in North America and Europe. The monitoring and early detection of SWD in the field is of the utmost importance for its proper management. Althou...

  11. An accurate, specific, sensitive, high-throughput method based on a microsphere immunoassay for multiplex detection of three viruses and bacterial fruit blotch bacterium in cucurbits.

    Science.gov (United States)

    Charlermroj, Ratthaphol; Makornwattana, Manlika; Himananto, Orawan; Seepiban, Channarong; Phuengwas, Sudtida; Warin, Nuchnard; Gajanandana, Oraprapai; Karoonuthaisiri, Nitsara

    2017-09-01

    To employ a microsphere immunoassay (MIA) to simultaneously detect multiple plant pathogens (potyviruses, Watermelon silver mottle virus, Melon yellow spot virus, and Acidovorax avenae subsp. citrulli) in actual plant samples, several factors need to be optimized and rigorously validated. Here, a simple extraction method using a single extraction buffer was successfully selected to detect the four pathogens in various cucurbit samples (cucumber, cantaloupe, melon, and watermelon). The extraction method and assay performance were validated with inoculated and field cucurbit samples. The MIA showed 98-99% relative accuracy, 97-100% relative specificity and 92-100% relative sensitivity when compared to commercial ELISA kits and reverse transcription PCR. In addition, the MIA was also able to accurately detect multiple-infected field samples. The results demonstrate that one common extraction method for all tested cucurbit samples could be applied to detect multiple pathogens; avoiding the need for multiple protocols to be employed. This multiplex method can therefore be instrumental for high-throughput screening of multiple plant pathogens with many advantages such as a shorter assay time (2.5h) with single assay format, a lower cost of detection ($5 vs $19.7 for 4 pathogens/sample) and less labor requirement. Its multiplex capacity can also be expanded to detect up to 50 different pathogens upon the availability of specific antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. An integrated tool to study MHC region: accurate SNV detection and HLA genes typing in human MHC region using targeted high-throughput sequencing.

    Directory of Open Access Journals (Sweden)

    Hongzhi Cao

    Full Text Available The major histocompatibility complex (MHC is one of the most variable and gene-dense regions of the human genome. Most studies of the MHC, and associated regions, focus on minor variants and HLA typing, many of which have been demonstrated to be associated with human disease susceptibility and metabolic pathways. However, the detection of variants in the MHC region, and diagnostic HLA typing, still lacks a coherent, standardized, cost effective and high coverage protocol of clinical quality and reliability. In this paper, we presented such a method for the accurate detection of minor variants and HLA types in the human MHC region, using high-throughput, high-coverage sequencing of target regions. A probe set was designed to template upon the 8 annotated human MHC haplotypes, and to encompass the 5 megabases (Mb of the extended MHC region. We deployed our probes upon three, genetically diverse human samples for probe set evaluation, and sequencing data show that ∼97% of the MHC region, and over 99% of the genes in MHC region, are covered with sufficient depth and good evenness. 98% of genotypes called by this capture sequencing prove consistent with established HapMap genotypes. We have concurrently developed a one-step pipeline for calling any HLA type referenced in the IMGT/HLA database from this target capture sequencing data, which shows over 96% typing accuracy when deployed at 4 digital resolution. This cost-effective and highly accurate approach for variant detection and HLA typing in the MHC region may lend further insight into immune-mediated diseases studies, and may find clinical utility in transplantation medicine research. This one-step pipeline is released for general evaluation and use by the scientific community.

  13. Towards accurate detection of obfuscated web tracking

    OpenAIRE

    Le, Hoan; Fallace, Federico; Barlet Ros, Pere

    2017-01-01

    Web tracking is currently recognized as one of the most important privacy threats on the Internet. Over the last years, many methodologies have been developed to uncover web trackers. Most of them are based on static code analysis and the use of predefined blacklists. However, our main hypothesis is that web tracking has started to use obfuscated programming, a transformation of code that renders previous detection methodologies ineffective and easy to evade. In this paper, we propose a new m...

  14. Accurate modeling and maximum power point detection of ...

    African Journals Online (AJOL)

    Accurate modeling and maximum power point detection of photovoltaic ... Determination of MPP enables the PV system to deliver maximum available power. ..... adaptive artificial neural network: Proposition for a new sizing procedure.

  15. Accurately Detecting Students' Lies regarding Relational Aggression by Correctional Instructions

    Science.gov (United States)

    Dickhauser, Oliver; Reinhard, Marc-Andre; Marksteiner, Tamara

    2012-01-01

    This study investigates the effect of correctional instructions when detecting lies about relational aggression. Based on models from the field of social psychology, we predict that correctional instruction will lead to a less pronounced lie bias and to more accurate lie detection. Seventy-five teachers received videotapes of students' true denial…

  16. Fast and Accurate Residential Fire Detection Using Wireless Sensor Networks

    NARCIS (Netherlands)

    Bahrepour, Majid; Meratnia, Nirvana; Havinga, Paul J.M.

    2010-01-01

    Prompt and accurate residential fire detection is important for on-time fire extinguishing and consequently reducing damages and life losses. To detect fire sensors are needed to measure the environmental parameters and algorithms are required to decide about occurrence of fire. Recently, wireless

  17. Apparatus for accurately measuring high temperatures

    Science.gov (United States)

    Smith, D.D.

    The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  18. SNPdetector: a software tool for sensitive and accurate SNP detection.

    Directory of Open Access Journals (Sweden)

    Jinghui Zhang

    2005-10-01

    Full Text Available Identification of single nucleotide polymorphisms (SNPs and mutations is important for the discovery of genetic predisposition to complex diseases. PCR resequencing is the method of choice for de novo SNP discovery. However, manual curation of putative SNPs has been a major bottleneck in the application of this method to high-throughput screening. Therefore it is critical to develop a more sensitive and accurate computational method for automated SNP detection. We developed a software tool, SNPdetector, for automated identification of SNPs and mutations in fluorescence-based resequencing reads. SNPdetector was designed to model the process of human visual inspection and has a very low false positive and false negative rate. We demonstrate the superior performance of SNPdetector in SNP and mutation analysis by comparing its results with those derived by human inspection, PolyPhred (a popular SNP detection tool, and independent genotype assays in three large-scale investigations. The first study identified and validated inter- and intra-subspecies variations in 4,650 traces of 25 inbred mouse strains that belong to either the Mus musculus species or the M. spretus species. Unexpected heterozygosity in CAST/Ei strain was observed in two out of 1,167 mouse SNPs. The second study identified 11,241 candidate SNPs in five ENCODE regions of the human genome covering 2.5 Mb of genomic sequence. Approximately 50% of the candidate SNPs were selected for experimental genotyping; the validation rate exceeded 95%. The third study detected ENU-induced mutations (at 0.04% allele frequency in 64,896 traces of 1,236 zebra fish. Our analysis of three large and diverse test datasets demonstrated that SNPdetector is an effective tool for genome-scale research and for large-sample clinical studies. SNPdetector runs on Unix/Linux platform and is available publicly (http://lpg.nci.nih.gov.

  19. Highly accurate surface maps from profilometer measurements

    Science.gov (United States)

    Medicus, Kate M.; Nelson, Jessica D.; Mandina, Mike P.

    2013-04-01

    Many aspheres and free-form optical surfaces are measured using a single line trace profilometer which is limiting because accurate 3D corrections are not possible with the single trace. We show a method to produce an accurate fully 2.5D surface height map when measuring a surface with a profilometer using only 6 traces and without expensive hardware. The 6 traces are taken at varying angular positions of the lens, rotating the part between each trace. The output height map contains low form error only, the first 36 Zernikes. The accuracy of the height map is ±10% of the actual Zernike values and within ±3% of the actual peak to valley number. The calculated Zernike values are affected by errors in the angular positioning, by the centering of the lens, and to a small effect, choices made in the processing algorithm. We have found that the angular positioning of the part should be better than 1?, which is achievable with typical hardware. The centering of the lens is essential to achieving accurate measurements. The part must be centered to within 0.5% of the diameter to achieve accurate results. This value is achievable with care, with an indicator, but the part must be edged to a clean diameter.

  20. Accurate mobile malware detection and classification in the cloud.

    Science.gov (United States)

    Wang, Xiaolei; Yang, Yuexiang; Zeng, Yingzhi

    2015-01-01

    As the dominator of the Smartphone operating system market, consequently android has attracted the attention of s malware authors and researcher alike. The number of types of android malware is increasing rapidly regardless of the considerable number of proposed malware analysis systems. In this paper, by taking advantages of low false-positive rate of misuse detection and the ability of anomaly detection to detect zero-day malware, we propose a novel hybrid detection system based on a new open-source framework CuckooDroid, which enables the use of Cuckoo Sandbox's features to analyze Android malware through dynamic and static analysis. Our proposed system mainly consists of two parts: anomaly detection engine performing abnormal apps detection through dynamic analysis; signature detection engine performing known malware detection and classification with the combination of static and dynamic analysis. We evaluate our system using 5560 malware samples and 6000 benign samples. Experiments show that our anomaly detection engine with dynamic analysis is capable of detecting zero-day malware with a low false negative rate (1.16 %) and acceptable false positive rate (1.30 %); it is worth noting that our signature detection engine with hybrid analysis can accurately classify malware samples with an average positive rate 98.94 %. Considering the intensive computing resources required by the static and dynamic analysis, our proposed detection system should be deployed off-device, such as in the Cloud. The app store markets and the ordinary users can access our detection system for malware detection through cloud service.

  1. An Integrative Approach to Accurate Vehicle Logo Detection

    Directory of Open Access Journals (Sweden)

    Hao Pan

    2013-01-01

    required for many applications in intelligent transportation systems and automatic surveillance. The task is challenging considering the small target of logos and the wide range of variability in shape, color, and illumination. A fast and reliable vehicle logo detection approach is proposed following visual attention mechanism from the human vision. Two prelogo detection steps, that is, vehicle region detection and a small RoI segmentation, rapidly focalize a small logo target. An enhanced Adaboost algorithm, together with two types of features of Haar and HOG, is proposed to detect vehicles. An RoI that covers logos is segmented based on our prior knowledge about the logos’ position relative to license plates, which can be accurately localized from frontal vehicle images. A two-stage cascade classier proceeds with the segmented RoI, using a hybrid of Gentle Adaboost and Support Vector Machine (SVM, resulting in precise logo positioning. Extensive experiments were conducted to verify the efficiency of the proposed scheme.

  2. Highly Accurate Prediction of Jobs Runtime Classes

    OpenAIRE

    Reiner-Benaim, Anat; Grabarnick, Anna; Shmueli, Edi

    2016-01-01

    Separating the short jobs from the long is a known technique to improve scheduling performance. In this paper we describe a method we developed for accurately predicting the runtimes classes of the jobs to enable this separation. Our method uses the fact that the runtimes can be represented as a mixture of overlapping Gaussian distributions, in order to train a CART classifier to provide the prediction. The threshold that separates the short jobs from the long jobs is determined during the ev...

  3. Accurate Fall Detection in a Top View Privacy Preserving Configuration.

    Science.gov (United States)

    Ricciuti, Manola; Spinsante, Susanna; Gambi, Ennio

    2018-05-29

    Fall detection is one of the most investigated themes in the research on assistive solutions for aged people. In particular, a false-alarm-free discrimination between falls and non-falls is indispensable, especially to assist elderly people living alone. Current technological solutions designed to monitor several types of activities in indoor environments can guarantee absolute privacy to the people that decide to rely on them. Devices integrating RGB and depth cameras, such as the Microsoft Kinect, can ensure privacy and anonymity, since the depth information is considered to extract only meaningful information from video streams. In this paper, we propose an accurate fall detection method investigating the depth frames of the human body using a single device in a top-view configuration, with the subjects located under the device inside a room. Features extracted from depth frames train a classifier based on a binary support vector machine learning algorithm. The dataset includes 32 falls and 8 activities considered for comparison, for a total of 800 sequences performed by 20 adults. The system showed an accuracy of 98.6% and only one false positive.

  4. Distributed Pedestrian Detection Alerts Based on Data Fusion with Accurate Localization

    Directory of Open Access Journals (Sweden)

    Arturo de la Escalera

    2013-09-01

    Full Text Available Among Advanced Driver Assistance Systems (ADAS pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided.

  5. Distributed pedestrian detection alerts based on data fusion with accurate localization.

    Science.gov (United States)

    García, Fernando; Jiménez, Felipe; Anaya, José Javier; Armingol, José María; Naranjo, José Eugenio; de la Escalera, Arturo

    2013-09-04

    Among Advanced Driver Assistance Systems (ADAS) pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner) and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided.

  6. Robust and Accurate Anomaly Detection in ECG Artifacts Using Time Series Motif Discovery

    Science.gov (United States)

    Sivaraks, Haemwaan

    2015-01-01

    Electrocardiogram (ECG) anomaly detection is an important technique for detecting dissimilar heartbeats which helps identify abnormal ECGs before the diagnosis process. Currently available ECG anomaly detection methods, ranging from academic research to commercial ECG machines, still suffer from a high false alarm rate because these methods are not able to differentiate ECG artifacts from real ECG signal, especially, in ECG artifacts that are similar to ECG signals in terms of shape and/or frequency. The problem leads to high vigilance for physicians and misinterpretation risk for nonspecialists. Therefore, this work proposes a novel anomaly detection technique that is highly robust and accurate in the presence of ECG artifacts which can effectively reduce the false alarm rate. Expert knowledge from cardiologists and motif discovery technique is utilized in our design. In addition, every step of the algorithm conforms to the interpretation of cardiologists. Our method can be utilized to both single-lead ECGs and multilead ECGs. Our experiment results on real ECG datasets are interpreted and evaluated by cardiologists. Our proposed algorithm can mostly achieve 100% of accuracy on detection (AoD), sensitivity, specificity, and positive predictive value with 0% false alarm rate. The results demonstrate that our proposed method is highly accurate and robust to artifacts, compared with competitive anomaly detection methods. PMID:25688284

  7. High accurate time system of the Low Latitude Meridian Circle.

    Science.gov (United States)

    Yang, Jing; Wang, Feng; Li, Zhiming

    In order to obtain the high accurate time signal for the Low Latitude Meridian Circle (LLMC), a new GPS accurate time system is developed which include GPS, 1 MC frequency source and self-made clock system. The second signal of GPS is synchronously used in the clock system and information can be collected by a computer automatically. The difficulty of the cancellation of the time keeper can be overcomed by using this system.

  8. Parkinsonian rest tremor can be detected accurately based on neuronal oscillations recorded from the subthalamic nucleus.

    Science.gov (United States)

    Hirschmann, J; Schoffelen, J M; Schnitzler, A; van Gerven, M A J

    2017-10-01

    To investigate the possibility of tremor detection based on deep brain activity. We re-analyzed recordings of local field potentials (LFPs) from the subthalamic nucleus in 10 PD patients (12 body sides) with spontaneously fluctuating rest tremor. Power in several frequency bands was estimated and used as input to Hidden Markov Models (HMMs) which classified short data segments as either tremor-free rest or rest tremor. HMMs were compared to direct threshold application to individual power features. Applying a threshold directly to band-limited power was insufficient for tremor detection (mean area under the curve [AUC] of receiver operating characteristic: 0.64, STD: 0.19). Multi-feature HMMs, in contrast, allowed for accurate detection (mean AUC: 0.82, STD: 0.15), using four power features obtained from a single contact pair. Within-patient training yielded better accuracy than across-patient training (0.84vs. 0.78, p=0.03), yet tremor could often be detected accurately with either approach. High frequency oscillations (>200Hz) were the best performing individual feature. LFP-based markers of tremor are robust enough to allow for accurate tremor detection in short data segments, provided that appropriate statistical models are used. LFP-based markers of tremor could be useful control signals for closed-loop deep brain stimulation. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  9. Fast and accurate spectral estimation for online detection of partial broken bar in induction motors

    Science.gov (United States)

    Samanta, Anik Kumar; Naha, Arunava; Routray, Aurobinda; Deb, Alok Kanti

    2018-01-01

    In this paper, an online and real-time system is presented for detecting partial broken rotor bar (BRB) of inverter-fed squirrel cage induction motors under light load condition. This system with minor modifications can detect any fault that affects the stator current. A fast and accurate spectral estimator based on the theory of Rayleigh quotient is proposed for detecting the spectral signature of BRB. The proposed spectral estimator can precisely determine the relative amplitude of fault sidebands and has low complexity compared to available high-resolution subspace-based spectral estimators. Detection of low-amplitude fault components has been improved by removing the high-amplitude fundamental frequency using an extended-Kalman based signal conditioner. Slip is estimated from the stator current spectrum for accurate localization of the fault component. Complexity and cost of sensors are minimal as only a single-phase stator current is required. The hardware implementation has been carried out on an Intel i7 based embedded target ported through the Simulink Real-Time. Evaluation of threshold and detectability of faults with different conditions of load and fault severity are carried out with empirical cumulative distribution function.

  10. An Accurate Framework for Arbitrary View Pedestrian Detection in Images

    Science.gov (United States)

    Fan, Y.; Wen, G.; Qiu, S.

    2018-01-01

    We consider the problem of detect pedestrian under from images collected under various viewpoints. This paper utilizes a novel framework called locality-constrained affine subspace coding (LASC). Firstly, the positive training samples are clustered into similar entities which represent similar viewpoint. Then Principal Component Analysis (PCA) is used to obtain the shared feature of each viewpoint. Finally, the samples that can be reconstructed by linear approximation using their top- k nearest shared feature with a small error are regarded as a correct detection. No negative samples are required for our method. Histograms of orientated gradient (HOG) features are used as the feature descriptors, and the sliding window scheme is adopted to detect humans in images. The proposed method exploits the sparse property of intrinsic information and the correlations among the multiple-views samples. Experimental results on the INRIA and SDL human datasets show that the proposed method achieves a higher performance than the state-of-the-art methods in form of effect and efficiency.

  11. A Highly Accurate Approach for Aeroelastic System with Hysteresis Nonlinearity

    Directory of Open Access Journals (Sweden)

    C. C. Cui

    2017-01-01

    Full Text Available We propose an accurate approach, based on the precise integration method, to solve the aeroelastic system of an airfoil with a pitch hysteresis. A major procedure for achieving high precision is to design a predictor-corrector algorithm. This algorithm enables accurate determination of switching points resulting from the hysteresis. Numerical examples show that the results obtained by the presented method are in excellent agreement with exact solutions. In addition, the high accuracy can be maintained as the time step increases in a reasonable range. It is also found that the Runge-Kutta method may sometimes provide quite different and even fallacious results, though the step length is much less than that adopted in the presented method. With such high computational accuracy, the presented method could be applicable in dynamical systems with hysteresis nonlinearities.

  12. Pink-Beam, Highly-Accurate Compact Water Cooled Slits

    International Nuclear Information System (INIS)

    Lyndaker, Aaron; Deyhim, Alex; Jayne, Richard; Waterman, Dave; Caletka, Dave; Steadman, Paul; Dhesi, Sarnjeet

    2007-01-01

    Advanced Design Consulting, Inc. (ADC) has designed accurate compact slits for applications where high precision is required. The system consists of vertical and horizontal slit mechanisms, a vacuum vessel which houses them, water cooling lines with vacuum guards connected to the individual blades, stepper motors with linear encoders, limit (home position) switches and electrical connections including internal wiring for a drain current measurement system. The total slit size is adjustable from 0 to 15 mm both vertically and horizontally. Each of the four blades are individually controlled and motorized. In this paper, a summary of the design and Finite Element Analysis of the system are presented

  13. Accurate Detection of Dysmorphic Nuclei Using Dynamic Programming and Supervised Classification.

    Science.gov (United States)

    Verschuuren, Marlies; De Vylder, Jonas; Catrysse, Hannes; Robijns, Joke; Philips, Wilfried; De Vos, Winnok H

    2017-01-01

    A vast array of pathologies is typified by the presence of nuclei with an abnormal morphology. Dysmorphic nuclear phenotypes feature dramatic size changes or foldings, but also entail much subtler deviations such as nuclear protrusions called blebs. Due to their unpredictable size, shape and intensity, dysmorphic nuclei are often not accurately detected in standard image analysis routines. To enable accurate detection of dysmorphic nuclei in confocal and widefield fluorescence microscopy images, we have developed an automated segmentation algorithm, called Blebbed Nuclei Detector (BleND), which relies on two-pass thresholding for initial nuclear contour detection, and an optimal path finding algorithm, based on dynamic programming, for refining these contours. Using a robust error metric, we show that our method matches manual segmentation in terms of precision and outperforms state-of-the-art nuclear segmentation methods. Its high performance allowed for building and integrating a robust classifier that recognizes dysmorphic nuclei with an accuracy above 95%. The combined segmentation-classification routine is bound to facilitate nucleus-based diagnostics and enable real-time recognition of dysmorphic nuclei in intelligent microscopy workflows.

  14. Accurate Detection of Dysmorphic Nuclei Using Dynamic Programming and Supervised Classification.

    Directory of Open Access Journals (Sweden)

    Marlies Verschuuren

    Full Text Available A vast array of pathologies is typified by the presence of nuclei with an abnormal morphology. Dysmorphic nuclear phenotypes feature dramatic size changes or foldings, but also entail much subtler deviations such as nuclear protrusions called blebs. Due to their unpredictable size, shape and intensity, dysmorphic nuclei are often not accurately detected in standard image analysis routines. To enable accurate detection of dysmorphic nuclei in confocal and widefield fluorescence microscopy images, we have developed an automated segmentation algorithm, called Blebbed Nuclei Detector (BleND, which relies on two-pass thresholding for initial nuclear contour detection, and an optimal path finding algorithm, based on dynamic programming, for refining these contours. Using a robust error metric, we show that our method matches manual segmentation in terms of precision and outperforms state-of-the-art nuclear segmentation methods. Its high performance allowed for building and integrating a robust classifier that recognizes dysmorphic nuclei with an accuracy above 95%. The combined segmentation-classification routine is bound to facilitate nucleus-based diagnostics and enable real-time recognition of dysmorphic nuclei in intelligent microscopy workflows.

  15. Parente2: a fast and accurate method for detecting identity by descent

    KAUST Repository

    Rodriguez, Jesse M.

    2014-10-01

    Identity-by-descent (IBD) inference is the problem of establishing a genetic connection between two individuals through a genomic segment that is inherited by both individuals from a recent common ancestor. IBD inference is an important preceding step in a variety of population genomic studies, ranging from demographic studies to linking genomic variation with phenotype and disease. The problem of accurate IBD detection has become increasingly challenging with the availability of large collections of human genotypes and genomes: Given a cohort\\'s size, a quadratic number of pairwise genome comparisons must be performed. Therefore, computation time and the false discovery rate can also scale quadratically. To enable accurate and efficient large-scale IBD detection, we present Parente2, a novel method for detecting IBD segments. Parente2 is based on an embedded log-likelihood ratio and uses a model that accounts for linkage disequilibrium by explicitly modeling haplotype frequencies. Parente2 operates directly on genotype data without the need to phase data prior to IBD inference. We evaluate Parente2\\'s performance through extensive simulations using real data, and we show that it provides substantially higher accuracy compared to previous state-of-the-art methods while maintaining high computational efficiency.

  16. Parente2: a fast and accurate method for detecting identity by descent

    KAUST Repository

    Rodriguez, Jesse M.; Bercovici, Sivan; Huang, Lin; Frostig, Roy; Batzoglou, Serafim

    2014-01-01

    Identity-by-descent (IBD) inference is the problem of establishing a genetic connection between two individuals through a genomic segment that is inherited by both individuals from a recent common ancestor. IBD inference is an important preceding step in a variety of population genomic studies, ranging from demographic studies to linking genomic variation with phenotype and disease. The problem of accurate IBD detection has become increasingly challenging with the availability of large collections of human genotypes and genomes: Given a cohort's size, a quadratic number of pairwise genome comparisons must be performed. Therefore, computation time and the false discovery rate can also scale quadratically. To enable accurate and efficient large-scale IBD detection, we present Parente2, a novel method for detecting IBD segments. Parente2 is based on an embedded log-likelihood ratio and uses a model that accounts for linkage disequilibrium by explicitly modeling haplotype frequencies. Parente2 operates directly on genotype data without the need to phase data prior to IBD inference. We evaluate Parente2's performance through extensive simulations using real data, and we show that it provides substantially higher accuracy compared to previous state-of-the-art methods while maintaining high computational efficiency.

  17. Atomic spectroscopy and highly accurate measurement: determination of fundamental constants

    International Nuclear Information System (INIS)

    Schwob, C.

    2006-12-01

    This document reviews the theoretical and experimental achievements of the author concerning highly accurate atomic spectroscopy applied for the determination of fundamental constants. A pure optical frequency measurement of the 2S-12D 2-photon transitions in atomic hydrogen and deuterium has been performed. The experimental setting-up is described as well as the data analysis. Optimized values for the Rydberg constant and Lamb shifts have been deduced (R = 109737.31568516 (84) cm -1 ). An experiment devoted to the determination of the fine structure constant with an aimed relative uncertainty of 10 -9 began in 1999. This experiment is based on the fact that Bloch oscillations in a frequency chirped optical lattice are a powerful tool to transfer coherently many photon momenta to the atoms. We have used this method to measure accurately the ratio h/m(Rb). The measured value of the fine structure constant is α -1 = 137.03599884 (91) with a relative uncertainty of 6.7*10 -9 . The future and perspectives of this experiment are presented. This document presented before an academic board will allow his author to manage research work and particularly to tutor thesis students. (A.C.)

  18. HIPPI: highly accurate protein family classification with ensembles of HMMs

    Directory of Open Access Journals (Sweden)

    Nam-phuong Nguyen

    2016-11-01

    Full Text Available Abstract Background Given a new biological sequence, detecting membership in a known family is a basic step in many bioinformatics analyses, with applications to protein structure and function prediction and metagenomic taxon identification and abundance profiling, among others. Yet family identification of sequences that are distantly related to sequences in public databases or that are fragmentary remains one of the more difficult analytical problems in bioinformatics. Results We present a new technique for family identification called HIPPI (Hierarchical Profile Hidden Markov Models for Protein family Identification. HIPPI uses a novel technique to represent a multiple sequence alignment for a given protein family or superfamily by an ensemble of profile hidden Markov models computed using HMMER. An evaluation of HIPPI on the Pfam database shows that HIPPI has better overall precision and recall than blastp, HMMER, and pipelines based on HHsearch, and maintains good accuracy even for fragmentary query sequences and for protein families with low average pairwise sequence identity, both conditions where other methods degrade in accuracy. Conclusion HIPPI provides accurate protein family identification and is robust to difficult model conditions. Our results, combined with observations from previous studies, show that ensembles of profile Hidden Markov models can better represent multiple sequence alignments than a single profile Hidden Markov model, and thus can improve downstream analyses for various bioinformatic tasks. Further research is needed to determine the best practices for building the ensemble of profile Hidden Markov models. HIPPI is available on GitHub at https://github.com/smirarab/sepp .

  19. Robust and accurate detection algorithm for multimode polymer optical FBG sensor system

    DEFF Research Database (Denmark)

    Ganziy, Denis; Jespersen, O.; Rose, B.

    2015-01-01

    We propose a novel dynamic gate algorithm (DGA) for robust and fast peak detection. The algorithm uses a threshold determined detection window and center of gravity algorithm with bias compensation. Our experiment demonstrates that the DGA method is fast and robust with better stability and accur...

  20. Highly Accurate Calculations of the Phase Diagram of Cold Lithium

    Science.gov (United States)

    Shulenburger, Luke; Baczewski, Andrew

    The phase diagram of lithium is particularly complicated, exhibiting many different solid phases under the modest application of pressure. Experimental efforts to identify these phases using diamond anvil cells have been complemented by ab initio theory, primarily using density functional theory (DFT). Due to the multiplicity of crystal structures whose enthalpy is nearly degenerate and the uncertainty introduced by density functional approximations, we apply the highly accurate many-body diffusion Monte Carlo (DMC) method to the study of the solid phases at low temperature. These calculations span many different phases, including several with low symmetry, demonstrating the viability of DMC as a method for calculating phase diagrams for complex solids. Our results can be used as a benchmark to test the accuracy of various density functionals. This can strengthen confidence in DFT based predictions of more complex phenomena such as the anomalous melting behavior predicted for lithium at high pressures. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. DOE's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  1. The place of highly accurate methods by RNAA in metrology

    International Nuclear Information System (INIS)

    Dybczynski, R.; Danko, B.; Polkowska-Motrenko, H.; Samczynski, Z.

    2006-01-01

    With the introduction of physical metrological concepts to chemical analysis which require that the result should be accompanied by uncertainty statement written down in terms of Sl units, several researchers started to consider lD-MS as the only method fulfilling this requirement. However, recent publications revealed that in certain cases also some expert laboratories using lD-MS and analyzing the same material, produced results for which their uncertainty statements did not overlap, what theoretically should not have taken place. This shows that no monopoly is good in science and it would be desirable to widen the set of methods acknowledged as primary in inorganic trace analysis. Moreover, lD-MS cannot be used for monoisotopic elements. The need for searching for other methods having similar metrological quality as the lD-MS seems obvious. In this paper, our long-time experience on devising highly accurate ('definitive') methods by RNAA for the determination of selected trace elements in biological materials is reviewed. The general idea of definitive methods based on combination of neutron activation with the highly selective and quantitative isolation of the indicator radionuclide by column chromatography followed by gamma spectrometric measurement is reminded and illustrated by examples of the performance of such methods when determining Cd, Co, Mo, etc. lt is demonstrated that such methods are able to provide very reliable results with very low levels of uncertainty traceable to Sl units

  2. Accurate calculation of high harmonics generated by relativistic Thomson scattering

    International Nuclear Information System (INIS)

    Popa, Alexandru

    2008-01-01

    The recent emergence of the field of ultraintense laser pulses, corresponding to beam intensities higher than 10 18 W cm -2 , brings about the problem of the high harmonic generation (HHG) by the relativistic Thomson scattering of the electromagnetic radiation by free electrons. Starting from the equations of the relativistic motion of the electron in the electromagnetic field, we give an exact solution of this problem. Taking into account the Lienard-Wiechert equations, we obtain a periodic scattered electromagnetic field. Without loss of generality, the solution is strongly simplified by observing that the electromagnetic field is always normal to the direction electron-detector. The Fourier series expansion of this field leads to accurate expressions of the high harmonics generated by the Thomson scattering. Our calculations lead to a discrete HHG spectrum, whose shape and angular distribution are in agreement with the experimental data from the literature. Since no approximations were made, our approach is also valid in the ultrarelativistic regime, corresponding to intensities higher than 10 23 W cm -2 , where it predicts a strong increase of the HHG intensities and of the order of harmonics. In this domain, the nonlinear Thomson scattering could be an efficient source of hard x-rays

  3. Ulysses: accurate detection of low-frequency structural variations in large insert-size sequencing libraries.

    Science.gov (United States)

    Gillet-Markowska, Alexandre; Richard, Hugues; Fischer, Gilles; Lafontaine, Ingrid

    2015-03-15

    The detection of structural variations (SVs) in short-range Paired-End (PE) libraries remains challenging because SV breakpoints can involve large dispersed repeated sequences, or carry inherent complexity, hardly resolvable with classical PE sequencing data. In contrast, large insert-size sequencing libraries (Mate-Pair libraries) provide higher physical coverage of the genome and give access to repeat-containing regions. They can thus theoretically overcome previous limitations as they are becoming routinely accessible. Nevertheless, broad insert size distributions and high rates of chimerical sequences are usually associated to this type of libraries, which makes the accurate annotation of SV challenging. Here, we present Ulysses, a tool that achieves drastically higher detection accuracy than existing tools, both on simulated and real mate-pair sequencing datasets from the 1000 Human Genome project. Ulysses achieves high specificity over the complete spectrum of variants by assessing, in a principled manner, the statistical significance of each possible variant (duplications, deletions, translocations, insertions and inversions) against an explicit model for the generation of experimental noise. This statistical model proves particularly useful for the detection of low frequency variants. SV detection performed on a large insert Mate-Pair library from a breast cancer sample revealed a high level of somatic duplications in the tumor and, to a lesser extent, in the blood sample as well. Altogether, these results show that Ulysses is a valuable tool for the characterization of somatic mosaicism in human tissues and in cancer genomes. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Highly accurate symplectic element based on two variational principles

    Science.gov (United States)

    Qing, Guanghui; Tian, Jia

    2018-02-01

    For the stability requirement of numerical resultants, the mathematical theory of classical mixed methods are relatively complex. However, generalized mixed methods are automatically stable, and their building process is simple and straightforward. In this paper, based on the seminal idea of the generalized mixed methods, a simple, stable, and highly accurate 8-node noncompatible symplectic element (NCSE8) was developed by the combination of the modified Hellinger-Reissner mixed variational principle and the minimum energy principle. To ensure the accuracy of in-plane stress results, a simultaneous equation approach was also suggested. Numerical experimentation shows that the accuracy of stress results of NCSE8 are nearly the same as that of displacement methods, and they are in good agreement with the exact solutions when the mesh is relatively fine. NCSE8 has advantages of the clearing concept, easy calculation by a finite element computer program, higher accuracy and wide applicability for various linear elasticity compressible and nearly incompressible material problems. It is possible that NCSE8 becomes even more advantageous for the fracture problems due to its better accuracy of stresses.

  5. Accurate Natural Trail Detection Using a Combination of a Deep Neural Network and Dynamic Programming.

    Science.gov (United States)

    Adhikari, Shyam Prasad; Yang, Changju; Slot, Krzysztof; Kim, Hyongsuk

    2018-01-10

    This paper presents a vision sensor-based solution to the challenging problem of detecting and following trails in highly unstructured natural environments like forests, rural areas and mountains, using a combination of a deep neural network and dynamic programming. The deep neural network (DNN) concept has recently emerged as a very effective tool for processing vision sensor signals. A patch-based DNN is trained with supervised data to classify fixed-size image patches into "trail" and "non-trail" categories, and reshaped to a fully convolutional architecture to produce trail segmentation map for arbitrary-sized input images. As trail and non-trail patches do not exhibit clearly defined shapes or forms, the patch-based classifier is prone to misclassification, and produces sub-optimal trail segmentation maps. Dynamic programming is introduced to find an optimal trail on the sub-optimal DNN output map. Experimental results showing accurate trail detection for real-world trail datasets captured with a head mounted vision system are presented.

  6. Functional neuroimaging of visuospatial working memory tasks enables accurate detection of attention deficit and hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Rubi Hammer

    2015-01-01

    Full Text Available Finding neurobiological markers for neurodevelopmental disorders, such as attention deficit and hyperactivity disorder (ADHD, is a major objective of clinicians and neuroscientists. We examined if functional Magnetic Resonance Imaging (fMRI data from a few distinct visuospatial working memory (VSWM tasks enables accurately detecting cases with ADHD. We tested 20 boys with ADHD combined type and 20 typically developed (TD boys in four VSWM tasks that differed in feedback availability (feedback, no-feedback and reward size (large, small. We used a multimodal analysis based on brain activity in 16 regions of interest, significantly activated or deactivated in the four VSWM tasks (based on the entire participants' sample. Dimensionality of the data was reduced into 10 principal components that were used as the input variables to a logistic regression classifier. fMRI data from the four VSWM tasks enabled a classification accuracy of 92.5%, with high predicted ADHD probability values for most clinical cases, and low predicted ADHD probabilities for most TDs. This accuracy level was higher than those achieved by using the fMRI data of any single task, or the respective behavioral data. This indicates that task-based fMRI data acquired while participants perform a few distinct VSWM tasks enables improved detection of clinical cases.

  7. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Science.gov (United States)

    Kawai, Nobuyuki; He, Hongshen

    2016-01-01

    Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish) under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise). We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  8. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kawai

    Full Text Available Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise. We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  9. High accurate volume holographic correlator with 4000 parallel correlation channels

    Science.gov (United States)

    Ni, Kai; Qu, Zongyao; Cao, Liangcai; Su, Ping; He, Qingsheng; Jin, Guofan

    2008-03-01

    Volume holographic correlator allows simultaneously calculate the two-dimensional inner product between the input image and each stored image. We have recently experimentally implemented in VHC 4000 parallel correlation channels with better than 98% output accuracy in a single location in a crystal. The speckle modulation is used to suppress the sidelobes of the correlation patterns, allowing more correlation spots to be contained in the output plane. A modified exposure schedule is designed to ensure the hologram in each channel with unity diffraction efficiency. In this schedule, a restricted coefficient was introduced into the original exposure schedule to solve the problem that the sensitivity and time constant of the crystal will change as a time function when in high-capacity storage. An interleaving method is proposed to improve the output accuracy. By unifying the distribution of the input and stored image patterns without changing the inner products between them, this method could eliminate the impact of correlation pattern variety on calculated inner product values. Moreover, by using this method, the maximum correlation spot size is reduced, which decreases the required minimum safe clearance between neighboring spots in the output plane, allowing more spots to be parallely detected without crosstalk. The experimental results are given and analyzed.

  10. A highly accurate method for determination of dissolved oxygen: Gravimetric Winkler method

    International Nuclear Information System (INIS)

    Helm, Irja; Jalukse, Lauri; Leito, Ivo

    2012-01-01

    Highlights: ► Probably the most accurate method available for dissolved oxygen concentration measurement was developed. ► Careful analysis of uncertainty sources was carried out and the method was optimized for minimizing all uncertainty sources as far as practical. ► This development enables more accurate calibration of dissolved oxygen sensors for routine analysis than has been possible before. - Abstract: A high-accuracy Winkler titration method has been developed for determination of dissolved oxygen concentration. Careful analysis of uncertainty sources relevant to the Winkler method was carried out and the method was optimized for minimizing all uncertainty sources as far as practical. The most important improvements were: gravimetric measurement of all solutions, pre-titration to minimize the effect of iodine volatilization, accurate amperometric end point detection and careful accounting for dissolved oxygen in the reagents. As a result, the developed method is possibly the most accurate method of determination of dissolved oxygen available. Depending on measurement conditions and on the dissolved oxygen concentration the combined standard uncertainties of the method are in the range of 0.012–0.018 mg dm −3 corresponding to the k = 2 expanded uncertainty in the range of 0.023–0.035 mg dm −3 (0.27–0.38%, relative). This development enables more accurate calibration of electrochemical and optical dissolved oxygen sensors for routine analysis than has been possible before.

  11. Accurate masking technology for high-resolution powder blasting

    Science.gov (United States)

    Pawlowski, Anne-Gabrielle; Sayah, Abdeljalil; Gijs, Martin A. M.

    2005-07-01

    We have combined eroding 10 µm diameter Al2O3 particles with a new masking technology to realize the smallest and most accurate possible structures by powder blasting. Our masking technology is based on the sequential combination of two polymers:(i) the brittle epoxy resin SU8 for its photosensitivity and (ii) the elastic and thermocurable poly-dimethylsiloxane for its large erosion resistance. We have micropatterned various types of structures with a minimum width of 20 µm for test structures with an aspect ratio of 1, and 50 µm for test structures with an aspect ratio of 2.

  12. Stable and high order accurate difference methods for the elastic wave equation in discontinuous media

    KAUST Repository

    Duru, Kenneth; Virta, Kristoffer

    2014-01-01

    to be discontinuous. The key feature is the highly accurate and provably stable treatment of interfaces where media discontinuities arise. We discretize in space using high order accurate finite difference schemes that satisfy the summation by parts rule. Conditions

  13. Accurate detection of carcinoma cells by use of a cell microarray chip.

    Directory of Open Access Journals (Sweden)

    Shohei Yamamura

    Full Text Available BACKGROUND: Accurate detection and analysis of circulating tumor cells plays an important role in the diagnosis and treatment of metastatic cancer treatment. METHODS AND FINDINGS: A cell microarray chip was used to detect spiked carcinoma cells among leukocytes. The chip, with 20,944 microchambers (105 µm width and 50 µm depth, was made from polystyrene; and the formation of monolayers of leukocytes in the microchambers was observed. Cultured human T lymphoblastoid leukemia (CCRF-CEM cells were used to examine the potential of the cell microarray chip for the detection of spiked carcinoma cells. A T lymphoblastoid leukemia suspension was dispersed on the chip surface, followed by 15 min standing to allow the leukocytes to settle down into the microchambers. Approximately 29 leukocytes were found in each microchamber when about 600,000 leukocytes in total were dispersed onto a cell microarray chip. Similarly, when leukocytes isolated from human whole blood were used, approximately 89 leukocytes entered each microchamber when about 1,800,000 leukocytes in total were placed onto the cell microarray chip. After washing the chip surface, PE-labeled anti-cytokeratin monoclonal antibody and APC-labeled anti-CD326 (EpCAM monoclonal antibody solution were dispersed onto the chip surface and allowed to react for 15 min; and then a microarray scanner was employed to detect any fluorescence-positive cells within 20 min. In the experiments using spiked carcinoma cells (NCI-H1650, 0.01 to 0.0001%, accurate detection of carcinoma cells was achieved with PE-labeled anti-cytokeratin monoclonal antibody. Furthermore, verification of carcinoma cells in the microchambers was performed by double staining with the above monoclonal antibodies. CONCLUSION: The potential application of the cell microarray chip for the detection of CTCs was shown, thus demonstrating accurate detection by double staining for cytokeratin and EpCAM at the single carcinoma cell level.

  14. Optimal pcr primers for rapid and accurate detection of Aspergillus flavus isolates.

    Science.gov (United States)

    Al-Shuhaib, Mohammed Baqur S; Albakri, Ali H; Alwan, Sabah H; Almandil, Noor B; AbdulAzeez, Sayed; Borgio, J Francis

    2018-03-01

    Aspergillus flavus is among the most devastating opportunistic pathogens of several food crops including rice, due to its high production of carcinogenic aflatoxins. The presence of these organisms in economically important rice strip farming is a serious food safety concern. Several polymerase chain reaction (PCR) primers have been designed to detect this species; however, a comparative assessment of their accuracy has not been conducted. This study aims to identify the optimal diagnostic PCR primers for the identification of A. flavus, among widely available primers. We isolated 122 A. flavus native isolates from randomly collected rice strips (N = 300). We identified 109 isolates to the genus level using universal fungal PCR primer pairs. Nine pairs of primers were examined for their PCR diagnostic specificity on the 109 isolates. FLA PCR was found to be the optimal PCR primer pair for specific identification of the native isolates, over aflP(1), aflM, aflA, aflD, aflP(3), aflP(2), and aflR. The PEP primer pair was found to be the most unsuitable for A. flavus identification. In conclusion, the present study indicates the powerful specificity of the FLA PCR primer over other commonly available diagnostic primers for accurate, rapid, and large-scale identification of A. flavus native isolates. This study provides the first simple, practical comparative guide to PCR-based screening of A. flavus infection in rice strips. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Comparison of methods for accurate end-point detection of potentiometric titrations

    International Nuclear Information System (INIS)

    Villela, R L A; Borges, P P; Vyskočil, L

    2015-01-01

    Detection of the end point in potentiometric titrations has wide application on experiments that demand very low measurement uncertainties mainly for certifying reference materials. Simulations of experimental coulometric titration data and consequential error analysis of the end-point values were conducted using a programming code. These simulations revealed that the Levenberg-Marquardt method is in general more accurate than the traditional second derivative technique used currently as end-point detection for potentiometric titrations. Performance of the methods will be compared and presented in this paper

  16. Comparison of methods for accurate end-point detection of potentiometric titrations

    Science.gov (United States)

    Villela, R. L. A.; Borges, P. P.; Vyskočil, L.

    2015-01-01

    Detection of the end point in potentiometric titrations has wide application on experiments that demand very low measurement uncertainties mainly for certifying reference materials. Simulations of experimental coulometric titration data and consequential error analysis of the end-point values were conducted using a programming code. These simulations revealed that the Levenberg-Marquardt method is in general more accurate than the traditional second derivative technique used currently as end-point detection for potentiometric titrations. Performance of the methods will be compared and presented in this paper.

  17. Spectroscopic Constants and Vibrational Frequencies for l-C3H+ and Isotopologues from Highly-Accurate Quartic Force Fields: The Detection of l-C3H+ in the Horsehead Nebula PDR Questioned

    Science.gov (United States)

    Huang, Xinchuan; Fortenberry, Ryan Clifton; Lee, Timothy J.

    2013-01-01

    Very recently, molecular rotational transitions observed in the photon-dominated region of the Horsehead nebula have been attributed to l-C3H+. In an effort to corroborate this finding, we employed state-of-the art and proven high-accuracy quantum chemical techniques to compute spectroscopic constants for this cation and its isotopologues. Even though the B rotational constant from the fit of the observed spectrum and our computations agree to within 20 MHz, a typical level of accuracy, the D rotational constant differs by more than 40%, while the H rotational constant differs by three orders of magnitude. With the likely errors in the rotational transition energies resulting from this difference in D on the order of 1 MHz for the lowest observed transition (J = 4 yields 3) and growing as J increases, the assignment of the observed rotational lines from the Horsehead nebula to l-C3H+ is questionable.

  18. A highly accurate benchmark for reactor point kinetics with feedback

    International Nuclear Information System (INIS)

    Ganapol, B. D.; Picca, P.

    2010-10-01

    This work apply the concept of convergence acceleration, also known as extrapolation, to find the solution to the reactor kinetics equations describing nuclear reactor transients. The method features simplicity in that an approximate finite difference formulation is constructed and converged to high accuracy from knowledge of how the error term behaves. Through Rom berg extrapolation, we demonstrate its high accuracy for a variety of imposed reactivity insertions found in the literature as well as nonlinear temperature and fission product feedback. A unique feature of the proposed method, called RKE/R(om berg) algorithm, is interval bisection to ensure high accuracy. (Author)

  19. Laser interference lithography with highly accurate interferometric alignment

    NARCIS (Netherlands)

    van Soest, Frank J.; van Wolferen, Hendricus A.G.M.; Hoekstra, Hugo; de Ridder, R.M.; Worhoff, Kerstin; Lambeck, Paul

    It is shown experimentally that in laser interference lithography, by using a reference grating, respective grating layers can be positioned with high relative accuracy. A 0.001 degree angular and a few nanometers lateral resolution have been demonstrated.

  20. Accurate SERS detection of malachite green in aquatic products on basis of graphene wrapped flexible sensor.

    Science.gov (United States)

    Ouyang, Lei; Yao, Ling; Zhou, Taohong; Zhu, Lihua

    2018-10-16

    Malachite Green (MG) is a banned pesticide for aquaculture products. As a required inspection item, its fast and accurate determination before the products' accessing market is very important. Surface enhanced Raman scattering (SERS) is a promising tool for MG sensing, but it requires the overcoming of several problems such as fairly poor sensitivity and reproducibility, especially laser induced chemical conversion and photo-bleaching during SERS observation. By using a graphene wrapped Ag array based flexible membrane sensor, a modified SERS strategy was proposed for the sensitive and accurate detection of MG. The graphene layer functioned as an inert protector for impeding chemical transferring of the bioproduct Leucomalachite Green (LMG) to MG during the SERS detection, and as a heat transmitter for preventing laser induced photo-bleaching, which enables the separate detection of MG and LMG in fish extracts. The combination of the Ag array and the graphene cover also produced plentiful densely and uniformly distributed hot spots, leading to analytical enhancement factor up to 3.9 × 10 8 and excellent reproducibility (relative standard deviation low to 5.8% for 70 runs). The proposed method was easily used for MG detection with limit of detection (LOD) as low as 2.7 × 10 -11  mol L -1 . The flexibility of the sensor enable it have a merit for in-field fast detection of MG residues on the scale of a living fish through a surface extraction and paste transferring manner. The developed strategy was successfully applied in the analysis of real samples, showing good prospects for both the fast inspection and quantitative detection of MG. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. A new diagnostic tool for rapid and accurate detection of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Ali Nour-Neamatollahi

    2018-03-01

    Full Text Available Mycobacterium tuberculosis, acid fast bacilli from the family of Mycobacteriaceae, is the causative agent of most cases of tuberculosis. Tuberculosis, as a communicable disease, remains a serious public health threat, killing more than one million people globally every year. Primary diagnosis of tuberculosis bacilli (TB relies mainly on microscopic detection of acid fast bacilli (AFB, but the method suffers from low sensitivity and the results largely depend on the technician’s skill. New diagnostic tools are necessary to be introduced for rapid and accurate detection of the bacilli in sputum samples. We, in collaboration with Anda Biologicals, have developed a new platform, named as “Patho-tb”, for rapid detection of AFB with high sensitivity and with low dependence on human skills. Evaluation of Patho-tb test performance was done in two settings: (1 primary field study conducted using 38 sputa from high TB prevalence area of Iran (Zabol city near to the Afghanistan border, and (2 main study conducted using 476 sputa from Tehran, capital of Iran. Patho-tb was applied for processed sputum samples in parallel with routine diagnostic methods (including AFB microscopy, culture and PCR. All test results were compared to final clinical diagnostic state of an individual and diagnostic sensitivity (DSe, specificity, positive predictive value, negative predictive value and accuracy of each test results were calculated using standard formulations. Analytical sensitivity and specificity of the Patho-tb test were also determined. Calculated values for five above mentioned parameters are as follows: for field study: AFB (DSe: 29.6, DSp: 81.8, PPV: 80, NPV: 23.1, AC: 44.7, Patho-tb (DSe: 63, DSp: 72.7, PPV: 85, NPV: 44.4, AC: 65.8, and for main study: AFB (DSe: 86.1, DSp: 99.4, PPV: 98.5, NPV: 93.9, AC: 95.2, Patho-tb (DSe: 97.4, DSp: 92.9, PPV: 86.5, NPV: 98.7, AC: 94.3. Reproducibility of Patho-tb test results were near to 100% (Cohen’s kappa value

  2. A simple and accurate onset detection method for a measured bell-shaped speed profile

    Directory of Open Access Journals (Sweden)

    Lior Botzer

    2009-06-01

    Full Text Available Motor control neuroscientists measure limb trajectories and extract the onset of the movement for a variety of purposes. Such trajectories are often aligned relative to the onset of individual movement before the features of that movement are extracted and their properties are inspected. Onset detection is performed either manually or automatically, typically by selecting a velocity threshold. Here, we present a simple onset detection algorithm that is more accurate than the conventional velocity threshold technique. The proposed method is based on a simple regression and follows the minimum acceleration with constraints model, in which the initial phase of the bell-shaped movement is modeled by a cubic power of the time. We demonstrate the performance of the suggested method and compare it to the velocity threshold technique and to manual onset detection by a group of motor control experts. The database for this comparison consists of simulated minimum jerk trajectories and recorded reaching movements.

  3. SpotCaliper: fast wavelet-based spot detection with accurate size estimation.

    Science.gov (United States)

    Püspöki, Zsuzsanna; Sage, Daniel; Ward, John Paul; Unser, Michael

    2016-04-15

    SpotCaliper is a novel wavelet-based image-analysis software providing a fast automatic detection scheme for circular patterns (spots), combined with the precise estimation of their size. It is implemented as an ImageJ plugin with a friendly user interface. The user is allowed to edit the results by modifying the measurements (in a semi-automated way), extract data for further analysis. The fine tuning of the detections includes the possibility of adjusting or removing the original detections, as well as adding further spots. The main advantage of the software is its ability to capture the size of spots in a fast and accurate way. http://bigwww.epfl.ch/algorithms/spotcaliper/ zsuzsanna.puspoki@epfl.ch Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Highly Accurate Timestamping for Ethernet-Based Clock Synchronization

    OpenAIRE

    Loschmidt, Patrick; Exel, Reinhard; Gaderer, Georg

    2012-01-01

    It is not only for test and measurement of great importance to synchronize clocks of networked devices to timely coordinate data acquisition. In this context the seek for high accuracy in Ethernet-based clock synchronization has been significantly supported by enhancements to the Network Time Protocol (NTP) and the introduction of the Precision Time Protocol (PTP). The latter was even applied to instrumentation and measurement applications through the introduction of LXI....

  5. Highly accurate photogrammetric measurements of the Planck reflectors

    Science.gov (United States)

    Amiri Parian, Jafar; Gruen, Armin; Cozzani, Alessandro

    2017-11-01

    The Planck mission of the European Space Agency (ESA) is designed to image the anisotropies of the Cosmic Background Radiation Field over the whole sky. To achieve this aim, sophisticated reflectors are used as part of the Planck telescope receiving system. The system consists of secondary and primary reflectors which are sections of two different ellipsoids of revolution with mean diameters of 1 and 1.6 meters. Deformations of the reflectors which influence the optical parameters and the gain of receiving signals are investigated in vacuum and at very low temperatures. For this investigation, among the various high accuracy measurement techniques, photogrammetry was selected. With respect to the photogrammetric measurements, special considerations had to be taken into account in design steps, measurement arrangement and data processing to achieve very high accuracies. The determinability of additional parameters of the camera under the given network configuration, datum definition, reliability and precision issues as well as workspace limits and propagating errors from different sources are considered. We have designed an optimal photogrammetric network by heuristic simulation for the flight model of the primary and the secondary reflectors with relative precisions better than 1:1000'000 and 1:400'000 to achieve the requested accuracies. A least squares best fit ellipsoid method was developed to determine the optical parameters of the reflectors. In this paper we will report about the procedures, the network design and the results of real measurements.

  6. Accurate Classification of Protein Subcellular Localization from High-Throughput Microscopy Images Using Deep Learning

    Directory of Open Access Journals (Sweden)

    Tanel Pärnamaa

    2017-05-01

    Full Text Available High-throughput microscopy of many single cells generates high-dimensional data that are far from straightforward to analyze. One important problem is automatically detecting the cellular compartment where a fluorescently-tagged protein resides, a task relatively simple for an experienced human, but difficult to automate on a computer. Here, we train an 11-layer neural network on data from mapping thousands of yeast proteins, achieving per cell localization classification accuracy of 91%, and per protein accuracy of 99% on held-out images. We confirm that low-level network features correspond to basic image characteristics, while deeper layers separate localization classes. Using this network as a feature calculator, we train standard classifiers that assign proteins to previously unseen compartments after observing only a small number of training examples. Our results are the most accurate subcellular localization classifications to date, and demonstrate the usefulness of deep learning for high-throughput microscopy.

  7. Accurate Classification of Protein Subcellular Localization from High-Throughput Microscopy Images Using Deep Learning.

    Science.gov (United States)

    Pärnamaa, Tanel; Parts, Leopold

    2017-05-05

    High-throughput microscopy of many single cells generates high-dimensional data that are far from straightforward to analyze. One important problem is automatically detecting the cellular compartment where a fluorescently-tagged protein resides, a task relatively simple for an experienced human, but difficult to automate on a computer. Here, we train an 11-layer neural network on data from mapping thousands of yeast proteins, achieving per cell localization classification accuracy of 91%, and per protein accuracy of 99% on held-out images. We confirm that low-level network features correspond to basic image characteristics, while deeper layers separate localization classes. Using this network as a feature calculator, we train standard classifiers that assign proteins to previously unseen compartments after observing only a small number of training examples. Our results are the most accurate subcellular localization classifications to date, and demonstrate the usefulness of deep learning for high-throughput microscopy. Copyright © 2017 Parnamaa and Parts.

  8. High-speed photography of dynamic photoelastic experiment with a highly accurate blasting machine

    Science.gov (United States)

    Katsuyama, Kunihisa; Ogata, Yuji; Wada, Yuji; Hashizume, K.

    1995-05-01

    A high accurate blasting machine which could control 1 microsecond(s) was developed. At first, explosion of a bridge wire in an electric detonator was observed and next the detonations of caps were observed with a high speed camera. It is well known that a compressed stress wave reflects at the free face, it propagates to the backward as a tensile stress wave, and cracks grow when the tensile stress becomes the dynamic tensile strength. The behavior of these cracks has been discussed through the observation of the dynamic photoelastic high speed photography and the three dimensional dynamic stress analysis.

  9. A simplified and accurate detection of the genetically modified wheat MON71800 with one calibrator plasmid.

    Science.gov (United States)

    Kim, Jae-Hwan; Park, Saet-Byul; Roh, Hyo-Jeong; Park, Sunghoon; Shin, Min-Ki; Moon, Gui Im; Hong, Jin-Hwan; Kim, Hae-Yeong

    2015-06-01

    With the increasing number of genetically modified (GM) events, unauthorized GMO releases into the food market have increased dramatically, and many countries have developed detection tools for them. This study described the qualitative and quantitative detection methods of unauthorized the GM wheat MON71800 with a reference plasmid (pGEM-M71800). The wheat acetyl-CoA carboxylase (acc) gene was used as the endogenous gene. The plasmid pGEM-M71800, which contains both the acc gene and the event-specific target MON71800, was constructed as a positive control for the qualitative and quantitative analyses. The limit of detection in the qualitative PCR assay was approximately 10 copies. In the quantitative PCR assay, the standard deviation and relative standard deviation repeatability values ranged from 0.06 to 0.25 and from 0.23% to 1.12%, respectively. This study supplies a powerful and very simple but accurate detection strategy for unauthorized GM wheat MON71800 that utilizes a single calibrator plasmid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Lung ultrasound accurately detects pneumothorax in a preterm newborn lamb model.

    Science.gov (United States)

    Blank, Douglas A; Hooper, Stuart B; Binder-Heschl, Corinna; Kluckow, Martin; Gill, Andrew W; LaRosa, Domenic A; Inocencio, Ishmael M; Moxham, Alison; Rodgers, Karyn; Zahra, Valerie A; Davis, Peter G; Polglase, Graeme R

    2016-06-01

    Pneumothorax is a common emergency affecting extremely preterm. In adult studies, lung ultrasound has performed better than chest x-ray in the diagnosis of pneumothorax. The purpose of this study was to determine the efficacy of lung ultrasound (LUS) examination to detect pneumothorax using a preterm animal model. This was a prospective, observational study using newborn Border-Leicester lambs at gestational age = 126 days (equivalent to gestational age = 26 weeks in humans) receiving mechanical ventilation from birth to 2 h of life. At the conclusion of the experiment, LUS was performed, the lambs were then euthanised and a post-mortem exam was immediately performed. We used previously published ultrasound techniques to identify pneumothorax. Test characteristics of LUS to detect pneumothorax were calculated, using the post-mortem exam as the 'gold standard' test. Nine lambs (18 lungs) were examined. Four lambs had a unilateral pneumothorax, all of which were identified by LUS with no false positives. This was the first study to use post-mortem findings to test the efficacy of LUS to detect pneumothorax in a newborn animal model. Lung ultrasound accurately detected pneumothorax, verified by post-mortem exam, in premature, newborn lambs. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  11. Extraordinary tunable dynamic range of electrochemical aptasensor for accurate detection of ochratoxin A in food samples

    Directory of Open Access Journals (Sweden)

    Lin Cheng

    2017-06-01

    Full Text Available We report the design of a sensitive, electrochemical aptasensor for detection of ochratoxin A (OTA with an extraordinary tunable dynamic sensing range. This electrochemical aptasensor is constructed based on the target induced aptamer-folding detection mechanism and the recognition between OTA and its aptamers results in the conformational change of the aptamer probe and thus signal changes for measurement. The dynamic sensing range of the electrochemical aptasensor is successfully tuned by introduction of free assistant aptamer probes in the sensing system. Our electrochemical aptasensor shows an extraordinary dynamic sensing range of 11-order magnitude of OTA concentration from 10−8 to 102 ng/g. Of great significance, the signal response in all OTA concentration ranges is at the same current scale, demonstrating that our sensing protocol in this research could be applied for accurate detections of OTA in a broad range without using any complicated treatment of signal amplification. Finally, OTA spiked red wine and maize samples in different dynamic sensing ranges are determined with the electrochemical aptasensor under optimized sensing conditions. This tuning strategy of dynamic sensing range may offer a promising platform for electrochemical aptasensor optimizations in practical applications.

  12. Reproducible Molecularly Imprinted Piezoelectric Sensor for Accurate and Sensitive Detection of Ractopamine in Swine and Feed Products

    Directory of Open Access Journals (Sweden)

    Mingfei Pan

    2018-06-01

    Full Text Available This paper describes the development of a reproducible molecularly imprinted piezoelectric sensor for the accurate and sensitive detection of ractopamine (RAC in swine and feed products. The synthesized molecularly imprinted polymer (MIP was directly immobilized on the surface of a quartz crystal microbalance (QCM Au chip as the recognition element. The experimental parameters in the fabrication, measurement and regeneration process were evaluated in detail to produce an MIP-based piezoelectric sensor with high sensing capability. The developed piezoelectric sensor was verified to perform favorably in the RAC analysis of swine and feed products, with acceptable accuracy (recovery: 75.9–93.3%, precision [relative standard deviation (n = 3: 2.3–6.4%], and sensitivity [limit of detection: 0.46 ng g−1 (swine and 0.38 ng g−1 (feed]. This portable MIP-based chip for the piezoelectric sensing of RAC could be reused for at least 30 cycles and easily stored for a long time. These results demonstrated that the developed MIP-based piezoelectric sensor presents an accurate, sensitive and cost-effective method for the quantitative detection of RAC in complex samples. This research offers a promising strategy for the development of novel effective devices used for use in food safety analysis.

  13. Accurate detection of hierarchical communities in complex networks based on nonlinear dynamical evolution

    Science.gov (United States)

    Zhuo, Zhao; Cai, Shi-Min; Tang, Ming; Lai, Ying-Cheng

    2018-04-01

    One of the most challenging problems in network science is to accurately detect communities at distinct hierarchical scales. Most existing methods are based on structural analysis and manipulation, which are NP-hard. We articulate an alternative, dynamical evolution-based approach to the problem. The basic principle is to computationally implement a nonlinear dynamical process on all nodes in the network with a general coupling scheme, creating a networked dynamical system. Under a proper system setting and with an adjustable control parameter, the community structure of the network would "come out" or emerge naturally from the dynamical evolution of the system. As the control parameter is systematically varied, the community hierarchies at different scales can be revealed. As a concrete example of this general principle, we exploit clustered synchronization as a dynamical mechanism through which the hierarchical community structure can be uncovered. In particular, for quite arbitrary choices of the nonlinear nodal dynamics and coupling scheme, decreasing the coupling parameter from the global synchronization regime, in which the dynamical states of all nodes are perfectly synchronized, can lead to a weaker type of synchronization organized as clusters. We demonstrate the existence of optimal choices of the coupling parameter for which the synchronization clusters encode accurate information about the hierarchical community structure of the network. We test and validate our method using a standard class of benchmark modular networks with two distinct hierarchies of communities and a number of empirical networks arising from the real world. Our method is computationally extremely efficient, eliminating completely the NP-hard difficulty associated with previous methods. The basic principle of exploiting dynamical evolution to uncover hidden community organizations at different scales represents a "game-change" type of approach to addressing the problem of community

  14. Tissue resonance interaction accurately detects colon lesions: A double-blind pilot study.

    Science.gov (United States)

    Dore, Maria P; Tufano, Marcello O; Pes, Giovanni M; Cuccu, Marianna; Farina, Valentina; Manca, Alessandra; Graham, David Y

    2015-07-07

    To investigated the performance of the tissue resonance interaction method (TRIM) for the non-invasive detection of colon lesions. We performed a prospective single-center blinded pilot study of consecutive adults undergoing colonoscopy at the University Hospital in Sassari, Italy. Before patients underwent colonoscopy, they were examined by the TRIMprobe which detects differences in electromagnetic properties between pathological and normal tissues. All patients had completed the polyethylene glycol-containing bowel prep for the colonoscopy procedure before being screened. During the procedure the subjects remained fully dressed. A hand-held probe was moved over the abdomen and variations in electromagnetic signals were recorded for 3 spectral lines (462-465 MHz, 930 MHz, and 1395 MHz). A single investigator, blind to any clinical information, performed the test using the TRIMprob system. Abnormal signals were identified and recorded as malignant or benign (adenoma or hyperplastic polyps). Findings were compared with those from colonoscopy with histologic confirmation. Statistical analysis was performed by χ(2) test. A total of 305 consecutive patients fulfilling the inclusion criteria were enrolled over a period of 12 months. The most frequent indication for colonoscopy was abdominal pain (33%). The TRIMprob was well accepted by all patients; none spontaneously complained about the procedure, and no adverse effects were observed. TRIM proved inaccurate for polyp detection in patients with inflammatory bowel disease (IBD) and they were excluded leaving 281 subjects (mean age 59 ± 13 years; 107 males). The TRIM detected and accurately characterized all 12 adenocarcinomas and 135/137 polyps (98.5%) including 64 adenomatous (100%) found. The method identified cancers and polyps with 98.7% sensitivity, 96.2% specificity, and 97.5% diagnostic accuracy, compared to colonoscopy and histology analyses. The positive predictive value was 96.7% and the negative predictive

  15. Photogrammetry: an accurate and reliable tool to detect thoracic musculoskeletal abnormalities in preterm infants.

    Science.gov (United States)

    Davidson, Josy; dos Santos, Amelia Miyashiro N; Garcia, Kessey Maria B; Yi, Liu C; João, Priscila C; Miyoshi, Milton H; Goulart, Ana Lucia

    2012-09-01

    To analyse the accuracy and reproducibility of photogrammetry in detecting thoracic abnormalities in infants born prematurely. Cross-sectional study. The Premature Clinic at the Federal University of São Paolo. Fifty-eight infants born prematurely in their first year of life. Measurement of the manubrium/acromion/trapezius angle (degrees) and the deepest thoracic retraction (cm). Digitised photographs were analysed by two blinded physiotherapists using a computer program (SAPO; http://SAPO.incubadora.fapesp.br) to detect shoulder elevation and thoracic retraction. Physical examinations performed independently by two physiotherapists were used to assess the accuracy of the new tool. Thoracic alterations were detected in 39 (67%) and in 40 (69%) infants by Physiotherapists 1 and 2, respectively (kappa coefficient=0.80). Using a receiver operating characteristic curve, measurement of the manubrium/acromion/trapezius angle and the deepest thoracic retraction indicated accuracy of 0.79 and 0.91, respectively. For measurement of the manubrium/acromion/trapezius angle, the Bland and Altman limits of agreement were -6.22 to 7.22° [mean difference (d)=0.5] for repeated measures by one physiotherapist, and -5.29 to 5.79° (d=0.75) between two physiotherapists. For thoracic retraction, the intra-rater limits of agreement were -0.14 to 0.18cm (d=0.02) and the inter-rater limits of agreement were -0.20 to -0.17cm (d=0.02). SAPO provided an accurate and reliable tool for the detection of thoracic abnormalities in preterm infants. Copyright © 2011 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  16. High Speed Edge Detection

    Science.gov (United States)

    Prokop, Norman F (Inventor)

    2016-01-01

    Analog circuits for detecting edges in pixel arrays are disclosed. A comparator may be configured to receive an all pass signal and a low pass signal for a pixel intensity in an array of pixels. A latch may be configured to receive a counter signal and a latching signal from the comparator. The comparator may be configured to send the latching signal to the latch when the all pass signal is below the low pass signal minus an offset. The latch may be configured to hold a last negative edge location when the latching signal is received from the comparator.

  17. A very accurate method for sentinel lymph node investigation: Gamma detecting probe associated with SPECT examination for depth

    International Nuclear Information System (INIS)

    Ascoli, G.; Cinti, P.; Nonni, M.; Rossi, B.

    2002-01-01

    Aim: aim of this study is to magnify the lymphoscintigraphy examination by gamma probe with SPECT acquisition for very accurate detection of depth of axilla node in patients affected by melanoma. Methods: according to physiological peculiarities the lymphatic system plays a very important role and represents the most important barrier to neoplastic cells spreading. The 'sentinel node' is the first lymph node draining the affected area. The tendency for surgery is a 'preventive' axillary dissection, even in presence of a clinically negative examination. In fact a high percentage of clinically negative lymph node shows a positive histology (presence of metastatic cells). The nuclear medicine method for researching 'sentinel node' is represented by a regional lymphoscintigraphy with normal gamma camera with a large field of view followed by examination with gamma detecting probe and, in following day, controlled in operating room to confirm the presence of the node early identified. We have completed this protocol with SPECT examination of affected axilla by use of injected laboratory capillary around axilla to perform an exact investigation of node depth. Discussion: Our experience in 150 cases in 18 months shows 100% of axilla 'sentinel node' detection, 25 cases with positive histologic examination and subsequently axillary dissection. Conclusions: In conclusion the scintigraphic examination with lymphoscintigraphy represents a good tool for management of patient with melanoma and the use of ''targeting' with collimated SPECT represent a very aid for the surgeon in reduction time for detection and dissection of lymph node, with high reduction of anesthesia duration

  18. Accurate method for luminous transmittance and signal detection quotients measurements in sunglasses lenses

    Science.gov (United States)

    Loureiro, A. D.; Gomes, L. M.; Ventura, L.

    2018-02-01

    The international standard ISO 12312-1 proposes transmittance tests that quantify how dark sunglasses lenses are and whether or not they are suitable for driving. To perform these tests a spectrometer is required. In this study, we present and analyze theoretically an accurate alternative method for performing these measurements using simple components. Using three LEDs and a four-channel sensor we generated weighting functions similar to the standard ones for luminous and traffic lights transmittances. From 89 sunglasses lens spectroscopy data, we calculated luminous transmittance and signal detection quotients using our obtained weighting functions and the standard ones. Mean-difference Tukey plots were used to compare the results. All tested sunglasses lenses were classified in the right category and correctly as suitable or not for driving. The greatest absolute errors for luminous transmittance and red, yellow, green and blue signal detection quotients were 0.15%, 0.17, 0.06, 0.04 and 0.18, respectively. This method will be used in a device capable to perform transmittance tests (visible, traffic lights and ultraviolet (UV)) according to the standard. It is important to measure rightly luminous transmittance and relative visual attenuation quotients to report correctly whether or not sunglasses are suitable for driving. Moreover, standard UV requirements depend on luminous transmittance.

  19. SV2: accurate structural variation genotyping and de novo mutation detection from whole genomes.

    Science.gov (United States)

    Antaki, Danny; Brandler, William M; Sebat, Jonathan

    2018-05-15

    Structural variation (SV) detection from short-read whole genome sequencing is error prone, presenting significant challenges for population or family-based studies of disease. Here, we describe SV2, a machine-learning algorithm for genotyping deletions and duplications from paired-end sequencing data. SV2 can rapidly integrate variant calls from multiple structural variant discovery algorithms into a unified call set with high genotyping accuracy and capability to detect de novo mutations. SV2 is freely available on GitHub (https://github.com/dantaki/SV2). jsebat@ucsd.edu. Supplementary data are available at Bioinformatics online.

  20. [Detecting high risk pregnancy].

    Science.gov (United States)

    Doret, Muriel; Gaucherand, Pascal

    2009-12-20

    Antenatal care is aiming to reduce maternal land foetal mortality and morbidity. Maternal and foetal mortality can be due to different causes. Their knowledge allows identifying pregnancy (high risk pregnancy) with factors associated with an increased risk for maternal and/or foetal mortality and serious morbidity. Identification of high risk pregnancies and initiation of appropriate treatment and/or surveillance should improve maternal and/or foetal outcome. New risk factors are continuously described thanks to improvement in antenatal care and development in biology and cytopathology, increasing complexity in identifying high risk pregnancies. Level of risk can change all over the pregnancy. Ideally, it should be evaluated prior to the pregnancy and at each antenatal visit. Clinical examination is able to screen for intra-uterin growth restriction, pre-eclampsia, threatened for preterm labour; ultrasounds help in the diagnosis of foetal morphological anomalies, foetal chromosomal anomalies, placenta praevia and abnormal foetal growth; biological exams are used to screen for pre-eclampsia, gestational diabetes, trisomy 21 (for which screening method just changed), rhesus immunisation, seroconversion for toxoplasmosis or rubeola, unknown infectious disease (syphilis, hepatitis B, VIH). During pregnancy, most of the preventive strategies have to be initiated during the first trimester or even before conception. Prevention for neural-tube defects, neonatal hypocalcemia and listeriosis should be performed for all women. On the opposite, some measures are concerning only women with risk factors such as prevention for toxoplasmosis, rhesus immunization (which recently changed), tobacco complications and pre-eclampsia and intra-uterine growth factor restriction.

  1. Accurate Sybil Attack Detection Based on Fine-Grained Physical Channel Information

    Directory of Open Access Journals (Sweden)

    Chundong Wang

    2018-03-01

    Full Text Available With the development of the Internet-of-Things (IoT, wireless network security has more and more attention paid to it. The Sybil attack is one of the famous wireless attacks that can forge wireless devices to steal information from clients. These forged devices may constantly attack target access points to crush the wireless network. In this paper, we propose a novel Sybil attack detection based on Channel State Information (CSI. This detection algorithm can tell whether the static devices are Sybil attackers by combining a self-adaptive multiple signal classification algorithm with the Received Signal Strength Indicator (RSSI. Moreover, we develop a novel tracing scheme to cluster the channel characteristics of mobile devices and detect dynamic attackers that change their channel characteristics in an error area. Finally, we experiment on mobile and commercial WiFi devices. Our algorithm can effectively distinguish the Sybil devices. The experimental results show that our Sybil attack detection system achieves high accuracy for both static and dynamic scenarios. Therefore, combining the phase and similarity of channel features, the multi-dimensional analysis of CSI can effectively detect Sybil nodes and improve the security of wireless networks.

  2. Accurate Sybil Attack Detection Based on Fine-Grained Physical Channel Information.

    Science.gov (United States)

    Wang, Chundong; Zhu, Likun; Gong, Liangyi; Zhao, Zhentang; Yang, Lei; Liu, Zheli; Cheng, Xiaochun

    2018-03-15

    With the development of the Internet-of-Things (IoT), wireless network security has more and more attention paid to it. The Sybil attack is one of the famous wireless attacks that can forge wireless devices to steal information from clients. These forged devices may constantly attack target access points to crush the wireless network. In this paper, we propose a novel Sybil attack detection based on Channel State Information (CSI). This detection algorithm can tell whether the static devices are Sybil attackers by combining a self-adaptive multiple signal classification algorithm with the Received Signal Strength Indicator (RSSI). Moreover, we develop a novel tracing scheme to cluster the channel characteristics of mobile devices and detect dynamic attackers that change their channel characteristics in an error area. Finally, we experiment on mobile and commercial WiFi devices. Our algorithm can effectively distinguish the Sybil devices. The experimental results show that our Sybil attack detection system achieves high accuracy for both static and dynamic scenarios. Therefore, combining the phase and similarity of channel features, the multi-dimensional analysis of CSI can effectively detect Sybil nodes and improve the security of wireless networks.

  3. Accurate Modeling of The Siemens S7 SCADA Protocol For Intrusion Detection And Digital Forensic

    Directory of Open Access Journals (Sweden)

    Amit Kleinmann

    2014-09-01

    Full Text Available The Siemens S7 protocol is commonly used in SCADA systems for communications between a Human Machine Interface (HMI and the Programmable Logic Controllers (PLCs. This paper presents a model-based Intrusion Detection Systems (IDS designed for S7 networks. The approach is based on the key observation that S7 traffic to and from a specific PLC is highly periodic; as a result, each HMI-PLC channel can be modeled using its own unique Deterministic Finite Automaton (DFA. The resulting DFA-based IDS is very sensitive and is able to flag anomalies such as a message appearing out of its position in the normal sequence or a message referring to a single unexpected bit. The intrusion detection approach was evaluated on traffic from two production systems. Despite its high sensitivity, the system had a very low false positive rate - over 99.82% of the traffic was identified as normal.

  4. LocARNA-P: Accurate boundary prediction and improved detection of structural RNAs

    DEFF Research Database (Denmark)

    Will, Sebastian; Joshi, Tejal; Hofacker, Ivo L.

    2012-01-01

    Current genomic screens for noncoding RNAs (ncRNAs) predict a large number of genomic regions containing potential structural ncRNAs. The analysis of these data requires highly accurate prediction of ncRNA boundaries and discrimination of promising candidate ncRNAs from weak predictions. Existing...... methods struggle with these goals because they rely on sequence-based multiple sequence alignments, which regularly misalign RNA structure and therefore do not support identification of structural similarities. To overcome this limitation, we compute columnwise and global reliabilities of alignments based...... on sequence and structure similarity; we refer to these structure-based alignment reliabilities as STARs. The columnwise STARs of alignments, or STAR profiles, provide a versatile tool for the manual and automatic analysis of ncRNAs. In particular, we improve the boundary prediction of the widely used nc...

  5. An Integrated GNSS/INS/LiDAR-SLAM Positioning Method for Highly Accurate Forest Stem Mapping

    Directory of Open Access Journals (Sweden)

    Chuang Qian

    2016-12-01

    Full Text Available Forest mapping, one of the main components of performing a forest inventory, is an important driving force in the development of laser scanning. Mobile laser scanning (MLS, in which laser scanners are installed on moving platforms, has been studied as a convenient measurement method for forest mapping in the past several years. Positioning and attitude accuracies are important for forest mapping using MLS systems. Inertial Navigation Systems (INSs and Global Navigation Satellite Systems (GNSSs are typical and popular positioning and attitude sensors used in MLS systems. In forest environments, because of the loss of signal due to occlusion and severe multipath effects, the positioning accuracy of GNSS is severely degraded, and even that of GNSS/INS decreases considerably. Light Detection and Ranging (LiDAR-based Simultaneous Localization and Mapping (SLAM can achieve higher positioning accuracy in environments containing many features and is commonly implemented in GNSS-denied indoor environments. Forests are different from an indoor environment in that the GNSS signal is available to some extent in a forest. Although the positioning accuracy of GNSS/INS is reduced, estimates of heading angle and velocity can maintain high accurate even with fewer satellites. GNSS/INS and the LiDAR-based SLAM technique can be effectively integrated to form a sustainable, highly accurate positioning and mapping solution for use in forests without additional hardware costs. In this study, information such as heading angles and velocities extracted from a GNSS/INS is utilized to improve the positioning accuracy of the SLAM solution, and two information-aided SLAM methods are proposed. First, a heading angle-aided SLAM (H-aided SLAM method is proposed that supplies the heading angle from GNSS/INS to SLAM. Field test results show that the horizontal positioning accuracy of an entire trajectory of 800 m is 0.13 m and is significantly improved (by 70% compared to that

  6. Rapid detection, classification and accurate alignment of up to a million or more related protein sequences.

    Science.gov (United States)

    Neuwald, Andrew F

    2009-08-01

    The patterns of sequence similarity and divergence present within functionally diverse, evolutionarily related proteins contain implicit information about corresponding biochemical similarities and differences. A first step toward accessing such information is to statistically analyze these patterns, which, in turn, requires that one first identify and accurately align a very large set of protein sequences. Ideally, the set should include many distantly related, functionally divergent subgroups. Because it is extremely difficult, if not impossible for fully automated methods to align such sequences correctly, researchers often resort to manual curation based on detailed structural and biochemical information. However, multiply-aligning vast numbers of sequences in this way is clearly impractical. This problem is addressed using Multiply-Aligned Profiles for Global Alignment of Protein Sequences (MAPGAPS). The MAPGAPS program uses a set of multiply-aligned profiles both as a query to detect and classify related sequences and as a template to multiply-align the sequences. It relies on Karlin-Altschul statistics for sensitivity and on PSI-BLAST (and other) heuristics for speed. Using as input a carefully curated multiple-profile alignment for P-loop GTPases, MAPGAPS correctly aligned weakly conserved sequence motifs within 33 distantly related GTPases of known structure. By comparison, the sequence- and structurally based alignment methods hmmalign and PROMALS3D misaligned at least 11 and 23 of these regions, respectively. When applied to a dataset of 65 million protein sequences, MAPGAPS identified, classified and aligned (with comparable accuracy) nearly half a million putative P-loop GTPase sequences. A C++ implementation of MAPGAPS is available at http://mapgaps.igs.umaryland.edu. Supplementary data are available at Bioinformatics online.

  7. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    Energy Technology Data Exchange (ETDEWEB)

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O' Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-08-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation.

  8. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    International Nuclear Information System (INIS)

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O'Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-01-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation

  9. MIDAS robust trend estimator for accurate GPS station velocities without step detection

    Science.gov (United States)

    Blewitt, Geoffrey; Kreemer, Corné; Hammond, William C.; Gazeaux, Julien

    2016-03-01

    Automatic estimation of velocities from GPS coordinate time series is becoming required to cope with the exponentially increasing flood of available data, but problems detectable to the human eye are often overlooked. This motivates us to find an automatic and accurate estimator of trend that is resistant to common problems such as step discontinuities, outliers, seasonality, skewness, and heteroscedasticity. Developed here, Median Interannual Difference Adjusted for Skewness (MIDAS) is a variant of the Theil-Sen median trend estimator, for which the ordinary version is the median of slopes vij = (xj-xi)/(tj-ti) computed between all data pairs i > j. For normally distributed data, Theil-Sen and least squares trend estimates are statistically identical, but unlike least squares, Theil-Sen is resistant to undetected data problems. To mitigate both seasonality and step discontinuities, MIDAS selects data pairs separated by 1 year. This condition is relaxed for time series with gaps so that all data are used. Slopes from data pairs spanning a step function produce one-sided outliers that can bias the median. To reduce bias, MIDAS removes outliers and recomputes the median. MIDAS also computes a robust and realistic estimate of trend uncertainty. Statistical tests using GPS data in the rigid North American plate interior show ±0.23 mm/yr root-mean-square (RMS) accuracy in horizontal velocity. In blind tests using synthetic data, MIDAS velocities have an RMS accuracy of ±0.33 mm/yr horizontal, ±1.1 mm/yr up, with a 5th percentile range smaller than all 20 automatic estimators tested. Considering its general nature, MIDAS has the potential for broader application in the geosciences.

  10. Fast and accurate denoising method applied to very high resolution optical remote sensing images

    Science.gov (United States)

    Masse, Antoine; Lefèvre, Sébastien; Binet, Renaud; Artigues, Stéphanie; Lassalle, Pierre; Blanchet, Gwendoline; Baillarin, Simon

    2017-10-01

    Restoration of Very High Resolution (VHR) optical Remote Sensing Image (RSI) is critical and leads to the problem of removing instrumental noise while keeping integrity of relevant information. Improving denoising in an image processing chain implies increasing image quality and improving performance of all following tasks operated by experts (photo-interpretation, cartography, etc.) or by algorithms (land cover mapping, change detection, 3D reconstruction, etc.). In a context of large industrial VHR image production, the selected denoising method should optimized accuracy and robustness with relevant information and saliency conservation, and rapidity due to the huge amount of data acquired and/or archived. Very recent research in image processing leads to a fast and accurate algorithm called Non Local Bayes (NLB) that we propose to adapt and optimize for VHR RSIs. This method is well suited for mass production thanks to its best trade-off between accuracy and computational complexity compared to other state-of-the-art methods. NLB is based on a simple principle: similar structures in an image have similar noise distribution and thus can be denoised with the same noise estimation. In this paper, we describe in details algorithm operations and performances, and analyze parameter sensibilities on various typical real areas observed in VHR RSIs.

  11. Accurate LC peak boundary detection for ¹⁶O/¹⁸O labeled LC-MS data.

    Science.gov (United States)

    Cui, Jian; Petritis, Konstantinos; Tegeler, Tony; Petritis, Brianne; Ma, Xuepo; Jin, Yufang; Gao, Shou-Jiang S J; Zhang, Jianqiu Michelle

    2013-01-01

    In liquid chromatography-mass spectrometry (LC-MS), parts of LC peaks are often corrupted by their co-eluting peptides, which results in increased quantification variance. In this paper, we propose to apply accurate LC peak boundary detection to remove the corrupted part of LC peaks. Accurate LC peak boundary detection is achieved by checking the consistency of intensity patterns within peptide elution time ranges. In addition, we remove peptides with erroneous mass assignment through model fitness check, which compares observed intensity patterns to theoretically constructed ones. The proposed algorithm can significantly improve the accuracy and precision of peptide ratio measurements.

  12. DB2: a probabilistic approach for accurate detection of tandem duplication breakpoints using paired-end reads.

    Science.gov (United States)

    Yavaş, Gökhan; Koyutürk, Mehmet; Gould, Meetha P; McMahon, Sarah; LaFramboise, Thomas

    2014-03-05

    With the advent of paired-end high throughput sequencing, it is now possible to identify various types of structural variation on a genome-wide scale. Although many methods have been proposed for structural variation detection, most do not provide precise boundaries for identified variants. In this paper, we propose a new method, Distribution Based detection of Duplication Boundaries (DB2), for accurate detection of tandem duplication breakpoints, an important class of structural variation, with high precision and recall. Our computational experiments on simulated data show that DB2 outperforms state-of-the-art methods in terms of finding breakpoints of tandem duplications, with a higher positive predictive value (precision) in calling the duplications' presence. In particular, DB2's prediction of tandem duplications is correct 99% of the time even for very noisy data, while narrowing down the space of possible breakpoints within a margin of 15 to 20 bps on the average. Most of the existing methods provide boundaries in ranges that extend to hundreds of bases with lower precision values. Our method is also highly robust to varying properties of the sequencing library and to the sizes of the tandem duplications, as shown by its stable precision, recall and mean boundary mismatch performance. We demonstrate our method's efficacy using both simulated paired-end reads, and those generated from a melanoma sample and two ovarian cancer samples. Newly discovered tandem duplications are validated using PCR and Sanger sequencing. Our method, DB2, uses discordantly aligned reads, taking into account the distribution of fragment length to predict tandem duplications along with their breakpoints on a donor genome. The proposed method fine tunes the breakpoint calls by applying a novel probabilistic framework that incorporates the empirical fragment length distribution to score each feasible breakpoint. DB2 is implemented in Java programming language and is freely available

  13. An accurate algorithm to match imperfectly matched images for lung tumor detection without markers.

    Science.gov (United States)

    Rozario, Timothy; Bereg, Sergey; Yan, Yulong; Chiu, Tsuicheng; Liu, Honghuan; Kearney, Vasant; Jiang, Lan; Mao, Weihua

    2015-05-08

    implanted and used as ground truth for tumor positions. Although other organs and bony structures introduced strong signals superimposed on tumors at some angles, this method accurately located tumors on every projection over 12 gantry angles. The maximum error was less than 2.2 mm, while the total average error was less than 0.9mm. This algorithm was capable of detecting tumors without markers, despite strong background signals.

  14. Direct Calculation of Permeability by High-Accurate Finite Difference and Numerical Integration Methods

    KAUST Repository

    Wang, Yi

    2016-07-21

    Velocity of fluid flow in underground porous media is 6~12 orders of magnitudes lower than that in pipelines. If numerical errors are not carefully controlled in this kind of simulations, high distortion of the final results may occur [1-4]. To fit the high accuracy demands of fluid flow simulations in porous media, traditional finite difference methods and numerical integration methods are discussed and corresponding high-accurate methods are developed. When applied to the direct calculation of full-tensor permeability for underground flow, the high-accurate finite difference method is confirmed to have numerical error as low as 10-5% while the high-accurate numerical integration method has numerical error around 0%. Thus, the approach combining the high-accurate finite difference and numerical integration methods is a reliable way to efficiently determine the characteristics of general full-tensor permeability such as maximum and minimum permeability components, principal direction and anisotropic ratio. Copyright © Global-Science Press 2016.

  15. CMASA: an accurate algorithm for detecting local protein structural similarity and its application to enzyme catalytic site annotation

    Directory of Open Access Journals (Sweden)

    Li Gong-Hua

    2010-08-01

    Full Text Available Abstract Background The rapid development of structural genomics has resulted in many "unknown function" proteins being deposited in Protein Data Bank (PDB, thus, the functional prediction of these proteins has become a challenge for structural bioinformatics. Several sequence-based and structure-based methods have been developed to predict protein function, but these methods need to be improved further, such as, enhancing the accuracy, sensitivity, and the computational speed. Here, an accurate algorithm, the CMASA (Contact MAtrix based local Structural Alignment algorithm, has been developed to predict unknown functions of proteins based on the local protein structural similarity. This algorithm has been evaluated by building a test set including 164 enzyme families, and also been compared to other methods. Results The evaluation of CMASA shows that the CMASA is highly accurate (0.96, sensitive (0.86, and fast enough to be used in the large-scale functional annotation. Comparing to both sequence-based and global structure-based methods, not only the CMASA can find remote homologous proteins, but also can find the active site convergence. Comparing to other local structure comparison-based methods, the CMASA can obtain the better performance than both FFF (a method using geometry to predict protein function and SPASM (a local structure alignment method; and the CMASA is more sensitive than PINTS and is more accurate than JESS (both are local structure alignment methods. The CMASA was applied to annotate the enzyme catalytic sites of the non-redundant PDB, and at least 166 putative catalytic sites have been suggested, these sites can not be observed by the Catalytic Site Atlas (CSA. Conclusions The CMASA is an accurate algorithm for detecting local protein structural similarity, and it holds several advantages in predicting enzyme active sites. The CMASA can be used in large-scale enzyme active site annotation. The CMASA can be available by the

  16. Stable and high order accurate difference methods for the elastic wave equation in discontinuous media

    KAUST Repository

    Duru, Kenneth

    2014-12-01

    © 2014 Elsevier Inc. In this paper, we develop a stable and systematic procedure for numerical treatment of elastic waves in discontinuous and layered media. We consider both planar and curved interfaces where media parameters are allowed to be discontinuous. The key feature is the highly accurate and provably stable treatment of interfaces where media discontinuities arise. We discretize in space using high order accurate finite difference schemes that satisfy the summation by parts rule. Conditions at layer interfaces are imposed weakly using penalties. By deriving lower bounds of the penalty strength and constructing discrete energy estimates we prove time stability. We present numerical experiments in two space dimensions to illustrate the usefulness of the proposed method for simulations involving typical interface phenomena in elastic materials. The numerical experiments verify high order accuracy and time stability.

  17. Towards Accurate Node-Based Detection of P2P Botnets

    Directory of Open Access Journals (Sweden)

    Chunyong Yin

    2014-01-01

    Full Text Available Botnets are a serious security threat to the current Internet infrastructure. In this paper, we propose a novel direction for P2P botnet detection called node-based detection. This approach focuses on the network characteristics of individual nodes. Based on our model, we examine node’s flows and extract the useful features over a given time period. We have tested our approach on real-life data sets and achieved detection rates of 99-100% and low false positives rates of 0–2%. Comparison with other similar approaches on the same data sets shows that our approach outperforms the existing approaches.

  18. An efficient discontinuous Galerkin finite element method for highly accurate solution of maxwell equations

    KAUST Repository

    Liu, Meilin

    2012-08-01

    A discontinuous Galerkin finite element method (DG-FEM) with a highly accurate time integration scheme for solving Maxwell equations is presented. The new time integration scheme is in the form of traditional predictor-corrector algorithms, PE CE m, but it uses coefficients that are obtained using a numerical scheme with fully controllable accuracy. Numerical results demonstrate that the proposed DG-FEM uses larger time steps than DG-FEM with classical PE CE) m schemes when high accuracy, which could be obtained using high-order spatial discretization, is required. © 1963-2012 IEEE.

  19. An efficient discontinuous Galerkin finite element method for highly accurate solution of maxwell equations

    KAUST Repository

    Liu, Meilin; Sirenko, Kostyantyn; Bagci, Hakan

    2012-01-01

    A discontinuous Galerkin finite element method (DG-FEM) with a highly accurate time integration scheme for solving Maxwell equations is presented. The new time integration scheme is in the form of traditional predictor-corrector algorithms, PE CE m, but it uses coefficients that are obtained using a numerical scheme with fully controllable accuracy. Numerical results demonstrate that the proposed DG-FEM uses larger time steps than DG-FEM with classical PE CE) m schemes when high accuracy, which could be obtained using high-order spatial discretization, is required. © 1963-2012 IEEE.

  20. Hydrogen sulfide detection based on reflection: from a poison test approach of ancient China to single-cell accurate localization.

    Science.gov (United States)

    Kong, Hao; Ma, Zhuoran; Wang, Song; Gong, Xiaoyun; Zhang, Sichun; Zhang, Xinrong

    2014-08-05

    With the inspiration of an ancient Chinese poison test approach, we report a rapid hydrogen sulfide detection strategy in specific areas of live cells using silver needles with good spatial resolution of 2 × 2 μm(2). Besides the accurate-localization ability, this reflection-based strategy also has attractive merits of convenience and robust response when free pretreatment and short detection time are concerned. The success of endogenous H2S level evaluation in cellular cytoplasm and nuclear of human A549 cells promises the application potential of our strategy in scientific research and medical diagnosis.

  1. Fast and Accurate Pedestrian Detection in a Truck’s Blind Spot Camera

    OpenAIRE

    Van Beeck, Kristof; Goedemé, Toon

    2015-01-01

    We propose a multi-pedestrian detection and tracking framework targeting a specific application: detecting vulnerable road users in a truck’s blind spot zone. Existing safety solutions are not able to handle this problem completely. Therefore we aim to develop an active safety system which warns the truck driver if pedestrians are present in the truck’s blind spot zone, using solely the vision input from the truck’s blind spot camera. This is not a trivial task, since—aside from the large dis...

  2. A method for accurate detection of genomic microdeletions using real-time quantitative PCR

    Directory of Open Access Journals (Sweden)

    Bassett Anne S

    2005-12-01

    Full Text Available Abstract Background Quantitative Polymerase Chain Reaction (qPCR is a well-established method for quantifying levels of gene expression, but has not been routinely applied to the detection of constitutional copy number alterations of human genomic DNA. Microdeletions or microduplications of the human genome are associated with a variety of genetic disorders. Although, clinical laboratories routinely use fluorescence in situ hybridization (FISH to identify such cryptic genomic alterations, there remains a significant number of individuals in which constitutional genomic imbalance is suspected, based on clinical parameters, but cannot be readily detected using current cytogenetic techniques. Results In this study, a novel application for real-time qPCR is presented that can be used to reproducibly detect chromosomal microdeletions and microduplications. This approach was applied to DNA from a series of patient samples and controls to validate genomic copy number alteration at cytoband 22q11. The study group comprised 12 patients with clinical symptoms of chromosome 22q11 deletion syndrome (22q11DS, 1 patient trisomic for 22q11 and 4 normal controls. 6 of the patients (group 1 had known hemizygous deletions, as detected by standard diagnostic FISH, whilst the remaining 6 patients (group 2 were classified as 22q11DS negative using the clinical FISH assay. Screening of the patients and controls with a set of 10 real time qPCR primers, spanning the 22q11.2-deleted region and flanking sequence, confirmed the FISH assay results for all patients with 100% concordance. Moreover, this qPCR enabled a refinement of the region of deletion at 22q11. Analysis of DNA from chromosome 22 trisomic sample demonstrated genomic duplication within 22q11. Conclusion In this paper we present a qPCR approach for the detection of chromosomal microdeletions and microduplications. The strategic use of in silico modelling for qPCR primer design to avoid regions of repetitive

  3. Avulsion research using flume experiments and highly accurate and temporal-rich SfM datasets

    Science.gov (United States)

    Javernick, L.; Bertoldi, W.; Vitti, A.

    2017-12-01

    SfM's ability to produce high-quality, large-scale digital elevation models (DEMs) of complicated and rapidly evolving systems has made it a valuable technique for low-budget researchers and practitioners. While SfM has provided valuable datasets that capture single-flood event DEMs, there is an increasing scientific need to capture higher temporal resolution datasets that can quantify the evolutionary processes instead of pre- and post-flood snapshots. However, flood events' dangerous field conditions and image matching challenges (e.g. wind, rain) prevent quality SfM-image acquisition. Conversely, flume experiments offer opportunities to document flood events, but achieving consistent and accurate DEMs to detect subtle changes in dry and inundated areas remains a challenge for SfM (e.g. parabolic error signatures).This research aimed at investigating the impact of naturally occurring and manipulated avulsions on braided river morphology and on the encroachment of floodplain vegetation, using laboratory experiments. This required DEMs with millimeter accuracy and precision and at a temporal resolution to capture the processes. SfM was chosen as it offered the most practical method. Through redundant local network design and a meticulous ground control point (GCP) survey with a Leica Total Station in red laser configuration (reported 2 mm accuracy), the SfM residual errors compared to separate ground truthing data produced mean errors of 1.5 mm (accuracy) and standard deviations of 1.4 mm (precision) without parabolic error signatures. Lighting conditions in the flume were limited to uniform, oblique, and filtered LED strips, which removed glint and thus improved bed elevation mean errors to 4 mm, but errors were further reduced by means of an open source software for refraction correction. The obtained datasets have provided the ability to quantify how small flood events with avulsion can have similar morphologic and vegetation impacts as large flood events

  4. An investigation of highly accurate and precise robotic hole measurements using non-contact devices

    Directory of Open Access Journals (Sweden)

    Usman Zahid

    2016-01-01

    Full Text Available Industrial robots arms are widely used in manufacturing industry because of their support for automation. However, in metrology, robots have had limited application due to their insufficient accuracy. Even using error compensation and calibration methods, robots are not effective for micrometre (μm level metrology. Non-contact measurement devices can potentially enable the use of robots for highly accurate metrology. However, the use of such devices on robots has not been investigated. The research work reported in this paper explores the use of different non-contact measurement devices on an industrial robot. The aim is to experimentally investigate the effects of robot movements on the accuracy and precision of measurements. The focus has been on assessing the ability to accurately measure various geometric and surface parameters of holes despite the inherent inaccuracies of industrial robot. This involves the measurement of diameter, roundness and surface roughness. The study also includes scanning of holes for measuring internal features such as start and end point of a taper. Two different non-contact measurement devices based on different technologies are investigated. Furthermore, effects of eccentricity, vibrations and thermal variations are also assessed. The research contributes towards the use of robots for highly accurate and precise robotic metrology.

  5. A flexible and accurate digital volume correlation method applicable to high-resolution volumetric images

    Science.gov (United States)

    Pan, Bing; Wang, Bo

    2017-10-01

    Digital volume correlation (DVC) is a powerful technique for quantifying interior deformation within solid opaque materials and biological tissues. In the last two decades, great efforts have been made to improve the accuracy and efficiency of the DVC algorithm. However, there is still a lack of a flexible, robust and accurate version that can be efficiently implemented in personal computers with limited RAM. This paper proposes an advanced DVC method that can realize accurate full-field internal deformation measurement applicable to high-resolution volume images with up to billions of voxels. Specifically, a novel layer-wise reliability-guided displacement tracking strategy combined with dynamic data management is presented to guide the DVC computation from slice to slice. The displacements at specified calculation points in each layer are computed using the advanced 3D inverse-compositional Gauss-Newton algorithm with the complete initial guess of the deformation vector accurately predicted from the computed calculation points. Since only limited slices of interest in the reference and deformed volume images rather than the whole volume images are required, the DVC calculation can thus be efficiently implemented on personal computers. The flexibility, accuracy and efficiency of the presented DVC approach are demonstrated by analyzing computer-simulated and experimentally obtained high-resolution volume images.

  6. Accurate Detection of Methicillin-Resistant Staphylococcus aureus in Mixtures by Use of Single-Bacterium Duplex Droplet Digital PCR.

    Science.gov (United States)

    Luo, Jun; Li, Junhua; Yang, Hang; Yu, Junping; Wei, Hongping

    2017-10-01

    Accurate and rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is needed to screen MRSA carriers and improve treatment. The current widely used duplex PCR methods are not able to differentiate MRSA from coexisting methicillin-susceptible S. aureus (MSSA) or other methicillin-resistant staphylococci. In this study, we aimed to develop a direct method for accurate and rapid detection of MRSA in clinical samples from open environments, such as nasal swabs. The new molecular assay is based on detecting the cooccurrence of nuc and mecA markers in a single bacterial cell by utilizing droplet digital PCR (ddPCR) with the chimeric lysin ClyH for cell lysis. The method consists of (i) dispersion of an intact single bacterium into nanoliter droplets, (ii) temperature-controlled release of genomic DNA (gDNA) by ClyH at 37°C, and (iii) amplification and detection of the markers ( nuc and mecA ) using standard TaqMan chemistries with ddPCR. Results were analyzed based on MRSA index ratios used for indicating the presence of the duplex-positive markers in droplets. The method was able to achieve an absolute limit of detection (LOD) of 2,900 CFU/ml for MRSA in nasal swabs spiked with excess amounts of Escherichia coli , MSSA, and other mecA -positive bacteria within 4 h. Initial testing of 104 nasal swabs showed that the method had 100% agreement with the standard culture method, while the normal duplex qPCR method had only about 87.5% agreement. The single-bacterium duplex ddPCR assay is rapid and powerful for more accurate detection of MRSA directly from clinical specimens. Copyright © 2017 American Society for Microbiology.

  7. An accurate, fast, and scalable solver for high-frequency wave propagation

    Science.gov (United States)

    Zepeda-Núñez, L.; Taus, M.; Hewett, R.; Demanet, L.

    2017-12-01

    In many science and engineering applications, solving time-harmonic high-frequency wave propagation problems quickly and accurately is of paramount importance. For example, in geophysics, particularly in oil exploration, such problems can be the forward problem in an iterative process for solving the inverse problem of subsurface inversion. It is important to solve these wave propagation problems accurately in order to efficiently obtain meaningful solutions of the inverse problems: low order forward modeling can hinder convergence. Additionally, due to the volume of data and the iterative nature of most optimization algorithms, the forward problem must be solved many times. Therefore, a fast solver is necessary to make solving the inverse problem feasible. For time-harmonic high-frequency wave propagation, obtaining both speed and accuracy is historically challenging. Recently, there have been many advances in the development of fast solvers for such problems, including methods which have linear complexity with respect to the number of degrees of freedom. While most methods scale optimally only in the context of low-order discretizations and smooth wave speed distributions, the method of polarized traces has been shown to retain optimal scaling for high-order discretizations, such as hybridizable discontinuous Galerkin methods and for highly heterogeneous (and even discontinuous) wave speeds. The resulting fast and accurate solver is consequently highly attractive for geophysical applications. To date, this method relies on a layered domain decomposition together with a preconditioner applied in a sweeping fashion, which has limited straight-forward parallelization. In this work, we introduce a new version of the method of polarized traces which reveals more parallel structure than previous versions while preserving all of its other advantages. We achieve this by further decomposing each layer and applying the preconditioner to these new components separately and

  8. Novel fMRI working memory paradigm accurately detects cognitive impairment in Multiple Sclerosis

    Science.gov (United States)

    Nelson, Flavia; Akhtar, Mohammad A.; Zúñiga, Edward; Perez, Carlos A.; Hasan, Khader M.; Wilken, Jeffrey; Wolinsky, Jerry S.; Narayana, Ponnada A.; Steinberg, Joel L.

    2016-01-01

    Background Cognitive impairment (CI) cannot be diagnosed by MRI. Functional MRI (fMRI) paradigms such as the immediate/delayed memory task (I/DMT), detect varying degrees of working memory. Preliminary findings using I/DMT, showed differences in Blood Oxygenation Level Dependent (BOLD) activation between impaired (MSCI, n=12) and non-impaired (MSNI, n=9) MS patients. Objectives To confirm CI detection based on I/DMT’ BOLD activation in a larger cohort of MS patients. The role of T2 lesion volume (LV) and EDSS in magnitude of BOLD signal were also sought. Methods Fifty patients [EDSS mean (m) = 3.2, DD m =12 yr., age m =40yr.] underwent the Minimal Assessment of Cognitive Function in MS (MACFIMS) and the I/DMT. Working-memory activation (WMa) represents BOLD signal during DMT minus signal during IMT. CI was based on MACFIMS. Results 10 MSNI, 30 MSCI and 4 borderline patients were included in analyses. ANOVA showed MSNI had significantly greater WMa than MSCI, in the left (L) prefrontal cortex and L supplementary motor area (p = 0.032). Regression analysis showed significant inverse correlations between WMa and T2 LV/EDSS in similar areas (p = 0.005, 0.004 respectively). Conclusion I/DMT-based BOLD activation detects CI in MS, larger studies are needed to confirm these findings. PMID:27613119

  9. GUIDANCE2: accurate detection of unreliable alignment regions accounting for the uncertainty of multiple parameters.

    Science.gov (United States)

    Sela, Itamar; Ashkenazy, Haim; Katoh, Kazutaka; Pupko, Tal

    2015-07-01

    Inference of multiple sequence alignments (MSAs) is a critical part of phylogenetic and comparative genomics studies. However, from the same set of sequences different MSAs are often inferred, depending on the methodologies used and the assumed parameters. Much effort has recently been devoted to improving the ability to identify unreliable alignment regions. Detecting such unreliable regions was previously shown to be important for downstream analyses relying on MSAs, such as the detection of positive selection. Here we developed GUIDANCE2, a new integrative methodology that accounts for: (i) uncertainty in the process of indel formation, (ii) uncertainty in the assumed guide tree and (iii) co-optimal solutions in the pairwise alignments, used as building blocks in progressive alignment algorithms. We compared GUIDANCE2 with seven methodologies to detect unreliable MSA regions using extensive simulations and empirical benchmarks. We show that GUIDANCE2 outperforms all previously developed methodologies. Furthermore, GUIDANCE2 also provides a set of alternative MSAs which can be useful for downstream analyses. The novel algorithm is implemented as a web-server, available at: http://guidance.tau.ac.il. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  10. Microarray MAPH: accurate array-based detection of relative copy number in genomic DNA.

    Science.gov (United States)

    Gibbons, Brian; Datta, Parikkhit; Wu, Ying; Chan, Alan; Al Armour, John

    2006-06-30

    Current methods for measurement of copy number do not combine all the desirable qualities of convenience, throughput, economy, accuracy and resolution. In this study, to improve the throughput associated with Multiplex Amplifiable Probe Hybridisation (MAPH) we aimed to develop a modification based on the 3-Dimensional, Flow-Through Microarray Platform from PamGene International. In this new method, electrophoretic analysis of amplified products is replaced with photometric analysis of a probed oligonucleotide array. Copy number analysis of hybridised probes is based on a dual-label approach by comparing the intensity of Cy3-labelled MAPH probes amplified from test samples co-hybridised with similarly amplified Cy5-labelled reference MAPH probes. The key feature of using a hybridisation-based end point with MAPH is that discrimination of amplified probes is based on sequence and not fragment length. In this study we showed that microarray MAPH measurement of PMP22 gene dosage correlates well with PMP22 gene dosage determined by capillary MAPH and that copy number was accurately reported in analyses of DNA from 38 individuals, 12 of which were known to have Charcot-Marie-Tooth disease type 1A (CMT1A). Measurement of microarray-based endpoints for MAPH appears to be of comparable accuracy to electrophoretic methods, and holds the prospect of fully exploiting the potential multiplicity of MAPH. The technology has the potential to simplify copy number assays for genes with a large number of exons, or of expanded sets of probes from dispersed genomic locations.

  11. Novel fMRI working memory paradigm accurately detects cognitive impairment in multiple sclerosis.

    Science.gov (United States)

    Nelson, Flavia; Akhtar, Mohammad A; Zúñiga, Edward; Perez, Carlos A; Hasan, Khader M; Wilken, Jeffrey; Wolinsky, Jerry S; Narayana, Ponnada A; Steinberg, Joel L

    2017-05-01

    Cognitive impairment (CI) cannot be diagnosed by magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) paradigms, such as the immediate/delayed memory task (I/DMT), detect varying degrees of working memory (WM). Preliminary findings using I/DMT showed differences in blood oxygenation level dependent (BOLD) activation between impaired (MSCI, n = 12) and non-impaired (MSNI, n = 9) multiple sclerosis (MS) patients. The aim of the study was to confirm CI detection based on I/DMT BOLD activation in a larger cohort of MS patients. The role of T2 lesion volume (LV) and Expanded Disability Status Scale (EDSS) in magnitude of BOLD signal was also sought. A total of 50 patients (EDSS mean ( m) = 3.2, disease duration (DD) m = 12 years, and age m = 40 years) underwent the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) and I/DMT. Working memory activation (WMa) represents BOLD signal during DMT minus signal during IMT. CI was based on MACFIMS. A total of 10 MSNI, 30 MSCI, and 4 borderline patients were included in the analyses. Analysis of variance (ANOVA) showed MSNI had significantly greater WMa than MSCI, in the left prefrontal cortex and left supplementary motor area ( p = 0.032). Regression analysis showed significant inverse correlations between WMa and T2 LV/EDSS in similar areas ( p = 0.005, 0.004, respectively). I/DMT-based BOLD activation detects CI in MS. Larger studies are needed to confirm these findings.

  12. Highly accurate fluorogenic DNA sequencing with information theory-based error correction.

    Science.gov (United States)

    Chen, Zitian; Zhou, Wenxiong; Qiao, Shuo; Kang, Li; Duan, Haifeng; Xie, X Sunney; Huang, Yanyi

    2017-12-01

    Eliminating errors in next-generation DNA sequencing has proved challenging. Here we present error-correction code (ECC) sequencing, a method to greatly improve sequencing accuracy by combining fluorogenic sequencing-by-synthesis (SBS) with an information theory-based error-correction algorithm. ECC embeds redundancy in sequencing reads by creating three orthogonal degenerate sequences, generated by alternate dual-base reactions. This is similar to encoding and decoding strategies that have proved effective in detecting and correcting errors in information communication and storage. We show that, when combined with a fluorogenic SBS chemistry with raw accuracy of 98.1%, ECC sequencing provides single-end, error-free sequences up to 200 bp. ECC approaches should enable accurate identification of extremely rare genomic variations in various applications in biology and medicine.

  13. Color-SIFT model: a robust and an accurate shot boundary detection algorithm

    Science.gov (United States)

    Sharmila Kumari, M.; Shekar, B. H.

    2010-02-01

    In this paper, a new technique called color-SIFT model is devised for shot boundary detection. Unlike scale invariant feature transform model that uses only grayscale information and misses important visual information regarding color, here we have adopted different color planes to extract keypoints which are subsequently used to detect shot boundaries. The basic SIFT model has four stages namely scale-space peak selection, keypoint localization, orientation assignment and keypoint descriptor and all these four stages were employed to extract key descriptors in each color plane. The proposed model works on three different color planes and a fusion has been made to take a decision on number of keypoint matches for shot boundary identification and hence is different from the color global scale invariant feature transform that works on quantized images. In addition, the proposed algorithm possess invariance to linear transformation and robust to occlusion and noisy environment. Experiments have been conducted on the standard TRECVID video database to reveal the performance of the proposed model.

  14. Microarray MAPH: accurate array-based detection of relative copy number in genomic DNA

    Directory of Open Access Journals (Sweden)

    Chan Alan

    2006-06-01

    Full Text Available Abstract Background Current methods for measurement of copy number do not combine all the desirable qualities of convenience, throughput, economy, accuracy and resolution. In this study, to improve the throughput associated with Multiplex Amplifiable Probe Hybridisation (MAPH we aimed to develop a modification based on the 3-Dimensional, Flow-Through Microarray Platform from PamGene International. In this new method, electrophoretic analysis of amplified products is replaced with photometric analysis of a probed oligonucleotide array. Copy number analysis of hybridised probes is based on a dual-label approach by comparing the intensity of Cy3-labelled MAPH probes amplified from test samples co-hybridised with similarly amplified Cy5-labelled reference MAPH probes. The key feature of using a hybridisation-based end point with MAPH is that discrimination of amplified probes is based on sequence and not fragment length. Results In this study we showed that microarray MAPH measurement of PMP22 gene dosage correlates well with PMP22 gene dosage determined by capillary MAPH and that copy number was accurately reported in analyses of DNA from 38 individuals, 12 of which were known to have Charcot-Marie-Tooth disease type 1A (CMT1A. Conclusion Measurement of microarray-based endpoints for MAPH appears to be of comparable accuracy to electrophoretic methods, and holds the prospect of fully exploiting the potential multiplicity of MAPH. The technology has the potential to simplify copy number assays for genes with a large number of exons, or of expanded sets of probes from dispersed genomic locations.

  15. Delta flow: An accurate, reliable system for detecting kicks and loss of circulation during drilling

    Energy Technology Data Exchange (ETDEWEB)

    Speers, J.M.; Gehrig, G.F.

    1987-12-01

    A system to monitor drilling-fluid flow rate has been developed that detects kicks and lost returns in floating, fixed-platform, and land-base drilling operations. The system uses flowmeters that monitor the flow rates of drilling fluids entering the borehole through the standpipe and leaving the well through the return flowline. These readings are processed in a computer-based, data-acquisition system to form a filtered delta-flow signal that identified the occurrence of downhole fluid gains or losses. The system is designed to trip an alarm when a gain or loss exceeds 25 gal/min (1.6 dm/sup 3//s), even in a floating drilling environment. This sensitivity will generally keep gains or losses to less than 5 bbl (0.8 m/sup 3/).

  16. Defining Allowable Physical Property Variations for High Accurate Measurements on Polymer Parts

    DEFF Research Database (Denmark)

    Mohammadi, Ali; Sonne, Mads Rostgaard; Madruga, Daniel González

    2015-01-01

    Measurement conditions and material properties have a significant impact on the dimensions of a part, especially for polymers parts. Temperature variation causes part deformations that increase the uncertainty of the measurement process. Current industrial tolerances of a few micrometres demand...... high accurate measurements in non-controlled ambient. Most of polymer parts are manufactured by injection moulding and their inspection is carried out after stabilization, around 200 hours. The overall goal of this work is to reach ±5μm in uncertainty measurements a polymer products which...

  17. Highly accurate analytical energy of a two-dimensional exciton in a constant magnetic field

    International Nuclear Information System (INIS)

    Hoang, Ngoc-Tram D.; Nguyen, Duy-Anh P.; Hoang, Van-Hung; Le, Van-Hoang

    2016-01-01

    Explicit expressions are given for analytically describing the dependence of the energy of a two-dimensional exciton on magnetic field intensity. These expressions are highly accurate with the precision of up to three decimal places for the whole range of the magnetic field intensity. The results are shown for the ground state and some excited states; moreover, we have all formulae to obtain similar expressions of any excited state. Analysis of numerical results shows that the precision of three decimal places is maintained for the excited states with the principal quantum number of up to n=100.

  18. Highly accurate analytical energy of a two-dimensional exciton in a constant magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, Ngoc-Tram D. [Department of Physics, Ho Chi Minh City University of Pedagogy 280, An Duong Vuong Street, District 5, Ho Chi Minh City (Viet Nam); Nguyen, Duy-Anh P. [Department of Natural Science, Thu Dau Mot University, 6, Tran Van On Street, Thu Dau Mot City, Binh Duong Province (Viet Nam); Hoang, Van-Hung [Department of Physics, Ho Chi Minh City University of Pedagogy 280, An Duong Vuong Street, District 5, Ho Chi Minh City (Viet Nam); Le, Van-Hoang, E-mail: levanhoang@tdt.edu.vn [Atomic Molecular and Optical Physics Research Group, Ton Duc Thang University, 19 Nguyen Huu Tho Street, Tan Phong Ward, District 7, Ho Chi Minh City (Viet Nam); Faculty of Applied Sciences, Ton Duc Thang University, 19 Nguyen Huu Tho Street, Tan Phong Ward, District 7, Ho Chi Minh City (Viet Nam)

    2016-08-15

    Explicit expressions are given for analytically describing the dependence of the energy of a two-dimensional exciton on magnetic field intensity. These expressions are highly accurate with the precision of up to three decimal places for the whole range of the magnetic field intensity. The results are shown for the ground state and some excited states; moreover, we have all formulae to obtain similar expressions of any excited state. Analysis of numerical results shows that the precision of three decimal places is maintained for the excited states with the principal quantum number of up to n=100.

  19. Small arteries can be accurately studied in vivo, using high frequency ultrasound

    DEFF Research Database (Denmark)

    Nielsen, T H; Iversen, Helle Klingenberg; Tfelt-Hansen, P

    1993-01-01

    We have validated measurements of diameters of the superficial temporal artery and other small arteries in man with a newly developed 20 MHz ultrasound scanner with A, B and M-mode imaging. The diameter of a reference object was 1.202 mm vs. 1.205 mm as measured by stereomicroscopy (nonsignifican......-gauge plethysmography (nonsignificant). Pulsations were 4.6% in the radial artery. We conclude that high frequency ultrasound provides an accurate and reproducible measure of the diameter of small and medium sized human arteries in vivo....

  20. Towards the accurate electronic structure descriptions of typical high-constant dielectrics

    Science.gov (United States)

    Jiang, Ting-Ting; Sun, Qing-Qing; Li, Ye; Guo, Jiao-Jiao; Zhou, Peng; Ding, Shi-Jin; Zhang, David Wei

    2011-05-01

    High-constant dielectrics have gained considerable attention due to their wide applications in advanced devices, such as gate oxides in metal-oxide-semiconductor devices and insulators in high-density metal-insulator-metal capacitors. However, the theoretical investigations of these materials cannot fulfil the requirement of experimental development, especially the requirement for the accurate description of band structures. We performed first-principles calculations based on the hybrid density functionals theory to investigate several typical high-k dielectrics such as Al2O3, HfO2, ZrSiO4, HfSiO4, La2O3 and ZrO2. The band structures of these materials are well described within the framework of hybrid density functionals theory. The band gaps of Al2O3, HfO2, ZrSiO4, HfSiO4, La2O3 and ZrO2are calculated to be 8.0 eV, 5.6 eV, 6.2 eV, 7.1 eV, 5.3 eV and 5.0 eV, respectively, which are very close to the experimental values and far more accurate than those obtained by the traditional generalized gradient approximation method.

  1. Highly accurate and fast optical penetration-based silkworm gender separation system

    Science.gov (United States)

    Kamtongdee, Chakkrit; Sumriddetchkajorn, Sarun; Chanhorm, Sataporn

    2015-07-01

    Based on our research work in the last five years, this paper highlights our innovative optical sensing system that can identify and separate silkworm gender highly suitable for sericulture industry. The key idea relies on our proposed optical penetration concepts and once combined with simple image processing operations leads to high accuracy in identifying of silkworm gender. Inside the system, there are electronic and mechanical parts that assist in controlling the overall system operation, processing the optical signal, and separating the female from male silkworm pupae. With current system performance, we achieve a very highly accurate more than 95% in identifying gender of silkworm pupae with an average system operational speed of 30 silkworm pupae/minute. Three of our systems are already in operation at Thailand's Queen Sirikit Sericulture Centers.

  2. Accurate determination of the diffusion coefficient of proteins by Fourier analysis with whole column imaging detection.

    Science.gov (United States)

    Zarabadi, Atefeh S; Pawliszyn, Janusz

    2015-02-17

    Analysis in the frequency domain is considered a powerful tool to elicit precise information from spectroscopic signals. In this study, the Fourier transformation technique is employed to determine the diffusion coefficient (D) of a number of proteins in the frequency domain. Analytical approaches are investigated for determination of D from both experimental and data treatment viewpoints. The diffusion process is modeled to calculate diffusion coefficients based on the Fourier transformation solution to Fick's law equation, and its results are compared to time domain results. The simulations characterize optimum spatial and temporal conditions and demonstrate the noise tolerance of the method. The proposed model is validated by its application for the electropherograms from the diffusion path of a set of proteins. Real-time dynamic scanning is conducted to monitor dispersion by employing whole column imaging detection technology in combination with capillary isoelectric focusing (CIEF) and the imaging plug flow (iPF) experiment. These experimental techniques provide different peak shapes, which are utilized to demonstrate the Fourier transformation ability in extracting diffusion coefficients out of irregular shape signals. Experimental results confirmed that the Fourier transformation procedure substantially enhanced the accuracy of the determined values compared to those obtained in the time domain.

  3. Machine learning algorithm accurately detects fMRI signature of vulnerability to major depression.

    Science.gov (United States)

    Sato, João R; Moll, Jorge; Green, Sophie; Deakin, John F W; Thomaz, Carlos E; Zahn, Roland

    2015-08-30

    Standard functional magnetic resonance imaging (fMRI) analyses cannot assess the potential of a neuroimaging signature as a biomarker to predict individual vulnerability to major depression (MD). Here, we use machine learning for the first time to address this question. Using a recently identified neural signature of guilt-selective functional disconnection, the classification algorithm was able to distinguish remitted MD from control participants with 78.3% accuracy. This demonstrates the high potential of our fMRI signature as a biomarker of MD vulnerability. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  4. A highly accurate finite-difference method with minimum dispersion error for solving the Helmholtz equation

    KAUST Repository

    Wu, Zedong

    2018-04-05

    Numerical simulation of the acoustic wave equation in either isotropic or anisotropic media is crucial to seismic modeling, imaging and inversion. Actually, it represents the core computation cost of these highly advanced seismic processing methods. However, the conventional finite-difference method suffers from severe numerical dispersion errors and S-wave artifacts when solving the acoustic wave equation for anisotropic media. We propose a method to obtain the finite-difference coefficients by comparing its numerical dispersion with the exact form. We find the optimal finite difference coefficients that share the dispersion characteristics of the exact equation with minimal dispersion error. The method is extended to solve the acoustic wave equation in transversely isotropic (TI) media without S-wave artifacts. Numerical examples show that the method is is highly accurate and efficient.

  5. Rapid and Accurate Machine Learning Recognition of High Performing Metal Organic Frameworks for CO2 Capture.

    Science.gov (United States)

    Fernandez, Michael; Boyd, Peter G; Daff, Thomas D; Aghaji, Mohammad Zein; Woo, Tom K

    2014-09-04

    In this work, we have developed quantitative structure-property relationship (QSPR) models using advanced machine learning algorithms that can rapidly and accurately recognize high-performing metal organic framework (MOF) materials for CO2 capture. More specifically, QSPR classifiers have been developed that can, in a fraction of a section, identify candidate MOFs with enhanced CO2 adsorption capacity (>1 mmol/g at 0.15 bar and >4 mmol/g at 1 bar). The models were tested on a large set of 292 050 MOFs that were not part of the training set. The QSPR classifier could recover 945 of the top 1000 MOFs in the test set while flagging only 10% of the whole library for compute intensive screening. Thus, using the machine learning classifiers as part of a high-throughput screening protocol would result in an order of magnitude reduction in compute time and allow intractably large structure libraries and search spaces to be screened.

  6. Energy stable and high-order-accurate finite difference methods on staggered grids

    Science.gov (United States)

    O'Reilly, Ossian; Lundquist, Tomas; Dunham, Eric M.; Nordström, Jan

    2017-10-01

    For wave propagation over distances of many wavelengths, high-order finite difference methods on staggered grids are widely used due to their excellent dispersion properties. However, the enforcement of boundary conditions in a stable manner and treatment of interface problems with discontinuous coefficients usually pose many challenges. In this work, we construct a provably stable and high-order-accurate finite difference method on staggered grids that can be applied to a broad class of boundary and interface problems. The staggered grid difference operators are in summation-by-parts form and when combined with a weak enforcement of the boundary conditions, lead to an energy stable method on multiblock grids. The general applicability of the method is demonstrated by simulating an explosive acoustic source, generating waves reflecting against a free surface and material discontinuity.

  7. Efficient and accurate nearest neighbor and closest pair search in high-dimensional space

    KAUST Repository

    Tao, Yufei

    2010-07-01

    Nearest Neighbor (NN) search in high-dimensional space is an important problem in many applications. From the database perspective, a good solution needs to have two properties: (i) it can be easily incorporated in a relational database, and (ii) its query cost should increase sublinearly with the dataset size, regardless of the data and query distributions. Locality-Sensitive Hashing (LSH) is a well-known methodology fulfilling both requirements, but its current implementations either incur expensive space and query cost, or abandon its theoretical guarantee on the quality of query results. Motivated by this, we improve LSH by proposing an access method called the Locality-Sensitive B-tree (LSB-tree) to enable fast, accurate, high-dimensional NN search in relational databases. The combination of several LSB-trees forms a LSB-forest that has strong quality guarantees, but improves dramatically the efficiency of the previous LSH implementation having the same guarantees. In practice, the LSB-tree itself is also an effective index which consumes linear space, supports efficient updates, and provides accurate query results. In our experiments, the LSB-tree was faster than: (i) iDistance (a famous technique for exact NN search) by two orders ofmagnitude, and (ii) MedRank (a recent approximate method with nontrivial quality guarantees) by one order of magnitude, and meanwhile returned much better results. As a second step, we extend our LSB technique to solve another classic problem, called Closest Pair (CP) search, in high-dimensional space. The long-term challenge for this problem has been to achieve subquadratic running time at very high dimensionalities, which fails most of the existing solutions. We show that, using a LSB-forest, CP search can be accomplished in (worst-case) time significantly lower than the quadratic complexity, yet still ensuring very good quality. In practice, accurate answers can be found using just two LSB-trees, thus giving a substantial

  8. Utilization of independent component analysis for accurate pathological ripple detection in intracranial EEG recordings recorded extra- and intra-operatively.

    Science.gov (United States)

    Shimamoto, Shoichi; Waldman, Zachary J; Orosz, Iren; Song, Inkyung; Bragin, Anatol; Fried, Itzhak; Engel, Jerome; Staba, Richard; Sharan, Ashwini; Wu, Chengyuan; Sperling, Michael R; Weiss, Shennan A

    2018-01-01

    To develop and validate a detector that identifies ripple (80-200 Hz) events in intracranial EEG (iEEG) recordings in a referential montage and utilizes independent component analysis (ICA) to eliminate or reduce high-frequency artifact contamination. Also, investigate the correspondence of detected ripples and the seizure onset zone (SOZ). iEEG recordings from 16 patients were first band-pass filtered (80-600 Hz) and Infomax ICA was next applied to derive the first independent component (IC1). IC1 was subsequently pruned, and an artifact index was derived to reduce the identification of high-frequency events introduced by the reference electrode signal. A Hilbert detector identified ripple events in the processed iEEG recordings using amplitude and duration criteria. The identified ripple events were further classified and characterized as true or false ripple on spikes, or ripples on oscillations by utilizing a topographical analysis to their time-frequency plot, and confirmed by visual inspection. The signal to noise ratio was improved by pruning IC1. The precision of the detector for ripple events was 91.27 ± 4.3%, and the sensitivity of the detector was 79.4 ± 3.0% (N = 16 patients, 5842 ripple events). The sensitivity and precision of the detector was equivalent in iEEG recordings obtained during sleep or intra-operatively. Across all the patients, true ripple on spike rates and also the rates of false ripple on spikes, that were generated due to filter ringing, classified the seizure onset zone (SOZ) with an area under the receiver operating curve (AUROC) of >76%. The magnitude and spectral content of true ripple on spikes generated in the SOZ was distinct as compared with the ripples generated in the NSOZ (p ripple rates and properties defined using this approach may accurately delineate the seizure onset zone. Strategies to improve the spatial resolution of intracranial EEG and reduce artifact can help improve the clinical utility of

  9. Fast and accurate detection of spread source in large complex networks.

    Science.gov (United States)

    Paluch, Robert; Lu, Xiaoyan; Suchecki, Krzysztof; Szymański, Bolesław K; Hołyst, Janusz A

    2018-02-06

    Spread over complex networks is a ubiquitous process with increasingly wide applications. Locating spread sources is often important, e.g. finding the patient one in epidemics, or source of rumor spreading in social network. Pinto, Thiran and Vetterli introduced an algorithm (PTVA) to solve the important case of this problem in which a limited set of nodes act as observers and report times at which the spread reached them. PTVA uses all observers to find a solution. Here we propose a new approach in which observers with low quality information (i.e. with large spread encounter times) are ignored and potential sources are selected based on the likelihood gradient from high quality observers. The original complexity of PTVA is O(N α ), where α ∈ (3,4) depends on the network topology and number of observers (N denotes the number of nodes in the network). Our Gradient Maximum Likelihood Algorithm (GMLA) reduces this complexity to O (N 2 log (N)). Extensive numerical tests performed on synthetic networks and real Gnutella network with limitation that id's of spreaders are unknown to observers demonstrate that for scale-free networks with such limitation GMLA yields higher quality localization results than PTVA does.

  10. Use of Monocrystalline Silicon as Tool Material for Highly Accurate Blanking of Thin Metal Foils

    International Nuclear Information System (INIS)

    Hildering, Sven; Engel, Ulf; Merklein, Marion

    2011-01-01

    The trend towards miniaturisation of metallic mass production components combined with increased component functionality is still unbroken. Manufacturing these components by forming and blanking offers economical and ecological advantages combined with the needed accuracy. The complexity of producing tools with geometries below 50 μm by conventional manufacturing methods becomes disproportional higher. Expensive serial finishing operations are required to achieve an adequate surface roughness combined with accurate geometry details. A novel approach for producing such tools is the use of advanced etching technologies for monocrystalline silicon that are well-established in the microsystems technology. High-precision vertical geometries with a width down to 5 μm are possible. The present study shows a novel concept using this potential for the blanking of thin copper foils with monocrystallline silicon as a tool material. A self-contained machine-tool with compact outer dimensions was designed to avoid tensile stresses in the brittle silicon punch by an accurate, careful alignment of the punch, die and metal foil. A microscopic analysis of the monocrystalline silicon punch shows appropriate properties regarding flank angle, edge geometry and surface quality for the blanking process. Using a monocrystalline silicon punch with a width of 70 μm blanking experiments on as-rolled copper foils with a thickness of 20 μm demonstrate the general applicability of this material for micro production processes.

  11. Highly sensitive capillary electrophoresis-mass spectrometry for rapid screening and accurate quantitation of drugs of abuse in urine.

    Science.gov (United States)

    Kohler, Isabelle; Schappler, Julie; Rudaz, Serge

    2013-05-30

    The combination of capillary electrophoresis (CE) and mass spectrometry (MS) is particularly well adapted to bioanalysis due to its high separation efficiency, selectivity, and sensitivity; its short analytical time; and its low solvent and sample consumption. For clinical and forensic toxicology, a two-step analysis is usually performed: first, a screening step for compound identification, and second, confirmation and/or accurate quantitation in cases of presumed positive results. In this study, a fast and sensitive CE-MS workflow was developed for the screening and quantitation of drugs of abuse in urine samples. A CE with a time-of-flight MS (CE-TOF/MS) screening method was developed using a simple urine dilution and on-line sample preconcentration with pH-mediated stacking. The sample stacking allowed for a high loading capacity (20.5% of the capillary length), leading to limits of detection as low as 2 ng mL(-1) for drugs of abuse. Compound quantitation of positive samples was performed by CE-MS/MS with a triple quadrupole MS equipped with an adapted triple-tube sprayer and an electrospray ionization (ESI) source. The CE-ESI-MS/MS method was validated for two model compounds, cocaine (COC) and methadone (MTD), according to the Guidance of the Food and Drug Administration. The quantitative performance was evaluated for selectivity, response function, the lower limit of quantitation, trueness, precision, and accuracy. COC and MTD detection in urine samples was determined to be accurate over the range of 10-1000 ng mL(-1) and 21-1000 ng mL(-1), respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Less accurate but more efficient family of search templates for detection of gravitational waves from inspiraling compact binaries

    International Nuclear Information System (INIS)

    Chronopoulos, Andreas E.; Apostolatos, Theocharis A.

    2001-01-01

    The network of interferometric detectors that is under construction at various locations on Earth is expected to start searching for gravitational waves in a few years. The number of search templates that is needed to be cross correlated with the noisy output of the detectors is a major issue since computing power capabilities are restricted. By choosing higher and higher post-Newtonian order expansions for the family of search templates we make sure that our filters are more accurate copies of the real waves that hit our detectors. However, this is not the only criterion for choosing a family of search templates. To make the process of detection as efficient as possible, one needs a family of templates with a relatively small number of members that manages to pick up any detectable signal with only a tiny reduction in signal-to-noise ratio. Evidently, one family is better than another if it accomplishes its goal with a smaller number of templates. Following the geometric language of Owen, we have studied the performance of the post 1.5 -Newtonian family of templates on detecting post 2 -Newtonian signals for binaries. Several technical issues arise from the fact that the two types of waveforms cannot be made to coincide by a suitable choice of parameters. In general, the parameter space of the signals is not identical with the parameter space of the templates, although in our case they are of the same dimension, and one has to take into account all such peculiarities before drawing any conclusion. An interesting result we have obtained is that the post 1.5 -Newtonian family of templates happens to be more economical for detecting post 2 -Newtonian signals than the perfectly accurate post 2 -Newtonian family of templates itself. The number of templates is reduced by 20-30%, depending on the acceptable level of reduction in signal-to-noise ratio due to discretization of the family of templates. This makes the post 1.5 -Newtonian family of templates more favorable

  13. Highly accurate thickness measurement of multi-layered automotive paints using terahertz technology

    Science.gov (United States)

    Krimi, Soufiene; Klier, Jens; Jonuscheit, Joachim; von Freymann, Georg; Urbansky, Ralph; Beigang, René

    2016-07-01

    In this contribution, we present a highly accurate approach for thickness measurements of multi-layered automotive paints using terahertz time domain spectroscopy in reflection geometry. The proposed method combines the benefits of a model-based material parameters extraction method to calibrate the paint coatings, a generalized Rouard's method to simulate the terahertz radiation behavior within arbitrary thin films, and the robustness of a powerful evolutionary optimization algorithm to increase the sensitivity of the minimum thickness measurement limit. Within the framework of this work, a self-calibration model is introduced, which takes into consideration the real industrial challenges such as the effect of wet-on-wet spray in the painting process.

  14. Highly accurate thickness measurement of multi-layered automotive paints using terahertz technology

    International Nuclear Information System (INIS)

    Krimi, Soufiene; Beigang, René; Klier, Jens; Jonuscheit, Joachim; Freymann, Georg von; Urbansky, Ralph

    2016-01-01

    In this contribution, we present a highly accurate approach for thickness measurements of multi-layered automotive paints using terahertz time domain spectroscopy in reflection geometry. The proposed method combines the benefits of a model-based material parameters extraction method to calibrate the paint coatings, a generalized Rouard's method to simulate the terahertz radiation behavior within arbitrary thin films, and the robustness of a powerful evolutionary optimization algorithm to increase the sensitivity of the minimum thickness measurement limit. Within the framework of this work, a self-calibration model is introduced, which takes into consideration the real industrial challenges such as the effect of wet-on-wet spray in the painting process.

  15. Accurate and emergent applications for high precision light small aerial remote sensing system

    International Nuclear Information System (INIS)

    Pei, Liu; Yingcheng, Li; Yanli, Xue; Xiaofeng, Sun; Qingwu, Hu

    2014-01-01

    In this paper, we focus on the successful applications of accurate and emergent surveying and mapping for high precision light small aerial remote sensing system. First, the remote sensing system structure and three integrated operation modes will be introduced. It can be combined to three operation modes depending on the application requirements. Second, we describe the preliminary results of a precision validation method for POS direct orientation in 1:500 mapping. Third, it presents two fast response mapping products- regional continuous three-dimensional model and digital surface model, taking the efficiency and accuracy evaluation of the two products as an important point. The precision of both products meets the 1:2 000 topographic map accuracy specifications in Pingdingshan area. In the end, conclusions and future work are summarized

  16. Accurate and emergent applications for high precision light small aerial remote sensing system

    Science.gov (United States)

    Pei, Liu; Yingcheng, Li; Yanli, Xue; Qingwu, Hu; Xiaofeng, Sun

    2014-03-01

    In this paper, we focus on the successful applications of accurate and emergent surveying and mapping for high precision light small aerial remote sensing system. First, the remote sensing system structure and three integrated operation modes will be introduced. It can be combined to three operation modes depending on the application requirements. Second, we describe the preliminary results of a precision validation method for POS direct orientation in 1:500 mapping. Third, it presents two fast response mapping products- regional continuous three-dimensional model and digital surface model, taking the efficiency and accuracy evaluation of the two products as an important point. The precision of both products meets the 1:2 000 topographic map accuracy specifications in Pingdingshan area. In the end, conclusions and future work are summarized.

  17. High channel count microphone array accurately and precisely localizes ultrasonic signals from freely-moving mice.

    Science.gov (United States)

    Warren, Megan R; Sangiamo, Daniel T; Neunuebel, Joshua P

    2018-03-01

    An integral component in the assessment of vocal behavior in groups of freely interacting animals is the ability to determine which animal is producing each vocal signal. This process is facilitated by using microphone arrays with multiple channels. Here, we made important refinements to a state-of-the-art microphone array based system used to localize vocal signals produced by freely interacting laboratory mice. Key changes to the system included increasing the number of microphones as well as refining the methodology for localizing and assigning vocal signals to individual mice. We systematically demonstrate that the improvements in the methodology for localizing mouse vocal signals led to an increase in the number of signals detected as well as the number of signals accurately assigned to an animal. These changes facilitated the acquisition of larger and more comprehensive data sets that better represent the vocal activity within an experiment. Furthermore, this system will allow more thorough analyses of the role that vocal signals play in social communication. We expect that such advances will broaden our understanding of social communication deficits in mouse models of neurological disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Fast and accurate: high-speed metrological large-range AFM for surface and nanometrology

    Science.gov (United States)

    Dai, Gaoliang; Koenders, Ludger; Fluegge, Jens; Hemmleb, Matthias

    2018-05-01

    Low measurement speed remains a major shortcoming of the scanning probe microscopic technique. It not only leads to a low measurement throughput, but a significant measurement drift over the long measurement time needed (up to hours or even days). To overcome this challenge, PTB, the national metrology institute of Germany, has developed a high-speed metrological large-range atomic force microscope (HS Met. LR-AFM) capable of measuring speeds up to 1 mm s‑1. This paper has introduced the design concept in detail. After modelling scanning probe microscopic measurements, our results suggest that the signal spectrum of the surface to be measured is the spatial spectrum of the surface scaled by the scanning speed. The higher the scanning speed , the broader the spectrum to be measured. To realise an accurate HS Met. LR-AFM, our solution is to combine different stages/sensors synchronously in measurements, which provide a much larger spectrum area for high-speed measurement capability. Two application examples have been demonstrated. The first is a new concept called reference areal surface metrology. Using the developed HS Met. LR-AFM, surfaces are measured accurately and traceably at a speed of 500 µm s‑1 and the results are applied as a reference 3D data map of the surfaces. By correlating the reference 3D data sets and 3D data sets of tools under calibration, which are measured at the same surface, it has the potential to comprehensively characterise the tools, for instance, the spectrum properties of the tools. The investigation results of two commercial confocal microscopes are demonstrated, indicating very promising results. The second example is the calibration of a kind of 3D nano standard, which has spatially distributed landmarks, i.e. special unique features defined by 3D-coordinates. Experimental investigations confirmed that the calibration accuracy is maintained at a measurement speed of 100 µm s‑1, which improves the calibration efficiency by a

  19. Creation of an Accurate Algorithm to Detect Snellen Best Documented Visual Acuity from Ophthalmology Electronic Health Record Notes.

    Science.gov (United States)

    Mbagwu, Michael; French, Dustin D; Gill, Manjot; Mitchell, Christopher; Jackson, Kathryn; Kho, Abel; Bryar, Paul J

    2016-05-04

    Visual acuity is the primary measure used in ophthalmology to determine how well a patient can see. Visual acuity for a single eye may be recorded in multiple ways for a single patient visit (eg, Snellen vs. Jäger units vs. font print size), and be recorded for either distance or near vision. Capturing the best documented visual acuity (BDVA) of each eye in an individual patient visit is an important step for making electronic ophthalmology clinical notes useful in research. Currently, there is limited methodology for capturing BDVA in an efficient and accurate manner from electronic health record (EHR) notes. We developed an algorithm to detect BDVA for right and left eyes from defined fields within electronic ophthalmology clinical notes. We designed an algorithm to detect the BDVA from defined fields within 295,218 ophthalmology clinical notes with visual acuity data present. About 5668 unique responses were identified and an algorithm was developed to map all of the unique responses to a structured list of Snellen visual acuities. Visual acuity was captured from a total of 295,218 ophthalmology clinical notes during the study dates. The algorithm identified all visual acuities in the defined visual acuity section for each eye and returned a single BDVA for each eye. A clinician chart review of 100 random patient notes showed a 99% accuracy detecting BDVA from these records and 1% observed error. Our algorithm successfully captures best documented Snellen distance visual acuity from ophthalmology clinical notes and transforms a variety of inputs into a structured Snellen equivalent list. Our work, to the best of our knowledge, represents the first attempt at capturing visual acuity accurately from large numbers of electronic ophthalmology notes. Use of this algorithm can benefit research groups interested in assessing visual acuity for patient centered outcome. All codes used for this study are currently available, and will be made available online at https://phekb.org.

  20. A unique charge-coupled device/xenon arc lamp based imaging system for the accurate detection and quantitation of multicolour fluorescence.

    Science.gov (United States)

    Spibey, C A; Jackson, P; Herick, K

    2001-03-01

    In recent years the use of fluorescent dyes in biological applications has dramatically increased. The continual improvement in the capabilities of these fluorescent dyes demands increasingly sensitive detection systems that provide accurate quantitation over a wide linear dynamic range. In the field of proteomics, the detection, quantitation and identification of very low abundance proteins are of extreme importance in understanding cellular processes. Therefore, the instrumentation used to acquire an image of such samples, for spot picking and identification by mass spectrometry, must be sensitive enough to be able, not only, to maximise the sensitivity and dynamic range of the staining dyes but, as importantly, adapt to the ever changing portfolio of fluorescent dyes as they become available. Just as the available fluorescent probes are improving and evolving so are the users application requirements. Therefore, the instrumentation chosen must be flexible to address and adapt to those changing needs. As a result, a highly competitive market for the supply and production of such dyes and the instrumentation for their detection and quantitation have emerged. The instrumentation currently available is based on either laser/photomultiplier tube (PMT) scanning or lamp/charge-coupled device (CCD) based mechanisms. This review briefly discusses the advantages and disadvantages of both System types for fluorescence imaging, gives a technical overview of CCD technology and describes in detail a unique xenon/are lamp CCD based instrument, from PerkinElmer Life Sciences. The Wallac-1442 ARTHUR is unique in its ability to scan both large areas at high resolution and give accurate selectable excitation over the whole of the UV/visible range. It operates by filtering both the excitation and emission wavelengths, providing optimal and accurate measurement and quantitation of virtually any available dye and allows excellent spectral resolution between different fluorophores

  1. Accurate Point-of-Care Detection of Ruptured Fetal Membranes: Improved Diagnostic Performance Characteristics with a Monoclonal/Polyclonal Immunoassay

    Directory of Open Access Journals (Sweden)

    Linda C. Rogers

    2016-01-01

    Full Text Available Objective Accurate and timely diagnosis of rupture of membranes (ROM is imperative to allow for gestational age-specific interventions. This study compared the diagnostic performance characteristics between two methods used for the detection of ROM as measured in the same patient. Methods Vaginal secretions were evaluated using the conventional fern test as well as a point-of-care monoclonal/polyclonal immunoassay test (ROM Plus® in 75 pregnant patients who presented to labor and delivery with complaints of leaking amniotic fluid. Both tests were compared to analytical confirmation of ROM using three external laboratory tests. Diagnostic performance characteristics were calculated including sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV, and accuracy. Results Diagnostic performance characteristics uniformly favored ROM detection using the immunoassay test compared to the fern test: sensitivity (100% vs. 77.8%, specificity (94.8% vs. 79.3%, PPV (75% vs. 36.8%, NPV (100% vs. 95.8%, and accuracy (95.5% vs. 79.1%. Conclusions The point-of-care immunoassay test provides improved diagnostic accuracy for the detection of ROM compared to fern testing. It has the potential of improving patient management decisions, thereby minimizing serious complications and perinatal morbidity.

  2. Maximized Inter-Class Weighted Mean for Fast and Accurate Mitosis Cells Detection in Breast Cancer Histopathology Images.

    Science.gov (United States)

    Nateghi, Ramin; Danyali, Habibollah; Helfroush, Mohammad Sadegh

    2017-08-14

    Based on the Nottingham criteria, the number of mitosis cells in histopathological slides is an important factor in diagnosis and grading of breast cancer. For manual grading of mitosis cells, histopathology slides of the tissue are examined by pathologists at 40× magnification for each patient. This task is very difficult and time-consuming even for experts. In this paper, a fully automated method is presented for accurate detection of mitosis cells in histopathology slide images. First a method based on maximum-likelihood is employed for segmentation and extraction of mitosis cell. Then a novel Maximized Inter-class Weighted Mean (MIWM) method is proposed that aims at reducing the number of extracted non-mitosis candidates that results in reducing the false positive mitosis detection rate. Finally, segmented candidates are classified into mitosis and non-mitosis classes by using a support vector machine (SVM) classifier. Experimental results demonstrate a significant improvement in accuracy of mitosis cells detection in different grades of breast cancer histopathological images.

  3. Pairagon: a highly accurate, HMM-based cDNA-to-genome aligner.

    Science.gov (United States)

    Lu, David V; Brown, Randall H; Arumugam, Manimozhiyan; Brent, Michael R

    2009-07-01

    The most accurate way to determine the intron-exon structures in a genome is to align spliced cDNA sequences to the genome. Thus, cDNA-to-genome alignment programs are a key component of most annotation pipelines. The scoring system used to choose the best alignment is a primary determinant of alignment accuracy, while heuristics that prevent consideration of certain alignments are a primary determinant of runtime and memory usage. Both accuracy and speed are important considerations in choosing an alignment algorithm, but scoring systems have received much less attention than heuristics. We present Pairagon, a pair hidden Markov model based cDNA-to-genome alignment program, as the most accurate aligner for sequences with high- and low-identity levels. We conducted a series of experiments testing alignment accuracy with varying sequence identity. We first created 'perfect' simulated cDNA sequences by splicing the sequences of exons in the reference genome sequences of fly and human. The complete reference genome sequences were then mutated to various degrees using a realistic mutation simulator and the perfect cDNAs were aligned to them using Pairagon and 12 other aligners. To validate these results with natural sequences, we performed cross-species alignment using orthologous transcripts from human, mouse and rat. We found that aligner accuracy is heavily dependent on sequence identity. For sequences with 100% identity, Pairagon achieved accuracy levels of >99.6%, with one quarter of the errors of any other aligner. Furthermore, for human/mouse alignments, which are only 85% identical, Pairagon achieved 87% accuracy, higher than any other aligner. Pairagon source and executables are freely available at http://mblab.wustl.edu/software/pairagon/

  4. Raman spectroscopy for highly accurate estimation of the age of refrigerated porcine muscle

    Science.gov (United States)

    Timinis, Constantinos; Pitris, Costas

    2016-03-01

    The high water content of meat, combined with all the nutrients it contains, make it vulnerable to spoilage at all stages of production and storage even when refrigerated at 5 °C. A non-destructive and in situ tool for meat sample testing, which could provide an accurate indication of the storage time of meat, would be very useful for the control of meat quality as well as for consumer safety. The proposed solution is based on Raman spectroscopy which is non-invasive and can be applied in situ. For the purposes of this project, 42 meat samples from 14 animals were obtained and three Raman spectra per sample were collected every two days for two weeks. The spectra were subsequently processed and the sample age was calculated using a set of linear differential equations. In addition, the samples were classified in categories corresponding to the age in 2-day steps (i.e., 0, 2, 4, 6, 8, 10, 12 or 14 days old), using linear discriminant analysis and cross-validation. Contrary to other studies, where the samples were simply grouped into two categories (higher or lower quality, suitable or unsuitable for human consumption, etc.), in this study, the age was predicted with a mean error of ~ 1 day (20%) or classified, in 2-day steps, with 100% accuracy. Although Raman spectroscopy has been used in the past for the analysis of meat samples, the proposed methodology has resulted in a prediction of the sample age far more accurately than any report in the literature.

  5. Multilevel Thresholding Method Based on Electromagnetism for Accurate Brain MRI Segmentation to Detect White Matter, Gray Matter, and CSF

    Directory of Open Access Journals (Sweden)

    G. Sandhya

    2017-01-01

    Full Text Available This work explains an advanced and accurate brain MRI segmentation method. MR brain image segmentation is to know the anatomical structure, to identify the abnormalities, and to detect various tissues which help in treatment planning prior to radiation therapy. This proposed technique is a Multilevel Thresholding (MT method based on the phenomenon of Electromagnetism and it segments the image into three tissues such as White Matter (WM, Gray Matter (GM, and CSF. The approach incorporates skull stripping and filtering using anisotropic diffusion filter in the preprocessing stage. This thresholding method uses the force of attraction-repulsion between the charged particles to increase the population. It is the combination of Electromagnetism-Like optimization algorithm with the Otsu and Kapur objective functions. The results obtained by using the proposed method are compared with the ground-truth images and have given best values for the measures sensitivity, specificity, and segmentation accuracy. The results using 10 MR brain images proved that the proposed method has accurately segmented the three brain tissues compared to the existing segmentation methods such as K-means, fuzzy C-means, OTSU MT, Particle Swarm Optimization (PSO, Bacterial Foraging Algorithm (BFA, Genetic Algorithm (GA, and Fuzzy Local Gaussian Mixture Model (FLGMM.

  6. Accurate determination of high-risk coronary lesion type by multidetector cardiac computed tomography.

    Science.gov (United States)

    Alasnag, Mirvat; Umakanthan, Branavan; Foster, Gary P

    2008-07-01

    Coronary arteriography (CA) is the standard method to image coronary lesions. Multidetector cardiac computerized tomography (MDCT) provides high-resolution images of coronary arteries, allowing a noninvasive alternative to determine lesion type. To date, no studies have assessed the ability of MDCT to categorize coronary lesion types. The objective of this study was to determine the accuracy of lesion type categorization by MDCT using CA as a reference standard. Patients who underwent both MDCT and CA within 2 months of each other were enrolled. MDCT and CA images were reviewed in a blinded fashion. Lesions were categorized according to the SCAI classification system (Types I-IV). The origin, proximal and middle segments of the major arteries were analyzed. Each segment comprised a data point for comparison. Analysis was performed using the Spearman Correlation Test. Four hundred eleven segments were studied, of which 110 had lesions. The lesion distribution was as follows: 35 left anterior descending (LAD), 29 circumflex (Cx), 31 right coronary artery (RCA), 2 ramus intermedius, 8 diagonal, 4 obtuse marginal and 2 left internal mammary arteries. Correlations between MDCT and CA were significant in all major vessels (LAD, Cx, RCA) (p < 0.001). The overall correlation coefficient was 0.67. Concordance was strong for lesion Types II-IV (97%) and poor for Type I (30%). High-risk coronary lesion types can be accurately categorized by MDCT. This ability may allow MDCT to play an important noninvasive role in the planning of coronary interventions.

  7. Accurate, high-throughput typing of copy number variation using paralogue ratios from dispersed repeats.

    Science.gov (United States)

    Armour, John A L; Palla, Raquel; Zeeuwen, Patrick L J M; den Heijer, Martin; Schalkwijk, Joost; Hollox, Edward J

    2007-01-01

    Recent work has demonstrated an unexpected prevalence of copy number variation in the human genome, and has highlighted the part this variation may play in predisposition to common phenotypes. Some important genes vary in number over a high range (e.g. DEFB4, which commonly varies between two and seven copies), and have posed formidable technical challenges for accurate copy number typing, so that there are no simple, cheap, high-throughput approaches suitable for large-scale screening. We have developed a simple comparative PCR method based on dispersed repeat sequences, using a single pair of precisely designed primers to amplify products simultaneously from both test and reference loci, which are subsequently distinguished and quantified via internal sequence differences. We have validated the method for the measurement of copy number at DEFB4 by comparison of results from >800 DNA samples with copy number measurements by MAPH/REDVR, MLPA and array-CGH. The new Paralogue Ratio Test (PRT) method can require as little as 10 ng genomic DNA, appears to be comparable in accuracy to the other methods, and for the first time provides a rapid, simple and inexpensive method for copy number analysis, suitable for application to typing thousands of samples in large case-control association studies.

  8. HIGHLY-ACCURATE MODEL ORDER REDUCTION TECHNIQUE ON A DISCRETE DOMAIN

    Directory of Open Access Journals (Sweden)

    L. D. Ribeiro

    2015-09-01

    Full Text Available AbstractIn this work, we present a highly-accurate technique of model order reduction applied to staged processes. The proposed method reduces the dimension of the original system based on null values of moment-weighted sums of heat and mass balance residuals on real stages. To compute these sums of weighted residuals, a discrete form of Gauss-Lobatto quadrature was developed, allowing a high degree of accuracy in these calculations. The locations where the residuals are cancelled vary with time and operating conditions, characterizing a desirable adaptive nature of this technique. Balances related to upstream and downstream devices (such as condenser, reboiler, and feed tray of a distillation column are considered as boundary conditions of the corresponding difference-differential equations system. The chosen number of moments is the dimension of the reduced model being much lower than the dimension of the complete model and does not depend on the size of the original model. Scaling of the discrete independent variable related with the stages was crucial for the computational implementation of the proposed method, avoiding accumulation of round-off errors present even in low-degree polynomial approximations in the original discrete variable. Dynamical simulations of distillation columns were carried out to check the performance of the proposed model order reduction technique. The obtained results show the superiority of the proposed procedure in comparison with the orthogonal collocation method.

  9. Automatically high accurate and efficient photomask defects management solution for advanced lithography manufacture

    Science.gov (United States)

    Zhu, Jun; Chen, Lijun; Ma, Lantao; Li, Dejian; Jiang, Wei; Pan, Lihong; Shen, Huiting; Jia, Hongmin; Hsiang, Chingyun; Cheng, Guojie; Ling, Li; Chen, Shijie; Wang, Jun; Liao, Wenkui; Zhang, Gary

    2014-04-01

    Defect review is a time consuming job. Human error makes result inconsistent. The defects located on don't care area would not hurt the yield and no need to review them such as defects on dark area. However, critical area defects can impact yield dramatically and need more attention to review them such as defects on clear area. With decrease in integrated circuit dimensions, mask defects are always thousands detected during inspection even more. Traditional manual or simple classification approaches are unable to meet efficient and accuracy requirement. This paper focuses on automatic defect management and classification solution using image output of Lasertec inspection equipment and Anchor pattern centric image process technology. The number of mask defect found during an inspection is always in the range of thousands or even more. This system can handle large number defects with quick and accurate defect classification result. Our experiment includes Die to Die and Single Die modes. The classification accuracy can reach 87.4% and 93.3%. No critical or printable defects are missing in our test cases. The missing classification defects are 0.25% and 0.24% in Die to Die mode and Single Die mode. This kind of missing rate is encouraging and acceptable to apply on production line. The result can be output and reloaded back to inspection machine to have further review. This step helps users to validate some unsure defects with clear and magnification images when captured images can't provide enough information to make judgment. This system effectively reduces expensive inline defect review time. As a fully inline automated defect management solution, the system could be compatible with current inspection approach and integrated with optical simulation even scoring function and guide wafer level defect inspection.

  10. Validation of a method for accurate and highly reproducible quantification of brain dopamine transporter SPECT studies

    DEFF Research Database (Denmark)

    Jensen, Peter S; Ziebell, Morten; Skouboe, Glenna

    2011-01-01

    In nuclear medicine brain imaging, it is important to delineate regions of interest (ROIs) so that the outcome is both accurate and reproducible. The purpose of this study was to validate a new time-saving algorithm (DATquan) for accurate and reproducible quantification of the striatal dopamine t...... transporter (DAT) with appropriate radioligands and SPECT and without the need for structural brain scanning....

  11. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service

    Directory of Open Access Journals (Sweden)

    Han Zou

    2016-02-01

    Full Text Available The location and contextual status (indoor or outdoor is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS for individuals. In addition, optimizations of building management systems (BMS, such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  12. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service.

    Science.gov (United States)

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-02-22

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  13. Approaches to the accurate characterization of high purity metal fluorides and fluoride glasses

    Science.gov (United States)

    Beary, E. S.; Paulsen, P. J.; Rains, T. C.; Ewing, K. J.; Jaganathan, J.; Aggarwal, I.

    1990-11-01

    The analytical challenges posed by the measurement of trace contaminants in high purity metal fluorides require that innovative chemical preparation procedures be used to enhance existing instrumental techniques. The instrumental techniques used to analyze these difficult matrices must be sensitive enough to detect extremely low levels of trace impurities, and the background interferences derived from the matrix (metal fluoride or glass) must be minimized. A survey of analytical techniques that have the necessary characteristics to analyze these materials will be given. In addition, means of controlling the chemical blank will be presented. Mass and atomic spectrometric techniques will be discussed, specifically graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma-mass spectrometry (ICP-MS). Analytical procedures using GFAAS and ICP-MS have been developed to determine sub ppb (part per billion) levels of contaminants in high purity fluoride materials.

  14. Continuous Digital Light Processing (cDLP): Highly Accurate Additive Manufacturing of Tissue Engineered Bone Scaffolds.

    Science.gov (United States)

    Dean, David; Jonathan, Wallace; Siblani, Ali; Wang, Martha O; Kim, Kyobum; Mikos, Antonios G; Fisher, John P

    2012-03-01

    Highly accurate rendering of the external and internal geometry of bone tissue engineering scaffolds effects fit at the defect site, loading of internal pore spaces with cells, bioreactor-delivered nutrient and growth factor circulation, and scaffold resorption. It may be necessary to render resorbable polymer scaffolds with 50 μm or less accuracy to achieve these goals. This level of accuracy is available using Continuous Digital Light processing (cDLP) which utilizes a DLP(®) (Texas Instruments, Dallas, TX) chip. One such additive manufacturing device is the envisionTEC (Ferndale, MI) Perfactory(®). To use cDLP we integrate a photo-crosslinkable polymer, a photo-initiator, and a biocompatible dye. The dye attenuates light, thereby limiting the depth of polymerization. In this study we fabricated scaffolds using the well-studied resorbable polymer, poly(propylene fumarate) (PPF), titanium dioxide (TiO(2)) as a dye, Irgacure(®) 819 (BASF [Ciba], Florham Park, NJ) as an initiator, and diethyl fumarate as a solvent to control viscosity.

  15. Development of highly accurate approximate scheme for computing the charge transfer integral

    Energy Technology Data Exchange (ETDEWEB)

    Pershin, Anton; Szalay, Péter G. [Laboratory for Theoretical Chemistry, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, H-1518 Budapest (Hungary)

    2015-08-21

    The charge transfer integral is a key parameter required by various theoretical models to describe charge transport properties, e.g., in organic semiconductors. The accuracy of this important property depends on several factors, which include the level of electronic structure theory and internal simplifications of the applied formalism. The goal of this paper is to identify the performance of various approximate approaches of the latter category, while using the high level equation-of-motion coupled cluster theory for the electronic structure. The calculations have been performed on the ethylene dimer as one of the simplest model systems. By studying different spatial perturbations, it was shown that while both energy split in dimer and fragment charge difference methods are equivalent with the exact formulation for symmetrical displacements, they are less efficient when describing transfer integral along the asymmetric alteration coordinate. Since the “exact” scheme was found computationally expensive, we examine the possibility to obtain the asymmetric fluctuation of the transfer integral by a Taylor expansion along the coordinate space. By exploring the efficiency of this novel approach, we show that the Taylor expansion scheme represents an attractive alternative to the “exact” calculations due to a substantial reduction of computational costs, when a considerably large region of the potential energy surface is of interest. Moreover, we show that the Taylor expansion scheme, irrespective of the dimer symmetry, is very accurate for the entire range of geometry fluctuations that cover the space the molecule accesses at room temperature.

  16. A high quality Arabidopsis transcriptome for accurate transcript-level analysis of alternative splicing

    KAUST Repository

    Zhang, Runxuan

    2017-04-05

    Alternative splicing generates multiple transcript and protein isoforms from the same gene and thus is important in gene expression regulation. To date, RNA-sequencing (RNA-seq) is the standard method for quantifying changes in alternative splicing on a genome-wide scale. Understanding the current limitations of RNA-seq is crucial for reliable analysis and the lack of high quality, comprehensive transcriptomes for most species, including model organisms such as Arabidopsis, is a major constraint in accurate quantification of transcript isoforms. To address this, we designed a novel pipeline with stringent filters and assembled a comprehensive Reference Transcript Dataset for Arabidopsis (AtRTD2) containing 82,190 non-redundant transcripts from 34 212 genes. Extensive experimental validation showed that AtRTD2 and its modified version, AtRTD2-QUASI, for use in Quantification of Alternatively Spliced Isoforms, outperform other available transcriptomes in RNA-seq analysis. This strategy can be implemented in other species to build a pipeline for transcript-level expression and alternative splicing analyses.

  17. A high quality Arabidopsis transcriptome for accurate transcript-level analysis of alternative splicing

    KAUST Repository

    Zhang, Runxuan; Calixto, Cristiane  P.  G.; Marquez, Yamile; Venhuizen, Peter; Tzioutziou, Nikoleta A.; Guo, Wenbin; Spensley, Mark; Entizne, Juan Carlos; Lewandowska, Dominika; ten  Have, Sara; Frei  dit  Frey, Nicolas; Hirt, Heribert; James, Allan B.; Nimmo, Hugh G.; Barta, Andrea; Kalyna, Maria; Brown, John  W.  S.

    2017-01-01

    Alternative splicing generates multiple transcript and protein isoforms from the same gene and thus is important in gene expression regulation. To date, RNA-sequencing (RNA-seq) is the standard method for quantifying changes in alternative splicing on a genome-wide scale. Understanding the current limitations of RNA-seq is crucial for reliable analysis and the lack of high quality, comprehensive transcriptomes for most species, including model organisms such as Arabidopsis, is a major constraint in accurate quantification of transcript isoforms. To address this, we designed a novel pipeline with stringent filters and assembled a comprehensive Reference Transcript Dataset for Arabidopsis (AtRTD2) containing 82,190 non-redundant transcripts from 34 212 genes. Extensive experimental validation showed that AtRTD2 and its modified version, AtRTD2-QUASI, for use in Quantification of Alternatively Spliced Isoforms, outperform other available transcriptomes in RNA-seq analysis. This strategy can be implemented in other species to build a pipeline for transcript-level expression and alternative splicing analyses.

  18. Achieving accurate simulations of urban impacts on ozone at high resolution

    International Nuclear Information System (INIS)

    Li, J; Georgescu, M; Mahalov, A; Moustaoui, M; Hyde, P

    2014-01-01

    The effects of urbanization on ozone levels have been widely investigated over cities primarily located in temperate and/or humid regions. In this study, nested WRF-Chem simulations with a finest grid resolution of 1 km are conducted to investigate ozone concentrations [O 3 ] due to urbanization within cities in arid/semi-arid environments. First, a method based on a shape preserving Monotonic Cubic Interpolation (MCI) is developed and used to downscale anthropogenic emissions from the 4 km resolution 2005 National Emissions Inventory (NEI05) to the finest model resolution of 1 km. Using the rapidly expanding Phoenix metropolitan region as the area of focus, we demonstrate the proposed MCI method achieves ozone simulation results with appreciably improved correspondence to observations relative to the default interpolation method of the WRF-Chem system. Next, two additional sets of experiments are conducted, with the recommended MCI approach, to examine impacts of urbanization on ozone production: (1) the urban land cover is included (i.e., urbanization experiments) and, (2) the urban land cover is replaced with the region’s native shrubland. Impacts due to the presence of the built environment on [O 3 ] are highly heterogeneous across the metropolitan area. Increased near surface [O 3 ] due to urbanization of 10–20 ppb is predominantly a nighttime phenomenon while simulated impacts during daytime are negligible. Urbanization narrows the daily [O 3 ] range (by virtue of increasing nighttime minima), an impact largely due to the region’s urban heat island. Our results demonstrate the importance of the MCI method for accurate representation of the diurnal profile of ozone, and highlight its utility for high-resolution air quality simulations for urban areas. (letter)

  19. Highly accurate sequence imputation enables precise QTL mapping in Brown Swiss cattle.

    Science.gov (United States)

    Frischknecht, Mirjam; Pausch, Hubert; Bapst, Beat; Signer-Hasler, Heidi; Flury, Christine; Garrick, Dorian; Stricker, Christian; Fries, Ruedi; Gredler-Grandl, Birgit

    2017-12-29

    Within the last few years a large amount of genomic information has become available in cattle. Densities of genomic information vary from a few thousand variants up to whole genome sequence information. In order to combine genomic information from different sources and infer genotypes for a common set of variants, genotype imputation is required. In this study we evaluated the accuracy of imputation from high density chips to whole genome sequence data in Brown Swiss cattle. Using four popular imputation programs (Beagle, FImpute, Impute2, Minimac) and various compositions of reference panels, the accuracy of the imputed sequence variant genotypes was high and differences between the programs and scenarios were small. We imputed sequence variant genotypes for more than 1600 Brown Swiss bulls and performed genome-wide association studies for milk fat percentage at two stages of lactation. We found one and three quantitative trait loci for early and late lactation fat content, respectively. Known causal variants that were imputed from the sequenced reference panel were among the most significantly associated variants of the genome-wide association study. Our study demonstrates that whole-genome sequence information can be imputed at high accuracy in cattle populations. Using imputed sequence variant genotypes in genome-wide association studies may facilitate causal variant detection.

  20. Accurate molecular diagnosis of phenylketonuria and tetrahydrobiopterin-deficient hyperphenylalaninemias using high-throughput targeted sequencing

    Science.gov (United States)

    Trujillano, Daniel; Perez, Belén; González, Justo; Tornador, Cristian; Navarrete, Rosa; Escaramis, Georgia; Ossowski, Stephan; Armengol, Lluís; Cornejo, Verónica; Desviat, Lourdes R; Ugarte, Magdalena; Estivill, Xavier

    2014-01-01

    Genetic diagnostics of phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficient hyperphenylalaninemia (BH4DH) rely on methods that scan for known mutations or on laborious molecular tools that use Sanger sequencing. We have implemented a novel and much more efficient strategy based on high-throughput multiplex-targeted resequencing of four genes (PAH, GCH1, PTS, and QDPR) that, when affected by loss-of-function mutations, cause PKU and BH4DH. We have validated this approach in a cohort of 95 samples with the previously known PAH, GCH1, PTS, and QDPR mutations and one control sample. Pooled barcoded DNA libraries were enriched using a custom NimbleGen SeqCap EZ Choice array and sequenced using a HiSeq2000 sequencer. The combination of several robust bioinformatics tools allowed us to detect all known pathogenic mutations (point mutations, short insertions/deletions, and large genomic rearrangements) in the 95 samples, without detecting spurious calls in these genes in the control sample. We then used the same capture assay in a discovery cohort of 11 uncharacterized HPA patients using a MiSeq sequencer. In addition, we report the precise characterization of the breakpoints of four genomic rearrangements in PAH, including a novel deletion of 899 bp in intron 3. Our study is a proof-of-principle that high-throughput-targeted resequencing is ready to substitute classical molecular methods to perform differential genetic diagnosis of hyperphenylalaninemias, allowing the establishment of specifically tailored treatments a few days after birth. PMID:23942198

  1. In-depth glycoproteomic characterization of γ-conglutin by high-resolution accurate mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Silvia Schiarea

    Full Text Available The molecular characterization of bioactive food components is necessary for understanding the mechanisms of their beneficial or detrimental effects on human health. This study focused on γ-conglutin, a well-known lupin seed N-glycoprotein with health-promoting properties and controversial allergenic potential. Given the importance of N-glycosylation for the functional and structural characteristics of proteins, we studied the purified protein by a mass spectrometry-based glycoproteomic approach able to identify the structure, micro-heterogeneity and attachment site of the bound N-glycan(s, and to provide extensive coverage of the protein sequence. The peptide/N-glycopeptide mixtures generated by enzymatic digestion (with or without N-deglycosylation were analyzed by high-resolution accurate mass liquid chromatography-multi-stage mass spectrometry. The four main micro-heterogeneous variants of the single N-glycan bound to γ-conglutin were identified as Man2(Xyl (Fuc GlcNAc2, Man3(Xyl (Fuc GlcNAc2, GlcNAcMan3(Xyl (Fuc GlcNAc2 and GlcNAc 2Man3(Xyl (Fuc GlcNAc2. These carry both core β1,2-xylose and core α1-3-fucose (well known Cross-Reactive Carbohydrate Determinants, but corresponding fucose-free variants were also identified as minor components. The N-glycan was proven to reside on Asn131, one of the two potential N-glycosylation sites. The extensive coverage of the γ-conglutin amino acid sequence suggested three alternative N-termini of the small subunit, that were later confirmed by direct-infusion Orbitrap mass spectrometry analysis of the intact subunit.

  2. Accurate determination of non-metallic impurities in high purity tetramethylammonium hydroxide using inductively coupled plasma tandem mass spectrometry

    Science.gov (United States)

    Fu, Liang; Xie, Hualin; Shi, Shuyun; Chen, Xiaoqing

    2018-06-01

    The content of non-metallic impurities in high-purity tetramethylammonium hydroxide (HPTMAH) aqueous solution has an important influence on the yield, electrical properties and reliability of the integrated circuit during the process of chip etching and cleaning. Therefore, an efficient analytical method to directly quantify the content of non-metallic impurities in HPTMAH aqueous solutions is necessary. The present study was aimed to develop a novel method that can accurately determine seven non-metallic impurities (B, Si, P, S, Cl, As, and Se) in an aqueous solution of HPTMAH by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The samples were measured using a direct injection method. In the MS/MS mode, oxygen and hydrogen were used as reaction gases in the octopole reaction system (ORS) to eliminate mass spectral interferences during the analytical process. The detection limits of B, Si, P, S, Cl, As, and Se were 0.31, 0.48, 0.051, 0.27, 3.10, 0.008, and 0.005 μg L-1, respectively. The samples were analyzed by the developed method and the sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) was used for contrastive analysis. The values of these seven elements measured using ICP-MS/MS were consistent with those measured by SF-ICP-MS. The proposed method can be utilized to analyze non-metallic impurities in HPTMAH aqueous solution. Table S2 Multiple potential interferences on the analytes. Table S3 Parameters of calibration curve and the detection limit (DL). Table S4 Results obtained for 25% concentration high-purity grade TMAH aqueous solution samples (μg L-1, mean ± standard deviation, n = 10).

  3. Unenhanced breast MRI (STIR, T2-weighted TSE, DWIBS): An accurate and alternative strategy for detecting and differentiating breast lesions.

    Science.gov (United States)

    Telegrafo, Michele; Rella, Leonarda; Stabile Ianora, Amato Antonio; Angelelli, Giuseppe; Moschetta, Marco

    2015-10-01

    To assess the role of STIR, T2-weighted TSE and DWIBS sequences for detecting and characterizing breast lesions and to compare unenhanced (UE)-MRI results with contrast-enhanced (CE)-MRI and histological findings, having the latter as the reference standard. Two hundred eighty consecutive patients (age range, 27-73 years; mean age±standard deviation (SD), 48.8±9.8years) underwent MR examination with a diagnostic protocol including STIR, T2-weighted TSE, THRIVE and DWIBS sequences. Two radiologists blinded to both dynamic sequences and histological findings evaluated in consensus STIR, T2-weighted TSE and DWIBS sequences and after two weeks CE-MRI images searching for breast lesions. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for UE-MRI and CE-MRI were calculated. UE-MRI results were also compared with CE- MRI. UE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 94%, 79%, 86%, 79% and 94%, respectively. CE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 98%, 83%, 90%, 84% and 98%, respectively. No statistically significant difference between UE-MRI and CE-MRI was found. Breast UE-MRI could represent an accurate diagnostic tool and a valid alternative to CE-MRI for evaluating breast lesions. STIR and DWIBS sequences allow to detect breast lesions while T2-weighted TSE sequences and ADC values could be useful for lesion characterization. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Histamine quantification in human plasma using high resolution accurate mass LC-MS technology.

    Science.gov (United States)

    Laurichesse, Mathieu; Gicquel, Thomas; Moreau, Caroline; Tribut, Olivier; Tarte, Karin; Morel, Isabelle; Bendavid, Claude; Amé-Thomas, Patricia

    2016-01-01

    Histamine (HA) is a small amine playing an important role in anaphylactic reactions. In order to identify and quantify HA in plasma matrix, different methods have been developed but present several disadvantages. Here, we developed an alternative method using liquid chromatography coupled with an ultra-high resolution and accurate mass instrument, Q Exactive™ (Thermo Fisher) (LCHRMS). The method includes a protein precipitation of plasma samples spiked with HA-d4 as internal standard (IS). LC separation was performed on a C18 Accucore column (100∗2.1mm, 2.6μm) using a mobile phase containing nonafluoropentanoic acid (3nM) and acetonitrile with 0.1% (v/v) formic acid on gradient mode. Separation of analytes was obtained within 10min. Analysis was performed from full scan mode and targeted MS2 mode using a 5ppm mass window. Ion transitions monitored for targeted MS2 mode were 112.0869>95.0607m/z for HA and 116.1120>99.0855m/z for HA-d4. Calibration curves were obtained by adding standard calibration dilution at 1 to 180nM in TrisBSA. Elution of HA and IS occurred at 4.1min. The method was validated over a range of concentrations from 1nM to 100nM. The intra- and inter-run precisions were <15% for quality controls. Human plasma samples from 30 patients were analyzed by LCHRMS, and the results were highly correlated with those obtained using the gold standard radioimmunoassay (RIA) method. Overall, we demonstrate here that LCHRMS is a sensitive method for histamine quantification in biological human plasmas, suitable for routine use in medical laboratories. In addition, LCHRMS is less time-consuming than RIA, avoids the use of radioactivity, and could then be considered as an alternative quantitative method. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  5. A Dual-Mode Large-Arrayed CMOS ISFET Sensor for Accurate and High-Throughput pH Sensing in Biomedical Diagnosis.

    Science.gov (United States)

    Huang, Xiwei; Yu, Hao; Liu, Xu; Jiang, Yu; Yan, Mei; Wu, Dongping

    2015-09-01

    The existing ISFET-based DNA sequencing detects hydrogen ions released during the polymerization of DNA strands on microbeads, which are scattered into microwell array above the ISFET sensor with unknown distribution. However, false pH detection happens at empty microwells due to crosstalk from neighboring microbeads. In this paper, a dual-mode CMOS ISFET sensor is proposed to have accurate pH detection toward DNA sequencing. Dual-mode sensing, optical and chemical modes, is realized by integrating a CMOS image sensor (CIS) with ISFET pH sensor, and is fabricated in a standard 0.18-μm CIS process. With accurate determination of microbead physical locations with CIS pixel by contact imaging, the dual-mode sensor can correlate local pH for one DNA slice at one location-determined microbead, which can result in improved pH detection accuracy. Moreover, toward a high-throughput DNA sequencing, a correlated-double-sampling readout that supports large array for both modes is deployed to reduce pixel-to-pixel nonuniformity such as threshold voltage mismatch. The proposed CMOS dual-mode sensor is experimentally examined to show a well correlated pH map and optical image for microbeads with a pH sensitivity of 26.2 mV/pH, a fixed pattern noise (FPN) reduction from 4% to 0.3%, and a readout speed of 1200 frames/s. A dual-mode CMOS ISFET sensor with suppressed FPN for accurate large-arrayed pH sensing is proposed and demonstrated with state-of-the-art measured results toward accurate and high-throughput DNA sequencing. The developed dual-mode CMOS ISFET sensor has great potential for future personal genome diagnostics with high accuracy and low cost.

  6. Highly Accurate Tree Models Derived from Terrestrial Laser Scan Data: A Method Description

    Directory of Open Access Journals (Sweden)

    Jan Hackenberg

    2014-05-01

    Full Text Available This paper presents a method for fitting cylinders into a point cloud, derived from a terrestrial laser-scanned tree. Utilizing high scan quality data as the input, the resulting models describe the branching structure of the tree, capable of detecting branches with a diameter smaller than a centimeter. The cylinders are stored as a hierarchical tree-like data structure encapsulating parent-child neighbor relations and incorporating the tree’s direction of growth. This structure enables the efficient extraction of tree components, such as the stem or a single branch. The method was validated both by applying a comparison of the resulting cylinder models with ground truth data and by an analysis between the input point clouds and the models. Tree models were accomplished representing more than 99% of the input point cloud, with an average distance from the cylinder model to the point cloud within sub-millimeter accuracy. After validation, the method was applied to build two allometric models based on 24 tree point clouds as an example of the application. Computation terminated successfully within less than 30 min. For the model predicting the total above ground volume, the coefficient of determination was 0.965, showing the high potential of terrestrial laser-scanning for forest inventories.

  7. Bone position emission tomography with or without CT Is more accurate than bone scan for detection of bone metastasis

    International Nuclear Information System (INIS)

    Lee, Soo Jin; Lee, Wom Woo; Kim, Sang Eun

    2013-01-01

    Na1 8F bone positron emission tomography (bone PET) is a new imaging modality which is useful for the evaluation of bone diseases. Here, we compared the diagnostic accuracies between bone PET and bone scan for the detection of bone metastasis (BM). Sixteen cancer patients (M:F = 10:6, mean age = 60 ± 12 years) who underwent both bone PET and bone scan were analyzed. Bone PET was conducted 30 minutes after the injection of 370 MBq Na1 8F , and a bone scan was performed 3 hours after the injection of 1295 MBq 9 9mT c-hydroxymethylene diphosphonate. In the patient-based analysis (8 patients with BM and 8 without BM), the sensitivities of bone PET (100% 8/8) and bone scan (87.5% = 7/8) were not significantly different (p > 0.05), whereas the specificity of bone PET (87.5% = 7/8) was significantly greater than that of the bone scan (25% = 2/8) (p 8F bone PET is more accurate than bone scan for BM evaluation.

  8. Detecting atheromatous plaques in the aortic arch or supra-aortic arteries for more accurate stroke subtype classification.

    Science.gov (United States)

    Cui, Xiaoyang; Wu, Simiao; Zeng, Quantao; Xiao, Jiahe; Liu, Ming

    2015-02-01

    To investigate the correlations of atheromatous plaques in the aortic arch or supra-aortic arteries with intracranial arterial stenosis and carotid plaques in stroke patients, and to determine whether taking these plaques into account will reduce the proportion of patients in the undetermined etiology group. We prospectively enrolled 308 ischemic stroke patients, whose clinical characteristics and A-S-C-O classifications were compared with analyses of intracranial arteries, carotid arteries, aortic arch, and supra-aortic arteries. 125(40.6%) patients had plaques in the aortic arch or supra-aortic arteries, of which 106 (84.8%) had complex plaques. No correlations were observed between these plaques and carotid plaques ( p = 0.283) or intracranial arterial stenosis ( p = 0.097). After detecting the mobile thrombi in the aortic arch and supra-aortic arteries, the proportion of patients in the atherothrombosis group was increased from 33.8% to 55.5% ( p = 0.00), whereas the proportion of patients in stroke of undetermined etiology group was decreased from 19.2% to 11.0% ( p = 0.00). Examining only the carotid and intracranial arteries may not provide adequate information about large arteries in stroke patients. Therefore, it would be better to include a search for relevant plaques in the aortic arch or supra-aortic arteries in modern stroke workup, for it may lead to more accurate stroke subtype classification and guide secondary prevention.

  9. Quasi-closed phase forward-backward linear prediction analysis of speech for accurate formant detection and estimation.

    Science.gov (United States)

    Gowda, Dhananjaya; Airaksinen, Manu; Alku, Paavo

    2017-09-01

    Recently, a quasi-closed phase (QCP) analysis of speech signals for accurate glottal inverse filtering was proposed. However, the QCP analysis which belongs to the family of temporally weighted linear prediction (WLP) methods uses the conventional forward type of sample prediction. This may not be the best choice especially in computing WLP models with a hard-limiting weighting function. A sample selective minimization of the prediction error in WLP reduces the effective number of samples available within a given window frame. To counter this problem, a modified quasi-closed phase forward-backward (QCP-FB) analysis is proposed, wherein each sample is predicted based on its past as well as future samples thereby utilizing the available number of samples more effectively. Formant detection and estimation experiments on synthetic vowels generated using a physical modeling approach as well as natural speech utterances show that the proposed QCP-FB method yields statistically significant improvements over the conventional linear prediction and QCP methods.

  10. Accurate inference of shoot biomass from high-throughput images of cereal plants

    Directory of Open Access Journals (Sweden)

    Tester Mark

    2011-02-01

    Full Text Available Abstract With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model. For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent

  11. A Robust Motion Artifact Detection Algorithm for Accurate Detection of Heart Rates From Photoplethysmographic Signals Using Time-Frequency Spectral Features.

    Science.gov (United States)

    Dao, Duy; Salehizadeh, S M A; Noh, Yeonsik; Chong, Jo Woon; Cho, Chae Ho; McManus, Dave; Darling, Chad E; Mendelson, Yitzhak; Chon, Ki H

    2017-09-01

    Motion and noise artifacts (MNAs) impose limits on the usability of the photoplethysmogram (PPG), particularly in the context of ambulatory monitoring. MNAs can distort PPG, causing erroneous estimation of physiological parameters such as heart rate (HR) and arterial oxygen saturation (SpO2). In this study, we present a novel approach, "TifMA," based on using the time-frequency spectrum of PPG to first detect the MNA-corrupted data and next discard the nonusable part of the corrupted data. The term "nonusable" refers to segments of PPG data from which the HR signal cannot be recovered accurately. Two sequential classification procedures were included in the TifMA algorithm. The first classifier distinguishes between MNA-corrupted and MNA-free PPG data. Once a segment of data is deemed MNA-corrupted, the next classifier determines whether the HR can be recovered from the corrupted segment or not. A support vector machine (SVM) classifier was used to build a decision boundary for the first classification task using data segments from a training dataset. Features from time-frequency spectra of PPG were extracted to build the detection model. Five datasets were considered for evaluating TifMA performance: (1) and (2) were laboratory-controlled PPG recordings from forehead and finger pulse oximeter sensors with subjects making random movements, (3) and (4) were actual patient PPG recordings from UMass Memorial Medical Center with random free movements and (5) was a laboratory-controlled PPG recording dataset measured at the forehead while the subjects ran on a treadmill. The first dataset was used to analyze the noise sensitivity of the algorithm. Datasets 2-4 were used to evaluate the MNA detection phase of the algorithm. The results from the first phase of the algorithm (MNA detection) were compared to results from three existing MNA detection algorithms: the Hjorth, kurtosis-Shannon entropy, and time-domain variability-SVM approaches. This last is an approach

  12. A highly accurate algorithm for the solution of the point kinetics equations

    International Nuclear Information System (INIS)

    Ganapol, B.D.

    2013-01-01

    Highlights: • Point kinetics equations for nuclear reactor transient analysis are numerically solved to extreme accuracy. • Results for classic benchmarks found in the literature are given to 9-digit accuracy. • Recent results of claimed accuracy are shown to be less accurate than claimed. • Arguably brings a chapter of numerical evaluation of the PKEs to a close. - Abstract: Attempts to resolve the point kinetics equations (PKEs) describing nuclear reactor transients have been the subject of numerous articles and texts over the past 50 years. Some very innovative methods, such as the RTS (Reactor Transient Simulation) and CAC (Continuous Analytical Continuation) methods of G.R. Keepin and J. Vigil respectively, have been shown to be exceptionally useful. Recently however, several authors have developed methods they consider accurate without a clear basis for their assertion. In response, this presentation will establish a definitive set of benchmarks to enable those developing PKE methods to truthfully assess the degree of accuracy of their methods. Then, with these benchmarks, two recently published methods, found in this journal will be shown to be less accurate than claimed and a legacy method from 1984 will be confirmed

  13. A highly accurate positioning and orientation system based on the usage of four-cluster fibre optic gyros

    International Nuclear Information System (INIS)

    Zhang, Xiaoyue; Lin, Zhili; Zhang, Chunxi

    2013-01-01

    A highly accurate positioning and orientation technique based on four-cluster fibre optic gyros (FOGs) is presented. The four-cluster FOG inertial measurement unit (IMU) comprises three low-precision FOGs, one static high-precision FOG and three accelerometers. To realize high-precision positioning and orientation, the static alignment (north-seeking) before vehicle manoeuvre was divided into a low-precision self-alignment phase and a high-precision north-seeking (online calibration) phase. The high-precision FOG measurement information was introduced to obtain high-precision azimuth alignment (north-seeking) result and achieve online calibration of the low-precision three-cluster FOG. The results of semi-physical simulation were presented to validate the availability and utility of the highly accurate positioning and orientation technique based on the four-cluster FOGs. (paper)

  14. Compression ultrasonography of the lower extremity with portable vascular ultrasonography can accurately detect deep venous thrombosis in the emergency department.

    Science.gov (United States)

    Crisp, Jonathan G; Lovato, Luis M; Jang, Timothy B

    2010-12-01

    Compression ultrasonography of the lower extremity is an established method of detecting proximal lower extremity deep venous thrombosis when performed by a certified operator in a vascular laboratory. Our objective is to determine the sensitivity and specificity of bedside 2-point compression ultrasonography performed in the emergency department (ED) with portable vascular ultrasonography for the detection of proximal lower extremity deep venous thrombosis. We did this by directly comparing emergency physician-performed ultrasonography to lower extremity duplex ultrasonography performed by the Department of Radiology. This was a prospective, cross-sectional study and diagnostic test assessment of a convenience sample of ED patients with a suspected lower extremity deep venous thrombosis, conducted at a single-center, urban, academic ED. All physicians had a 10-minute training session before enrolling patients. ED compression ultrasonography occurred before Department of Radiology ultrasonography and involved identification of 2 specific points: the common femoral and popliteal vessels, with subsequent compression of the common femoral and popliteal veins. The study result was considered positive for proximal lower extremity deep venous thrombosis if either vein was incompressible or a thrombus was visualized. Sensitivity and specificity were calculated with the final radiologist interpretation of the Department of Radiology ultrasonography as the criterion standard. A total of 47 physicians performed 199 2-point compression ultrasonographic examinations in the ED. Median number of examinations per physician was 2 (range 1 to 29 examinations; interquartile range 1 to 5 examinations). There were 45 proximal lower extremity deep venous thromboses observed on Department of Radiology evaluation, all correctly identified by ED 2-point compression ultrasonography. The 153 patients without proximal lower extremity deep venous thrombosis all had a negative ED compression

  15. An N-targeting real-time PCR strategy for the accurate detection of spring viremia of carp virus.

    Science.gov (United States)

    Shao, Ling; Xiao, Yu; He, Zhengkan; Gao, Longying

    2016-03-01

    Spring viremia of carp virus (SVCV) is a highly pathogenic agent of several economically important Cyprinidae fish species. Currently, there are no effective vaccines or drugs for this virus, and prevention of the disease mostly relies on prompt diagnosis. Previously, nested RT-PCR and RT-qPCR detection methods based on the glycoprotein gene G have been developed. However, the high genetic diversity of the G gene seriously limits the reliability of those methods. Compared with the G gene, phylogenetic analyses indicate that the nucleoprotein gene N is more conserved. Furthermore, studies in other members of the Rhabdoviridae family reveals that their gene transcription level follows the order N>P>M>G>L, indicating that an N gene based RT-PCR should have higher sensitivity. Therefore, two pairs of primers and two corresponding probes targeting the conserved regions of the N gene were designed. RT-qPCR assays demonstrated all primers and probes could detect phylogenetically distant isolates specifically and efficiently. Moreover, in artificially infected fish, the detected copy numbers of the N gene were much higher than those of the G gene in all tissues, and both the N and G gene copy numbers were highest in the kidney and spleen. Testing in 1100 farm-raised fish also showed that the N-targeting strategy was more reliable than the G-targeting methods. The method developed in this study provides a reliable tool for the rapid diagnosis of SVCV. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Pairagon: a highly accurate, HMM-based cDNA-to-genome aligner

    DEFF Research Database (Denmark)

    Lu, David V; Brown, Randall H; Arumugam, Manimozhiyan

    2009-01-01

    MOTIVATION: The most accurate way to determine the intron-exon structures in a genome is to align spliced cDNA sequences to the genome. Thus, cDNA-to-genome alignment programs are a key component of most annotation pipelines. The scoring system used to choose the best alignment is a primary...... determinant of alignment accuracy, while heuristics that prevent consideration of certain alignments are a primary determinant of runtime and memory usage. Both accuracy and speed are important considerations in choosing an alignment algorithm, but scoring systems have received much less attention than...

  17. Accurate modeling of high frequency microelectromechanical systems (MEMS switches in time- and frequency-domainc

    Directory of Open Access Journals (Sweden)

    F. Coccetti

    2003-01-01

    Full Text Available In this contribution we present an accurate investigation of three different techniques for the modeling of complex planar circuits. The em analysis is performed by means of different electromagnetic full-wave solvers in the timedomain and in the frequency-domain. The first one is the Transmission Line Matrix (TLM method. In the second one the TLM method is combined with the Integral Equation (IE method. The latter is based on the Generalized Transverse Resonance Diffraction (GTRD. In order to test the methods we model different structures and compare the calculated Sparameters to measured results, with good agreement.

  18. Highly Accurate Derivatives for LCL-Filtered Grid Converter with Capacitor Voltage Active Damping

    DEFF Research Database (Denmark)

    Xin, Zhen; Loh, Poh Chiang; Wang, Xiongfei

    2016-01-01

    The middle capacitor voltage of an LCL-filter, if fed back for synchronization, can be used for active damping. An extra sensor for measuring the capacitor current is then avoided. Relating the capacitor voltage to existing popular damping techniques designed with capacitor current feedback would...... are then proposed, based on either second-order or non-ideal generalized integrator. Performances of these derivatives have been found to match the ideal “s” function closely. Active damping based on capacitor voltage feedback can therefore be realized accurately. Experimental results presented have verified...

  19. Highly accurate potential calculations for cylindrically symmetric geometries using multi-region FDM: A review

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, David, E-mail: dej@kingcon.com [IJL Research Center, Newark, VT 05871 (United States)

    2011-07-21

    This paper is a review of multi-region FDM, a numerical technique for accurately determining electrostatic potentials in cylindrically symmetric geometries. Multi-region FDM can be thought of as the union of various individual elements: a single region FDM process: a method for algorithmic development; a method for auto creating a multi-region structure; the process for the relaxation of multi-region structures. Each element will be briefly described along with its integration into the multi-region relaxation process itself.

  20. The determination of the pressure-viscosity coefficient of a lubricant through an accurate film thickness formula and accurate film thickness measurements : part 2 : high L values

    NARCIS (Netherlands)

    Leeuwen, van H.J.

    2011-01-01

    The pressure-viscosity coefficient of a traction fluid is determined by fitting calculation results on accurate film thickness measurements, obtained at different speeds, loads, and temperatures. Through experiments, covering a range of 5.6

  1. High Concentrations of Measles Neutralizing Antibodies and High-Avidity Measles IgG Accurately Identify Measles Reinfection Cases

    Science.gov (United States)

    Rota, Jennifer S.; Hickman, Carole J.; Mercader, Sara; Redd, Susan; McNall, Rebecca J.; Williams, Nobia; McGrew, Marcia; Walls, M. Laura; Rota, Paul A.; Bellini, William J.

    2016-01-01

    In the United States, approximately 9% of the measles cases reported from 2012 to 2014 occurred in vaccinated individuals. Laboratory confirmation of measles in vaccinated individuals is challenging since IgM assays can give inconclusive results. Although a positive reverse transcription (RT)-PCR assay result from an appropriately timed specimen can provide confirmation, negative results may not rule out a highly suspicious case. Detection of high-avidity measles IgG in serum samples provides laboratory evidence of a past immunologic response to measles from natural infection or immunization. High concentrations of measles neutralizing antibody have been observed by plaque reduction neutralization (PRN) assays among confirmed measles cases with high-avidity IgG, referred to here as reinfection cases (RICs). In this study, we evaluated the utility of measuring levels of measles neutralizing antibody to distinguish RICs from noncases by receiver operating characteristic curve analysis. Single and paired serum samples with high-avidity measles IgG from suspected measles cases submitted to the CDC for routine surveillance were used for the analysis. The RICs were confirmed by a 4-fold rise in PRN titer or by RT-quantitative PCR (RT-qPCR) assay, while the noncases were negative by both assays. Discrimination accuracy was high with serum samples collected ≥3 days after rash onset (area under the curve, 0.953; 95% confidence interval [CI], 0.854 to 0.993). Measles neutralizing antibody concentrations of ≥40,000 mIU/ml identified RICs with 90% sensitivity (95% CI, 74 to 98%) and 100% specificity (95% CI, 82 to 100%). Therefore, when serological or RT-qPCR results are unavailable or inconclusive, suspected measles cases with high-avidity measles IgG can be confirmed as RICs by measles neutralizing antibody concentrations of ≥40,000 mIU/ml. PMID:27335386

  2. Toward optimizing patient-specific IMRT QA techniques in the accurate detection of dosimetrically acceptable and unacceptable patient plans.

    Science.gov (United States)

    McKenzie, Elizabeth M; Balter, Peter A; Stingo, Francesco C; Jones, Jimmy; Followill, David S; Kry, Stephen F

    2014-12-01

    in the performance of any device between gamma criteria of 2%/2 mm, 3%/3 mm, and 5%/3 mm. Finally, optimal cutoffs (e.g., percent of pixels passing gamma) were determined for each device and while clinical practice commonly uses a threshold of 90% of pixels passing for most cases, these results showed variability in the optimal cutoff among devices. IMRT QA devices have differences in their ability to accurately detect dosimetrically acceptable and unacceptable plans. Field-by-field analysis with a MapCheck device and use of the MapCheck with a MapPhan phantom while delivering at planned rotational gantry angles resulted in a significantly poorer ability to accurately sort acceptable and unacceptable plans compared with the other techniques examined. Patient-specific IMRT QA techniques in general should be thoroughly evaluated for their ability to correctly differentiate acceptable and unacceptable plans. Additionally, optimal agreement thresholds should be identified and used as common clinical thresholds typically worked very poorly to identify unacceptable plans.

  3. Distinguishing highly confident accurate and inaccurate memory: insights about relevant and irrelevant influences on memory confidence.

    Science.gov (United States)

    Chua, Elizabeth F; Hannula, Deborah E; Ranganath, Charan

    2012-01-01

    It is generally believed that accuracy and confidence in one's memory are related, but there are many instances when they diverge. Accordingly it is important to disentangle the factors that contribute to memory accuracy and confidence, especially those factors that contribute to confidence, but not accuracy. We used eye movements to separately measure fluent cue processing, the target recognition experience, and relative evidence assessment on recognition confidence and accuracy. Eye movements were monitored during a face-scene associative recognition task, in which participants first saw a scene cue, followed by a forced-choice recognition test for the associated face, with confidence ratings. Eye movement indices of the target recognition experience were largely indicative of accuracy, and showed a relationship to confidence for accurate decisions. In contrast, eye movements during the scene cue raised the possibility that more fluent cue processing was related to higher confidence for both accurate and inaccurate recognition decisions. In a second experiment we manipulated cue familiarity, and therefore cue fluency. Participants showed higher confidence for cue-target associations for when the cue was more familiar, especially for incorrect responses. These results suggest that over-reliance on cue familiarity and under-reliance on the target recognition experience may lead to erroneous confidence.

  4. Full automatic fiducial marker detection on coil arrays for accurate instrumentation placement during MRI guided breast interventions

    Science.gov (United States)

    Filippatos, Konstantinos; Boehler, Tobias; Geisler, Benjamin; Zachmann, Harald; Twellmann, Thorsten

    2010-02-01

    With its high sensitivity, dynamic contrast-enhanced MR imaging (DCE-MRI) of the breast is today one of the first-line tools for early detection and diagnosis of breast cancer, particularly in the dense breast of young women. However, many relevant findings are very small or occult on targeted ultrasound images or mammography, so that MRI guided biopsy is the only option for a precise histological work-up [1]. State-of-the-art software tools for computer-aided diagnosis of breast cancer in DCE-MRI data offer also means for image-based planning of biopsy interventions. One step in the MRI guided biopsy workflow is the alignment of the patient position with the preoperative MR images. In these images, the location and orientation of the coil localization unit can be inferred from a number of fiducial markers, which for this purpose have to be manually or semi-automatically detected by the user. In this study, we propose a method for precise, full-automatic localization of fiducial markers, on which basis a virtual localization unit can be subsequently placed in the image volume for the purpose of determining the parameters for needle navigation. The method is based on adaptive thresholding for separating breast tissue from background followed by rigid registration of marker templates. In an evaluation of 25 clinical cases comprising 4 different commercial coil array models and 3 different MR imaging protocols, the method yielded a sensitivity of 0.96 at a false positive rate of 0.44 markers per case. The mean distance deviation between detected fiducial centers and ground truth information that was appointed from a radiologist was 0.94mm.

  5. Energy-switching potential energy surface for the water molecule revisited: A highly accurate singled-sheeted form.

    Science.gov (United States)

    Galvão, B R L; Rodrigues, S P J; Varandas, A J C

    2008-07-28

    A global ab initio potential energy surface is proposed for the water molecule by energy-switching/merging a highly accurate isotope-dependent local potential function reported by Polyansky et al. [Science 299, 539 (2003)] with a global form of the many-body expansion type suitably adapted to account explicitly for the dynamical correlation and parametrized from extensive accurate multireference configuration interaction energies extrapolated to the complete basis set limit. The new function mimics also the complicated Sigma/Pi crossing that arises at linear geometries of the water molecule.

  6. A Highly Accurate and Efficient Analytical Approach to Bridge Deck Free Vibration Analysis

    Directory of Open Access Journals (Sweden)

    D.J. Gorman

    2000-01-01

    Full Text Available The superposition method is employed to obtain an accurate analytical type solution for the free vibration frequencies and mode shapes of multi-span bridge decks. Free edge conditions are imposed on the long edges running in the direction of the deck. Inter-span support is of the simple (knife-edge type. The analysis is valid regardless of the number of spans or their individual lengths. Exact agreement is found when computed results are compared with known eigenvalues for bridge decks with all spans of equal length. Mode shapes and eigenvalues are presented for typical bridge decks of three and four span lengths. In each case torsional and non-torsional modes are studied.

  7. Nucleobase-functionalized grapheme nanoribbons for accurate high-speed DNA sequencing

    NARCIS (Netherlands)

    Paulechka, Eugene; Wassenaar, Tsjerk; Kroenlein, Kenneth; Kazakov, Andrei; Smolyanitsky, Alex

    2016-01-01

    We propose a water-immersed nucleobase-functionalized suspended graphene nanoribbon as an intrinsically selective device for nucleotide detection. The proposed sensing method combines Watson–Crick selective base pairing with graphene's capacity for converting anisotropic lattice strain to changes in

  8. Sentinel lymph node procedure is highly accurate in squamous cell carcinoma of the vulva

    NARCIS (Netherlands)

    de Hullu, JA; Hollema, H; Piers, DA; Verheijen, RHM; van Diest, PJ; Mourits, MJE; Aalders, JG; van der Zee, AGJ

    Purpose: To determine the diagnostic accuracy of the sentinel lymph node procedure in patients with squamous cell carcinoma of the vulva and to investigate whether step sectioning and immunohistochemistry of sentinel lymph nodes increase the sensitivity for detection of metastases. Patients and

  9. High performance liquid chromatography method for rapid and accurate determination of homocysteine in plasma and serum

    DEFF Research Database (Denmark)

    Vester, Birte; Rasmussen, K

    1991-01-01

    with ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate, and HPLC separation followed by fluorescence detection. The linearity of the assays is established and the coefficient of variation is 3.0%. Stability studies show that blood samples must be cooled or centrifuged immediately after venipuncture...

  10. Adenosine stress cardiovascular magnetic resonance with variable-density spiral pulse sequences accurately detects coronary artery disease: initial clinical evaluation.

    Science.gov (United States)

    Salerno, Michael; Taylor, Angela; Yang, Yang; Kuruvilla, Sujith; Ragosta, Michael; Meyer, Craig H; Kramer, Christopher M

    2014-07-01

    Adenosine stress cardiovascular magnetic resonance perfusion imaging can be limited by motion-induced dark-rim artifacts, which may be mistaken for true perfusion abnormalities. A high-resolution variable-density spiral pulse sequence with a novel density compensation strategy has been shown to reduce dark-rim artifacts in first-pass perfusion imaging. We aimed to assess the clinical performance of adenosine stress cardiovascular magnetic resonance using this new perfusion sequence to detect obstructive coronary artery disease. Cardiovascular magnetic resonance perfusion imaging was performed during adenosine stress (140 μg/kg per minute) and at rest on a Siemens 1.5-T Avanto scanner in 41 subjects with chest pain scheduled for coronary angiography. Perfusion images were acquired during injection of 0.1 mmol/kg Gadolinium-diethylenetriaminepentacetate at 3 short-axis locations using a saturation recovery interleaved variable-density spiral pulse sequence. Significant stenosis was defined as >50% by quantitative coronary angiography. Two blinded reviewers evaluated the perfusion images for the presence of adenosine-induced perfusion abnormalities and assessed image quality using a 5-point scale (1 [poor] to 5 [excellent]). The prevalence of obstructive coronary artery disease by quantitative coronary angiography was 68%. The average sensitivity, specificity, and accuracy were 89%, 85%, and 88%, respectively, with a positive predictive value and negative predictive value of 93% and 79%, respectively. The average image quality score was 4.4±0.7, with only 1 study with more than mild dark-rim artifacts. There was good inter-reader reliability with a κ statistic of 0.67. Spiral adenosine stress cardiovascular magnetic resonance results in high diagnostic accuracy for the detection of obstructive coronary artery disease with excellent image quality and minimal dark-rim artifacts. © 2014 American Heart Association, Inc.

  11. Accurate Angle Estimator for High-Frame-rate 2-D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Stuart, Matthias Bo; Lindskov Hansen, Kristoffer

    2016-01-01

    This paper presents a novel approach for estimating 2-D flow angles using a high-frame-rate ultrasound method. The angle estimator features high accuracy and low standard deviation (SD) over the full 360° range. The method is validated on Field II simulations and phantom measurements using...

  12. Highly accurate prediction of food challenge outcome using routinely available clinical data.

    Science.gov (United States)

    DunnGalvin, Audrey; Daly, Deirdre; Cullinane, Claire; Stenke, Emily; Keeton, Diane; Erlewyn-Lajeunesse, Mich; Roberts, Graham C; Lucas, Jane; Hourihane, Jonathan O'B

    2011-03-01

    Serum specific IgE or skin prick tests are less useful at levels below accepted decision points. We sought to develop and validate a model to predict food challenge outcome by using routinely collected data in a diverse sample of children considered suitable for food challenge. The proto-algorithm was generated by using a limited data set from 1 service (phase 1). We retrospectively applied, evaluated, and modified the initial model by using an extended data set in another center (phase 2). Finally, we prospectively validated the model in a blind study in a further group of children undergoing food challenge for peanut, milk, or egg in the second center (phase 3). Allergen-specific models were developed for peanut, egg, and milk. Phase 1 (N = 429) identified 5 clinical factors associated with diagnosis of food allergy by food challenge. In phase 2 (N = 289), we examined the predictive ability of 6 clinical factors: skin prick test, serum specific IgE, total IgE minus serum specific IgE, symptoms, sex, and age. In phase 3 (N = 70), 97% of cases were accurately predicted as positive and 94% as negative. Our model showed an advantage in clinical prediction compared with serum specific IgE only, skin prick test only, and serum specific IgE and skin prick test (92% accuracy vs 57%, and 81%, respectively). Our findings have implications for the improved delivery of food allergy-related health care, enhanced food allergy-related quality of life, and economized use of health service resources by decreasing the number of food challenges performed. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  13. An accurate energy-range relationship for high-energy electron beams in arbitrary materials

    International Nuclear Information System (INIS)

    Sorcini, B.B.; Brahme, A.

    1994-01-01

    A general analytical energy-range relationship has been derived to relate the practical range, R p to the most probable energy, E p , of incident electron beams in the range 1 to 50 MeV and above, for absorbers of any atomic number. In the present study only Monte Carlo data determined with the new ITS.3 code have been employed. The standard deviations of the mean deviation from the Monte Carlo data at any energy are about 0.10, 0.12, 0.04, 0.11, 0.04, 0.03, 0.02 mm for Be, C, H 2 O, Al, Cu, Ag and U, respectively, and the relative standard deviation of the mean is about 0.5% for all materials. The fitting program gives some priority to water-equivalent materials, which explains the low standard deviation for water. A small error in the fall-off slope can give a different value for R p . We describe a new method which reduces the uncertainty in the R p determination, by fitting an odd function to the descending portion of the depth-dose curve in order to accurately determine the tangent at the inflection point, and thereby the practical range. An approximate inverse relation is given expressing the most probable energy of an electron beam as a function of the practical range. The resultant relative standard error of the energy is less than 0.7%, and the maximum energy error ΔE p is less than 0.3 MeV. (author)

  14. Accurate on-chip measurement of the Seebeck coefficient of high mobility small molecule organic semiconductors

    Science.gov (United States)

    Warwick, C. N.; Venkateshvaran, D.; Sirringhaus, H.

    2015-09-01

    We present measurements of the Seebeck coefficient in two high mobility organic small molecules, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) and 2,9-didecyl-dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10-DNTT). The measurements are performed in a field effect transistor structure with high field effect mobilities of approximately 3 cm2/V s. This allows us to observe both the charge concentration and temperature dependence of the Seebeck coefficient. We find a strong logarithmic dependence upon charge concentration and a temperature dependence within the measurement uncertainty. Despite performing the measurements on highly polycrystalline evaporated films, we see an agreement in the Seebeck coefficient with modelled values from Shi et al. [Chem. Mater. 26, 2669 (2014)] at high charge concentrations. We attribute deviations from the model at lower charge concentrations to charge trapping.

  15. Accurate on-chip measurement of the Seebeck coefficient of high mobility small molecule organic semiconductors

    Directory of Open Access Journals (Sweden)

    C. N. Warwick

    2015-09-01

    Full Text Available We present measurements of the Seebeck coefficient in two high mobility organic small molecules, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT and 2,9-didecyl-dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT. The measurements are performed in a field effect transistor structure with high field effect mobilities of approximately 3 cm2/V s. This allows us to observe both the charge concentration and temperature dependence of the Seebeck coefficient. We find a strong logarithmic dependence upon charge concentration and a temperature dependence within the measurement uncertainty. Despite performing the measurements on highly polycrystalline evaporated films, we see an agreement in the Seebeck coefficient with modelled values from Shi et al. [Chem. Mater. 26, 2669 (2014] at high charge concentrations. We attribute deviations from the model at lower charge concentrations to charge trapping.

  16. Efficient and accurate nearest neighbor and closest pair search in high-dimensional space

    KAUST Repository

    Tao, Yufei; Yi, Ke; Sheng, Cheng; Kalnis, Panos

    2010-01-01

    Nearest Neighbor (NN) search in high-dimensional space is an important problem in many applications. From the database perspective, a good solution needs to have two properties: (i) it can be easily incorporated in a relational database, and (ii

  17. A highly accurate finite-difference method with minimum dispersion error for solving the Helmholtz equation

    KAUST Repository

    Wu, Zedong; Alkhalifah, Tariq Ali

    2018-01-01

    Numerical simulation of the acoustic wave equation in either isotropic or anisotropic media is crucial to seismic modeling, imaging and inversion. Actually, it represents the core computation cost of these highly advanced seismic processing methods

  18. Identification of a 251 gene expression signature that can accurately detect M. tuberculosis in patients with and without HIV co-infection.

    Directory of Open Access Journals (Sweden)

    Noor Dawany

    Full Text Available BACKGROUND: Co-infection with tuberculosis (TB is the leading cause of death in HIV-infected individuals. However, diagnosis of TB, especially in the presence of an HIV co-infection, can be limiting due to the high inaccuracy associated with the use of conventional diagnostic methods. Here we report a gene signature that can identify a tuberculosis infection in patients co-infected with HIV as well as in the absence of HIV. METHODS: We analyzed global gene expression data from peripheral blood mononuclear cell (PBMC samples of patients that were either mono-infected with HIV or co-infected with HIV/TB and used support vector machines to identify a gene signature that can distinguish between the two classes. We then validated our results using publically available gene expression data from patients mono-infected with TB. RESULTS: Our analysis successfully identified a 251-gene signature that accurately distinguishes patients co-infected with HIV/TB from those infected with HIV only, with an overall accuracy of 81.4% (sensitivity = 76.2%, specificity = 86.4%. Furthermore, we show that our 251-gene signature can also accurately distinguish patients with active TB in the absence of an HIV infection from both patients with a latent TB infection and healthy controls (88.9-94.7% accuracy; 69.2-90% sensitivity and 90.3-100% specificity. We also demonstrate that the expression levels of the 251-gene signature diminish as a correlate of the length of TB treatment. CONCLUSIONS: A 251-gene signature is described to (a detect TB in the presence or absence of an HIV co-infection, and (b assess response to treatment following anti-TB therapy.

  19. High-Resolution Photoionization, Photoelectron and Photodissociation Studies. Determination of Accurate Energetic and Spectroscopic Database for Combustion Radicals and Molecules

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Cheuk-Yiu [Univ. of California, Davis, CA (United States)

    2016-04-25

    The main goal of this research program was to obtain accurate thermochemical and spectroscopic data, such as ionization energies (IEs), 0 K bond dissociation energies, 0 K heats of formation, and spectroscopic constants for radicals and molecules and their ions of relevance to combustion chemistry. Two unique, generally applicable vacuum ultraviolet (VUV) laser photoion-photoelectron apparatuses have been developed in our group, which have used for high-resolution photoionization, photoelectron, and photodissociation studies for many small molecules of combustion relevance.

  20. High Detectivity Graphene-Silicon Heterojunction Photodetector.

    Science.gov (United States)

    Li, Xinming; Zhu, Miao; Du, Mingde; Lv, Zheng; Zhang, Li; Li, Yuanchang; Yang, Yao; Yang, Tingting; Li, Xiao; Wang, Kunlin; Zhu, Hongwei; Fang, Ying

    2016-02-03

    A graphene/n-type silicon (n-Si) heterojunction has been demonstrated to exhibit strong rectifying behavior and high photoresponsivity, which can be utilized for the development of high-performance photodetectors. However, graphene/n-Si heterojunction photodetectors reported previously suffer from relatively low specific detectivity due to large dark current. Here, by introducing a thin interfacial oxide layer, the dark current of graphene/n-Si heterojunction has been reduced by two orders of magnitude at zero bias. At room temperature, the graphene/n-Si photodetector with interfacial oxide exhibits a specific detectivity up to 5.77 × 10(13) cm Hz(1/2) W(-1) at the peak wavelength of 890 nm in vacuum, which is highest reported detectivity at room temperature for planar graphene/Si heterojunction photodetectors. In addition, the improved graphene/n-Si heterojunction photodetectors possess high responsivity of 0.73 A W(-1) and high photo-to-dark current ratio of ≈10(7) . The current noise spectral density of the graphene/n-Si photodetector has been characterized under ambient and vacuum conditions, which shows that the dark current can be further suppressed in vacuum. These results demonstrate that graphene/Si heterojunction with interfacial oxide is promising for the development of high detectivity photodetectors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Accurate, high-throughput typing of copy number variation using paralogue ratios from dispersed repeats.

    NARCIS (Netherlands)

    Armour, J.A.; Palla, R.; Zeeuwen, P.L.J.M.; Heijer, M. den; Schalkwijk, J.; Hollox, E.J.

    2007-01-01

    Recent work has demonstrated an unexpected prevalence of copy number variation in the human genome, and has highlighted the part this variation may play in predisposition to common phenotypes. Some important genes vary in number over a high range (e.g. DEFB4, which commonly varies between two and

  2. High-throughput automated microfluidic sample preparation for accurate microbial genomics.

    Science.gov (United States)

    Kim, Soohong; De Jonghe, Joachim; Kulesa, Anthony B; Feldman, David; Vatanen, Tommi; Bhattacharyya, Roby P; Berdy, Brittany; Gomez, James; Nolan, Jill; Epstein, Slava; Blainey, Paul C

    2017-01-27

    Low-cost shotgun DNA sequencing is transforming the microbial sciences. Sequencing instruments are so effective that sample preparation is now the key limiting factor. Here, we introduce a microfluidic sample preparation platform that integrates the key steps in cells to sequence library sample preparation for up to 96 samples and reduces DNA input requirements 100-fold while maintaining or improving data quality. The general-purpose microarchitecture we demonstrate supports workflows with arbitrary numbers of reaction and clean-up or capture steps. By reducing the sample quantity requirements, we enabled low-input (∼10,000 cells) whole-genome shotgun (WGS) sequencing of Mycobacterium tuberculosis and soil micro-colonies with superior results. We also leveraged the enhanced throughput to sequence ∼400 clinical Pseudomonas aeruginosa libraries and demonstrate excellent single-nucleotide polymorphism detection performance that explained phenotypically observed antibiotic resistance. Fully-integrated lab-on-chip sample preparation overcomes technical barriers to enable broader deployment of genomics across many basic research and translational applications.

  3. Limited Angle Torque Motors Having High Torque Density, Used in Accurate Drive Systems

    Directory of Open Access Journals (Sweden)

    R. Obreja

    2011-01-01

    Full Text Available A torque motor is a special electric motor that is able to develop the highest possible torque in a certain volume. A torque motor usually has a pancake configuration, and is directly jointed to a drive system (without a gear box. A limited angle torque motor is a torque motor that has no rotary electromagnetic field — in certain papers it is referred to as a linear electromagnet. The main intention of the authors for this paper is to present a means for analyzing and designing a limited angle torque motor only through the finite element method. Users nowadays require very high-performance limited angle torque motors with high density torque. It is therefore necessary to develop the highest possible torque in a relatively small volume. A way to design such motors is by using numerical methods based on the finite element method.

  4. Development and operation of a high-throughput accurate-wavelength lens-based spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Ronald E., E-mail: rbell@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15

    A high-throughput spectrometer for the 400–820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm{sup −1} grating is matched with fast f/1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy ≤0.075 arc sec. A high quantum efficiency low-etaloning CCD detector allows operation at longer wavelengths. A patch panel allows input fibers to interface with interchangeable fiber holders that attach to a kinematic mount at the entrance slit. Computer-controlled hardware allows automated control of wavelength, timing, f-number, automated data collection, and wavelength calibration.

  5. An experimental device for accurate ultrasounds measurements in liquid foods at high pressure

    International Nuclear Information System (INIS)

    Hidalgo-Baltasar, E; Taravillo, M; Baonza, V G; Sanz, P D; Guignon, B

    2012-01-01

    The use of high hydrostatic pressure to ensure safe and high-quality product has markedly increased in the food industry during the last decade. Ultrasonic sensors can be employed to control such processes in an equivalent way as they are currently used in processes carried out at room pressure. However, their installation, calibration and use are particularly challenging in the context of a high pressure environment. Besides, data about acoustic properties of food under pressure and even for water are quite scarce in the pressure range of interest for food treatment (namely, above 200 MPa). The objective of this work was to establish a methodology to determine the speed of sound in foods under pressure. An ultrasonic sensor using the multiple reflections method was adapted to a lab-scale HHP equipment to determine the speed of sound in water between 253.15 and 348.15 K, and at pressures up to 700 MPa. The experimental speed-of-sound data were compared to the data calculated from the equation of state of water (IAPWS-95 formulation). From this analysis, the way to calibrate cell path was validated. After this calibration procedure, the speed of sound could be determined in liquid foods by using this sensor with a relative uncertainty between (0.22 and 0.32) % at a confidence level of 95 % over the whole pressure domain.

  6. SINA: accurate high-throughput multiple sequence alignment of ribosomal RNA genes.

    Science.gov (United States)

    Pruesse, Elmar; Peplies, Jörg; Glöckner, Frank Oliver

    2012-07-15

    In the analysis of homologous sequences, computation of multiple sequence alignments (MSAs) has become a bottleneck. This is especially troublesome for marker genes like the ribosomal RNA (rRNA) where already millions of sequences are publicly available and individual studies can easily produce hundreds of thousands of new sequences. Methods have been developed to cope with such numbers, but further improvements are needed to meet accuracy requirements. In this study, we present the SILVA Incremental Aligner (SINA) used to align the rRNA gene databases provided by the SILVA ribosomal RNA project. SINA uses a combination of k-mer searching and partial order alignment (POA) to maintain very high alignment accuracy while satisfying high throughput performance demands. SINA was evaluated in comparison with the commonly used high throughput MSA programs PyNAST and mothur. The three BRAliBase III benchmark MSAs could be reproduced with 99.3, 97.6 and 96.1 accuracy. A larger benchmark MSA comprising 38 772 sequences could be reproduced with 98.9 and 99.3% accuracy using reference MSAs comprising 1000 and 5000 sequences. SINA was able to achieve higher accuracy than PyNAST and mothur in all performed benchmarks. Alignment of up to 500 sequences using the latest SILVA SSU/LSU Ref datasets as reference MSA is offered at http://www.arb-silva.de/aligner. This page also links to Linux binaries, user manual and tutorial. SINA is made available under a personal use license.

  7. Micro-UFO (Untethered Floating Object: A Highly Accurate Microrobot Manipulation Technique

    Directory of Open Access Journals (Sweden)

    Hüseyin Uvet

    2018-03-01

    Full Text Available A new microrobot manipulation technique with high precision (nano level positional accuracy to move in a liquid environment with diamagnetic levitation is presented. Untethered manipulation of microrobots by means of externally applied magnetic forces has been emerging as a promising field of research, particularly due to its potential for medical and biological applications. The purpose of the presented method is to eliminate friction force between the surface of the substrate and microrobot. In an effort to achieve high accuracy motion, required magnetic force for the levitation of the microrobot was determined by finite element method (FEM simulations in COMSOL (version 5.3, COMSOL Inc., Stockholm, Sweden and verified by experimental results. According to position of the lifter magnet, the levitation height of the microrobot in the liquid was found analytically, and compared with the experimental results head-to-head. The stable working range of the microrobot is between 30 µm to 330 µm, and it was confirmed in both simulations and experimental results. It can follow the given trajectory with high accuracy (<1 µm error avg. at varied speeds and levitation heights. Due to the nano-level positioning accuracy, desired locomotion can be achieved in pre-specified trajectories (sinusoidal or circular. During its locomotion, phase difference between lifter magnet and carrier magnet has been observed, and relation with drag force effect has been discussed. Without using strong electromagnets or bulky permanent magnets, our manipulation approach can move the microrobot in three dimensions in a liquid environment.

  8. Study on high power ultraviolet laser oil detection system

    Science.gov (United States)

    Jin, Qi; Cui, Zihao; Bi, Zongjie; Zhang, Yanchao; Tian, Zhaoshuo; Fu, Shiyou

    2018-03-01

    Laser Induce Fluorescence (LIF) is a widely used new telemetry technology. It obtains information about oil spill and oil film thickness by analyzing the characteristics of stimulated fluorescence and has an important application in the field of rapid analysis of water composition. A set of LIF detection system for marine oil pollution is designed in this paper, which uses 355nm high-energy pulsed laser as the excitation light source. A high-sensitivity image intensifier is used in the detector. The upper machine sends a digital signal through a serial port to achieve nanoseconds range-gated width control for image intensifier. The target fluorescence spectrum image is displayed on the image intensifier by adjusting the delay time and the width of the pulse signal. The spectral image is coupled to CCD by lens imaging to achieve spectral display and data analysis function by computer. The system is used to detect the surface of the floating oil film in the distance of 25m to obtain the fluorescence spectra of different oil products respectively. The fluorescence spectra of oil products are obvious. The experimental results show that the system can realize high-precision long-range fluorescence detection and reflect the fluorescence characteristics of the target accurately, with broad application prospects in marine oil pollution identification and oil film thickness detection.

  9. Accurate Mass Measurements for Planetary Microlensing Events Using High Angular Resolution Observations

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Beaulieu

    2018-04-01

    Full Text Available The microlensing technique is a unique method to hunt for cold planets over a range of mass and separation, orbiting all varieties of host stars in the disk of our galaxy. It provides precise mass-ratio and projected separations in units of the Einstein ring radius. In order to obtain the physical parameters (mass, distance, orbital separation of the system, it is necessary to combine the result of light curve modeling with lens mass-distance relations and/or perform a Bayesian analysis with a galactic model. A first mass-distance relation could be obtained from a constraint on the Einstein ring radius if the crossing time of the source over the caustic is measured. It could then be supplemented by secondary constraints such as parallax measurements, ideally by using coinciding ground and space-born observations. These are still subject to degeneracies, like the orbital motion of the lens. A third mass-distance relation can be obtained thanks to constraints on the lens luminosity using high angular resolution observations with 8 m class telescopes or the Hubble Space Telescope. The latter route, although quite inexpensive in telescope time is very effective. If we have to rely heavily on Bayesian analysis and limited constraints on mass-distance relations, the physical parameters are determined to 30–40% typically. In a handful of cases, ground-space parallax is a powerful route to get stronger constraint on masses. High angular resolution observations will be able to constrain the luminosity of the lenses in the majority of the cases, and in favorable circumstances it is possible to derive physical parameters to 10% or better. Moreover, these constraints will be obtained in most of the planets to be discovered by the Euclid and WFIRST satellites. We describe here the state-of-the-art approaches to measure lens masses and distances with an emphasis on high angular resolution observations. We will discuss the challenges, recent results and

  10. Accurate screening for synthetic preservatives in beverage using high performance liquid chromatography with time-of-flight mass spectrometry

    International Nuclear Information System (INIS)

    Li Xiuqin; Zhang Feng; Sun Yanyan; Yong Wei; Chu Xiaogang; Fang Yanyan; Zweigenbaum, Jerry

    2008-01-01

    In this study, liquid chromatography time-of-flight mass spectrometry (HPLC/TOF-MS) is applied to qualitation and quantitation of 18 synthetic preservatives in beverage. The identification by HPLC/TOF-MS is accomplished with the accurate mass (the subsequent generated empirical formula) of the protonated molecules [M + H]+ or the deprotonated molecules [M - H]-, along with the accurate mass of their main fragment ions. In order to obtain sufficient sensitivity for quantitation purposes (using the protonated or deprotonated molecule) and additional qualitative mass spectrum information provided by the fragments ions, segment program of fragmentor voltages is designed in positive and negative ion mode, respectively. Accurate mass measurements are highly useful in the complex sample analyses since they allow us to achieve a high degree of specificity, often needed when other interferents are present in the matrix. The mass accuracy typically obtained is routinely better than 3 ppm. The 18 compounds behave linearly in the 0.005-5.0 mg.kg -1 concentration range, with correlation coefficient >0.996. The recoveries at the tested concentrations of 1.0 mg.kg -1 -100 mg.kg -1 are 81-106%, with coefficients of variation -1 , which are far below the required maximum residue level (MRL) for these preservatives in foodstuff. The method is suitable for routine quantitative and qualitative analyses of synthetic preservatives in foodstuff

  11. Highly Accurate and Precise Infrared Transition Frequencies of the H_3^+ Cation

    Science.gov (United States)

    Perry, Adam J.; Markus, Charles R.; Hodges, James N.; Kocheril, G. Stephen; McCall, Benjamin J.

    2016-06-01

    Calculation of ab initio potential energy surfaces for molecules to high accuracy is only manageable for a handful of molecular systems. Among them is the simplest polyatomic molecule, the H_3^+ cation. In order to achieve a high degree of accuracy (Diniz, J.R. Mohallem, A. Alijah, M. Pavanello, L. Adamowicz, O.L. Polyansky, J. Tennyson Phys. Rev. A (2013), 88, 032506 O.L. Polyansky, A. Alijah, N.F. Zobov, I.I. Mizus, R.I. Ovsyannikov, J. Tennyson, L. Lodi, T. Szidarovszky, A.G. Császár Phil. Trans. R. Soc. A (2012), 370, 5014 J.N. Hodges, A.J. Perry, P.A. Jenkins II, B.M. Siller, B.J. McCall J. Chem. Phys. (2013), 139, 164201 A.J. Perry, J.N. Hodges, C.R. Markus, G.S. Kocheril, B.J. McCall J. Molec. Spectrosc. (2015), 317, 71-73.

  12. A highly accurate boundary integral equation method for surfactant-laden drops in 3D

    Science.gov (United States)

    Sorgentone, Chiara; Tornberg, Anna-Karin

    2018-05-01

    The presence of surfactants alters the dynamics of viscous drops immersed in an ambient viscous fluid. This is specifically true at small scales, such as in applications of droplet based microfluidics, where the interface dynamics become of increased importance. At such small scales, viscous forces dominate and inertial effects are often negligible. Considering Stokes flow, a numerical method based on a boundary integral formulation is presented for simulating 3D drops covered by an insoluble surfactant. The method is able to simulate drops with different viscosities and close interactions, automatically controlling the time step size and maintaining high accuracy also when substantial drop deformation appears. To achieve this, the drop surfaces as well as the surfactant concentration on each surface are represented by spherical harmonics expansions. A novel reparameterization method is introduced to ensure a high-quality representation of the drops also under deformation, specialized quadrature methods for singular and nearly singular integrals that appear in the formulation are evoked and the adaptive time stepping scheme for the coupled drop and surfactant evolution is designed with a preconditioned implicit treatment of the surfactant diffusion.

  13. Aptamer-conjugated live human immune cell based biosensors for the accurate detection of C-reactive protein

    OpenAIRE

    Hwang, Jangsun; Seo, Youngmin; Jo, Yeonho; Son, Jaewoo; Choi, Jonghoon

    2016-01-01

    C-reactive protein (CRP) is a pentameric protein that is present in the bloodstream during inflammatory events, e.g., liver failure, leukemia, and/or bacterial infection. The level of CRP indicates the progress and prognosis of certain diseases; it is therefore necessary to measure CRP levels in the blood accurately. The normal concentration of CRP is reported to be 1?3?mg/L. Inflammatory events increase the level of CRP by up to 500 times; accordingly, CRP is a biomarker of acute inflammator...

  14. The development and verification of a highly accurate collision prediction model for automated noncoplanar plan delivery

    International Nuclear Information System (INIS)

    Yu, Victoria Y.; Tran, Angelia; Nguyen, Dan; Cao, Minsong; Ruan, Dan; Low, Daniel A.; Sheng, Ke

    2015-01-01

    Purpose: Significant dosimetric benefits had been previously demonstrated in highly noncoplanar treatment plans. In this study, the authors developed and verified an individualized collision model for the purpose of delivering highly noncoplanar radiotherapy and tested the feasibility of total delivery automation with Varian TrueBeam developer mode. Methods: A hand-held 3D scanner was used to capture the surfaces of an anthropomorphic phantom and a human subject, which were positioned with a computer-aided design model of a TrueBeam machine to create a detailed virtual geometrical collision model. The collision model included gantry, collimator, and couch motion degrees of freedom. The accuracy of the 3D scanner was validated by scanning a rigid cubical phantom with known dimensions. The collision model was then validated by generating 300 linear accelerator orientations corresponding to 300 gantry-to-couch and gantry-to-phantom distances, and comparing the corresponding distance measurements to their corresponding models. The linear accelerator orientations reflected uniformly sampled noncoplanar beam angles to the head, lung, and prostate. The distance discrepancies between measurements on the physical and virtual systems were used to estimate treatment-site-specific safety buffer distances with 0.1%, 0.01%, and 0.001% probability of collision between the gantry and couch or phantom. Plans containing 20 noncoplanar beams to the brain, lung, and prostate optimized via an in-house noncoplanar radiotherapy platform were converted into XML script for automated delivery and the entire delivery was recorded and timed to demonstrate the feasibility of automated delivery. Results: The 3D scanner measured the dimension of the 14 cm cubic phantom within 0.5 mm. The maximal absolute discrepancy between machine and model measurements for gantry-to-couch and gantry-to-phantom was 0.95 and 2.97 cm, respectively. The reduced accuracy of gantry-to-phantom measurements was

  15. The development and verification of a highly accurate collision prediction model for automated noncoplanar plan delivery

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Victoria Y.; Tran, Angelia; Nguyen, Dan; Cao, Minsong; Ruan, Dan; Low, Daniel A.; Sheng, Ke, E-mail: ksheng@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024 (United States)

    2015-11-15

    Purpose: Significant dosimetric benefits had been previously demonstrated in highly noncoplanar treatment plans. In this study, the authors developed and verified an individualized collision model for the purpose of delivering highly noncoplanar radiotherapy and tested the feasibility of total delivery automation with Varian TrueBeam developer mode. Methods: A hand-held 3D scanner was used to capture the surfaces of an anthropomorphic phantom and a human subject, which were positioned with a computer-aided design model of a TrueBeam machine to create a detailed virtual geometrical collision model. The collision model included gantry, collimator, and couch motion degrees of freedom. The accuracy of the 3D scanner was validated by scanning a rigid cubical phantom with known dimensions. The collision model was then validated by generating 300 linear accelerator orientations corresponding to 300 gantry-to-couch and gantry-to-phantom distances, and comparing the corresponding distance measurements to their corresponding models. The linear accelerator orientations reflected uniformly sampled noncoplanar beam angles to the head, lung, and prostate. The distance discrepancies between measurements on the physical and virtual systems were used to estimate treatment-site-specific safety buffer distances with 0.1%, 0.01%, and 0.001% probability of collision between the gantry and couch or phantom. Plans containing 20 noncoplanar beams to the brain, lung, and prostate optimized via an in-house noncoplanar radiotherapy platform were converted into XML script for automated delivery and the entire delivery was recorded and timed to demonstrate the feasibility of automated delivery. Results: The 3D scanner measured the dimension of the 14 cm cubic phantom within 0.5 mm. The maximal absolute discrepancy between machine and model measurements for gantry-to-couch and gantry-to-phantom was 0.95 and 2.97 cm, respectively. The reduced accuracy of gantry-to-phantom measurements was

  16. The development and verification of a highly accurate collision prediction model for automated noncoplanar plan delivery.

    Science.gov (United States)

    Yu, Victoria Y; Tran, Angelia; Nguyen, Dan; Cao, Minsong; Ruan, Dan; Low, Daniel A; Sheng, Ke

    2015-11-01

    Significant dosimetric benefits had been previously demonstrated in highly noncoplanar treatment plans. In this study, the authors developed and verified an individualized collision model for the purpose of delivering highly noncoplanar radiotherapy and tested the feasibility of total delivery automation with Varian TrueBeam developer mode. A hand-held 3D scanner was used to capture the surfaces of an anthropomorphic phantom and a human subject, which were positioned with a computer-aided design model of a TrueBeam machine to create a detailed virtual geometrical collision model. The collision model included gantry, collimator, and couch motion degrees of freedom. The accuracy of the 3D scanner was validated by scanning a rigid cubical phantom with known dimensions. The collision model was then validated by generating 300 linear accelerator orientations corresponding to 300 gantry-to-couch and gantry-to-phantom distances, and comparing the corresponding distance measurements to their corresponding models. The linear accelerator orientations reflected uniformly sampled noncoplanar beam angles to the head, lung, and prostate. The distance discrepancies between measurements on the physical and virtual systems were used to estimate treatment-site-specific safety buffer distances with 0.1%, 0.01%, and 0.001% probability of collision between the gantry and couch or phantom. Plans containing 20 noncoplanar beams to the brain, lung, and prostate optimized via an in-house noncoplanar radiotherapy platform were converted into XML script for automated delivery and the entire delivery was recorded and timed to demonstrate the feasibility of automated delivery. The 3D scanner measured the dimension of the 14 cm cubic phantom within 0.5 mm. The maximal absolute discrepancy between machine and model measurements for gantry-to-couch and gantry-to-phantom was 0.95 and 2.97 cm, respectively. The reduced accuracy of gantry-to-phantom measurements was attributed to phantom setup

  17. A highly accurate absolute gravimetric network for Albania, Kosovo and Montenegro

    Science.gov (United States)

    Ullrich, Christian; Ruess, Diethard; Butta, Hubert; Qirko, Kristaq; Pavicevic, Bozidar; Murat, Meha

    2016-04-01

    The objective of this project is to establish a basic gravity network in Albania, Kosovo and Montenegro to enable further investigations in geodetic and geophysical issues. Therefore the first time in history absolute gravity measurements were performed in these countries. The Norwegian mapping authority Kartverket is assisting the national mapping authorities in Kosovo (KCA) (Kosovo Cadastral Agency - Agjencia Kadastrale e Kosovës), Albania (ASIG) (Autoriteti Shtetëror i Informacionit Gjeohapësinor) and in Montenegro (REA) (Real Estate Administration of Montenegro - Uprava za nekretnine Crne Gore) in improving the geodetic frameworks. The gravity measurements are funded by Kartverket. The absolute gravimetric measurements were performed from BEV (Federal Office of Metrology and Surveying) with the absolute gravimeter FG5-242. As a national metrology institute (NMI) the Metrology Service of the BEV maintains the national standards for the realisation of the legal units of measurement and ensures their international equivalence and recognition. Laser and clock of the absolute gravimeter were calibrated before and after the measurements. The absolute gravimetric survey was carried out from September to October 2015. Finally all 8 scheduled stations were successfully measured: there are three stations located in Montenegro, two stations in Kosovo and three stations in Albania. The stations are distributed over the countries to establish a gravity network for each country. The vertical gradients were measured at all 8 stations with the relative gravimeter Scintrex CG5. The high class quality of some absolute gravity stations can be used for gravity monitoring activities in future. The measurement uncertainties of the absolute gravity measurements range around 2.5 micro Gal at all stations (1 microgal = 10-8 m/s2). In Montenegro the large gravity difference of 200 MilliGal between station Zabljak and Podgorica can be even used for calibration of relative gravimeters

  18. A high-order time-accurate interrogation method for time-resolved PIV

    International Nuclear Information System (INIS)

    Lynch, Kyle; Scarano, Fulvio

    2013-01-01

    A novel method is introduced for increasing the accuracy and extending the dynamic range of time-resolved particle image velocimetry (PIV). The approach extends the concept of particle tracking velocimetry by multiple frames to the pattern tracking by cross-correlation analysis as employed in PIV. The working principle is based on tracking the patterned fluid element, within a chosen interrogation window, along its individual trajectory throughout an image sequence. In contrast to image-pair interrogation methods, the fluid trajectory correlation concept deals with variable velocity along curved trajectories and non-zero tangential acceleration during the observed time interval. As a result, the velocity magnitude and its direction are allowed to evolve in a nonlinear fashion along the fluid element trajectory. The continuum deformation (namely spatial derivatives of the velocity vector) is accounted for by adopting local image deformation. The principle offers important reductions of the measurement error based on three main points: by enlarging the temporal measurement interval, the relative error becomes reduced; secondly, the random and peak-locking errors are reduced by the use of least-squares polynomial fits to individual trajectories; finally, the introduction of high-order (nonlinear) fitting functions provides the basis for reducing the truncation error. Lastly, the instantaneous velocity is evaluated as the temporal derivative of the polynomial representation of the fluid parcel position in time. The principal features of this algorithm are compared with a single-pair iterative image deformation method. Synthetic image sequences are considered with steady flow (translation, shear and rotation) illustrating the increase of measurement precision. An experimental data set obtained by time-resolved PIV measurements of a circular jet is used to verify the robustness of the method on image sequences affected by camera noise and three-dimensional motions. In

  19. An accurate and efficient system model of iterative image reconstruction in high-resolution pinhole SPECT for small animal research

    Energy Technology Data Exchange (ETDEWEB)

    Huang, P-C; Hsu, C-H [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan (China); Hsiao, I-T [Department Medical Imaging and Radiological Sciences, Chang Gung University, Tao-Yuan, Taiwan (China); Lin, K M [Medical Engineering Research Division, National Health Research Institutes, Zhunan Town, Miaoli County, Taiwan (China)], E-mail: cghsu@mx.nthu.edu.tw

    2009-06-15

    Accurate modeling of the photon acquisition process in pinhole SPECT is essential for optimizing resolution. In this work, the authors develop an accurate system model in which pinhole finite aperture and depth-dependent geometric sensitivity are explicitly included. To achieve high-resolution pinhole SPECT, the voxel size is usually set in the range of sub-millimeter so that the total number of image voxels increase accordingly. It is inevitably that a system matrix that models a variety of favorable physical factors will become extremely sophisticated. An efficient implementation for such an accurate system model is proposed in this research. We first use the geometric symmetries to reduce redundant entries in the matrix. Due to the sparseness of the matrix, only non-zero terms are stored. A novel center-to-radius recording rule is also developed to effectively describe the relation between a voxel and its related detectors at every projection angle. The proposed system matrix is also suitable for multi-threaded computing. Finally, the accuracy and effectiveness of the proposed system model is evaluated in a workstation equipped with two Quad-Core Intel X eon processors.

  20. A simple, robust and efficient high-order accurate shock-capturing scheme for compressible flows: Towards minimalism

    Science.gov (United States)

    Ohwada, Taku; Shibata, Yuki; Kato, Takuma; Nakamura, Taichi

    2018-06-01

    Developed is a high-order accurate shock-capturing scheme for the compressible Euler/Navier-Stokes equations; the formal accuracy is 5th order in space and 4th order in time. The performance and efficiency of the scheme are validated in various numerical tests. The main ingredients of the scheme are nothing special; they are variants of the standard numerical flux, MUSCL, the usual Lagrange's polynomial and the conventional Runge-Kutta method. The scheme can compute a boundary layer accurately with a rational resolution and capture a stationary contact discontinuity sharply without inner points. And yet it is endowed with high resistance against shock anomalies (carbuncle phenomenon, post-shock oscillations, etc.). A good balance between high robustness and low dissipation is achieved by blending three types of numerical fluxes according to physical situation in an intuitively easy-to-understand way. The performance of the scheme is largely comparable to that of WENO5-Rusanov, while its computational cost is 30-40% less than of that of the advanced scheme.

  1. Highly accurate Michelson type wavelength meter that uses a rubidium stabilized 1560 nm diode laser as a wavelength reference

    International Nuclear Information System (INIS)

    Masuda, Shin; Kanoh, Eiji; Irisawa, Akiyoshi; Niki, Shoji

    2009-01-01

    We investigated the accuracy limitation of a wavelength meter installed in a vacuum chamber to enable us to develop a highly accurate meter based on a Michelson interferometer in 1550 nm optical communication bands. We found that an error of parts per million order could not be avoided using famous wavelength compensation equations. Chromatic dispersion of the refractive index in air can almost be disregarded when a 1560 nm wavelength produced by a rubidium (Rb) stabilized distributed feedback (DFB) diode laser is used as a reference wavelength. We describe a novel dual-wavelength self-calibration scheme that maintains high accuracy of the wavelength meter. The method uses the fundamental and second-harmonic wavelengths of an Rb-stabilized DFB diode laser. Consequently, a highly accurate Michelson type wavelength meter with an absolute accuracy of 5x10 -8 (10 MHz, 0.08 pm) over a wide wavelength range including optical communication bands was achieved without the need for a vacuum chamber.

  2. Identifying differences in brain activities and an accurate detection of autism spectrum disorder using resting state functional-magnetic resonance imaging : A spatial filtering approach.

    Science.gov (United States)

    Subbaraju, Vigneshwaran; Suresh, Mahanand Belathur; Sundaram, Suresh; Narasimhan, Sundararajan

    2017-01-01

    This paper presents a new approach for detecting major differences in brain activities between Autism Spectrum Disorder (ASD) patients and neurotypical subjects using the resting state fMRI. Further the method also extracts discriminative features for an accurate diagnosis of ASD. The proposed approach determines a spatial filter that projects the covariance matrices of the Blood Oxygen Level Dependent (BOLD) time-series signals from both the ASD patients and neurotypical subjects in orthogonal directions such that they are highly separable. The inverse of this filter also provides a spatial pattern map within the brain that highlights those regions responsible for the distinguishable activities between the ASD patients and neurotypical subjects. For a better classification, highly discriminative log-variance features providing the maximum separation between the two classes are extracted from the projected BOLD time-series data. A detailed study has been carried out using the publicly available data from the Autism Brain Imaging Data Exchange (ABIDE) consortium for the different gender and age-groups. The study results indicate that for all the above categories, the regional differences in resting state activities are more commonly found in the right hemisphere compared to the left hemisphere of the brain. Among males, a clear shift in activities to the prefrontal cortex is observed for ASD patients while other parts of the brain show diminished activities compared to neurotypical subjects. Among females, such a clear shift is not evident; however, several regions, especially in the posterior and medial portions of the brain show diminished activities due to ASD. Finally, the classification performance obtained using the log-variance features is found to be better when compared to earlier studies in the literature. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. A novel method for accurate needle-tip identification in trans-rectal ultrasound-based high-dose-rate prostate brachytherapy.

    Science.gov (United States)

    Zheng, Dandan; Todor, Dorin A

    2011-01-01

    In real-time trans-rectal ultrasound (TRUS)-based high-dose-rate prostate brachytherapy, the accurate identification of needle-tip position is critical for treatment planning and delivery. Currently, needle-tip identification on ultrasound images can be subject to large uncertainty and errors because of ultrasound image quality and imaging artifacts. To address this problem, we developed a method based on physical measurements with simple and practical implementation to improve the accuracy and robustness of needle-tip identification. Our method uses measurements of the residual needle length and an off-line pre-established coordinate transformation factor, to calculate the needle-tip position on the TRUS images. The transformation factor was established through a one-time systematic set of measurements of the probe and template holder positions, applicable to all patients. To compare the accuracy and robustness of the proposed method and the conventional method (ultrasound detection), based on the gold-standard X-ray fluoroscopy, extensive measurements were conducted in water and gel phantoms. In water phantom, our method showed an average tip-detection accuracy of 0.7 mm compared with 1.6 mm of the conventional method. In gel phantom (more realistic and tissue-like), our method maintained its level of accuracy while the uncertainty of the conventional method was 3.4mm on average with maximum values of over 10mm because of imaging artifacts. A novel method based on simple physical measurements was developed to accurately detect the needle-tip position for TRUS-based high-dose-rate prostate brachytherapy. The method demonstrated much improved accuracy and robustness over the conventional method. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. A Modified ELISA Accurately Measures Secretion of High Molecular Weight Hyaluronan (HA) by Graves' Disease Orbital Cells

    Science.gov (United States)

    Krieger, Christine C.

    2014-01-01

    Excess production of hyaluronan (hyaluronic acid [HA]) in the retro-orbital space is a major component of Graves' ophthalmopathy, and regulation of HA production by orbital cells is a major research area. In most previous studies, HA was measured by ELISAs that used HA-binding proteins for detection and rooster comb HA as standards. We show that the binding efficiency of HA-binding protein in the ELISA is a function of HA polymer size. Using gel electrophoresis, we show that HA secreted from orbital cells is primarily comprised of polymers more than 500 000. We modified a commercially available ELISA by using 1 million molecular weight HA as standard to accurately measure HA of this size. We demonstrated that IL-1β-stimulated HA secretion is at least 2-fold greater than previously reported, and activation of the TSH receptor by an activating antibody M22 from a patient with Graves' disease led to more than 3-fold increase in HA production in both fibroblasts/preadipocytes and adipocytes. These effects were not consistently detected with the commercial ELISA using rooster comb HA as standard and suggest that fibroblasts/preadipocytes may play a more prominent role in HA remodeling in Graves' ophthalmopathy than previously appreciated. PMID:24302624

  5. A Novel Edge-Map Creation Approach for Highly Accurate Pupil Localization in Unconstrained Infrared Iris Images

    Directory of Open Access Journals (Sweden)

    Vineet Kumar

    2016-01-01

    Full Text Available Iris segmentation in the iris recognition systems is a challenging task under noncooperative environments. The iris segmentation is a process of detecting the pupil, iris’s outer boundary, and eyelids in the iris image. In this paper, we propose a pupil localization method for locating the pupils in the non-close-up and frontal-view iris images that are captured under near-infrared (NIR illuminations and contain the noise, such as specular and lighting reflection spots, eyeglasses, nonuniform illumination, low contrast, and occlusions by the eyelids, eyelashes, and eyebrow hair. In the proposed method, first, a novel edge-map is created from the iris image, which is based on combining the conventional thresholding and edge detection based segmentation techniques, and then, the general circular Hough transform (CHT is used to find the pupil circle parameters in the edge-map. Our main contribution in this research is a novel edge-map creation technique, which reduces the false edges drastically in the edge-map of the iris image and makes the pupil localization in the noisy NIR images more accurate, fast, robust, and simple. The proposed method was tested with three iris databases: CASIA-Iris-Thousand (version 4.0, CASIA-Iris-Lamp (version 3.0, and MMU (version 2.0. The average accuracy of the proposed method is 99.72% and average time cost per image is 0.727 sec.

  6. Reconstruction of high resolution MLC leaf positions using a low resolution detector for accurate 3D dose reconstruction in IMRT

    NARCIS (Netherlands)

    Visser, R; Godart, J; Wauben, D J L; Langendijk, J A; Van't Veld, A A; Korevaar, E W

    2016-01-01

    In pre-treatment dose verification, low resolution detector systems are unable to identify shifts of individual leafs of high resolution multi leaf collimator (MLC) systems from detected changes in the dose deposition. The goal of this study was to introduce an alternative approach (the shutter

  7. Detecting ultra high energy neutrinos with LOFAR

    International Nuclear Information System (INIS)

    Mevius, M.; Buitink, S.; Falcke, H.; Hörandel, J.; James, C.W.; McFadden, R.; Scholten, O.; Singh, K.; Stappers, B.; Veen, S. ter

    2012-01-01

    The NuMoon project aims to detect signals of Ultra High Energy (UHE) Cosmic Rays with radio telescopes on Earth using the Lunar Cherenkov technique at low frequencies (∼150MHz). The advantage of using low frequencies is the much larger effective detecting volume, with as trade-off the cut-off in sensitivity at lower energies. A first upper limit on the UHE neutrino flux from data of the Westerbork Radio Telescope (WSRT) has been published, while a second experiment, using the new LOFAR telescope, is in preparation. The advantages of LOFAR over WSRT are the larger collecting area, the better pointing accuracy and the use of ring buffers, which allow the implementation of a sophisticated self-trigger algorithm. The expected sensitivity of LOFAR reaches flux limits within the range of some theoretical production models.

  8. Accurate calculations of the WIMP halo around the Sun and prospects for its gamma-ray detection

    International Nuclear Information System (INIS)

    Sivertsson, Sofia; Edsjoe, Joakim

    2010-01-01

    Galactic weakly interacting massive particles (WIMPs) may scatter off solar nuclei to orbits gravitationally bound to the Sun. Once bound, the WIMPs continue to lose energy by repeated scatters in the Sun, eventually leading to complete entrapment in the solar interior. While the density of the bound population is highest at the center of the Sun, the only observable signature of WIMP annihilations inside the Sun is neutrinos. It has been previously suggested that although the density of WIMPs just outside the Sun is lower than deep inside, gamma rays from WIMP annihilation just outside the surface of the Sun, in the so-called WIMP halo around the Sun, may be more easily detected. We here revisit this problem using detailed Monte Carlo simulations and detailed composition and structure information about the Sun to estimate the size of the gamma-ray flux. Compared to earlier simpler estimates, we find that the gamma-ray flux from WIMP annihilations in the solar WIMP halo would be negligible; no current or planned detectors would be able to detect this flux.

  9. Accurate and reproducible invasive breast cancer detection in whole-slide images: A Deep Learning approach for quantifying tumor extent

    Science.gov (United States)

    Cruz-Roa, Angel; Gilmore, Hannah; Basavanhally, Ajay; Feldman, Michael; Ganesan, Shridar; Shih, Natalie N. C.; Tomaszewski, John; González, Fabio A.; Madabhushi, Anant

    2017-04-01

    With the increasing ability to routinely and rapidly digitize whole slide images with slide scanners, there has been interest in developing computerized image analysis algorithms for automated detection of disease extent from digital pathology images. The manual identification of presence and extent of breast cancer by a pathologist is critical for patient management for tumor staging and assessing treatment response. However, this process is tedious and subject to inter- and intra-reader variability. For computerized methods to be useful as decision support tools, they need to be resilient to data acquired from different sources, different staining and cutting protocols and different scanners. The objective of this study was to evaluate the accuracy and robustness of a deep learning-based method to automatically identify the extent of invasive tumor on digitized images. Here, we present a new method that employs a convolutional neural network for detecting presence of invasive tumor on whole slide images. Our approach involves training the classifier on nearly 400 exemplars from multiple different sites, and scanners, and then independently validating on almost 200 cases from The Cancer Genome Atlas. Our approach yielded a Dice coefficient of 75.86%, a positive predictive value of 71.62% and a negative predictive value of 96.77% in terms of pixel-by-pixel evaluation compared to manually annotated regions of invasive ductal carcinoma.

  10. The Stool DNA Test is More Accurate than the Plasma Septin 9 Test in Detecting Colorectal Neoplasia

    Science.gov (United States)

    Ahlquist, David A.; Taylor, William R.; Mahoney, Douglas W.; Zou, Hongzhi; Domanico, Michael; Thibodeau, Stephen N.; Boardman, Lisa A.; Berger, Barry M.; Lidgard, Graham P.

    2014-01-01

    Background & Aims Several noninvasive tests have been developed for colorectal cancer (CRC) screening. We compared the sensitivities of a multi-marker test for stool DNA (sDNA) and a plasma test for methylated Septin 9 (SEPT9) in identifying patients with large adenomas or CRC. Methods We analyzed paired stool and plasma samples from 30 patients with CRC and 22 with large adenomas from Mayo Clinic archives. Stool (n=46) and plasma (n=49) samples from age- and sex-matched patients with normal colonoscopy results were used as controls. The sDNA test is an assay for methylated BMP3, NDRG4, vimentin, and TFPI2; mutant KRAS; the β-actin gene, and quantity of hemoglobin (by the porphyrin method). It was performed blindly at Exact Sciences (Madison WI); the test for SEPT9 was performed at ARUP Laboratories (Salt Lake City UT). Results were considered positive based on the manufacturer's specificity cutoff values of 90% and 89%, respectively. Results The sDNA test detected adenomas (median 2 cm, range 1–5 cm) with 82% sensitivity (95% confidence interval [CI], 60%–95%); SEPT9 had 14% sensitivity (95% CI, 3%–35%; P=.0001). The sDNA test identified patients with CRC with 87% sensitivity (95% CI, 69%–96%); SEPT9 had 60% sensitivity (95% CI, 41%–77%; P=.046). The sDNA test identified patients with stage I–III CRC with 91% sensitivity (95% CI, 71%–99%); SEPT9 had 50% sensitivity (95% CI, 28%–72%; P=.013); for stage IV CRC, sensitivity values were 75% (95% CI, 35%–97%) and 88% (95% CI, 47%–100%), respectively (P=.56). False-positive rates were 7% for the sDNA test and 27% for SEPT9. Conclusions Based on analyses of paired samples, the sDNA test detects non-metastatic CRC and large adenomas with significantly greater levels of sensitivity than the SEPT9 test. These findings might be used to modify approaches for CRC prevention and early detection. PMID:22019796

  11. High throughput and accurate serum proteome profiling by integrated sample preparation technology and single-run data independent mass spectrometry analysis.

    Science.gov (United States)

    Lin, Lin; Zheng, Jiaxin; Yu, Quan; Chen, Wendong; Xing, Jinchun; Chen, Chenxi; Tian, Ruijun

    2018-03-01

    Mass spectrometry (MS)-based serum proteome analysis is extremely challenging due to its high complexity and dynamic range of protein abundances. Developing high throughput and accurate serum proteomic profiling approach capable of analyzing large cohorts is urgently needed for biomarker discovery. Herein, we report a streamlined workflow for fast and accurate proteomic profiling from 1μL of blood serum. The workflow combined an integrated technique for highly sensitive and reproducible sample preparation and a new data-independent acquisition (DIA)-based MS method. Comparing with standard data dependent acquisition (DDA) approach, the optimized DIA method doubled the number of detected peptides and proteins with better reproducibility. Without protein immunodepletion and prefractionation, the single-run DIA analysis enables quantitative profiling of over 300 proteins with 50min gradient time. The quantified proteins span more than five orders of magnitude of abundance range and contain over 50 FDA-approved disease markers. The workflow allowed us to analyze 20 serum samples per day, with about 358 protein groups per sample being identified. A proof-of-concept study on renal cell carcinoma (RCC) serum samples confirmed the feasibility of the workflow for large scale serum proteomic profiling and disease-related biomarker discovery. Blood serum or plasma is the predominant specimen for clinical proteomic studies while the analysis is extremely challenging for its high complexity. Many efforts had been made in the past for serum proteomics for maximizing protein identifications, whereas few have been concerned with throughput and reproducibility. Here, we establish a rapid, robust and high reproducible DIA-based workflow for streamlined serum proteomic profiling from 1μL serum. The workflow doesn't need protein depletion and pre-fractionation, while still being able to detect disease-relevant proteins accurately. The workflow is promising in clinical application

  12. DNA extraction techniques compared for accurate detection of genetically modified organisms (GMOs) in maize food and feed products.

    Science.gov (United States)

    Turkec, Aydin; Kazan, Hande; Karacanli, Burçin; Lucas, Stuart J

    2015-08-01

    In this paper, DNA extraction methods have been evaluated to detect the presence of genetically modified organisms (GMOs) in maize food and feed products commercialised in Turkey. All the extraction methods tested performed well for the majority of maize foods and feed products analysed. However, the highest DNA content was achieved by the Wizard, Genespin or the CTAB method, all of which produced optimal DNA yield and purity for different maize food and feed products. The samples were then screened for the presence of GM elements, along with certified reference materials. Of the food and feed samples, 8 % tested positive for the presence of one GM element (NOS terminator), of which half (4 % of the total) also contained a second element (the Cauliflower Mosaic Virus 35S promoter). The results obtained herein clearly demonstrate the presence of GM maize in the Turkish market, and that the Foodproof GMO Screening Kit provides reliable screening of maize food and feed products.

  13. A rapid method of accurate detection and differentiation of Newcastle disease virus pathotypes by demonstrating multiple bands in degenerate primer based nested RT-PCR.

    Science.gov (United States)

    Desingu, P A; Singh, S D; Dhama, K; Kumar, O R Vinodh; Singh, R; Singh, R K

    2015-02-01

    A rapid and accurate method of detection and differentiation of virulent and avirulent Newcastle disease virus (NDV) pathotypes was developed. The NDV detection was carried out for different domestic avian field isolates and pigeon paramyxo virus-1 (25 field isolates and 9 vaccine strains) by using APMV-I "fusion" (F) gene Class II specific external primer A and B (535bp), internal primer C and D (238bp) based reverses transcriptase PCR (RT-PCR). The internal degenerative reverse primer D is specific for F gene cleavage position of virulent strain of NDV. The nested RT-PCR products of avirulent strains showed two bands (535bp and 424bp) while virulent strains showed four bands (535bp, 424bp, 349bp and 238bp) on agar gel electrophoresis. This is the first report regarding development and use of degenerate primer based nested RT-PCR for accurate detection and differentiation of NDV pathotypes by demonstrating multiple PCR band patterns. Being a rapid, simple, and economical test, the developed method could serve as a valuable alternate diagnostic tool for characterizing NDV isolates and carrying out molecular epidemiological surveillance studies for this important pathogen of poultry. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A different interpretation of Einstein's viscosity equation provides accurate representations of the behavior of hydrophilic solutes to high concentrations.

    Science.gov (United States)

    Zavitsas, Andreas A

    2012-08-23

    Viscosities of aqueous solutions of many highly soluble hydrophilic solutes with hydroxyl and amino groups are examined with a focus on improving the concentration range over which Einstein's relationship between solution viscosity and solute volume, V, is applicable accurately. V is the hydrodynamic effective volume of the solute, including any water strongly bound to it and acting as a single entity with it. The widespread practice is to relate the relative viscosity of solute to solvent, η/η(0), to V/V(tot), where V(tot) is the total volume of the solution. For solutions that are not infinitely dilute, it is shown that the volume ratio must be expressed as V/V(0), where V(0) = V(tot) - V. V(0) is the volume of water not bound to the solute, the "free" water solvent. At infinite dilution, V/V(0) = V/V(tot). For the solutions examined, the proportionality constant between the relative viscosity and volume ratio is shown to be 2.9, rather than the 2.5 commonly used. To understand the phenomena relating to viscosity, the hydrodynamic effective volume of water is important. It is estimated to be between 54 and 85 cm(3). With the above interpretations of Einstein's equation, which are consistent with his stated reasoning, the relation between the viscosity and volume ratio remains accurate to much higher concentrations than those attainable with any of the other relations examined that express the volume ratio as V/V(tot).

  15. A Highly Accurate Regular Domain Collocation Method for Solving Potential Problems in the Irregular Doubly Connected Domains

    Directory of Open Access Journals (Sweden)

    Zhao-Qing Wang

    2014-01-01

    Full Text Available Embedding the irregular doubly connected domain into an annular regular region, the unknown functions can be approximated by the barycentric Lagrange interpolation in the regular region. A highly accurate regular domain collocation method is proposed for solving potential problems on the irregular doubly connected domain in polar coordinate system. The formulations of regular domain collocation method are constructed by using barycentric Lagrange interpolation collocation method on the regular domain in polar coordinate system. The boundary conditions are discretized by barycentric Lagrange interpolation within the regular domain. An additional method is used to impose the boundary conditions. The least square method can be used to solve the overconstrained equations. The function values of points in the irregular doubly connected domain can be calculated by barycentric Lagrange interpolation within the regular domain. Some numerical examples demonstrate the effectiveness and accuracy of the presented method.

  16. Novel high accurate sensorless dual-axis solar tracking system controlled by maximum power point tracking unit of photovoltaic systems

    International Nuclear Information System (INIS)

    Fathabadi, Hassan

    2016-01-01

    Highlights: • Novel high accurate sensorless dual-axis solar tracker. • It has the advantages of both sensor based and sensorless solar trackers. • It does not have the disadvantages of sensor based and sensorless solar trackers. • Tracking error of only 0.11° that is less than the tracking errors of others. • An increase of 28.8–43.6% depending on the seasons in the energy efficiency. - Abstract: In this study, a novel high accurate sensorless dual-axis solar tracker controlled by the maximum power point tracking unit available in almost all photovoltaic systems is proposed. The maximum power point tracking controller continuously calculates the maximum output power of the photovoltaic module/panel/array, and uses the altitude and azimuth angles deviations to track the sun direction where the greatest value of the maximum output power is extracted. Unlike all other sensorless solar trackers, the proposed solar tracking system is a closed loop system which means it uses the actual direction of the sun at any time to track the sun direction, and this is the contribution of this work. The proposed solar tracker has the advantages of both sensor based and sensorless dual-axis solar trackers, but it does not have their disadvantages. Other sensorless solar trackers all are open loop, i.e., they use offline estimated data about the sun path in the sky obtained from solar map equations, so low exactness, cloudy sky, and requiring new data for new location are their problems. A photovoltaic system has been built, and it is experimentally verified that the proposed solar tracking system tracks the sun direction with the tracking error of 0.11° which is less than the tracking errors of other both sensor based and sensorless solar trackers. An increase of 28.8–43.6% depending on the seasons in the energy efficiency is the main advantage of utilizing the proposed solar tracking system.

  17. Fast and accurate phylogenetic reconstruction from high-resolution whole-genome data and a novel robustness estimator.

    Science.gov (United States)

    Lin, Y; Rajan, V; Moret, B M E

    2011-09-01

    The rapid accumulation of whole-genome data has renewed interest in the study of genomic rearrangements. Comparative genomics, evolutionary biology, and cancer research all require models and algorithms to elucidate the mechanisms, history, and consequences of these rearrangements. However, even simple models lead to NP-hard problems, particularly in the area of phylogenetic analysis. Current approaches are limited to small collections of genomes and low-resolution data (typically a few hundred syntenic blocks). Moreover, whereas phylogenetic analyses from sequence data are deemed incomplete unless bootstrapping scores (a measure of confidence) are given for each tree edge, no equivalent to bootstrapping exists for rearrangement-based phylogenetic analysis. We describe a fast and accurate algorithm for rearrangement analysis that scales up, in both time and accuracy, to modern high-resolution genomic data. We also describe a novel approach to estimate the robustness of results-an equivalent to the bootstrapping analysis used in sequence-based phylogenetic reconstruction. We present the results of extensive testing on both simulated and real data showing that our algorithm returns very accurate results, while scaling linearly with the size of the genomes and cubically with their number. We also present extensive experimental results showing that our approach to robustness testing provides excellent estimates of confidence, which, moreover, can be tuned to trade off thresholds between false positives and false negatives. Together, these two novel approaches enable us to attack heretofore intractable problems, such as phylogenetic inference for high-resolution vertebrate genomes, as we demonstrate on a set of six vertebrate genomes with 8,380 syntenic blocks. A copy of the software is available on demand.

  18. Application of Deep Learning Architectures for Accurate and Rapid Detection of Internal Mechanical Damage of Blueberry Using Hyperspectral Transmittance Data

    Directory of Open Access Journals (Sweden)

    Zhaodi Wang

    2018-04-01

    Full Text Available Deep learning has become a widely used powerful tool in many research fields, although not much so yet in agriculture technologies. In this work, two deep convolutional neural networks (CNN, viz. Residual Network (ResNet and its improved version named ResNeXt, are used to detect internal mechanical damage of blueberries using hyperspectral transmittance data. The original structure and size of hypercubes are adapted for the deep CNN training. To ensure that the models are applicable to hypercube, we adjust the number of filters in the convolutional layers. Moreover, a total of 5 traditional machine learning algorithms, viz. Sequential Minimal Optimization (SMO, Linear Regression (LR, Random Forest (RF, Bagging and Multilayer Perceptron (MLP, are performed as the comparison experiments. In terms of model assessment, k-fold cross validation is used to indicate that the model performance does not vary with the different combination of dataset. In real-world application, selling damaged berries will lead to greater interest loss than discarding the sound ones. Thus, precision, recall, and F1-score are also used as the evaluation indicators alongside accuracy to quantify the false positive rate. The first three indicators are seldom used by investigators in the agricultural engineering domain. Furthermore, ROC curves and Precision-Recall curves are plotted to visualize the performance of classifiers. The fine-tuned ResNet/ResNeXt achieve average accuracy and F1-score of 0.8844/0.8784 and 0.8952/0.8905, respectively. Classifiers SMO/ LR/RF/Bagging/MLP obtain average accuracy and F1-score of 0.8082/0.7606/0.7314/0.7113/0.7827 and 0.8268/0.7796/0.7529/0.7339/0.7971, respectively. Two deep learning models achieve better classification performance than the traditional machine learning methods. Classification for each testing sample only takes 5.2 ms and 6.5 ms respectively for ResNet and ResNeXt, indicating that the deep learning framework has great

  19. Application of Deep Learning Architectures for Accurate and Rapid Detection of Internal Mechanical Damage of Blueberry Using Hyperspectral Transmittance Data.

    Science.gov (United States)

    Wang, Zhaodi; Hu, Menghan; Zhai, Guangtao

    2018-04-07

    Deep learning has become a widely used powerful tool in many research fields, although not much so yet in agriculture technologies. In this work, two deep convolutional neural networks (CNN), viz. Residual Network (ResNet) and its improved version named ResNeXt, are used to detect internal mechanical damage of blueberries using hyperspectral transmittance data. The original structure and size of hypercubes are adapted for the deep CNN training. To ensure that the models are applicable to hypercube, we adjust the number of filters in the convolutional layers. Moreover, a total of 5 traditional machine learning algorithms, viz. Sequential Minimal Optimization (SMO), Linear Regression (LR), Random Forest (RF), Bagging and Multilayer Perceptron (MLP), are performed as the comparison experiments. In terms of model assessment, k-fold cross validation is used to indicate that the model performance does not vary with the different combination of dataset. In real-world application, selling damaged berries will lead to greater interest loss than discarding the sound ones. Thus, precision, recall, and F1-score are also used as the evaluation indicators alongside accuracy to quantify the false positive rate. The first three indicators are seldom used by investigators in the agricultural engineering domain. Furthermore, ROC curves and Precision-Recall curves are plotted to visualize the performance of classifiers. The fine-tuned ResNet/ResNeXt achieve average accuracy and F1-score of 0.8844/0.8784 and 0.8952/0.8905, respectively. Classifiers SMO/ LR/RF/Bagging/MLP obtain average accuracy and F1-score of 0.8082/0.7606/0.7314/0.7113/0.7827 and 0.8268/0.7796/0.7529/0.7339/0.7971, respectively. Two deep learning models achieve better classification performance than the traditional machine learning methods. Classification for each testing sample only takes 5.2 ms and 6.5 ms respectively for ResNet and ResNeXt, indicating that the deep learning framework has great potential for

  20. Application of Deep Learning Architectures for Accurate and Rapid Detection of Internal Mechanical Damage of Blueberry Using Hyperspectral Transmittance Data

    Science.gov (United States)

    Hu, Menghan; Zhai, Guangtao

    2018-01-01

    Deep learning has become a widely used powerful tool in many research fields, although not much so yet in agriculture technologies. In this work, two deep convolutional neural networks (CNN), viz. Residual Network (ResNet) and its improved version named ResNeXt, are used to detect internal mechanical damage of blueberries using hyperspectral transmittance data. The original structure and size of hypercubes are adapted for the deep CNN training. To ensure that the models are applicable to hypercube, we adjust the number of filters in the convolutional layers. Moreover, a total of 5 traditional machine learning algorithms, viz. Sequential Minimal Optimization (SMO), Linear Regression (LR), Random Forest (RF), Bagging and Multilayer Perceptron (MLP), are performed as the comparison experiments. In terms of model assessment, k-fold cross validation is used to indicate that the model performance does not vary with the different combination of dataset. In real-world application, selling damaged berries will lead to greater interest loss than discarding the sound ones. Thus, precision, recall, and F1-score are also used as the evaluation indicators alongside accuracy to quantify the false positive rate. The first three indicators are seldom used by investigators in the agricultural engineering domain. Furthermore, ROC curves and Precision-Recall curves are plotted to visualize the performance of classifiers. The fine-tuned ResNet/ResNeXt achieve average accuracy and F1-score of 0.8844/0.8784 and 0.8952/0.8905, respectively. Classifiers SMO/ LR/RF/Bagging/MLP obtain average accuracy and F1-score of 0.8082/0.7606/0.7314/0.7113/0.7827 and 0.8268/0.7796/0.7529/0.7339/0.7971, respectively. Two deep learning models achieve better classification performance than the traditional machine learning methods. Classification for each testing sample only takes 5.2 ms and 6.5 ms respectively for ResNet and ResNeXt, indicating that the deep learning framework has great potential for

  1. Accurate prediction of complex free surface flow around a high speed craft using a single-phase level set method

    Science.gov (United States)

    Broglia, Riccardo; Durante, Danilo

    2017-11-01

    This paper focuses on the analysis of a challenging free surface flow problem involving a surface vessel moving at high speeds, or planing. The investigation is performed using a general purpose high Reynolds free surface solver developed at CNR-INSEAN. The methodology is based on a second order finite volume discretization of the unsteady Reynolds-averaged Navier-Stokes equations (Di Mascio et al. in A second order Godunov—type scheme for naval hydrodynamics, Kluwer Academic/Plenum Publishers, Dordrecht, pp 253-261, 2001; Proceedings of 16th international offshore and polar engineering conference, San Francisco, CA, USA, 2006; J Mar Sci Technol 14:19-29, 2009); air/water interface dynamics is accurately modeled by a non standard level set approach (Di Mascio et al. in Comput Fluids 36(5):868-886, 2007a), known as the single-phase level set method. In this algorithm the governing equations are solved only in the water phase, whereas the numerical domain in the air phase is used for a suitable extension of the fluid dynamic variables. The level set function is used to track the free surface evolution; dynamic boundary conditions are enforced directly on the interface. This approach allows to accurately predict the evolution of the free surface even in the presence of violent breaking waves phenomena, maintaining the interface sharp, without any need to smear out the fluid properties across the two phases. This paper is aimed at the prediction of the complex free-surface flow field generated by a deep-V planing boat at medium and high Froude numbers (from 0.6 up to 1.2). In the present work, the planing hull is treated as a two-degree-of-freedom rigid object. Flow field is characterized by the presence of thin water sheets, several energetic breaking waves and plungings. The computational results include convergence of the trim angle, sinkage and resistance under grid refinement; high-quality experimental data are used for the purposes of validation, allowing to

  2. Fast, accurate, and robust automatic marker detection for motion correction based on oblique kV or MV projection image pairs

    International Nuclear Information System (INIS)

    Slagmolen, Pieter; Hermans, Jeroen; Maes, Frederik; Budiharto, Tom; Haustermans, Karin; Heuvel, Frank van den

    2010-01-01

    Purpose: A robust and accurate method that allows the automatic detection of fiducial markers in MV and kV projection image pairs is proposed. The method allows to automatically correct for inter or intrafraction motion. Methods: Intratreatment MV projection images are acquired during each of five treatment beams of prostate cancer patients with four implanted fiducial markers. The projection images are first preprocessed using a series of marker enhancing filters. 2D candidate marker locations are generated for each of the filtered projection images and 3D candidate marker locations are reconstructed by pairing candidates in subsequent projection images. The correct marker positions are retrieved in 3D by the minimization of a cost function that combines 2D image intensity and 3D geometric or shape information for the entire marker configuration simultaneously. This optimization problem is solved using dynamic programming such that the globally optimal configuration for all markers is always found. Translational interfraction and intrafraction prostate motion and the required patient repositioning is assessed from the position of the centroid of the detected markers in different MV image pairs. The method was validated on a phantom using CT as ground-truth and on clinical data sets of 16 patients using manual marker annotations as ground-truth. Results: The entire setup was confirmed to be accurate to around 1 mm by the phantom measurements. The reproducibility of the manual marker selection was less than 3.5 pixels in the MV images. In patient images, markers were correctly identified in at least 99% of the cases for anterior projection images and 96% of the cases for oblique projection images. The average marker detection accuracy was 1.4±1.8 pixels in the projection images. The centroid of all four reconstructed marker positions in 3D was positioned within 2 mm of the ground-truth position in 99.73% of all cases. Detecting four markers in a pair of MV images

  3. A simple highly accurate field-line mapping technique for three-dimensional Monte Carlo modeling of plasma edge transport

    International Nuclear Information System (INIS)

    Feng, Y.; Sardei, F.; Kisslinger, J.

    2005-01-01

    The paper presents a new simple and accurate numerical field-line mapping technique providing a high-quality representation of field lines as required by a Monte Carlo modeling of plasma edge transport in the complex magnetic boundaries of three-dimensional (3D) toroidal fusion devices. Using a toroidal sequence of precomputed 3D finite flux-tube meshes, the method advances field lines through a simple bilinear, forward/backward symmetric interpolation at the interfaces between two adjacent flux tubes. It is a reversible field-line mapping (RFLM) algorithm ensuring a continuous and unique reconstruction of field lines at any point of the 3D boundary. The reversibility property has a strong impact on the efficiency of modeling the highly anisotropic plasma edge transport in general closed or open configurations of arbitrary ergodicity as it avoids artificial cross-field diffusion of the fast parallel transport. For stellarator-symmetric magnetic configurations, which are the standard case for stellarators, the reversibility additionally provides an average cancellation of the radial interpolation errors of field lines circulating around closed magnetic flux surfaces. The RFLM technique has been implemented in the 3D edge transport code EMC3-EIRENE and is used routinely for plasma transport modeling in the boundaries of several low-shear and high-shear stellarators as well as in the boundary of a tokamak with 3D magnetic edge perturbations

  4. A high-density SNP map for accurate mapping of seed fibre QTL in Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Liezhao Liu

    Full Text Available A high density genetic linkage map for the complex allotetraploid crop species Brassica napus (oilseed rape was constructed in a late-generation recombinant inbred line (RIL population, using genome-wide single nucleotide polymorphism (SNP markers assayed by the Brassica 60 K Infinium BeadChip Array. The linkage map contains 9164 SNP markers covering 1832.9 cM. 1232 bins account for 7648 of the markers. A subset of 2795 SNP markers, with an average distance of 0.66 cM between adjacent markers, was applied for QTL mapping of seed colour and the cell wall fiber components acid detergent lignin (ADL, cellulose and hemicellulose. After phenotypic analyses across four different environments a total of 11 QTL were detected for seed colour and fiber traits. The high-density map considerably improved QTL resolution compared to the previous low-density maps. A previously identified major QTL with very high effects on seed colour and ADL was pinpointed to a narrow genome interval on chromosome A09, while a minor QTL explaining 8.1% to 14.1% of variation for ADL was detected on chromosome C05. Five and three QTL accounting for 4.7% to 21.9% and 7.3% to 16.9% of the phenotypic variation for cellulose and hemicellulose, respectively, were also detected. To our knowledge this is the first description of QTL for seed cellulose and hemicellulose in B. napus, representing interesting new targets for improving oil content. The high density SNP genetic map enables navigation from interesting B. napus QTL to Brassica genome sequences, giving useful new information for understanding the genetics of key seed quality traits in rapeseed.

  5. Accurate and High-Coverage Immune Repertoire Sequencing Reveals Characteristics of Antibody Repertoire Diversification in Young Children with Malaria

    Science.gov (United States)

    Jiang, Ning

    Accurately measuring the immune repertoire sequence composition, diversity, and abundance is important in studying repertoire response in infections, vaccinations, and cancer immunology. Using molecular identifiers (MIDs) to tag mRNA molecules is an effective method in improving the accuracy of immune repertoire sequencing (IR-seq). However, it is still difficult to use IR-seq on small amount of clinical samples to achieve a high coverage of the repertoire diversities. This is especially challenging in studying infections and vaccinations where B cell subpopulations with fewer cells, such as memory B cells or plasmablasts, are often of great interest to study somatic mutation patterns and diversity changes. Here, we describe an approach of IR-seq based on the use of MIDs in combination with a clustering method that can reveal more than 80% of the antibody diversity in a sample and can be applied to as few as 1,000 B cells. We applied this to study the antibody repertoires of young children before and during an acute malaria infection. We discovered unexpectedly high levels of somatic hypermutation (SHM) in infants and revealed characteristics of antibody repertoire development in young children that would have a profound impact on immunization in children.

  6. Tensor-decomposed vibrational coupled-cluster theory: Enabling large-scale, highly accurate vibrational-structure calculations

    Science.gov (United States)

    Madsen, Niels Kristian; Godtliebsen, Ian H.; Losilla, Sergio A.; Christiansen, Ove

    2018-01-01

    A new implementation of vibrational coupled-cluster (VCC) theory is presented, where all amplitude tensors are represented in the canonical polyadic (CP) format. The CP-VCC algorithm solves the non-linear VCC equations without ever constructing the amplitudes or error vectors in full dimension but still formally includes the full parameter space of the VCC[n] model in question resulting in the same vibrational energies as the conventional method. In a previous publication, we have described the non-linear-equation solver for CP-VCC calculations. In this work, we discuss the general algorithm for evaluating VCC error vectors in CP format including the rank-reduction methods used during the summation of the many terms in the VCC amplitude equations. Benchmark calculations for studying the computational scaling and memory usage of the CP-VCC algorithm are performed on a set of molecules including thiadiazole and an array of polycyclic aromatic hydrocarbons. The results show that the reduced scaling and memory requirements of the CP-VCC algorithm allows for performing high-order VCC calculations on systems with up to 66 vibrational modes (anthracene), which indeed are not possible using the conventional VCC method. This paves the way for obtaining highly accurate vibrational spectra and properties of larger molecules.

  7. High-Throughput Accurate Single-Cell Screening of Euglena gracilis with Fluorescence-Assisted Optofluidic Time-Stretch Microscopy.

    Directory of Open Access Journals (Sweden)

    Baoshan Guo

    Full Text Available The development of reliable, sustainable, and economical sources of alternative fuels is an important, but challenging goal for the world. As an alternative to liquid fossil fuels, algal biofuel is expected to play a key role in alleviating global warming since algae absorb atmospheric CO2 via photosynthesis. Among various algae for fuel production, Euglena gracilis is an attractive microalgal species as it is known to produce wax ester (good for biodiesel and aviation fuel within lipid droplets. To date, while there exist many techniques for inducing microalgal cells to produce and accumulate lipid with high efficiency, few analytical methods are available for characterizing a population of such lipid-accumulated microalgae including E. gracilis with high throughout, high accuracy, and single-cell resolution simultaneously. Here we demonstrate high-throughput, high-accuracy, single-cell screening of E. gracilis with fluorescence-assisted optofluidic time-stretch microscopy-a method that combines the strengths of microfluidic cell focusing, optical time-stretch microscopy, and fluorescence detection used in conventional flow cytometry. Specifically, our fluorescence-assisted optofluidic time-stretch microscope consists of an optical time-stretch microscope and a fluorescence analyzer on top of a hydrodynamically focusing microfluidic device and can detect fluorescence from every E. gracilis cell in a population and simultaneously obtain its image with a high throughput of 10,000 cells/s. With the multi-dimensional information acquired by the system, we classify nitrogen-sufficient (ordinary and nitrogen-deficient (lipid-accumulated E. gracilis cells with a low false positive rate of 1.0%. This method holds promise for evaluating cultivation techniques and selective breeding for microalgae-based biofuel production.

  8. Highly sensitive detection using microring resonator and nanopores

    Science.gov (United States)

    Bougot-Robin, K.; Hoste, J. W.; Le Thomas, N.; Bienstman, P.; Edel, J. B.

    2016-04-01

    One of the most significant challenges facing physical and biological scientists is the accurate detection and identification of single molecules in free-solution environments. The ability to perform such sensitive and selective measurements opens new avenues for a large number of applications in biological, medical and chemical analysis, where small sample volumes and low analyte concentrations are the norm. Access to information at the single or few molecules scale is rendered possible by a fine combination of recent advances in technologies. We propose a novel detection method that combines highly sensitive label-free resonant sensing obtained with high-Q microcavities and position control in nanoscale pores (nanopores). In addition to be label-free and highly sensitive, our technique is immobilization free and does not rely on surface biochemistry to bind probes on a chip. This is a significant advantage, both in term of biology uncertainties and fewer biological preparation steps. Through combination of high-Q photonic structures with translocation through nanopore at the end of a pipette, or through a solid-state membrane, we believe significant advances can be achieved in the field of biosensing. Silicon microrings are highly advantageous in term of sensitivity, multiplexing, and microfabrication and are chosen for this study. In term of nanopores, we both consider nanopore at the end of a nanopipette, with the pore being approach from the pipette with nanoprecise mechanical control. Alternatively, solid state nanopores can be fabricated through a membrane, supporting the ring. Both configuration are discussed in this paper, in term of implementation and sensitivity.

  9. Improved Detection System Description and New Method for Accurate Calibration of Micro-Channel Plate Based Instruments and Its Use in the Fast Plasma Investigation on NASA's Magnetospheric MultiScale Mission

    Science.gov (United States)

    Gliese, U.; Avanov, L. A.; Barrie, A. C.; Kujawski, J. T.; Mariano, A. J.; Tucker, C. J.; Chornay, D. J.; Cao, N. T.; Gershman, D. J.; Dorelli, J. C.; hide

    2015-01-01

    system calibration method that enables accurate and repeatable measurement and calibration of MCP gain, MCP efficiency, signal loss due to variation in gain and efficiency, crosstalk from effects both above and below the MCP, noise margin, and stability margin in one single measurement. More precise calibration is highly desirable as the instruments will produce higher quality raw data that will require less post-acquisition data correction using results from in-flight pitch angle distribution measurements and ground calibration measurements. The detection system description and the fundamental concepts of this new calibration method, named threshold scan, will be presented. It will be shown how to derive all the individual detection system parameters and how to choose the optimum detection system operating point. This new method has been successfully applied to achieve a highly accurate calibration of the DESs and DISs of the MMS mission. The practical application of the method will be presented together with the achieved calibration results and their significance. Finally, it will be shown that, with further detailed modeling, this method can be extended for use in flight to achieve and maintain a highly accurate detection system calibration across a large number of instruments during the mission.

  10. Detection and quantitation of trace phenolphthalein (in pharmaceutical preparations and in forensic exhibits) by liquid chromatography-tandem mass spectrometry, a sensitive and accurate method.

    Science.gov (United States)

    Sharma, Kakali; Sharma, Shiba P; Lahiri, Sujit C

    2013-01-01

    Phenolphthalein, an acid-base indicator and laxative, is important as a constituent of widely used weight-reducing multicomponent food formulations. Phenolphthalein is an useful reagent in forensic science for the identification of blood stains of suspected victims and for apprehending erring officials accepting bribes in graft or trap cases. The pink-colored alkaline hand washes originating from the phenolphthalein-smeared notes can easily be determined spectrophotometrically. But in many cases, colored solution turns colorless with time, which renders the genuineness of bribe cases doubtful to the judiciary. No method is known till now for the detection and identification of phenolphthalein in colorless forensic exhibits with positive proof. Liquid chromatography-tandem mass spectrometry had been found to be most sensitive, accurate method capable of detection and quantitation of trace phenolphthalein in commercial formulations and colorless forensic exhibits with positive proof. The detection limit of phenolphthalein was found to be 1.66 pg/L or ng/mL, and the calibration curve shows good linearity (r(2) = 0.9974). © 2012 American Academy of Forensic Sciences.

  11. A highly accurate dynamic contact angle algorithm for drops on inclined surface based on ellipse-fitting.

    Science.gov (United States)

    Xu, Z N; Wang, S Y

    2015-02-01

    To improve the accuracy in the calculation of dynamic contact angle for drops on the inclined surface, a significant number of numerical drop profiles on the inclined surface with different inclination angles, drop volumes, and contact angles are generated based on the finite difference method, a least-squares ellipse-fitting algorithm is used to calculate the dynamic contact angle. The influences of the above three factors are systematically investigated. The results reveal that the dynamic contact angle errors, including the errors of the left and right contact angles, evaluated by the ellipse-fitting algorithm tend to increase with inclination angle/drop volume/contact angle. If the drop volume and the solid substrate are fixed, the errors of the left and right contact angles increase with inclination angle. After performing a tremendous amount of computation, the critical dimensionless drop volumes corresponding to the critical contact angle error are obtained. Based on the values of the critical volumes, a highly accurate dynamic contact angle algorithm is proposed and fully validated. Within nearly the whole hydrophobicity range, it can decrease the dynamic contact angle error in the inclined plane method to less than a certain value even for different types of liquids.

  12. Helicopter Based Magnetic Detection Of Wells At The Teapot Dome (Naval Petroleum Reserve No. 3 Oilfield: Rapid And Accurate Geophysical Algorithms For Locating Wells

    Science.gov (United States)

    Harbert, W.; Hammack, R.; Veloski, G.; Hodge, G.

    2011-12-01

    In this study Airborne magnetic data was collected by Fugro Airborne Surveys from a helicopter platform (Figure 1) using the Midas II system over the 39 km2 NPR3 (Naval Petroleum Reserve No. 3) oilfield in east-central Wyoming. The Midas II system employs two Scintrex CS-2 cesium vapor magnetometers on opposite ends of a transversely mounted, 13.4-m long horizontal boom located amidships (Fig. 1). Each magnetic sensor had an in-flight sensitivity of 0.01 nT. Real time compensation of the magnetic data for magnetic noise induced by maneuvering of the aircraft was accomplished using two fluxgate magnetometers mounted just inboard of the cesium sensors. The total area surveyed was 40.5 km2 (NPR3) near Casper, Wyoming. The purpose of the survey was to accurately locate wells that had been drilled there during more than 90 years of continuous oilfield operation. The survey was conducted at low altitude and with closely spaced flight lines to improve the detection of wells with weak magnetic response and to increase the resolution of closely spaced wells. The survey was in preparation for a planned CO2 flood to enhance oil recovery, which requires a complete well inventory with accurate locations for all existing wells. The magnetic survey was intended to locate wells that are missing from the well database and to provide accurate locations for all wells. The well location method used combined an input dataset (for example, leveled total magnetic field reduced to the pole), combined with first and second horizontal spatial derivatives of this input dataset, which were then analyzed using focal statistics and finally combined using a fuzzy combination operation. Analytic signal and the Shi and Butt (2004) ZS attribute were also analyzed using this algorithm. A parameter could be adjusted to determine sensitivity. Depending on the input dataset 88% to 100% of the wells were located, with typical values being 95% to 99% for the NPR3 field site.

  13. Highly sensitive detection of a current ripple

    International Nuclear Information System (INIS)

    Aoki, Takashi; Gushiken, Tutomu; Nishikigouri, Kazutaka; Kumada, Masayuki.

    1996-01-01

    In the HIMAC, there are six thyristor-controlled power sources for driving two synchrotrons. These power sources are the three-output terminal power sources which are equipped with positive output, negative output and neutral point for the common mode countermeasures. As electromagnet circuits are connected to the three-output terminal power sources, those are three-line type. In the inside of the power source circuits controlled by thyristors, there is the oscillation peculiar to the power sources, and the variation of voltage induces current spikes. This time, in order to assess the results of the common mode countermeasures in the power source and electromagnet circuits, as one method of cross-check, it is considered that since electromagnet current flows being divided to the bridging resistance and the coil, if attention is paid to the current on bridging resistance side, the ripple components of common mode and normal mode can be detected with high sensitivity, and this was verified. The present state of heightening the performance of synchrotron power sources is explained. The cross-check of the method of assessing the performance of electromagnet power sources is reported. The method of measuring ripple current and the results of the measurement are reported. (K.I.)

  14. Fluctuation localization imaging-based fluorescence in situ hybridization (fliFISH) for accurate detection and counting of RNA copies in single cells

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Yi; Hu, Dehong; Markillie, Lye Meng; Chrisler, William B.; Gaffrey, Matthew J.; Ansong, Charles; Sussel, Lori; Orr, Galya

    2017-10-04

    Quantitative gene expression analysis in intact single cells can be achieved using single molecule- based fluorescence in situ hybridization (smFISH). This approach relies on fluorescence intensity to distinguish between true signals, emitted from an RNA copy hybridized with multiple FISH sub-probes, and background noise. Thus, the precision in smFISH is often compromised by partial or nonspecific binding of sub-probes and tissue autofluorescence, limiting its accuracy. Here we provide an accurate approach for setting quantitative thresholds between true and false signals, which relies on blinking frequencies of photoswitchable dyes. This fluctuation localization imaging-based FISH (fliFISH) uses blinking frequency patterns, emitted from a transcript bound to multiple sub-probes, which are distinct from blinking patterns emitted from partial or nonspecifically bound sub-probes and autofluorescence. Using multicolor fliFISH, we identified radial gene expression patterns in mouse pancreatic islets for insulin, the transcription factor, NKX2-2, and their ratio (Nkx2-2/Ins2). These radial patterns, showing higher values in β cells at the islet core and lower values in peripheral cells, were lost in diabetic mouse islets. In summary, fliFISH provides an accurate, quantitative approach for detecting and counting true RNA copies and rejecting false signals by their distinct blinking frequency patterns, laying the foundation for reliable single-cell transcriptomics.

  15. A standardized framework for accurate, high-throughput genotyping of recombinant and non-recombinant viral sequences.

    Science.gov (United States)

    Alcantara, Luiz Carlos Junior; Cassol, Sharon; Libin, Pieter; Deforche, Koen; Pybus, Oliver G; Van Ranst, Marc; Galvão-Castro, Bernardo; Vandamme, Anne-Mieke; de Oliveira, Tulio

    2009-07-01

    Human immunodeficiency virus type-1 (HIV-1), hepatitis B and C and other rapidly evolving viruses are characterized by extremely high levels of genetic diversity. To facilitate diagnosis and the development of prevention and treatment strategies that efficiently target the diversity of these viruses, and other pathogens such as human T-lymphotropic virus type-1 (HTLV-1), human herpes virus type-8 (HHV8) and human papillomavirus (HPV), we developed a rapid high-throughput-genotyping system. The method involves the alignment of a query sequence with a carefully selected set of pre-defined reference strains, followed by phylogenetic analysis of multiple overlapping segments of the alignment using a sliding window. Each segment of the query sequence is assigned the genotype and sub-genotype of the reference strain with the highest bootstrap (>70%) and bootscanning (>90%) scores. Results from all windows are combined and displayed graphically using color-coded genotypes. The new Virus-Genotyping Tools provide accurate classification of recombinant and non-recombinant viruses and are currently being assessed for their diagnostic utility. They have incorporated into several HIV drug resistance algorithms including the Stanford (http://hivdb.stanford.edu) and two European databases (http://www.umcutrecht.nl/subsite/spread-programme/ and http://www.hivrdb.org.uk/) and have been successfully used to genotype a large number of sequences in these and other databases. The tools are a PHP/JAVA web application and are freely accessible on a number of servers including: http://bioafrica.mrc.ac.za/rega-genotype/html/, http://lasp.cpqgm.fiocruz.br/virus-genotype/html/, http://jose.med.kuleuven.be/genotypetool/html/.

  16. Heap: a highly sensitive and accurate SNP detection tool for low-coverage high-throughput sequencing data

    KAUST Repository

    Kobayashi, Masaaki; Ohyanagi, Hajime; Takanashi, Hideki; Asano, Satomi; Kudo, Toru; Kajiya-Kanegae, Hiromi; Nagano, Atsushi J.; Tainaka, Hitoshi; Tokunaga, Tsuyoshi; Sazuka, Takashi; Iwata, Hiroyoshi; Tsutsumi, Nobuhiro; Yano, Kentaro

    2017-01-01

    and GP depends on not only their mathematical models, but the quality and quantity of variants employed in the analysis. In NGS single nucleotide polymorphism (SNP) calling, conventional tools ideally require more reads for higher SNP sensitivity

  17. An application of a relational database system for high-throughput prediction of elemental compositions from accurate mass values.

    Science.gov (United States)

    Sakurai, Nozomu; Ara, Takeshi; Kanaya, Shigehiko; Nakamura, Yukiko; Iijima, Yoko; Enomoto, Mitsuo; Motegi, Takeshi; Aoki, Koh; Suzuki, Hideyuki; Shibata, Daisuke

    2013-01-15

    High-accuracy mass values detected by high-resolution mass spectrometry analysis enable prediction of elemental compositions, and thus are used for metabolite annotations in metabolomic studies. Here, we report an application of a relational database to significantly improve the rate of elemental composition predictions. By searching a database of pre-calculated elemental compositions with fixed kinds and numbers of atoms, the approach eliminates redundant evaluations of the same formula that occur in repeated calculations with other tools. When our approach is compared with HR2, which is one of the fastest tools available, our database search times were at least 109 times shorter than those of HR2. When a solid-state drive (SSD) was applied, the search time was 488 times shorter at 5 ppm mass tolerance and 1833 times at 0.1 ppm. Even if the search by HR2 was performed with 8 threads in a high-spec Windows 7 PC, the database search times were at least 26 and 115 times shorter without and with the SSD. These improvements were enhanced in a low spec Windows XP PC. We constructed a web service 'MFSearcher' to query the database in a RESTful manner. Available for free at http://webs2.kazusa.or.jp/mfsearcher. The web service is implemented in Java, MySQL, Apache and Tomcat, with all major browsers supported. sakurai@kazusa.or.jp Supplementary data are available at Bioinformatics online.

  18. High Fidelity Non-Gravitational Force Models for Precise and Accurate Orbit Determination of TerraSAR-X

    Science.gov (United States)

    Hackel, Stefan; Montenbruck, Oliver; Steigenberger, -Peter; Eineder, Michael; Gisinger, Christoph

    Remote sensing satellites support a broad range of scientific and commercial applications. The two radar imaging satellites TerraSAR-X and TanDEM-X provide spaceborne Synthetic Aperture Radar (SAR) and interferometric SAR data with a very high accuracy. The increasing demand for precise radar products relies on sophisticated validation methods, which require precise and accurate orbit products. Basically, the precise reconstruction of the satellite’s trajectory is based on the Global Positioning System (GPS) measurements from a geodetic-grade dual-frequency receiver onboard the spacecraft. The Reduced Dynamic Orbit Determination (RDOD) approach utilizes models for the gravitational and non-gravitational forces. Following a proper analysis of the orbit quality, systematics in the orbit products have been identified, which reflect deficits in the non-gravitational force models. A detailed satellite macro model is introduced to describe the geometry and the optical surface properties of the satellite. Two major non-gravitational forces are the direct and the indirect Solar Radiation Pressure (SRP). Due to the dusk-dawn orbit configuration of TerraSAR-X, the satellite is almost constantly illuminated by the Sun. Therefore, the direct SRP has an effect on the lateral stability of the determined orbit. The indirect effect of the solar radiation principally contributes to the Earth Radiation Pressure (ERP). The resulting force depends on the sunlight, which is reflected by the illuminated Earth surface in the visible, and the emission of the Earth body in the infrared spectra. Both components of ERP require Earth models to describe the optical properties of the Earth surface. Therefore, the influence of different Earth models on the orbit quality is assessed within the presentation. The presentation highlights the influence of non-gravitational force and satellite macro models on the orbit quality of TerraSAR-X.

  19. An optimized method for neurotransmitters and their metabolites analysis in mouse hypothalamus by high performance liquid chromatography-Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry.

    Science.gov (United States)

    Yang, Zong-Lin; Li, Hui; Wang, Bing; Liu, Shu-Ying

    2016-02-15

    Neurotransmitters (NTs) and their metabolites are known to play an essential role in maintaining various physiological functions in nervous system. However, there are many difficulties in the detection of NTs together with their metabolites in biological samples. A new method for NTs and their metabolites detection by high performance liquid chromatography coupled with Q Exactive hybrid quadruple-orbitrap high-resolution accurate mass spectrometry (HPLC-HRMS) was established in this paper. This method was a great development of the applying of Q Exactive MS in the quantitative analysis. This method enabled a rapid quantification of ten compounds within 18min. Good linearity was obtained with a correlation coefficient above 0.99. The concentration range of the limit of detection (LOD) and the limit of quantitation (LOQ) level were 0.0008-0.05nmol/mL and 0.002-25.0nmol/mL respectively. Precisions (relative standard deviation, RSD) of this method were at 0.36-12.70%. Recovery ranges were between 81.83% and 118.04%. Concentrations of these compounds in mouse hypothalamus were detected by Q Exactive LC-MS technology with this method. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Enzymic colorimetry-based DNA chip: a rapid and accurate assay for detecting mutations for clarithromycin resistance in the 23S rRNA gene of Helicobacter pylori.

    Science.gov (United States)

    Xuan, Shi-Hai; Zhou, Yu-Gui; Shao, Bo; Cui, Ya-Lin; Li, Jian; Yin, Hong-Bo; Song, Xiao-Ping; Cong, Hui; Jing, Feng-Xiang; Jin, Qing-Hui; Wang, Hui-Min; Zhou, Jie

    2009-11-01

    Macrolide drugs, such as clarithromycin (CAM), are a key component of many combination therapies used to eradicate Helicobacter pylori. However, resistance to CAM is increasing in H. pylori and is becoming a serious problem in H. pylori eradication therapy. CAM resistance in H. pylori is mostly due to point mutations (A2142G/C, A2143G) in the peptidyltransferase-encoding region of the 23S rRNA gene. In this study an enzymic colorimetry-based DNA chip was developed to analyse single-nucleotide polymorphisms of the 23S rRNA gene to determine the prevalence of mutations in CAM-related resistance in H. pylori-positive patients. The results of the colorimetric DNA chip were confirmed by direct DNA sequencing. In 63 samples, the incidence of the A2143G mutation was 17.46 % (11/63). The results of the colorimetric DNA chip were concordant with DNA sequencing in 96.83 % of results (61/63). The colorimetric DNA chip could detect wild-type and mutant signals at every site, even at a DNA concentration of 1.53 x 10(2) copies microl(-1). Thus, the colorimetric DNA chip is a reliable assay for rapid and accurate detection of mutations in the 23S rRNA gene of H. pylori that lead to CAM-related resistance, directly from gastric tissues.

  1. HeurAA: accurate and fast detection of genetic variations with a novel heuristic amplicon aligner program for next generation sequencing.

    Directory of Open Access Journals (Sweden)

    Lőrinc S Pongor

    Full Text Available Next generation sequencing (NGS of PCR amplicons is a standard approach to detect genetic variations in personalized medicine such as cancer diagnostics. Computer programs used in the NGS community often miss insertions and deletions (indels that constitute a large part of known human mutations. We have developed HeurAA, an open source, heuristic amplicon aligner program. We tested the program on simulated datasets as well as experimental data from multiplex sequencing of 40 amplicons in 12 oncogenes collected on a 454 Genome Sequencer from lung cancer cell lines. We found that HeurAA can accurately detect all indels, and is more than an order of magnitude faster than previous programs. HeurAA can compare reads and reference sequences up to several thousand base pairs in length, and it can evaluate data from complex mixtures containing reads of different gene-segments from different samples. HeurAA is written in C and Perl for Linux operating systems, the code and the documentation are available for research applications at http://sourceforge.net/projects/heuraa/

  2. Detection of Subtle Context-Dependent Model Inaccuracies in High-Dimensional Robot Domains.

    Science.gov (United States)

    Mendoza, Juan Pablo; Simmons, Reid; Veloso, Manuela

    2016-12-01

    Autonomous robots often rely on models of their sensing and actions for intelligent decision making. However, when operating in unconstrained environments, the complexity of the world makes it infeasible to create models that are accurate in every situation. This article addresses the problem of using potentially large and high-dimensional sets of robot execution data to detect situations in which a robot model is inaccurate-that is, detecting context-dependent model inaccuracies in a high-dimensional context space. To find inaccuracies tractably, the robot conducts an informed search through low-dimensional projections of execution data to find parametric Regions of Inaccurate Modeling (RIMs). Empirical evidence from two robot domains shows that this approach significantly enhances the detection power of existing RIM-detection algorithms in high-dimensional spaces.

  3. High sensitivity neutron bursts detecting system

    International Nuclear Information System (INIS)

    Shyam, A.; Kaushik, T.C.; Srinivasan, M.; Kulkarni, L.V.

    1993-01-01

    Technique and instrumentation to detect multiplicity of fast neutrons, emitted in sharp bursts, has been developed. A bank of 16 BF 3 detectors, in an appropriate thermalising assembly, efficiency ∼ 16%, is used to detect neutron bursts. The output from this setup, through appropriate electronics, is divided into two paths. The first is directly connected to a computer controlled scalar. The second is connected to another similar scalar through a delay time unit (DTU). The DTU design is such that once it is triggered by a count pulse than it does not allow any counts to be recorded for a fixed dead time set at ∼ 100 μs. The difference in counts recorded directly and through DTU gives the total number of neutrons produced in bursts. This setup is being used to study lattice cracking, anomalous effects in solid deuterium systems and various reactor physics experiments. (author). 3 refs., 1 fig

  4. Rapid Classification and Identification of Multiple Microorganisms with Accurate Statistical Significance via High-Resolution Tandem Mass Spectrometry.

    Science.gov (United States)

    Alves, Gelio; Wang, Guanghui; Ogurtsov, Aleksey Y; Drake, Steven K; Gucek, Marjan; Sacks, David B; Yu, Yi-Kuo

    2018-06-05

    Rapid and accurate identification and classification of microorganisms is of paramount importance to public health and safety. With the advance of mass spectrometry (MS) technology, the speed of identification can be greatly improved. However, the increasing number of microbes sequenced is complicating correct microbial identification even in a simple sample due to the large number of candidates present. To properly untwine candidate microbes in samples containing one or more microbes, one needs to go beyond apparent morphology or simple "fingerprinting"; to correctly prioritize the candidate microbes, one needs to have accurate statistical significance in microbial identification. We meet these challenges by using peptide-centric representations of microbes to better separate them and by augmenting our earlier analysis method that yields accurate statistical significance. Here, we present an updated analysis workflow that uses tandem MS (MS/MS) spectra for microbial identification or classification. We have demonstrated, using 226 MS/MS publicly available data files (each containing from 2500 to nearly 100,000 MS/MS spectra) and 4000 additional MS/MS data files, that the updated workflow can correctly identify multiple microbes at the genus and often the species level for samples containing more than one microbe. We have also shown that the proposed workflow computes accurate statistical significances, i.e., E values for identified peptides and unified E values for identified microbes. Our updated analysis workflow MiCId, a freely available software for Microorganism Classification and Identification, is available for download at https://www.ncbi.nlm.nih.gov/CBBresearch/Yu/downloads.html . Graphical Abstract ᅟ.

  5. In situ, accurate, surface-enhanced Raman scattering detection of cancer cell nucleus with synchronous location by an alkyne-labeled biomolecular probe.

    Science.gov (United States)

    Zhang, Jing; Liang, Lijia; Guan, Xin; Deng, Rong; Qu, Huixin; Huang, Dianshuai; Xu, Shuping; Liang, Chongyang; Xu, Weiqing

    2018-01-01

    A surface-enhanced Raman scattering (SERS) method for in situ detection and analysis of the intranuclear biomolecular information of a cell has been developed based on a small, biocompatible, nuclear-targeting alkyne-tagged deoxyribonucleic acid (DNA) probe (5-ethynyl-2'-deoxyuridine, EDU) that can specially accumulate in the cell nucleus during DNA replications to precisely locate the nuclear region without disturbance in cell biological activities and functions. Since the specific alkyne group shows a Raman peak in the Raman-silent region of cells, it is an interior label to visualize the nuclear location synchronously in real time when measuring the SERS spectra of a cell. Because no fluorescent-labeled dyes were used for locating cell nuclei, this method is simple, nondestructive, non- photobleaching, and valuable for the in situ exploration of vital physiological processes with DNA participation in cell organelles. Graphical abstract A universal strategy was developed to accurately locate the nuclear region and obtain precise molecular information of cell nuclei by SERS.

  6. SpineAnalyzer™ is an accurate and precise method of vertebral fracture detection and classification on dual-energy lateral vertebral assessment scans

    International Nuclear Information System (INIS)

    Birch, C.; Knapp, K.; Hopkins, S.; Gallimore, S.; Rock, B.

    2015-01-01

    Osteoporotic fractures of the spine are associated with significant morbidity, are highly predictive of hip fractures, but frequently do not present clinically. When there is a low to moderate clinical suspicion of vertebral fracture, which would not justify acquisition of a radiograph, vertebral fracture assessment (VFA) using Dual-energy X-ray Absorptiometry (DXA) offers a low-dose opportunity for diagnosis. Different approaches to the classification of vertebral fractures have been documented. The aim of this study was to measure the precision and accuracy of SpineAnalyzer™, a quantitative morphometry software program. Lateral vertebral assessment images of 64 men were analysed using SpineAnalyzer™ and standard GE Lunar software. The images were also analysed by two expert readers using a semi-quantitative approach. Agreement between groups ranged from 95.99% to 98.60%. The intra-rater precision for the application of SpineAnalyzer™ to vertebrae was poor in the upper thoracic regions, but good elsewhere. SpineAnalyzer™ is a reproducible and accurate method for measuring vertebral height and quantifying vertebral fractures from VFA scans. - Highlights: • Vertebral fracture assessment (VFA) using Dual-energy X-ray Absorptiometry (DXA) offers a low-dose opportunity for diagnosis. • Agreement between VFA software (SpineAnalyzer™) and expert readers is high. • Intra-rater precision of SpineAnalyzer™ applied to upper thoracic vertebrae is poor, but good elsewhere. • SpineAnalyzer™ is reproducible and accurate for vertebral height measurement and fracture quantification from VFA scans

  7. Development of salt-tolerance interface for an high performance liquid chromatography/inductively coupled plasma mass spectrometry system and its application to accurate quantification of DNA samples.

    Science.gov (United States)

    Takasaki, Yuka; Sakagawa, Shinnosuke; Inagaki, Kazumi; Fujii, Shin-Ichiro; Sabarudin, Akhmad; Umemura, Tomonari; Haraguchi, Hiroki

    2012-02-03

    Accurate quantification of DNA is highly important in various fields. Determination of phosphorus by ICP-MS is one of the most effective methods for accurate quantification of DNA due to the fixed stoichiometry of phosphate to this molecule. In this paper, a smart and reliable method for accurate quantification of DNA fragments and oligodeoxythymidilic acids by hyphenated HPLC/ICP-MS equipped with a highly efficient interface device is presented. The interface was constructed of a home-made capillary-attached micronebulizer and temperature-controllable cyclonic spray chamber (IsoMist). As a separation column for DNA samples, home-made methacrylate-based weak anion-exchange monolith was employed. Some parameters, which include composition of mobile phase, gradient program, inner and outer diameters of capillary, temperature of spray chamber etc., were optimized to find the best performance for separation and accurate quantification of DNA samples. The proposed system could achieve many advantages, such as total consumption for small amount sample analysis, salt-tolerance for hyphenated analysis, high accuracy and precision for quantitative analysis. Using this proposed system, the samples of 20 bp DNA ladder (20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 300, 400, 500 base pairs) and oligodeoxythymidilic acids (dT(12-18)) were rapidly separated and accurately quantified. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. High on Crime Fiction and Detection

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2010-01-01

    how crime fiction activates strong salience (in some respects similar to the effect of dopamine-drugs like cocaine, Ritalin, and amphetamine) and discusses the role of social intelligence in crime fiction. It further contrasts the unempathic classical detector fictions with two subtypes of crime...... fiction that blend seeking with other emotions: the hardboiled crime fiction that blends detection with action and hot emotions like anger and bonding, and the moral crime fiction that strongly evokes moral disgust and contempt, often in conjunction with detectors that perform hard to fake signals...

  9. Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding.

    Science.gov (United States)

    Ashktorab, Hassan; Etaati, Firoozeh; Rezaeean, Farahnaz; Nouraie, Mehdi; Paydar, Mansour; Namin, Hassan Hassanzadeh; Sanderson, Andrew; Begum, Rehana; Alkhalloufi, Kawtar; Brim, Hassan; Laiyemo, Adeyinka O

    2016-07-28

    To study the accuracy of using high definition (HD) scope with narrow band imaging (NBI) vs standard white light colonoscope without NBI (ST), to predict the histology of the colon polyps, particularly those high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. Of participants in the study, 55 (37%) were male and median (interquartile range) of age was 56 (19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were scope (P = 0.7). The ST scope had a positive predictive value (PPV) and positive likelihood ratio (PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope (68%) compare to ST scope (53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp (HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar. Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology.

  10. Accurate measurement of junctional conductance between electrically coupled cells with dual whole-cell voltage-clamp under conditions of high series resistance.

    Science.gov (United States)

    Hartveit, Espen; Veruki, Margaret Lin

    2010-03-15

    Accurate measurement of the junctional conductance (G(j)) between electrically coupled cells can provide important information about the functional properties of coupling. With the development of tight-seal, whole-cell recording, it became possible to use dual, single-electrode voltage-clamp recording from pairs of small cells to measure G(j). Experiments that require reduced perturbation of the intracellular environment can be performed with high-resistance pipettes or the perforated-patch technique, but an accompanying increase in series resistance (R(s)) compromises voltage-clamp control and reduces the accuracy of G(j) measurements. Here, we present a detailed analysis of methodologies available for accurate determination of steady-state G(j) and related parameters under conditions of high R(s), using continuous or discontinuous single-electrode voltage-clamp (CSEVC or DSEVC) amplifiers to quantify the parameters of different equivalent electrical circuit model cells. Both types of amplifiers can provide accurate measurements of G(j), with errors less than 5% for a wide range of R(s) and G(j) values. However, CSEVC amplifiers need to be combined with R(s)-compensation or mathematical correction for the effects of nonzero R(s) and finite membrane resistance (R(m)). R(s)-compensation is difficult for higher values of R(s) and leads to instability that can damage the recorded cells. Mathematical correction for R(s) and R(m) yields highly accurate results, but depends on accurate estimates of R(s) throughout an experiment. DSEVC amplifiers display very accurate measurements over a larger range of R(s) values than CSEVC amplifiers and have the advantage that knowledge of R(s) is unnecessary, suggesting that they are preferable for long-duration experiments and/or recordings with high R(s). Copyright (c) 2009 Elsevier B.V. All rights reserved.

  11. Detecting Faults In High-Voltage Transformers

    Science.gov (United States)

    Blow, Raymond K.

    1988-01-01

    Simple fixture quickly shows whether high-voltage transformer has excessive voids in dielectric materials and whether high-voltage lead wires too close to transformer case. Fixture is "go/no-go" indicator; corona appears if transformer contains such faults. Nests in wire mesh supported by cap of clear epoxy. If transformer has defects, blue glow of corona appears in mesh and is seen through cap.

  12. The Field Assessment Stroke Triage for Emergency Destination (FAST-ED): a Simple and Accurate Pre-Hospital Scale to Detect Large Vessel Occlusion Strokes

    Science.gov (United States)

    Lima, Fabricio O.; Silva, Gisele S.; Furie, Karen L.; Frankel, Michael R.; Lev, Michael H.; Camargo, Érica CS; Haussen, Diogo C.; Singhal, Aneesh B.; Koroshetz, Walter J.; Smith, Wade S.; Nogueira, Raul G.

    2016-01-01

    Background and Purpose Patients with large vessel occlusion strokes (LVOS) may be better served by direct transfer to endovascular capable centers avoiding hazardous delays between primary and comprehensive stroke centers. However, accurate stroke field triage remains challenging. We aimed to develop a simple field scale to identify LVOS. Methods The FAST-ED scale was based on items of the NIHSS with higher predictive value for LVOS and tested in the STOPStroke cohort, in which patients underwent CT angiography within the first 24 hours of stroke onset. LVOS were defined by total occlusions involving the intracranial-ICA, MCA-M1, MCA-2, or basilar arteries. Patients with partial, bi-hemispheric, and/or anterior + posterior circulation occlusions were excluded. Receiver operating characteristic (ROC) curve, sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of FAST-ED were compared with the NIHSS, Rapid Arterial oCclusion Evaluation (RACE) scale and Cincinnati Prehospital Stroke Severity Scale (CPSSS). Results LVO was detected in 240 of the 727 qualifying patients (33%). FAST-ED had comparable accuracy to predict LVO to the NIHSS and higher accuracy than RACE and CPSS (area under the ROC curve: FAST-ED=0.81 as reference; NIHSS=0.80, p=0.28; RACE=0.77, p=0.02; and CPSS=0.75, p=0.002). A FAST-ED ≥4 had sensitivity of 0.60, specificity 0.89, PPV 0.72, and NPV 0.82 versus RACE ≥5 of 0.55, 0.87, 0.68, 0.79 and CPSS ≥2 of 0.56, 0.85, 0.65, 0.78, respectively. Conclusions FAST-ED is a simple scale that if successfully validated in the field may be used by medical emergency professionals to identify LVOS in the pre-hospital setting enabling rapid triage of patients. PMID:27364531

  13. The detection of the methylated Wif-1 gene is more accurate than a fecal occult blood test for colorectal cancer screening

    KAUST Repository

    Amiot, Aurelien; Mansour, Hicham; Baumgaertner, Isabelle; Delchier, Jean-Charles; Tournigand, Christophe; Furet, Jean-Pierre; Carrau, Jean-Pierre; Canoui-Poitrine, Florence; Sobhani, Iradj

    2014-01-01

    Background: The clinical benefit of guaiac fecal occult blood tests (FOBT) is now well established for colorectal cancer screening. Growing evidence has demonstrated that epigenetic modifications and fecal microbiota changes, also known as dysbiosis, are associated with CRC pathogenesis and might be used as surrogate markers of CRC. Patients and Methods: We performed a cross-sectional study that included all consecutive subjects that were referred (from 2003 to 2007) for screening colonoscopies. Prior to colonoscopy, effluents (fresh stools, sera-S and urine-U) were harvested and FOBTs performed. Methylation levels were measured in stools, S and U for 3 genes (Wif1, ALX-4, and Vimentin) selected from a panel of 63 genes; Kras mutations and seven dominant and subdominant bacterial populations in stools were quantified. Calibration was assessed with the Hosmer-Lemeshow chi-square, and discrimination was determined by calculating the C-statistic (Area Under Curve) and Net Reclassification Improvement index. Results: There were 247 individuals (mean age 60.8±12.4 years, 52% of males) in the study group, and 90 (36%) of these individuals were patients with advanced polyps or invasive adenocarcinomas. A multivariate model adjusted for age and FOBT led to a C-statistic of 0.83 [0.77-0.88]. After supplementary sequential (one-by-one) adjustment, Wif-1 methylation (S or U) and fecal microbiota dysbiosis led to increases of the C-statistic to 0.90 [0.84-0.94] (p = 0.02) and 0.81 [0.74-0.86] (p = 0.49), respectively. When adjusted jointly for FOBT and Wif-1 methylation or fecal microbiota dysbiosis, the increase of the C-statistic was even more significant (0.91 and 0.85, p<0.001 and p = 0.10, respectively). Conclusion: The detection of methylated Wif-1 in either S or U has a higher performance accuracy compared to guaiac FOBT for advanced colorectal neoplasia screening. Conversely, fecal microbiota dysbiosis detection was not more accurate. Blood and urine testing could be

  14. The detection of the methylated Wif-1 gene is more accurate than a fecal occult blood test for colorectal cancer screening

    KAUST Repository

    Amiot, Aurelien

    2014-07-15

    Background: The clinical benefit of guaiac fecal occult blood tests (FOBT) is now well established for colorectal cancer screening. Growing evidence has demonstrated that epigenetic modifications and fecal microbiota changes, also known as dysbiosis, are associated with CRC pathogenesis and might be used as surrogate markers of CRC. Patients and Methods: We performed a cross-sectional study that included all consecutive subjects that were referred (from 2003 to 2007) for screening colonoscopies. Prior to colonoscopy, effluents (fresh stools, sera-S and urine-U) were harvested and FOBTs performed. Methylation levels were measured in stools, S and U for 3 genes (Wif1, ALX-4, and Vimentin) selected from a panel of 63 genes; Kras mutations and seven dominant and subdominant bacterial populations in stools were quantified. Calibration was assessed with the Hosmer-Lemeshow chi-square, and discrimination was determined by calculating the C-statistic (Area Under Curve) and Net Reclassification Improvement index. Results: There were 247 individuals (mean age 60.8±12.4 years, 52% of males) in the study group, and 90 (36%) of these individuals were patients with advanced polyps or invasive adenocarcinomas. A multivariate model adjusted for age and FOBT led to a C-statistic of 0.83 [0.77-0.88]. After supplementary sequential (one-by-one) adjustment, Wif-1 methylation (S or U) and fecal microbiota dysbiosis led to increases of the C-statistic to 0.90 [0.84-0.94] (p = 0.02) and 0.81 [0.74-0.86] (p = 0.49), respectively. When adjusted jointly for FOBT and Wif-1 methylation or fecal microbiota dysbiosis, the increase of the C-statistic was even more significant (0.91 and 0.85, p<0.001 and p = 0.10, respectively). Conclusion: The detection of methylated Wif-1 in either S or U has a higher performance accuracy compared to guaiac FOBT for advanced colorectal neoplasia screening. Conversely, fecal microbiota dysbiosis detection was not more accurate. Blood and urine testing could be

  15. The detection of the methylated Wif-1 gene is more accurate than a fecal occult blood test for colorectal cancer screening.

    Directory of Open Access Journals (Sweden)

    Aurelien Amiot

    Full Text Available The clinical benefit of guaiac fecal occult blood tests (FOBT is now well established for colorectal cancer screening. Growing evidence has demonstrated that epigenetic modifications and fecal microbiota changes, also known as dysbiosis, are associated with CRC pathogenesis and might be used as surrogate markers of CRC.We performed a cross-sectional study that included all consecutive subjects that were referred (from 2003 to 2007 for screening colonoscopies. Prior to colonoscopy, effluents (fresh stools, sera-S and urine-U were harvested and FOBTs performed. Methylation levels were measured in stools, S and U for 3 genes (Wif1, ALX-4, and Vimentin selected from a panel of 63 genes; Kras mutations and seven dominant and subdominant bacterial populations in stools were quantified. Calibration was assessed with the Hosmer-Lemeshow chi-square, and discrimination was determined by calculating the C-statistic (Area Under Curve and Net Reclassification Improvement index.There were 247 individuals (mean age 60.8±12.4 years, 52% of males in the study group, and 90 (36% of these individuals were patients with advanced polyps or invasive adenocarcinomas. A multivariate model adjusted for age and FOBT led to a C-statistic of 0.83 [0.77-0.88]. After supplementary sequential (one-by-one adjustment, Wif-1 methylation (S or U and fecal microbiota dysbiosis led to increases of the C-statistic to 0.90 [0.84-0.94] (p = 0.02 and 0.81 [0.74-0.86] (p = 0.49, respectively. When adjusted jointly for FOBT and Wif-1 methylation or fecal microbiota dysbiosis, the increase of the C-statistic was even more significant (0.91 and 0.85, p<0.001 and p = 0.10, respectively.The detection of methylated Wif-1 in either S or U has a higher performance accuracy compared to guaiac FOBT for advanced colorectal neoplasia screening. Conversely, fecal microbiota dysbiosis detection was not more accurate. Blood and urine testing could be used in those individuals reluctant to

  16. Accurate mass measurements of very short-lived nuclei. Prerequisites for high-accuracy investigations of superallowed β-decays

    International Nuclear Information System (INIS)

    Herfurth, F.; Kellerbauer, A.; Sauvan, E.; Ames, F.; Engels, O.; Audi, G.; Lunney, D.; Beck, D.; Blaum, K.; Kluge, H.J.; Scheidenberger, C.; Sikler, G.; Weber, C.; Bollen, G.; Schwarz, S.; Moore, R.B.; Oinonen, M.

    2002-01-01

    Mass measurements of 34 Ar, 73-78 Kr, and 74,76 Rb were performed with the Penning-trap mass spectrometer ISOLTRAP. Very accurate Q EC -values are needed for the investigations of the Ft-value of 0 + → 0 + nuclear β-decays used to test the standard model predictions for weak interactions. The necessary accuracy on the Q EC -value requires the mass of mother and daughter nuclei to be measured with δm/m ≤ 3 . 10 -8 . For most of the measured nuclides presented here this has been reached. The 34 Ar mass has been measured with a relative accuracy of 1.1 .10 -8 . The Q EC -value of the 34 Ar 0 + → 0 + decay can now be determined with an uncertainty of about 0.01%. Furthermore, 74 Rb is the shortest-lived nuclide ever investigated in a Penning trap. (orig.)

  17. Accurate dipole moment curve and non-adiabatic effects on the high resolution spectroscopic properties of the LiH molecule

    Science.gov (United States)

    Diniz, Leonardo G.; Kirnosov, Nikita; Alijah, Alexander; Mohallem, José R.; Adamowicz, Ludwik

    2016-04-01

    A very accurate dipole moment curve (DMC) for the ground X1Σ+ electronic state of the 7LiH molecule is reported. It is calculated with the use of all-particle explicitly correlated Gaussian functions with shifted centers. The DMC - the most accurate to our knowledge - and the corresponding highly accurate potential energy curve are used to calculate the transition energies, the transition dipole moments, and the Einstein coefficients for the rovibrational transitions with ΔJ = - 1 and Δv ⩽ 5 . The importance of the non-adiabatic effects in determining these properties is evaluated using the model of a vibrational R-dependent effective reduced mass in the rovibrational calculations introduced earlier (Diniz et al., 2015). The results of the present calculations are used to assess the quality of the two complete linelists of 7LiH available in the literature.

  18. Accurate prediction of retention in hydrophilic interaction chromatography by back calculation of high pressure liquid chromatography gradient profiles.

    Science.gov (United States)

    Wang, Nu; Boswell, Paul G

    2017-10-20

    Gradient retention times are difficult to project from the underlying retention factor (k) vs. solvent composition (φ) relationships. A major reason for this difficulty is that gradients produced by HPLC pumps are imperfect - gradient delay, gradient dispersion, and solvent mis-proportioning are all difficult to account for in calculations. However, we recently showed that a gradient "back-calculation" methodology can measure these imperfections and take them into account. In RPLC, when the back-calculation methodology was used, error in projected gradient retention times is as low as could be expected based on repeatability in the k vs. φ relationships. HILIC, however, presents a new challenge: the selectivity of HILIC columns drift strongly over time. Retention is repeatable in short time, but selectivity frequently drifts over the course of weeks. In this study, we set out to understand if the issue of selectivity drift can be avoid by doing our experiments quickly, and if there any other factors that make it difficult to predict gradient retention times from isocratic k vs. φ relationships when gradient imperfections are taken into account with the back-calculation methodology. While in past reports, the accuracy of retention projections was >5%, the back-calculation methodology brought our error down to ∼1%. This result was 6-43 times more accurate than projections made using ideal gradients and 3-5 times more accurate than the same retention projections made using offset gradients (i.e., gradients that only took gradient delay into account). Still, the error remained higher in our HILIC projections than in RPLC. Based on the shape of the back-calculated gradients, we suspect the higher error is a result of prominent gradient distortion caused by strong, preferential water uptake from the mobile phase into the stationary phase during the gradient - a factor our model did not properly take into account. It appears that, at least with the stationary phase

  19. Scalable implementations of accurate excited-state coupled cluster theories: application of high-level methods to porphyrin based systems

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, Karol; Krishnamoorthy, Sriram; Olson, Ryan M.; Tipparaju, Vinod; Apra, Edoardo

    2011-11-30

    The development of reliable tools for excited-state simulations is emerging as an extremely powerful computational chemistry tool for understanding complex processes in the broad class of light harvesting systems and optoelectronic devices. Over the last years we have been developing equation of motion coupled cluster (EOMCC) methods capable of tackling these problems. In this paper we discuss the parallel performance of EOMCC codes which provide accurate description of the excited-state correlation effects. Two aspects are discuss in details: (1) a new algorithm for the iterative EOMCC methods based on the novel task scheduling algorithms, and (2) parallel algorithms for the non-iterative methods describing the effect of triply excited configurations. We demonstrate that the most computationally intensive non-iterative part can take advantage of 210,000 cores of the Cray XT5 system at OLCF. In particular, we demonstrate the importance of non-iterative many-body methods for achieving experimental level of accuracy for several porphyrin-based system.

  20. Cascade Boosting-Based Object Detection from High-Level Description to Hardware Implementation

    Directory of Open Access Journals (Sweden)

    K. Khattab

    2009-01-01

    Full Text Available Object detection forms the first step of a larger setup for a wide variety of computer vision applications. The focus of this paper is the implementation of a real-time embedded object detection system while relying on high-level description language such as SystemC. Boosting-based object detection algorithms are considered as the fastest accurate object detection algorithms today. However, the implementation of a real time solution for such algorithms is still a challenge. A new parallel implementation, which exploits the parallelism and the pipelining in these algorithms, is proposed. We show that using a SystemC description model paired with a mainstream automatic synthesis tool can lead to an efficient embedded implementation. We also display some of the tradeoffs and considerations, for this implementation to be effective. This implementation proves capable of achieving 42 fps for 320×240 images as well as bringing regularity in time consuming.

  1. Development of a neutron detector with high detection efficiency and high spatial resolution and its applications to reactor physics experiments

    International Nuclear Information System (INIS)

    Tojo, Takao

    1979-09-01

    For detection of thermal neutrons in multiplying systems, a scintillator mixture of ZnS(Ag), 6 LiF and polyethylene was prepared, and its characteristics were shown. A sintillation detector using the mixture and a long acrylic-resin light guide was developed for measuring thermal neutrons in an U-H 2 O subcritical assembly(JAERISA). The detector was applied in the following reactor physics measurements with JAERISA: (1) cadmium ratio, (2) infinite multiplication factor, (3) material buckling, and (4) prompt neutron lifetime by pulsed neutron method. These experiments revealed that neutrons in the assembly are successfully detected by the detector owing to its outstanding characteristics of gamma-ray insensitivity, high detection efficiency and high spatial resolution. In the process of activity measurement of a foil activation detector with a GM counter, it was shown that accurate counting loss correction are difficult by usual method, because of the appreciable resolving time dependence on counting rates. In accurate correction, a new method was introduced for precise measurement of the resolving time; the dependence was made clear. A new correction method was developed, which enables direct reading of the corrected counting rates, even at high counting rates. (author)

  2. Detection and estimation research of high-speed railway catenary

    CERN Document Server

    Liu, Zhigang

    2017-01-01

    This book describes the wave characteristics of contact lines taking wind into consideration and discusses new methods for detecting catenary geometry, pantograph slide fault, and catenary support system faults. It also introduces wire-irregularity detection methods for catenary estimation, and discusses modern spectrum estimation tools for catenary. It is organized in three parts: the first discusses statistical characteristics of pantograph-catenary data, such as stationarity, periodicity, correlation, high-order statistical properties and wave characteristics of contact lines, which are the basis of pantograph-catenary relationship analysis. The second part includes geometry parameter detection and support-system fault detection in catenary, as well as slide-fault detection in pantographs, and presents some new detection algorithms and plans. The final part addresses catenary estimation, including detection of contact-line wire irregularities and estimation of catenary based on spectrum, and presents detec...

  3. A highly accurate predictive-adaptive method for lithium-ion battery remaining discharge energy prediction in electric vehicle applications

    International Nuclear Information System (INIS)

    Liu, Guangming; Ouyang, Minggao; Lu, Languang; Li, Jianqiu; Hua, Jianfeng

    2015-01-01

    importance of an accurate E RDE method in real-world applications

  4. FMR1 CGG repeat expansion mutation detection and linked haplotype analysis for reliable and accurate preimplantation genetic diagnosis of fragile X syndrome.

    Science.gov (United States)

    Rajan-Babu, Indhu-Shree; Lian, Mulias; Cheah, Felicia S H; Chen, Min; Tan, Arnold S C; Prasath, Ethiraj B; Loh, Seong Feei; Chong, Samuel S

    2017-07-19

    Fragile X mental retardation 1 (FMR1) full-mutation expansion causes fragile X syndrome. Trans-generational fragile X syndrome transmission can be avoided by preimplantation genetic diagnosis (PGD). We describe a robust PGD strategy that can be applied to virtually any couple at risk of transmitting fragile X syndrome. This novel strategy utilises whole-genome amplification, followed by triplet-primed polymerase chain reaction (TP-PCR) for robust detection of expanded FMR1 alleles, in parallel with linked multi-marker haplotype analysis of 13 highly polymorphic microsatellite markers located within 1 Mb of the FMR1 CGG repeat, and the AMELX/Y dimorphism for gender identification. The assay was optimised and validated on single lymphoblasts isolated from fragile X reference cell lines, and applied to a simulated PGD case and a clinical in vitro fertilisation (IVF)-PGD case. In the simulated PGD case, definitive diagnosis of the expected results was achieved for all 'embryos'. In the clinical IVF-PGD case, delivery of a healthy baby girl was achieved after transfer of an expansion-negative blastocyst. FMR1 TP-PCR reliably detects presence of expansion mutations and obviates reliance on informative normal alleles for determining expansion status in female embryos. Together with multi-marker haplotyping and gender determination, misdiagnosis and diagnostic ambiguity due to allele dropout is minimised, and couple-specific assay customisation can be avoided.

  5. High Resolution Viscosity Measurement by Thermal Noise Detection

    Directory of Open Access Journals (Sweden)

    Felipe Aguilar Sandoval

    2015-11-01

    Full Text Available An interferometric method is implemented in order to accurately assess the thermal fluctuations of a micro-cantilever sensor in liquid environments. The power spectrum density (PSD of thermal fluctuations together with Sader’s model of the cantilever allow for the indirect measurement of the liquid viscosity with good accuracy. The good quality of the deflection signal and the characteristic low noise of the instrument allow for the detection and corrections of drawbacks due to both the cantilever shape irregularities and the uncertainties on the position of the laser spot at the fluctuating end of the cantilever. Variation of viscosity below 0.03 mPa·s was detected with the alternative to achieve measurements with a volume as low as 50 µL.

  6. An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers.

    Science.gov (United States)

    Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

    2013-07-01

    Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Based on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class.

  7. An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers

    International Nuclear Information System (INIS)

    Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

    2013-01-01

    Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Based on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class

  8. Fault Analysis and Detection in Microgrids with High PV Penetration

    Energy Technology Data Exchange (ETDEWEB)

    El Khatib, Mohamed [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hernandez Alvidrez, Javier [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ellis, Abraham [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    In this report we focus on analyzing current-controlled PV inverters behaviour under faults in order to develop fault detection schemes for microgrids with high PV penetration. Inverter model suitable for steady state fault studies is presented and the impact of PV inverters on two protection elements is analyzed. The studied protection elements are superimposed quantities based directional element and negative sequence directional element. Additionally, several non-overcurrent fault detection schemes are discussed in this report for microgrids with high PV penetration. A detailed time-domain simulation study is presented to assess the performance of the presented fault detection schemes under different microgrid modes of operation.

  9. Detection of Free Polyamines in Plants Subjected to Abiotic Stresses by High-Performance Liquid Chromatography (HPLC).

    Science.gov (United States)

    Gong, Xiaoqing; Liu, Ji-Hong

    2017-01-01

    High-performance liquid chromatography (HPLC) is a sensitive, rapid, and accurate technique to detect and characterize various metabolites from plants. The metabolites are extracted with different solvents and eluted with appropriate mobile phases in a designed HPLC program. Polyamines are known to accumulate under abiotic stress conditions in various plant species and thought to provide protection against oxidative stress by scavenging reactive oxygen species. Here, we describe a common method to detect the free polyamines in plant tissues both qualitatively and quantitatively.

  10. Use of a Recursive-Rule eXtraction algorithm with J48graft to achieve highly accurate and concise rule extraction from a large breast cancer dataset

    Directory of Open Access Journals (Sweden)

    Yoichi Hayashi

    Full Text Available To assist physicians in the diagnosis of breast cancer and thereby improve survival, a highly accurate computer-aided diagnostic system is necessary. Although various machine learning and data mining approaches have been devised to increase diagnostic accuracy, most current methods are inadequate. The recently developed Recursive-Rule eXtraction (Re-RX algorithm provides a hierarchical, recursive consideration of discrete variables prior to analysis of continuous data, and can generate classification rules that have been trained on the basis of both discrete and continuous attributes. The objective of this study was to extract highly accurate, concise, and interpretable classification rules for diagnosis using the Re-RX algorithm with J48graft, a class for generating a grafted C4.5 decision tree. We used the Wisconsin Breast Cancer Dataset (WBCD. Nine research groups provided 10 kinds of highly accurate concrete classification rules for the WBCD. We compared the accuracy and characteristics of the rule set for the WBCD generated using the Re-RX algorithm with J48graft with five rule sets obtained using 10-fold cross validation (CV. We trained the WBCD using the Re-RX algorithm with J48graft and the average classification accuracies of 10 runs of 10-fold CV for the training and test datasets, the number of extracted rules, and the average number of antecedents for the WBCD. Compared with other rule extraction algorithms, the Re-RX algorithm with J48graft resulted in a lower average number of rules for diagnosing breast cancer, which is a substantial advantage. It also provided the lowest average number of antecedents per rule. These features are expected to greatly aid physicians in making accurate and concise diagnoses for patients with breast cancer. Keywords: Breast cancer diagnosis, Rule extraction, Re-RX algorithm, J48graft, C4.5

  11. Label-Driven Learning Framework: Towards More Accurate Bayesian Network Classifiers through Discrimination of High-Confidence Labels

    Directory of Open Access Journals (Sweden)

    Yi Sun

    2017-12-01

    Full Text Available Bayesian network classifiers (BNCs have demonstrated competitive classification accuracy in a variety of real-world applications. However, it is error-prone for BNCs to discriminate among high-confidence labels. To address this issue, we propose the label-driven learning framework, which incorporates instance-based learning and ensemble learning. For each testing instance, high-confidence labels are first selected by a generalist classifier, e.g., the tree-augmented naive Bayes (TAN classifier. Then, by focusing on these labels, conditional mutual information is redefined to more precisely measure mutual dependence between attributes, thus leading to a refined generalist with a more reasonable network structure. To enable finer discrimination, an expert classifier is tailored for each high-confidence label. Finally, the predictions of the refined generalist and the experts are aggregated. We extend TAN to LTAN (Label-driven TAN by applying the proposed framework. Extensive experimental results demonstrate that LTAN delivers superior classification accuracy to not only several state-of-the-art single-structure BNCs but also some established ensemble BNCs at the expense of reasonable computation overhead.

  12. ExSTA: External Standard Addition Method for Accurate High-Throughput Quantitation in Targeted Proteomics Experiments.

    Science.gov (United States)

    Mohammed, Yassene; Pan, Jingxi; Zhang, Suping; Han, Jun; Borchers, Christoph H

    2018-03-01

    Targeted proteomics using MRM with stable-isotope-labeled internal-standard (SIS) peptides is the current method of choice for protein quantitation in complex biological matrices. Better quantitation can be achieved with the internal standard-addition method, where successive increments of synthesized natural form (NAT) of the endogenous analyte are added to each sample, a response curve is generated, and the endogenous concentration is determined at the x-intercept. Internal NAT-addition, however, requires multiple analyses of each sample, resulting in increased sample consumption and analysis time. To compare the following three methods, an MRM assay for 34 high-to-moderate abundance human plasma proteins is used: classical internal SIS-addition, internal NAT-addition, and external NAT-addition-generated in buffer using NAT and SIS peptides. Using endogenous-free chicken plasma, the accuracy is also evaluated. The internal NAT-addition outperforms the other two in precision and accuracy. However, the curves derived by internal vs. external NAT-addition differ by only ≈3.8% in slope, providing comparable accuracies and precision with good CV values. While the internal NAT-addition method may be "ideal", this new external NAT-addition can be used to determine the concentration of high-to-moderate abundance endogenous plasma proteins, providing a robust and cost-effective alternative for clinical analyses or other high-throughput applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. A high-throughput multiplex method adapted for GMO detection.

    Science.gov (United States)

    Chaouachi, Maher; Chupeau, Gaëlle; Berard, Aurélie; McKhann, Heather; Romaniuk, Marcel; Giancola, Sandra; Laval, Valérie; Bertheau, Yves; Brunel, Dominique

    2008-12-24

    A high-throughput multiplex assay for the detection of genetically modified organisms (GMO) was developed on the basis of the existing SNPlex method designed for SNP genotyping. This SNPlex assay allows the simultaneous detection of up to 48 short DNA sequences (approximately 70 bp; "signature sequences") from taxa endogenous reference genes, from GMO constructions, screening targets, construct-specific, and event-specific targets, and finally from donor organisms. This assay avoids certain shortcomings of multiplex PCR-based methods already in widespread use for GMO detection. The assay demonstrated high specificity and sensitivity. The results suggest that this assay is reliable, flexible, and cost- and time-effective for high-throughput GMO detection.

  14. Accurate and precise 40Ar/39Ar dating by high-resolution, multi-collection, mass spectrometry

    DEFF Research Database (Denmark)

    Storey, Michael; Rivera, Tiffany; Flude, Stephanie

    New generation, high resolution, multi-collector noble gas mass spectrometers equipped with ion-counting electron multipliers provide opportunities for improved accuracy and precision in 40Ar/39Ar dating. Here we report analytical protocols and age cross-calibration studies using a NU-Instruments......New generation, high resolution, multi-collector noble gas mass spectrometers equipped with ion-counting electron multipliers provide opportunities for improved accuracy and precision in 40Ar/39Ar dating. Here we report analytical protocols and age cross-calibration studies using a NU......-Instruments multi-collector Noblesse noble gas mass spectrometer configured with a faraday detector and three ion-counting electron multipliers. The instrument has the capability to measure several noble gas isotopes simultaneously and to change measurement configurations instantaneously by the use of QUAD lenses...... (zoom optics). The Noblesse offer several advantages over previous generation noble gas mass spectrometers and is particularly suited for single crystal 40Ar/39Ar dating because of: (i) improved source sensitivity (ii) ion-counting electron multipliers, which have much lower signal to noise ratios than...

  15. Detecting Android Malwares with High-Efficient Hybrid Analyzing Methods

    Directory of Open Access Journals (Sweden)

    Yu Liu

    2018-01-01

    Full Text Available In order to tackle the security issues caused by malwares of Android OS, we proposed a high-efficient hybrid-detecting scheme for Android malwares. Our scheme employed different analyzing methods (static and dynamic methods to construct a flexible detecting scheme. In this paper, we proposed some detecting techniques such as Com+ feature based on traditional Permission and API call features to improve the performance of static detection. The collapsing issue of traditional function call graph-based malware detection was also avoided, as we adopted feature selection and clustering method to unify function call graph features of various dimensions into same dimension. In order to verify the performance of our scheme, we built an open-access malware dataset in our experiments. The experimental results showed that the suggested scheme achieved high malware-detecting accuracy, and the scheme could be used to establish Android malware-detecting cloud services, which can automatically adopt high-efficiency analyzing methods according to the properties of the Android applications.

  16. Encoding negative events under stress: high subjective arousal is related to accurate emotional memory despite misinformation exposure.

    Science.gov (United States)

    Hoscheidt, Siobhan M; LaBar, Kevin S; Ryan, Lee; Jacobs, W Jake; Nadel, Lynn

    2014-07-01

    Stress at encoding affects memory processes, typically enhancing, or preserving, memory for emotional information. These effects have interesting implications for eyewitness accounts, which in real-world contexts typically involve encoding an aversive event under stressful conditions followed by potential exposure to misinformation. The present study investigated memory for a negative event encoded under stress and subsequent misinformation endorsement. Healthy young adults participated in a between-groups design with three experimental sessions conducted 48 h apart. Session one consisted of a psychosocial stress induction (or control task) followed by incidental encoding of a negative slideshow. During session two, participants were asked questions about the slideshow, during which a random subgroup was exposed to misinformation. Memory for the slideshow was tested during the third session. Assessment of memory accuracy across stress and no-stress groups revealed that stress induced just prior to encoding led to significantly better memory for the slideshow overall. The classic misinformation effect was also observed - participants exposed to misinformation were significantly more likely to endorse false information during memory testing. In the stress group, however, memory accuracy and misinformation effects were moderated by arousal experienced during encoding of the negative event. Misinformed-stress group participants who reported that the negative slideshow elicited high arousal during encoding were less likely to endorse misinformation for the most aversive phase of the story. Furthermore, these individuals showed better memory for components of the aversive slideshow phase that had been directly misinformed. Results from the current study provide evidence that stress and high subjective arousal elicited by a negative event act concomitantly during encoding to enhance emotional memory such that the most aversive aspects of the event are well remembered and

  17. An accurate calibration method for high pressure vibrating tube densimeters in the density interval (700 to 1600) kg . m-3

    International Nuclear Information System (INIS)

    Sanmamed, Yolanda A.; Dopazo-Paz, Ana; Gonzalez-Salgado, Diego; Troncoso, Jacobo; Romani, Luis

    2009-01-01

    A calibration procedure of vibrating tube densimeters for density measurement of liquids in the intervals (700 to 1600) kg . m -3 , (283.15 to 323.15) K, and (0.1 to 60) MPa is presented. It is based on the modelization of the vibrating tube as a thick-tube clamped at one end (cantilever) whose stress and thermal behaviour follows the ideas proposed in the Forced Path Mechanical Calibration model (FPMC). Model parameters are determined using two calibration fluids with densities certified at atmospheric pressure (dodecane and tetracholoroethylene) and a third one with densities known as a function of pressure (water). It is applied to the Anton Paar 512P densimeter, obtaining density measurements with an expanded uncertainty less than 0.2 kg . m -3 in the working intervals. This accuracy comes from the combination of several factors: densimeter behaves linearly in the working density interval, densities of both calibration fluids cover that interval and they have a very low uncertainty, and the mechanical behaviour of the tube is well characterized by the considered model. The main application of this method is the precise measurement of high density fluids for which most of the calibration procedures are inaccurate.

  18. Voltage spike detection in high field superconducting accelerator magnets

    Energy Technology Data Exchange (ETDEWEB)

    Orris, D.F.; Carcagno, R.; Feher, S.; Makulski, A.; Pischalnikov, Y.M.; /Fermilab

    2004-12-01

    A measurement system for the detection of small magnetic flux changes in superconducting magnets, which are due to either mechanical motion of the conductor or flux jump, has been developed at Fermilab. These flux changes are detected as small amplitude, short duration voltage spikes, which are {approx}15mV in magnitude and lasts for {approx}30 {micro}sec. The detection system combines an analog circuit for the signal conditioning of two coil segments and a fast data acquisition system for digitizing the results, performing threshold detection, and storing the resultant data. The design of the spike detection system along with the modeling results and noise analysis will be presented. Data from tests of high field Nb{sub 3}Sn magnets at currents up to {approx}20KA will also be shown.

  19. Voltage spike detection in high field superconducting accelerator magnets

    International Nuclear Information System (INIS)

    Orris, D.F.; Carcagno, R.; Feher, S.; Makulski, A.; Pischalnikov, Y.M.

    2004-01-01

    A measurement system for the detection of small magnetic flux changes in superconducting magnets, which are due to either mechanical motion of the conductor or flux jump, has been developed at Fermilab. These flux changes are detected as small amplitude, short duration voltage spikes, which are ∼15mV in magnitude and lasts for ∼30(micro)sec. The detection system combines an analog circuit for the signal conditioning of two coil segments and a fast data acquisition system for digitizing the results, performing threshold detection, and storing the resultant data. The design of the spike detection system along with the modeling results and noise analysis will be presented. Data from tests of high field Nb3Sn magnets at currents up to ∼20KA will also be shown

  20. Bayesian Peptide Peak Detection for High Resolution TOF Mass Spectrometry.

    Science.gov (United States)

    Zhang, Jianqiu; Zhou, Xiaobo; Wang, Honghui; Suffredini, Anthony; Zhang, Lin; Huang, Yufei; Wong, Stephen

    2010-11-01

    In this paper, we address the issue of peptide ion peak detection for high resolution time-of-flight (TOF) mass spectrometry (MS) data. A novel Bayesian peptide ion peak detection method is proposed for TOF data with resolution of 10 000-15 000 full width at half-maximum (FWHW). MS spectra exhibit distinct characteristics at this resolution, which are captured in a novel parametric model. Based on the proposed parametric model, a Bayesian peak detection algorithm based on Markov chain Monte Carlo (MCMC) sampling is developed. The proposed algorithm is tested on both simulated and real datasets. The results show a significant improvement in detection performance over a commonly employed method. The results also agree with expert's visual inspection. Moreover, better detection consistency is achieved across MS datasets from patients with identical pathological condition.

  1. Rapid detection and identification of four major Schistosoma species by high-resolution melt (HRM) analysis.

    Science.gov (United States)

    Li, Juan; Zhao, Guang-Hui; Lin, RuiQing; Blair, David; Sugiyama, Hiromu; Zhu, Xing-Quan

    2015-11-01

    Schistosomiasis, caused by blood flukes belonging to several species of the genus Schistosoma, is a serious and widespread parasitic disease. Accurate and rapid differentiation of these etiological agents of animal and human schistosomiasis to species level can be difficult. We report a real-time PCR assay coupled with a high-resolution melt (HRM) assay targeting a portion of the nuclear 18S rDNA to detect, identify, and distinguish between four major blood fluke species (Schistosoma japonicum, Schistosoma mansoni, Schistosoma haematobium, and Schistosoma mekongi). Using this system, the Schistosoma spp. was accurately identified and could also be distinguished from all other trematode species with which they were compared. As little as 10(-5) ng genomic DNA from a Schistosoma sp. could be detected. This process is inexpensive, easy, and can be completed within 3 h. Examination of 21 representative Schistosoma samples from 15 geographical localities in seven endemic countries validated the value of the HRM detection assay and proved its reliability. The melting curves were characterized by peaks of 83.65 °C for S. japonicum and S. mekongi, 85.65 °C for S. mansoni, and 85.85 °C for S. haematobium. The present study developed a real-time PCR coupled with HRM analysis assay for detection and differential identification of S. mansoni, S. haematobium, S. japonicum, and S. mekongi. This method is rapid, sensitive, and inexpensive. It has important implications for epidemiological studies of Schistosoma.

  2. Albuminuria and neck circumference are determinate factors of successful accurate estimation of glomerular filtration rate in high cardiovascular risk patients.

    Directory of Open Access Journals (Sweden)

    Po-Jen Hsiao

    Full Text Available Estimated glomerular filtration rate (eGFR is used for diagnosis of chronic kidney disease (CKD. The eGFR models based on serum creatinine or cystatin C are used more in clinical practice. Albuminuria and neck circumference are associated with CKD and may have correlations with eGFR.We explored the correlations and modelling formulates among various indicators such as serum creatinine, cystatin C, albuminuria, and neck circumference for eGFR.Cross-sectional study.We reviewed the records of patients with high cardiovascular risk from 2010 to 2011 in Taiwan. 24-hour urine creatinine clearance was used as the standard. We utilized a decision tree to select for variables and adopted a stepwise regression method to generate five models. Model 1 was based on only serum creatinine and was adjusted for age and gender. Model 2 added serum cystatin C, models 3 and 4 added albuminuria and neck circumference, respectively. Model 5 simultaneously added both albuminuria and neck circumference.Total 177 patients were recruited in this study. In model 1, the bias was 2.01 and its precision was 14.04. In model 2, the bias was reduced to 1.86 with a precision of 13.48. The bias of model 3 was 1.49 with a precision of 12.89, and the bias for model 4 was 1.74 with a precision of 12.97. In model 5, the bias could be lower to 1.40 with a precision of 12.53.In this study, the predicting ability of eGFR was improved after the addition of serum cystatin C compared to serum creatinine alone. The bias was more significantly reduced by the calculation of albuminuria. Furthermore, the model generated by combined albuminuria and neck circumference could provide the best eGFR predictions among these five eGFR models. Neck circumference can be investigated potentially in the further studies.

  3. Highly accurate nuclear and electronic stopping cross sections derived using Monte Carlo simulations to reproduce measured range data

    Science.gov (United States)

    Wittmaack, Klaus; Mutzke, Andreas

    2017-03-01

    We have examined and confirmed the previously unexplored concept of using Monte Carlo calculations in combination with measured projected ranges of ions implanted in solids to derive a quantitative description of nuclear interaction and electronic stopping. The study involved 98 ranges of 11B in Si between 1 keV and 8 MeV, contained in 12 sets of 10 different groups. Systematic errors by up to ±8% were removed to establish a refined data base with 93 ranges featuring only statistical uncertainties (±1.8%). The Monte Carlo calculations could be set up to reproduce the refined ranges with a mean ratio 1.002 ± 1.7%. The input parameters required for this very high level of agreement are as follows. Nuclear interaction is best described by the Kr-C potential, but in obligatory combination with the Lindhard-Scharff (LS) screening length. Up to 300 keV, the electronic stopping cross section is proportional to the projectile velocity, Se = kSe,LS, with k = 1.46 ± 0.01. At higher energies, Se falls progressively short of kSe,LS. Around the Bragg peak, i.e., between 0.8 and 10 MeV, Se is modeled by an adjustable function serving to tailor the peak shape properly. Calculated and measured isotope effects for ranges of 10B and 11B in Si agree within the experimental uncertainty (±0.25%). The range-based Se,R(E) reported here predicts the scarce experimental data derived from the energy loss in projectile transmission through thin Si foils to within 2% or better. By contrast, Se(E) data of available stopping power tables exhibit deviations from Se,R(E) between -40% and +14%.

  4. An improved energy-range relationship for high-energy electron beams based on multiple accurate experimental and Monte Carlo data sets

    International Nuclear Information System (INIS)

    Sorcini, B.B.; Andreo, P.; Hyoedynmaa, S.; Brahme, A.; Bielajew, A.F.

    1995-01-01

    A theoretically based analytical energy-range relationship has been developed and calibrated against well established experimental and Monte Carlo calculated energy-range data. Only published experimental data with a clear statement of accuracy and method of evaluation have been used. Besides published experimental range data for different uniform media, new accurate experimental data on the practical range of high-energy electron beams in water for the energy range 10-50 MeV from accurately calibrated racetrack microtrons have been used. Largely due to the simultaneous pooling of accurate experimental and Monte Carlo data for different materials, the fit has resulted in an increased accuracy of the resultant energy-range relationship, particularly at high energies. Up to date Monte Carlo data from the latest versions of the codes ITS3 and EGS4 for absorbers of atomic numbers between four and 92 (Be, C, H 2 O, PMMA, Al, Cu, Ag, Pb and U) and incident electron energies between 1 and 100 MeV have been used as a complement where experimental data are sparse or missing. The standard deviation of the experimental data relative to the new relation is slightly larger than that of the Monte Carlo data. This is partly due to the fact that theoretically based stopping and scattering cross-sections are used both to account for the material dependence of the analytical energy-range formula and to calculate ranges with the Monte Carlo programs. For water the deviation from the traditional energy-range relation of ICRU Report 35 is only 0.5% at 20 MeV but as high as - 2.2% at 50 MeV. An improved method for divergence and ionization correction in high-energy electron beams has also been developed to enable use of a wider range of experimental results. (Author)

  5. Kinase detection with gallium nitride based high electron mobility transistors.

    Science.gov (United States)

    Makowski, Matthew S; Bryan, Isaac; Sitar, Zlatko; Arellano, Consuelo; Xie, Jinqiao; Collazo, Ramon; Ivanisevic, Albena

    2013-07-01

    A label-free kinase detection system was fabricated by the adsorption of gold nanoparticles functionalized with kinase inhibitor onto AlGaN/GaN high electron mobility transistors (HEMTs). The HEMTs were operated near threshold voltage due to the greatest sensitivity in this operational region. The Au NP/HEMT biosensor system electrically detected 1 pM SRC kinase in ionic solutions. These results are pertinent to drug development applications associated with kinase sensing.

  6. High-resolution remotely sensed small target detection by imitating fly visual perception mechanism.

    Science.gov (United States)

    Huang, Fengchen; Xu, Lizhong; Li, Min; Tang, Min

    2012-01-01

    The difficulty and limitation of small target detection methods for high-resolution remote sensing data have been a recent research hot spot. Inspired by the information capture and processing theory of fly visual system, this paper endeavors to construct a characterized model of information perception and make use of the advantages of fast and accurate small target detection under complex varied nature environment. The proposed model forms a theoretical basis of small target detection for high-resolution remote sensing data. After the comparison of prevailing simulation mechanism behind fly visual systems, we propose a fly-imitated visual system method of information processing for high-resolution remote sensing data. A small target detector and corresponding detection algorithm are designed by simulating the mechanism of information acquisition, compression, and fusion of fly visual system and the function of pool cell and the character of nonlinear self-adaption. Experiments verify the feasibility and rationality of the proposed small target detection model and fly-imitated visual perception method.

  7. High-Resolution Remotely Sensed Small Target Detection by Imitating Fly Visual Perception Mechanism

    Directory of Open Access Journals (Sweden)

    Fengchen Huang

    2012-01-01

    Full Text Available The difficulty and limitation of small target detection methods for high-resolution remote sensing data have been a recent research hot spot. Inspired by the information capture and processing theory of fly visual system, this paper endeavors to construct a characterized model of information perception and make use of the advantages of fast and accurate small target detection under complex varied nature environment. The proposed model forms a theoretical basis of small target detection for high-resolution remote sensing data. After the comparison of prevailing simulation mechanism behind fly visual systems, we propose a fly-imitated visual system method of information processing for high-resolution remote sensing data. A small target detector and corresponding detection algorithm are designed by simulating the mechanism of information acquisition, compression, and fusion of fly visual system and the function of pool cell and the character of nonlinear self-adaption. Experiments verify the feasibility and rationality of the proposed small target detection model and fly-imitated visual perception method.

  8. Identification and accurate quantification of structurally related peptide impurities in synthetic human C-peptide by liquid chromatography-high resolution mass spectrometry.

    Science.gov (United States)

    Li, Ming; Josephs, Ralf D; Daireaux, Adeline; Choteau, Tiphaine; Westwood, Steven; Wielgosz, Robert I; Li, Hongmei

    2018-06-04

    Peptides are an increasingly important group of biomarkers and pharmaceuticals. The accurate purity characterization of peptide calibrators is critical for the development of reference measurement systems for laboratory medicine and quality control of pharmaceuticals. The peptides used for these purposes are increasingly produced through peptide synthesis. Various approaches (for example mass balance, amino acid analysis, qNMR, and nitrogen determination) can be applied to accurately value assign the purity of peptide calibrators. However, all purity assessment approaches require a correction for structurally related peptide impurities in order to avoid biases. Liquid chromatography coupled to high resolution mass spectrometry (LC-hrMS) has become the key technique for the identification and accurate quantification of structurally related peptide impurities in intact peptide calibrator materials. In this study, LC-hrMS-based methods were developed and validated in-house for the identification and quantification of structurally related peptide impurities in a synthetic human C-peptide (hCP) material, which served as a study material for an international comparison looking at the competencies of laboratories to perform peptide purity mass fraction assignments. More than 65 impurities were identified, confirmed, and accurately quantified by using LC-hrMS. The total mass fraction of all structurally related peptide impurities in the hCP study material was estimated to be 83.3 mg/g with an associated expanded uncertainty of 3.0 mg/g (k = 2). The calibration hierarchy concept used for the quantification of individual impurities is described in detail. Graphical abstract ᅟ.

  9. First Time Rapid and Accurate Detection of Massive Number of Metal Absorption Lines in the Early Universe Using Deep Neural Network

    Science.gov (United States)

    Zhao, Yinan; Ge, Jian; Yuan, Xiaoyong; Li, Xiaolin; Zhao, Tiffany; Wang, Cindy

    2018-01-01

    Metal absorption line systems in the distant quasar spectra have been used as one of the most powerful tools to probe gas content in the early Universe. The MgII λλ 2796, 2803 doublet is one of the most popular metal absorption lines and has been used to trace gas and global star formation at redshifts between ~0.5 to 2.5. In the past, machine learning algorithms have been used to detect absorption lines systems in the large sky survey, such as Principle Component Analysis, Gaussian Process and decision tree, but the overall detection process is not only complicated, but also time consuming. It usually takes a few months to go through the entire quasar spectral dataset from each of the Sloan Digital Sky Survey (SDSS) data release. In this work, we applied the deep neural network, or “ deep learning” algorithms, in the most recently SDSS DR14 quasar spectra and were able to randomly search 20000 quasar spectra and detect 2887 strong Mg II absorption features in just 9 seconds. Our detection algorithms were verified with previously released DR12 and DR7 data and published Mg II catalog and the detection accuracy is 90%. This is the first time that deep neural network has demonstrated its promising power in both speed and accuracy in replacing tedious, repetitive human work in searching for narrow absorption patterns in a big dataset. We will present our detection algorithms and also statistical results of the newly detected Mg II absorption lines.

  10. Voltage Based Detection Method for High Impedance Fault in a Distribution System

    Science.gov (United States)

    Thomas, Mini Shaji; Bhaskar, Namrata; Prakash, Anupama

    2016-09-01

    High-impedance faults (HIFs) on distribution feeders cannot be detected by conventional protection schemes, as HIFs are characterized by their low fault current level and waveform distortion due to the nonlinearity of the ground return path. This paper proposes a method to identify the HIFs in distribution system and isolate the faulty section, to reduce downtime. This method is based on voltage measurements along the distribution feeder and utilizes the sequence components of the voltages. Three models of high impedance faults have been considered and source side and load side breaking of the conductor have been studied in this work to capture a wide range of scenarios. The effect of neutral grounding of the source side transformer is also accounted in this study. The results show that the algorithm detects the HIFs accurately and rapidly. Thus, the faulty section can be isolated and service can be restored to the rest of the consumers.

  11. Highly specific detection of genetic modification events using an enzyme-linked probe hybridization chip.

    Science.gov (United States)

    Zhang, M Z; Zhang, X F; Chen, X M; Chen, X; Wu, S; Xu, L L

    2015-08-10

    The enzyme-linked probe hybridization chip utilizes a method based on ligase-hybridizing probe chip technology, with the principle of using thio-primers for protection against enzyme digestion, and using lambda DNA exonuclease to cut multiple PCR products obtained from the sample being tested into single-strand chains for hybridization. The 5'-end amino-labeled probe was fixed onto the aldehyde chip, and hybridized with the single-stranded PCR product, followed by addition of a fluorescent-modified probe that was then enzymatically linked with the adjacent, substrate-bound probe in order to achieve highly specific, parallel, and high-throughput detection. Specificity and sensitivity testing demonstrated that enzyme-linked probe hybridization technology could be applied to the specific detection of eight genetic modification events at the same time, with a sensitivity reaching 0.1% and the achievement of accurate, efficient, and stable results.

  12. Accurate CpG and non-CpG cytosine methylation analysis by high-throughput locus-specific pyrosequencing in plants.

    Science.gov (United States)

    How-Kit, Alexandre; Daunay, Antoine; Mazaleyrat, Nicolas; Busato, Florence; Daviaud, Christian; Teyssier, Emeline; Deleuze, Jean-François; Gallusci, Philippe; Tost, Jörg

    2015-07-01

    Pyrosequencing permits accurate quantification of DNA methylation of specific regions where the proportions of the C/T polymorphism induced by sodium bisulfite treatment of DNA reflects the DNA methylation level. The commercially available high-throughput locus-specific pyrosequencing instruments allow for the simultaneous analysis of 96 samples, but restrict the DNA methylation analysis to CpG dinucleotide sites, which can be limiting in many biological systems. In contrast to mammals where DNA methylation occurs nearly exclusively on CpG dinucleotides, plants genomes harbor DNA methylation also in other sequence contexts including CHG and CHH motives, which cannot be evaluated by these pyrosequencing instruments due to software limitations. Here, we present a complete pipeline for accurate CpG and non-CpG cytosine methylation analysis at single base-resolution using high-throughput locus-specific pyrosequencing. The devised approach includes the design and validation of PCR amplification on bisulfite-treated DNA and pyrosequencing assays as well as the quantification of the methylation level at every cytosine from the raw peak intensities of the Pyrograms by two newly developed Visual Basic Applications. Our method presents accurate and reproducible results as exemplified by the cytosine methylation analysis of the promoter regions of two Tomato genes (NOR and CNR) encoding transcription regulators of fruit ripening during different stages of fruit development. Our results confirmed a significant and temporally coordinated loss of DNA methylation on specific cytosines during the early stages of fruit development in both promoters as previously shown by WGBS. The manuscript describes thus the first high-throughput locus-specific DNA methylation analysis in plants using pyrosequencing.

  13. Accurate Evaluation of Quantum Integrals

    Science.gov (United States)

    Galant, D. C.; Goorvitch, D.; Witteborn, Fred C. (Technical Monitor)

    1995-01-01

    Combining an appropriate finite difference method with Richardson's extrapolation results in a simple, highly accurate numerical method for solving a Schrodinger's equation. Important results are that error estimates are provided, and that one can extrapolate expectation values rather than the wavefunctions to obtain highly accurate expectation values. We discuss the eigenvalues, the error growth in repeated Richardson's extrapolation, and show that the expectation values calculated on a crude mesh can be extrapolated to obtain expectation values of high accuracy.

  14. Highly accurate bound state calculations of the two-center molecular ions by using the universal variational expansion for three-body systems

    Science.gov (United States)

    Frolov, Alexei M.

    2018-03-01

    The universal variational expansion for the non-relativistic three-body systems is explicitly constructed. This universal expansion can be used to perform highly accurate numerical computations of the bound state spectra in various three-body systems, including Coulomb three-body systems with arbitrary particle masses and electric charges. Our main interest is related to the adiabatic three-body systems which contain one bound electron and two heavy nuclei of hydrogen isotopes: the protium p, deuterium d and tritium t. We also consider the analogous (model) hydrogen ion ∞H2+ with the two infinitely heavy nuclei.

  15. Prediction of collision cross section and retention time for broad scope screening in gradient reversed-phase liquid chromatography-ion mobility-high resolution accurate mass spectrometry

    DEFF Research Database (Denmark)

    Mollerup, Christian Brinch; Mardal, Marie; Dalsgaard, Petur Weihe

    2018-01-01

    artificial neural networks (ANNs). Prediction was based on molecular descriptors, 827 RTs, and 357 CCS values from pharmaceuticals, drugs of abuse, and their metabolites. ANN models for the prediction of RT or CCS separately were examined, and the potential to predict both from a single model......Exact mass, retention time (RT), and collision cross section (CCS) are used as identification parameters in liquid chromatography coupled to ion mobility high resolution accurate mass spectrometry (LC-IM-HRMS). Targeted screening analyses are now more flexible and can be expanded for suspect...

  16. Muon radiography technology for detecting high-Z materials

    International Nuclear Information System (INIS)

    Ma Lingling; Wang Wenxin; Zhou Jianrong; Sun Shaohua; Liu Zuoye; Li Lu; Du Hongchuan; Zhang Xiaodong; Hu Bitao

    2010-01-01

    This paper studies the possibility of using the scattering of cosmic muons to identify threatening high-Z materials. Various scenarios of threat material detection are simulated with the Geant4 toolkit. PoCA (Point of Closest Approach) algorithm reconstructing muon track gives 3D radiography images of the target material. Z-discrimination capability, effects of the placement of high-Z materials, shielding materials inside the cargo, and spatial resolution of position sensitive detector for muon radiography are carefully studied. Our results show that a detector position resolution of 50 μm is good enough for shielded materials detection. (authors)

  17. The research of high voltage switchgear detecting unit

    Science.gov (United States)

    Ji, Tong; Xie, Wei; Wang, Xiaoqing; Zhang, Jinbo

    2017-07-01

    In order to understand the status of the high voltage switch in the whole life circle, you must monitor the mechanical and electrical parameters that affect device health. So this paper gives a new high voltage switchgear detecting unit based on ARM technology. It can measure closing-opening mechanical wave, storage motor current wave and contactor temperature to judge the device’s health status. When something goes wrong, it can be on alert and give some advice. The practice showed that it can meet the requirements of circuit breaker mechanical properties temperature online detection.

  18. Detection of artifacts from high energy bursts in neonatal EEG.

    Science.gov (United States)

    Bhattacharyya, Sourya; Biswas, Arunava; Mukherjee, Jayanta; Majumdar, Arun Kumar; Majumdar, Bandana; Mukherjee, Suchandra; Singh, Arun Kumar

    2013-11-01

    Detection of non-cerebral activities or artifacts, intermixed within the background EEG, is essential to discard them from subsequent pattern analysis. The problem is much harder in neonatal EEG, where the background EEG contains spikes, waves, and rapid fluctuations in amplitude and frequency. Existing artifact detection methods are mostly limited to detect only a subset of artifacts such as ocular, muscle or power line artifacts. Few methods integrate different modules, each for detection of one specific category of artifact. Furthermore, most of the reference approaches are implemented and tested on adult EEG recordings. Direct application of those methods on neonatal EEG causes performance deterioration, due to greater pattern variation and inherent complexity. A method for detection of a wide range of artifact categories in neonatal EEG is thus required. At the same time, the method should be specific enough to preserve the background EEG information. The current study describes a feature based classification approach to detect both repetitive (generated from ECG, EMG, pulse, respiration, etc.) and transient (generated from eye blinking, eye movement, patient movement, etc.) artifacts. It focuses on artifact detection within high energy burst patterns, instead of detecting artifacts within the complete background EEG with wide pattern variation. The objective is to find true burst patterns, which can later be used to identify the Burst-Suppression (BS) pattern, which is commonly observed during newborn seizure. Such selective artifact detection is proven to be more sensitive to artifacts and specific to bursts, compared to the existing artifact detection approaches applied on the complete background EEG. Several time domain, frequency domain, statistical features, and features generated by wavelet decomposition are analyzed to model the proposed bi-classification between burst and artifact segments. A feature selection method is also applied to select the

  19. A novel approach to quench detection for high temperature superconducting coils

    International Nuclear Information System (INIS)

    Song, W.J.; Fang, X.Y.; Fang, J.; Wei, B.; Hou, J.Z.; Liu, L.F.; Lu, K.K.; Li, Shuo

    2015-01-01

    Highlights: • We proposed a novel quench detection method mainly based on phase for HTS coil. • We showed theory model and numerical simulation system by LabVIEW. • Experiment results are showed and analyzed. • Little quench voltage will cause obvious change on phase. • The approach can accurately detect quench resistance voltage in real-time. - Abstract: A novel approach to quench detection for high temperature superconducting (HTS) coils is proposed, which is mainly based on phase angle between voltage and current of two coils to detect the quench resistance voltage. The approach is analyzed theoretically, verified experimentally and analytically by MATLAB Simulink and LabVIEW. An analog quench circuit is built on Simulink and a quench alarm system program is written in LabVIEW. Experiment of quench detection is further conducted. The sinusoidal AC currents ranging from 19.9 A to 96 A are transported to the HTS coils, whose critical current is 90 A at 77 K. The results of analog simulation and experiment are analyzed and they show good consistency. It is shown that with the increase of current, the phase undergoes apparent growth, and it is up to 60° and 15° when the current reaches critical value experimentally and analytically, respectively. It is concluded that the approach proposed in this paper can meet the need of precision and quench resistance voltage can be detected in time.

  20. A novel approach to quench detection for high temperature superconducting coils

    Energy Technology Data Exchange (ETDEWEB)

    Song, W.J., E-mail: songwenjuan@bjtu.edu.cn [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); China Electric Power Research Institute, Beijing (China); Fang, X.Y. [Department of Electrical and Computer Engineering, University of Victoria, PO Box 1700, STN CSC, Victoria, BC V8W 2Y2 (Canada); Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Wei, B.; Hou, J.Z. [China Electric Power Research Institute, Beijing (China); Liu, L.F. [Guangzhou Metro Design & Research Institute Co., Ltd, Guangdong (China); Lu, K.K. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Shuo [College of Information Science and Engineering, Northeastern University, Shenyang (China)

    2015-11-15

    Highlights: • We proposed a novel quench detection method mainly based on phase for HTS coil. • We showed theory model and numerical simulation system by LabVIEW. • Experiment results are showed and analyzed. • Little quench voltage will cause obvious change on phase. • The approach can accurately detect quench resistance voltage in real-time. - Abstract: A novel approach to quench detection for high temperature superconducting (HTS) coils is proposed, which is mainly based on phase angle between voltage and current of two coils to detect the quench resistance voltage. The approach is analyzed theoretically, verified experimentally and analytically by MATLAB Simulink and LabVIEW. An analog quench circuit is built on Simulink and a quench alarm system program is written in LabVIEW. Experiment of quench detection is further conducted. The sinusoidal AC currents ranging from 19.9 A to 96 A are transported to the HTS coils, whose critical current is 90 A at 77 K. The results of analog simulation and experiment are analyzed and they show good consistency. It is shown that with the increase of current, the phase undergoes apparent growth, and it is up to 60° and 15° when the current reaches critical value experimentally and analytically, respectively. It is concluded that the approach proposed in this paper can meet the need of precision and quench resistance voltage can be detected in time.

  1. High-sensitivity detection of cardiac troponin I with UV LED excitation for use in point-of-care immunoassay

    OpenAIRE

    Rodenko, Olga; Eriksson, Susann; Tidemand-Lichtenberg, Peter; Troldborg, Carl Peder; Fodgaard, Henrik; van Os, Sylvana; Pedersen, Christian

    2017-01-01

    High-sensitivity cardiac troponin assay development enables determination of biological variation in healthy populations, more accurate interpretation of clinical results and points towards earlier diagnosis and rule-out of acute myocardial infarction. In this paper, we report on preliminary tests of an immunoassay analyzer employing an optimized LED excitation to measure on a standard troponin I and a novel research high-sensitivity troponin I assay. The limit of detection is improved by fac...

  2. Individual tree detection based on densities of high points of high resolution airborne lidar

    NARCIS (Netherlands)

    Abd Rahman, M.Z.; Gorte, B.G.H.

    2008-01-01

    The retrieval of individual tree location from Airborne LiDAR has focused largely on utilizing canopy height. However, high resolution Airborne LiDAR offers another source of information for tree detection. This paper presents a new method for tree detection based on high points’ densities from a

  3. Detectability of Gravitational Waves from High-Redshift Binaries.

    Science.gov (United States)

    Rosado, Pablo A; Lasky, Paul D; Thrane, Eric; Zhu, Xingjiang; Mandel, Ilya; Sesana, Alberto

    2016-03-11

    Recent nondetection of gravitational-wave backgrounds from pulsar timing arrays casts further uncertainty on the evolution of supermassive black hole binaries. We study the capabilities of current gravitational-wave observatories to detect individual binaries and demonstrate that, contrary to conventional wisdom, some are, in principle, detectable throughout the Universe. In particular, a binary with rest-frame mass ≳10^{10}M_{⊙} can be detected by current timing arrays at arbitrarily high redshifts. The same claim will apply for less massive binaries with more sensitive future arrays. As a consequence, future searches for nanohertz gravitational waves could be expanded to target evolving high-redshift binaries. We calculate the maximum distance at which binaries can be observed with pulsar timing arrays and other detectors, properly accounting for redshift and using realistic binary waveforms.

  4. Accurate evaluation of subband structure in a carrier accumulation layer at an n-type InAs surface: LDF calculation combined with high-resolution photoelectron spectroscopy

    Directory of Open Access Journals (Sweden)

    Takeshi Inaoka

    2012-12-01

    Full Text Available Adsorption on an n-type InAs surface often induces a gradual formation of a carrier-accumulation layer at the surface. By means of high-resolution photoelectron spectroscopy (PES, Betti et al. made a systematic observation of subbands in the accumulation layer in the formation process. Incorporating a highly nonparabolic (NP dispersion of the conduction band into the local-density-functional (LDF formalism, we examine the subband structure in the accumulation-layer formation process. Combining the LDF calculation with the PES experiment, we make an accurate evaluation of the accumulated-carrier density, the subband-edge energies, and the subband energy dispersion at each formation stage. Our theoretical calculation can reproduce the three observed subbands quantitatively. The subband dispersion, which deviates downward from that of the projected bulk conduction band with an increase in wave number, becomes significantly weaker in the formation process. Accurate evaluation of the NP subband dispersion at each formation stage is indispensable in making a quantitative analysis of collective electronic excitations and transport properties in the subbands.

  5. Detection of Patients at High Risk of Medication Errors

    DEFF Research Database (Denmark)

    Sædder, Eva Aggerholm; Lisby, Marianne; Nielsen, Lars Peter

    2016-01-01

    Medication errors (MEs) are preventable and can result in patient harm and increased expenses in the healthcare system in terms of hospitalization, prolonged hospitalizations and even death. We aimed to develop a screening tool to detect acutely admitted patients at low or high risk of MEs...

  6. Fiber based hydrophones for ultra-high energy neutrino detection

    NARCIS (Netherlands)

    Buis, E.J.; Doppenberg, E.J.J.; Eijk, D. van; Lahmann, R.; Nieuwland, R.A.; Toet, P.M.

    2014-01-01

    It is a well studied process [1, 2] that energy deposition of cosmic ray particles in water that generate thermo-acoustic signals. Hydrophones of sufficient sensitivity could measure this signal and provide a means of detecting ultra-high energetic cosmic neutrinos. We investigate optical

  7. Dynamical explanation for the high water abundance detected in Orion

    International Nuclear Information System (INIS)

    Elitzur, M.

    1979-01-01

    Shock wave chemistry is suggested as the likely explanation for the high water abundance which has been recently detected in Orion by Phyllips et al. The existence of such a shock and its inferred properties are in agreement with other observations of Orion such as the broad velocity feature and H 2 vibration emission. Shock waves are proposed as the likely explanation for high water abundances observed in other sources such as the strong H 2 O masers

  8. Infrared maritime target detection using the high order statistic filtering in fractional Fourier domain

    Science.gov (United States)

    Zhou, Anran; Xie, Weixin; Pei, Jihong

    2018-06-01

    Accurate detection of maritime targets in infrared imagery under various sea clutter conditions is always a challenging task. The fractional Fourier transform (FRFT) is the extension of the Fourier transform in the fractional order, and has richer spatial-frequency information. By combining it with the high order statistic filtering, a new ship detection method is proposed. First, the proper range of angle parameter is determined to make it easier for the ship components and background to be separated. Second, a new high order statistic curve (HOSC) at each fractional frequency point is designed. It is proved that maximal peak interval in HOSC reflects the target information, while the points outside the interval reflect the background. And the value of HOSC relative to the ship is much bigger than that to the sea clutter. Then, search the curve's maximal target peak interval and extract the interval by bandpass filtering in fractional Fourier domain. The value outside the peak interval of HOSC decreases rapidly to 0, so the background is effectively suppressed. Finally, the detection result is obtained by the double threshold segmenting and the target region selection method. The results show the proposed method is excellent for maritime targets detection with high clutters.

  9. Tracer test method and process data reconciliation based on VDI 2048. Comparison of two methods for highly accurate determination of feedwater massflow at NPP Beznau

    International Nuclear Information System (INIS)

    Hungerbuehler, T.; Langenstein, M.

    2007-01-01

    The feedwater mass flow is the key measured variable used to determine the thermal reactor output in a nuclear power plant. Usually this parameter is recorded via venturi nozzles of orifice plates. The problem with both principles of measurement, however, is that an accuracy of below 1% cannot be reached. In order to make more accurate statements about the feedwater amounts recirculated in the water-steam cycle, tracer measurements that offer an accuracy of up to 0.2% are used. In the NPP Beznau both methods have been used in parallel to determine the feedwater flow rates in 2004 (unit 1) and 2005 (unit 2). Comparison of the results shows that a high level of agreement is obtained between the results of the reconciliation and the results of the tracer measurements. As a result of the findings of this comparison, a high level of acceptance of process data reconciliation based on VDI 2048 was achieved. (orig.)

  10. Ab initio study of the CO-N2 complex: a new highly accurate intermolecular potential energy surface and rovibrational spectrum

    DEFF Research Database (Denmark)

    Cybulski, Hubert; Henriksen, Christian; Dawes, Richard

    2018-01-01

    A new, highly accurate ab initio ground-state intermolecular potential-energy surface (IPES) for the CO-N2 complex is presented. Thousands of interaction energies calculated with the CCSD(T) method and Dunning's aug-cc-pVQZ basis set extended with midbond functions were fitted to an analytical...... function. The global minimum of the potential is characterized by an almost T-shaped structure and has an energy of -118.2 cm-1. The symmetry-adapted Lanczos algorithm was used to compute rovibrational energies (up to J = 20) on the new IPES. The RMSE with respect to experiment was found to be on the order...... of 0.038 cm-1 which confirms the very high accuracy of the potential. This level of agreement is among the best reported in the literature for weakly bound systems and considerably improves on those of previously published potentials....

  11. Shadow Detection from Very High Resoluton Satellite Image Using Grabcut Segmentation and Ratio-Band Algorithms

    Science.gov (United States)

    Kadhim, N. M. S. M.; Mourshed, M.; Bray, M. T.

    2015-03-01

    Very-High-Resolution (VHR) satellite imagery is a powerful source of data for detecting and extracting information about urban constructions. Shadow in the VHR satellite imageries provides vital information on urban construction forms, illumination direction, and the spatial distribution of the objects that can help to further understanding of the built environment. However, to extract shadows, the automated detection of shadows from images must be accurate. This paper reviews current automatic approaches that have been used for shadow detection from VHR satellite images and comprises two main parts. In the first part, shadow concepts are presented in terms of shadow appearance in the VHR satellite imageries, current shadow detection methods, and the usefulness of shadow detection in urban environments. In the second part, we adopted two approaches which are considered current state-of-the-art shadow detection, and segmentation algorithms using WorldView-3 and Quickbird images. In the first approach, the ratios between the NIR and visible bands were computed on a pixel-by-pixel basis, which allows for disambiguation between shadows and dark objects. To obtain an accurate shadow candidate map, we further refine the shadow map after applying the ratio algorithm on the Quickbird image. The second selected approach is the GrabCut segmentation approach for examining its performance in detecting the shadow regions of urban objects using the true colour image from WorldView-3. Further refinement was applied to attain a segmented shadow map. Although the detection of shadow regions is a very difficult task when they are derived from a VHR satellite image that comprises a visible spectrum range (RGB true colour), the results demonstrate that the detection of shadow regions in the WorldView-3 image is a reasonable separation from other objects by applying the GrabCut algorithm. In addition, the derived shadow map from the Quickbird image indicates significant performance of

  12. SHADOW DETECTION FROM VERY HIGH RESOLUTON SATELLITE IMAGE USING GRABCUT SEGMENTATION AND RATIO-BAND ALGORITHMS

    Directory of Open Access Journals (Sweden)

    N. M. S. M. Kadhim

    2015-03-01

    Full Text Available Very-High-Resolution (VHR satellite imagery is a powerful source of data for detecting and extracting information about urban constructions. Shadow in the VHR satellite imageries provides vital information on urban construction forms, illumination direction, and the spatial distribution of the objects that can help to further understanding of the built environment. However, to extract shadows, the automated detection of shadows from images must be accurate. This paper reviews current automatic approaches that have been used for shadow detection from VHR satellite images and comprises two main parts. In the first part, shadow concepts are presented in terms of shadow appearance in the VHR satellite imageries, current shadow detection methods, and the usefulness of shadow detection in urban environments. In the second part, we adopted two approaches which are considered current state-of-the-art shadow detection, and segmentation algorithms using WorldView-3 and Quickbird images. In the first approach, the ratios between the NIR and visible bands were computed on a pixel-by-pixel basis, which allows for disambiguation between shadows and dark objects. To obtain an accurate shadow candidate map, we further refine the shadow map after applying the ratio algorithm on the Quickbird image. The second selected approach is the GrabCut segmentation approach for examining its performance in detecting the shadow regions of urban objects using the true colour image from WorldView-3. Further refinement was applied to attain a segmented shadow map. Although the detection of shadow regions is a very difficult task when they are derived from a VHR satellite image that comprises a visible spectrum range (RGB true colour, the results demonstrate that the detection of shadow regions in the WorldView-3 image is a reasonable separation from other objects by applying the GrabCut algorithm. In addition, the derived shadow map from the Quickbird image indicates

  13. Landslide detection using very high-resolution satellite imageries

    Science.gov (United States)

    Suga, Yuzo; Konishi, Tomohisa

    2012-10-01

    The heavy rain induced by the 12th typhoon caused landslide disaster at Kii Peninsula in the middle part of Japan. We propose a quick response method for landslide disaster mapping using very high resolution (VHR) satellite imageries. Especially, Synthetic Aperture Radar (SAR) is effective because it has the capability of all weather and day/night observation. In this study, multi-temporal COSMO-SkyMed imageries were used to detect the landslide areas. It was difficult to detect the landslide areas using only backscatter change pattern derived from pre- and post-disaster COSMOSkyMed imageries. Thus, the authors adopted a correlation analysis which the moving window was selected for the correlation coefficient calculation. Low value of the correlation coefficient reflects land cover change between pre- and post-disaster imageries. This analysis is effective for the detection of landslides using SAR data. The detected landslide areas were compared with the area detected by EROS-B high resolution optical image. In addition, we have developed 3D viewing system for geospatial visualizing of the damaged area using these satellite image data with digital elevation model. The 3D viewing system has the performance of geographic measurement with respect to elevation height, area and volume calculation, and cross section drawing including landscape viewing and image layer construction using a mobile personal computer with interactive operation. As the result, it was verified that a quick response for the detection of landslide disaster at the initial stage could be effectively performed using optical and SAR very high resolution satellite data by means of 3D viewing system.

  14. High mobility ZnO nanowires for terahertz detection applications

    International Nuclear Information System (INIS)

    Liu, Huiqiang; Peng, Rufang; Chu, Shijin; Chu, Sheng

    2014-01-01

    An oxide nanowire material was utilized for terahertz detection purpose. High quality ZnO nanowires were synthesized and field-effect transistors were fabricated. Electrical transport measurements demonstrated the nanowire with good transfer characteristics and fairly high electron mobility. It is shown that ZnO nanowires can be used as building blocks for the realization of terahertz detectors based on a one-dimensional plasmon detection configuration. Clear terahertz wave (∼0.3 THz) induced photovoltages were obtained at room temperature with varying incidence intensities. Further analysis showed that the terahertz photoresponse is closely related to the high electron mobility of the ZnO nanowire sample, which suggests that oxide nanoelectronics may find useful terahertz applications.

  15. Position sensitive detection of neutrons in high radiation background field.

    Science.gov (United States)

    Vavrik, D; Jakubek, J; Pospisil, S; Vacik, J

    2014-01-01

    We present the development of a high-resolution position sensitive device for detection of slow neutrons in the environment of extremely high γ and e(-) radiation background. We make use of a planar silicon pixelated (pixel size: 55 × 55 μm(2)) spectroscopic Timepix detector adapted for neutron detection utilizing very thin (10)B converter placed onto detector surface. We demonstrate that electromagnetic radiation background can be discriminated from the neutron signal utilizing the fact that each particle type produces characteristic ionization tracks in the pixelated detector. Particular tracks can be distinguished by their 2D shape (in the detector plane) and spectroscopic response using single event analysis. A Cd sheet served as thermal neutron stopper as well as intensive source of gamma rays and energetic electrons. Highly efficient discrimination was successful even at very low neutron to electromagnetic background ratio about 10(-4).

  16. Accurately Identifying New QoS Violation Driven by High-Distributed Low-Rate Denial of Service Attacks Based on Multiple Observed Features

    Directory of Open Access Journals (Sweden)

    Jian Kang

    2015-01-01

    Full Text Available We propose using multiple observed features of network traffic to identify new high-distributed low-rate quality of services (QoS violation so that detection accuracy may be further improved. For the multiple observed features, we choose F feature in TCP packet header as a microscopic feature and, P feature and D feature of network traffic as macroscopic features. Based on these features, we establish multistream fused hidden Markov model (MF-HMM to detect stealthy low-rate denial of service (LDoS attacks hidden in legitimate network background traffic. In addition, the threshold value is dynamically adjusted by using Kaufman algorithm. Our experiments show that the additive effect of combining multiple features effectively reduces the false-positive rate. The average detection rate of MF-HMM results in a significant 23.39% and 44.64% improvement over typical power spectrum density (PSD algorithm and nonparametric cumulative sum (CUSUM algorithm.

  17. Atomic spectroscopy and highly accurate measurement: determination of fundamental constants; Spectroscopie atomique et mesures de grande precision: determination de constantes fonfamentales

    Energy Technology Data Exchange (ETDEWEB)

    Schwob, C

    2006-12-15

    This document reviews the theoretical and experimental achievements of the author concerning highly accurate atomic spectroscopy applied for the determination of fundamental constants. A pure optical frequency measurement of the 2S-12D 2-photon transitions in atomic hydrogen and deuterium has been performed. The experimental setting-up is described as well as the data analysis. Optimized values for the Rydberg constant and Lamb shifts have been deduced (R = 109737.31568516 (84) cm{sup -1}). An experiment devoted to the determination of the fine structure constant with an aimed relative uncertainty of 10{sup -9} began in 1999. This experiment is based on the fact that Bloch oscillations in a frequency chirped optical lattice are a powerful tool to transfer coherently many photon momenta to the atoms. We have used this method to measure accurately the ratio h/m(Rb). The measured value of the fine structure constant is {alpha}{sub -1} = 137.03599884 (91) with a relative uncertainty of 6.7*10{sup -9}. The future and perspectives of this experiment are presented. This document presented before an academic board will allow his author to manage research work and particularly to tutor thesis students. (A.C.)

  18. High sensitive quench detection method using an integrated test wire

    International Nuclear Information System (INIS)

    Fevrier, A.; Tavergnier, J.P.; Nithart, H.; Kiblaire, M.; Duchateau, J.L.

    1981-01-01

    A high sensitive quench detection method which works even in the presence of an external perturbing magnetic field is reported. The quench signal is obtained from the difference in voltages at the superconducting winding terminals and at the terminals at a secondary winding strongly coupled to the primary. The secondary winding could consist of a ''zero-current strand'' of the superconducting cable not connected to one of the winding terminals or an integrated normal test wire inside the superconducting cable. Experimental results on quench detection obtained by this method are described. It is shown that the integrated test wire method leads to efficient and sensitive quench detection, especially in the presence of an external perturbing magnetic field

  19. HPNAIDM: The High-Performance Network Anomaly/Intrusion Detection and Mitigation System

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yan [Northwesten University

    2013-12-05

    Identifying traffic anomalies and attacks rapidly and accurately is critical for large network operators. With the rapid growth of network bandwidth, such as the next generation DOE UltraScience Network, and fast emergence of new attacks/virus/worms, existing network intrusion detection systems (IDS) are insufficient because they: • Are mostly host-based and not scalable to high-performance networks; • Are mostly signature-based and unable to adaptively recognize flow-level unknown attacks; • Cannot differentiate malicious events from the unintentional anomalies. To address these challenges, we proposed and developed a new paradigm called high-performance network anomaly/intrustion detection and mitigation (HPNAIDM) system. The new paradigm is significantly different from existing IDSes with the following features (research thrusts). • Online traffic recording and analysis on high-speed networks; • Online adaptive flow-level anomaly/intrusion detection and mitigation; • Integrated approach for false positive reduction. Our research prototype and evaluation demonstrate that the HPNAIDM system is highly effective and economically feasible. Beyond satisfying the pre-set goals, we even exceed that significantly (see more details in the next section). Overall, our project harvested 23 publications (2 book chapters, 6 journal papers and 15 peer-reviewed conference/workshop papers). Besides, we built a website for technique dissemination, which hosts two system prototype release to the research community. We also filed a patent application and developed strong international and domestic collaborations which span both academia and industry.

  20. Highly sensitive detection of urinary cadmium to assess personal exposure

    Energy Technology Data Exchange (ETDEWEB)

    Argun, Avni A.; Banks, Ashley M.; Merlen, Gwendolynne; Tempelman, Linda A. [Giner, Inc., 89 Rumford Ave., Newton 02466, MA United States (United States); Becker, Michael F.; Schuelke, Thomas [Fraunhofer USA – CCL, 1449 Engineering Research Ct., East Lansing 48824, MI (United States); Dweik, Badawi M., E-mail: bdweik@ginerinc.com [Giner, Inc., 89 Rumford Ave., Newton 02466, MA United States (United States)

    2013-04-22

    Highlights: ► An electrochemical sensor capable of detecting cadmium at parts-per-billion levels in urine. ► A novel fabrication method for Boron-Doped Diamond (BDD) ultramicroelectrode (UME) arrays. ► Unique combination of BDD UME arrays and a differential pulse voltammetry algorithm. ► High sensitivity, high reproducibility, and very low noise levels. ► Opportunity for portable operation to assess on-site personal exposure. -- Abstract: A series of Boron-Doped Diamond (BDD) ultramicroelectrode arrays were fabricated and investigated for their performance as electrochemical sensors to detect trace level metals such as cadmium. The steady-state diffusion behavior of these sensors was validated using cyclic voltammetry followed by electrochemical detection of cadmium in water and in human urine to demonstrate high sensitivity (>200 μA ppb{sup −1} cm{sup −2}) and low background current (<4 nA). When an array of ultramicroelectrodes was positioned with optimal spacing, these BDD sensors showed a sigmoidal diffusion behavior. They also demonstrated high accuracy with linear dose dependence for quantification of cadmium in a certified reference river water sample from the U.S. National Institute of Standards and Technology (NIST) as well as in a human urine sample spiked with 0.25–1 ppb cadmium.

  1. Profile parameters of wheelset detection for high speed freight train

    Science.gov (United States)

    Yang, Kai; Ma, Li; Gao, Xiaorong; Wang, Li

    2012-04-01

    Because of freight train, in China, transports goods on railway freight line throughout the country, it does not depart from or return to engine shed during a long phase, thus we cannot monitor the quality of wheel set effectively. This paper provides a system which uses leaser and high speed camera, applies no-contact light section technology to get precise wheel set profile parameters. The paper employs clamping-track method to avoid complex railway ballast modification project. And detailed descript an improved image-tracking algorithm to extract central line from profile curve. For getting one pixel width and continuous line of the profile curve, uses local gray maximum points as direction control points to direct tracking direction. The results based on practical experiment show the system adapted to detection environment of high speed and high vibration, and it can effectively detect the wheelset geometric parameters with high accuracy. The system fills the gaps in wheel set detection for freight train in main line and has an enlightening function on monitoring the quality of wheel set.

  2. A Highly Sensitive Chemiluminometric Assay for Real-Time Detection of Biological Hydrogen Peroxide Formation.

    Science.gov (United States)

    Zhu, Hong; Jia, Zhenquan; Trush, Michael A; Li, Y Robert

    2016-05-01

    Hydrogen peroxide (H 2 O 2 ) is a major reactive oxygen species (ROS) produced by various cellular sources, especially mitochondria. At high levels, H 2 O 2 causes oxidative stress, leading to cell injury, whereas at low concentrations, this ROS acts as an important second messenger to participate in cellular redox signaling. Detection and measurement of the levels or rates of production of cellular H 2 O 2 are instrumental in studying the biological effects of this major ROS. While a number of assays have been developed over the past decades for detecting and/or quantifying biological H 2 O 2 formation, none has been shown to be perfect. Perhaps there is no perfect assay for sensitively and accurately quantifying H 2 O 2 as well as other ROS in cells, wherein numerous potential reactants are present to interfere with the reliable measurement of the specific ROS. In this context, each assay has its own advantages and intrinsic limitations. This article describes a highly sensitive assay for real-time detection of H 2 O 2 formation in cultured cells and isolated mitochondria. This assay is based on the luminol/horseradish peroxidase-dependent chemiluminescence that is inhibitable by catalase. The article discusses the usefulness and shortcomings of this chemiluminometric assay in detecting biological H 2 O 2 formation induced by beta-lapachone redox cycling with both cells and isolated mitochondria.

  3. Auto Detection For High Level Water Content For Oil Well

    Science.gov (United States)

    Janier, Josefina Barnachea; Jumaludin, Zainul Arifin B.

    2010-06-01

    Auto detection of high level water content for oil well is a system that measures the percentage of water in crude oil. This paper aims to discuss an auto detection system for measuring the content of water level in crude oil which is applicable for offshore and onshore oil operations. Data regarding water level content from wells can be determined by using automation thus, well with high water level can be determined immediately whether to be closed or not from operations. Theoretically the system measures the percentage of two- fluid mixture where the fluids have different electrical conductivities which are water and crude oil. The system made use of grid sensor which is a grid pattern like of horizontal and vertical wires. When water occupies the space at the intersection of vertical and horizontal wires, an electrical signal is detected which proved that water completed the circuit path in the system. The electrical signals are counted whereas the percentage of water is determined from the total electrical signals detected over electrical signals provided. Simulation of the system using the MultiSIM showed that the system provided the desired result.

  4. Detection of Waterborne Viruses Using High Affinity Molecularly Imprinted Polymers.

    Science.gov (United States)

    Altintas, Zeynep; Gittens, Micah; Guerreiro, Antonio; Thompson, Katy-Anne; Walker, Jimmy; Piletsky, Sergey; Tothill, Ibtisam E

    2015-07-07

    Molecularly imprinted polymers (MIPs) are artificial receptor ligands which can recognize and specifically bind to a target molecule. They are more resistant to chemical and biological damage and inactivation than antibodies. Therefore, target specific-MIP nanoparticles are aimed to develop and implemented to biosensors for the detection of biological toxic agents such as viruses, bacteria, and fungi toxins that cause many diseases and death due to the environmental contamination. For the first time, a molecularly imprinted polymer (MIP) targeting the bacteriophage MS2 as the template was investigated using a novel solid-phase synthesis method to obtain the artificial affinity ligand for the detection and removal of waterborne viruses through optical-based sensors. A high affinity between the artificial ligand and the target was found, and a regenerative MIP-based virus detection assay was successfully developed using a new surface plasmon resonance (SPR)-biosensor which provides an alternative technology for the specific detection and removal of waterborne viruses that lead to high disease and death rates all over the world.

  5. Accurate mass analysis of ethanesulfonic acid degradates of acetochlor and alachlor using high-performance liquid chromatography and time-of-flight mass spectrometry

    Science.gov (United States)

    Thurman, E.M.; Ferrer, I.; Parry, R.

    2002-01-01

    Degradates of acetochlor and alachlor (ethanesulfonic acids, ESAs) were analyzed in both standards and in a groundwater sample using high-performance liquid chromatography-time-of-flight mass spectrometry with electrospray ionization. The negative pseudomolecular ion of the secondary amide of acetochlor ESA and alachlor ESA gave average masses of 256.0750??0.0049 amu and 270.0786??0.0064 amu respectively. Acetochlor and alachlor ESA gave similar masses of 314.1098??0.0061 amu and 314.1153??0.0048 amu; however, they could not be distinguished by accurate mass because they have the same empirical formula. On the other hand, they may be distinguished using positive-ion electrospray because of different fragmentation spectra, which did not occur using negative-ion electrospray.

  6. Charging and discharging tests for obtaining an accurate dynamic electro-thermal model of high power lithium-ion pack system for hybrid and EV applications

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Camacho, Oscar Mauricio Forero; Nørgård, Per Bromand

    2013-01-01

    This paper presents a battery test platform including two Li-ion battery designed for hybrid and EV applications, and charging/discharging tests under different operating conditions carried out for developing an accurate dynamic electro-thermal model of a high power Li-ion battery pack system....... The aim of the tests has been to study the impact of the battery degradation and to find out the dynamic characteristics of the cells including nonlinear open circuit voltage, series resistance and parallel transient circuit at different charge/discharge currents and cell temperature. An equivalent...... circuit model, based on the runtime battery model and the Thevenin circuit model, with parameters obtained from the tests and depending on SOC, current and temperature has been implemented in MATLAB/Simulink and Power Factory. A good alignment between simulations and measurements has been found....

  7. Albumin-Bilirubin and Platelet-Albumin-Bilirubin Grades Accurately Predict Overall Survival in High-Risk Patients Undergoing Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma.

    Science.gov (United States)

    Hansmann, Jan; Evers, Maximilian J; Bui, James T; Lokken, R Peter; Lipnik, Andrew J; Gaba, Ron C; Ray, Charles E

    2017-09-01

    To evaluate albumin-bilirubin (ALBI) and platelet-albumin-bilirubin (PALBI) grades in predicting overall survival in high-risk patients undergoing conventional transarterial chemoembolization for hepatocellular carcinoma (HCC). This single-center retrospective study included 180 high-risk patients (142 men, 59 y ± 9) between April 2007 and January 2015. Patients were considered high-risk based on laboratory abnormalities before the procedure (bilirubin > 2.0 mg/dL, albumin 1.2 mg/dL); presence of ascites, encephalopathy, portal vein thrombus, or transjugular intrahepatic portosystemic shunt; or Model for End-Stage Liver Disease score > 15. Serum albumin, bilirubin, and platelet values were used to determine ALBI and PALBI grades. Overall survival was stratified by ALBI and PALBI grades with substratification by Child-Pugh class (CPC) and Barcelona Liver Clinic Cancer (BCLC) stage using Kaplan-Meier analysis. C-index was used to determine discriminatory ability and survival prediction accuracy. Median survival for 79 ALBI grade 2 patients and 101 ALBI grade 3 patients was 20.3 and 10.7 months, respectively (P  .05). ALBI and PALBI grades are accurate survival metrics in high-risk patients undergoing conventional transarterial chemoembolization for HCC. Use of these scores allows for more refined survival stratification within CPC and BCLC stage. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

  8. High resolution PET breast imager with improved detection efficiency

    Science.gov (United States)

    Majewski, Stanislaw

    2010-06-08

    A highly efficient PET breast imager for detecting lesions in the entire breast including those located close to the patient's chest wall. The breast imager includes a ring of imaging modules surrounding the imaged breast. Each imaging module includes a slant imaging light guide inserted between a gamma radiation sensor and a photodetector. The slant light guide permits the gamma radiation sensors to be placed in close proximity to the skin of the chest wall thereby extending the sensitive region of the imager to the base of the breast. Several types of photodetectors are proposed for use in the detector modules, with compact silicon photomultipliers as the preferred choice, due to its high compactness. The geometry of the detector heads and the arrangement of the detector ring significantly reduce dead regions thereby improving detection efficiency for lesions located close to the chest wall.

  9. LAT Perspectives in Detection of High Energy Cosmic Ray Electrons

    International Nuclear Information System (INIS)

    Moiseev, Alexander; Ormes, J.F.; Funk, Stefan

    2007-01-01

    The LAT science objectives and capabilities in the detection of high energy electrons in the energy range from 20 GeV to ∼1.5 TeV are presented. LAT simulations are used to establish the event selections. It is found that maintaining the efficiency of electron detection at the level of 30%, the residual hadron contamination does not exceed 2-3% of the electron flux. It is expected to collect ∼ ten million of electrons with the energy above 20 GeV for one year of observation. Precise spectrum reconstruction with collected electron statistics opens the unique opportunity to investigate several important problems such as models of IC radiation, revealing the signatures of nearby sources such as high energy cutoff in the electron spectrum, testing the propagation model, and search for KKDM particles decay through their contribution to the electron spectrum

  10. Noise reduction in muon tomography for detecting high density objects

    International Nuclear Information System (INIS)

    Benettoni, M; Checchia, P; Cossutta, L; Furlan, M; Gonella, F; Pegoraro, M; Garola, A Rigoni; Ronchese, P; Vanini, S; Viesti, G; Bettella, G; Bonomi, G; Donzella, A; Subieta, M; Zenoni, A; Calvagno, G; Cortelazzo, G; Zanuttigh, P; Calvini, P; Squarcia, S

    2013-01-01

    The muon tomography technique, based on multiple Coulomb scattering of cosmic ray muons, has been proposed as a tool to detect the presence of high density objects inside closed volumes. In this paper a new and innovative method is presented to handle the density fluctuations (noise) of reconstructed images, a well known problem of this technique. The effectiveness of our method is evaluated using experimental data obtained with a muon tomography prototype located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (INFN). The results reported in this paper, obtained with real cosmic ray data, show that with appropriate image filtering and muon momentum classification, the muon tomography technique can detect high density materials, such as lead, albeit surrounded by light or medium density material, in short times. A comparison with algorithms published in literature is also presented

  11. Fiber optic quench detection via optimized Rayleigh Scattering in high-field YBCO accelerator magnets

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, Gene [North Carolina State Univ., Raleigh, NC (United States)

    2016-02-17

    Yttrium barium copper oxide (YBCO) coated conductors are known for their ability to operate in the superconducting state at relatively high temperatures, even above the boiling point of liquid nitrogen (77 K). When these same conductors are operated at lower temperatures, they are able to operate in much higher magnetic fields than traditional superconductors like NiTi or Nb3Sn. Thus, YBCO superconducting magnets are one of the primary options for generating the high magnetic fields needed for future high energy physics devices. Due to slow quench propagation, quench detection remains one of the primary limitations to YBCO magnets. Fiber optic sensing, based upon Rayleigh scattering, has the potential for spatial resolution approaching the wavelength of light, or very fast temporal resolution at low spatial resolution, and a continuum of combinations in between. This project has studied, theoretically and experimentally, YBCO magnets and Rayleigh scattering quench detection systems to demonstrate feasibility of the systems for YBCO quench protection systems. Under this grant an experimentally validated 3D quench propagation model was used to accurately define the acceptable range of spatial and temporal resolutions for effective quench detection in YBCO magnets and to evaluate present-day and potentially improved YBCO conductors. The data volume and speed requirements for quench detection via Rayleigh scattering required the development of a high performance fiber optic based quench detection/data acquisition system and its integration with an existing voltage tap/thermo-couple based system. In this project, optical fibers are tightly co-wound into YBCO magnet coils, with the fiber on top of the conductor as turn-to-turn insulation. Local changes in the temperature or strain of the conductor are sensed by the optical fiber, which is in close thermal and mechanical contact with the conductor. Intrinsic imperfections in the fiber reflect Rayleigh

  12. Detecting highly overlapping community structure by greedy clique expansion

    OpenAIRE

    Lee, Conrad; Reid, Fergal; McDaid, Aaron; Hurley, Neil

    2010-01-01

    In complex networks it is common for each node to belong to several communities, implying a highly overlapping community structure. Recent advances in benchmarking indicate that existing community assignment algorithms that are capable of detecting overlapping communities perform well only when the extent of community overlap is kept to modest levels. To overcome this limitation, we introduce a new community assignment algorithm called Greedy Clique Expansion (GCE). The algorithm identifies d...

  13. A hydrophone prototype for ultra high energy neutrino acoustic detection

    International Nuclear Information System (INIS)

    Cotrufo, A.; Plotnikov, A.; Yershova, O.; Anghinolfi, M.; Piombo, D.

    2009-01-01

    The design of an air-backed fiber-optic hydrophone is presented. With respect to the previous models this prototype is optimized to provide a bandwidth sufficiently large to detect acoustic signals produced by high energy hadronic showers in water. In addiction to the geometrical configuration and to the choice of the materials, the preliminary results of the measured performances in air are presented.

  14. A hydrophone prototype for ultra high energy neutrino acoustic detection

    Energy Technology Data Exchange (ETDEWEB)

    Cotrufo, A. [University of Genoa, Department of Physics, Via Dodecaneso 33, I-16146 (Italy)], E-mail: cotrufo@ge.infn.it; Plotnikov, A.; Yershova, O. [GSI Helmholtz Centre for Heavy Ion Research, GmbH Planckstrasse1, 64291 Darmstadt (Germany); Anghinolfi, M.; Piombo, D. [INFN, University of Genoa, Department of Physics, Via Dodecaneso 33, I-16146 (Italy)

    2009-06-01

    The design of an air-backed fiber-optic hydrophone is presented. With respect to the previous models this prototype is optimized to provide a bandwidth sufficiently large to detect acoustic signals produced by high energy hadronic showers in water. In addiction to the geometrical configuration and to the choice of the materials, the preliminary results of the measured performances in air are presented.

  15. High-resolution elastic recoil detection utilizing Bayesian probability theory

    International Nuclear Information System (INIS)

    Neumaier, P.; Dollinger, G.; Bergmaier, A.; Genchev, I.; Goergens, L.; Fischer, R.; Ronning, C.; Hofsaess, H.

    2001-01-01

    Elastic recoil detection (ERD) analysis is improved in view of depth resolution and the reliability of the measured spectra. Good statistics at even low ion fluences is obtained utilizing a large solid angle of 5 msr at the Munich Q3D magnetic spectrograph and using a 40 MeV 197 Au beam. In this way the elemental depth profiles are not essentially altered during analysis even if distributions with area densities below 1x10 14 atoms/cm 2 are measured. As the energy spread due to the angular acceptance is fully eliminated by ion-optical and numerical corrections, an accurate and reliable apparatus function is derived. It allows to deconvolute the measured spectra using the adaptive kernel method, a maximum entropy concept in the framework of Bayesian probability theory. In addition, the uncertainty of the reconstructed spectra is quantified. The concepts are demonstrated at 13 C depth profiles measured at ultra-thin films of tetrahedral amorphous carbon (ta-C). Depth scales of those profiles are given with an accuracy of 1.4x10 15 atoms/cm 2

  16. Detection of Fatigue Damage by Using High Frequency Nonlinear Laser Ultrasonic Signals

    International Nuclear Information System (INIS)

    Park, Seung Kyu; Park, Nak Kyu; Baik, Sung Hoon; Cheong, Yong Moo; Cha, Byung Heon

    2012-01-01

    The detection of fatigue damage for the components of a nuclear power plant is one of key techniques to prevent a catastrophic accident and the subsequent severe losses. Specifically, it is preferred to detect at an early stage of the fatigue damage. If the fatigue damage that is in danger of growing into a fracture is accurately detected, an appropriate treatment could be carried out to improve the condition. Although most engineers and designers take precautions against fatigue, some breakdowns of nuclear power plant components still occur due to fatigue damage. It is considered that ultrasound testing technique is the most promising method to detect the fatigue damage in many nondestructive testing methods. Laser ultrasound has attracted attention as a noncontact testing technique. Especially, laser ultrasonic signal has wide band frequency spectrum which can provide more accurate information for a testing material. The conventional linear ultrasonic technique is sensitive to gross defects or opened cracks whereas it is less sensitive to evenly distributed micro-cracks or degradation. An alternative technique to overcome this limitation is nonlinear ultrasound. The principal difference between linear and nonlinear technique is that in the latter the existence and characteristics of defects are often related to an acoustic signal whose frequency differs from that of the input signal. This is related to the radiation and propagation of finite amplitude, especially high power, ultrasound and its interaction with discontinuities, such as cracks, interfaces and voids. Since material failure or degradation is usually preceded by some kind of nonlinear mechanical behavior before significant plastic deformation or material damage occurs. The presence of nonlinear terms in the wave equation causes intense acoustic waves to generate new waves at frequencies which are multiples of the initial sound wave frequency. The nonlinear effect can exert a strong effect on the

  17. Ultrananocrystalline Diamond Membranes for Detection of High-Mass Proteins

    Science.gov (United States)

    Kim, H.; Park, J.; Aksamija, Z.; Arbulu, M.; Blick, R. H.

    2016-12-01

    Mechanical resonators realized on the nanoscale by now offer applications in mass sensing of biomolecules with extraordinary sensitivity. The general idea is that perfect mechanical mass sensors should be of extremely small size to achieve zepto- or yoctogram sensitivity in weighing single molecules similar to a classical scale. However, the small effective size and long response time for weighing biomolecules with a cantilever restricts their usefulness as a high-throughput method. Commercial mass spectrometry (MS), on the other hand, such as electrospray ionization and matrix-assisted laser desorption and ionization (MALDI) time of flight (TOF) and their charge-amplifying detectors are the gold standards to which nanomechanical resonators have to live up to. These two methods rely on the ionization and acceleration of biomolecules and the following ion detection after a mass selection step, such as TOF. The principle we describe here for ion detection is based on the conversion of kinetic energy of the biomolecules into thermal excitation of chemical vapor deposition diamond nanomembranes via phonons followed by phonon-mediated detection via field emission of thermally emitted electrons. We fabricate ultrathin diamond membranes with large lateral dimensions for MALDI TOF MS of high-mass proteins. These diamond membranes are realized by straightforward etching methods based on semiconductor processing. With a minimal thickness of 100 nm and cross sections of up to 400 ×400 μ m2 , the membranes offer extreme aspect ratios. Ion detection is demonstrated in MALDI TOF analysis over a broad range from insulin to albumin. The resulting data in detection show much enhanced resolution as compared to existing detectors, which can offer better sensitivity and overall performance in resolving protein masses.

  18. Detection of partial-thickness supraspinatus tendon tears: is a single direct MR arthrography series in ABER position as accurate as conventional MR arthrography?

    International Nuclear Information System (INIS)

    Schreinemachers, Saskia A.; Hulst, Victor P.M. van der; Woude, Henk-Jan van der; Willems, W.J.; Bipat, Shandra

    2009-01-01

    The purpose of this study was to retrospectively evaluate sensitivity and specificity of a single magnetic resonance (MR) arthrography series in abduction external rotation (ABER) position compared with conventional MR arthrography for detection of supraspinatus tendon tears, with arthroscopy as gold standard, and to assess interobserver variability. Institutional review board approval was obtained; informed consent was waived. MR arthrograms of 250 patients (170 men and 80 women; mean age, 36 years) were retrospectively and independently evaluated by three observers. Oblique coronal T1-weighted fat-suppressed images, proton density, and T2-weighted images and axial T1-weighted images and oblique sagittal T1-weighted fat-suppressed images were analyzed to detect supraspinatus tendon tears. Separately, a single T1-weighted fat-suppressed oblique axial series in ABER position was evaluated. Both protocols were scored randomly without knowledge of patients' clinical history and arthroscopy results. Tears were subclassified, based on articular surface integrity and extension (Lee classification). Interobserver agreement was assessed by kappa statistics for all patients. Ninety-two of 250 patients underwent arthroscopy; sensitivity and specificity of ABER and conventional MR arthrography were calculated and compared using paired McNemar test. Weighted kappa values of ABER and conventional MR arthrography were 0.48-0.65 and 0.60-0.67, respectively. According to arthroscopy, 69 of 92 patients had an intact cuff, and 23 patients had a cuff tear (16 partial thickness and seven full thickness). There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (48-61% and 52-70%, respectively) and specificity (80-94% and 91-95%). Sensitivity and specificity of a single T1-weighted series in ABER position and conventional MR arthrography are comparable for assessment of rotator cuff tears. (orig.)

  19. Detection of partial-thickness supraspinatus tendon tears: is a single direct MR arthrography series in ABER position as accurate as conventional MR arthrography?

    Energy Technology Data Exchange (ETDEWEB)

    Schreinemachers, Saskia A. [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Onze Lieve Vrouwe Gasthuis, Amsterdam (Netherlands); Hulst, Victor P.M. van der; Woude, Henk-Jan van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Willems, W.J. [Onze Lieve Vrouwe Gasthuis, Orthopaedic Surgery, Amsterdam (Netherlands); Bipat, Shandra [University of Amsterdam (NL). Department of Radiology, Academic Medical Center (Netherlands)

    2009-10-15

    The purpose of this study was to retrospectively evaluate sensitivity and specificity of a single magnetic resonance (MR) arthrography series in abduction external rotation (ABER) position compared with conventional MR arthrography for detection of supraspinatus tendon tears, with arthroscopy as gold standard, and to assess interobserver variability. Institutional review board approval was obtained; informed consent was waived. MR arthrograms of 250 patients (170 men and 80 women; mean age, 36 years) were retrospectively and independently evaluated by three observers. Oblique coronal T1-weighted fat-suppressed images, proton density, and T2-weighted images and axial T1-weighted images and oblique sagittal T1-weighted fat-suppressed images were analyzed to detect supraspinatus tendon tears. Separately, a single T1-weighted fat-suppressed oblique axial series in ABER position was evaluated. Both protocols were scored randomly without knowledge of patients' clinical history and arthroscopy results. Tears were subclassified, based on articular surface integrity and extension (Lee classification). Interobserver agreement was assessed by kappa statistics for all patients. Ninety-two of 250 patients underwent arthroscopy; sensitivity and specificity of ABER and conventional MR arthrography were calculated and compared using paired McNemar test. Weighted kappa values of ABER and conventional MR arthrography were 0.48-0.65 and 0.60-0.67, respectively. According to arthroscopy, 69 of 92 patients had an intact cuff, and 23 patients had a cuff tear (16 partial thickness and seven full thickness). There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (48-61% and 52-70%, respectively) and specificity (80-94% and 91-95%). Sensitivity and specificity of a single T1-weighted series in ABER position and conventional MR arthrography are comparable for assessment of rotator cuff tears. (orig.)

  20. Is a single direct MR arthrography series in ABER position as accurate in detecting anteroinferior labroligamentous lesions as conventional MR arthography?

    Energy Technology Data Exchange (ETDEWEB)

    Schreinemachers, Saskia A.; Hulst, Victor P.M. van der; Woude, Henk-Jan van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Jaap Willems, W. [Onze Lieve Vrouwe Gasthuis, Orthopaedic Surgery, Amsterdam (Netherlands); Bipat, Shandra [University of Amsterdam, Department of Radiology, Academic Medical Centre, Amsterdam (Netherlands)

    2009-07-15

    The purpose of this study is to retrospectively compare accuracy of single magnetic resonance (MR) arthrography series in Abduction External Rotation (ABER) with conventional MR arthrography for detection and characterisation of anteroinferior labroligamentous lesions, with arthroscopy as reference standard. Inter-observer variability of both protocols was determined. Institutional review board approval was obtained; informed consent was waived. MR arthrograms, including oblique axial fat suppressed T1-weighted images in ABER position and conventional imaging directions of 250 patients (170 men, 80 women; mean age, 36 years), were retrospectively and independently evaluated by three reviewers. Reviewers were blinded to clinical information and arthroscopic results. Labroligamentous lesions were registered in both ABER and MRa. The lesions were sub-classified (Bankart, Perthes, anterior labrum periosteal sleeve avulsion (ALPSA) or lesions not otherwise specified). Inter-observer agreement was assessed by Kappa statistics for all 250 patients. Ninety-two of 250 patients underwent arthroscopy. Sensitivity, specificity and accuracy of ABER versus conventional MR arthrography were calculated and compared using paired McNemar test. Kappa values of the ABER and conventional MR arthrography ranged from 0.44 to 0.56 and 0.44 to 0.62, respectively. According to arthroscopy, 45 of 92 patients had an intact anteroinferior labrum, and in 44 patients, a labroligamentous lesion (eight Bankart, seven Perthes, 29 ALPSA and three lesions not otherwise specified) was diagnosed. There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (85-89%, 89-96%), specificity (82-91%, 84-89%) and overall accuracy (50-62%, 53-63%). The results of a single MR arthrography series in ABER position are comparable with those of conventional MR arthrography for detecting anteroinferior labroligamentous lesions. (orig.)

  1. DIRAC: A high resolution spectrometer for pionium detection

    Energy Technology Data Exchange (ETDEWEB)

    Adeva, B. E-mail: adevab@usc.es; Afanasyev, L.; Benayoun, M.; Benelli, A.; Berka, Z.; Brekhovskikh, V.; Caragheorgheopol, G.; Cechak, T.; Chiba, M.; Cima, E.; Constantinescu, S.; Detraz, C.; Dreossi, D.; Drijard, D.; Dudarev, A.; Evangelou, I.; Ferro-Luzzi, M.; Gallas, M.V.; Gerndt, J.; Giacomich, R.; Gianotti, P.; Giardoni, M.; Goldin, D.; Gomez, F.; Gorin, A.; Gortchakov, O.; Guaraldo, C.; Hansroul, M.; Iliescu, M.; Zhabitsky, M.; Karpukhin, V.; Kluson, J.; Kobayashi, M.; Kokkas, P.; Komarov, V.; Kruglov, V.; Kruglova, L.; Kulikov, A.; Kuptsov, A.; Kurochkin, V.; Kuroda, K.-I.; Lamberto, A.; Lanaro, A.; Lapshin, V.; Lednicky, R.; Leruste, P.; Levisandri, P.; Lopez Aguera, A.; Lucherini, V.; Maki, T.; Manthos, N.; Manuilov, I.; Montanet, L.; Narjoux, J.-L.; Nemenov, L.; Nikitin, M.; Nunez Pardo, T.; Okada, K.; Olchevskii, V.; Orecchini, D.; Pazos, A.; Pentia, M.; Penzo, A.; Perreau, J.-M.; Petrascu, C.; Plo, M.; Ponta, T.; Pop, D.; Rappazzo, G.F.; Riazantsev, A.; Rodriguez, J.M.; Rodriguez Fernandez, A.; Romero, A.; Rykalin, V.; Santamarina, C.; Saborido, J.; Schacher, J.; Schuetz, Ch.P.; Sidorov, A.; Smolik, J.; Steinacher, M.; Takeutchi, F.; Tarasov, A.; Tauscher, L.; Tobar, M.J.; Triantis, F.; Trusov, S.; Utkin, V.; Vazquez Doce, O.; Vazquez, P.; Vlachos, S.; Yazkov, V.; Yoshimura, Y.; Zrelov, P

    2003-12-11

    The DIRAC spectrometer has been commissioned at CERN with the aim of detecting {pi}{sup +}{pi}{sup -} atoms produced by a 24 GeV/c high intensity proton beam in thin foil targets. A challenging apparatus is required to cope with the high interaction rates involved, the triggering of pion pairs with very detector efficiency.ation of the imaging sof the latter with resolution around 0.6 MeV/c. The general characteristics of the apparatus are explained and each part is described in some detail. The main features of the trigger system, data-acquisition, monitoring and set-up performances are also given.

  2. DIRAC: A high resolution spectrometer for pionium detection

    International Nuclear Information System (INIS)

    Adeva, B.; Afanasyev, L.; Benayoun, M.; Benelli, A.; Berka, Z.; Brekhovskikh, V.; Caragheorgheopol, G.; Cechak, T.; Chiba, M.; Cima, E.; Constantinescu, S.; Detraz, C.; Dreossi, D.; Drijard, D.; Dudarev, A.; Evangelou, I.; Ferro-Luzzi, M.; Gallas, M.V.; Gerndt, J.; Giacomich, R.; Gianotti, P.; Giardoni, M.; Goldin, D.; Gomez, F.; Gorin, A.; Gortchakov, O.; Guaraldo, C.; Hansroul, M.; Iliescu, M.; Zhabitsky, M.; Karpukhin, V.; Kluson, J.; Kobayashi, M.; Kokkas, P.; Komarov, V.; Kruglov, V.; Kruglova, L.; Kulikov, A.; Kuptsov, A.; Kurochkin, V.; Kuroda, K.-I.; Lamberto, A.; Lanaro, A.; Lapshin, V.; Lednicky, R.; Leruste, P.; Levisandri, P.; Lopez Aguera, A.; Lucherini, V.; Maki, T.; Manthos, N.; Manuilov, I.; Montanet, L.; Narjoux, J.-L.; Nemenov, L.; Nikitin, M.; Nunez Pardo, T.; Okada, K.; Olchevskii, V.; Orecchini, D.; Pazos, A.; Pentia, M.; Penzo, A.; Perreau, J.-M.; Petrascu, C.; Plo, M.; Ponta, T.; Pop, D.; Rappazzo, G.F.; Riazantsev, A.; Rodriguez, J.M.; Rodriguez Fernandez, A.; Romero, A.; Rykalin, V.; Santamarina, C.; Saborido, J.; Schacher, J.; Schuetz, Ch.P.; Sidorov, A.; Smolik, J.; Steinacher, M.; Takeutchi, F.; Tarasov, A.; Tauscher, L.; Tobar, M.J.; Triantis, F.; Trusov, S.; Utkin, V.; Vazquez Doce, O.; Vazquez, P.; Vlachos, S.; Yazkov, V.; Yoshimura, Y.; Zrelov, P.

    2003-01-01

    The DIRAC spectrometer has been commissioned at CERN with the aim of detecting π + π - atoms produced by a 24 GeV/c high intensity proton beam in thin foil targets. A challenging apparatus is required to cope with the high interaction rates involved, the triggering of pion pairs with very detector efficiency.ation of the imaging sof the latter with resolution around 0.6 MeV/c. The general characteristics of the apparatus are explained and each part is described in some detail. The main features of the trigger system, data-acquisition, monitoring and set-up performances are also given

  3. DIRAC: A High Resolution Spectrometer for Pionium Detection

    CERN Document Server

    Afanasiev, L G; Benelli, A; Berka, Z; Brekhovskikh, V; Caragheorgheopol, G; Cechák, T; Chiba, M; Cima, E; Constantinescu, S; Détraz, C; Dreossi, D; Drijard, Daniel; Dudarev, A; Evangelou, I; Ferro-Luzzi, M; Gallas, M V; Gerndt, J; Giacomich, R; Gianotti, P; Giardoni, M; Goldin, D; Gómez, F; Gorin, A; Gortchakov, O E; Guaraldo, C; Hansroul, M; Iliescu, M A; Zhabitsky, V M; Karpukhin, V V; Kluson, J; Kobayashi, M; Kokkas, P; Komarov, V; Kruglov, V; Kruglova, L; Kulikov, A; Kuptsov, A; Kurochkin, V; Kuroda, K I; Lamberto, A; Lanaro, A; Lapshin, V G; Lednicky, R; Leruste, P; Levisandri, P; López-Aguera, A; Lucherini, V; Mäki, T; Manthos, N; Manuilov, I V; Montanet, Lucien; Narjoux, J L; Nemenov, Leonid L; Nikitin, M; Núñez-Pardo de Vera, M T; Okada, K; Olchevskii, V; Orecchini, D; Pazos, A; Pentia, M; Penzo, Aldo L; Perreau, J M; Petrascu, C; Pló, M; Ponta, T; Pop, D; Rappazzo, G F; Riazantsev, A; Rodríguez, J M; Rodríguez-Fernández, A M; Romero, A; Rykalin, V I; Santamarina-Rios, C; Saborido, J; Schacher, J; Schütz, C P; Sidorov, A; Smolik, J; Steinacher, M; Takeutchi, F; Tarasov, A; Tauscher, Ludwig; Tobar, M J; Triantis, F A; Trusov, S V; Utkin, V; Vázquez-Doce, O; Vázquez, P; Vlachos, S; Yazkov, V; Yoshimura, Y; Zrelov, V P

    2003-01-01

    The DIRAC spectrometer has been commissioned at CERN with the aim of detecting $\\pi^+ \\pi^-$ atoms produced by a 24 GeV/$c$ high intensity proton beam in thin foil targets. A challenging apparatus is required to cope with the high interaction rates involved, the triggering of pion pairs with very low relative momentum, and the measurement of the latter with resolution around 0.6 MeV/$c$. The general characteristics of the apparatus are explained and each part is described in some detail. The main features of the trigger system, data-acquisition, monitoring and setup performances are also given.

  4. Nonlinear detection for a high rate extended binary phase shift keying system.

    Science.gov (United States)

    Chen, Xian-Qing; Wu, Le-Nan

    2013-03-28

    The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM) on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD) detector. The two detectors detect the received signals together with the special impacting filter (SIF) that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs), which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK) signal detection and can provide accurate posterior probability for LDPC decoding.

  5. Nonlinear Detection for a High Rate Extended Binary Phase Shift Keying System

    Directory of Open Access Journals (Sweden)

    Le-Nan Wu

    2013-03-01

    Full Text Available The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD detector. The two detectors detect the received signals together with the special impacting filter (SIF that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs, which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK signal detection and can provide accurate posterior probability for LDPC decoding.

  6. Optical intensity modulation direct detection versus heterodyne detection: A high-SNR capacity comparison

    KAUST Repository

    Chaaban, Anas

    2016-09-15

    An optical wireless communications system which employs either intensity-modulation and direct-detection (IM-DD) or heterodyne detection (HD) is considered. IM-DD has lower complexity and cost than HD, but on the other hand, has lower capacity. It is therefore interesting to investigate the capacity gap between the two systems. The main focus of this paper is to investigate this gap at high SNR. Bounds on this gap are established for two cases: between IM-DD and HD, and between IM-DD and an HD-PAM which is an HD system employing pulse-amplitude modulation (PAM). While the gap between IM-DD and HD increases as the signal-to-noise ratio (SNR) increases, the gap between IM-DD and an HD-PAM is upper bounded by a constant at high SNR. © 2015 IEEE.

  7. Optical intensity modulation direct detection versus heterodyne detection: A high-SNR capacity comparison

    KAUST Repository

    Chaaban, Anas; Alouini, Mohamed-Slim

    2016-01-01

    An optical wireless communications system which employs either intensity-modulation and direct-detection (IM-DD) or heterodyne detection (HD) is considered. IM-DD has lower complexity and cost than HD, but on the other hand, has lower capacity. It is therefore interesting to investigate the capacity gap between the two systems. The main focus of this paper is to investigate this gap at high SNR. Bounds on this gap are established for two cases: between IM-DD and HD, and between IM-DD and an HD-PAM which is an HD system employing pulse-amplitude modulation (PAM). While the gap between IM-DD and HD increases as the signal-to-noise ratio (SNR) increases, the gap between IM-DD and an HD-PAM is upper bounded by a constant at high SNR. © 2015 IEEE.

  8. High Altitude Aerial Natural Gas Leak Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Richard T. Wainner; Mickey B. Frish; B. David Green; Matthew C. Laderer; Mark G. Allen; Joseph R. Morency

    2006-12-31

    The objective of this program was to develop and demonstrate a cost-effective and power-efficient advanced standoff sensing technology able to detect and quantify, from a high-altitude (> 10,000 ft) aircraft, natural gas leaking from a high-pressure pipeline. The advanced technology is based on an enhanced version of the Remote Methane Leak Detector (RMLD) platform developed previously by Physical Sciences Inc. (PSI). The RMLD combines a telecommunications-style diode laser, fiber-optic components, and low-cost DSP electronics with the well-understood principles of Wavelength Modulation Spectroscopy (WMS), to indicate the presence of natural gas located between the operator and a topographic target. The transceiver transmits a laser beam onto a topographic target and receives some of the laser light reflected by the target. The controller processes the received light signal to deduce the amount of methane in the laser's path. For use in the airborne platform, we modified three aspects of the RMLD, by: (1) inserting an Erbium-doped optical fiber laser amplifier to increase the transmitted laser power from 10 mW to 5W; (2) increasing the optical receiver diameter from 10 cm to 25 cm; and (3) altering the laser wavelength from 1653 nm to 1618 nm. The modified RMLD system provides a path-integrated methane concentration sensitivity {approx}5000 ppm-m, sufficient to detect the presence of a leak from a high capacity transmission line while discriminating against attenuation by ambient methane. In ground-based simulations of the aerial leak detection scenario, we demonstrated the ability to measure methane leaks within the laser beam path when it illuminates a topographic target 2000 m away. We also demonstrated simulated leak detection from ranges of 200 m using the 25 cm optical receiver without the fiber amplifier.

  9. Molecular Approaches for High Throughput Detection and Quantification of Genetically Modified Crops: A Review

    Directory of Open Access Journals (Sweden)

    Ibrahim B. Salisu

    2017-10-01

    Full Text Available As long as the genetically modified crops are gaining attention globally, their proper approval and commercialization need accurate and reliable diagnostic methods for the transgenic content. These diagnostic techniques are mainly divided into two major groups, i.e., identification of transgenic (1 DNA and (2 proteins from GMOs and their products. Conventional methods such as PCR (polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA were routinely employed for DNA and protein based quantification respectively. Although, these Techniques (PCR and ELISA are considered as significantly convenient and productive, but there is need for more advance technologies that allow for high throughput detection and the quantification of GM event as the production of more complex GMO is increasing day by day. Therefore, recent approaches like microarray, capillary gel electrophoresis, digital PCR and next generation sequencing are more promising due to their accuracy and precise detection of transgenic contents. The present article is a brief comparative study of all such detection techniques on the basis of their advent, feasibility, accuracy, and cost effectiveness. However, these emerging technologies have a lot to do with detection of a specific event, contamination of different events and determination of fusion as well as stacked gene protein are the critical issues to be addressed in future.

  10. High Precision Edge Detection Algorithm for Mechanical Parts

    Directory of Open Access Journals (Sweden)

    Duan Zhenyun

    2018-04-01

    Full Text Available High precision and high efficiency measurement is becoming an imperative requirement for a lot of mechanical parts. So in this study, a subpixel-level edge detection algorithm based on the Gaussian integral model is proposed. For this purpose, the step edge normal section line Gaussian integral model of the backlight image is constructed, combined with the point spread function and the single step model. Then gray value of discrete points on the normal section line of pixel edge is calculated by surface interpolation, and the coordinate as well as gray information affected by noise is fitted in accordance with the Gaussian integral model. Therefore, a precise location of a subpixel edge was determined by searching the mean point. Finally, a gear tooth was measured by M&M3525 gear measurement center to verify the proposed algorithm. The theoretical analysis and experimental results show that the local edge fluctuation is reduced effectively by the proposed method in comparison with the existing subpixel edge detection algorithms. The subpixel edge location accuracy and computation speed are improved. And the maximum error of gear tooth profile total deviation is 1.9 μm compared with measurement result with gear measurement center. It indicates that the method has high reliability to meet the requirement of high precision measurement.

  11. High Precision Edge Detection Algorithm for Mechanical Parts

    Science.gov (United States)

    Duan, Zhenyun; Wang, Ning; Fu, Jingshun; Zhao, Wenhui; Duan, Boqiang; Zhao, Jungui

    2018-04-01

    High precision and high efficiency measurement is becoming an imperative requirement for a lot of mechanical parts. So in this study, a subpixel-level edge detection algorithm based on the Gaussian integral model is proposed. For this purpose, the step edge normal section line Gaussian integral model of the backlight image is constructed, combined with the point spread function and the single step model. Then gray value of discrete points on the normal section line of pixel edge is calculated by surface interpolation, and the coordinate as well as gray information affected by noise is fitted in accordance with the Gaussian integral model. Therefore, a precise location of a subpixel edge was determined by searching the mean point. Finally, a gear tooth was measured by M&M3525 gear measurement center to verify the proposed algorithm. The theoretical analysis and experimental results show that the local edge fluctuation is reduced effectively by the proposed method in comparison with the existing subpixel edge detection algorithms. The subpixel edge location accuracy and computation speed are improved. And the maximum error of gear tooth profile total deviation is 1.9 μm compared with measurement result with gear measurement center. It indicates that the method has high reliability to meet the requirement of high precision measurement.

  12. Tsunami Arrival Detection with High Frequency (HF Radar

    Directory of Open Access Journals (Sweden)

    Donald Barrick

    2012-05-01

    Full Text Available Quantitative real-time observations of a tsunami have been limited to deep-water, pressure-sensor observations of changes in the sea surface elevation and observations of sea level fluctuations at the coast, which are essentially point measurements. Constrained by these data, models have been used for predictions and warning of the arrival of a tsunami, but to date no system exists for local detection of an actual incoming wave with a significant warning capability. Networks of coastal high frequency (HF-radars are now routinely observing surface currents in many countries. We report here on an empirical method for the detection of the initial arrival of a tsunami, and demonstrate its use with results from data measured by fourteen HF radar sites in Japan and USA following the magnitude 9.0 earthquake off Sendai, Japan, on 11 March 2011. The distance offshore at which the tsunami can be detected, and hence the warning time provided, depends on the bathymetry: the wider the shallow continental shelf, the greater this time. We compare arrival times at the radars with those measured by neighboring tide gauges. Arrival times measured by the radars preceded those at neighboring tide gauges by an average of 19 min (Japan and 15 min (USA The initial water-height increase due to the tsunami as measured by the tide gauges was moderate, ranging from 0.3 to 2 m. Thus it appears possible to detect even moderate tsunamis using this method. Larger tsunamis could obviously be detected further from the coast. We find that tsunami arrival within the radar coverage area can be announced 8 min (i.e., twice the radar spectral time resolution after its first appearance. This can provide advance warning of the tsunami approach to the coastline locations.

  13. Supervised detection of exoplanets in high-contrast imaging sequences

    Science.gov (United States)

    Gomez Gonzalez, C. A.; Absil, O.; Van Droogenbroeck, M.

    2018-06-01

    Context. Post-processing algorithms play a key role in pushing the detection limits of high-contrast imaging (HCI) instruments. State-of-the-art image processing approaches for HCI enable the production of science-ready images relying on unsupervised learning techniques, such as low-rank approximations, for generating a model point spread function (PSF) and subtracting the residual starlight and speckle noise. Aims: In order to maximize the detection rate of HCI instruments and survey campaigns, advanced algorithms with higher sensitivities to faint companions are needed, especially for the speckle-dominated innermost region of the images. Methods: We propose a reformulation of the exoplanet detection task (for ADI sequences) that builds on well-established machine learning techniques to take HCI post-processing from an unsupervised to a supervised learning context. In this new framework, we present algorithmic solutions using two different discriminative models: SODIRF (random forests) and SODINN (neural networks). We test these algorithms on real ADI datasets from VLT/NACO and VLT/SPHERE HCI instruments. We then assess their performances by injecting fake companions and using receiver operating characteristic analysis. This is done in comparison with state-of-the-art ADI algorithms, such as ADI principal component analysis (ADI-PCA). Results: This study shows the improved sensitivity versus specificity trade-off of the proposed supervised detection approach. At the diffraction limit, SODINN improves the true positive rate by a factor ranging from 2 to 10 (depending on the dataset and angular separation) with respect to ADI-PCA when working at the same false-positive level. Conclusions: The proposed supervised detection framework outperforms state-of-the-art techniques in the task of discriminating planet signal from speckles. In addition, it offers the possibility of re-processing existing HCI databases to maximize their scientific return and potentially improve

  14. Hexagonal boron nitride neutron detectors with high detection efficiencies

    Science.gov (United States)

    Maity, A.; Grenadier, S. J.; Li, J.; Lin, J. Y.; Jiang, H. X.

    2018-01-01

    Neutron detectors fabricated from 10B enriched hexagonal boron nitride (h-10BN or h-BN) epilayers have demonstrated the highest thermal neutron detection efficiency among solid-state neutron detectors to date at about 53%. In this work, photoconductive-like vertical detectors with a detection area of 1 × 1 mm2 were fabricated from 50 μm thick free-standing h-BN epilayers using Ni/Au and Ti/Al bilayers as ohmic contacts. Leakage currents, mobility-lifetime (μτ) products under UV photoexcitation, and neutron detection efficiencies have been measured for a total of 16 different device configurations. The results have unambiguously identified that detectors incorporating the Ni/Au bilayer on both surfaces as ohmic contacts and using the negatively biased top surface for neutron irradiation are the most desired device configurations. It was noted that high growth temperatures of h-10BN epilayers on sapphire substrates tend to yield a higher concentration of oxygen impurities near the bottom surface, leading to a better device performance by the chosen top surface for irradiation than by the bottom. Preferential scattering of oxygen donors tends to reduce the mobility of holes more than that of electrons, making the biasing scheme with the ability of rapidly extracting holes at the irradiated surface while leaving the electrons to travel a large average distance inside the detector at a preferred choice. When measured against a calibrated 6LiF filled micro-structured semiconductor neutron detector, it was shown that the optimized configuration has pushed the detection efficiency of h-BN neutron detectors to 58%. These detailed studies also provided a better understanding of growth-mediated impurities in h-BN epilayers and their effects on the charge collection and neutron detection efficiencies.

  15. Radar detection of ultra high energy cosmic rays

    Science.gov (United States)

    Myers, Isaac J.

    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment co-located with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, UT. The TARA detector combines a 40 kW transmitter and high gain transmitting antenna which broadcasts the radar carrier over the SD array and in the FD field of view to a 250 MS/s DAQ receiver. Data collection began in August, 2013. TARA stands apart from other cosmic ray radar experiments in that radar data is directly compared with conventional cosmic ray detector events. The transmitter is also directly controlled by TARA researchers. Waveforms from the FD-triggered data stream are time-matched with TA events and searched for signal using a novel signal search technique in which the expected (simulated) radar echo of a particular air shower is used as a matched filter template and compared to radio waveforms. This technique is used to calculate the radar cross-section (RCS) upper-limit on all triggers that correspond to well-reconstructed TA FD monocular events. Our lowest cosmic ray RCS upper-limit is 42 cm2 for an 11 EeV event. An introduction to cosmic rays is presented with the evolution of detection and the necessity of new detection techniques, of which radar detection is a candidate. The software simulation of radar scattering from cosmic rays follows. The TARA detector, including transmitter and receiver systems, are discussed in detail. Our search algorithm and methodology for calculating RCS is presented for the purpose of being repeatable. Search results are explained in context of the usefulness and future of cosmic ray radar detection.

  16. High resolution capacitance detection circuit for rotor micro-gyroscope

    Directory of Open Access Journals (Sweden)

    Ming-Yuan Ren

    2014-03-01

    Full Text Available Conventional methods for rotor position detection of micro-gyroscopes include common exciting electrodes (single frequency and common sensing electrodes (frequency multiplex, but they have encountered some problems. So we present a high resolution and low noise pick-off circuit for micro-gyroscopes which utilizes the time multiplex method. The detecting circuit adopts a continuous-time current sensing circuit for capacitance measurement, and its noise analysis of the charge amplifier is introduced. The equivalent output noise power spectral density of phase-sensitive demodulation is 120 nV/Hz1/2. Tests revealed that the whole circuitry has a relative capacitance resolution of 1 × 10−8.

  17. DETECTION OF BARCHAN DUNES IN HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    M. A. Azzaoui

    2016-06-01

    Full Text Available Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction filters. Then, the second step proceeds to eliminate the parts of the image having a texture different from that of the barchans dunes. Using supervised learning, we tested a coarse to fine textural analysis based on Kolomogorov Smirnov test and Youden’s J-statistic on co-occurrence matrix. As an output we obtained a mask that we used in the next step to reduce the search area. In the third step we used a gliding window on the mask and check SURF features with SVM to get barchans dunes candidates. Detected barchans dunes were considered as the fusion of overlapping candidates. The results of this approach were very satisfying in processing time and precision.

  18. Development of a high-throughput microfluidic integrated microarray for the detection of chimeric bioweapons.

    Energy Technology Data Exchange (ETDEWEB)

    Sheppod, Timothy; Satterfield, Brent; Hukari, Kyle W.; West, Jason A. A.; Hux, Gary A.

    2006-10-01

    The advancement of DNA cloning has significantly augmented the potential threat of a focused bioweapon assault, such as a terrorist attack. With current DNA cloning techniques, toxin genes from the most dangerous (but environmentally labile) bacterial or viral organism can now be selected and inserted into robust organism to produce an infinite number of deadly chimeric bioweapons. In order to neutralize such a threat, accurate detection of the expressed toxin genes, rather than classification on strain or genealogical decent of these organisms, is critical. The development of a high-throughput microarray approach will enable the detection of unknowns chimeric bioweapons. The development of a high-throughput microarray approach will enable the detection of unknown bioweapons. We have developed a unique microfluidic approach to capture and concentrate these threat genes (mRNA's) upto a 30 fold concentration. These captured oligonucleotides can then be used to synthesize in situ oligonucleotide copies (cDNA probes) of the captured genes. An integrated microfluidic architecture will enable us to control flows of reagents, perform clean-up steps and finally elute nanoliter volumes of synthesized oligonucleotides probes. The integrated approach has enabled a process where chimeric or conventional bioweapons can rapidly be identified based on their toxic function, rather than being restricted to information that may not identify the critical nature of the threat.

  19. Automated High-Speed Video Detection of Small-Scale Explosives Testing

    Science.gov (United States)

    Ford, Robert; Guymon, Clint

    2013-06-01

    Small-scale explosives sensitivity test data is used to evaluate hazards of processing, handling, transportation, and storage of energetic materials. Accurate test data is critical to implementation of engineering and administrative controls for personnel safety and asset protection. Operator mischaracterization of reactions during testing contributes to either excessive or inadequate safety protocols. Use of equipment and associated algorithms to aid the operator in reaction determination can significantly reduce operator error. Safety Management Services, Inc. has developed an algorithm to evaluate high-speed video images of sparks from an ESD (Electrostatic Discharge) machine to automatically determine whether or not a reaction has taken place. The algorithm with the high-speed camera is termed GoDetect (patent pending). An operator assisted version for friction and impact testing has also been developed where software is used to quickly process and store video of sensitivity testing. We have used this method for sensitivity testing with multiple pieces of equipment. We present the fundamentals of GoDetect and compare it to other methods used for reaction detection.

  20. Highly Sensitive Detection of UV Radiation Using a Uranium Coordination Polymer.

    Science.gov (United States)

    Liu, Wei; Dai, Xing; Xie, Jian; Silver, Mark A; Zhang, Duo; Wang, Yanlong; Cai, Yawen; Diwu, Juan; Wang, Jian; Zhou, Ruhong; Chai, Zhifang; Wang, Shuao

    2018-02-07

    The accurate detection of UV radiation is required in a wide range of chemical industries and environmental or biological related applications. Conventional methods taking advantage of semiconductor photodetectors suffer from several drawbacks such as sophisticated synthesis and manufacturing procedure, not being able to measure the accumulated UV dosage as well as high defect density in the material. Searching for new strategies or materials serving as precise UV dosage sensor with extremely low detection limit is still highly desirable. In this work, a radiation resistant uranium coordination polymer [UO 2 (L)(DMF)] (L = 5-nitroisophthalic acid, DMF = N,N-dimethylformamide, denoted as compound 1) was successfully synthesized through mild solvothermal method and investigated as a unique UV probe with the detection limit of 2.4 × 10 -7 J. On the basis of the UV dosage dependent luminescence spectra, EPR analysis, single crystal structure investigation, and the DFT calculation, the UV-induced radical quenching mechanism was confirmed. Importantly, the generated radicals are of significant stability which offers the opportunity for measuring the accumulated UV radiation dosage. Furthermore, the powder material of compound 1 was further upgraded into membrane material without loss in luminescence intensity to investigate the real application potentials. To the best of our knowledge, compound 1 represents the most sensitive coordination polymer based UV dosage probe reported to date.

  1. Accurate detection and quantification of the fish viral hemorrhagic Septicemia virus (VHSv with a two-color fluorometric real-time PCR assay.

    Directory of Open Access Journals (Sweden)

    Lindsey R Pierce

    Full Text Available Viral Hemorrhagic Septicemia virus (VHSv is one of the world's most serious fish pathogens, infecting >80 marine, freshwater, and estuarine fish species from Eurasia and North America. A novel and especially virulent strain - IVb - appeared in the Great Lakes in 2003, has killed many game fish species in a series of outbreaks in subsequent years, and shut down interstate transport of baitfish. Cell culture is the diagnostic method approved by the USDA-APHIS, which takes a month or longer, lacks sensitivity, and does not quantify the amount of virus. We thus present a novel, easy, rapid, and highly sensitive real-time quantitative reverse transcription PCR (qRT-PCR assay that incorporates synthetic competitive template internal standards for quality control to circumvent false negative results. Results demonstrate high signal-to-analyte response (slope = 1.00±0.02 and a linear dynamic range that spans seven orders of magnitude (R(2 = 0.99, ranging from 6 to 6,000,000 molecules. Infected fishes are found to harbor levels of virus that range to 1,200,000 VHSv molecules/10(6 actb1 molecules with 1,000 being a rough cut-off for clinical signs of disease. This new assay is rapid, inexpensive, and has significantly greater accuracy than other published qRT-PCR tests and traditional cell culture diagnostics.

  2. Accurate detection and quantification of the fish viral hemorrhagic Septicemia virus (VHSv) with a two-color fluorometric real-time PCR assay.

    Science.gov (United States)

    Pierce, Lindsey R; Willey, James C; Palsule, Vrushalee V; Yeo, Jiyoun; Shepherd, Brian S; Crawford, Erin L; Stepien, Carol A

    2013-01-01

    Viral Hemorrhagic Septicemia virus (VHSv) is one of the world's most serious fish pathogens, infecting >80 marine, freshwater, and estuarine fish species from Eurasia and North America. A novel and especially virulent strain - IVb - appeared in the Great Lakes in 2003, has killed many game fish species in a series of outbreaks in subsequent years, and shut down interstate transport of baitfish. Cell culture is the diagnostic method approved by the USDA-APHIS, which takes a month or longer, lacks sensitivity, and does not quantify the amount of virus. We thus present a novel, easy, rapid, and highly sensitive real-time quantitative reverse transcription PCR (qRT-PCR) assay that incorporates synthetic competitive template internal standards for quality control to circumvent false negative results. Results demonstrate high signal-to-analyte response (slope = 1.00±0.02) and a linear dynamic range that spans seven orders of magnitude (R(2) = 0.99), ranging from 6 to 6,000,000 molecules. Infected fishes are found to harbor levels of virus that range to 1,200,000 VHSv molecules/10(6) actb1 molecules with 1,000 being a rough cut-off for clinical signs of disease. This new assay is rapid, inexpensive, and has significantly greater accuracy than other published qRT-PCR tests and traditional cell culture diagnostics.

  3. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Makoto [Iwate Medical University, Department of Radiology, Morioka (Japan); Honda, Satoshi [St. Luke' s International Hospital, Department of Radiology, Tokyo (Japan); Yuasa, Tatsuhiko; Iwamura, Akihide [Kohnodai Hospital, National Center of Neurology and Psychiatry, Department of Neurology, Ichikawa (Japan); Shibata, Eri [Iwate Medical University, Department of Neuropsychiatry, Morioka (Japan); Ohba, Hideki [Iwate Medical University, Department of Neurology, Morioka (Japan)

    2008-02-15

    The aim of this study was to determine the performance of axial and coronal magnetic resonance imaging (MRI) in detecting the narrowing of the cerebrospinal fluid (CSF) space at the high convexity and high midline areas, which is speculated to be one of the clinical characteristics of idiopathic normal pressure hydrocephalus (iNPH). We retrospectively examined axial and coronal T1-weighted images of 14 iNPH patients and 12 age-matched controls. The narrowness of the CSF space at the high convexity/midline was blindly evaluated by five raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. Axial and coronal imaging accurately determined the presence of the narrow cisterns/sulci at the high convexity/midline and was capable of predicting probable/definite iNPH with a high degree of accuracy. there were also no significant differences in the detection of this finding between the axial and coronal images. Both axial and coronal T1-weighted MRI can detect the narrow CSF space at the high convexity/midline accurately and may therefore facilitate clinicians in choosing a management strategy for iNPH patients. (orig.)

  4. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI

    International Nuclear Information System (INIS)

    Sasaki, Makoto; Honda, Satoshi; Yuasa, Tatsuhiko; Iwamura, Akihide; Shibata, Eri; Ohba, Hideki

    2008-01-01

    The aim of this study was to determine the performance of axial and coronal magnetic resonance imaging (MRI) in detecting the narrowing of the cerebrospinal fluid (CSF) space at the high convexity and high midline areas, which is speculated to be one of the clinical characteristics of idiopathic normal pressure hydrocephalus (iNPH). We retrospectively examined axial and coronal T1-weighted images of 14 iNPH patients and 12 age-matched controls. The narrowness of the CSF space at the high convexity/midline was blindly evaluated by five raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. Axial and coronal imaging accurately determined the presence of the narrow cisterns/sulci at the high convexity/midline and was capable of predicting probable/definite iNPH with a high degree of accuracy. there were also no significant differences in the detection of this finding between the axial and coronal images. Both axial and coronal T1-weighted MRI can detect the narrow CSF space at the high convexity/midline accurately and may therefore facilitate clinicians in choosing a management strategy for iNPH patients. (orig.)

  5. Optoelectronic properties of XIn2S4 (X = Cd, Mg) thiospinels through highly accurate all-electron FP-LAPW method coupled with modified approximations

    International Nuclear Information System (INIS)

    Yousaf, Masood; Dalhatu, S.A.; Murtaza, G.; Khenata, R.; Sajjad, M.; Musa, A.; Rahnamaye Aliabad, H.A.; Saeed, M.A.

    2015-01-01

    Highlights: • Highly accurate all-electron FP-LAPW+lo method is used. • New physical parameters are reported, important for the fabrication of optoelectronic devices. • A comparative study that involves FP-LAPW+lo method and modified approximations. • Computed band gap values have good agreement with the experimental values. • Optoelectronic results of fundamental importance can be utilized for the fabrication of devices. - Abstract: We report the structural, electronic and optical properties of the thiospinels XIn 2 S 4 (X = Cd, Mg), using highly accurate all-electron full potential linearized augmented plane wave plus local orbital method. In order to calculate the exchange and correlation energies, the method is coupled with modified techniques such as GGA+U and mBJ-GGA, which yield improved results as compared to the previous studies. GGA+SOC approximation is also used for the first time on these compounds to examine the spin orbit coupling effect on the band structure. From the analysis of the structural parameters, robust character is predicted for both materials. Energy band structures profiles are fairly the same for GGA, GGA+SOC, GGA+U and mBJ-GGA, confirming the indirect and direct band gap nature of CdIn 2 S 4 and MgIn 2 S 4 materials, respectively. We report the trend of band gap results as: (mBJ-GGA) > (GGA+U) > (GGA) > (GGA+SOC). Localized regions appearing in the valence bands for CdIn 2 S 4 tend to split up nearly by ≈1 eV in the case of GGA+SOC. Many new physical parameters are reported that can be important for the fabrication of optoelectronic devices. Optical spectra namely, dielectric function (DF), refractive index n(ω), extinction coefficient k(ω), reflectivity R(ω), optical conductivity σ(ω), absorption coefficient α(ω) and electron loss function are discussed. Optical’s absorption edge is noted to be 1.401 and 1.782 for CdIn 2 S 4 and MgIn 2 S 4 , respectively. The prominent peaks in the electron energy spectrum

  6. REDItools: high-throughput RNA editing detection made easy.

    Science.gov (United States)

    Picardi, Ernesto; Pesole, Graziano

    2013-07-15

    The reliable detection of RNA editing sites from massive sequencing data remains challenging and, although several methodologies have been proposed, no computational tools have been released to date. Here, we introduce REDItools a suite of python scripts to perform high-throughput investigation of RNA editing using next-generation sequencing data. REDItools are in python programming language and freely available at http://code.google.com/p/reditools/. ernesto.picardi@uniba.it or graziano.pesole@uniba.it Supplementary data are available at Bioinformatics online.

  7. Cloud detection method for Chinese moderate high resolution satellite imagery (Conference Presentation)

    Science.gov (United States)

    Zhong, Bo; Chen, Wuhan; Wu, Shanlong; Liu, Qinhuo

    2016-10-01

    Cloud detection of satellite imagery is very important for quantitative remote sensing research and remote sensing applications. However, many satellite sensors don't have enough bands for a quick, accurate, and simple detection of clouds. Particularly, the newly launched moderate to high spatial resolution satellite sensors of China, such as the charge-coupled device on-board the Chinese Huan Jing 1 (HJ-1/CCD) and the wide field of view (WFV) sensor on-board the Gao Fen 1 (GF-1), only have four available bands including blue, green, red, and near infrared bands, which are far from the requirements of most could detection methods. In order to solve this problem, an improved and automated cloud detection method for Chinese satellite sensors called OCM (Object oriented Cloud and cloud-shadow Matching method) is presented in this paper. It firstly modified the Automatic Cloud Cover Assessment (ACCA) method, which was developed for Landsat-7 data, to get an initial cloud map. The modified ACCA method is mainly based on threshold and different threshold setting produces different cloud map. Subsequently, a strict threshold is used to produce a cloud map with high confidence and large amount of cloud omission and a loose threshold is used to produce a cloud map with low confidence and large amount of commission. Secondly, a corresponding cloud-shadow map is also produced using the threshold of near-infrared band. Thirdly, the cloud maps and cloud-shadow map are transferred to cloud objects and cloud-shadow objects. Cloud and cloud-shadow are usually in pairs; consequently, the final cloud and cloud-shadow maps are made based on the relationship between cloud and cloud-shadow objects. OCM method was tested using almost 200 HJ-1/CCD images across China and the overall accuracy of cloud detection is close to 90%.

  8. AMS detection of actinides at high mass separation

    Energy Technology Data Exchange (ETDEWEB)

    Steier, Peter; Lachner, Johannes; Priller, Alfred; Winkler, Stephan; Golser, Robin [University of Vienna, Faculty of Physics, Vienna (Austria); Eigl, Rosmarie [Hiroshima University, Earth and Planetary Systems Science, Hiroshima (Japan); Quinto, Francesca [Institut fuer Nukleare Entsorgung, KIT, Eggenstein-Leopoldshafen (Germany); Sakaguchi, Aya [University of Tsukuba, Center for Research in Isotopes and Environmental Dynamics, Tsukuba (Japan)

    2015-07-01

    AMS is the mass spectrometric method with the highest abundance sensitivity, which is a prerequisite for measurement of the long-lived radioisotope {sup 236}U (t{sub 1/2}=23.4 million years). The most successful application so far is oceanography, since anthropogenic {sup 236}U is present in the world oceans at {sup 236}U:{sup 238}U from 10{sup -11} to 10{sup -8}. We have explored methods to increase the sensitivity and thus to reduce the water volume required to 1 L or less, which significantly reduces the sampling effort. High sensitivity is also necessary to address the expected typical natural isotopic ratios on the order {sup 236}U:{sup 238}U = 10{sup -13}, with potential applications in geology. With a second 90 analyzer magnet and a new Time-of-Flight beam line, VERA is robust against chemical impurities in the background, which e.g. allows measuring Pu isotopes directly in a uranium matrix. This simplifies chemical sample preparation for actinide detection, and may illustrate why AMS reaches lower detection limits than other mass spectrometric methods with nominally higher detection efficiency.

  9. CEST ANALYSIS: AUTOMATED CHANGE DETECTION FROM VERY-HIGH-RESOLUTION REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    M. Ehlers

    2012-08-01

    Full Text Available A fast detection, visualization and assessment of change in areas of crisis or catastrophes are important requirements for coordination and planning of help. Through the availability of new satellites and/or airborne sensors with very high spatial resolutions (e.g., WorldView, GeoEye new remote sensing data are available for a better detection, delineation and visualization of change. For automated change detection, a large number of algorithms has been proposed and developed. From previous studies, however, it is evident that to-date no single algorithm has the potential for being a reliable change detector for all possible scenarios. This paper introduces the Combined Edge Segment Texture (CEST analysis, a decision-tree based cooperative suite of algorithms for automated change detection that is especially designed for the generation of new satellites with very high spatial resolution. The method incorporates frequency based filtering, texture analysis, and image segmentation techniques. For the frequency analysis, different band pass filters can be applied to identify the relevant frequency information for change detection. After transforming the multitemporal images via a fast Fourier transform (FFT and applying the most suitable band pass filter, different methods are available to extract changed structures: differencing and correlation in the frequency domain and correlation and edge detection in the spatial domain. Best results are obtained using edge extraction. For the texture analysis, different 'Haralick' parameters can be calculated (e.g., energy, correlation, contrast, inverse distance moment with 'energy' so far providing the most accurate results. These algorithms are combined with a prior segmentation of the image data as well as with morphological operations for a final binary change result. A rule-based combination (CEST of the change algorithms is applied to calculate the probability of change for a particular location. CEST

  10. FY1995 study of the development of high resolution sub-surface fluid monitoring system using accurately controlled routine operated seismic system; 1995 nendo seimitsu seigyo shingen ni yoru chika ryutai koseido monitoring no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The development of new seismic sounding system based on the new concept of ACROSS (Accurately Controlled Routine-Operated Signal System) are aimed. The system includes not only new seismic sources but also the analyzing software specialize for the monitoring of the change in subsurface velocity structure, especially in the area of fluid resources. Powerful sources with good portability are strongly required for the practical data acquisition. Portable ACROSS sources (HIT) are developed. The system is mainly used to obtain the high resolution structure with relatively short penetration distance. The principal specifications are as follows: (1) 100Hz in maximum. (2) Linearly oscillating single force. This is generated by the combined two rotator moving opposite directions. (3) Variable force with little work. (4) Very simple source-ground coupler just put even on the soft ground. The system was operated at Yamagawa geothermal plant for two months. The result of the experiments are: (1) We confirmed the stability of the source over wide frequency range up to 100Hz. (2) We confirmed that amplitude and phase of ACROSS signal can be obtained very precisely. (3) Very small change of signal which arise from subsurface velocity change are detected. This indicates that the system can detect the slight velocity change due to variation of subsurface fluid system. (NEDO)

  11. Accurate Measurement of the Optical Constants n and k for a Series of 57 Inorganic and Organic Liquids for Optical Modeling and Detection.

    Science.gov (United States)

    Myers, Tanya L; Tonkyn, Russell G; Danby, Tyler O; Taubman, Matthew S; Bernacki, Bruce E; Birnbaum, Jerome C; Sharpe, Steven W; Johnson, Timothy J

    2018-04-01

    For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties that include chemical structure, optical band strength, volatility, and viscosity. By obtaining the optical constants, one can model most optical phenomena in media and at interfaces including reflection, refraction, and dispersion. Based on the works of others, we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organic, and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for dimethyl methylphosphonate (DMMP) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.

  12. Rapid and Accurate Detection of Bacteriophage Activity against Escherichia coli O157:H7 by Propidium Monoazide Real-Time PCR

    Directory of Open Access Journals (Sweden)

    Hui Liu

    2014-01-01

    Full Text Available Conventional methods to determine the efficacy of bacteriophage (phage for biocontrol of E. coli require several days, due to the need to culture bacteria. Furthermore, cell surface-attached phage particles may lyse bacterial cells during experiments, leading to an overestimation of phage activity. DNA-based real-time quantitative polymerase chain reaction (qPCR is a fast, sensitive, and highly specific means of enumerating pathogens. However, qPCR may underestimate phage activity due to its inability to distinguish viable from nonviable cells. In this study, we evaluated the suitability of propidium monoazide (PMA, a microbial membrane-impermeable dye that inhibits amplification of extracellular DNA and DNA within dead or membrane-compromised cells as a means of using qPCR to identify only intact E. coli cells that survive phage exposure. Escherichia coli O157:H7 strain R508N and 4 phages (T5-like, T1-like, T4-like, and O1-like were studied. Results compared PMA-qPCR and direct plating and confirmed that PMA could successfully inhibit amplification of DNA from compromised/damaged cells E. coli O157:H7. Compared to PMA-qPCR, direct plating overestimated (P < 0.01 phage efficacy as cell surface-attached phage particles lysed E. coli O157:H7 during the plating process. Treatment of samples with PMA in combination with qPCR can therefore be considered beneficial when assessing the efficacy of bacteriophage for biocontrol of E. coli O157:H7.

  13. Feasibility study for application of the compressed-sensing framework to interior computed tomography (ICT) for low-dose, high-accurate dental x-ray imaging

    Science.gov (United States)

    Je, U. K.; Cho, H. M.; Cho, H. S.; Park, Y. O.; Park, C. K.; Lim, H. W.; Kim, K. S.; Kim, G. A.; Park, S. Y.; Woo, T. H.; Choi, S. I.

    2016-02-01

    In this paper, we propose a new/next-generation type of CT examinations, the so-called Interior Computed Tomography (ICT), which may presumably lead to dose reduction to the patient outside the target region-of-interest (ROI), in dental x-ray imaging. Here an x-ray beam from each projection position covers only a relatively small ROI containing a target of diagnosis from the examined structure, leading to imaging benefits such as decreasing scatters and system cost as well as reducing imaging dose. We considered the compressed-sensing (CS) framework, rather than common filtered-backprojection (FBP)-based algorithms, for more accurate ICT reconstruction. We implemented a CS-based ICT algorithm and performed a systematic simulation to investigate the imaging characteristics. Simulation conditions of two ROI ratios of 0.28 and 0.14 between the target and the whole phantom sizes and four projection numbers of 360, 180, 90, and 45 were tested. We successfully reconstructed ICT images of substantially high image quality by using the CS framework even with few-view projection data, still preserving sharp edges in the images.

  14. Precision Timing of PSR J0437-4715: An Accurate Pulsar Distance, a High Pulsar Mass, and a Limit on the Variation of Newton's Gravitational Constant

    Science.gov (United States)

    Verbiest, J. P. W.; Bailes, M.; van Straten, W.; Hobbs, G. B.; Edwards, R. T.; Manchester, R. N.; Bhat, N. D. R.; Sarkissian, J. M.; Jacoby, B. A.; Kulkarni, S. R.

    2008-05-01

    Analysis of 10 years of high-precision timing data on the millisecond pulsar PSR J0437-4715 has resulted in a model-independent kinematic distance based on an apparent orbital period derivative, dot Pb , determined at the 1.5% level of precision (Dk = 157.0 +/- 2.4 pc), making it one of the most accurate stellar distance estimates published to date. The discrepancy between this measurement and a previously published parallax distance estimate is attributed to errors in the DE200 solar system ephemerides. The precise measurement of dot Pb allows a limit on the variation of Newton's gravitational constant, |Ġ/G| <= 23 × 10-12 yr-1. We also constrain any anomalous acceleration along the line of sight to the pulsar to |a⊙/c| <= 1.5 × 10-18 s-1 at 95% confidence, and derive a pulsar mass, mpsr = 1.76 +/- 0.20 M⊙, one of the highest estimates so far obtained.

  15. Automated Detection of Thermo-Erosion in High Latitude Ecosystems

    Science.gov (United States)

    Lara, M. J.; Chipman, M. L.; Hu, F.

    2017-12-01

    Detecting permafrost disturbance is of critical importance as the severity of climate change and associated increase in wildfire frequency and magnitude impacts regional to global carbon dynamics. However, it has not been possible to evaluate spatiotemporal patterns of permafrost degradation over large regions of the Arctic, due to limited spatial and temporal coverage of high resolution optical, radar, lidar, or hyperspectral remote sensing products. Here we present the first automated multi-temporal analysis for detecting disturbance in response to permafrost thaw, using meso-scale high-frequency remote sensing products (i.e. entire Landsat image archive). This approach was developed, tested, and applied in the Noatak National Preserve (26,500km2) in northwestern Alaska. We identified thermo-erosion (TE), by capturing the indirect spectral signal associated with episodic sediment plumes in adjacent waterbodies following TE disturbance. We isolated this turbidity signal within lakes during summer (mid-summer & late-summer) and annual time-period image composites (1986-2016), using the cloud-based geospatial parallel processing platform, Google Earth Engine™API. We validated the TE detection algorithm using seven consecutive years of sub-meter high resolution imagery (2009-2015) covering 798 ( 33%) of the 2456 total lakes in the Noatak lowlands. Our approach had "good agreement" with sediment pulses and landscape deformation in response to permafrost thaw (overall accuracy and kappa coefficient of 85% and 0.61). We identify active TE to impact 10.4% of all lakes, but was inter-annually variable, with the highest and lowest TE years represented by 1986 ( 41.1%) and 2002 ( 0.7%), respectively. We estimate thaw slumps, lake erosion, lake drainage, and gully formation to account for 23.3, 61.8, 12.5, and 1.3%, of all active TE across the Noatak National Preserve. Preliminary analysis, suggests TE may be subject to a hysteresis effect following extreme climatic

  16. A non-rigid point matching method with local topology preservation for accurate bladder dose summation in high dose rate cervical brachytherapy

    International Nuclear Information System (INIS)

    Chen, Haibin; Liao, Yuliang; Zhen, Xin; Zhou, Linghong; Zhong, Zichun; Pompoš, Arnold; Hrycushko, Brian; Albuquerque, Kevin; Gu, Xuejun

    2016-01-01

    GEC-ESTRO guidelines for high dose rate cervical brachytherapy advocate the reporting of the D2cc (the minimum dose received by the maximally exposed 2cc volume) to organs at risk. Due to large interfractional organ motion, reporting of accurate cumulative D2cc over a multifractional course is a non-trivial task requiring deformable image registration and deformable dose summation. To efficiently and accurately describe the point-to-point correspondence of the bladder wall over all treatment fractions while preserving local topologies, we propose a novel graphic processing unit (GPU)-based non-rigid point matching algorithm. This is achieved by introducing local anatomic information into the iterative update of correspondence matrix computation in the ‘thin plate splines-robust point matching’ (TPS-RPM) scheme. The performance of the GPU-based TPS-RPM with local topology preservation algorithm (TPS-RPM-LTP) was evaluated using four numerically simulated synthetic bladders having known deformations, a custom-made porcine bladder phantom embedded with twenty one fiducial markers, and 29 fractional computed tomography (CT) images from seven cervical cancer patients. Results show that TPS-RPM-LTP achieved excellent geometric accuracy with landmark residual distance error (RDE) of 0.7  ±  0.3 mm for the numerical synthetic data with different scales of bladder deformation and structure complexity, and 3.7  ±  1.8 mm and 1.6  ±  0.8 mm for the porcine bladder phantom with large and small deformation, respectively. The RDE accuracy of the urethral orifice landmarks in patient bladders was 3.7  ±  2.1 mm. When compared to the original TPS-RPM, the TPS-RPM-LTP improved landmark matching by reducing landmark RDE by 50  ±  19%, 37  ±  11% and 28  ±  11% for the synthetic, porcine phantom and the patient bladders, respectively. This was achieved with a computational time of less than 15 s in all cases

  17. SNP Data Quality Control in a National Beef and Dairy Cattle System and Highly Accurate SNP Based Parentage Verification and Identification

    Directory of Open Access Journals (Sweden)

    Matthew C. McClure

    2018-03-01

    -matching genotypes per animal, SNP duplicates, sex and breed prediction mismatches, parentage and progeny validation results, and other situations. The Animal QC pipeline make use of ICBF800 SNP set where appropriate to identify errors in a computationally efficient yet still highly accurate method.

  18. A non-rigid point matching method with local topology preservation for accurate bladder dose summation in high dose rate cervical brachytherapy.

    Science.gov (United States)

    Chen, Haibin; Zhong, Zichun; Liao, Yuliang; Pompoš, Arnold; Hrycushko, Brian; Albuquerque, Kevin; Zhen, Xin; Zhou, Linghong; Gu, Xuejun

    2016-02-07

    GEC-ESTRO guidelines for high dose rate cervical brachytherapy advocate the reporting of the D2cc (the minimum dose received by the maximally exposed 2cc volume) to organs at risk. Due to large interfractional organ motion, reporting of accurate cumulative D2cc over a multifractional course is a non-trivial task requiring deformable image registration and deformable dose summation. To efficiently and accurately describe the point-to-point correspondence of the bladder wall over all treatment fractions while preserving local topologies, we propose a novel graphic processing unit (GPU)-based non-rigid point matching algorithm. This is achieved by introducing local anatomic information into the iterative update of correspondence matrix computation in the 'thin plate splines-robust point matching' (TPS-RPM) scheme. The performance of the GPU-based TPS-RPM with local topology preservation algorithm (TPS-RPM-LTP) was evaluated using four numerically simulated synthetic bladders having known deformations, a custom-made porcine bladder phantom embedded with twenty one fiducial markers, and 29 fractional computed tomography (CT) images from seven cervical cancer patients. Results show that TPS-RPM-LTP achieved excellent geometric accuracy with landmark residual distance error (RDE) of 0.7  ±  0.3 mm for the numerical synthetic data with different scales of bladder deformation and structure complexity, and 3.7  ±  1.8 mm and 1.6  ±  0.8 mm for the porcine bladder phantom with large and small deformation, respectively. The RDE accuracy of the urethral orifice landmarks in patient bladders was 3.7  ±  2.1 mm. When compared to the original TPS-RPM, the TPS-RPM-LTP improved landmark matching by reducing landmark RDE by 50  ±  19%, 37  ±  11% and 28  ±  11% for the synthetic, porcine phantom and the patient bladders, respectively. This was achieved with a computational time of less than 15 s in all cases

  19. High detection rate of dog circovirus in diarrheal dogs.

    Science.gov (United States)

    Hsu, Han-Siang; Lin, Ting-Han; Wu, Hung-Yi; Lin, Lee-Shuan; Chung, Cheng-Shu; Chiou, Ming-Tang; Lin, Chao-Nan

    2016-06-17

    Diarrhea is one of the most common clinical symptoms reported in companion animal clinics. Dog circovirus (DogCV) is a new mammalian circovirus that is considered to be a cause of alimentary syndromes such as diarrhea, vomiting and hemorrhagic enteritis. DogCV has previously only been identified in the United States, Italy, Germany (GeneBank accession number: KF887949) and China (GeneBank accession number: KT946839). Therefore, the aims of this study were to determine the prevalence of DogCV in Taiwan and to explore the correlation between diarrhea and DogCV infection. Clinical specimens were collected between 2012 and 2014 from 207 dogs suffering from diarrhea and 160 healthy dogs. In this study, we developed a sensitive and specific SYBR Green-based real-time PCR assays to detected DogCV in naturally infected animals. Of the analyzed fecal samples from diarrheal dogs and health dogs, 58 (28.0 %) and 19 (11.9 %), respectively, were DogCV positive. The difference in DogCV prevalence was highly significant (P = 0.0002755) in diarrheal dogs. This is the first study to reveal that DogCV is currently circulating in domestic dogs in Taiwan and to demonstrate its high detection rate in dogs with diarrhea.

  20. Real-time defect detection on highly reflective curved surfaces

    Science.gov (United States)

    Rosati, G.; Boschetti, G.; Biondi, A.; Rossi, A.

    2009-03-01

    This paper presents an automated defect detection system for coated plastic components for the automotive industry. This research activity came up as an evolution of a previous study which employed a non-flat mirror to illuminate and inspect high reflective curved surfaces. According to this method, the rays emitted from a light source are conveyed on the surface under investigation by means of a suitably curved mirror. After the reflection on the surface, the light rays are collected by a CCD camera, in which the coating defects appear as shadows of various shapes and dimensions. In this paper we present an evolution of the above-mentioned method, introducing a simplified mirror set-up in order to reduce the costs and the complexity of the defect detection system. In fact, a set of plane mirrors is employed instead of the curved one. Moreover, the inspection of multiple bend radius parts is investigated. A prototype of the machine vision system has been developed in order to test this simplified method. This device is made up of a light projector, a set of plane mirrors for light rays reflection, a conveyor belt for handling components, a CCD camera and a desktop PC which performs image acquisition and processing. Like in the previous system, the defects are identified as shadows inside a high brightness image. At the end of the paper, first experimental results are presented.

  1. [Simultaneous determination of four compounds in Sanjing Shuanghuanglian Oral Liquid by high performance liquid chromatography-diode array detection-electrochemical detection].

    Science.gov (United States)

    Liu, Lin; Suo, Zhirong; Zheng, Jianbin

    2006-05-01

    Chlorogenic acid, caffeic acid, baicalin and luteolin in Sanjing Shuanghuanglian Oral Liquid were simultaneously detected and identified using a high performance liquid chromatography coupled with diode array detection and electrochemical detection (HPLC-DAD-ECD). The separation was performed on a Zorbax SB-C18 column (150 mm x 4.6 mm i. d., 5.0 microm). The mobile phase consisted of (A) methanol and (B) methanol-water-acetic acid (50: 50: 1, v/v/v) using a linear gradient elution of 2%A-3%A at 0-3 min, 3%A-25%A at 3-15 min, 25%A-80%A at 15-20 min. The flow rate was 0.8 mL/min. The DAD detection was used at 275 nm. The ECD detection was done at 0.7 V. The column thermostat set at 30 degrees C. The limits of detection of the 4 compounds were 1 mg/L for chlorogenic acid, 0.2 mg/L for caffeic acid, 9 mg/L for baicalin, 7 mg/L for luteolin. The average recoveries were between 96.6%-99.6% with relative standard deviations (RSDs) of 2.5%-4.1%. The method is simple, rapid, reproducible and accurate. It can be used for the routine analysis of the four compounds in Shuanghuanglian Oral Liquid.

  2. High-throughput image analysis of tumor spheroids: a user-friendly software application to measure the size of spheroids automatically and accurately.

    Science.gov (United States)

    Chen, Wenjin; Wong, Chung; Vosburgh, Evan; Levine, Arnold J; Foran, David J; Xu, Eugenia Y

    2014-07-08

    The increasing number of applications of three-dimensional (3D) tumor spheroids as an in vitro model for drug discovery requires their adaptation to large-scale screening formats in every step of a drug screen, including large-scale image analysis. Currently there is no ready-to-use and free image analysis software to meet this large-scale format. Most existing methods involve manually drawing the length and width of the imaged 3D spheroids, which is a tedious and time-consuming process. This study presents a high-throughput image analysis software application - SpheroidSizer, which measures the major and minor axial length of the imaged 3D tumor spheroids automatically and accurately; calculates the volume of each individual 3D tumor spheroid; then outputs the results in two different forms in spreadsheets for easy manipulations in the subsequent data analysis. The main advantage of this software is its powerful image analysis application that is adapted for large numbers of images. It provides high-throughput computation and quality-control workflow. The estimated time to process 1,000 images is about 15 min on a minimally configured laptop, or around 1 min on a multi-core performance workstation. The graphical user interface (GUI) is also designed for easy quality control, and users can manually override the computer results. The key method used in this software is adapted from the active contour algorithm, also known as Snakes, which is especially suitable for images with uneven illumination and noisy background that often plagues automated imaging processing in high-throughput screens. The complimentary "Manual Initialize" and "Hand Draw" tools provide the flexibility to SpheroidSizer in dealing with various types of spheroids and diverse quality images. This high-throughput image analysis software remarkably reduces labor and speeds up the analysis process. Implementing this software is beneficial for 3D tumor spheroids to become a routine in vitro model

  3. Microcystin Detection Characteristics of Fluorescence Immunochromatography and High Performance Liquid Chromatography

    International Nuclear Information System (INIS)

    Pyo, Dong Jin; Park, Geun Young; Choi, Jong Chon; Oh, Chang Suk

    2005-01-01

    Different detection characteristics of fluorescence immunochromatography method and high performance liquid chromatography (HPLC) method for the analysis of cyanobacterial toxins were studied. In particular, low and high limits of detection, detection time and reproducibility and detectable microcystin species were compared when fluorescence immunochromatography method and high performance liquid chromatography method were applied for the detection of microcystin (MC), a cyclic peptide toxin of the freshwater cyanobacterium Microcystis aeruginosa. A Fluorescence immunochromatography assay system has the unique advantages of short detection time and low detection limit, and high performance liquid chromatography detection method has the strong advantage of individual quantifications of several species of microcystins

  4. Combination of Autoantibody Signature with PSA Level Enables a Highly Accurate Blood-Based Differentiation of Prostate Cancer Patients from Patients with Benign Prostatic Hyperplasia.

    Directory of Open Access Journals (Sweden)

    Petra Leidinger

    Full Text Available Although an increased level of the prostate-specific antigen can be an indication for prostate cancer, other reasons often lead to a high rate of false positive results. Therefore, an additional serological screening of autoantibodies in patients' sera could improve the detection of prostate cancer. We performed protein macroarray screening with sera from 49 prostate cancer patients, 70 patients with benign prostatic hyperplasia and 28 healthy controls and compared the autoimmune response in those groups. We were able to distinguish prostate cancer patients from normal controls with an accuracy of 83.2%, patients with benign prostatic hyperplasia from normal controls with an accuracy of 86.0% and prostate cancer patients from patients with benign prostatic hyperplasia with an accuracy of 70.3%. Combining seroreactivity pattern with a PSA level of higher than 4.0 ng/ml this classification could be improved to an accuracy of 84.1%. For selected proteins we were able to confirm the differential expression by using luminex on 84 samples. We provide a minimally invasive serological method to reduce false positive results in detection of prostate cancer and according to PSA screening to distinguish men with prostate cancer from men with benign prostatic hyperplasia.

  5. Object-Based Change Detection Using High-Resolution Remotely Sensed Data and GIS

    Science.gov (United States)

    Sofina, N.; Ehlers, M.

    2012-08-01

    High resolution remotely sensed images provide current, detailed, and accurate information for large areas of the earth surface which can be used for change detection analyses. Conventional methods of image processing permit detection of changes by comparing remotely sensed multitemporal images. However, for performing a successful analysis it is desirable to take images from the same sensor which should be acquired at the same time of season, at the same time of a day, and - for electro-optical sensors - in cloudless conditions. Thus, a change detection analysis could be problematic especially for sudden catastrophic events. A promising alternative is the use of vector-based maps containing information about the original urban layout which can be related to a single image obtained after the catastrophe. The paper describes a methodology for an object-based search of destroyed buildings as a consequence of a natural or man-made catastrophe (e.g., earthquakes, flooding, civil war). The analysis is based on remotely sensed and vector GIS data. It includes three main steps: (i) generation of features describing the state of buildings; (ii) classification of building conditions; and (iii) data import into a GIS. One of the proposed features is a newly developed 'Detected Part of Contour' (DPC). Additionally, several features based on the analysis of textural information corresponding to the investigated vector objects are calculated. The method is applied to remotely sensed images of areas that have been subjected to an earthquake. The results show the high reliability of the DPC feature as an indicator for change.

  6. Automated detection and labeling of high-density EEG electrodes from structural MR images

    Science.gov (United States)

    Marino, Marco; Liu, Quanying; Brem, Silvia; Wenderoth, Nicole; Mantini, Dante

    2016-10-01

    Objective. Accurate knowledge about the positions of electrodes in electroencephalography (EEG) is very important for precise source localizations. Direct detection of electrodes from magnetic resonance (MR) images is particularly interesting, as it is possible to avoid errors of co-registration between electrode and head coordinate systems. In this study, we propose an automated MR-based method for electrode detection and labeling, particularly tailored to high-density montages. Approach. Anatomical MR images were processed to create an electrode-enhanced image in individual space. Image processing included intensity non-uniformity correction, background noise and goggles artifact removal. Next, we defined a search volume around the head where electrode positions were detected. Electrodes were identified as local maxima in the search volume and registered to the Montreal Neurological Institute standard space using an affine transformation. This allowed the matching of the detected points with the specific EEG montage template, as well as their labeling. Matching and labeling were performed by the coherent point drift method. Our method was assessed on 8 MR images collected in subjects wearing a 256-channel EEG net, using the displacement with respect to manually selected electrodes as performance metric. Main results. Average displacement achieved by our method was significantly lower compared to alternative techniques, such as the photogrammetry technique. The maximum displacement was for more than 99% of the electrodes lower than 1 cm, which is typically considered an acceptable upper limit for errors in electrode positioning. Our method showed robustness and reliability, even in suboptimal conditions, such as in the case of net rotation, imprecisely gathered wires, electrode detachment from the head, and MR image ghosting. Significance. We showed that our method provides objective, repeatable and precise estimates of EEG electrode coordinates. We hope our work

  7. Polypyrrole–gold nanoparticle composites for highly sensitive DNA detection

    International Nuclear Information System (INIS)

    Spain, Elaine; Keyes, Tia E.; Forster, Robert J.

    2013-01-01

    DNA capture surfaces represent a powerful approach to developing highly sensitive sensors for identifying the cause of infection. Electrochemically deposited polypyrrole, PPy, films have been functionalized with electrodeposited gold nanoparticles to give a nanocomposite material, PPy–AuNP. Thiolated capture strand DNA, that is complementary to the sequence from the pathogen Staphylococcus aureus that causes mammary gland inflammation, was then immobilized onto the gold nanoparticles and any of the underlying gold electrode that is exposed. A probe strand, labelled with horse radish peroxidase, HRP, was then hybridized to the target. The concentration of the target was determined by measuring the current generated by reducing benzoquinone produced by the HRP label. Semi-log plots of the pathogen DNA concentration vs. faradaic current are linear from 150 pM to 1 μM and pM concentrations can be detected without the need for molecular, e.g., PCR or NASBA, amplification. The nanocomposite also exhibits excellent selectivity and single base mismatches in a 30 mer sequence can be detected

  8. Detecting geomorphic processes and change with high resolution topographic data

    Science.gov (United States)

    Mudd, Simon; Hurst, Martin; Grieve, Stuart; Clubb, Fiona; Milodowski, David; Attal, Mikael

    2016-04-01

    The first global topographic dataset was released in 1996, with 1 km grid spacing. It is astonishing that in only 20 years we now have access to tens of thousands of square kilometres of LiDAR data at point densities greater than 5 points per square meter. This data represents a treasure trove of information that our geomorphic predecessors could only dream of. But what are we to do with this data? Here we explore the potential of high resolution topographic data to dig deeper into geomorphic processes across a wider range of landscapes and using much larger spatial coverage than previously possible. We show how this data can be used to constrain sediment flux relationships using relief and hillslope length, and how this data can be used to detect landscape transience. We show how the nonlinear sediment flux law, proposed for upland, soil mantled landscapes by Roering et al. (1999) is consistent with a number of topographic tests. This flux law allows us to predict how landscapes will respond to tectonic forcing, and we show how these predictions can be used to detect erosion rate perturbations across a range of tectonic settings.

  9. Prediction of collision cross section and retention time for broad scope screening in gradient reversed-phase liquid chromatography-ion mobility-high resolution accurate mass spectrometry.

    Science.gov (United States)

    Mollerup, Christian Brinch; Mardal, Marie; Dalsgaard, Petur Weihe; Linnet, Kristian; Barron, Leon Patrick

    2018-03-23

    Exact mass, retention time (RT), and collision cross section (CCS) are used as identification parameters in liquid chromatography coupled to ion mobility high resolution accurate mass spectrometry (LC-IM-HRMS). Targeted screening analyses are now more flexible and can be expanded for suspect and non-targeted screening. These allow for tentative identification of new compounds, and in-silico predicted reference values are used for improving confidence and filtering false-positive identifications. In this work, predictions of both RT and CCS values are performed with machine learning using artificial neural networks (ANNs). Prediction was based on molecular descriptors, 827 RTs, and 357 CCS values from pharmaceuticals, drugs of abuse, and their metabolites. ANN models for the prediction of RT or CCS separately were examined, and the potential to predict both from a single model was investigated for the first time. The optimized combined RT-CCS model was a four-layered multi-layer perceptron ANN, and the 95th prediction error percentiles were within 2 min RT error and 5% relative CCS error for the external validation set (n = 36) and the full RT-CCS dataset (n = 357). 88.6% (n = 733) of predicted RTs were within 2 min error for the full dataset. Overall, when using 2 min RT error and 5% relative CCS error, 91.9% (n = 328) of compounds were retained, while 99.4% (n = 355) were retained when using at least one of these thresholds. This combined prediction approach can therefore be useful for rapid suspect/non-targeted screening involving HRMS, and will support current workflows. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Micro-crack detection in high-performance cementitious materials

    DEFF Research Database (Denmark)

    Lura, Pietro; Guang, Ye; Tanaka, Kyoji

    2005-01-01

    of high-performance cement pastes in silicone moulds that exert minimal external restraint. Cast-in steel rods with varying diameter internally restrain the autogenous shrinkage and lead to crack formation. Dimensions of the steel rods are chosen so that the size of this restraining inclusion resembles......-ray tomography, do not allow sufficient resolution of microcracks. A new technique presented in this paper allows detection of microcracks in cement paste while avoiding artefacts induced by unwanted restraint, drying or temperature variations. The technique consists in casting small circular cylindrical samples...... aggregate size. Gallium intrusion of the cracks and subsequent examination by electron probe micro analysis, EPMA, are used to identify the cracks. The gallium intrusion technique allows controllable impregnation of cracks in the cement paste. A distinct contrast between gallium and the surrounding material...

  11. Early detection of psychosis: finding those at clinical high risk.

    Science.gov (United States)

    Addington, Jean; Epstein, Irvin; Reynolds, Andrea; Furimsky, Ivana; Rudy, Laura; Mancini, Barbara; McMillan, Simone; Kirsopp, Diane; Zipursky, Robert B

    2008-08-01

    In early detection work, recruiting individuals who meet the prodromal criteria is difficult. The aim of this paper was to describe the development of a research clinic for individuals who appear to be at risk of developing a psychosis and the process for educating the community and obtaining referrals. The outcome of all referrals to the clinic over a 4-year period was examined. Following an ongoing education campaign that was over inclusive in order to aid recruitment, approximately 27% of all referrals met the criteria for being at clinical high risk of psychosis. We are seeing only a small proportion of those in the community who eventually go on to develop a psychotic illness. This raises two important issues, namely how to remedy the situation, and second, the impact of this on current research in terms of sampling bias and generalizability of research findings. © 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Asia Pty Ltd.

  12. High-speed detection of DNA translocation in nanopipettes

    Science.gov (United States)

    Fraccari, Raquel L.; Ciccarella, Pietro; Bahrami, Azadeh; Carminati, Marco; Ferrari, Giorgio; Albrecht, Tim

    2016-03-01

    We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface.We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface. Electronic supplementary information (ESI) available: Gel electrophoresis confirming lengths and purity of DNA samples, comparison between Axopatch 200B and custom-built setup, comprehensive low-noise amplifier characterization, representative I-V curves of nanopipettes used, typical scatter plots of τ vs. peak amplitude for the four LDNA's used, table of most probable τ values, a comparison between different fitting models for the DNA translocation time distribution, further details on the stochastic numerical simulation of the scaling statistics and the derivation of the extended

  13. Towards accurate emergency response behavior

    International Nuclear Information System (INIS)

    Sargent, T.O.

    1981-01-01

    Nuclear reactor operator emergency response behavior has persisted as a training problem through lack of information. The industry needs an accurate definition of operator behavior in adverse stress conditions, and training methods which will produce the desired behavior. Newly assembled information from fifty years of research into human behavior in both high and low stress provides a more accurate definition of appropriate operator response, and supports training methods which will produce the needed control room behavior. The research indicates that operator response in emergencies is divided into two modes, conditioned behavior and knowledge based behavior. Methods which assure accurate conditioned behavior, and provide for the recovery of knowledge based behavior, are described in detail

  14. Spectrally accurate contour dynamics

    International Nuclear Information System (INIS)

    Van Buskirk, R.D.; Marcus, P.S.

    1994-01-01

    We present an exponentially accurate boundary integral method for calculation the equilibria and dynamics of piece-wise constant distributions of potential vorticity. The method represents contours of potential vorticity as a spectral sum and solves the Biot-Savart equation for the velocity by spectrally evaluating a desingularized contour integral. We use the technique in both an initial-value code and a newton continuation method. Our methods are tested by comparing the numerical solutions with known analytic results, and it is shown that for the same amount of computational work our spectral methods are more accurate than other contour dynamics methods currently in use

  15. Subnanomole detection and quantitation of high specific activity 32P-nucleotides

    International Nuclear Information System (INIS)

    Coniglio, C.; Pappas, G.; Gill, W.J.; Kashdan, M.; Maniscalco, M.

    1991-01-01

    Microbore liquid chromatography utilizes conventional HPLC and ultraviolet detection principles to determine subnanomole mass quantities of biologically significant molecules. This system takes advantage of specifically designed microflow equipment to analyze ultraviolet absorbing species at the picomole range. 32P-labeled nucleotides are examples of compounds routinely used at picomole quantities that are extremely difficult to accurately quantify using standard mass measurement techniques. The procedure described in this paper has the capability of measuring nucleotides down to 10 pmol using commercially available microbore ultraviolet detection equipment. The technique can be used to accurately measure the specific activity of as little as 10 microCi of an aqueous 32P-nucleotide solution

  16. Low- and high-order accurate boundary conditions: From Stokes to Darcy porous flow modeled with standard and improved Brinkman lattice Boltzmann schemes

    International Nuclear Information System (INIS)

    Silva, Goncalo; Talon, Laurent; Ginzburg, Irina

    2017-01-01

    and FEM is thoroughly evaluated in three benchmark tests, which are run throughout three distinctive permeability regimes. The first configuration is a horizontal porous channel, studied with a symbolic approach, where we construct the exact solutions of FEM and BF/IBF with different boundary schemes. The second problem refers to an inclined porous channel flow, which brings in as new challenge the formation of spurious boundary layers in LBM; that is, numerical artefacts that arise due to a deficient accommodation of the bulk solution by the low-accurate boundary scheme. The third problem considers a porous flow past a periodic square array of solid cylinders, which intensifies the previous two tests with the simulation of a more complex flow pattern. The ensemble of numerical tests provides guidelines on the effect of grid resolution and the TRT free collision parameter over the accuracy and the quality of the velocity field, spanning from Stokes to Darcy permeability regimes. It is shown that, with the use of the high-order accurate boundary schemes, the simple, uniform-mesh-based TRT-LBM formulation can even surpass the accuracy of FEM employing hardworking body-fitted meshes.

  17. Low- and high-order accurate boundary conditions: From Stokes to Darcy porous flow modeled with standard and improved Brinkman lattice Boltzmann schemes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Goncalo, E-mail: goncalo.nuno.silva@gmail.com [Irstea, Antony Regional Centre, HBAN, 1 rue Pierre-Gilles de Gennes CS 10030, 92761 Antony cedex (France); Talon, Laurent, E-mail: talon@fast.u-psud.fr [CNRS (UMR 7608), Laboratoire FAST, Batiment 502, Campus University, 91405 Orsay (France); Ginzburg, Irina, E-mail: irina.ginzburg@irstea.fr [Irstea, Antony Regional Centre, HBAN, 1 rue Pierre-Gilles de Gennes CS 10030, 92761 Antony cedex (France)

    2017-04-15

    and FEM is thoroughly evaluated in three benchmark tests, which are run throughout three distinctive permeability regimes. The first configuration is a horizontal porous channel, studied with a symbolic approach, where we construct the exact solutions of FEM and BF/IBF with different boundary schemes. The second problem refers to an inclined porous channel flow, which brings in as new challenge the formation of spurious boundary layers in LBM; that is, numerical artefacts that arise due to a deficient accommodation of the bulk solution by the low-accurate boundary scheme. The third problem considers a porous flow past a periodic square array of solid cylinders, which intensifies the previous two tests with the simulation of a more complex flow pattern. The ensemble of numerical tests provides guidelines on the effect of grid resolution and the TRT free collision parameter over the accuracy and the quality of the velocity field, spanning from Stokes to Darcy permeability regimes. It is shown that, with the use of the high-order accurate boundary schemes, the simple, uniform-mesh-based TRT-LBM formulation can even surpass the accuracy of FEM employing hardworking body-fitted meshes.

  18. Low resolution scans can provide a sufficiently accurate, cost- and time-effective alternative to high resolution scans for 3D shape analyses

    Directory of Open Access Journals (Sweden)

    Ariel E. Marcy

    2018-06-01

    Full Text Available Background Advances in 3D shape capture technology have made powerful shape analyses, such as geometric morphometrics, more feasible. While the highly accurate micro-computed tomography (µCT scanners have been the “gold standard,” recent improvements in 3D surface scanners may make this technology a faster, portable, and cost-effective alternative. Several studies have already compared the two devices but all use relatively large specimens such as human crania. Here we perform shape analyses on Australia’s smallest rodent to test whether a 3D scanner produces similar results to a µCT scanner. Methods We captured 19 delicate mouse (Pseudomys delicatulus crania with a µCT scanner and a 3D scanner for geometric morphometrics. We ran multiple Procrustes ANOVAs to test how variation due to scan device compared to other sources such as biologically relevant variation and operator error. We quantified operator error as levels of variation and repeatability. Further, we tested if the two devices performed differently at classifying individuals based on sexual dimorphism. Finally, we inspected scatterplots of principal component analysis (PCA scores for non-random patterns. Results In all Procrustes ANOVAs, regardless of factors included, differences between individuals contributed the most to total variation. The PCA plots reflect this in how the individuals are dispersed. Including only the symmetric component of shape increased the biological signal relative to variation due to device and due to error. 3D scans showed a higher level of operator error as evidenced by a greater spread of their replicates on the PCA, a higher level of multivariate variation, and a lower repeatability score. However, the 3D scan and µCT scan datasets performed identically in classifying individuals based on intra-specific patterns of sexual dimorphism. Discussion Compared to µCT scans, we find that even low resolution 3D scans of very small specimens are

  19. Highly sensitive and selective detection of dopamine using one-pot synthesized highly photoluminescent silicon nanoparticles.

    Science.gov (United States)

    Zhang, Xiaodong; Chen, Xiaokai; Kai, Siqi; Wang, Hong-Yin; Yang, Jingjing; Wu, Fu-Gen; Chen, Zhan

    2015-03-17

    A simple and highly efficient method for dopamine (DA) detection using water-soluble silicon nanoparticles (SiNPs) was reported. The SiNPs with a high quantum yield of 23.6% were synthesized by using a one-pot microwave-assisted method. The fluorescence quenching capability of a variety of molecules on the synthesized SiNPs has been tested; only DA molecules were found to be able to quench the fluorescence of these SiNPs effectively. Therefore, such a quenching effect can be used to selectively detect DA. All other molecules tested have little interference with the dopamine detection, including ascorbic acid, which commonly exists in cells and can possibly affect the dopamine detection. The ratio of the fluorescence intensity difference between the quenched and unquenched cases versus the fluorescence intensity without quenching (ΔI/I) was observed to be linearly proportional to the DA analyte concentration in the range from 0.005 to 10.0 μM, with a detection limit of 0.3 nM (S/N = 3). To the best of our knowledge, this is the lowest limit for DA detection reported so far. The mechanism of fluorescence quenching is attributed to the energy transfer from the SiNPs to the oxidized dopamine molecules through Förster resonance energy transfer. The reported method of SiNP synthesis is very simple and cheap, making the above sensitive and selective DA detection approach using SiNPs practical for many applications.

  20. Long distance high power optical laser fiber break detection and continuity monitoring systems and methods

    Science.gov (United States)

    Rinzler, Charles C.; Gray, William C.; Faircloth, Brian O.; Zediker, Mark S.

    2016-02-23

    A monitoring and detection system for use on high power laser systems, long distance high power laser systems and tools for performing high power laser operations. In particular, the monitoring and detection systems provide break detection and continuity protection for performing high power laser operations on, and in, remote and difficult to access locations.

  1. High-temperature superconducting nanowires for photon detection

    Energy Technology Data Exchange (ETDEWEB)

    Arpaia, R. [Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, S-41296 Göteborg (Sweden); CNR SPIN Institute – Superconductors, Innovative Materials and Devices, UOS–Napoli, I-80100 Napoli (Italy); Dipartimento di Fisica, Università degli Studi di Napoli ‘Federico II’, I-80125 Napoli (Italy); Ejrnaes, M. [CNR SPIN Institute – Superconductors, Innovative Materials and Devices, UOS–Napoli, I-80100 Napoli (Italy); Parlato, L. [CNR SPIN Institute – Superconductors, Innovative Materials and Devices, UOS–Napoli, I-80100 Napoli (Italy); Dipartimento di Fisica, Università degli Studi di Napoli ‘Federico II’, I-80125 Napoli (Italy); Tafuri, F. [CNR SPIN Institute – Superconductors, Innovative Materials and Devices, UOS–Napoli, I-80100 Napoli (Italy); Dipartimento di Ingegneria Industriale e dell’Informazione, Seconda Università di Napoli, I-81031 Aversa, CE (Italy); Cristiano, R. [CNR SPIN Institute – Superconductors, Innovative Materials and Devices, UOS–Napoli, I-80100 Napoli (Italy); Golubev, D. [Low Temperature Laboratory (OVLL), Aalto University School of Science, P.O. Box 13500, FI-00076 Aalto (Finland); Sobolewski, Roman, E-mail: roman.sobolewski@rochester.edu [Institute of Electron Technology, PL-02668 Warszawa (Poland); Department of Electrical and Computer Engineering and Laboratory for Laser Energetics, University of Rochester, NY 14627-0231 (United States); Bauch, T.; Lombardi, F. [Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, S-41296 Göteborg (Sweden); and others

    2015-02-15

    Highlights: • Homogeneous YBCO nanowires have been fabricated for photon detection applications. • Serial-parallel nanowire configuration leads to a large detector active area. • The YBCO nanowires exhibit critical current densities up to 106 A/cm{sup 2}. • The devices have been excited using a 1550-nm wavelength, pulsed laser irradiation. • Photoresponse signals have been measured and analyzed from 4 K up to the device T{sub c}. - Abstract: The possible use of high-temperature superconductors (HTS) for realizing superconducting nanowire single-photon detectors is a challenging, but also promising, aim because of their ultrafast electron relaxation times and high operating temperatures. The state-of-the-art HTS nanowires with a 50-nm thickness and widths down to 130 nm have been fabricated and tested under a 1550-nm wavelength laser irradiation. Experimental results presenting both the amplitude and rise times of the photoresponse signals as a function of the normalized detector bias current, measured in a wide temperature range, are discussed. The presence of two distinct regimes in the photoresponse temperature dependence is clearly evidenced, indicating that there are two different response mechanisms responsible for the HTS photoresponse mechanisms.

  2. High-Precision Dispensing of Nanoliter Biofluids on Glass Pedestal Arrays for Ultrasensitive Biomolecule Detection.

    Science.gov (United States)

    Chen, Xiaoxiao; Liu, Yang; Xu, QianFeng; Zhu, Jing; Poget, Sébastien F; Lyons, Alan M

    2016-05-04

    Precise dispensing of nanoliter droplets is necessary for the development of sensitive and accurate assays, especially when the availability of the source solution is limited. Conventional approaches are limited by imprecise positioning, large shear forces, surface tension effects, and high costs. To address the need for precise and economical dispensing of nanoliter volumes, we developed a new approach where the dispensed volume is dependent on the size and shape of defined surface features, thus freeing the dispensing process from pumps and fine-gauge needles requiring accurate positioning. The surface we fabricated, called a nanoliter droplet virtual well microplate (nVWP), achieves high-precision dispensing (better than ±0.5 nL or ±1.6% at 32 nL) of 20-40 nL droplets using a small source drop (3-10 μL) on isolated hydrophilic glass pedestals (500 μm on a side) bonded to arrays of polydimethylsiloxane conical posts. The sharp 90° edge of the glass pedestal pins the solid-liquid-vapor triple contact line (TCL), averting the wetting of the glass sidewalls while the fluid is prevented from receding from the edge. This edge creates a sufficiently large energy barrier such that microliter water droplets can be poised on the glass pedestals, exhibiting contact angles greater >150°. This approach relieves the stringent mechanical alignment tolerances required for conventional dispensing techniques, shifting the control of dispensed volume to the area circumscribed by the glass edge. The effects of glass surface chemistry and dispense velocity on droplet volume were studied using optical microscopy and high-speed video. Functionalization of the glass pedestal surface enabled the selective adsorption of specific peptides and proteins from synthetic and natural biomolecule mixtures, such as venom. We further demonstrate how the nVWP dispensing platform can be used for a variety of assays, including sensitive detection of proteins and peptides by fluorescence

  3. DNA barcode detects high genetic structure within neotropical bird species.

    Directory of Open Access Journals (Sweden)

    Erika Sendra Tavares

    Full Text Available BACKGROUND: Towards lower latitudes the number of recognized species is not only higher, but also phylogeographic subdivision within species is more pronounced. Moreover, new genetically isolated populations are often described in recent phylogenies of Neotropical birds suggesting that the number of species in the region is underestimated. Previous COI barcoding of Argentinean bird species showed more complex patterns of regional divergence in the Neotropical than in the North American avifauna. METHODS AND FINDINGS: Here we analyzed 1,431 samples from 561 different species to extend the Neotropical bird barcode survey to lower latitudes, and detected even higher geographic structure within species than reported previously. About 93% (520 of the species were identified correctly from their DNA barcodes. The remaining 41 species were not monophyletic in their COI sequences because they shared barcode sequences with closely related species (N = 21 or contained very divergent clusters suggestive of putative new species embedded within the gene tree (N = 20. Deep intraspecific divergences overlapping with among-species differences were detected in 48 species, often with samples from large geographic areas and several including multiple subspecies. This strong population genetic structure often coincided with breaks between different ecoregions or areas of endemism. CONCLUSIONS: The taxonomic uncertainty associated with the high incidence of non-monophyletic species and discovery of putative species obscures studies of historical patterns of species diversification in the Neotropical region. We showed that COI barcodes are a valuable tool to indicate which taxa would benefit from more extensive taxonomic revisions with multilocus approaches. Moreover, our results support hypotheses that the megadiversity of birds in the region is associated with multiple geographic processes starting well before the Quaternary and extending to more recent

  4. Nitrogen detected TROSY at high field yields high resolution and sensitivity for protein NMR

    International Nuclear Information System (INIS)

    Takeuchi, Koh; Arthanari, Haribabu; Shimada, Ichio; Wagner, Gerhard

    2015-01-01

    Detection of 15 N in multidimensional NMR experiments of proteins has sparsely been utilized because of the low gyromagnetic ratio (γ) of nitrogen and the presumed low sensitivity of such experiments. Here we show that selecting the TROSY components of proton-attached 15 N nuclei (TROSY 15 N H ) yields high quality spectra in high field magnets (>600 MHz) by taking advantage of the slow 15 N transverse relaxation and compensating for the inherently low 15 N sensitivity. The 15 N TROSY transverse relaxation rates increase modestly with molecular weight but the TROSY gain in peak heights depends strongly on the magnetic field strength. Theoretical simulations predict that the narrowest line width for the TROSY 15 N H component can be obtained at 900 MHz, but sensitivity reaches its maximum around 1.2 GHz. Based on these considerations, a 15 N-detected 2D 1 H– 15 N TROSY-HSQC ( 15 N-detected TROSY-HSQC) experiment was developed and high-quality 2D spectra were recorded at 800 MHz in 2 h for 1 mM maltose-binding protein at 278 K (τ c  ∼ 40 ns). Unlike for 1 H detected TROSY, deuteration is not mandatory to benefit 15 N detected TROSY due to reduced dipolar broadening, which facilitates studies of proteins that cannot be deuterated, especially in cases where production requires eukaryotic expression systems. The option of recording 15 N TROSY of proteins expressed in H 2 O media also alleviates the problem of incomplete amide proton back exchange, which often hampers the detection of amide groups in the core of large molecular weight proteins that are expressed in D 2 O culture media and cannot be refolded for amide back exchange. These results illustrate the potential of 15 N H -detected TROSY experiments as a means to exploit the high resolution offered by high field magnets near and above 1 GHz

  5. Nitrogen detected TROSY at high field yields high resolution and sensitivity for protein NMR

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Koh [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan); Arthanari, Haribabu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States); Shimada, Ichio, E-mail: shimada@iw-nmr.f.u-tokyo.ac.jp [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan); Wagner, Gerhard, E-mail: gerhard-wagner@hms.harvard.edu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States)

    2015-12-15

    Detection of {sup 15}N in multidimensional NMR experiments of proteins has sparsely been utilized because of the low gyromagnetic ratio (γ) of nitrogen and the presumed low sensitivity of such experiments. Here we show that selecting the TROSY components of proton-attached {sup 15}N nuclei (TROSY {sup 15}N{sub H}) yields high quality spectra in high field magnets (>600 MHz) by taking advantage of the slow {sup 15}N transverse relaxation and compensating for the inherently low {sup 15}N sensitivity. The {sup 15}N TROSY transverse relaxation rates increase modestly with molecular weight but the TROSY gain in peak heights depends strongly on the magnetic field strength. Theoretical simulations predict that the narrowest line width for the TROSY {sup 15}N{sub H} component can be obtained at 900 MHz, but sensitivity reaches its maximum around 1.2 GHz. Based on these considerations, a {sup 15}N-detected 2D {sup 1}H–{sup 15}N TROSY-HSQC ({sup 15}N-detected TROSY-HSQC) experiment was developed and high-quality 2D spectra were recorded at 800 MHz in 2 h for 1 mM maltose-binding protein at 278 K (τ{sub c} ∼ 40 ns). Unlike for {sup 1}H detected TROSY, deuteration is not mandatory to benefit {sup 15}N detected TROSY due to reduced dipolar broadening, which facilitates studies of proteins that cannot be deuterated, especially in cases where production requires eukaryotic expression systems. The option of recording {sup 15}N TROSY of proteins expressed in H{sub 2}O media also alleviates the problem of incomplete amide proton back exchange, which often hampers the detection of amide groups in the core of large molecular weight proteins that are expressed in D{sub 2}O culture media and cannot be refolded for amide back exchange. These results illustrate the potential of {sup 15}N{sub H}-detected TROSY experiments as a means to exploit the high resolution offered by high field magnets near and above 1 GHz.

  6. Acoustic detection of ultra-high energy cascades in ice

    Energy Technology Data Exchange (ETDEWEB)

    Boeser, S.

    2006-12-08

    Current underwater optical neutrino telescopes are designed to detect neutrinos from astrophysical sources with energies in the TeV range. Due to the low fluxes and small cross sections, no high energy neutrinos of extraterrestrial origin have been observed so far. Only the Cherenkov neutrino detectors on the km{sup 3} scale that are currently under construction will have the necessary volume to observe these rare interactions. For the guaranteed source of neutrinos from interactions of the ultra-high energy cosmic at EeV energies rays with the ambient cosmic microwave background, event rates of only one per year are expected in these experiments. To measure the flux and verify the predicted cross sections of these cosmogenic neutrinos, an observed volume of the order of 100 km{sup 3} will be necessary, that will not be feasible with existing detection techniques. Alternative methods are required to build a detector on these scales. One promising idea is to record the acoustic waves generated in hadronic or electromagnetic cascades following the neutrino interaction. The higher amplitudes of the sonic signal and the large expected absorption length of sound favour South Polar ice instead of sea water as a medium. The prerequisites for an estimate of the potential of such a detector are suitable acoustic sensors, a verification of the model of thermo-acoustic sound generation and a determination of the acoustic properties of the ice. In a theoretical derivation the mechanism of thermo-elastic excitation of acoustic waves was shown to be equivalent for isotropic solids and liquids. Following a detailed analysis of the existing knowledge a simulation study of a hybrid optical-radio-acoustic detector has been performed. Ultrasonic sensors dedicated to in-ice application were developed and have been used to record acoustic signals from intense proton and laser beams in water and ice. With the obtained experience, the hitherto largest array of acoustic sensors and

  7. Acoustic detection of ultra-high energy cascades in ice

    International Nuclear Information System (INIS)

    Boeser, S.

    2006-01-01

    Current underwater optical neutrino telescopes are designed to detect neutrinos from astrophysical sources with energies in the TeV range. Due to the low fluxes and small cross sections, no high energy neutrinos of extraterrestrial origin have been observed so far. Only the Cherenkov neutrino detectors on the km 3 scale that are currently under construction will have the necessary volume to observe these rare interactions. For the guaranteed source of neutrinos from interactions of the ultra-high energy cosmic at EeV energies rays with the ambient cosmic microwave background, event rates of only one per year are expected in these experiments. To measure the flux and verify the predicted cross sections of these cosmogenic neutrinos, an observed volume of the order of 100 km 3 will be necessary, that will not be feasible with existing detection techniques. Alternative methods are required to build a detector on these scales. One promising idea is to record the acoustic waves generated in hadronic or electromagnetic cascades following the neutrino interaction. The higher amplitudes of the sonic signal and the large expected absorption length of sound favour South Polar ice instead of sea water as a medium. The prerequisites for an estimate of the potential of such a detector are suitable acoustic sensors, a verification of the model of thermo-acoustic sound generation and a determination of the acoustic properties of the ice. In a theoretical derivation the mechanism of thermo-elastic excitation of acoustic waves was shown to be equivalent for isotropic solids and liquids. Following a detailed analysis of the existing knowledge a simulation study of a hybrid optical-radio-acoustic detector has been performed. Ultrasonic sensors dedicated to in-ice application were developed and have been used to record acoustic signals from intense proton and laser beams in water and ice. With the obtained experience, the hitherto largest array of acoustic sensors and transmitters was

  8. Detection of heavy metal ions in drinking water using a high-resolution differential surface plasmon resonance sensor.

    Science.gov (United States)

    Forzani, Erica S; Zhang, Haiqian; Chen, Wilfred; Tao, Nongjian

    2005-03-01

    We have built a high-resolution differential surface plasmon resonance (SPR) sensor for heavy metal ion detection. The sensor surface is divided into a reference and sensing areas, and the difference in the SPR angles from the two areas is detected with a quadrant cell photodetector as a differential signal. In the presence of metal ions, the differential signal changes due to specific binding of the metal ions onto the sensing area coated with properly selected peptides, which provides an accurate real-time measurement and quantification of the metal ions. Selective detection of Cu2+ and Ni2+ in the ppt-ppb range was achieved by coating the sensing surface with peptides NH2-Gly-Gly-His-COOH and NH2-(His)6-COOH. Cu2+ in drinking water was tested using this sensor.

  9. Hybrid quadrupole-orbitrap mass spectrometry analysis with accurate-mass database and parallel reaction monitoring for high-throughput screening and quantification of multi-xenobiotics in honey.

    Science.gov (United States)

    Li, Yi; Zhang, Jinzhen; Jin, Yue; Wang, Lin; Zhao, Wen; Zhang, Wenwen; Zhai, Lifei; Zhang, Yaping; Zhang, Yongxin; Zhou, Jinhui

    2016-01-15

    This study reports a rapid, automated screening and quantification method for the determination of multi-xenobiotic residues in honey using ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-Q-Orbitrap) with a user-built accurate-mass database plus parallel reaction monitoring (PRM). The database contains multi-xenobiotic information including formulas, adduct types, theoretical exact mass and retention time, characteristic fragment ions, ion ratios, and mass accuracies. A simple sample preparation method was developed to reduce xenobiotic loss in the honey samples. The screening method was validated based on retention time deviation, mass accuracy via full scan-data-dependent MS/MS (full scan-ddMS2), multi-isotope ratio, characteristic ion ratio, sensitivity, and positive/negative switching performance between the spiked sample and corresponding standard solution. The quantification method based on the PRM mode is a promising new quantitative tool which we validated in terms of selectivity, linearity, recovery (accuracy), repeatability (precision), decision limit (CCα), detection capability (CCβ), matrix effects, and carry-over. The optimized methods proposed in this study enable the automated screening and quantification of 157 compounds in less than 15 min in honey. The results of this study, as they represent a convenient protocol for large-scale screening and quantification, also provide a research approach for analysis of various contaminants in other matrices. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. High-throughput phenotyping to detect drought tolerance QTL in wild barley introgression lines

    KAUST Repository

    Honsdorf, Nora; March, Timothy John; Berger, Bettina; Tester, Mark A.; Pillen, Klaus

    2014-01-01

    and well watered treatments. High correlation (r = 0.98) between image based biomass estimates and actual biomass was demonstrated, and the suitability of the system to accurately and non-destructively estimate biomass was validated. Subsequently

  11. Colorimetric biomimetic sensor systems based on molecularly imprinted polymer membranes for highly-selective detection of phenol in environmental samples

    Directory of Open Access Journals (Sweden)

    Sergeyeva T. A.

    2014-05-01

    Full Text Available Aim. Development of an easy-to-use colorimetric sensor system for fast and accurate detection of phenol in envi- ronmental samples. Methods. Technique of molecular imprinting, method of in situ polymerization of molecularly imprinted polymer membranes. Results. The proposed sensor is based on free-standing molecularly imprinted polymer (MIP membranes, synthesized by in situ polymerization, and having in their structure artificial binding sites capable of selective phenol recognition. The quantitative detection of phenol, selectively adsorbed by the MIP membranes, is based on its reaction with 4-aminoantipyrine, which gives a pink-colored product. The intensity of staining of the MIP membrane is proportional to phenol concentration in the analyzed sample. Phenol can be detected within the range 50 nM–10 mM with limit of detection 50 nM, which corresponds to the concentrations that have to be detected in natural and waste waters in accordance with environmental protection standards. Stability of the MIP-membrane-based sensors was assessed during 12 months storage at room temperature. Conclusions. The sensor system provides highly-selective and sensitive detection of phenol in both mo- del and real (drinking, natural, and waste water samples. As compared to traditional methods of phenol detection, the proposed system is characterized by simplicity of operation and can be used in non-laboratory conditions.

  12. High-resolution focal plane array IR detection modules and digital signal processing technologies at AIM

    Science.gov (United States)

    Cabanski, Wolfgang A.; Breiter, Rainer; Koch, R.; Mauk, Karl-Heinz; Rode, Werner; Ziegler, Johann; Eberhardt, Kurt; Oelmaier, Reinhard; Schneider, Harald; Walther, Martin

    2000-07-01

    Full video format focal plane array (FPA) modules with up to 640 X 512 pixels have been developed for high resolution imaging applications in either mercury cadmium telluride (MCT) mid wave (MWIR) infrared (IR) or platinum silicide (PtSi) and quantum well infrared photodetector (QWIP) technology as low cost alternatives to MCT for high performance IR imaging in the MWIR or long wave spectral band (LWIR). For the QWIP's, a new photovoltaic technology was introduced for improved NETD performance and higher dynamic range. MCT units provide fast frame rates > 100 Hz together with state of the art thermal resolution NETD hardware platforms and software for image visualization and nonuniformity correction including scene based self learning algorithms had to be developed to accomplish for the high data rates of up to 18 M pixels/s with 14-bit deep data, allowing to take into account nonlinear effects to access the full NETD by accurate reduction of residual fixed pattern noise. The main features of these modules are summarized together with measured performance data for long range detection systems with moderately fast to slow F-numbers like F/2.0 - F/3.5. An outlook shows most recent activities at AIM, heading for multicolor and faster frame rate detector modules based on MCT devices.

  13. Accurate x-ray spectroscopy

    International Nuclear Information System (INIS)

    Deslattes, R.D.

    1987-01-01

    Heavy ion accelerators are the most flexible and readily accessible sources of highly charged ions. These having only one or two remaining electrons have spectra whose accurate measurement is of considerable theoretical significance. Certain features of ion production by accelerators tend to limit the accuracy which can be realized in measurement of these spectra. This report aims to provide background about spectroscopic limitations and discuss how accelerator operations may be selected to permit attaining intrinsically limited data

  14. Automated Solar Flare Detection and Feature Extraction in High-Resolution and Full-Disk Hα Images

    Science.gov (United States)

    Yang, Meng; Tian, Yu; Liu, Yangyi; Rao, Changhui

    2018-05-01

    In this article, an automated solar flare detection method applied to both full-disk and local high-resolution Hα images is proposed. An adaptive gray threshold and an area threshold are used to segment the flare region. Features of each detected flare event are extracted, e.g. the start, peak, and end time, the importance class, and the brightness class. Experimental results have verified that the proposed method can obtain more stable and accurate segmentation results than previous works on full-disk images from Big Bear Solar Observatory (BBSO) and Kanzelhöhe Observatory for Solar and Environmental Research (KSO), and satisfying segmentation results on high-resolution images from the Goode Solar Telescope (GST). Moreover, the extracted flare features correlate well with the data given by KSO. The method may be able to implement a more complicated statistical analysis of Hα solar flares.

  15. Accomplishments of the MUSICA project to provide accurate, long-term, global and high-resolution observations of tropospheric {H2O,δD} pairs - a review

    Science.gov (United States)

    Schneider, Matthias; Wiegele, Andreas; Barthlott, Sabine; González, Yenny; Christner, Emanuel; Dyroff, Christoph; García, Omaira E.; Hase, Frank; Blumenstock, Thomas; Sepúlveda, Eliezer; Mengistu Tsidu, Gizaw; Takele Kenea, Samuel; Rodríguez, Sergio; Andrey, Javier

    2016-07-01

    In the lower/middle troposphere, {H2O,δD} pairs are good proxies for moisture pathways; however, their observation, in particular when using remote sensing techniques, is challenging. The project MUSICA (MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water) addresses this challenge by integrating the remote sensing with in situ measurement techniques. The aim is to retrieve calibrated tropospheric {H2O,δD} pairs from the middle infrared spectra measured from ground by FTIR (Fourier transform infrared) spectrometers of the NDACC (Network for the Detection of Atmospheric Composition Change) and the thermal nadir spectra measured by IASI (Infrared Atmospheric Sounding Interferometer) aboard the MetOp satellites. In this paper, we present the final MUSICA products, and discuss the characteristics and potential of the NDACC/FTIR and MetOp/IASI {H2O,δD} data pairs. First, we briefly resume the particularities of an {H2O,δD} pair retrieval. Second, we show that the remote sensing data of the final product version are absolutely calibrated with respect to H2O and δD in situ profile references measured in the subtropics, between 0 and 7 km. Third, we reveal that the {H2O,δD} pair distributions obtained from the different remote sensors are consistent and allow distinct lower/middle tropospheric moisture pathways to be identified in agreement with multi-year in situ references. Fourth, we document the possibilities of the NDACC/FTIR instruments for climatological studies (due to long-term monitoring) and of the MetOp/IASI sensors for observing diurnal signals on a quasi-global scale and with high horizontal resolution. Fifth, we discuss the risk of misinterpreting {H2O,δD} pair distributions due to incomplete processing of the remote sensing products.

  16. High Magnetic Field in THz Plasma Wave Detection by High Electron Mobility Transistors

    Science.gov (United States)

    Sakowicz, M.; Łusakowski, J.; Karpierz, K.; Grynberg, M.; Valusis, G.

    The role of gated and ungated two dimensional (2D) electron plasma in THz detection by high electron mobility transistors (HEMTs) was investigated. THz response of GaAs/AlGaAs and GaN/AlGaN HEMTs was measured at 4.4K in quantizing magnetic fields with a simultaneous modulation of the gate voltage UGS. This allowed us to measure both the detection signal, S, and its derivative dS/dUGS. Shubnikov - de-Haas oscillations (SdHO) of both S and dS/dUGS were observed. A comparison of SdHO observed in detection and magnetoresistance measurements allows us to associate unambiguously SdHO in S and dS/dUGS with the ungated and gated parts of the transistor channel, respectively. This allows us to conclude that the entire channel takes part in the detection process. Additionally, in the case of GaAlAs/GaAs HEMTs, a structure related to the cyclotron resonance transition was observed.

  17. High Hydrogen Content Graphene Hydride Compounds & High Cross-Section Cladding Coatings for Fast Neutron Detection

    International Nuclear Information System (INIS)

    Chandrashekhar, MVS

    2017-01-01

    The objective is to develop and implement a superior low-cost, large area (potentially >32in), easily deployable, close proximity, harsh environment innovative neutron sensor needed for next generation fuel cycle monitoring. We will exploit recent breakthroughs at the PI's lab on the electrochemistry of epitaxial graphene (EG) formed on commercial SiC wafers, a transformative nanomaterial system with superior radiation detection and durability properties to develop a new paradigm in detection for fast neutrons, a by-product of fission reactors. There are currently few effective detection/monitoring schemes, especially solid-state ones at present. This is essential for monitoring and control of future fuel cycles to make them more efficient and reliable. By exploiting these novel materials, as well as innovative hybrid SiC/EG/Cladding device architectures conceived by the team, will develop low-cost, high performance solutions to fast-neutron detection. Finally, we will also explore 3-terminal device implementations for neutron detectors with built-in electronic gain to further shrink these devices and improve their sensitivity.

  18. Detection of argan oil adulteration with vegetable oils by high-performance liquid chromatography-evaporative light scattering detection.

    Science.gov (United States)

    Salghi, Rachid; Armbruster, Wolfgang; Schwack, Wolfgang

    2014-06-15

    Triacylglycerol profiles were selected as indicator of adulteration of argan oils to carry out a rapid screening of samples for the evaluation of authenticity. Triacylglycerols were separated by high-performance liquid chromatography-evaporative light scattering detection. Different peak area ratios were defined to sensitively detect adulteration of argan oil with vegetable oils such as sunflower, soy bean, and olive oil up to the level of 5%. Based on four reference argan oils, mean limits of detection and quantitation were calculated to approximately 0.4% and 1.3%, respectively. Additionally, 19 more argan oil reference samples were analysed by high-performance liquid chromatography-refractive index detection, resulting in highly comparative results. The overall strategy demonstrated a good applicability in practise, and hence a high potential to be transferred to routine laboratories. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Improved Diffuse Fluorescence Flow Cytometer Prototype for High Sensitivity Detection of Rare Circulating Cells In Vivo

    Science.gov (United States)

    Pestana, Noah Benjamin

    Accurate quantification of circulating cell populations is important in many areas of pre-clinical and clinical biomedical research, for example, in the study of cancer metastasis or the immune response following tissue and organ transplants. Normally this is done "ex-vivo" by drawing and purifying a small volume of blood and then analyzing it with flow cytometry, hemocytometry or microfludic devices, but the sensitivity of these techniques are poor and the process of handling samples has been shown to affect cell viability and behavior. More recently "in vivo flow cytometry" (IVFC) techniques have been developed where fluorescently-labeled cells flowing in a small blood vessel in the ear or retina are analyzed, but the sensitivity is generally poor due to the small sampling volume. To address this, our group recently developed a method known as "Diffuse Fluorescence Flow Cytometry" (DFFC) that allows detection and counting of rare circulating cells with diffuse photons, offering extremely high single cell counting sensitivity. In this thesis, an improved DFFC prototype was designed and validated. The chief improvements were three-fold, i) improved optical collection efficiency, ii) improved detection electronics, and iii) development of a method to mitigate motion artifacts during in vivo measurements. In combination, these improvements yielded an overall instrument detection sensitivity better than 1 cell/mL in vivo, which is the most sensitive IVFC system reported to date. Second, development and validation of a low-cost microfluidic device reader for analysis of ocular fluids is described. We demonstrate that this device has equivalent or better sensitivity and accuracy compared a fluorescence microscope, but at an order-of-magnitude reduced cost with simplified operation. Future improvements to both instruments are also discussed.

  20. Rapid detection of SMARCB1 sequence variation using high resolution melting

    Directory of Open Access Journals (Sweden)

    Ashley David M

    2009-12-01

    Full Text Available Abstract Background Rhabdoid tumors are rare cancers of early childhood arising in the kidney, central nervous system and other organs. The majority are caused by somatic inactivating mutations or deletions affecting the tumor suppressor locus SMARCB1 [OMIM 601607]. Germ-line SMARCB1 inactivation has been reported in association with rhabdoid tumor, epitheloid sarcoma and familial schwannomatosis, underscoring the importance of accurate mutation screening to ascertain recurrence and transmission risks. We describe a rapid and sensitive diagnostic screening method, using high resolution melting (HRM, for detecting sequence variations in SMARCB1. Methods Amplicons, encompassing the nine coding exons of SMARCB1, flanking splice site sequences and the 5' and 3' UTR, were screened by both HRM and direct DNA sequencing to establish the reliability of HRM as a primary mutation screening tool. Reaction conditions were optimized with commercially available HRM mixes. Results The false negative rate for detecting sequence variants by HRM in our sample series was zero. Nine amplicons out of a total of 140 (6.4% showed variant melt profiles that were subsequently shown to be false positive. Overall nine distinct pathogenic SMARCB1 mutations were identified in a total of 19 possible rhabdoid tumors. Two tumors had two distinct mutations and two harbored SMARCB1 deletion. Other mutations were nonsense or frame-shifts. The detection sensitivity of the HRM screening method was influenced by both sequence context and specific nucleotide change and varied from 1: 4 to 1:1000 (variant to wild-type DNA. A novel method involving digital HRM, followed by re-sequencing, was used to confirm mutations in tumor specimens containing associated normal tissue. Conclusions This is the first report describing SMARCB1 mutation screening using HRM. HRM is a rapid, sensitive and inexpensive screening technology that is likely to be widely adopted in diagnostic laboratories to

  1. Rapid detection of SMARCB1 sequence variation using high resolution melting

    International Nuclear Information System (INIS)

    Dagar, Vinod; Chow, Chung-Wo; Ashley, David M; Algar, Elizabeth M

    2009-01-01

    Rhabdoid tumors are rare cancers of early childhood arising in the kidney, central nervous system and other organs. The majority are caused by somatic inactivating mutations or deletions affecting the tumor suppressor locus SMARCB1 [OMIM 601607]. Germ-line SMARCB1 inactivation has been reported in association with rhabdoid tumor, epitheloid sarcoma and familial schwannomatosis, underscoring the importance of accurate mutation screening to ascertain recurrence and transmission risks. We describe a rapid and sensitive diagnostic screening method, using high resolution melting (HRM), for detecting sequence variations in SMARCB1. Amplicons, encompassing the nine coding exons of SMARCB1, flanking splice site sequences and the 5' and 3' UTR, were screened by both HRM and direct DNA sequencing to establish the reliability of HRM as a primary mutation screening tool. Reaction conditions were optimized with commercially available HRM mixes. The false negative rate for detecting sequence variants by HRM in our sample series was zero. Nine amplicons out of a total of 140 (6.4%) showed variant melt profiles that were subsequently shown to be false positive. Overall nine distinct pathogenic SMARCB1 mutations were identified in a total of 19 possible rhabdoid tumors. Two tumors had two distinct mutations and two harbored SMARCB1 deletion. Other mutations were nonsense or frame-shifts. The detection sensitivity of the HRM screening method was influenced by both sequence context and specific nucleotide change and varied from 1: 4 to 1:1000 (variant to wild-type DNA). A novel method involving digital HRM, followed by re-sequencing, was used to confirm mutations in tumor specimens containing associated normal tissue. This is the first report describing SMARCB1 mutation screening using HRM. HRM is a rapid, sensitive and inexpensive screening technology that is likely to be widely adopted in diagnostic laboratories to facilitate whole gene mutation screening

  2. Circumstances under which various approximate relativistic and nonrelativistic theories yield accurate Compton scattering doubly differential cross sections at high photon energy

    International Nuclear Information System (INIS)

    LaJohn, L A; Pratt, R H

    2009-01-01

    We discuss the increase in error with increasing nuclear charge Z in the use of the relativistic impulse approximation (RIA) for the calculation of Compton K-shell scattering doubly differential cross sections (DDCS). We also show that nonrelativistic (nr) expressions can be used to obtain accurate peak region DDCS at scattering angles less than about 35 0 even at incident photon energies ω i exceeding 1 MeV, if Z<30. This is possible because in the Compton peak region, as θ→0, a low momentum transfer limit is being approached.

  3. Detection of Doppler Microembolic Signals Using High Order Statistics

    Directory of Open Access Journals (Sweden)

    Maroun Geryes

    2016-01-01

    Full Text Available Robust detection of the smallest circulating cerebral microemboli is an efficient way of preventing strokes, which is second cause of mortality worldwide. Transcranial Doppler ultrasound is widely considered the most convenient system for the detection of microemboli. The most common standard detection is achieved through the Doppler energy signal and depends on an empirically set constant threshold. On the other hand, in the past few years, higher order statistics have been an extensive field of research as they represent descriptive statistics that can be used to detect signal outliers. In this study, we propose new types of microembolic detectors based on the windowed calculation of the third moment skewness and fourth moment kurtosis of the energy signal. During energy embolus-free periods the distribution of the energy is not altered and the skewness and kurtosis signals do not exhibit any peak values. In the presence of emboli, the energy distribution is distorted and the skewness and kurtosis signals exhibit peaks, corresponding to the latter emboli. Applied on real signals, the detection of microemboli through the skewness and kurtosis signals outperformed the detection through standard methods. The sensitivities and specificities reached 78% and 91% and 80% and 90% for the skewness and kurtosis detectors, respectively.

  4. Accuracy of High-Resolution Ultrasonography in the Detection of Extensor Tendon Lacerations.

    Science.gov (United States)

    Dezfuli, Bobby; Taljanovic, Mihra S; Melville, David M; Krupinski, Elizabeth A; Sheppard, Joseph E

    2016-02-01

    Lacerations to the extensor mechanism are usually diagnosed clinically. Ultrasound (US) has been a growing diagnostic tool for tendon injuries since the 1990s. To date, there has been no publication establishing the accuracy and reliability of US in the evaluation of extensor mechanism lacerations in the hand. The purpose of this study is to determine the accuracy of US to detect extensor tendon injuries in the hand. Sixteen fingers and 4 thumbs in 4 fresh-frozen and thawed cadaveric hands were used. Sixty-eight 0.5-cm transverse skin lacerations were created. Twenty-seven extensor tendons were sharply transected. The remaining skin lacerations were used as sham dissection controls. One US technologist and one fellowship-trained musculoskeletal radiologist performed real-time dynamic US studies in and out of water bath. A second fellowship trained musculoskeletal radiologist subsequently reviewed the static US images. Dynamic and static US interpretation accuracy was assessed using dissection as "truth." All 27 extensor tendon lacerations and controls were identified correctly with dynamic imaging as either injury models that had a transected extensor tendon or sham controls with intact extensor tendons (sensitivity = 100%, specificity = 100%, positive predictive value = 1.0; all significantly greater than chance). Static imaging had a sensitivity of 85%, specificity of 89%, and accuracy of 88% (all significantly greater than chance). The results of the dynamic real time versus static US imaging were clearly different but did not reach statistical significance. Diagnostic US is a very accurate noninvasive study that can identify extensor mechanism injuries. Clinically suspected cases of acute extensor tendon injury scanned by high-frequency US can aid and/or confirm the diagnosis, with dynamic imaging providing added value compared to static. Ultrasonography, to aid in the diagnosis of extensor mechanism lacerations, can be successfully used in a reliable and

  5. Rapid and high-throughput detection of highly pathogenic bacteria by Ibis PLEX-ID technology.

    Directory of Open Access Journals (Sweden)

    Daniela Jacob

    Full Text Available In this manuscript, we describe the identification of highly pathogenic bacteria using an assay coupling biothreat group-specific PCR with electrospray ionization mass spectrometry (PCR/ESI-MS run on an Ibis PLEX-ID high-throughput platform. The biothreat cluster assay identifies most of the potential bioterrorism-relevant microorganisms including Bacillus anthracis, Francisella tularensis, Yersinia pestis, Burkholderia mallei and pseudomallei, Brucella species, and Coxiella burnetii. DNA from 45 different reference materials with different formulations and different concentrations were chosen and sent to a service screening laboratory that uses the PCR/ESI-MS platform to provide a microbial identification service. The standard reference materials were produced out of a repository built up in the framework of the EU funded project "Establishment of Quality Assurances for Detection of Highly Pathogenic Bacteria of Potential Bioterrorism Risk" (EQADeBa. All samples were correctly identified at least to the genus level.

  6. Accurate antemortem diagnosis of equine protozoal myeloencephalitis (EPM) based on detecting intrathecal antibodies against Sarcocystis neurona using the SnSAG2 and SnSAG4/3 ELISAs.

    Science.gov (United States)

    Reed, S M; Howe, D K; Morrow, J K; Graves, A; Yeargan, M R; Johnson, A L; MacKay, R J; Furr, M; Saville, W J A; Williams, N M

    2013-01-01

    Recent work demonstrated the value of antigen-specific antibody indices (AI and C-value) to detect intrathecal antibody production against Sarcocystis neurona for antemortem diagnosis of equine protozoal myeloencephalitis (EPM). The study was conducted to assess whether the antigen-specific antibody indices can be reduced to a simple serum : cerebrospinal fluid (CSF) titer ratio to achieve accurate EPM diagnosis. Paired serum and CSF samples from 128 horses diagnosed by postmortem examination. The sample set included 44 EPM cases, 35 cervical-vertebral malformation (CVM) cases, 39 neurologic cases other than EPM or CVM, and 10 non-neurologic cases. Antibodies against S. neurona were measured in serum and CSF pairs using the SnSAG2 and SnSAG4/3 (SnSAG2, 4/3) ELISAs, and the ratio of each respective serum titer to CSF titer was determined. Likelihood ratios and diagnostic sensitivity and specificity were calculated based on serum titers, CSF titers, and serum : CSF titer ratios. Excellent diagnostic sensitivity and specificity was obtained from the SnSAG2, 4/3 serum : CSF titer ratio. Sensitivity and specificity of 93.2 and 81.1%, respectively, were achieved using a ratio cutoff of ≤100, whereas sensitivity and specificity were 86.4 and 95.9%, respectively, if a more rigorous cutoff of ≤50 was used. Antibody titers in CSF also provided good diagnostic accuracy. Serum antibody titers alone yielded much lower sensitivity and specificity. The study confirms the value of detecting intrathecal antibody production for antemortem diagnosis of EPM, and they further show that the antigen-specific antibody indices can be reduced in practice to a simple serum : CSF titer ratio. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  7. FPGA-based High-Performance Collision Detection: An Enabling Technique for Image-Guided Robotic Surgery

    Directory of Open Access Journals (Sweden)

    Zhaorui Zhang

    2016-08-01

    Full Text Available Collision detection, which refers to the computational problem of finding the relative placement or con-figuration of two or more objects, is an essential component of many applications in computer graphics and robotics. In image-guided robotic surgery, real-time collision detection is critical for preserving healthy anatomical structures during the surgical procedure. However, the computational complexity of the problem usually results in algorithms that operate at low speed. In this paper, we present a fast and accurate algorithm for collision detection between Oriented-Bounding-Boxes (OBBs that is suitable for real-time implementation. Our proposed Sweep and Prune algorithm can perform a preliminary filtering to reduce the number of objects that need to be tested by the classical Separating Axis Test algorithm, while the OBB pairs of interest are preserved. These OBB pairs are re-checked by the Separating Axis Test algorithm to obtain accurate overlapping status between them. To accelerate the execution, our Sweep and Prune algorithm is tailor-made for the proposed method. Meanwhile, a high performance scalable hardware architecture is proposed by analyzing the intrinsic parallelism of our algorithm, and is implemented on FPGA platform. Results show that our hardware design on the FPGA platform can achieve around 8X higher running speed than the software design on a CPU platform. As a result, the proposed algorithm can achieve a collision frame rate of 1 KHz, and fulfill the requirement for the medical surgery scenario of Robot Assisted Laparoscopy.

  8. Smart Sensor Based Obstacle Detection for High-Speed Unmanned Surface Vehicle

    DEFF Research Database (Denmark)

    Hermann, Dan; Galeazzi, Roberto; Andersen, Jens Christian

    2015-01-01

    This paper describes an obstacle detection system for a high-speed and agile unmanned surface vehicle (USV), running at speeds up to 30 m/s. The aim is a real-time and high performance obstacle detection system using both radar and vision technologies to detect obstacles within a range of 175 m. ...... performance using sensor fusion of radar and computer vision....

  9. Determination of accurate 1H positions of an alanine tripeptide with anti-parallel and parallel β-sheet structures by high resolution 1H solid state NMR and GIPAW chemical shift calculation.

    Science.gov (United States)

    Yazawa, Koji; Suzuki, Furitsu; Nishiyama, Yusuke; Ohata, Takuya; Aoki, Akihiro; Nishimura, Katsuyuki; Kaji, Hironori; Shimizu, Tadashi; Asakura, Tetsuo

    2012-11-25

    The accurate (1)H positions of alanine tripeptide, A(3), with anti-parallel and parallel β-sheet structures could be determined by highly resolved (1)H DQMAS solid-state NMR spectra and (1)H chemical shift calculation with gauge-including projector augmented wave calculations.

  10. High Density Nano-Electrode Array for Radiation Detection

    International Nuclear Information System (INIS)

    Misra, Mano

    2010-01-01

    Bulk single crystals of Cd 1-x Zn x Te (x=0.04 to x=0.2) compound semiconductor is used for room temperature radiation detection. The production of large volume of Cd 1-x Zn x Te with low defect density is expensive. As a result there is a growing research interest in the production of nanostructured compound semiconductors such as Cd 1-x Zn x Te in an electrochemical route. In this investigation, Cd 1-x Zn x Te ternary compound semiconductor, referred as CZT, was electrodeposited in the form of nanowires onto a TiO 2 nanotubular template from propylene carbonate as the non-aqueous electrolyte, using a pulse-reverse electrodeposition process at 130 C. The template acted as a support in growing ordered nanowire of CZT which acts as a one dimensional conductor. Cyclic Voltammogram (CV) studies were conducted in determining the potentials for the growth of nanowires of uniform stoichiometry. The morphologies and composition of CZT were characterized by using SEM, TEM and XRD. The STEM mapping carried out on the nanowires showed the uniform distribution of Cd, Zn and Te elements. TEM image showed that the nanowires were polycrystalline in nature. The Mott-Schottky analysis carried on the nanowires showed that the nanowires were a p-type semiconductor. The carrier density, band gap and resistivity of the Cd 0.9 Zn 0.1 Te nanowires were 4.29 x 10 13 cm -3 , 1.56 eV and 2.76 x 10 11 (Omega)-cm respectively. The high resistivity was attributed to the presence of deep defect states such as cadmium vacancies or Te antisites which were created by the anodic cycle of the pulse-reverse electrodeposition process. Stacks of series connected CZT nanowire arrays were tested with different bias potentials. The background current was in the order of tens of picoamperes. When exposed to radiation source Amerecium-241 (60 KeV, 4 (micro)Ci), the stacked CZT nanowires arrays showed sensing behavior. The sensitivity of the nanowire arrays increased as the number of stacks increased. The

  11. High Density Nano-Electrode Array for Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Mano Misra

    2010-05-07

    Bulk single crystals of Cd1-xZnxTe (x=0.04 to x=0.2) compound semiconductor is used for room temperature radiation detection. The production of large volume of Cd1-xZnxTe with low defect density is expensive. As a result there is a growing research interest in the production of nanostructured compound semiconductors such as Cd1-xZnxTe in an electrochemical route. In this investigation, Cd1-xZnxTe ternary compound semiconductor, referred as CZT, was electrodeposited in the form of nanowires onto a TiO2 nanotubular template from propylene carbonate as the non-aqueous electrolyte, using a pulse-reverse electrodeposition process at 130 ºC. The template acted as a support in growing ordered nanowire of CZT which acts as a one dimensional conductor. Cyclic Voltammogram (CV) studies were conducted in determining the potentials for the growth of nanowires of uniform stoichiometry. The morphologies and composition of CZT were characterized by using SEM, TEM and XRD. The STEM mapping carried out on the nanowires showed the uniform distribution of Cd, Zn and Te elements. TEM image showed that the nanowires were polycrystalline in nature. The Mott-Schottky analysis carried on the nanowires showed that the nanowires were a p-type semiconductor. The carrier density, band gap and resistivity of the Cd0.9Zn0.1Te nanowires were 4.29x1013 cm-3, 1.56 eV and 2.76x1011Ω-cm respectively. The high resistivity was attributed to the presence of deep defect states such as cadmium vacancies or Te antisites which were created by the anodic cycle of the pulse-reverse electrodeposition process. Stacks of series connected CZT nanowire arrays were tested with different bias potentials. The background current was in the order of tens of picoamperes. When exposed to radiation source Amerecium-241 (60 KeV, 4 μCi), the stacked CZT nanowires arrays showed sensing behavior. The sensitivity of the nanowire arrays increased as the number of stacks increased. The preliminary results indicate that the

  12. Accurate Quantitation of Water-amide Proton Exchange Rates Using the Phase-Modulated CLEAN Chemical EXchange (CLEANEX-PM) Approach with a Fast-HSQC (FHSQC) Detection Scheme

    International Nuclear Information System (INIS)

    Hwang, Tsang-Lin; Zijl, Peter C.M. van; Mori, Susumu

    1998-01-01

    Measurement of exchange rates between water and NH protons by magnetization transfer methods is often complicated by artifacts, such as intramolecular NOEs, and/or TOCSY transfer from Cα protons coincident with the water frequency, or exchange-relayed NOEs from fast exchanging hydroxyl or amine protons. By applying the Phase-Modulated CLEAN chemical EXchange (CLEANEX-PM) spin-locking sequence, 135 o (x) 120 o (-x) 110 o (x) 110 o (-x) 120 o (x) 135 o (-x) during the mixing period, these artifacts can be eliminated, revealing an unambiguous water-NH exchange spectrum. In this paper, the CLEANEX-PM mixing scheme is combined with Fast-HSQC (FHSQC) detection and used to obtain accurate chemical exchange rates from the initial slope analysis for a sample of 15N labeled staphylococcal nuclease. The results are compared to rates obtained using Water EXchange filter (WEX) II-FHSQC, and spin-echo-filtered WEX II-FHSQC measurements, and clearly identify the spurious NOE contributions in the exchange system

  13. Remotely detected high-field MRI of porous samples

    Science.gov (United States)

    Seeley, Juliette A.; Han, Song-I.; Pines, Alexander

    2004-04-01

    Remote detection of NMR is a novel technique in which an NMR-active sensor surveys an environment of interest and retains memory of that environment to be recovered at a later time in a different location. The NMR or MRI information about the sensor nucleus is encoded and stored as spin polarization at the first location and subsequently moved to a different physical location for optimized detection. A dedicated probe incorporating two separate radio frequency (RF)—circuits was built for this purpose. The encoding solenoid coil was large enough to fit around the bulky sample matrix, while the smaller detection solenoid coil had not only a higher quality factor, but also an enhanced filling factor since the coil volume comprised purely the sensor nuclei. We obtained two-dimensional (2D) void space images of two model porous samples with resolution less than 1.4 mm 2. The remotely reconstructed images demonstrate the ability to determine fine structure with image quality superior to their directly detected counterparts and show the great potential of NMR remote detection for imaging applications that suffer from low sensitivity due to low concentrations and filling factor.

  14. Accurate quantum chemical calculations

    Science.gov (United States)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1989-01-01

    An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.

  15. Highly sensitive BTX detection using surface functionalized QCM sensor

    Energy Technology Data Exchange (ETDEWEB)

    Bozkurt, Asuman Aşıkoğlu; Özdemir, Okan; Altındal, Ahmet, E-mail: altindal@yildiz.edu.tr [Department of Physics, Yildiz Technical University, Davutpasa, 34210 Istanbul (Turkey)

    2016-03-25

    A novel organic compound was designed and successfully synthesized for the fabrication of QCM based sensors to detect the low concentrations of BTX gases in indoor air. The effect of the long-range electron orbital delocalization on the BTX vapour sensing properties of azo-bridged Pcs based chemiresistor-type sensors have also been investigated in this work. The sensing behaviour of the film for the online detection of volatile organic solvent vapors was investigated by utilizing an AT-cut quartz crystal resonator. It was observed that the adsorption of the target molecules on the coating surface cause a reversible negative frequency shift of the resonator. Thus, a variety of solvent vapors can be detected by using the phthalocyanine film as sensitive coating, with sensitivity in the ppm range and response times in the order of several seconds depending on the molecular structure of the organic solvent.

  16. Detecting high-frequency gravitational waves with optically levitated sensors.

    Science.gov (United States)

    Arvanitaki, Asimina; Geraci, Andrew A

    2013-02-15

    We propose a tunable resonant sensor to detect gravitational waves in the frequency range of 50-300 kHz using optically trapped and cooled dielectric microspheres or microdisks. The technique we describe can exceed the sensitivity of laser-based gravitational wave observatories in this frequency range, using an instrument of only a few percent of their size. Such a device extends the search volume for gravitational wave sources above 100 kHz by 1 to 3 orders of magnitude, and could detect monochromatic gravitational radiation from the annihilation of QCD axions in the cloud they form around stellar mass black holes within our galaxy due to the superradiance effect.

  17. Rapid, highly sensitive and highly specific gene detection by combining enzymatic amplification and DNA chip detection simultaneously

    Directory of Open Access Journals (Sweden)

    Koji Hashimoto

    2016-05-01

    Full Text Available We have developed a novel gene detection method based on the loop-mediated isothermal amplification (LAMP reaction and the DNA dissociation reaction on the same DNA chip surface to achieve a lower detection limit, broader dynamic range and faster detection time than are attainable with a conventional DNA chip. Both FAM- and thiol-labeled DNA probe bound to the complementary sequence accompanying Dabcyl was immobilized on the gold surface via Au/thiol bond. The LAMP reaction was carried out on the DNA probe fixed gold surface. At first, Dabcyl molecules quenched the FAM fluorescence. According to the LAMP reaction, the complementary sequence with Dabcyl was competitively reacted with the amplified targeted sequence. As a result, the FAM fluorescence increased owing to dissociation of the complementary sequence from the DNA probe. The simultaneous reaction of LAMP and DNA chip detection was achieved, and 103 copies of the targeted gene were detected within an hour by measuring fluorescence intensity of the DNA probe. Keywords: Biosensor, DNA chip, Loop-mediated isothermal amplification (LAMP, Fluorescence detection, Gold substrate, Au/thiol bond

  18. Leak detection system for a high temperature fluid pipe

    International Nuclear Information System (INIS)

    Puyal, C.; Meuwisse, C.

    1989-01-01

    The leak detection system is made by a cable with at least two isolated electrical conductors, close to the wall of the pipe. The material of the cable is chosen so as to change its electrical characteristics if a leak causes heating of the cable. A detector at one end of the cable can measure the modifications of the electrical characteristics [fr

  19. Real time avalanche detection for high risk areas.

    Science.gov (United States)

    2014-12-01

    Avalanches routinely occur on State Highway 21 (SH21) between Lowman and Stanley, Idaho each winter. The avalanches pose : a threat to the safety of maintenance workers and the traveling public. A real-time avalanche detection system will allow the :...

  20. Food safety evaluation: Detection and confirmation of chloramphenicol in milk by high performance liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    Nicolich, Rebecca S.; Werneck-Barroso, Eduardo; Marques, Marlice A. Sipoli

    2006-01-01

    A simple and rapid procedure for extraction of chloramphenicol (CAP) in milk and analysis by high-performance liquid chromatography coupled with quadrupole mass spectrometry in tandem was developed. The method consisted of one step of liquid-liquid extraction using ethyl acetate and acidified water (10 mmol L -1 formic acid) and HPLC-MS/MS detection. CAP-D5 was used as internal standard. The method was validated according to Commission Decision 2002/657/EC. The calibration curves were linear, with typical r 2 values higher than 0.98. Absolute recovery of CAP from milk proved to be more than 95%, however CAP-D5 absolute recovery was 75%. The method was accurate and reproducible, being successfully applied to the monitoring of CAP in milk samples obtained from the Brazilian market. Decision limit (CCα) was 0.05 ng mL -1 and detection capability (CCβ) was 0.09 ng mL -1

  1. A New Method Based on Two-Stage Detection Mechanism for Detecting Ships in High-Resolution SAR Images

    Directory of Open Access Journals (Sweden)

    Xu Yongli

    2017-01-01

    Full Text Available Ship detection in synthetic aperture radar (SAR remote sensing images, being a fundamental but challenging problem in the field of satellite image analysis, plays an important role for a wide range of applications and is receiving significant attention in recent years. Aiming at the requirements of ship detection in high-resolution SAR images, the accuracy, the intelligent level, a better real-time operation and processing efficiency, The characteristics of ocean background and ship target in high-resolution SAR images were analyzed, we put forward a ship detection algorithm in high-resolution SAR images. The algorithm consists of two detection stages: The first step designs a pre-training classifier based on improved spectral residual visual model to obtain the visual salient regions containing ship targets quickly, then achieve the purpose of probably detection of ships. In the second stage, considering the Bayesian theory of binary hypothesis detection, a local maximum posterior probability (MAP classifier is designed for the classification of pixels. After the parameter estimation and judgment criterion, the classification of pixels are carried out in the target areas to achieve the classification of two types of pixels in the salient regions. In the paper, several types of satellite image data, such as TerraSAR-X (TS-X, Radarsat-2, are used to evaluate the performance of detection methods. Comparing with classical CFAR detection algorithms, experimental results show that the algorithm can achieve a better effect of suppressing false alarms, which caused by the speckle noise and ocean clutter background inhomogeneity. At the same time, the detection speed is increased by 25% to 45%.

  2. A Comparative Study of Data Mining Algorithms for High Detection Rate in Intrusion Detection System

    Directory of Open Access Journals (Sweden)

    Nabeela Ashraf

    2018-01-01

    Full Text Available Due to the fast growth and tradition of the internet over the last decades, the network security problems are increasing vigorously. Humans can not handle the speed of processes and the huge amount of data required to handle network anomalies. Therefore, it needs substantial automation in both speed and accuracy. Intrusion Detection System is one of the approaches to recognize illegal access and rare attacks to secure networks. In this proposed paper, Naive Bayes, J48 and Random Forest classifiers are compared to compute the detection rate and accuracy of IDS. For experiments, the KDD_NSL dataset is used.

  3. Detection of genomic variation by selection of a 9 mb DNA region and high throughput sequencing.

    Directory of Open Access Journals (Sweden)

    Sergey I Nikolaev

    Full Text Available Detection of the rare polymorphisms and causative mutations of genetic diseases in a targeted genomic area has become a major goal in order to understand genomic and phenotypic variability. We have interrogated repeat-masked regions of 8.9 Mb on human chromosomes 21 (7.8 Mb and 7 (1.1 Mb from an individual from the International HapMap Project (NA12872. We have optimized a method of genomic selection for high throughput sequencing. Microarray-based selection and sequencing resulted in 260-fold enrichment, with 41% of reads mapping to the target region. 83% of SNPs in the targeted region had at least 4-fold sequence coverage and 54% at least 15-fold. When assaying HapMap SNPs in NA12872, our sequence genotypes are 91.3% concordant in regions with coverage > or = 4-fold, and 97.9% concordant in regions with coverage > or = 15-fold. About 81% of the SNPs recovered with both thresholds are listed in dbSNP. We observed that regions with low sequence coverage occur in close proximity to low-complexity DNA. Validation experiments using Sanger sequencing were performed for 46 SNPs with 15-20 fold coverage, with a confirmation rate of 96%, suggesting that DNA selection provides an accurate and cost-effective method for identifying rare genomic variants.

  4. High-sensitivity detection of cardiac troponin I with UV LED excitation for use in point-of-care immunoassay.

    Science.gov (United States)

    Rodenko, Olga; Eriksson, Susann; Tidemand-Lichtenberg, Peter; Troldborg, Carl Peder; Fodgaard, Henrik; van Os, Sylvana; Pedersen, Christian

    2017-08-01

    High-sensitivity cardiac troponin assay development enables determination of biological variation in healthy populations, more accurate interpretation of clinical results and points towards earlier diagnosis and rule-out of acute myocardial infarction. In this paper, we report on preliminary tests of an immunoassay analyzer employing an optimized LED excitation to measure on a standard troponin I and a novel research high-sensitivity troponin I assay. The limit of detection is improved by factor of 5 for standard troponin I and by factor of 3 for a research high-sensitivity troponin I assay, compared to the flash lamp excitation. The obtained limit of detection was 0.22 ng/L measured on plasma with the research high-sensitivity troponin I assay and 1.9 ng/L measured on tris-saline-azide buffer containing bovine serum albumin with the standard troponin I assay. We discuss the optimization of time-resolved detection of lanthanide fluorescence based on the time constants of the system and analyze the background and noise sources in a heterogeneous fluoroimmunoassay. We determine the limiting factors and their impact on the measurement performance. The suggested model can be generally applied to fluoroimmunoassays employing the dry-cup concept.

  5. Rapid Detection and Identification of Human Hookworm Infections through High Resolution Melting (HRM) Analysis

    Science.gov (United States)

    Ngui, Romano; Lim, Yvonne A. L.; Chua, Kek Heng

    2012-01-01

    Background Hookworm infections are still endemic in low and middle income tropical countries with greater impact on the socioeconomic and public health of the bottom billion of the world's poorest people. In this study, a real-time polymerase chain reaction (PCR) coupled with high resolution melting-curve (HRM) analysis was evaluated for an accurate, rapid and sensitive tool for species identification focusing on the five human hookworm species. Methods Real-time PCR coupled with HRM analysis targeting the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA as the genetic marker was used to identify and distinguish hookworm species in human samples. Unique and distinct characteristics of HRM patterns were produced for each of the five hookworm species. The melting curves were characterized by peaks of 79.24±0.05°C and 83.00±0.04°C for Necator americanus, 79.12±0.10°C for Ancylostoma duodenale, 79.40±0.10°C for Ancylostoma ceylanicum, 79.63±0.05°C for Ancylostoma caninum and 79.70±0.14°C for Ancylostoma braziliense. An evaluation of the method's sensitivity and specificity revealed that this assay was able to detect as low as 0.01 ng/µl hookworm DNA and amplification was only recorded for hookworm positive samples. Conclusion The HRM assay developed in this study is a rapid and straightforward method for the diagnosis, identification and discrimination of five human hookworms. This assay is simple compared to other probe-based genotyping methods as it does not require multiplexing, DNA sequencing or post-PCR processing. Therefore, this method offers a new alternative for rapid detection of human hookworm species. PMID:22844538

  6. High-accuracy detection of early Parkinson's Disease using multiple characteristics of finger movement while typing.

    Directory of Open Access Journals (Sweden)

    Warwick R Adams

    Full Text Available Parkinson's Disease (PD is a progressive neurodegenerative movement disease affecting over 6 million people worldwide. Loss of dopamine-producing neurons results in a range of both motor and non-motor symptoms, however there is currently no definitive test for PD by non-specialist clinicians, especially in the early disease stages where the symptoms may be subtle and poorly characterised. This results in a high misdiagnosis rate (up to 25% by non-specialists and people can have the disease for many years before diagnosis. There is a need for a more accurate, objective means of early detection, ideally one which can be used by individuals in their home setting. In this investigation, keystroke timing information from 103 subjects (comprising 32 with mild PD severity and the remainder non-PD controls was captured as they typed on a computer keyboard over an extended period and showed that PD affects various characteristics of hand and finger movement and that these can be detected. A novel methodology was used to classify the subjects' disease status, by utilising a combination of many keystroke features which were analysed by an ensemble of machine learning classification models. When applied to two separate participant groups, this approach was able to successfully discriminate between early-PD subjects and controls with 96% sensitivity, 97% specificity and an AUC of 0.98. The technique does not require any specialised equipment or medical supervision, and does not rely on the experience and skill of the practitioner. Regarding more general application, it currently does not incorporate a second cardinal disease symptom, so may not differentiate PD from similar movement-related disorders.

  7. Rapid detection and identification of human hookworm infections through high resolution melting (HRM analysis.

    Directory of Open Access Journals (Sweden)

    Romano Ngui

    Full Text Available BACKGROUND: Hookworm infections are still endemic in low and middle income tropical countries with greater impact on the socioeconomic and public health of the bottom billion of the world's poorest people. In this study, a real-time polymerase chain reaction (PCR coupled with high resolution melting-curve (HRM analysis was evaluated for an accurate, rapid and sensitive tool for species identification focusing on the five human hookworm species. METHODS: Real-time PCR coupled with HRM analysis targeting the second internal transcribed spacer (ITS-2 of nuclear ribosomal DNA as the genetic marker was used to identify and distinguish hookworm species in human samples. Unique and distinct characteristics of HRM patterns were produced for each of the five hookworm species. The melting curves were characterized by peaks of 79.24±0.05°C and 83.00±0.04°C for Necator americanus, 79.12±0.10°C for Ancylostoma duodenale, 79.40±0.10°C for Ancylostoma ceylanicum, 79.63±0.05°C for Ancylostoma caninum and 79.70±0.14°C for Ancylostoma braziliense. An evaluation of the method's sensitivity and specificity revealed that this assay was able to detect as low as 0.01 ng/µl hookworm DNA and amplification was only recorded for hookworm positive samples. CONCLUSION: The HRM assay developed in this study is a rapid and straightforward method for the diagnosis, identification and discrimination of five human hookworms. This assay is simple compared to other probe-based genotyping methods as it does not require multiplexing, DNA sequencing or post-PCR processing. Therefore, this method offers a new alternative for rapid detection of human hookworm species.

  8. Optical detection of random features for high security applications

    Science.gov (United States)

    Haist, T.; Tiziani, H. J.

    1998-02-01

    Optical detection of random features in combination with digital signatures based on public key codes in order to recognize counterfeit objects will be discussed. Without applying expensive production techniques objects are protected against counterfeiting. Verification is done off-line by optical means without a central authority. The method is applied for protecting banknotes. Experimental results for this application are presented. The method is also applicable for identity verification of a credit- or chip-card holder.

  9. Towards autonomous radio detection of ultra high energy cosmic rays

    International Nuclear Information System (INIS)

    Garcon, Th.

    2010-01-01

    The radio-detection of extensive air showers, investigated for the first time in the 1960's, obtained promising results but plagued by the technical limitations. At that time, H.R. Allan summed up the state of the art in an extensive review article whose conclusions and predictions are still used today. Set up in 2001 at the Nancay Observatory, the CODALEMA experiment was built first as a demonstrator and successfully showed the feasibility of the radio-detection of extensive air showers. Radically modified in 2005, it allowed to obtain a clear energy correlation, and put in evidence an unambiguous signature of the geomagnetic origin of the electric field emission process associated to the air shower. The switch towards large areas is the next step of the technique's development. Therefore, the autonomy of the detectors becomes essential. After test prototypes installed in 2006 at the Pierre Auger Observatory, a generation of new autonomous detectors was developed. Their first results will be presented. This work is also dedicated to the issues related to the radio-detection technique: the antenna response, the sensitivity, the surrounding effects, the monitoring of a big array. The determination of the shower characteristics independently of other detectors such as the lateral distribution, the energy correlation and the frequency spectrum of the radio transient will be discussed. (author)

  10. Countercurrent chromatography separation of saponins by skeleton type from Ampelozizyphus amazonicus for off-line ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry analysis and characterisation.

    Science.gov (United States)

    de Souza Figueiredo, Fabiana; Celano, Rita; de Sousa Silva, Danila; das Neves Costa, Fernanda; Hewitson, Peter; Ignatova, Svetlana; Piccinelli, Anna Lisa; Rastrelli, Luca; Guimarães Leitão, Suzana; Guimarães Leitão, Gilda

    2017-01-20

    Ampelozizyphus amazonicus Ducke (Rhamnaceae), a medicinal plant used to prevent malaria, is a climbing shrub, native to the Amazonian region, with jujubogenin glycoside saponins as main compounds. The crude extract of this plant is too complex for any kind of structural identification, and HPLC separation was not sufficient to resolve this issue. Therefore, the aim of this work was to obtain saponin enriched fractions from the bark ethanol extract by countercurrent chromatography (CCC) for further isolation and identification/characterisation of the major saponins by HPLC and MS. The butanol extract was fractionated by CCC with hexane - ethyl acetate - butanol - ethanol - water (1:6:1:1:6; v/v) solvent system yielding 4 group fractions. The collected fractions were analysed by UHPLC-HRMS (ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry) and MS n . Group 1 presented mainly oleane type saponins, and group 3 showed mainly jujubogenin glycosides, keto-dammarane type triterpene saponins and saponins with C 31 skeleton. Thus, CCC separated saponins from the butanol-rich extract by skeleton type. A further purification of group 3 by CCC (ethyl acetate - ethanol - water (1:0.2:1; v/v)) and HPLC-RI was performed in order to obtain these unusual aglycones in pure form. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras

    Science.gov (United States)

    2017-10-01

    ARL-TR-8185 ● OCT 2017 US Army Research Laboratory Field Test Data for Detecting Vibrations of a Building Using High-Speed Video...Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras by Caitlin P Conn and Geoffrey H Goldman Sensors and...June 2016 – October 2017 4. TITLE AND SUBTITLE Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras 5a. CONTRACT

  12. The Centers for Disease Control and Prevention definition of mucosal barrier injury-associated bloodstream infection improves accurate detection of preventable bacteremia rates at a pediatric cancer center in a low- to middle-income country.

    Science.gov (United States)

    Torres, Dara; González, Miriam L; Loera, Adriana; Aguilera, Marco; Relyea, George; Aristizabal, Paula; Caniza, Miguela A

    2016-04-01

    The US National Healthcare Safety Network has provided a definition of mucosal barrier injury-associated, laboratory-confirmed bloodstream infection (MBI-LCBI) to improve infection surveillance. To date there is little information about its influence in pediatric oncology centers in low- to middle-income countries. To determine the influence of the definition on the rate of central line-associated bloodstream infection (CLABSI) and compare the clinical characteristics of MBI versus non-MBI LCBI cases. We retrospectively applied the National Healthcare Safety Network definition to all CLABSIs recorded at a pediatric oncology center in Tijuana, Mexico, from January 2011 through December 2014. CLABSI events were reclassified according to the MBI-LCBI definition. Clinical characteristics and outcomes of MBI and non-MBI CLABSIs were compared. Of 55 CLABSI events, 44% (24 out of 55) qualified as MBI-LCBIs; all were MBI-LCBI subcategory 1 (intestinal flora pathogens). After the number of MBI-LCBI cases was removed from the numerator, the CLABSI rate during the study period decreased from 5.72-3.22 infections per 1,000 central line days. Patients with MBI-LCBI were significantly younger than non-MBI-LCBI patients (P = .029) and had a significantly greater frequency of neutropenia (100% vs 39%; P = .001) and chemotherapy exposure (87% vs 58%; P = .020) and significantly longer median hospitalization (34 vs 23 days; P = .008). A substantial proportion of CLABSI events at our pediatric cancer center met the MBI-LCBI criteria. Our results support separate monitoring and reporting of MBI and non-MBI-LCBIs in low- to middle-income countries to allow accurate detection and tracking of preventable (non-MBI) bloodstream infections. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  13. High-resolution MRI in detecting subareolar breast abscess.

    Science.gov (United States)

    Fu, Peifen; Kurihara, Yasuyuki; Kanemaki, Yoshihide; Okamoto, Kyoko; Nakajima, Yasuo; Fukuda, Mamoru; Maeda, Ichiro

    2007-06-01

    Because subareolar breast abscess has a high recurrence rate, a more effective imaging technique is needed to comprehensively visualize the lesions and guide surgery. We performed a high-resolution MRI technique using a microscopy coil to reveal the characteristics and extent of subareolar breast abscess. High-resolution MRI has potential diagnostic value in subareolar breast abscess. This technique can be used to guide surgery with the aim of reducing the recurrence rate.

  14. NEW ACCURATE MEASUREMENT OF {sup 36}ArH{sup +} AND {sup 38}ArH{sup +} RO-VIBRATIONAL TRANSITIONS BY HIGH RESOLUTION IR ABSORPTION SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Cueto, M.; Herrero, V. J.; Tanarro, I.; Doménech, J. L. [Molecular Physics Department, Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, E-28006 Madrid (Spain); Cernicharo, J. [Department of Astrophysics, CAB. INTA-CSIC. Crta Torrejón-Ajalvir Km 4, E-28850 Torrejón de Ardoz, Madrid (Spain); Barlow, M. J.; Swinyard, B. M., E-mail: jl.domenech@csic.es [Department of Physics and Astronomy, University College London. Gower Street, London WC1E 6BT (United Kingdom)

    2014-03-01

    The protonated argon ion, {sup 36}ArH{sup +}, was recently identified in the Crab Nebula from Herschel spectra. Given the atmospheric opacity at the frequency of its J = 1-0 and J = 2-1 rotational transitions (617.5 and 1234.6 GHz, respectively), and the current lack of appropriate space observatories after the recent end of the Herschel mission, future studies on this molecule will rely on mid-infrared observations. We report on accurate wavenumber measurements of {sup 36}ArH{sup +} and {sup 38}ArH{sup +} rotation-vibration transitions in the v = 1-0 band in the range 4.1-3.7 μm (2450-2715 cm{sup –1}). The wavenumbers of the R(0) transitions of the v = 1-0 band are 2612.50135 ± 0.00033 and 2610.70177 ± 0.00042 cm{sup –1} (±3σ) for {sup 36}ArH{sup +} and {sup 38}ArH{sup +}, respectively. The calculated opacity for a gas thermalized at a temperature of 100 K and with a linewidth of 1 km s{sup –1} of the R(0) line is 1.6 × 10{sup –15} × N({sup 36}ArH{sup +}). For column densities of {sup 36}ArH{sup +} larger than 1 × 10{sup 13} cm{sup –2}, significant absorption by the R(0) line can be expected against bright mid-IR sources.

  15. Development of accurate dimethyl sulphide primary standard gas mixtures at low nanomole per mole levels in high-pressure aluminium cylinders for ambient measurements

    Science.gov (United States)

    Eon Kim, Mi; Kang, Ji Hwan; Doo Kim, Yong; Lee, Dong Soo; Lee, Sangil

    2018-04-01

    Dimethyl sulphide (DMS) plays an important role in atmospheric chemistry and climate change. Ambient DMS is monitored in a global network and reported at sub-nanomole per mole (nmol/mol) levels. Developing traceable, accurate DMS standards at ambient levels is essential for tracking the long-term trends and understanding the role of DMS in the atmosphere. Gravimetrically prepared gas standards in cylinders are widely used for calibrating instruments. Therefore, a stable primary standard gas mixture (PSM) is required for traceable ambient DMS measurement at remote sites. In this study, to evaluate adsorption loss on the internal surface of the gas cylinder, 6 nmol mol-1 DMS gas mixtures were prepared in three types of aluminium cylinders: a cylinder without a special coating on its internal surface (AL), an Aculife IV  +  III-treated cylinder (AC), and an Experis-treated cylinder (EX). There was little adsorption loss on the EX cylinder, whereas there was substantial adsorption loss on the other two cylinders. The EX cylinder was used to prepare 0.5, 2, 5, and 7 nmol mol-1 DMS PSMs with relative expanded uncertainties of less than 0.4%. The DMS PSMs were analytically verified and consistent within a relative expanded uncertainty of less than 1.2%. The long-term stability of the 7 nmol mol-1 DMS PSM was assessed by tracking the ratio of the DMS to the internal standard, benzene. The results showed that the DMS was stable for about seven months and it was projected to be stable for more than 60 months within a relative expanded uncertainty of 3%.

  16. The Use of Highly Sensitive Detection Methods for Eradication of Plasmodium

    DEFF Research Database (Denmark)

    Hede, Marianne Smedegaard; Knudsen, Birgitta R.

    2017-01-01

    The key to a successful malaria eradication program is highly efficient detection of Plasmodium infected people followed by appropriate treatment to avoid spreading of the parasite. We will discuss some of the demands that such a detection method needs to fulfill and review some of the advantages...... and disadvantages of currently available detection methods...

  17. High-speed asynchronous optical sampling for high-sensitivity detection of coherent phonons

    International Nuclear Information System (INIS)

    Dekorsy, T; Taubert, R; Hudert, F; Schrenk, G; Bartels, A; Cerna, R; Kotaidis, V; Plech, A; Koehler, K; Schmitz, J; Wagner, J

    2007-01-01

    A new optical pump-probe technique is implemented for the investigation of coherent acoustic phonon dynamics in the GHz to THz frequency range which is based on two asynchronously linked femtosecond lasers. Asynchronous optical sampling (ASOPS) provides the performance of on all-optical oscilloscope and allows us to record optically induced lattice dynamics over nanosecond times with femtosecond resolution at scan rates of 10 kHz without any moving part in the set-up. Within 1 minute of data acquisition time signal-to-noise ratios better than 10 7 are achieved. We present examples of the high-sensitivity detection of coherent phonons in superlattices and of the coherent acoustic vibration of metallic nanoparticles

  18. Combining the Pixel-based and Object-based Methods for Building Change Detection Using High-resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    ZHANG Zhiqiang

    2018-01-01

    Full Text Available Timely and accurate change detection of buildings provides important information for urban planning and management.Accompanying with the rapid development of satellite remote sensing technology,detecting building changes from high-resolution remote sensing images have received wide attention.Given that pixel-based methods of change detection often lead to low accuracy while object-based methods are complicated for uses,this research proposes a method that combines pixel-based and object-based methods for detecting building changes from high-resolution remote sensing images.First,based on the multiple features extracted from the high-resolution images,a random forest classifier is applied to detect changed building at the pixel level.Then,a segmentation method is applied to segement the post-phase remote sensing image and to get post-phase image objects.Finally,both changed building at the pixel level and post-phase image objects are fused to recognize the changed building objects.Multi-temporal QuickBird images are used as experiment data for building change detection with high-resolution remote sensing images,the results indicate that the proposed method could reduce the influence of environmental difference,such as light intensity and view angle,on building change detection,and effectively improve the accuracies of building change detection.

  19. A Highly Sensitive Porous Silicon (P-Si)-Based Human Kallikrein 2 (hK2) Immunoassay Platform toward Accurate Diagnosis of Prostate Cancer.

    Science.gov (United States)

    Lee, Sang Wook; Hosokawa, Kazuo; Kim, Soyoun; Jeong, Ok Chan; Lilja, Hans; Laurell, Thomas; Maeda, Mizuo