Science.gov

Sample records for adult detection efficiency

  1. Efficient human face detection in infancy.

    PubMed

    Jakobsen, Krisztina V; Umstead, Lindsey; Simpson, Elizabeth A

    2016-01-01

    Adults detect conspecific faces more efficiently than heterospecific faces; however, the development of this own-species bias (OSB) remains unexplored. We tested whether 6- and 11-month-olds exhibit OSB in their attention to human and animal faces in complex visual displays with high perceptual load (25 images competing for attention). Infants (n = 48) and adults (n = 43) passively viewed arrays containing a face among 24 non-face distractors while we measured their gaze with remote eye tracking. While OSB is typically not observed until about 9 months, we found that, already by 6 months, human faces were more likely to be detected, were detected more quickly (attention capture), and received longer looks (attention holding) than animal faces. These data suggest that 6-month-olds already exhibit OSB in face detection efficiency, consistent with perceptual attunement. This specialization may reflect the biological importance of detecting conspecific faces, a foundational ability for early social interactions.

  2. Efficient human face detection in infancy.

    PubMed

    Jakobsen, Krisztina V; Umstead, Lindsey; Simpson, Elizabeth A

    2016-01-01

    Adults detect conspecific faces more efficiently than heterospecific faces; however, the development of this own-species bias (OSB) remains unexplored. We tested whether 6- and 11-month-olds exhibit OSB in their attention to human and animal faces in complex visual displays with high perceptual load (25 images competing for attention). Infants (n = 48) and adults (n = 43) passively viewed arrays containing a face among 24 non-face distractors while we measured their gaze with remote eye tracking. While OSB is typically not observed until about 9 months, we found that, already by 6 months, human faces were more likely to be detected, were detected more quickly (attention capture), and received longer looks (attention holding) than animal faces. These data suggest that 6-month-olds already exhibit OSB in face detection efficiency, consistent with perceptual attunement. This specialization may reflect the biological importance of detecting conspecific faces, a foundational ability for early social interactions. PMID:26248583

  3. Energy Efficiency Adult Tracking Report - Final

    SciTech Connect

    Gibson-Grant, Amy

    2014-09-30

    Postwave tracking study for the Energy Efficiency Adult Campaign This study serves as measure of key metrics among the campaign’s target audience, homeowners age 25+. Key measures include: Awareness of messages relating to the broad issue; Recognition of the PSAs; Relevant attitudes, including interest, ease of taking energy efficient steps, and likelihood to act; Relevant knowledge, including knowledge of light bulb alternatives and energy efficient options; and Relevant behaviors, including specific energy-saving behaviors mentioned within the PSAs. Wave 1: May 27 – June 7, 2011 Wave 2: May 29 – June 8, 2012 Wave 3: May 29 – June 19, 2014 General market sample of adults 25+ who own their homes W1 sample: n = 704; W2: n=701; W3: n=806 Online Survey Panel Methodology Study was fielded by Lightspeed Research among their survey panel. Sample is US Census representative of US homeowners by race/ethnicity, income, age, region, and family status. At least 30% of respondents were required to have not updated major appliances in their home in the past 5 years (dishwasher, stove, refrigerator, washer, or dryer).

  4. Efficient detection in hyperspectral imagery.

    PubMed

    Schweizer, S M; Moura, J F

    2001-01-01

    Hyperspectral sensors collect hundreds of narrow and contiguously spaced spectral bands of data. Such sensors provide fully registered high resolution spatial and spectral images that are invaluable in discriminating between man-made objects and natural clutter backgrounds. The price paid for this high resolution data is extremely large data sets, several hundred of Mbytes for a single scene, that make storage and transmission difficult, thus requiring fast onboard processing techniques to reduce the data being transmitted. Attempts to apply traditional maximum likelihood detection techniques for in-flight processing of these massive amounts of hyperspectral data suffer from two limitations: first, they neglect the spatial correlation of the clutter by treating it as spatially white noise; second, their computational cost renders them prohibitive without significant data reduction like by grouping the spectral bands into clusters, with a consequent loss of spectral resolution. This paper presents a maximum likelihood detector that successfully confronts both problems: rather than ignoring the spatial and spectral correlations, our detector exploits them to its advantage; and it is computationally expedient, its complexity increasing only linearly with the number of spectral bands available. Our approach is based on a Gauss-Markov random field (GMRF) modeling of the clutter, which has the advantage of providing a direct parameterization of the inverse of the clutter covariance, the quantity of interest in the test statistic. We discuss in detail two alternative GMRF detectors: one based on a binary hypothesis approach, and the other on a "single" hypothesis formulation. We analyze extensively with real hyperspectral imagery data (HYDICE and SEBASS) the performance of the detectors, comparing them to a benchmark detector, the RX-algorithm. Our results show that the GMRF "single" hypothesis detector outperforms significantly in computational cost the RX

  5. Detection and Phenotypic Characterization of Adult Neurogenesis.

    PubMed

    Kuhn, H Georg; Eisch, Amelia J; Spalding, Kirsty; Peterson, Daniel A

    2016-03-01

    Studies of adult neurogenesis have greatly expanded in the last decade, largely as a result of improved tools for detecting and quantifying neurogenesis. In this review, we summarize and critically evaluate detection methods for neurogenesis in mammalian and human brain tissue. Besides thymidine analog labeling, cell-cycle markers are discussed, as well as cell stage and lineage commitment markers. Use of these histological tools is critically evaluated in terms of their strengths and limitations, as well as possible artifacts. Finally, we discuss the method of radiocarbon dating for determining cell and tissue turnover in humans.

  6. Violation of local realism versus detection efficiency

    SciTech Connect

    Massar, Serge; Pironio, Stefano

    2003-12-01

    We put bounds on the minimum detection efficiency necessary to violate local realism in Bell experiments. These bounds depend on simple parameters like the number of measurement settings or the dimensionality of the entangled quantum state. We derive them by constructing explicit local hidden variable models which reproduce the quantum correlations for sufficiently small detectors efficiency.

  7. Comodulation detection differences in children and adults

    PubMed Central

    Hall, Joseph W.; Buss, Emily; Grose, John H.

    2008-01-01

    This study investigated comodulation detection differences (CDD) in children (ages 4.8–10.1 years) and adults. The signal was 30-Hz wide band of noise centered on 2 kHz, and the masker consisted of six 30-Hz wide bands of noise spanning center frequencies from 870 to 4160 Hz. The envelopes of the masking bands were always comodulated, and the envelope of the signal was either comodulated or random with respect to the masker. In some conditions, the maskers were gated on prior to the signal in order to minimize effects related to perceptual fusion of the signal and masker. CDD was computed as the difference between signal detection thresholds in conditions where all bands were comodulated and conditions where the envelope of the signal was random with respect to the envelopes of the maskers. Values of CDD were generally small in children compared to adults. In contrast, masking release related to masker∕signal onset asynchrony was comparable across age groups. The small CDDs in children are discussed in terms of sensitivity to comodulation as a perceptual fusion cue and informational masking associated with the detection of a signal in a complex background, an effect that is ameliorated by asynchronous onset. PMID:18397027

  8. Aiming for Efficiency by Detecting Structural Similarity

    NASA Astrophysics Data System (ADS)

    Winter, Judith; Jeliazkov, Nikolay; Kühne, Gerold

    When applying XML-Retrieval in a distributed setting, efficiency issues have to be considered, e.g. reducing the network traffic involved in an swering a given query. The new Efficiency Track of INEX gave us the opportu nity to explore the possibility of improving both effectiveness and efficiency by exploiting structural similarity. We ran some of the track’s highly structured queries on our top-k search engine to analyze the impact of various structural similarity functions. We applied those functions first to the ranking and based on that to the query routing process. Our results indicate that detection of structural similarity can be used in order to re duce the amount of messages sent between distributed nodes and thus lead to more efficiency of the search.

  9. Efficient Computer Network Anomaly Detection by Changepoint Detection Methods

    NASA Astrophysics Data System (ADS)

    Tartakovsky, Alexander G.; Polunchenko, Aleksey S.; Sokolov, Grigory

    2013-02-01

    We consider the problem of efficient on-line anomaly detection in computer network traffic. The problem is approached statistically, as that of sequential (quickest) changepoint detection. A multi-cyclic setting of quickest change detection is a natural fit for this problem. We propose a novel score-based multi-cyclic detection algorithm. The algorithm is based on the so-called Shiryaev-Roberts procedure. This procedure is as easy to employ in practice and as computationally inexpensive as the popular Cumulative Sum chart and the Exponentially Weighted Moving Average scheme. The likelihood ratio based Shiryaev-Roberts procedure has appealing optimality properties, particularly it is exactly optimal in a multi-cyclic setting geared to detect a change occurring at a far time horizon. It is therefore expected that an intrusion detection algorithm based on the Shiryaev-Roberts procedure will perform better than other detection schemes. This is confirmed experimentally for real traces. We also discuss the possibility of complementing our anomaly detection algorithm with a spectral-signature intrusion detection system with false alarm filtering and true attack confirmation capability, so as to obtain a synergistic system.

  10. An efficient parallel termination detection algorithm

    SciTech Connect

    Baker, A. H.; Crivelli, S.; Jessup, E. R.

    2004-05-27

    Information local to any one processor is insufficient to monitor the overall progress of most distributed computations. Typically, a second distributed computation for detecting termination of the main computation is necessary. In order to be a useful computational tool, the termination detection routine must operate concurrently with the main computation, adding minimal overhead, and it must promptly and correctly detect termination when it occurs. In this paper, we present a new algorithm for detecting the termination of a parallel computation on distributed-memory MIMD computers that satisfies all of those criteria. A variety of termination detection algorithms have been devised. Of these, the algorithm presented by Sinha, Kale, and Ramkumar (henceforth, the SKR algorithm) is unique in its ability to adapt to the load conditions of the system on which it runs, thereby minimizing the impact of termination detection on performance. Because their algorithm also detects termination quickly, we consider it to be the most efficient practical algorithm presently available. The termination detection algorithm presented here was developed for use in the PMESC programming library for distributed-memory MIMD computers. Like the SKR algorithm, our algorithm adapts to system loads and imposes little overhead. Also like the SKR algorithm, ours is tree-based, and it does not depend on any assumptions about the physical interconnection topology of the processors or the specifics of the distributed computation. In addition, our algorithm is easier to implement and requires only half as many tree traverses as does the SKR algorithm. This paper is organized as follows. In section 2, we define our computational model. In section 3, we review the SKR algorithm. We introduce our new algorithm in section 4, and prove its correctness in section 5. We discuss its efficiency and present experimental results in section 6.

  11. Earthquake detection through computationally efficient similarity search.

    PubMed

    Yoon, Clara E; O'Reilly, Ossian; Bergen, Karianne J; Beroza, Gregory C

    2015-12-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection-identification of seismic events in continuous data-is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact "fingerprints" of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

  12. Earthquake detection through computationally efficient similarity search.

    PubMed

    Yoon, Clara E; O'Reilly, Ossian; Bergen, Karianne J; Beroza, Gregory C

    2015-12-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection-identification of seismic events in continuous data-is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact "fingerprints" of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes.

  13. Earthquake detection through computationally efficient similarity search

    PubMed Central

    Yoon, Clara E.; O’Reilly, Ossian; Bergen, Karianne J.; Beroza, Gregory C.

    2015-01-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection—identification of seismic events in continuous data—is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact “fingerprints” of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

  14. Waveform Fingerprinting for Efficient Seismic Signal Detection

    NASA Astrophysics Data System (ADS)

    Yoon, C. E.; OReilly, O. J.; Beroza, G. C.

    2013-12-01

    Cross-correlating an earthquake waveform template with continuous waveform data has proven a powerful approach for detecting events missing from earthquake catalogs. If templates do not exist, it is possible to divide the waveform data into short overlapping time windows, then identify window pairs with similar waveforms. Applying these approaches to earthquake monitoring in seismic networks has tremendous potential to improve the completeness of earthquake catalogs, but because effort scales quadratically with time, it rapidly becomes computationally infeasible. We develop a fingerprinting technique to identify similar waveforms, using only a few compact features of the original data. The concept is similar to human fingerprints, which utilize key diagnostic features to identify people uniquely. Analogous audio-fingerprinting approaches have accurately and efficiently found similar audio clips within large databases; example applications include identifying songs and finding copyrighted content within YouTube videos. In order to fingerprint waveforms, we compute a spectrogram of the time series, and segment it into multiple overlapping windows (spectral images). For each spectral image, we apply a wavelet transform, and retain only the sign of the maximum magnitude wavelet coefficients. This procedure retains just the large-scale structure of the data, providing both robustness to noise and significant dimensionality reduction. Each fingerprint is a high-dimensional, sparse, binary data object that can be stored in a database without significant storage costs. Similar fingerprints within the database are efficiently searched using locality-sensitive hashing. We test this technique on waveform data from the Northern California Seismic Network that contains events not detected in the catalog. We show that this algorithm successfully identifies similar waveforms and detects uncataloged low magnitude events in addition to cataloged events, while running to completion

  15. Effects of the detection efficiency on multiplicity distributions

    NASA Astrophysics Data System (ADS)

    Tang, A. H.; Wang, G.

    2013-08-01

    In this paper we investigate how a finite detection efficiency affects three popular multiplicity distributions, namely, the Poisson, the binomial, and the negative binomial distributions. We found that a multiplicity-independent detection efficiency does not change the characteristic of a distribution, while a multiplicity-dependent detection efficiency does. We layout a procedure to study the deviation of moments and their derivative quantities from the baseline distribution due to a multiplicity-dependent detection efficiency.

  16. Detection of Adult Green Sturgeon Using Environmental DNA Analysis

    PubMed Central

    Bergman, Paul S.; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California’s Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods. PMID:27096433

  17. Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

    PubMed

    Bergman, Paul S; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods. PMID:27096433

  18. Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

    PubMed

    Bergman, Paul S; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods.

  19. Carbon dioxide detection in adult Odonata.

    PubMed

    Piersanti, Silvana; Frati, Francesca; Rebora, Manuela; Salerno, Gianandrea

    2016-04-01

    The present paper shows, by means of single-cell recordings, responses of antennal sensory neurons of the damselfly Ischnura elegans when stimulated by air streams at different CO2 concentrations. Unlike most insects, but similarly to termites, centipedes and ticks, Odonata possess sensory neurons strongly inhibited by CO2, with the magnitude of the off-response depending upon the CO2 concentration. The Odonata antennal sensory neurons responding to CO2 are also sensitive to airborne odors; in particular, the impulse frequency is increased by isoamylamine and decreased by heptanoic and pentanoic acid. Further behavioral investigations are necessary to assign a biological role to carbon dioxide detection in Odonata. PMID:26831359

  20. Improving the efficiency of obstacle detection

    NASA Astrophysics Data System (ADS)

    Palchikov, V. P.; Budai, B. T.

    2016-09-01

    Obstacles should be timely detected in order to ensure safe driving of vehicles. It is shown that for this purpose a locator operating within the near IR-region must be used. A high-performance locator has been developed which provides high-precision measurement of distance to obstacles even in difficult observation conditions.

  1. Efficient target detection in cluttered FLIR imagery

    NASA Astrophysics Data System (ADS)

    Khan, Jesmin F.; Alam, Mohammad S.

    2005-03-01

    In this paper, we investigated automatic target detection and classification of low and high contrast targets present in unknown forward looking infrared (FLIR) image sequence. The detection algorithm, based on morphology based preprocessing, acts as a prescreener that selects possible candidate target regions, comprising both true targets and false alarms and places expected target-sized marker to those preselected regions. The application of simple non-linear grayscale operations in the proposed detection algorithm leads to real-time implementations. By considering the known target and background specific attributes, extracted from the training samples, the clutter rejection module discriminates between true target and false alarms previously identified by the detection algorithm. Two approaches are employed for object classification where one uses local features of the image and the other uses template matching technique such as image correlation. For the first approach, to extract features, we employed two methods - nonlinear filtering for texture energy measurement and wavelet decomposition by expending Daubechies high and low pass filter coefficients. Then for classification, a neural network based classifier is used. In the second approach minimax distance transform correlation filter (MDTCF) is applied that minimizes the average squared distance from the filtered true-class training images to a filtered reference image while maximizing the mean squared distance (MSD) of the filtered false-class training images to this filtered reference image. Then classification is performed using the squared distance of a filtered test image to the chosen filtered reference image. The performance of the proposed technique is analyzed for i) neural network with nonlinear texture filtering, ii) neural network with wavelet decomposition and iii) correlation filtering. Preliminary results indicate that the proposed detection algorithms can locate both hot and cold targets

  2. High-Collection-Efficiency Fluorescence Detection Cell

    NASA Technical Reports Server (NTRS)

    Hanisco, Thomas; Cazorla, Maria; Swanson, Andrew

    2013-01-01

    A new fluorescence cell has been developed for the laser induced fluorescence (LIF) detection of formaldehyde. The cell is used to sample a flow of air that contains trace concentrations of formaldehyde. The cell provides a hermetically sealed volume in which a flow of air containing formaldehyde can be illuminated by a laser. The cell includes the optics for transmitting the laser beam that is used to excite the formaldehyde and for collecting the resulting fluorescence. The novelty of the cell is its small size and simple design that provides a more robust and cheaper alternative to the state of the art. Despite its simplicity, the cell provides the same sensitivity to detection as larger, more complicated cells.

  3. Efficient detection of polyps in CT colonography

    NASA Astrophysics Data System (ADS)

    Wolf, Matthias; Cathier, Pascal; Lakare, Sarang; Dundar, Murat; Bogoni, Luca

    2007-03-01

    Colon cancer is a widespread disease and, according to the American Cancer Society, it is estimated that in 2006 more than 55,000 people will die of colon cancer in the US. However, early detection of colorectal polyps helps to drastically reduces mortality. Computer-Aided Detection (CAD) of colorectal polyps is a tool that could help physicians finding such lesions in CT scans of the colon. In this paper, we present the first phase, candidate generation (CG), of our technique for the detection of colonic polyp candidate locations in CT colonoscopy. Since polyps typically appear as protrusions on the surface of the colon, our cutting-plane algorithm identifies all those areas that can be "cut-off" using a plane. The key observation is that for any protruding lesion there is at least one plane that cuts a fragment off. Furthermore, the intersection between the plane and the polyp will typically be small and circular. On the other hand, a plane cannot cut a small circular cross-section from a wall or a fold, due to their concave or elongated paraboloid morphology, because these structures yield cross-sections that are much larger or non-circular. The algorithm has been incorporated as part of a prototype CAD system. An analysis on a test set of more than 400 patients yielded a high per-patient sensitivity of 95% and 90% in clean and tagged preparation respectively for polyps ranging from 6mm to 20mm in size.

  4. Efficiency of flight interception traps for adult Colorado potato beetles (Coleoptera: Chrysomelidae).

    PubMed

    Boiteau, G

    2000-06-01

    Interception traps have been used to monitor and sample Colorado potato beetle, Leptinotarsa decemlineata (Say), populations in flight, but the efficiency of these traps was unknown. The efficiency of interception window traps is limited because flying adults avoid the traps and may bounce off the trap without being collected. All trap types tested were avoided in flight chamber tests, including those constructed of transparent Plexiglas or yellow wood boards. A larger screen trap and a harp trap designed to reduce detection were also avoided by the beetles in flight. None of the traps provide a direct estimate of the number of adults randomly flying in the trap area. The highest level of efficiency for window traps was obtained with the yellow trap, which caught 16% of the expected flying population. Harp and screen traps without frames intercepted 60-62% of the expected flying population. The presence of a frame did not increase significantly the avoidance of the screen and harp traps by beetles in flight. Recommendations are made to maintain or increase the efficiency of some traps.

  5. Auditory Processing Efficiency and Temporal Resolution in Children and Adults.

    ERIC Educational Resources Information Center

    Hill, Penelope R.; Hartley, Douglas E.H.; Glasberg, Brian R.; Moore, Brian C.J.; Moore, David R.

    2004-01-01

    Children have higher auditory backward masking (BM) thresholds than adults. One explanation for this is poor temporal resolution, resulting in difficulty separating brief or rapidly presented sounds. This implies that the auditory temporal window is broader in children than in adults. Alternatively, elevated BM thresholds in children may indicate…

  6. Aerosol detection efficiency in inductively coupled plasma mass spectrometry

    DOE PAGES

    Hubbard, Joshua A.; Zigmond, Joseph A.

    2016-03-02

    We used an electrostatic size classification technique to segregate particles of known composition prior to being injected into an inductively coupled plasma mass spectrometer (ICP-MS). Moreover, we counted size-segregated particles with a condensation nuclei counter as well as sampled with an ICP-MS. By injecting particles of known size, composition, and aerosol concentration into the ICP-MS, efficiencies of the order of magnitude aerosol detection were calculated, and the particle size dependencies for volatile and refractory species were quantified. Similar to laser ablation ICP-MS, aerosol detection efficiency was defined as the rate at which atoms were detected in the ICP-MS normalized bymore » the rate at which atoms were injected in the form of particles. This method adds valuable insight into the development of technologies like laser ablation ICP-MS where aerosol particles (of relatively unknown size and gas concentration) are generated during ablation and then transported into the plasma of an ICP-MS. In this study, we characterized aerosol detection efficiencies of volatile species gold and silver along with refractory species aluminum oxide, cerium oxide, and yttrium oxide. Aerosols were generated with electrical mobility diameters ranging from 100 to 1000 nm. In general, it was observed that refractory species had lower aerosol detection efficiencies than volatile species, and there were strong dependencies on particle size and plasma torch residence time. Volatile species showed a distinct transition point at which aerosol detection efficiency began decreasing with increasing particle size. This critical diameter indicated the largest particle size for which complete particle detection should be expected and agreed with theories published in other works. Aerosol detection efficiencies also displayed power law dependencies on particle size. Aerosol detection efficiencies ranged from 10-5 to 10-11. Free molecular heat and mass transfer theory was

  7. Aerosol detection efficiency in inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hubbard, Joshua A.; Zigmond, Joseph A.

    2016-05-01

    An electrostatic size classification technique was used to segregate particles of known composition prior to being injected into an inductively coupled plasma mass spectrometer (ICP-MS). Size-segregated particles were counted with a condensation nuclei counter as well as sampled with an ICP-MS. By injecting particles of known size, composition, and aerosol concentration into the ICP-MS, efficiencies of the order of magnitude aerosol detection were calculated, and the particle size dependencies for volatile and refractory species were quantified. Similar to laser ablation ICP-MS, aerosol detection efficiency was defined as the rate at which atoms were detected in the ICP-MS normalized by the rate at which atoms were injected in the form of particles. This method adds valuable insight into the development of technologies like laser ablation ICP-MS where aerosol particles (of relatively unknown size and gas concentration) are generated during ablation and then transported into the plasma of an ICP-MS. In this study, we characterized aerosol detection efficiencies of volatile species gold and silver along with refractory species aluminum oxide, cerium oxide, and yttrium oxide. Aerosols were generated with electrical mobility diameters ranging from 100 to 1000 nm. In general, it was observed that refractory species had lower aerosol detection efficiencies than volatile species, and there were strong dependencies on particle size and plasma torch residence time. Volatile species showed a distinct transition point at which aerosol detection efficiency began decreasing with increasing particle size. This critical diameter indicated the largest particle size for which complete particle detection should be expected and agreed with theories published in other works. Aerosol detection efficiencies also displayed power law dependencies on particle size. Aerosol detection efficiencies ranged from 10- 5 to 10- 11. Free molecular heat and mass transfer theory was applied, but

  8. An efficient circle detector not relying on edge detection

    NASA Astrophysics Data System (ADS)

    Cai, Jia; Huang, Panfeng; Chen, Lu; Zhang, Bin

    2016-06-01

    Accurate and efficient detection of circular modules fixed on non-cooperative target is a key technology for Tethered Space Robot. This paper presents an efficient circle detector based on region-growing of gradient and histogram distribution of Euclidean distance. Region-growing of gradient is applied to generate arc support regions from single point. And the corresponding square fitting areas are defined to accelerate the detection and decrease storage. A histogram is then used to count frequency of the distances that participates in the accumulator and the parameters of each circle are acquired. Finally, a verification strategy of circular integrity is designed to test the detection results. We have tested our algorithm on 35 images dealing with kinds of circles and ellipses. Experimental results demonstrate that our method is able to detect circular objects under occlusion, image noises and moderate shape deformations with a good precision.

  9. Multichannel SNSPD system with high detection efficiency at telecommunication wavelength.

    PubMed

    Miki, Shigehito; Yamashita, Taro; Fujiwara, Mikio; Sasaki, Masahide; Wang, Zhen

    2010-07-01

    We developed a four-channel superconducting nanowire single-photon detector system based on a Gifford-McMahon cryocooler. All channels showed a system detection efficiency (DE) (at a 100 Hz dark-count rate) higher than 16% at 1550 nm wavelength, and the best channel showed a system DE of 21% and 30% at 1550 and 1310 nm wavelength, respectively.

  10. Efficient method for events detection in phonocardiographic signals

    NASA Astrophysics Data System (ADS)

    Martinez-Alajarin, Juan; Ruiz-Merino, Ramon

    2005-06-01

    The auscultation of the heart is still the first basic analysis tool used to evaluate the functional state of the heart, as well as the first indicator used to submit the patient to a cardiologist. In order to improve the diagnosis capabilities of auscultation, signal processing algorithms are currently being developed to assist the physician at primary care centers for adult and pediatric population. A basic task for the diagnosis from the phonocardiogram is to detect the events (main and additional sounds, murmurs and clicks) present in the cardiac cycle. This is usually made by applying a threshold and detecting the events that are bigger than the threshold. However, this method usually does not allow the detection of the main sounds when additional sounds and murmurs exist, or it may join several events into a unique one. In this paper we present a reliable method to detect the events present in the phonocardiogram, even in the presence of heart murmurs or additional sounds. The method detects relative maxima peaks in the amplitude envelope of the phonocardiogram, and computes a set of parameters associated with each event. Finally, a set of characteristics is extracted from each event to aid in the identification of the events. Besides, the morphology of the murmurs is also detected, which aids in the differentiation of different diseases that can occur in the same temporal localization. The algorithms have been applied to real normal heart sounds and murmurs, achieving satisfactory results.

  11. Efficient Spectral Endmember Detection Onboard the EO-1 Spacecraft

    NASA Technical Reports Server (NTRS)

    Bornstein, Ben; Thompson, David R.; Tran, Daniel; Bue, Brian; Chien, Steve; Castano, Rebecca

    2011-01-01

    Spaceflight and planetary exploration place severe constraints on the available bandwidth for downlinking large hyperspectral images. In addition, communications with spacecraft often occur intermittently, so mission-relevant hyperspectral data must wait for analysis on the ground before it can inform spacecraft activity planning. Onboard endmember detection can help alleviate these problems. It enables novelty detection and target identification for scheduling follow-up activities such as additional observation by narrow field of view instruments. Additionally, endmember analysis can facilitate data summary for downlink. This work describes a planned experiment of selective downlink by the EO-1 autonomous spacecraft. Here an efficient superpixel endmember detection algorithm keeps to the limited computational constraints of the flight processor. Tests suggest the procedure could enable significant improvements in downlink efficiency.

  12. Electrophysiological correlates of the efficient detection of emotional facial expressions.

    PubMed

    Sawada, Reiko; Sato, Wataru; Uono, Shota; Kochiyama, Takanori; Toichi, Motomi

    2014-04-29

    Behavioral studies have shown that emotional facial expressions are detected more rapidly and accurately than are neutral expressions. However, the neural mechanism underlying this efficient detection has remained unclear. To investigate this mechanism, we measured event-related potentials (ERPs) during a visual search task in which participants detected the normal emotional facial expressions of anger and happiness or their control stimuli, termed "anti-expressions," within crowds of neutral expressions. The anti-expressions, which were created using a morphing technique that produced changes equivalent to those in the normal emotional facial expressions compared with the neutral facial expressions, were most frequently recognized as emotionally neutral. Behaviorally, normal expressions were detected faster and more accurately and were rated as more emotionally arousing than were the anti-expressions. Regarding ERPs, the normal expressions elicited larger early posterior negativity (EPN) at 200-400ms compared with anti-expressions. Furthermore, larger EPN was related to faster and more accurate detection and higher emotional arousal. These data suggest that the efficient detection of emotional facial expressions is implemented via enhanced activation of the posterior visual cortices at 200-400ms based on their emotional significance. PMID:24594020

  13. Efficient method of image edge detection based on FSVM

    NASA Astrophysics Data System (ADS)

    Cai, Aiping; Xiong, Xiaomei

    2013-07-01

    For efficient object cover edge detection in digital images, this paper studied traditional methods and algorithm based on SVM. It analyzed Canny edge detection algorithm existed some pseudo-edge and poor anti-noise capability. In order to provide a reliable edge extraction method, propose a new detection algorithm based on FSVM. Which contains several steps: first, trains classify sample and gives the different membership function to different samples. Then, a new training sample is formed by increase the punishment some wrong sub-sample, and use the new FSVM classification model for train and test them. Finally the edges are extracted of the object image by using the model. Experimental result shows that good edge detection image will be obtained and adding noise experiments results show that this method has good anti-noise.

  14. Fall detection algorithm in energy efficient multistate sensor system.

    PubMed

    Korats, Gundars; Hofmanis, Janis; Skorodumovs, Aleksejs; Avots, Egils

    2015-01-01

    Health issues for elderly people may lead to different injuries obtained during simple activities of daily living (ADL). Potentially the most dangerous are unintentional falls that may be critical or even lethal to some patients due to the heavy injury risk. Many fall detection systems are proposed but only recently such health care systems became available. Nevertheless sensor design, accuracy as well as energy consumption efficiency can be improved. In this paper we present a single 3-axial accelerometer energy-efficient sensor system. Power saving is achieved by selective event processing triggered by fall detection procedure. The results in our simulations show 100% accuracy when the threshold parameters are chosen correctly. Estimated energy consumption seems to extend battery life significantly. PMID:26737408

  15. High resolution PET breast imager with improved detection efficiency

    DOEpatents

    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.

  16. Efficient detection of brown dwarfs using methane-band imaging

    NASA Astrophysics Data System (ADS)

    Rosenthal, Edward D.; Gurwell, Mark A.; Ho, Paul T. P.

    1996-11-01

    BROWN dwarfs lie in the mass range between the most massive Jupiter-like planets and the least massive stars. They are much less luminous than stars, and so may provide a fraction of the baryonic dark matter in our Galaxy. Only one unambiguous detection of a brown dwarf has been made to date1-6-G1229B, a low-mass companion to the nearby star G1229A. The detection4 of strong methane-band absorption in the spectrum of G1229B, a feature restricted to cool substellar objects5-9, lends weight to the idea7 that differential methane-band imaging (the subtraction of an image taken in the methane band from a continuum-light image taken in the same spectral region) should provide an efficient method for detecting brown dwarfs. Here we demonstrate the potential of this approach by obtaining an image of G1229B with less than two minutes of integration time. This technique promises efficient detection of both isolated brown dwarfs in crowded regions, and brown dwarfs orbiting close to their primary stars.

  17. Efficient Detection of Pathogenic Leptospires Using 16S Ribosomal RNA

    PubMed Central

    Lindow, Janet; Wunder, Elsio A.; Reis, Mitermayer G.; Usmani-Brown, Sahar; Ledizet, Michel; Ko, Albert; Pal, Utpal

    2015-01-01

    Pathogenic Leptospira species cause a prevalent yet neglected zoonotic disease with mild to life-threatening complications in a variety of susceptible animals and humans. Diagnosis of leptospirosis, which primarily relies on antiquated serotyping methods, is particularly challenging due to presentation of non-specific symptoms shared by other febrile illnesses, often leading to misdiagnosis. Initiation of antimicrobial therapy during early infection to prevent more serious complications of disseminated infection is often not performed because of a lack of efficient diagnostic tests. Here we report that specific regions of leptospiral 16S ribosomal RNA molecules constitute a novel and efficient diagnostic target for PCR-based detection of pathogenic Leptospira serovars. Our diagnostic test using spiked human blood was at least 100-fold more sensitive than corresponding leptospiral DNA-based quantitative PCR assays, targeting the same 16S nucleotide sequence in the RNA and DNA molecules. The sensitivity and specificity of our RNA assay against laboratory-confirmed human leptospirosis clinical samples were 64% and 100%, respectively, which was superior then an established parallel DNA detection assay. Remarkably, we discovered that 16S transcripts remain appreciably stable ex vivo, including untreated and stored human blood samples, further highlighting their use for clinical detection of L. interrogans. Together, these studies underscore a novel utility of RNA targets, specifically 16S rRNA, for development of PCR-based modalities for diagnosis of human leptospirosis, and also may serve as paradigm for detection of additional bacterial pathogens for which early diagnosis is warranted. PMID:26091292

  18. Estimation of extrinsic detection efficiency using intrinsic detection sensitivity of the commercial single photon detector

    NASA Astrophysics Data System (ADS)

    Hammura, Kiyotaka; Xu, Xiulai; Brossard, Frederic; Williams, David

    2009-03-01

    The detection efficiency (DE) of the commercial single-photon-receiver based on InGaAs gate-mode avalanche photodiode is estimated using the detection sensitivity (DS). Instalment of a digital-blanking-system (DBS) to reduce dark current makes the difference between DS, which is an efficiency of the detector during its open-gate/active state, and the total/overall detection efficiency (DE). By numerical simulations, it is found that the average number of light-pulses, blanked by DBS, following a registered pulse is 0.333. DS is estimated at 0.216, which can be used for estimating DE for an arbitrary photon arriving rate and a gating frequency of the receiver.

  19. Fast and Computationally Efficient Boundary Detection Technique for Medical Images

    NASA Astrophysics Data System (ADS)

    Das, Arpita; Goswami, Partha; Sen, Susanta

    2011-03-01

    Detection of edge is a fundamental procedure of image processing. Many edge detection algorithms have been developed based on computation of the intensity gradient. In medical images, boundaries of the objects are vague for gradual change of intensities. Therefore need exists to develop a computationally efficient and accurate edge detection approach. We have presented such algorithm using modified global threshold technique. In our work, the boundaries are highlighted from the background by selecting a threshold (T) that separates object and background. In the image, where object to background or vice-verse transition occurs, pixel intensity either rises greater or equal to T (background to object transition) or falls less than T (object to background). We have marked these transition regions as object boundary and enhanced the corresponding intensity. The value of T may be specified heuristically or by following specific algorithm. Conventional global threshold algorithm computes the value of T automatically. But this approach is not computationally efficient and required a large memory. In this study, we have proposed a parameter for which computation of T is very easy and fast. We have also proved that a fixed size memory [ 256 × 4 Byte] is enough to compute this algorithm.

  20. Active link selection for efficient semi-supervised community detection.

    PubMed

    Yang, Liang; Jin, Di; Wang, Xiao; Cao, Xiaochun

    2015-01-01

    Several semi-supervised community detection algorithms have been proposed recently to improve the performance of traditional topology-based methods. However, most of them focus on how to integrate supervised information with topology information; few of them pay attention to which information is critical for performance improvement. This leads to large amounts of demand for supervised information, which is expensive or difficult to obtain in most fields. For this problem we propose an active link selection framework, that is we actively select the most uncertain and informative links for human labeling for the efficient utilization of the supervised information. We also disconnect the most likely inter-community edges to further improve the efficiency. Our main idea is that, by connecting uncertain nodes to their community hubs and disconnecting the inter-community edges, one can sharpen the block structure of adjacency matrix more efficiently than randomly labeling links as the existing methods did. Experiments on both synthetic and real networks demonstrate that our new approach significantly outperforms the existing methods in terms of the efficiency of using supervised information. It needs ~13% of the supervised information to achieve a performance similar to that of the original semi-supervised approaches. PMID:25761385

  1. Improvement of the Error-detection Mechanism in Adults with Dyslexia Following Reading Acceleration Training.

    PubMed

    Horowitz-Kraus, Tzipi

    2016-05-01

    The error-detection mechanism aids in preventing error repetition during a given task. Electroencephalography demonstrates that error detection involves two event-related potential components: error-related and correct-response negativities (ERN and CRN, respectively). Dyslexia is characterized by slow, inaccurate reading. In particular, individuals with dyslexia have a less active error-detection mechanism during reading than typical readers. In the current study, we examined whether a reading training programme could improve the ability to recognize words automatically (lexical representations) in adults with dyslexia, thereby resulting in more efficient error detection during reading. Behavioural and electrophysiological measures were obtained using a lexical decision task before and after participants trained with the reading acceleration programme. ERN amplitudes were smaller in individuals with dyslexia than in typical readers before training but increased following training, as did behavioural reading scores. Differences between the pre-training and post-training ERN and CRN components were larger in individuals with dyslexia than in typical readers. Also, the error-detection mechanism as represented by the ERN/CRN complex might serve as a biomarker for dyslexia and be used to evaluate the effectiveness of reading intervention programmes. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Improvement of the Error-detection Mechanism in Adults with Dyslexia Following Reading Acceleration Training.

    PubMed

    Horowitz-Kraus, Tzipi

    2016-05-01

    The error-detection mechanism aids in preventing error repetition during a given task. Electroencephalography demonstrates that error detection involves two event-related potential components: error-related and correct-response negativities (ERN and CRN, respectively). Dyslexia is characterized by slow, inaccurate reading. In particular, individuals with dyslexia have a less active error-detection mechanism during reading than typical readers. In the current study, we examined whether a reading training programme could improve the ability to recognize words automatically (lexical representations) in adults with dyslexia, thereby resulting in more efficient error detection during reading. Behavioural and electrophysiological measures were obtained using a lexical decision task before and after participants trained with the reading acceleration programme. ERN amplitudes were smaller in individuals with dyslexia than in typical readers before training but increased following training, as did behavioural reading scores. Differences between the pre-training and post-training ERN and CRN components were larger in individuals with dyslexia than in typical readers. Also, the error-detection mechanism as represented by the ERN/CRN complex might serve as a biomarker for dyslexia and be used to evaluate the effectiveness of reading intervention programmes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27072047

  3. On the Detection of Energetically Efficient Trajectories for Spacecraft

    NASA Technical Reports Server (NTRS)

    Dellnitz, Michael; Junge, Oliver; Lo, Martin; Thiere, Bianca

    2001-01-01

    We propose a new method for the detection of energy-efficient trajectories for spacecraft. Via a so called target-shooting approach a pseudo-orbit between the relevant points in space is constructed in a simple model of the problem. This approximate trajectory is meant to serve as input for a more sophisticated direct method in order to compute a true trajectory in the full model. We demonstrate the applicability of the new method by considering the redesign of part of the trajectory of the NASA/JPL Genesis discovery mission.

  4. Efficient implementations of hyperspectral chemical-detection algorithms

    NASA Astrophysics Data System (ADS)

    Brett, Cory J. C.; DiPietro, Robert S.; Manolakis, Dimitris G.; Ingle, Vinay K.

    2013-10-01

    Many military and civilian applications depend on the ability to remotely sense chemical clouds using hyperspectral imagers, from detecting small but lethal concentrations of chemical warfare agents to mapping plumes in the aftermath of natural disasters. Real-time operation is critical in these applications but becomes diffcult to achieve as the number of chemicals we search for increases. In this paper, we present efficient CPU and GPU implementations of matched-filter based algorithms so that real-time operation can be maintained with higher chemical-signature counts. The optimized C++ implementations show between 3x and 9x speedup over vectorized MATLAB implementations.

  5. Efficient measurement-device-independent detection of multipartite entanglement structure

    NASA Astrophysics Data System (ADS)

    Zhao, Qi; Yuan, Xiao; Ma, Xiongfeng

    2016-07-01

    Witnessing entanglement is crucial in quantum information processing. With properly preparing ancillary states, it has been shown previously that genuine entanglement can be witnessed without trusting measurement devices. In this work we generalize the scenario and show that generic multipartite entanglement structures, including entanglement of subsystems and entanglement depth, can be witnessed via measurement-device-independent means. As the original measurement-device-independent entanglement witness scheme exploits only one out of four Bell measurement outcomes for each party, a direct generalization to multipartite quantum states will inevitably cause inefficiency in entanglement detection after taking account of statistical fluctuations. To resolve this problem, we also present a way to utilize all the measurement outcomes. The scheme is efficient for multipartite entanglement detection and can be realized with state-of-the-art technologies.

  6. Computationally efficient strategies to perform anomaly detection in hyperspectral images

    NASA Astrophysics Data System (ADS)

    Rossi, Alessandro; Acito, Nicola; Diani, Marco; Corsini, Giovanni

    2012-11-01

    In remote sensing, hyperspectral sensors are effectively used for target detection and recognition because of their high spectral resolution that allows discrimination of different materials in the sensed scene. When a priori information about the spectrum of the targets of interest is not available, target detection turns into anomaly detection (AD), i.e. searching for objects that are anomalous with respect to the scene background. In the field of AD, anomalies can be generally associated to observations that statistically move away from background clutter, being this latter intended as a local neighborhood surrounding the observed pixel or as a large part of the image. In this context, many efforts have been put to reduce the computational load of AD algorithms so as to furnish information for real-time decision making. In this work, a sub-class of AD methods is considered that aim at detecting small rare objects that are anomalous with respect to their local background. Such techniques not only are characterized by mathematical tractability but also allow the design of real-time strategies for AD. Within these methods, one of the most-established anomaly detectors is the RX algorithm which is based on a local Gaussian model for background modeling. In the literature, the RX decision rule has been employed to develop computationally efficient algorithms implemented in real-time systems. In this work, a survey of computationally efficient methods to implement the RX detector is presented where advanced algebraic strategies are exploited to speed up the estimate of the covariance matrix and of its inverse. The comparison of the overall number of operations required by the different implementations of the RX algorithms is given and discussed by varying the RX parameters in order to show the computational improvements achieved with the introduced algebraic strategy.

  7. Processing speed training increases the efficiency of attentional resource allocation in young adults.

    PubMed

    Burge, Wesley K; Ross, Lesley A; Amthor, Franklin R; Mitchell, William G; Zotov, Alexander; Visscher, Kristina M

    2013-01-01

    Cognitive training has been shown to improve performance on a range of tasks. However, the mechanisms underlying these improvements are still unclear. Given the wide range of transfer effects, it is likely that these effects are due to a factor common to a wide range of tasks. One such factor is a participant's efficiency in allocating limited cognitive resources. The impact of a cognitive training program, Processing Speed Training (PST), on the allocation of resources to a set of visual tasks was measured using pupillometry in 10 young adults as compared to a control group of a 10 young adults (n = 20). PST is a well-studied computerized training program that involves identifying simultaneously presented central and peripheral stimuli. As training progresses, the task becomes increasingly more difficult, by including peripheral distracting stimuli and decreasing the duration of stimulus presentation. Analysis of baseline data confirmed that pupil diameter reflected cognitive effort. After training, participants randomized to PST used fewer attentional resources to perform complex visual tasks as compared to the control group. These pupil diameter data indicated that PST appears to increase the efficiency of attentional resource allocation. Increases in cognitive efficiency have been hypothesized to underlie improvements following experience with action video games, and improved cognitive efficiency has been hypothesized to underlie the benefits of PST in older adults. These data reveal that these training schemes may share a common underlying mechanism of increasing cognitive efficiency in younger adults. PMID:24151461

  8. Efficient detection of contagious outbreaks in massive metropolitan encounter networks.

    PubMed

    Sun, Lijun; Axhausen, Kay W; Lee, Der-Horng; Cebrian, Manuel

    2014-01-01

    Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the "friend sensor" scheme--a simple, but universal strategy requiring only local information--and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced "global sensor sets", obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree. PMID:24903017

  9. Efficient detection of contagious outbreaks in massive metropolitan encounter networks

    PubMed Central

    Sun, Lijun; Axhausen, Kay W.; Lee, Der-Horng; Cebrian, Manuel

    2014-01-01

    Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the “friend sensor” scheme - a simple, but universal strategy requiring only local information - and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced “global sensor sets”, obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree. PMID:24903017

  10. Efficient detection of contagious outbreaks in massive metropolitan encounter networks.

    PubMed

    Sun, Lijun; Axhausen, Kay W; Lee, Der-Horng; Cebrian, Manuel

    2014-06-06

    Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the "friend sensor" scheme--a simple, but universal strategy requiring only local information--and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced "global sensor sets", obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree.

  11. Older adults utilize less efficient postural control when performing pushing task.

    PubMed

    Lee, Yun-Ju; Chen, Bing; Aruin, Alexander S

    2015-12-01

    The ability to maintain balance deteriorates with increasing age. The aim was to investigate the role of age in generation of anticipatory (APA) and compensatory (CPA) postural adjustments during pushing an object. Older (68.8 ± 1.0 years) and young adults (30.1 ± 1.4 years) participated in the experiment involving pushing an object (a pendulum attached to the ceiling) using both hands. Electrical activity of six leg and trunk muscles and displacements of the center of pressure (COP) were recorded and analyzed during the APA and CPA phases. The onset time, integrals of muscle activity, and COP displacements were determined. In addition, the indexes of co-activation and reciprocal activation of muscles for the shank, thigh, and trunk segments were calculated. Older adults, compared to young adults, showed less efficient postural control seen as delayed anticipatory muscle onset times and delayed COP displacements. Moreover, older adults used co-activation of muscles during the CPA phase while younger subjects utilized reciprocal activation of muscles. The observed diminished efficiency of postural control during both anticipatory and compensatory postural adjustments observed in older adults might predispose them to falls while performing tasks involving pushing. The outcome provides a background for future studies focused on the optimization of the daily activities of older adults.

  12. Development of sampling efficiency and internal noise in motion detection and discrimination in school-aged children.

    PubMed

    Falkenberg, Helle K; Simpson, William A; Dutton, Gordon N

    2014-07-01

    The aim of this study was to use an equivalent noise paradigm to investigate the development and maturation of motion perception, and how the underlying limitations of sampling efficiency and internal noise effect motion detection and direction discrimination in school-aged children (5-14 years) and adults. Contrast energy thresholds of a 2c/deg sinusoidal grating drifting at 1.0 or 6.0 Hz were measured as a function of added dynamic noise in three tasks: detection of a drifting grating; detection of the sum of two oppositely drifting gratings and direction discrimination of oppositely drifting gratings. Compared to the ideal observer, in both children and adults, the performance for all tasks was limited by reduced sampling efficiency and internal noise. However, the thresholds for discrimination of motion direction and detection of moving gratings show very different developmental profiles. Motion direction discrimination continues to improve after the age of 14 years due to an increase in sampling efficiency that differs with speed. Motion detection and summation were already mature at the age of 5 years, and internal noise was the same for all tasks. These findings were confirmed in a 1-year follow-up study on a group of children from the initial study. The results support suggestions that the detection of a moving pattern and discriminating motion direction are processed by different systems that may develop at different rates.

  13. Efficiently detecting outlying behavior in video-game players.

    PubMed

    Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo; Kim, Chang Hun

    2015-01-01

    In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players' characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments. PMID:26713250

  14. Efficiently detecting outlying behavior in video-game players.

    PubMed

    Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo; Kim, Chang Hun

    2015-01-01

    In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players' characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

  15. Efficiently detecting outlying behavior in video-game players

    PubMed Central

    Kim, Young Bin; Kang, Shin Jin; Lee, Sang Hyeok; Jung, Jang Young; Kam, Hyeong Ryeol; Lee, Jung; Kim, Young Sun; Lee, Joonsoo

    2015-01-01

    In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players’ characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments. PMID:26713250

  16. Meckel's diverticulum: pitfalls in scintigraphic detection in the adult

    SciTech Connect

    Schwartz, M.J.; Lewis, J.H.

    1984-08-01

    The diagnosis of a bleeding Meckel's diverticulum containing ectopic gastric mucosa by 99m-Tc pertechnetate imaging is reported to have a diagnostic accuracy of 90% for patients in the pediatric age group. The usefulness of Meckel's scanning in adults is, however, less certain. We present two patients who illustrate some of the difficulties inherent in Meckel's scanning in adults; one had a false-negative scan despite the presence of ectopic gastric mucosa and the other had a false-positive scan, both confirmed by laparotomy. The available literature indicates that false-positive and false-negative scans occur relatively frequently in adults, but no comprehensive review on this subject exists. Based on our findings, it is suggested that Meckel's scanning be supplemented with small bowel infusion or arteriography or both to improve preoperative diagnosis in adult patients in whom a diverticulum is suspected.

  17. Extreme ultraviolet quantum detection efficiency of rubidium bromide opaque photocathodes

    NASA Technical Reports Server (NTRS)

    Siegmund, Oswald H. W.; Gaines, Geoffrey A.

    1990-01-01

    Measurements are presented of the quantum detection efficiency (QDE) of three samples of RbBr photocathode layers over the 44-150-A wavelength range. The QDE of RbBr-coated microchannel plate (MCP) was measured using a back-to-back Z-stack MCP configuration in a detector with a wedge and strip position-sensitive anode, of the type described by Siegmund et al. (1984). To assess the stability of RbBr layer, the RbBr photocathode was exposed to air at about 30 percent humidity for 20 hr. It was found that the QDE values for the aged cathode were within the QDE measurement errors of the original values. A simple QDE model was developed, and it was found that its predictions are in accord with the QDE measurements.

  18. Hardware Design of the Energy Efficient Fall Detection Device

    NASA Astrophysics Data System (ADS)

    Skorodumovs, A.; Avots, E.; Hofmanis, J.; Korāts, G.

    2016-04-01

    Health issues for elderly people may lead to different injuries obtained during simple activities of daily living. Potentially the most dangerous are unintentional falls that may be critical or even lethal to some patients due to the heavy injury risk. In the project "Wireless Sensor Systems in Telecare Application for Elderly People", we have developed a robust fall detection algorithm for a wearable wireless sensor. To optimise the algorithm for hardware performance and test it in field, we have designed an accelerometer based wireless fall detector. Our main considerations were: a) functionality - so that the algorithm can be applied to the chosen hardware, and b) power efficiency - so that it can run for a very long time. We have picked and tested the parts, built a prototype, optimised the firmware for lowest consumption, tested the performance and measured the consumption parameters. In this paper, we discuss our design choices and present the results of our work.

  19. Correlation based efficient face recognition and color change detection

    NASA Astrophysics Data System (ADS)

    Elbouz, M.; Alfalou, A.; Brosseau, C.; Alam, M. S.; Qasmi, S.

    2013-01-01

    Identifying the human face via correlation is a topic attracting widespread interest. At the heart of this technique lies the comparison of an unknown target image to a known reference database of images. However, the color information in the target image remains notoriously difficult to interpret. In this paper, we report a new technique which: (i) is robust against illumination change, (ii) offers discrimination ability to detect color change between faces having similar shape, and (iii) is specifically designed to detect red colored stains (i.e. facial bleeding). We adopt the Vanderlugt correlator (VLC) architecture with a segmented phase filter and we decompose the color target image using normalized red, green, and blue (RGB), and hue, saturation, and value (HSV) scales. We propose a new strategy to effectively utilize color information in signatures for further increasing the discrimination ability. The proposed algorithm has been found to be very efficient for discriminating face subjects with different skin colors, and those having color stains in different areas of the facial image.

  20. An Efficient Conflict Detection Algorithm for Packet Filters

    NASA Astrophysics Data System (ADS)

    Lee, Chun-Liang; Lin, Guan-Yu; Chen, Yaw-Chung

    Packet classification is essential for supporting advanced network services such as firewalls, quality-of-service (QoS), virtual private networks (VPN), and policy-based routing. The rules that routers use to classify packets are called packet filters. If two or more filters overlap, a conflict occurs and leads to ambiguity in packet classification. This study proposes an algorithm that can efficiently detect and resolve filter conflicts using tuple based search. The time complexity of the proposed algorithm is O(nW+s), and the space complexity is O(nW), where n is the number of filters, W is the number of bits in a header field, and s is the number of conflicts. This study uses the synthetic filter databases generated by ClassBench to evaluate the proposed algorithm. Simulation results show that the proposed algorithm can achieve better performance than existing conflict detection algorithms both in time and space, particularly for databases with large numbers of conflicts.

  1. Wavelet decomposition-based efficient face liveness detection

    NASA Astrophysics Data System (ADS)

    Moniruzzaman, Md.; Alam, Mohammad S.

    2016-04-01

    Existing face recognition systems are susceptible to spoofing attacks. So, Face liveness detection is a pivotal part for reliable face recognition, which has recently acknowledged vast attention. In this paper we propose a wavelet decomposition based face liveness recognition system using an energy calculation technique. Live faces contain high energy components compared to fake or printed image. In this paper, we calculate energy components of live face as well as fake face using discrete wavelet decomposition method. We analyze percentage of energy at different levels as well as for different wavelet basis function. We also analyze percentage of energy at different RGB bands and efficient face liveness detection method has been proposed. Discrete wavelet representation has been used to calculate decomposed energy components. Moreover, it provides differentiation of several spatial orientations as well as average and detailed information which are missing in the fake faces. This technique provides excellent discrimination capability when compared to the previously reported works based on the discrete Fourier transform and n-dimensional Fourier transform operations. To verify the proposed approach, we tested the performance using various face antispoofing datasets such as university of south Alabama (UFAD), and MSU face antispoofing dataset which incorporates different types of attacks. The test results obtained using the proposed technique shows better performance compared to existing techniques.

  2. Efficient vessel feature detection for endoscopic image analysis.

    PubMed

    Lin, Bingxiong; Sun, Yu; Sanchez, Jaime E; Qian, Xiaoning

    2015-04-01

    Distinctive feature detection is an essential task in computer-assisted minimally invasive surgery (MIS). For special conditions in an MIS imaging environment, such as specular reflections and texture homogeneous areas, the feature points extracted by general feature point detectors are less distinctive and repeatable in MIS images. We observe that abundant blood vessels are available on tissue surfaces and can be extracted as a new set of image features. In this paper, two types of blood vessel features are proposed for endoscopic images: branching points and branching segments. Two novel methods, ridgeness-based circle test and ridgeness-based branching segment detection are presented to extract branching points and branching segments, respectively. Extensive in vivo experiments were conducted to evaluate the performance of the proposed methods and compare them with the state-of-the-art methods. The numerical results verify that, in MIS images, the blood vessel features can produce a large number of points.More importantly, those points are more robust and repeatable than the other types of feature points. In addition, due to the difference in feature types, vessel features can be combined with other general features, which makes them new tools for MIS image analysis. These proposed methods are efficient and the code and datasets are made available to the public.

  3. Lightning Detection Efficiency Analysis Process: Modeling Based on Empirical Data

    NASA Technical Reports Server (NTRS)

    Rompala, John T.

    2005-01-01

    A ground based lightning detection system employs a grid of sensors, which record and evaluate the electromagnetic signal produced by a lightning strike. Several detectors gather information on that signal s strength, time of arrival, and behavior over time. By coordinating the information from several detectors, an event solution can be generated. That solution includes the signal s point of origin, strength and polarity. Determination of the location of the lightning strike uses algorithms based on long used techniques of triangulation. Determination of the event s original signal strength relies on the behavior of the generated magnetic field over distance and time. In general the signal from the event undergoes geometric dispersion and environmental attenuation as it progresses. Our knowledge of that radial behavior together with the strength of the signal received by detecting sites permits an extrapolation and evaluation of the original strength of the lightning strike. It also limits the detection efficiency (DE) of the network. For expansive grids and with a sparse density of detectors, the DE varies widely over the area served. This limits the utility of the network in gathering information on regional lightning strike density and applying it to meteorological studies. A network of this type is a grid of four detectors in the Rondonian region of Brazil. The service area extends over a million square kilometers. Much of that area is covered by rain forests. Thus knowledge of lightning strike characteristics over the expanse is of particular value. I have been developing a process that determines the DE over the region [3]. In turn, this provides a way to produce lightning strike density maps, corrected for DE, over the entire region of interest. This report offers a survey of that development to date and a record of present activity.

  4. Rapid Detection of Visually Provocative Animals by Preschool Children and Adults

    ERIC Educational Resources Information Center

    Penkunas, Michael J.; Coss, Richard G.

    2013-01-01

    The ability to detect dangerous animals rapidly in complex landscapes has been historically important during human evolution. Previous research has shown that snake images are more readily detected than images of benign animals. To provide a stringent test of superior snake detection in preschool children and adults, Experiment 1 consisted of two…

  5. Does Faux Pas Detection in Adult Autism Reflect Differences in Social Cognition or Decision-Making Abilities?

    ERIC Educational Resources Information Center

    Thiébaut, Flora I.; White, Sarah J.; Walsh, Annabel; Klargaard, Solja K.; Wu, Hsuan-Chen; Rees, Geraint; Burgess, Paul W.

    2016-01-01

    43 typically-developed adults and 35 adults with ASD performed a cartoon faux pas test. Adults with ASD apparently over-detected faux pas despite good comprehension abilities, and were generally slower at responding. Signal detection analysis demonstrated that the ASD participants had significantly greater difficulty detecting whether a cartoon…

  6. The Effect of Treadmill Exercise on Gait Efficiency During Overground Walking in Adults With Cerebral Palsy

    PubMed Central

    Kim, On-Yoo; Shin, Yoon-Kyum; Yoon, Young Kwon; Ko, Eu Jeong

    2015-01-01

    Objective To investigate the effect of treadmill walking exercise as a treatment method to improve gait efficiency in adults with cerebral palsy (CP) and to determine gait efficiency during overground walking after the treadmill walking exercise. Methods Fourteen adults with CP were recruited in the experimental group of treadmill walking exercise. A control group of 7 adults with CP who attended conventional physical therapy were also recruited. The treadmill walking exercise protocol consisted of 3-5 training sessions per week for 1-2 months (total 20 sessions). Gait distance, velocity, VO2, VCO2, O2 rate (mL/kg·min), and O2 cost (mL/kg·m) were assessed at the beginning and at the end of the treadmill walking exercise. The parameters were measured by KB1-C oximeter. Results After the treadmill walking exercise, gait distance during overground walking up to 6 minutes significantly increased from 151.29±91.79 to 193.93±79.01 m, and gait velocity increased from 28.09±14.29 to 33.49±12.69 m/min (p<0.05). Energy efficiency evaluated by O2 cost during overground walking significantly improved from 0.56±0.36 to 0.41±0.18 mL/kg·m (p<0.05), whereas O2 rate did not improve significantly after the treadmill walking exercise. On the other hand, gait velocity and O2 cost during overground walking were not significantly changed in the control group. Conclusion Treadmill walking exercise improved the gait efficiency by decreased energy expenditure during overground walking in adults with CP. Therefore, treadmill walking exercise can be an important method for gait training in adults with CP who have higher energy expenditure. PMID:25750868

  7. Efficient source separation algorithms for acoustic fall detection using a microsoft kinect.

    PubMed

    Li, Yun; Ho, K C; Popescu, Mihail

    2014-03-01

    Falls have become a common health problem among older adults. In previous study, we proposed an acoustic fall detection system (acoustic FADE) that employed a microphone array and beamforming to provide automatic fall detection. However, the previous acoustic FADE had difficulties in detecting the fall signal in environments where interference comes from the fall direction, the number of interferences exceeds FADE's ability to handle or a fall is occluded. To address these issues, in this paper, we propose two blind source separation (BSS) methods for extracting the fall signal out of the interferences to improve the fall classification task. We first propose the single-channel BSS by using nonnegative matrix factorization (NMF) to automatically decompose the mixture into a linear combination of several basis components. Based on the distinct patterns of the bases of falls, we identify them efficiently and then construct the interference free fall signal. Next, we extend the single-channel BSS to the multichannel case through a joint NMF over all channels followed by a delay-and-sum beamformer for additional ambient noise reduction. In our experiments, we used the Microsoft Kinect to collect the acoustic data in real-home environments. The results show that in environments with high interference and background noise levels, the fall detection performance is significantly improved using the proposed BSS approaches.

  8. Signal Detection Analysis of Factors Associated with Diabetes among Semirural Mexican American Adults

    ERIC Educational Resources Information Center

    Hanni, K. D.; Ahn, D. A.; Winkleby, M. A.

    2013-01-01

    Signal detection analysis was used to evaluate a combination of sociodemographic, acculturation, mental health, health care, and chronic disease risk factors potentially associated with diabetes in a sample of 4,505 semirural Mexican American adults. Overall, 8.9% of adults had been diagnosed with diabetes. The analysis resulted in 12 mutually…

  9. Rapid and efficient gene delivery into the adult mouse brain via focal electroporation

    PubMed Central

    Nomura, Tadashi; Nishimura, Yusuke; Gotoh, Hitoshi; Ono, Katsuhiko

    2016-01-01

    In vivo gene delivery is required for studying the cellular and molecular mechanisms of various biological events. Virus-mediated gene transfer or generation of transgenic animals is widely used; however, these methods are time-consuming and expensive. Here we show an improved electroporation technique for acute gene delivery into the adult mouse brain. Using a syringe-based microelectrode, local DNA injection and the application of electric current can be performed simultaneously; this allows rapid and efficient gene transduction of adult non-neuronal cells. Combining this technique with various expression vectors that carry specific promoters resulted in targeted gene expression in astrocytic cells. Our results constitute a powerful strategy for the genetic manipulation of adult brains in a spatio-temporally controlled manner. PMID:27430903

  10. Rapid and efficient gene delivery into the adult mouse brain via focal electroporation.

    PubMed

    Nomura, Tadashi; Nishimura, Yusuke; Gotoh, Hitoshi; Ono, Katsuhiko

    2016-01-01

    In vivo gene delivery is required for studying the cellular and molecular mechanisms of various biological events. Virus-mediated gene transfer or generation of transgenic animals is widely used; however, these methods are time-consuming and expensive. Here we show an improved electroporation technique for acute gene delivery into the adult mouse brain. Using a syringe-based microelectrode, local DNA injection and the application of electric current can be performed simultaneously; this allows rapid and efficient gene transduction of adult non-neuronal cells. Combining this technique with various expression vectors that carry specific promoters resulted in targeted gene expression in astrocytic cells. Our results constitute a powerful strategy for the genetic manipulation of adult brains in a spatio-temporally controlled manner. PMID:27430903

  11. Detection of Sound Rise Time by Adults with Dyslexia

    ERIC Educational Resources Information Center

    Hamalainen, J.; Leppanen, P.H.T.; Torppa, M.; Muller, K.; Lyytinen, H.

    2005-01-01

    Low sensitivity to amplitude modulated (AM) sounds is reported to be associated with dyslexia. An important aspect of amplitude modulation cycles are the rise and fall times within the sound. In this study, simplified stimuli equivalent to just one cycle were used and sensitivity to varying rise times was explored. Adult participants with dyslexia…

  12. Effects of image processing on the detective quantum efficiency

    NASA Astrophysics Data System (ADS)

    Park, Hye-Suk; Kim, Hee-Joung; Cho, Hyo-Min; Lee, Chang-Lae; Lee, Seung-Wan; Choi, Yu-Na

    2010-04-01

    Digital radiography has gained popularity in many areas of clinical practice. This transition brings interest in advancing the methodologies for image quality characterization. However, as the methodologies for such characterizations have not been standardized, the results of these studies cannot be directly compared. The primary objective of this study was to standardize methodologies for image quality characterization. The secondary objective was to evaluate affected factors to Modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) according to image processing algorithm. Image performance parameters such as MTF, NPS, and DQE were evaluated using the international electro-technical commission (IEC 62220-1)-defined RQA5 radiographic techniques. Computed radiography (CR) images of hand posterior-anterior (PA) for measuring signal to noise ratio (SNR), slit image for measuring MTF, white image for measuring NPS were obtained and various Multi-Scale Image Contrast Amplification (MUSICA) parameters were applied to each of acquired images. In results, all of modified images were considerably influence on evaluating SNR, MTF, NPS, and DQE. Modified images by the post-processing had higher DQE than the MUSICA=0 image. This suggests that MUSICA values, as a post-processing, have an affect on the image when it is evaluating for image quality. In conclusion, the control parameters of image processing could be accounted for evaluating characterization of image quality in same way. The results of this study could be guided as a baseline to evaluate imaging systems and their imaging characteristics by measuring MTF, NPS, and DQE.

  13. Cerebroventricular Microinjection (CVMI) into Adult Zebrafish Brain Is an Efficient Misexpression Method for Forebrain Ventricular Cells

    PubMed Central

    Kizil, Caghan; Brand, Michael

    2011-01-01

    The teleost fish Danio rerio (zebrafish) has a remarkable ability to generate newborn neurons in its brain at adult stages of its lifespan-a process called adult neurogenesis. This ability relies on proliferating ventricular progenitors and is in striking contrast to mammalian brains that have rather restricted capacity for adult neurogenesis. Therefore, investigating the zebrafish brain can help not only to elucidate the molecular mechanisms of widespread adult neurogenesis in a vertebrate species, but also to design therapies in humans with what we learn from this teleost. Yet, understanding the cellular behavior and molecular programs underlying different biological processes in the adult zebrafish brain requires techniques that allow manipulation of gene function. As a complementary method to the currently used misexpression techniques in zebrafish, such as transgenic approaches or electroporation-based delivery of DNA, we devised a cerebroventricular microinjection (CVMI)-assisted knockdown protocol that relies on vivo morpholino oligonucleotides, which do not require electroporation for cellular uptake. This rapid method allows uniform and efficient knockdown of genes in the ventricular cells of the zebrafish brain, which contain the neurogenic progenitors. We also provide data on the use of CVMI for growth factor administration to the brain – in our case FGF8, which modulates the proliferation rate of the ventricular cells. In this paper, we describe the CVMI method and discuss its potential uses in zebrafish. PMID:22076157

  14. Color is processed less efficiently than orientation in change detection but more efficiently in visual search.

    PubMed

    Huang, Liqiang

    2015-05-01

    Basic visual features (e.g., color, orientation) are assumed to be processed in the same general way across different visual tasks. Here, a significant deviation from this assumption was predicted on the basis of the analysis of stimulus spatial structure, as characterized by the Boolean-map notion. If a task requires memorizing the orientations of a set of bars, then the map consisting of those bars can be readily used to hold the overall structure in memory and will thus be especially useful. If the task requires visual search for a target, then the map, which contains only an overall structure, will be of little use. Supporting these predictions, the present study demonstrated that in comparison to stimulus colors, bar orientations were processed more efficiently in change-detection tasks but less efficiently in visual search tasks (Cohen's d = 4.24). In addition to offering support for the role of the Boolean map in conscious access, the present work also throws doubts on the generality of processing visual features.

  15. Position-Dependent Local Detection Efficiency in a Nanowire Superconducting Single-Photon Detector.

    PubMed

    Renema, J J; Wang, Q; Gaudio, R; Komen, I; op 't Hoog, K; Sahin, D; Schilling, A; van Exter, M P; Fiore, A; Engel, A; de Dood, M J A

    2015-07-01

    We probe the local detection efficiency in a nanowire superconducting single-photon detector along the cross-section of the wire with a far subwavelength resolution. We experimentally find a strong variation in the local detection efficiency of the device. We demonstrate that this effect explains previously observed variations in NbN detector efficiency as a function of device geometry. PMID:26087352

  16. Differentiated cells are more efficient than adult stem cells for cloning by somatic cell nuclear transfer.

    PubMed

    Sung, Li-Ying; Gao, Shaorong; Shen, Hongmei; Yu, Hui; Song, Yifang; Smith, Sadie L; Chang, Ching-Chien; Inoue, Kimiko; Kuo, Lynn; Lian, Jin; Li, Ao; Tian, X Cindy; Tuck, David P; Weissman, Sherman M; Yang, Xiangzhong; Cheng, Tao

    2006-11-01

    Since the creation of Dolly via somatic cell nuclear transfer (SCNT), more than a dozen species of mammals have been cloned using this technology. One hypothesis for the limited success of cloning via SCNT (1%-5%) is that the clones are likely to be derived from adult stem cells. Support for this hypothesis comes from the findings that the reproductive cloning efficiency for embryonic stem cells is five to ten times higher than that for somatic cells as donors and that cloned pups cannot be produced directly from cloned embryos derived from differentiated B and T cells or neuronal cells. The question remains as to whether SCNT-derived animal clones can be derived from truly differentiated somatic cells. We tested this hypothesis with mouse hematopoietic cells at different differentiation stages: hematopoietic stem cells, progenitor cells and granulocytes. We found that cloning efficiency increases over the differentiation hierarchy, and terminally differentiated postmitotic granulocytes yield cloned pups with the greatest cloning efficiency.

  17. Flash Detection Efficiencies of Long Range Lightning Detection Networks During GRIP

    NASA Technical Reports Server (NTRS)

    Mach, Douglas M.; Bateman, Monte G.; Blakeslee, Richard J.

    2012-01-01

    We flew our Lightning Instrument Package (LIP) on the NASA Global Hawk as a part of the Genesis and Rapid Intensification Processes (GRIP) field program. The GRIP program was a NASA Earth science field experiment during the months of August and September, 2010. During the program, the LIP detected lighting from 48 of the 213 of the storms overflown by the Global Hawk. The time and location of tagged LIP flashes can be used as a "ground truth" dataset for checking the detection efficiency of the various long or extended range ground-based lightning detection systems available during the GRIP program. The systems analyzed included Vaisala Long Range (LR), Vaisala GLD360, the World Wide Lightning Location Network (WWLLN), and the Earth Networks Total Lightning Network (ENTLN). The long term goal of our research is to help understand the advantages and limitations of these systems so that we can utilize them for both proxy data applications and cross sensor validation of the GOES-R Geostationary Lightning Mapper (GLM) sensor when it is launched in the 2015 timeframe.

  18. Improvements in the detection efficiency model for the Brazilian lightning detection network (BrasilDAT)

    NASA Astrophysics Data System (ADS)

    Naccarato, K. P.; Pinto, O., Jr.

    2009-02-01

    The detection efficiency (DE) is the most important performance gauge of a lightning detection network (LDN). Moreover, the main motivation for evaluating the DE of a LDN is to separate the geographical variations of the CG lightning parameters from the variations regarding the network performance. A review of previous relative DE techniques and simple methods to correct the cloud-to-ground (CG) lightning flash density maps is presented. In addition, recent improvements in the flash DE model for the Brazilian lightning detection network (BrasilDAT) are discussed. The DE estimated values are based on the sensor individual DE probability functions, which are derived from a large amount of CG stroke data provided by the network considering different distances from the sensor and specific peak current ranges. The new approach provides better results when compared with the previous developments, since the calculation of the sensor DE probability functions neglects the lightning data provided by the minimum number of reporting sensors. Hence it is possible to minimize the unrealistic enhancement of the DE closer to the network boundaries ("border effect") without affecting significantly the performance inside the network. The main result is a more realistic correction of the CG flash density maps, particularly at the outermost network areas, leading to an improvement in the model sensitivity.

  19. Fearful Face Detection Sensitivity in Healthy Adults Correlates with Anxiety-Related Traits

    PubMed Central

    Doty, Tracy J.; Japee, Shruti; Ingvar, Martin; Ungerleider, Leslie G.

    2014-01-01

    Threatening faces have a privileged status in the brain, which can be reflected in a processing advantage. However, this effect varies among individuals, even healthy adults. For example, one recent study showed that fearful face detection sensitivity correlated with trait anxiety in healthy adults (Japee, Crocker, Carver, Pessoa, & Ungerleider, 2009). Here, we expanded upon those findings by investigating whether intersubject variability in fearful face detection is also associated with state anxiety, as well as more broadly with other traits related to anxiety. To measure fearful face detection sensitivity, we employed a masked face paradigm where the target face was presented for only 33 ms and was immediately followed by a neutral face mask. Subjects then rated their confidence in detecting either fear or no fear in the target face. Fearful face detection sensitivity was calculated for each subject using signal detection theory. Replicating previous results, we found a significant positive correlation between trait anxiety and fearful face detection sensitivity. However, this behavioral advantage did not correlate with state anxiety. We also found that fearful face detection sensitivity correlated with other personality measures, including neuroticism and harm avoidance. Our data suggest that fearful face detection sensitivity varies parametrically across the healthy population, is associated broadly with personality traits related to anxiety, but remains largely unaffected by situational fluctuations in anxiety. These results underscore the important contribution of anxiety-related personality traits to threat processing in healthy adults. PMID:23398584

  20. Need for an efficient adult trap for the surveillance of dengue vectors

    PubMed Central

    Sivagnaname, N.; Gunasekaran, K.

    2012-01-01

    The emergence and re-emergence of arboviral diseases transmitted by Aedes aegypti and Ae. albopictus continue to be a major threat in the tropics and subtropics. Associations between currently used indices and dengue transmission have not been proven to be satisfactorily predictive of dengue epidemics. Classical larval indices in dengue surveillance have limited use in assessing transmission risk and are a poor proxy for measuring adult emergence. Besides, collection of larval indices is labour intensive and plagued by difficulties of access particularly in urban settings. The re-emergence of dengue disease in many countries despite lower immature indices has warranted the need for more effective indices in dengue vector surveillance and control. Reliable and highly useful indices could be developed with the help of efficient and appropriate entomological tools. Most current programmes emphasize reduction of immature Ae. aegypti density, but it is of little value because its relation to transmission risk is weak. More attention should be paid to methods directed toward adult rather than immature Ae. aegypti. Collection of sufficient numbers of adult mosquitoes is important to understand disease transmission dynamics and to devise an appropriate control strategy. Even though, use of certain traps such as BG-Sentinel traps has been attempted in monitoring Ae. aegypti population, their utility is limited due to various setbacks which make these insufficient for entomological and epidemiological studies. Thus, there is an urgent need for the development of an ideal trap that could be used for adult vector surveillance. The present review critically analyzes the setbacks in the existing tools of entomological surveillance of dengue vectors and highlights the importance and necessity of more improved, more sensitive and reliable adult trap that could be used for surveillance of dengue vectors. PMID:23287120

  1. The utility of IFS (INECO Frontal Screening) for the detection of executive dysfunction in adults with bipolar disorder and ADHD.

    PubMed

    Baez, Sandra; Ibanez, Agustin; Gleichgerrcht, Ezequiel; Perez, Ana; Roca, María; Manes, Facundo; Torralva, Teresa

    2014-05-15

    Bipolar disorder (BD) and attention deficit hyperactivity disorder (ADHD) in adults share clinical symptoms. Both disorders present with executive functioning impairment. The detection of executive dysfunction usually requires the administration of an extensive neuropsychological battery. The Institute of Cognitive Neurology (INECO) Frontal Screening (IFS) is an efficient tool, which has been demonstrated to be useful for the detection of executive deficits in other diseases involving the prefrontal cortex. This study assessed the usefulness of the IFS in detecting the executive dysfunction of BD and ADHD adults, by means of a receiver-operating characteristic curve analysis and a multigroup discriminant function analysis. Twenty-four BD, 25 ADHD patients and 25 controls were assessed with a battery that included the IFS and other measures of executive functioning. Our results showed that both patient groups performed significantly lower than controls on the IFS total score. Using a 27.5 point cut-off score, the IFS showed good sensitivity and acceptable specificity to detect executive impairments in BD and ADHD patients. The IFS discriminated between controls and each patient group more reliably than other executive functions measures. Our results suggest that this tool could be a useful instrument to assess executive functions in BD and ADHD patients.

  2. Rituximab is an efficient and safe treatment in adults with steroid-dependent minimal change disease.

    PubMed

    Munyentwali, Helene; Bouachi, Khedidja; Audard, Vincent; Remy, Philippe; Lang, Philippe; Mojaat, Rachid; Deschênes, Georges; Ronco, Pierre M; Plaisier, Emmanuelle M; Dahan, Karine Y

    2013-03-01

    Development of steroid dependency in patients with nephrotic syndrome may require a long-term multi-drug therapy at risk of drug toxicity and renal failure. Rituximab treatment reduces the steroid dosage and the need for immunosuppressive therapy in pediatric patients. Here we retrospectively analyze the efficacy and safety of rituximab in adult patients with steroid-dependent minimal change disease. To do this, we analyzed the outcome of all adult patients treated with rituximab for steroid-dependent minimal change nephrotic syndrome over a mean follow-up of 29.5 months (range 5.1-82 months). Seventeen patients with steroid-dependent or frequently relapsing minimal change nephrotic syndrome, unresponsive to several immunosuppressive medications, were treated with rituximab. Eleven patients had no relapses after rituximab infusion (mean follow-up 26.7 months, range 5.1-82 months) and nine of them were able to come off all other immunosuppressive drugs and steroids during follow-up. Six patients relapsed at least once after a mean time of 11.9 months (mean follow-up 34.5 months, range 16.9-50.1 months), but their immunosuppressive drug treatment could be stopped or markedly reduced during this time. No adverse events were recorded. Thus, rituximab is efficient and safe in adult patients suffering from severe steroid-dependent minimal change disease. Prospective randomized trials are needed to confirm this study.

  3. High-efficiency immunomagnetic isolation of solid tissue-originated integrin-expressing adult stem cells.

    PubMed

    Palmon, Aaron; David, Ran; Neumann, Yoav; Stiubea-Cohen, Raluca; Krief, Guy; Aframian, Doron J

    2012-02-01

    Isolation of highly pure specific cell types is crucial for successful adult stem cell-based therapy. As the number of such cells in adult tissue is low, an extremely efficient method is needed for their isolation. Here, we describe cell-separation methodologies based on magnetic-affinity cell sorting (MACS) MicroBeads with monoclonal antibodies against specific membrane proteins conjugated to superparamagnetic particles. Cells labeled with MACS MicroBeads are retained in a magnetic field within a MACS column placed in a MACS separator, allowing fast and efficient separation. Both positively labeled and non-labeled fractions can be used directly for downstream applications as the separated cell fractions remain viable with no functional impairment. As immunomagnetic separation depends on the interaction between a cell's membrane and the magnetically labeled antibody, separation of specific cells originating from solid tissues is more complex and demands a cell-dissociating pretreatment. In this paper, we detail the use of immunomagnetic separation for the purpose of regenerating damaged salivary gland (SG) function in animal and human models of irradiated head and neck cancer. Each year 500,000 new cases of head and neck cancer occur worldwide. Most of these patients lose SG function following irradiation therapy. SGs contain integrin α6β1-expressing epithelial stem cells. We hypothesized that these cells can be isolated, multiplied in culture and auto-implanted into the irradiated SGs to regenerate damaged SG function.

  4. Human amniotic epithelial cells are reprogrammed more efficiently by induced pluripotency than adult fibroblasts.

    PubMed

    Easley, Charles A; Miki, Toshio; Castro, Carlos A; Ozolek, John A; Minervini, Crescenzio F; Ben-Yehudah, Ahmi; Schatten, Gerald P

    2012-06-01

    Cellular reprogramming from adult somatic cells into an embryonic cell-like state, termed induced pluripotency, has been achieved in several cell types. However, the ability to reprogram human amniotic epithelial cells (hAECs), an abundant cell source derived from discarded placental tissue, has only recently been investigated. Here we show that not only are hAECs easily reprogrammed into induced pluripotent stem cells (AE-iPSCs), but hAECs reprogram faster and more efficiently than adult and neonatal somatic dermal fibroblasts. Furthermore, AE-iPSCs express higher levels of NANOG and OCT4 compared to human foreskin fibroblast iPSCs (HFF1-iPSCs) and express decreased levels of genes associated with differentiation, including NEUROD1 and SOX17, markers of neuronal differentiation. To elucidate the mechanism behind the higher reprogramming efficiency of hAECs, we analyzed global DNA methylation, global histone acetylation, and the mitochondrial DNA A3243G point mutation. Whereas hAECs show no differences in global histone acetylation or mitochondrial point mutation accumulation compared to adult and neonatal dermal fibroblasts, hAECs demonstrate a decreased global DNA methylation compared to dermal fibroblasts. Likewise, quantitative gene expression analyses show that hAECs endogenously express OCT4, SOX2, KLF4, and c-MYC, all four factors used in cellular reprogramming. Thus, hAECs represent an ideal cell type for testing novel approaches for generating clinically viable iPSCs and offer significant advantages over postnatal cells that more likely may be contaminated by environmental exposures and infectious agents. PMID:22686477

  5. A hybrid approach for efficient anomaly detection using metaheuristic methods

    PubMed Central

    Ghanem, Tamer F.; Elkilani, Wail S.; Abdul-kader, Hatem M.

    2014-01-01

    Network intrusion detection based on anomaly detection techniques has a significant role in protecting networks and systems against harmful activities. Different metaheuristic techniques have been used for anomaly detector generation. Yet, reported literature has not studied the use of the multi-start metaheuristic method for detector generation. This paper proposes a hybrid approach for anomaly detection in large scale datasets using detectors generated based on multi-start metaheuristic method and genetic algorithms. The proposed approach has taken some inspiration of negative selection-based detector generation. The evaluation of this approach is performed using NSL-KDD dataset which is a modified version of the widely used KDD CUP 99 dataset. The results show its effectiveness in generating a suitable number of detectors with an accuracy of 96.1% compared to other competitors of machine learning algorithms. PMID:26199752

  6. A hybrid approach for efficient anomaly detection using metaheuristic methods.

    PubMed

    Ghanem, Tamer F; Elkilani, Wail S; Abdul-Kader, Hatem M

    2015-07-01

    Network intrusion detection based on anomaly detection techniques has a significant role in protecting networks and systems against harmful activities. Different metaheuristic techniques have been used for anomaly detector generation. Yet, reported literature has not studied the use of the multi-start metaheuristic method for detector generation. This paper proposes a hybrid approach for anomaly detection in large scale datasets using detectors generated based on multi-start metaheuristic method and genetic algorithms. The proposed approach has taken some inspiration of negative selection-based detector generation. The evaluation of this approach is performed using NSL-KDD dataset which is a modified version of the widely used KDD CUP 99 dataset. The results show its effectiveness in generating a suitable number of detectors with an accuracy of 96.1% compared to other competitors of machine learning algorithms. PMID:26199752

  7. Efficient detection of internal infestation in wheat based on biophotonics.

    PubMed

    Shi, Weiya; Jiao, Keke; Liang, Yitao; Wang, Feng

    2016-02-01

    In the process of grain storage, there are many losses of grain quantity and quality for the sake of insects. As a result, it is necessary to find a rapid and economical method for detecting insects in the grain. The paper innovatively proposes a model of detecting internal infestation in wheat by combining pattern recognition and BioPhoton Analytical Technology (BPAT). In this model, the spontaneous ultraweak photons emitted from normal and insect-contaminated wheat are firstly measured respectively. Then, position, distribution and morphological characteristics can be extracted from the measuring data to construct wheat feature vector. Backpropagation (BP) neural network based on genetic algorithm is employed to take decision on whether wheat kernel has contaminated by insects. The experimental results show that the proposed model can differentiate the normal wheat from the insect-contaminated one at an average accuracy of 95%. The model can also offer a novel thought for detecting internal infestation in the wheat.

  8. A computationally efficient QRS detection algorithm for wearable ECG sensors.

    PubMed

    Wang, Y; Deepu, C J; Lian, Y

    2011-01-01

    In this paper we present a novel Dual-Slope QRS detection algorithm with low computational complexity, suitable for wearable ECG devices. The Dual-Slope algorithm calculates the slopes on both sides of a peak in the ECG signal; And based on these slopes, three criterions are developed for simultaneously checking 1)Steepness 2)Shape and 3)Height of the signal, to locate the QRS complex. The algorithm, evaluated against MIT/BIH Arrhythmia Database, achieves a very high detection rate of 99.45%, a sensitivity of 99.82% and a positive prediction of 99.63%. PMID:22255619

  9. Efficient Lane Boundary Detection with Spatial-Temporal Knowledge Filtering.

    PubMed

    Nan, Zhixiong; Wei, Ping; Xu, Linhai; Zheng, Nanning

    2016-01-01

    Lane boundary detection technology has progressed rapidly over the past few decades. However, many challenges that often lead to lane detection unavailability remain to be solved. In this paper, we propose a spatial-temporal knowledge filtering model to detect lane boundaries in videos. To address the challenges of structure variation, large noise and complex illumination, this model incorporates prior spatial-temporal knowledge with lane appearance features to jointly identify lane boundaries. The model first extracts line segments in video frames. Two novel filters-the Crossing Point Filter (CPF) and the Structure Triangle Filter (STF)-are proposed to filter out the noisy line segments. The two filters introduce spatial structure constraints and temporal location constraints into lane detection, which represent the spatial-temporal knowledge about lanes. A straight line or curve model determined by a state machine is used to fit the line segments to finally output the lane boundaries. We collected a challenging realistic traffic scene dataset. The experimental results on this dataset and other standard dataset demonstrate the strength of our method. The proposed method has been successfully applied to our autonomous experimental vehicle. PMID:27529248

  10. Efficient Lane Boundary Detection with Spatial-Temporal Knowledge Filtering

    PubMed Central

    Nan, Zhixiong; Wei, Ping; Xu, Linhai; Zheng, Nanning

    2016-01-01

    Lane boundary detection technology has progressed rapidly over the past few decades. However, many challenges that often lead to lane detection unavailability remain to be solved. In this paper, we propose a spatial-temporal knowledge filtering model to detect lane boundaries in videos. To address the challenges of structure variation, large noise and complex illumination, this model incorporates prior spatial-temporal knowledge with lane appearance features to jointly identify lane boundaries. The model first extracts line segments in video frames. Two novel filters—the Crossing Point Filter (CPF) and the Structure Triangle Filter (STF)—are proposed to filter out the noisy line segments. The two filters introduce spatial structure constraints and temporal location constraints into lane detection, which represent the spatial-temporal knowledge about lanes. A straight line or curve model determined by a state machine is used to fit the line segments to finally output the lane boundaries. We collected a challenging realistic traffic scene dataset. The experimental results on this dataset and other standard dataset demonstrate the strength of our method. The proposed method has been successfully applied to our autonomous experimental vehicle. PMID:27529248

  11. Detection of Adult Beetles Inside the Stored Wheat Mass Based on Their Acoustic Emissions.

    PubMed

    Eliopoulos, P A; Potamitis, I; Kontodimas, D Ch; Givropoulou, E G

    2015-12-01

    The efficacy of bioacoustics in detecting the presence of adult beetles inside the grain mass was evaluated in the laboratory. A piezoelectric sensor and a portable acoustic emission amplifier connected with a computer were used. Adults of the most common beetle pests of stored wheat have been detected in varying population densities (0.1, 0.5, 1, and 2 adults per kilogram of wheat). The verification of the presence of the insect individuals was achieved through automated signal parameterization and classification. We tried out two different ways to detect impulses: 1) by applying a Hilbert transform on the audio recording and 2) by subtracting a noise estimation of the recording from the spectral content of the recording, thus allowing the frequency content of possible impulses to emerge. Prediction for infestation was rated falsely negative in 60-74%, 48-60%, 0-28%, and 0-4% of the cases when actual population density was 0.1, 0.5, 1, and 2 adults per kilogram, respectively, irrespective of pest species. No significant differences were recorded in positive predictions among different species in almost all cases. The system was very accurate (72-100%) in detecting 1 or 2 insects per kilogram of hard wheat grain, which is the standard threshold for classifying a grain mass "clean" or "infested." Our findings are discussed on the basis of enhancing the use of bioacoustics in stored-product IPM framework.

  12. Olfactory Detection Thresholds and Adaptation in Adults with Autism Spectrum Condition

    ERIC Educational Resources Information Center

    Tavassoli, T.; Baron-Cohen, S.

    2012-01-01

    Sensory issues have been widely reported in Autism Spectrum Conditions (ASC). Since olfaction is one of the least investigated senses in ASC, the current studies explore olfactory detection thresholds and adaptation to olfactory stimuli in adults with ASC. 80 participants took part, 38 (18 females, 20 males) with ASC and 42 control participants…

  13. A Curriculum Structured Design for Educating Adults in Detecting Deception and Eliciting Information

    ERIC Educational Resources Information Center

    McManus, Barry L.

    2013-01-01

    This dissertation describes the overall effectiveness of deception detection training and identifies conditions that may enhance training effectiveness through understanding how adults learn and utilizing scenario-based training. The analysis was based on a total of 1,788 evaluation data sheets (archival records). The major aim of the research is…

  14. Plagiarism by Adult Learners Online: A Case Study in Detection and Remediation

    ERIC Educational Resources Information Center

    Jocoy, Christine; DiBiase, David

    2006-01-01

    Detecting and combating plagiarism from Web-based sources is a concern for administrators and instructors involved in online distance education. In this paper, we quantify copy-and-paste plagiarism among adult learners in an online geography course offered through Penn State's World Campus Geographic Information Systems (GIS) certificate program.…

  15. An efficient background modeling approach based on vehicle detection

    NASA Astrophysics Data System (ADS)

    Wang, Jia-yan; Song, Li-mei; Xi, Jiang-tao; Guo, Qing-hua

    2015-10-01

    The existing Gaussian Mixture Model(GMM) which is widely used in vehicle detection suffers inefficiency in detecting foreground image during the model phase, because it needs quite a long time to blend the shadows in the background. In order to overcome this problem, an improved method is proposed in this paper. First of all, each frame is divided into several areas(A, B, C and D), Where area A, B, C and D are decided by the frequency and the scale of the vehicle access. For each area, different new learning rate including weight, mean and variance is applied to accelerate the elimination of shadows. At the same time, the measure of adaptive change for Gaussian distribution is taken to decrease the total number of distributions and save memory space effectively. With this method, different threshold value and different number of Gaussian distribution are adopted for different areas. The results show that the speed of learning and the accuracy of the model using our proposed algorithm surpass the traditional GMM. Probably to the 50th frame, interference with the vehicle has been eliminated basically, and the model number only 35% to 43% of the standard, the processing speed for every frame approximately has a 20% increase than the standard. The proposed algorithm has good performance in terms of elimination of shadow and processing speed for vehicle detection, it can promote the development of intelligent transportation, which is very meaningful to the other Background modeling methods.

  16. Fearful face detection sensitivity in healthy adults correlates with anxiety-related traits.

    PubMed

    Doty, Tracy J; Japee, Shruti; Ingvar, Martin; Ungerleider, Leslie G

    2013-04-01

    Threatening faces have a privileged status in the brain, which can be reflected in a processing advantage. However, this effect varies among individuals, even healthy adults. For example, one recent study showed that fearful face detection sensitivity correlated with trait anxiety in healthy adults (S. Japee, L. Crocker, F. Carver, L. Pessoa, & L. G. Ungerleider, 2009. Individual differences in valence modulation of face-selective M170 response. Emotion, 9, 59-69). Here, we expanded on those findings by investigating whether intersubject variability in fearful face detection is also associated with state anxiety, as well as more broadly with other traits related to anxiety. To measure fearful face detection sensitivity, we used a masked face paradigm where the target face was presented for only 33 ms and was immediately followed by a neutral face mask. Subjects then rated their confidence in detecting either fear or no fear in the target face. Fearful face detection sensitivity was calculated for each subject using signal detection theory. Replicating previous results, we found a significant positive correlation between trait anxiety and fearful face detection sensitivity. However, this behavioral advantage did not correlate with state anxiety. We also found that fearful face detection sensitivity correlated with other personality measures, including neuroticism and harm avoidance. Our data suggest that fearful face detection sensitivity varies parametrically across the healthy population, is associated broadly with personality traits related to anxiety, but remains largely unaffected by situational fluctuations in anxiety. These results underscore the important contribution of anxiety-related personality traits to threat processing in healthy adults.

  17. Study of Total Detection Efficiency (η) of Charge Exchange Analyzer (CXA) in TVD Tokamak

    NASA Astrophysics Data System (ADS)

    Kazemi, M.; Habibi, M.; Tafreshi, M.

    2013-02-01

    Diagnostic devices detection efficiency consist of many parameters. Contribution of each part in main detection efficiency need to study all aspect of devices and experimentally researches. In this paper experimental results and theoretical study merged to figure out the total detection efficiency of CXA. Most important primary parameters has been recognized (stripping foil thickness, incident energy, etc.) and effect of these parameters in related part studied. For CXA of TVD tokamak total detection efficiency presented and shown for 3 keV this parameter equal to .09 and stripping efficiency is equal 1.1 approximately. Choosing appropriate system for stripping of neutral beam is the most important factor in CXA diagnostic devices specially for high energy beams.

  18. The need for improved detection and management of adult-onset hearing loss in australia.

    PubMed

    McMahon, Catherine M; Gopinath, Bamini; Schneider, Julie; Reath, Jennifer; Hickson, Louise; Leeder, Stephen R; Mitchell, Paul; Cowan, Robert

    2013-01-01

    Adult-onset hearing loss is insidious and typically diagnosed and managed several years after onset. Often, this is after the loss having led to multiple negative consequences including effects on employment, depressive symptoms, and increased risk of mortality. In contrast, the use of hearing aids is associated with reduced depression, longer life expectancy, and retention in the workplace. Despite this, several studies indicate high levels of unmet need for hearing health services in older adults and poor use of prescribed hearing aids, often leading to their abandonment. In Australia, the largest component of financial cost of hearing loss (excluding the loss of well-being) is due to lost workplace productivity. Nonetheless, the Australian public health system does not have an effective and sustainable hearing screening strategy to tackle the problem of poor detection of adult-onset hearing loss. Given the increasing prevalence and disease burden of hearing impairment in adults, two key areas are not adequately met in the Australian healthcare system: (1) early identification of persons with chronic hearing impairment; (2) appropriate and targeted referral of these patients to hearing health service providers. This paper reviews the current literature, including population-based data from the Blue Mountains Hearing Study, and suggests different models for early detection of adult-onset hearing loss. PMID:23710184

  19. Generalized Linear Models of home activity for automatic detection of mild cognitive impairment in older adults.

    PubMed

    Akl, Ahmad; Snoek, Jasper; Mihailidis, Alex

    2014-01-01

    With a globally aging population, the burden of care of cognitively impaired older adults is becoming increasingly concerning. Instances of Alzheimer's disease and other forms of dementia are becoming ever more frequent. Earlier detection of cognitive impairment offers significant benefits, but remains difficult to do in practice. In this paper, we develop statistical models of the behavior of older adults within their homes using sensor data in order to detect the early onset of cognitive decline. Specifically, we use inhomogenous Poisson processes to model the presence of subjects within different rooms throughout the day in the home using unobtrusive sensing technologies. We compare the distributions learned from cognitively intact and impaired subjects using information theoretic tools and observe statistical differences between the two populations which we believe can be used to help detect the onset of cognitive decline.

  20. Generalized Linear Models of home activity for automatic detection of mild cognitive impairment in older adults.

    PubMed

    Akl, Ahmad; Snoek, Jasper; Mihailidis, Alex

    2014-01-01

    With a globally aging population, the burden of care of cognitively impaired older adults is becoming increasingly concerning. Instances of Alzheimer's disease and other forms of dementia are becoming ever more frequent. Earlier detection of cognitive impairment offers significant benefits, but remains difficult to do in practice. In this paper, we develop statistical models of the behavior of older adults within their homes using sensor data in order to detect the early onset of cognitive decline. Specifically, we use inhomogenous Poisson processes to model the presence of subjects within different rooms throughout the day in the home using unobtrusive sensing technologies. We compare the distributions learned from cognitively intact and impaired subjects using information theoretic tools and observe statistical differences between the two populations which we believe can be used to help detect the onset of cognitive decline. PMID:25570050

  1. And along Came a Spider: An Attentional Bias for the Detection of Spiders in Young Children and Adults

    ERIC Educational Resources Information Center

    LoBue, Vanessa

    2010-01-01

    Spiders are among the most common targets of fears and phobias in the world. In visual search tasks, adults detect their presence more rapidly than other kinds of stimuli. Reported here is an investigation of whether young children share this attentional bias for the detection of spiders. In a series of experiments, preschoolers and adults were…

  2. [Background factors in the detection of drug-resistant bacteria in adult patients with acute rhinosinusitis].

    PubMed

    Tomiyama, Michio

    2014-02-01

    In the treatment of adult patients with acute rhinosinusitis, it has been assumed that subjects over 65 years of age or living with children attending a day nursery, are at higher risk for infection with drug-resistant bacteria. However there are few reports which have discussed the relationship between those risk factors and adult patients with acute rhinosinusitis. I investigated the association between adult patients with acute rhinosinusitis living with children attending a day nursery and gender, ages, and frequency of detection of drug-resistant bacteria. From 2010 to 2012, a total of 598 adult patients with acute rhinosinusitis were enrolled. The majority of the study subjects were women, and the largest 10-year age group was 30-39 years. By sex, a greater proportion of the female subjects than the male subjects lived with children attending a day nursery. By age, the proportion of subjects who lived with children attending a day nursery was significantly higher in the 30-39-year age group than other age groups. Drug-resistant Streptococcus pneumoniae and ampicillin (ABPC)-resistant Haemophilus influenzae were detected at significantly higher rates in subjects with children attending a day nursery than in those without. There were no significant difference in drug-resistant bacteria detection between subjects over 65 years of age, and under 65 years. These findings suggested that living with children attending a day nursery is a risk factor and source of infection by drug-resistant organisms that may cause intra-familial infections of adult patients with acute rhinosinusitis. These results suggested we must ask adult patients with acute rhinosinusitis whether they are living with children attending a day nursery or not, when we plan their treatment strategy.

  3. Preparation and characterization of specific monoclonal antibodies for the detection of adult worm infections in onchocerciasis.

    PubMed

    Cho-Ngwa, Fidelis; Daggfeldt, Annika; Titanji, Vincent P K; Grönvik, Kjell-Olov

    2005-12-01

    Suitable molecular tests for monitoring the viability of adult worms of Onchocerca in vivo are required to accelerate the development of new macrofilaricides in river blindness (onchocerciasis). Hence, three monoclonal antibodies (MAbs) were prepared and evaluated in a sandwich enzyme-linked immunosorbent assay (ELISA) for their abilities to detect circulating adult worm antigens in onchocercal bovine and human sera. The MAbs did not cross-react with a number of control antigens, which included extracts of Ascaris suum, Loa loa, and O. ochengi microfilariae. They were all IgG1 molecules. Their targets in O. ochengi total extract were a set of the same 15 polypeptides with apparent molecular weights of 21-220 Kda. Immunohistochemical studies confirmed their adult worm specificity and showed their binding to the hypodermis of the adult worm. The ELISA could detect as little as 100 pg/mL of the affinity-purified target antigens. It also detected the antigens with 94.1% specificity in 50 out of 56 infected bovine sera (90% sensitivity) and in 21 out of 43 infected human sera (48.8% sensitivity, which could go up to 72.1% on elimination of two skewed control cases). We conclude that the MAbs could be field tested and used in responder populations as described herein or employed as components of more sensitive assays for the evaluation of novel Onchocerca macrofilaricides.

  4. An Efficient Method for Detecting Misbehaving Zone Manager in MANET

    NASA Astrophysics Data System (ADS)

    Rafsanjani, Marjan Kuchaki; Pakzad, Farzaneh; Asadinia, Sanaz

    In recent years, one of the wireless technologies increased tremendously is mobile ad hoc networks (MANETs) in which mobile nodes organize themselves without the help of any predefined infrastructure. MANETs are highly vulnerable to attack due to the open medium, dynamically changing network topology, cooperative algorithms, lack of centralized monitoring, management point and lack of a clear defense line. In this paper, we report our progress in developing intrusion detection (ID) capabilities for MANET. In our proposed scheme, the network with distributed hierarchical architecture is partitioned into zones, so that in each of them there is one zone manager. The zone manager is responsible for monitoring the cluster heads in its zone and cluster heads are in charge of monitoring their members. However, the most important problem is how the trustworthiness of the zone manager can be recognized. So, we propose a scheme in which "honest neighbors" of zone manager specify the validation of their zone manager. These honest neighbors prevent false accusations and also allow manager if it is wrongly misbehaving. However, if the manger repeats its misbehavior, then it will lose its management degree. Therefore, our scheme will be improved intrusion detection and also provide a more reliable network.

  5. Efficient detection and recognition algorithm of reference points in photogrammetry

    NASA Astrophysics Data System (ADS)

    Li, Weimin; Liu, Gang; Zhu, Lichun; Li, Xiaofeng; Zhang, Yuhai; Shan, Siyu

    2016-04-01

    In photogrammetry, an approach of automatic detection and recognition on reference points have been proposed to meet the requirements on detection and matching of reference points. The reference points used here are the CCT(circular coded target), which compose of two parts: the round target point in central region and the circular encoding band in surrounding region. Firstly, the contours of image are extracted, after that noises and disturbances of the image are filtered out by means of a series of criteria, such as the area of the contours, the correlation coefficient between two regions of contours etc. Secondly, the cubic spline interpolation is adopted to process the central contour region of the CCT. The contours of the interpolated image are extracted again, then the least square ellipse fitting is performed to calculate the center coordinates of the CCT. Finally, the encoded value is obtained by the angle information from the circular encoding band of the CCT. From the experiment results, the location precision of the CCT can be achieved to sub-pixel level of the algorithm presented. Meanwhile the recognition accuracy is pretty high, even if the background of the image is complex and full of disturbances. In addition, the property of the algorithm is robust. Furthermore, the runtime of the algorithm is fast.

  6. Thermal and health outcomes of energy efficiency retrofits of homes of older adults.

    PubMed

    Ahrentzen, S; Erickson, J; Fonseca, E

    2016-08-01

    Mitigation of thermal stress and adverse indoor climatic conditions is important to older low-income populations whose age, health, and economic circumstances make them vulnerable to indoor environmental conditions. This research examines whether energy retrofits in affordable housing for older adults can also improve indoor climatic (i.e., temperature, humidity, air infiltration) conditions and whether such improvements correspond with improved health and comfort of residents. An apartment complex for low-income older adults in Phoenix was the study site. In 2010, renovations were undertaken to make it more energy efficient and to replace interior cabinetry, flooring, and paint with materials that had low or no volatile organic compounds (VOCs). Fifty-seven residents from 53 apartment units participated in both baseline (pre-renovation) and 1 year post-renovation data collection trials. Environmental measures included temperature, relative humidity, and air infiltration. Health measures included general health, emotional distress, and sleep. Four questions addressed residents' perceptions of temperature quality. Results demonstrated a 19% reduction in energy consumption following the retrofit. In addition, fixed effects statistical models of the panel data showed significant stabilization of unit temperature from pre-retrofit to 1 year post-retrofit. Reductions in an apartment's temperature extremes of 27.2°C (81°F) and above also corresponded with improvement in occupant's reported health over the same time period, although not with occupant's perceptions of thermal comfort.

  7. Efficiency and Accuracy of Bernese Periacetabular Osteotomy for Adult Hip Dysplasia

    PubMed Central

    Luo, Dian‐zhong; Xiao, Kai; Cheng, Hui

    2015-01-01

    Bernese periacetabular osteotomy (PAO) has several advantages dealing with adolescents and adults acetabular dysplasia. The authors introduced the details and steps performing PAO, with attached video and schematic diagram which demonstrates a perfect PAO in efficiency and accuracy. The patient is an 18‐year‐old girl, complaining hip pain on the left side for 6 months. Physical examination shows normal gait and range of motion (ROM) of the left hip. Pelvic anteroposterior X‐ray shows acetabular dysplasia on the left, and post operation on the right. She is very satisfied with the PAO on the right one year before, so we recommend PAO for the left hip dysplasia again. The key point of PAO includes 4 cuts: ischial cut, pubic cut, acetabular roof cut, and quadrilateral bone cut, and the four cuts should be accomplished accurately. Then the acetabular fragment should be turned to ideal position with the lateral CE angle (LCE) > 25°, the Tönnis acetabular angle 0°, the anterior CE angle (ACE) > 20°, good congruence joint space, and with the hip center medialized slightly. At lastly the acetabular fragment is fixed with proper nails and instruments. The patient is very happy to the surgery with no hip pain, with normal gait, ROM, and Harris hip scores (HHS). In summary, PAO is a relative new and efficient procedure for adult hip dysplasia, requiring accurate techniques. Cadaveric practice and familiar with the local anatomy can help the surgeon overcome the learning curve quickly. PMID:26791326

  8. An efficient method for facial component detection in thermal images

    NASA Astrophysics Data System (ADS)

    Paul, Michael; Blanik, Nikolai; Blazek, Vladimir; Leonhardt, Steffen

    2015-04-01

    A method to detect certain regions in thermal images of human faces is presented. In this approach, the following steps are necessary to locate the periorbital and the nose regions: First, the face is segmented from the background by thresholding and morphological filtering. Subsequently, a search region within the face, around its center of mass, is evaluated. Automatically computed temperature thresholds are used per subject and image or image sequence to generate binary images, in which the periorbital regions are located by integral projections. Then, the located positions are used to approximate the nose position. It is possible to track features in the located regions. Therefore, these regions are interesting for different applications like human-machine interaction, biometrics and biomedical imaging. The method is easy to implement and does not rely on any training images or templates. Furthermore, the approach saves processing resources due to simple computations and restricted search regions.

  9. Efficient hemodynamic event detection utilizing relational databases and wavelet analysis

    NASA Technical Reports Server (NTRS)

    Saeed, M.; Mark, R. G.

    2001-01-01

    Development of a temporal query framework for time-oriented medical databases has hitherto been a challenging problem. We describe a novel method for the detection of hemodynamic events in multiparameter trends utilizing wavelet coefficients in a MySQL relational database. Storage of the wavelet coefficients allowed for a compact representation of the trends, and provided robust descriptors for the dynamics of the parameter time series. A data model was developed to allow for simplified queries along several dimensions and time scales. Of particular importance, the data model and wavelet framework allowed for queries to be processed with minimal table-join operations. A web-based search engine was developed to allow for user-defined queries. Typical queries required between 0.01 and 0.02 seconds, with at least two orders of magnitude improvement in speed over conventional queries. This powerful and innovative structure will facilitate research on large-scale time-oriented medical databases.

  10. Efficient Enzyme-Free Biomimetic Sensors for Natural Phenol Detection.

    PubMed

    Ferreira Garcia, Luane; Ribeiro Souza, Aparecido; Sanz Lobón, Germán; Dos Santos, Wallans Torres Pio; Alecrim, Morgana Fernandes; Fontes Santiago, Mariângela; de Sotomayor, Rafael Luque Álvarez; de Souza Gil, Eric

    2016-01-01

    The development of sensors and biosensors based on copper enzymes and/or copper oxides for phenol sensing is disclosed in this work. The electrochemical properties were studied by cyclic and differential pulse voltammetry using standard solutions of potassium ferrocyanide, phosphate/acetate buffers and representative natural phenols in a wide pH range (3.0 to 9.0). Among the natural phenols herein investigated, the highest sensitivity was observed for rutin, a powerful antioxidant widespread in functional foods and ubiquitous in the plant kingdom. The calibration curve for rutin performed at optimum pH (7.0) was linear in a broad concentration range, 1 to 120 µM (r = 0.99), showing detection limits of 0.4 µM. The optimized biomimetic sensor was also applied in total phenol determination in natural samples, exhibiting higher stability and sensitivity as well as distinct selectivity for antioxidant compounds. PMID:27529208

  11. Note: Determining the detection efficiency of excited neutral atoms by a microchannel plate detector

    SciTech Connect

    Berry, Ben; Zohrabi, M.; Hayes, D.; Ablikim, U.; Jochim, Bethany; Severt, T.; Carnes, K. D.; Ben-Itzhak, I.

    2015-04-15

    We present a method for determining the detection efficiency of neutral atoms relative to keV ions. Excited D* atoms are produced by D{sub 2} fragmentation in a strong laser field. The fragments are detected by a micro-channel plate detector either directly as neutrals or as keV ions following field ionization and acceleration by a static electric field. Moreover, we propose a new mechanism by which neutrals are detected. We show that the ratio of the yield of neutrals and ions can be related to the relative detection efficiency of these species.

  12. High-efficiency interferometer for noncontact detection of ultrasounds

    NASA Astrophysics Data System (ADS)

    Czarnek, Robert; Yu, Chin-Jye; Dax, F. R.

    1995-06-01

    Semi-solid metalworking (SSM) incorporates elements of both casting and forging for the manufacture of near-net shape discrete parts. The SSM process capitalizes on thixotropy, a physical state wherein a partially molten material behaves like a fluid when a shear stress is applied. Effective process control depends on the accurate measurement of the ratio between solid and liquid in the feedstock. Due to the high temperature of the material, only noncontact measurements are practical. Surface temperature measurements are not reliable and do not give accurate readings of the bulk material temperature. Since the speed of sound changes during the transition from the solid to the liquid state, ultrasonics offers the potential to determine when a material becomes semi-solid. This paper summarizes attempts to use this change as the means of measuring the solid fraction of semi-solid feedstock. A real time solid fraction sensor system using noncontact laser ultrasonics was developed to measure the SSM material's solid fraction during heating. The system includes a high power Nd:Yag laser for ultrasound generation and a Fabry-Perot interferometer for receiving. The interferometer was optimized for maximum light efficiency and for immunity to the electro-magnetic noise generated by the induction furnaces used in heating the SSM billets. Tests have demonstrated excellent signal to noise ratio at room temperature and at temperatures up to 579 degrees C. A summary of the test results is presented.

  13. Efficient Detection of Occlusion prior to Robust Face Recognition

    PubMed Central

    Dugelay, Jean-Luc

    2014-01-01

    While there has been an enormous amount of research on face recognition under pose/illumination/expression changes and image degradations, problems caused by occlusions attracted relatively less attention. Facial occlusions, due, for example, to sunglasses, hat/cap, scarf, and beard, can significantly deteriorate performances of face recognition systems in uncontrolled environments such as video surveillance. The goal of this paper is to explore face recognition in the presence of partial occlusions, with emphasis on real-world scenarios (e.g., sunglasses and scarf). In this paper, we propose an efficient approach which consists of first analysing the presence of potential occlusion on a face and then conducting face recognition on the nonoccluded facial regions based on selective local Gabor binary patterns. Experiments demonstrate that the proposed method outperforms the state-of-the-art works including KLD-LGBPHS, S-LNMF, OA-LBP, and RSC. Furthermore, performances of the proposed approach are evaluated under illumination and extreme facial expression changes provide also significant results. PMID:24526902

  14. Efficient detection of occlusion prior to robust face recognition.

    PubMed

    Min, Rui; Hadid, Abdenour; Dugelay, Jean-Luc

    2014-01-01

    While there has been an enormous amount of research on face recognition under pose/illumination/expression changes and image degradations, problems caused by occlusions attracted relatively less attention. Facial occlusions, due, for example, to sunglasses, hat/cap, scarf, and beard, can significantly deteriorate performances of face recognition systems in uncontrolled environments such as video surveillance. The goal of this paper is to explore face recognition in the presence of partial occlusions, with emphasis on real-world scenarios (e.g., sunglasses and scarf). In this paper, we propose an efficient approach which consists of first analysing the presence of potential occlusion on a face and then conducting face recognition on the nonoccluded facial regions based on selective local Gabor binary patterns. Experiments demonstrate that the proposed method outperforms the state-of-the-art works including KLD-LGBPHS, S-LNMF, OA-LBP, and RSC. Furthermore, performances of the proposed approach are evaluated under illumination and extreme facial expression changes provide also significant results.

  15. Theoretical determination of the neuron detection efficiency of plastic track detectors. I. Theoretical model

    NASA Astrophysics Data System (ADS)

    Pretzsch, Gunter

    A theoretical model to determine the neutron detection efficiency of organic solid state nuclear track detectors without external radiator is described. The model involves the following calculation steps: production of heavy charged particles within the detector volume, characterization of the charged particles by appropriate physical quantities, application of suitable registration criteria, formation of etch pits. The etch pits formed are described by means of a distribution function which is doubly differential in both diameter and depth of the etch pits. The distribution function serves as the input value for the calculation of the detection efficiency. The detection efficiency is defined as the measured effect per neutron fluence. Hence it depends on the evaluation technique considered. The calculation of the distribution function is carried out for cellulose triacetate. The determination of the concrete detection efficiency using the light microscope and light transmission measurements as the evaluation technique will be described in further publications.

  16. Detection-efficiency loophole and the Pusey-Barrett-Rudolph theorem

    NASA Astrophysics Data System (ADS)

    Dutta, Arijit; Pawłowski, Marcin; Żukowski, Marek

    2015-04-01

    The detection-efficiency loophole poses a significant problem for experimental tests of Bell inequalities. The recently discovered Pusey-Barrett-Rudolph (PBR) theorem suffers from the same vulnerability. In this paper we calculate the critical detection efficiency, below which the PBR argument for the ontic nature of quantum state is inconclusive. This is done for the maximally ψ -epistemic models. We use two different definitions of this property. The optimal number of parties for which the critical detection efficiency is the lowest is given. We also approach the problem from the opposite direction. We provide a function that enables us to specify which epistemic models are ruled out by the results of an experiment with a given detection efficiency.

  17. A comparison of digital radiography systems in terms of effective detective quantum efficiency

    SciTech Connect

    Bertolini, Marco; Nitrosi, Andrea; Rivetti, Stefano; Lanconelli, Nico; Pattacini, Pierpaolo; Ginocchi, Vladimiro; Iori, Mauro

    2012-05-15

    Purpose: The purpose of this study is to compare digital radiography systems using the metric effective detective quantum efficiency (eDQE), which better reflects digital radiography imaging system performance under clinical operating conditions, in comparison with conventional metrics such as modulation transfer function (MTF), normalized noise power spectra (NNPS), and detective quantum efficiency (DQE). Methods: The eDQE was computed by the calculation of the MTF, the NNPS, the phantom attenuation and scatter, and estimation of x-ray flux. The physical characterization of the systems was obtained with the standard beam conditions RQA5 and RQA9, using the PA Chest phantom proposed by AAPM Report no. 31 simulating the attenuation and scatter characteristics of the adult human thorax. The MTF (eMTF) was measured by using an edge test placed at the frontal surface of the phantom, the NNPS (eNNPS) was calculated from images of the phantom acquired at three different exposure levels covering the operating range of the system (E{sub 0}, which is the exposure at which a system is normally operated, 1/3 E{sub 0}, and 3 E0), and scatter measurements were assessed by using a beam-stop technique. The integral of DQE (IDQE) and eDQE (IeDQE) was calculated over the whole spatial frequency range. Results: The eMTF results demonstrate degradation due to magnification and the presence of scattered radiation. The eNNPS was influenced by the grid presence, and in some systems, it contained structured noise. At typical clinical exposure levels, the magnitude of eDQE(0) with respect to DQE(0) at RQA9 beam conditions was 13%, 17%, 16%, 36%, and 24%, respectively, for Carestream DRX-1, Carestream DRX-1C, Carestream Direct View CR975, Philips Digital Diagnost VM, and GE Revolution XR/d. These results were confirmed by the ratio of IeDQE and IDQE in the same conditions. Conclusions: The authors confirm the robustness and reproducibility of the eDQE method. As expected, the DR systems

  18. Empirical technique to measure x-ray production and detection efficiencies in the analytical electron microscope

    SciTech Connect

    King, W.E.

    1985-01-01

    In the present work, a technique is proposed to experimentally measure the effective x-ray production and detection efficiency in pure element standards. This technique supplements and in some cases is preferable to the multi-element standard technique. Measurements of effective x-ray production and detection efficiencies are expected to be preferable to the standardless technique in cases where pure element samples can be prepared since the most uncertain parameters in the standardless technique are measured in the proposed technique.

  19. Electrophysiological evidence of atypical visual change detection in adults with autism.

    PubMed

    Cléry, H; Roux, S; Houy-Durand, E; Bonnet-Brilhault, F; Bruneau, N; Gomot, M

    2013-01-01

    Although atypical change detection processes have been highlighted in the auditory modality in autism spectrum disorder (ASD), little is known about these processes in the visual modality. The aim of the present study was therefore to investigate visual change detection in adults with ASD, taking into account the salience of change, in order to determine whether this ability is affected in this disorder. Thirteen adults with ASD and 13 controls were presented with a passive visual three stimuli oddball paradigm. The findings revealed atypical visual change processing in ASD. Whereas controls displayed a vMMN in response to deviant and a novelty P3 in response to novel stimuli, patients with ASD displayed a novelty P3 in response to both deviant and novel stimuli. These results thus suggested atypical orientation of attention toward unattended minor changes in ASD that might contribute to the intolerance of change.

  20. fMRI investigation of visual change detection in adults with autism.

    PubMed

    Clery, H; Andersson, F; Bonnet-Brilhault, F; Philippe, A; Wicker, B; Gomot, M

    2013-01-01

    People with autism spectrum disorders (ASD) may show unusual reactions to unexpected changes that appear in their environment. Although several studies have highlighted atypical auditory change processing in ASD, little is known in this disorder about the brain processes involved in visual automatic change detection. The present fMRI study was designed to localize brain activity elicited by unexpected visual changing stimuli in adults with ASD compared to controls. Twelve patients with ASD and 17 healthy adults participated in the experiment in which subjects were presented with a visual oddball sequence while performing a concurrent target detection task. Combined results across participants highlight the involvement of both occipital (BA 18/19) and frontal (BA 6/8) regions during visual change detection. However, adults with ASD display greater activity in the bilateral occipital cortex and in the anterior cingulate cortex (ACC) associated with smaller activation in the superior and middle frontal gyri than controls. A psychophysiological interaction (PPI) analysis was performed with ACC as the seed region and revealed greater functionally connectivity to sensory regions in ASD than in controls, but less connectivity to prefrontal and orbito-frontal cortices. Thus, compared to controls, larger sensory activation associated with reduced frontal activation was seen in ASD during automatic visual change detection. Atypical psychophysiological interactions between frontal and occipital regions were also found, congruent with the idea of atypical connectivity between these regions in ASD. The atypical involvement of the ACC in visual change detection can be related to abnormalities previously observed in the auditory modality, thus supporting the hypothesis of an altered general mechanism of change detection in patients with ASD that would underlie their unusual reaction to change.

  1. fMRI investigation of visual change detection in adults with autism☆

    PubMed Central

    Clery, H.; Andersson, F.; Bonnet-Brilhault, F.; Philippe, A.; Wicker, B.; Gomot, M.

    2013-01-01

    People with autism spectrum disorders (ASD) may show unusual reactions to unexpected changes that appear in their environment. Although several studies have highlighted atypical auditory change processing in ASD, little is known in this disorder about the brain processes involved in visual automatic change detection. The present fMRI study was designed to localize brain activity elicited by unexpected visual changing stimuli in adults with ASD compared to controls. Twelve patients with ASD and 17 healthy adults participated in the experiment in which subjects were presented with a visual oddball sequence while performing a concurrent target detection task. Combined results across participants highlight the involvement of both occipital (BA 18/19) and frontal (BA 6/8) regions during visual change detection. However, adults with ASD display greater activity in the bilateral occipital cortex and in the anterior cingulate cortex (ACC) associated with smaller activation in the superior and middle frontal gyri than controls. A psychophysiological interaction (PPI) analysis was performed with ACC as the seed region and revealed greater functionally connectivity to sensory regions in ASD than in controls, but less connectivity to prefrontal and orbito-frontal cortices. Thus, compared to controls, larger sensory activation associated with reduced frontal activation was seen in ASD during automatic visual change detection. Atypical psychophysiological interactions between frontal and occipital regions were also found, congruent with the idea of atypical connectivity between these regions in ASD. The atypical involvement of the ACC in visual change detection can be related to abnormalities previously observed in the auditory modality, thus supporting the hypothesis of an altered general mechanism of change detection in patients with ASD that would underlie their unusual reaction to change. PMID:24179785

  2. Clustering Home Activity Distributions for Automatic Detection of Mild Cognitive Impairment in Older Adults1

    PubMed Central

    Akl, Ahmad; Chikhaoui, Belkacem; Mattek, Nora; Kaye, Jeffrey; Austin, Daniel; Mihailidis, Alex

    2016-01-01

    The public health implications of growing numbers of older adults at risk for dementia places pressure on identifying dementia at its earliest stages so as to develop proactive management plans. The prodromal dementia phase commonly identified as mild cognitive impairment is an important target for this early detection of impending dementia amenable to treatment. In this paper, we propose a method for home-based automatic detection of mild cognitive impairment in older adults through continuous monitoring via unobtrusive sensing technologies. Our method is composed of two main stages: a training stage and a test stage. For training, room activity distributions are estimated for each subject using a time frame of ω weeks, and then affinity propagation is employed to cluster the activity distributions and to extract exemplars to represent the different emerging clusters. For testing, room activity distributions belonging to a test subject with unknown cognitive status are compared to the extracted exemplars and get assigned the labels of the exemplars that result in the smallest normalized Kullbak–Leibler divergence. The labels of the activity distributions are then used to determine the cognitive status of the test subject. Using the sensor and clinical data pertaining to 85 homes with single occupants, we were able to automatically detect mild cognitive impairment in older adults with an F0.5 score of 0.856. Also, we were able to detect the non-amnestic sub-type of mild cognitive impairment in older adults with an F0.5 score of 0.958. PMID:27617044

  3. Clustering Home Activity Distributions for Automatic Detection of Mild Cognitive Impairment in Older Adults1

    PubMed Central

    Akl, Ahmad; Chikhaoui, Belkacem; Mattek, Nora; Kaye, Jeffrey; Austin, Daniel; Mihailidis, Alex

    2016-01-01

    The public health implications of growing numbers of older adults at risk for dementia places pressure on identifying dementia at its earliest stages so as to develop proactive management plans. The prodromal dementia phase commonly identified as mild cognitive impairment is an important target for this early detection of impending dementia amenable to treatment. In this paper, we propose a method for home-based automatic detection of mild cognitive impairment in older adults through continuous monitoring via unobtrusive sensing technologies. Our method is composed of two main stages: a training stage and a test stage. For training, room activity distributions are estimated for each subject using a time frame of ω weeks, and then affinity propagation is employed to cluster the activity distributions and to extract exemplars to represent the different emerging clusters. For testing, room activity distributions belonging to a test subject with unknown cognitive status are compared to the extracted exemplars and get assigned the labels of the exemplars that result in the smallest normalized Kullbak–Leibler divergence. The labels of the activity distributions are then used to determine the cognitive status of the test subject. Using the sensor and clinical data pertaining to 85 homes with single occupants, we were able to automatically detect mild cognitive impairment in older adults with an F0.5 score of 0.856. Also, we were able to detect the non-amnestic sub-type of mild cognitive impairment in older adults with an F0.5 score of 0.958.

  4. Highly Efficient State-Selective Submicrosecond Photoionization Detection of Single Atoms

    SciTech Connect

    Henkel, F.; Krug, M.; Hofmann, J.; Rosenfeld, W.; Weber, M.; Weinfurter, H.

    2010-12-17

    We experimentally demonstrate a detection scheme suitable for state analysis of single optically trapped atoms in less than 1 {mu}s with an overall detection efficiency {eta} exceeding 98%. The method is based on hyperfine-state-selective photoionization and subsequent registration of the correlated photoion-electron pairs by coincidence counting via two opposing channel electron multipliers. The scheme enables the calibration of absolute detection efficiencies and might be a key ingredient for future quantum information applications or precision spectroscopy of ultracold atoms.

  5. Fall detection in homes of older adults using the Microsoft Kinect.

    PubMed

    Stone, Erik E; Skubic, Marjorie

    2015-01-01

    A method for detecting falls in the homes of older adults using the Microsoft Kinect and a two-stage fall detection system is presented. The first stage of the detection system characterizes a person's vertical state in individual depth image frames, and then segments on ground events from the vertical state time series obtained by tracking the person over time. The second stage uses an ensemble of decision trees to compute a confidence that a fall preceded on a ground event. Evaluation was conducted in the actual homes of older adults, using a combined nine years of continuous data collected in 13 apartments. The dataset includes 454 falls, 445 falls performed by trained stunt actors and nine naturally occurring resident falls. The extensive data collection allows for characterization of system performance under real-world conditions to a degree that has not been shown in other studies. Cross validation results are included for standing, sitting, and lying down positions, near (within 4 m) versus far fall locations, and occluded versus not occluded fallers. The method is compared against five state-of-the-art fall detection algorithms and significantly better results are achieved. PMID:24733032

  6. Clinical Dementia Rating Scale Detects White Matter Changes in Older Adults at Risk for Alzheimer's Disease.

    PubMed

    Chang, Yu-Ling; Yen, Yu-Shiuan; Chen, Ta-Fu; Yan, Sui-Hing; Tseng, Wen-Yih Isaac

    2015-01-01

    This study investigated the putative changes in regional gray matter and cingulum bundle segments in mild cognitive impairment (MCI) by using two diagnostic criteria. Participants comprised 50 older adults with MCI and 22 healthy older controls (HC). The older adults with MCI were further divided into two groups defined by a global Clinical Dementia Rating (CDR) score of 0.5 and with (the CDR/NPT MCI group) or without (the CDR MCI group) objective cognitive impairments determined using neuropsychological tests (NPTs). Comparable regional gray matter integrity was observed among the three groups. However, the integrity of the right inferior segment of the cingulum bundle in the two MCI groups was more reduced than that in the HC group, and the CDR/NPT MCI group exhibited additional disruption in the left inferior cingulum bundle. The results also demonstrated that neuropsychological measures have greater predictive value for changes in white matter beyond the contribution of an informant-based instrument alone. Overall, the findings confirm the utility of informant-based assessment in detecting microstructural brain changes in high-risk older adults, even before objective cognitive impairment is evident. The findings also suggest that combining the neuropsychological measures with the informant-based assessment provided the greatest predictive value in assessing white matter disruption. The essential role of the white matter measurement as a biomarker for detecting individuals at a high risk of developing dementia was highlighted.

  7. Fall Detection Devices and their Use with Older Adults: A Systematic Review

    PubMed Central

    Chaudhuri, Shomir; Thompson, Hilaire; Demiris, George

    2013-01-01

    Background Falls represent a significant threat to the health and independence of adults 65 years of age and older. As a wide variety and large amount of passive monitoring systems are currently and increasingly available to detect when an individual has fallen, there is a need to analyze and synthesize the evidence regarding their ability to accurately detect falls to determine which systems are most effective. Objectives The purpose of this literature review is to systematically assess the current state of design and implementation of fall detection devices. This review also examines the extent to which these devices have been tested in the real world as well as the acceptability of these devices to older adults. Data sources A systematic literature review was conducted in PubMed, CINAHL, EMBASE and PsycINFO from their respective inception dates to June 25, 2013. Study Eligibility Criteria and Interventions Articles were included if they discussed a project or multiple projects involving a system with the purpose of detecting a fall in adults. It was not a requirement for inclusion in this review that the system targets persons over the age of 65. Articles were excluded if they were not written in English or if they looked at fall risk, fall detection in children, fall prevention or a Personal Emergency Response device. Study appraisal and synthesis methods Studies were initially divided into those using sensitivity, specificity or accuracy in their evaluation methods, and those using other methods to evaluate their devices. Studies were further classified into wearable devices and non-wearable devices. Studies were appraised for inclusion of older adults in sample and if evaluation included real world settings. Results This review identified 57 projects that used wearable systems and 35 projects using non-wearable systems, regardless of evaluation technique. Non-wearable systems included cameras, motion sensors, microphones and floor sensors. Of the projects

  8. Application of the EXtrapolated Efficiency Method (EXEM) to infer the gamma-cascade detection efficiency in the actinide region

    NASA Astrophysics Data System (ADS)

    Ducasse, Q.; Jurado, B.; Mathieu, L.; Marini, P.; Morillon, B.; Aiche, M.; Tsekhanovich, I.

    2016-08-01

    The study of transfer-induced gamma-decay probabilities is very useful for understanding the surrogate-reaction method and, more generally, for constraining statistical-model calculations. One of the main difficulties in the measurement of gamma-decay probabilities is the determination of the gamma-cascade detection efficiency. In Boutoux et al. (2013) [10] we developed the EXtrapolated Efficiency Method (EXEM), a new method to measure this quantity. In this work, we have applied, for the first time, the EXEM to infer the gamma-cascade detection efficiency in the actinide region. In particular, we have considered the 238U(d,p)239U and 238U(3He,d)239Np reactions. We have performed Hauser-Feshbach calculations to interpret our results and to verify the hypothesis on which the EXEM is based. The determination of fission and gamma-decay probabilities of 239Np below the neutron separation energy allowed us to validate the EXEM.

  9. Effects of aging and distractors on detection of redundant visual targets and capacity: do older adults integrate visual targets differently than younger adults?

    PubMed

    Ben-David, Boaz M; Eidels, Ami; Donkin, Chris

    2014-01-01

    In the redundant target effect, participants respond faster with two (redundant) targets. We compared the magnitude of this effect in younger and older adults, with and without distractors, in a simple visual-detection task. We employed additional measures that allow non-parametric assessment of performance (Townsend's capacity coefficient) and parametric estimates (Linear Ballistic Accumulator model). Older participants' latencies were slower, especially in the presence of distractors, and their calculated capacity indicators increased with distractors. Parametric estimates indicated that these increases were generated by the older adults' increased difficulty in inhibiting the distractors, and not the results of either improved detection of redundant-targets, or of a generalized slowing of processing.

  10. Guidelines to indirectly measure and enhance detection efficiency of stationary PIT tag interrogation systems in streams

    USGS Publications Warehouse

    Connolly, Patrick J.; Wolf, Keith; O'Neal, Jennifer S.

    2010-01-01

    With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.

  11. Detection efficiency evaluation for a large area neutron sensitive microchannel plate detector

    NASA Astrophysics Data System (ADS)

    Wang, Yi-ming; Tian, Yang; Yang, Yi-gang; Liu, Ren; Pan, Jing-sheng; Wang, Xue-wu; Zhang, Zhi

    2016-09-01

    In this paper, the detection efficiency of a large area neutron sensitive microchannel plate detector has been evaluated. A 6LiF/ZnS scintillator detector 65 mm in diameter and 0.32 mm in thickness, with product code, EJ426HD2, produced by Eljen Technology, was employed as the benchmark detector. The TOF spectra of these two detectors were simultaneously measured and the energy spectra were then deduced to calculate the detection efficiency curve of the nMCP detector. Tests show the detection efficiency@25.3 meV thermal neutrons is 34% for this nMCP detector. Supported by National Natural Science Foundation of China (11375095, 11175098)

  12. An efficient tree classifier ensemble-based approach for pedestrian detection.

    PubMed

    Xu, Yanwu; Cao, Xianbin; Qiao, Hong

    2011-02-01

    Classification-based pedestrian detection systems (PDSs) are currently a hot research topic in the field of intelligent transportation. A PDS detects pedestrians in real time on moving vehicles. A practical PDS demands not only high detection accuracy but also high detection speed. However, most of the existing classification-based approaches mainly seek for high detection accuracy, while the detection speed is not purposely optimized for practical application. At the same time, the performance, particularly the speed, is primarily tuned based on experiments without theoretical foundations, leading to a long training procedure. This paper starts with measuring and optimizing detection speed, and then a practical classification-based pedestrian detection solution with high detection speed and training speed is described. First, an extended classification/detection speed metric, named feature-per-object (fpo), is proposed to measure the detection speed independently from execution. Then, an fpo minimization model with accuracy constraints is formulated based on a tree classifier ensemble, where the minimum fpo can guarantee the highest detection speed. Finally, the minimization problem is solved efficiently by using nonlinear fitting based on radial basis function neural networks. In addition, the optimal solution is directly used to instruct classifier training; thus, the training speed could be accelerated greatly. Therefore, a rapid and accurate classification-based detection technique is proposed for the PDS. Experimental results on urban traffic videos show that the proposed method has a high detection speed with an acceptable detection rate and a false-alarm rate for onboard detection; moreover, the training procedure is also very fast.

  13. Rapid and efficient detection of single chromophore molecules in aqueous solution

    NASA Astrophysics Data System (ADS)

    Li, Li-Qiang; Davis, Lloyd M.

    1995-06-01

    The first experiments on the detection of single fluorescent molecules in a flowing stream of an aqueous solution with high total efficiency are reported. A capillary injection system for sample delivery causes all the dye molecules to pass in a diffusion-broadened stream within a fast-moving sheath flow, through the center of the tightly focused laser excitation beam. Single-molecule detection with a transit time of approximately 1 ms is accomplished with a high-quantum-efficiency single-photon avalanche diode and a low dead-time time-gating circuit for discrimination of Raman-scattered light from the solvent.

  14. Minimum detection efficiencies for a loophole-free observable-asymmetric Bell-type test

    SciTech Connect

    Garbarino, G.

    2010-03-15

    We discuss the problem of finding the most favorable conditions for closing the detection loophole in a test of local realism with a Bell inequality. For a generic nonmaximally entangled two-qubit state and two incompatible bases to be adopted for alternative measurements of two observables a and b on each party, we apply Hardy's proof of nonlocality without inequality and derive an Eberhard-like inequality. For an infinity of nonmaximally entangled states we find that it is possible to refute local realism by requiring perfect detection efficiency for only one of the two observables, say b, to be measured on each party: The test is free from the detection loophole for any value of the detection efficiency corresponding to the other observable a. The maximum tolerable noise in such a loophole-free observable-asymmetric test is also evaluated.

  15. Detection and Proportion of Very Early Dental Caries in Independent Living Older Adults

    PubMed Central

    Holtzman, Jennifer S.; Kohanchi, Daniel; Biren-Fetz, John; Fontana, Margherita; Ramchandani, Manisha; Osann, Kathryn; Hallajian, Lucy; Mansour, Stephanie; Nabelsi, Tasneem; Chung, Na Eun; Wilder-Smith, Petra

    2015-01-01

    Background and Objectives Dental caries is an important healthcare challenge in adults over 65 years of age. Integration of oral health screening into non-dental primary care practice may improve access to preventive dental care for vulnerable populations such as the elderly. Such integration would require easy, fast, and accurate early caries detection tools. Primary goal of this study was to evaluate the diagnostic performance of optical coherence tomography (OCT) imaging for detecting very early caries in the elderly living in community-based settings. The International Caries Detection and Assessment System (ICDAS) served as gold standard. Secondary goal of this study was to provide baseline prevalence data of very early caries lesions in independent living adults aged 65+ years. Materials and Methods Seventy-two subjects were recruited from three sites in Southern California: a retirement community, a senior health fair, and a convalescent hospital. Clinical examination was performed using the ICDAS visual criteria and this was followed by OCT imaging. The two-dimensional OCT images (B-scan) were analyzed with simple software. Locations with a log of back-scattered light intensity (BSLI) below 2.9 were scored as sound, and areas equaling or exceeding 2.9 BSLI were considered carious. Diagnostic performance of OCT imaging was compared with ICDAS score. Results OCT-based diagnosis demonstrated very good sensitivity (95.1%) and good specificity (85.8%). 54.7% of dentate subjects had at least one tooth with very early coronal caries. Conclusions Early coronal decay is prevalent in the unrestored pits and fissures of coronal surfaces of teeth in independent living adults aged 65+ years. Though OCT imaging coupled with a simple diagnostic algorithm can accurately detect areas of very early caries in community-based settings, existing devices are expensive and not well-suited for use by non-dental health care providers. Simple, inexpensive, fast, and accurate tools

  16. Nasopharyngeal versus oropharyngeal sampling for detection of pneumococcal carriage in adults.

    PubMed

    Watt, James P; O'Brien, Katherine L; Katz, Scott; Bronsdon, Melinda A; Elliott, John; Dallas, Jean; Perilla, Mindy J; Reid, Raymond; Murrow, Laurel; Facklam, Richard; Santosham, Mathuram; Whitney, Cynthia G

    2004-11-01

    Several studies have shown that nasopharyngeal sampling is more sensitive than oropharyngeal sampling for the detection of pneumococcal carriage in children. The data for adults are limited and conflicting. This study was part of a larger study of pneumococcal carriage on the Navajo and White Mountain Apache Reservation following a clinical trial of a seven-valent pneumococcal conjugate vaccine. Persons aged 18 years and older living in households with children enrolled in the vaccine trial were eligible. We collected both nasopharyngeal and oropharyngeal specimens by passing a flexible calcium alginate wire swab either nasally to the posterior nasopharynx or orally to the posterior oropharynx. Swabs were placed in skim milk-tryptone-glucose-glycerin medium and frozen at -70 degrees C. Pneumococcal isolation was performed by standard techniques. Analyses were based on specimens collected from 1,994 adults living in 1,054 households. Nasopharyngeal specimens (11.1%; 95% confidence interval [CI], 9.8 and 12.6%) were significantly more likely to grow pneumococci than were oropharyngeal specimens (5.8%; 95% CI, 4.8 to 6.9%) (P < 0.0001). Few persons had pneumococcal growth from both specimens (1.7%). Therefore, both tests together were more likely to identify pneumococcal carriage (15.2%; 95% CI, 13.7 to 16.9%) than either test alone. Although we found that nasopharyngeal sampling was more sensitive than oropharyngeal sampling, nasopharyngeal sampling alone would have underestimated the prevalence of pneumococcal carriage in this adult population. Sampling both sites may give more accurate results than sampling either site alone in studies of pneumococcal carriage in adults. PMID:15528682

  17. Oral Human Papillomavirus Detection in Older Adults Who Have Human Immunodeficiency Virus Infection

    PubMed Central

    Fatahzadeh, Mahnaz; Schlecht, Nicolas F.; Chen, Zigui; Bottalico, Danielle; McKinney, Sharod; Ostoloza, Janae; Dunne, Anne; Burk, Robert D.

    2014-01-01

    Objective To evaluate reproducibility of oral rinse self-collection for HPV detection and investigate associations between oral HPV, oral lesions, immune and sociodemographic factors, we performed a cross-sectional study of older adults with HIV infection. Study Design We collected oral rinse samples from 52 subjects at two different times of day followed by an oral examination and interview. We identified HPV using PCR platforms optimized for detection of mucosal and cutaneous types. Results Eighty seven percent of individuals had oral HPV, of which 23% had oncogenic alpha, 40% had non-oncogenic alpha, and 46% had beta or gamma HPV. Paired oral specimens were concordant in all parameters tested. Significant associations observed for oral HPV with increased HIV viral load, hepatitis-C seropositivity, history of sexually transmitted diseases and lifetime number of sexual partners. Conclusions Oral cavity may be a reservoir of subclinical HPV in older adults who have HIV infection. Understanding natural history, transmission and potential implications of oral HPV warrants further investigations. PMID:23375488

  18. VirusDetect: An automated pipeline for efficient virus discovery using deep sequencing of small RNAs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate detection of viruses in plants and animals is critical for agriculture production and human health. Deep sequencing and assembly of virus-derived siRNAs has proven to be a highly efficient approach for virus discovery. However, to date no computational tools specifically designed for both k...

  19. Fiber-coupled nanowire photon counter at 1550 nm with 24% system detection efficiency.

    PubMed

    Hu, Xiaolong; Zhong, Tian; White, James E; Dauler, Eric A; Najafi, Faraz; Herder, Charles H; Wong, Franco N C; Berggren, Karl K

    2009-12-01

    We developed a fiber-coupled superconducting nanowire single-photon detector system in a close-cycled cryocooler and achieved 24% and 22% system detection efficiencies at wavelengths of 1550 and 1315 nm, respectively. The maximum dark count rate was approximately 1000 counts/s.

  20. Measurement and simulation of neutron detection efficiency in lead-scintillating fiber calorimeters

    NASA Astrophysics Data System (ADS)

    Anelli, M.; Bertolucci, S.; Bini, C.; Branchini, P.; Curceanu, C.; De Zorzi, G.; Di Domenico, A.; Di Micco, B.; Ferrari, A.; Fiore, S.; Gauzzi, P.; Giovannella, S.; Happacher, F.; Iliescu, M.; Martini, M.; Miscetti, S.; Nguyen, F.; Passeri, A.; Prokofiev, A.; Sciascia, B.; Sirghi, F.

    2009-12-01

    The overall detection efficiency to neutrons of a small prototype of the KLOE lead-scintillating fiber calorimeter has been measured at the neutron beam facility of The Svedberg Laboratory, TSL, Uppsala, in the kinetic energy range [5-175] MeV. The measurement of the neutron detection efficiency of a NE110 scintillator provided a reference calibration. At the lowest trigger threshold, the overall calorimeter efficiency ranges from 30% to 50%. This value largely exceeds the estimated 8-15% expected if the response were proportional only to the scintillator equivalent thickness. A detailed simulation of the calorimeter and of the TSL beam line has been performed with the FLUKA Monte Carlo code. First data-MC comparisons are encouraging and allow to disentangle a neutron halo component in the beam.

  1. An Energy efficient application specific integrated circuit for electrocardiogram feature detection and its potential for ambulatory cardiovascular disease detection.

    PubMed

    Jain, Sanjeev Kumar; Bhaumik, Basabi

    2016-03-01

    A novel algorithm based on forward search is developed for real-time electrocardiogram (ECG) signal processing and implemented in application specific integrated circuit (ASIC) for QRS complex related cardiovascular disease diagnosis. The authors have evaluated their algorithm using MIT-BIH database and achieve sensitivity of 99.86% and specificity of 99.93% for QRS complex peak detection. In this Letter, Physionet PTB diagnostic ECG database is used for QRS complex related disease detection. An ASIC for cardiovascular disease detection is fabricated using 130-nm CMOS high-speed process technology. The area of the ASIC is 0.5 mm(2). The power dissipation is 1.73 μW at the operating frequency of 1 kHz with a supply voltage of 0.6 V. The output from the ASIC is fed to their Android application that generates diagnostic report and can be sent to a cardiologist through email. Their ASIC result shows average failed detection rate of 0.16% for six leads data of 290 patients in PTB diagnostic ECG database. They also have implemented a low-leakage version of their ASIC. The ASIC dissipates only 45 pJ with a supply voltage of 0.9 V. Their proposed ASIC is most suitable for energy efficient telemetry cardiovascular disease detection system. PMID:27284458

  2. An Energy efficient application specific integrated circuit for electrocardiogram feature detection and its potential for ambulatory cardiovascular disease detection.

    PubMed

    Jain, Sanjeev Kumar; Bhaumik, Basabi

    2016-03-01

    A novel algorithm based on forward search is developed for real-time electrocardiogram (ECG) signal processing and implemented in application specific integrated circuit (ASIC) for QRS complex related cardiovascular disease diagnosis. The authors have evaluated their algorithm using MIT-BIH database and achieve sensitivity of 99.86% and specificity of 99.93% for QRS complex peak detection. In this Letter, Physionet PTB diagnostic ECG database is used for QRS complex related disease detection. An ASIC for cardiovascular disease detection is fabricated using 130-nm CMOS high-speed process technology. The area of the ASIC is 0.5 mm(2). The power dissipation is 1.73 μW at the operating frequency of 1 kHz with a supply voltage of 0.6 V. The output from the ASIC is fed to their Android application that generates diagnostic report and can be sent to a cardiologist through email. Their ASIC result shows average failed detection rate of 0.16% for six leads data of 290 patients in PTB diagnostic ECG database. They also have implemented a low-leakage version of their ASIC. The ASIC dissipates only 45 pJ with a supply voltage of 0.9 V. Their proposed ASIC is most suitable for energy efficient telemetry cardiovascular disease detection system.

  3. An Energy efficient application specific integrated circuit for electrocardiogram feature detection and its potential for ambulatory cardiovascular disease detection

    PubMed Central

    Bhaumik, Basabi

    2016-01-01

    A novel algorithm based on forward search is developed for real-time electrocardiogram (ECG) signal processing and implemented in application specific integrated circuit (ASIC) for QRS complex related cardiovascular disease diagnosis. The authors have evaluated their algorithm using MIT-BIH database and achieve sensitivity of 99.86% and specificity of 99.93% for QRS complex peak detection. In this Letter, Physionet PTB diagnostic ECG database is used for QRS complex related disease detection. An ASIC for cardiovascular disease detection is fabricated using 130-nm CMOS high-speed process technology. The area of the ASIC is 0.5 mm2. The power dissipation is 1.73 μW at the operating frequency of 1 kHz with a supply voltage of 0.6 V. The output from the ASIC is fed to their Android application that generates diagnostic report and can be sent to a cardiologist through email. Their ASIC result shows average failed detection rate of 0.16% for six leads data of 290 patients in PTB diagnostic ECG database. They also have implemented a low-leakage version of their ASIC. The ASIC dissipates only 45 pJ with a supply voltage of 0.9 V. Their proposed ASIC is most suitable for energy efficient telemetry cardiovascular disease detection system. PMID:27284458

  4. High efficiency processing for reduced amplitude zones detection in the HRECG signal

    NASA Astrophysics Data System (ADS)

    Dugarte, N.; Álvarez, A.; Balacco, J.; Mercado, G.; Gonzalez, A.; Dugarte, E.; Olivares, A.

    2016-04-01

    Summary - This article presents part of a more detailed research proposed in the medium to long term, with the intention of establishing a new philosophy of electrocardiogram surface analysis. This research aims to find indicators of cardiovascular disease in its early stage that may go unnoticed with conventional electrocardiography. This paper reports the development of a software processing which collect some existing techniques and incorporates novel methods for detection of reduced amplitude zones (RAZ) in high resolution electrocardiographic signal (HRECG).The algorithm consists of three stages, an efficient processing for QRS detection, averaging filter using correlation techniques and a step for RAZ detecting. Preliminary results show the efficiency of system and point to incorporation of techniques new using signal analysis with involving 12 leads.

  5. High efficiency processing for reduced amplitude zones detection in the HRECG signal

    NASA Astrophysics Data System (ADS)

    Dugarte, N.; Álvarez, A.; Balacco, J.; Mercado, G.; Gonzalez, A.; Dugarte, E.; Olivares, A.

    2016-04-01

    Summary – This article presents part of a more detailed research proposed in the medium to long term, with the intention of establishing a new philosophy of electrocardiogram surface analysis. This research aims to find indicators of cardiovascular disease in its early stage that may go unnoticed with conventional electrocardiography. This paper reports the development of a software processing which collect some existing techniques and incorporates novel methods for detection of reduced amplitude zones (RAZ) in high resolution electrocardiographic signal (HRECG).The algorithm consists of three stages, an efficient processing for QRS detection, averaging filter using correlation techniques and a step for RAZ detecting. Preliminary results show the efficiency of system and point to incorporation of techniques new using signal analysis with involving 12 leads.

  6. Efficiency of different strategies to detect autoantibodies to extractable nuclear antigens.

    PubMed

    Almeida González, Delia; Cabrera de León, Antonio; Rodríguez Pérez, María Del Cristo; Brito Díaz, Buenaventura; González Hernández, Ana; García García, Diego; Vázquez Moncholi, Carmen; Aguirre Jaime, Armando

    2010-08-31

    Autoantibodies to extractable nuclear antigens (anti-ENA) are identified mainly in samples positive for antinuclear antibodies (ANA). Although the method of choice for ANA screening is indirect immunofluorescence (IIF), several techniques are available to detect anti-ENA. The aim of this study was to compare the efficiency of five different strategies to determine anti-ENA. During a 2-year period we screened ANA in 30375 samples with IIF, and the 4475 samples ANA positive were tested for anti-ENA by double immune diffusion screening or fluoroenzymeimmunoassay (Screening FI); anti-ENA specificities were then determined by line immunoassay (LIA) or fluoroenzymeimmunoassay (FI). We compared five strategies that involved FI or LIA identification of anti-ENA with or without prior screening, or an algorithm that combined fluorescence pattern, number of anti-ENA specificities requested by the clinician and ANA dilution titer. One cost unit (CU) was defined as the cost of 1 test of ANA determination. We detected 553 anti-ENA positive samples. The most efficient strategy was the algorithm, at a cost of 3.3 CU per sample processed, the second most efficient strategy was screening plus FI identification (cost=3.8 CU), and the third most efficient strategy was screening plus LIA identification (cost=3.9 CU). The fourth most efficient strategy was FI identification without prior screening (13.3 CU per sample) and the least efficient was LIA identification without prior screening (13.6 CU per sample). In conclusion, an algorithm that combined techniques for detection, ANA titer, fluorescence pattern and number of specificities requested was the most efficient strategy for determining anti-ENA.

  7. Recombinant adeno-associated viral (rAAV) vectors mediate efficient gene transduction in cultured neonatal and adult microglia.

    PubMed

    Su, Wei; Kang, John; Sopher, Bryce; Gillespie, James; Aloi, Macarena S; Odom, Guy L; Hopkins, Stephanie; Case, Amanda; Wang, David B; Chamberlain, Jeffrey S; Garden, Gwenn A

    2016-01-01

    Microglia are a specialized population of myeloid cells that mediate CNS innate immune responses. Efforts to identify the cellular and molecular mechanisms that regulate microglia behaviors have been hampered by the lack of effective tools for manipulating gene expression. Cultured microglia are refractory to most chemical and electrical transfection methods, yielding little or no gene delivery and causing toxicity and/or inflammatory activation. Recombinant adeno-associated viral (rAAVs) vectors are non-enveloped, single-stranded DNA vectors commonly used to transduce many primary cell types and tissues. In this study, we evaluated the feasibility and efficiency of utilizing rAAV serotype 2 (rAAV2) to modulate gene expression in cultured microglia. rAAV2 yields high transduction and causes minimal toxicity or inflammatory response in both neonatal and adult microglia. To demonstrate that rAAV transduction can induce functional protein expression, we used rAAV2 expressing Cre recombinase to successfully excise a LoxP-flanked miR155 gene in cultured microglia. We further evaluated rAAV serotypes 5, 6, 8, and 9, and observed that all efficiently transduced cultured microglia to varying degrees of success and caused little or no alteration in inflammatory gene expression. These results provide strong encouragement for the application of rAAV-mediated gene expression in microglia for mechanistic and therapeutic purposes. Neonatal microglia are functionally distinct from adult microglia, although the majority of in vitro studies utilize rodent neonatal microglia cultures because of difficulties of culturing adult cells. In addition, cultured microglia are refractory to most methods for modifying gene expression. Here, we developed a novel protocol for culturing adult microglia and evaluated the feasibility and efficiency of utilizing Recombinant Adeno-Associated Virus (rAAV) to modulate gene expression in cultured microglia.

  8. Efficiency of Portable Antennas for Detecting Passive Integrated Transponder Tags in Stream-Dwelling Salmonids.

    PubMed

    Banish, Nolan P; Burdick, Summer M; Moyer, Katherine R

    2016-01-01

    Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout (Salmo trutta), bull trout (Salvelinus confluentus), and redband trout (Oncorhynchus mykiss newberrii) marked with 12-mm PIT tags. We redetected 56% (20/36) of brown trout, 34% (68/202) of bull trout, and 33% (20/61) of redband trout after a recovery period of 21 to 46 hours. Models indicate support for length and species and minor support for percent boulder, large woody debris, and percent cobble as parameters important for describing variation in detection efficiency, although 95% confidence intervals for estimates were large. The odds of detecting brown trout (1.5 ± 2.2 [mean ± SE]) are approximately four times as high as bull trout (0.4 ± 1.6) or redband trout (0.3 ± 1.8) and species-specific differences may be related to length. Our reported detection efficiency for brown trout falls within the range of other studies, but is the first reported for bull trout and redband trout. Portable antennas may be a relatively unbiased way of redetecting varying sizes of all three salmonid species. PMID:26901317

  9. Efficiency of portable antennas for detecting passive integrated transponder tags in stream-dwelling salmonids

    USGS Publications Warehouse

    Banish, Nolan P.; Burdick, Summer M.; Moyer, Katherine R.

    2016-01-01

    Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout (Salmo trutta), bull trout (Salvelinus confluentus), and redband trout (Oncorhynchus mykiss newberrii) marked with 12-mm PIT tags. We redetected 56% (20/36) of brown trout, 34% (68/202) of bull trout, and 33% (20/61) of redband trout after a recovery period of 21 to 46 hours. Models indicate support for length and species and minor support for percent boulder, large woody debris, and percent cobble as parameters important for describing variation in detection efficiency, although 95% confidence intervals for estimates were large. The odds of detecting brown trout (1.5 ± 2.2 [mean ± SE]) are approximately four times as high as bull trout (0.4 ± 1.6) or redband trout (0.3 ± 1.8) and species-specific differences may be related to length. Our reported detection efficiency for brown trout falls within the range of other studies, but is the first reported for bull trout and redband trout. Portable antennas may be a relatively unbiased way of redetecting varying sizes of all three salmonid species.

  10. Efficiency of Portable Antennas for Detecting Passive Integrated Transponder Tags in Stream-Dwelling Salmonids.

    PubMed

    Banish, Nolan P; Burdick, Summer M; Moyer, Katherine R

    2016-01-01

    Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout (Salmo trutta), bull trout (Salvelinus confluentus), and redband trout (Oncorhynchus mykiss newberrii) marked with 12-mm PIT tags. We redetected 56% (20/36) of brown trout, 34% (68/202) of bull trout, and 33% (20/61) of redband trout after a recovery period of 21 to 46 hours. Models indicate support for length and species and minor support for percent boulder, large woody debris, and percent cobble as parameters important for describing variation in detection efficiency, although 95% confidence intervals for estimates were large. The odds of detecting brown trout (1.5 ± 2.2 [mean ± SE]) are approximately four times as high as bull trout (0.4 ± 1.6) or redband trout (0.3 ± 1.8) and species-specific differences may be related to length. Our reported detection efficiency for brown trout falls within the range of other studies, but is the first reported for bull trout and redband trout. Portable antennas may be a relatively unbiased way of redetecting varying sizes of all three salmonid species.

  11. Efficiency of Portable Antennas for Detecting Passive Integrated Transponder Tags in Stream-Dwelling Salmonids

    PubMed Central

    Moyer, Katherine R.

    2016-01-01

    Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout (Salmo trutta), bull trout (Salvelinus confluentus), and redband trout (Oncorhynchus mykiss newberrii) marked with 12-mm PIT tags. We redetected 56% (20/36) of brown trout, 34% (68/202) of bull trout, and 33% (20/61) of redband trout after a recovery period of 21 to 46 hours. Models indicate support for length and species and minor support for percent boulder, large woody debris, and percent cobble as parameters important for describing variation in detection efficiency, although 95% confidence intervals for estimates were large. The odds of detecting brown trout (1.5 ± 2.2 [mean ± SE]) are approximately four times as high as bull trout (0.4 ± 1.6) or redband trout (0.3 ± 1.8) and species-specific differences may be related to length. Our reported detection efficiency for brown trout falls within the range of other studies, but is the first reported for bull trout and redband trout. Portable antennas may be a relatively unbiased way of redetecting varying sizes of all three salmonid species. PMID:26901317

  12. Differential efficiency among DNA extraction methods influences detection of the amphibian pathogen Batrachochytrium dendrobatidis.

    PubMed

    Bletz, M C; Rebollar, E A; Harris, R N

    2015-02-10

    Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is responsible for massive declines and extinctions of amphibians worldwide. The most common method for detecting Bd is quantitative polymerase chain reaction (qPCR). qPCR is a highly sensitive detection technique, but its ability to determine the presence and accurately quantify the amount of Bd is also contingent on the efficiency of the DNA extraction method used prior to PCR. Using qPCR, we compared the extraction efficiency of 3 different extraction methods commonly used for Bd detection across a range of zoospore quantities: PrepMan Ultra Reagent, Qiagen DNeasy Blood and Tissue Kit, and Mobio PowerSoil DNA Isolation Kit. We show that not all extraction methods led to successful detection of Bd for the low zoospore quantities and that there was variation in the estimated zoospore equivalents among the methods, which demonstrates that these methods have different extraction efficiencies. These results highlight the importance of considering the extraction method when comparing across studies. The Qiagen DNeasy kit had the highest efficiency. We also show that replicated estimates of less than 1 zoospore can result from known zoospore concentrations; therefore, such results should be considered when obtained from field data. Additionally, we discuss the implications of our findings for interpreting previous studies and for conducting future Bd surveys. It is imperative to use the most efficient DNA extraction method in tandem with the highly sensitive qPCR technique in order to accurately diagnose the presence of Bd as well as other pathogens.

  13. Efficiency of Airborne Sample Analysis Platform (ASAP) bioaerosol sampler for pathogen detection

    PubMed Central

    Sharma, Anurag; Clark, Elizabeth; McGlothlin, James D.; Mittal, Suresh K.

    2015-01-01

    The threat of bioterrorism and pandemics has highlighted the urgency for rapid and reliable bioaerosol detection in different environments. Safeguarding against such threats requires continuous sampling of the ambient air for pathogen detection. In this study we investigated the efficacy of the Airborne Sample Analysis Platform (ASAP) 2800 bioaerosol sampler to collect representative samples of air and identify specific viruses suspended as bioaerosols. To test this concept, we aerosolized an innocuous replication-defective bovine adenovirus serotype 3 (BAdV3) in a controlled laboratory environment. The ASAP efficiently trapped the surrogate virus at 5 × 103 plaque-forming units (p.f.u.) [2 × 105 genome copy equivalent] concentrations or more resulting in the successful detection of the virus using quantitative PCR. These results support the further development of ASAP for bioaerosol pathogen detection. PMID:26074900

  14. The OGLE-III planet detection efficiency from six years of microlensing observations (2003-2008)

    NASA Astrophysics Data System (ADS)

    Tsapras, Y.; Hundertmark, M.; Wyrzykowski, Ł.; Horne, K.; Udalski, A.; Snodgrass, C.; Street, R.; Bramich, D. M.; Dominik, M.; Bozza, V.; Figuera Jaimes, R.; Kains, N.; Skowron, J.; Szymański, M. K.; Pietrzyński, G.; Soszyński, I.; Ulaczyk, K.; Kozłowski, S.; Pietrukowicz, P.; Poleski, R.

    2016-04-01

    We use six years (2003-2008) of Optical Gravitational Lensing Experiment-III microlensing observations to derive the survey detection efficiency for a range of planetary masses and projected distances from the host star. We perform an independent analysis of the microlensing light curves to extract the event parameters and compute the planet detection probability given the data. 2433 light curves satisfy our quality selection criteria and are retained for further processing. The aggregate of the detection probabilities over the range explored yields the expected number of microlensing planet detections. We employ a Galactic model to convert this distribution from dimensionless to physical units, α/au and M⊕. The survey sensitivity to small planets is highest in the range 1-4 au, shifting to slightly larger separations for more massive ones.

  15. Measurement and simulation of the neutron detection efficiency with a Pb-scintillating fiber calorimeter

    NASA Astrophysics Data System (ADS)

    Anelli, M.; Battistoni, G.; Bertolucci, S.; Bini, C.; Branchini, P.; Curceanu, C.; DeZorzi, G.; Domenico, Adi; Di Micco, B.; Ferrari, A.; Fiore, S.; Gauzzi, P.; Giovannella, S.; Happacher, F.; Iliescu, M.; Martini, M.; Miscetti, S.; Ngugen, F.; Paseri, A.; Prokfiev, A.; Sala, P.; Sciascia, B.; Sirghi, F.

    2009-04-01

    We have measured the overall detection efficiency of a small prototype of the KLOE PB-scintilation fiber calorimeter to neutrons with kinetic energy range [5,175] MeV. The measurement has been done in a dedicated test beam in the neutron beam facility of the Svedberg Laboratory, TSL Uppsala. The measurements of the neutron detection efficiency of a NE110 scintillator provided a reference calibration. At the lowest trigger threshold, the overall calorimeter efficiency ranges from 28% to 33%. This value largely exceeds the estimated ~8% expected if the response were proporetional only to the scintillator equivalent thickness. A detailed simulation of the calorimeter and of the TSL beam line has been performed with the FLUKA Monte Carlo code. The simulated response of the detector to neutrons is presented together with the first data to Monte Carlo comparison. The results show an overall neutron efficiency of about 35%. The reasons for such an efficiency enhancement, in comparison with the typical scintillator-based neutron counters, are explained, opening the road to a novel neutron detector.

  16. Determining the Detection Efficiency and Background Level of ATIC Electron Observation from Flight Data

    NASA Technical Reports Server (NTRS)

    Chang, J.; Wu, J.; Guzik, T. G.; Wefel, J. P.; Isbert, J.; Adams, J. H., Jr.; Christl, M.; Watts, J.; Ahn, H. S.; Kim, K. C.; Seo, E. S.; Wu, J.; Bashindzhagyan, G. L.; Kouznetsov, E. N.; Panasyuk, M. I.; Sokolskaya, N. V.; Panov, A. D.; Zatsepin, V. I.

    2009-01-01

    Observations of Cosmic-ray electrons are difficult due to the large flux of cosmic ray hadrons. The event selection efficiency and background levels can be estimated from flight data for the ATIC instrument. This reduces the dependence upon Monte Carlo simulations, which show differences between different codes, thereby reducing the systematic errors resulting from analyses that only use simulations. This paper discusses some of the methods used in the ATIC analysis to determine the detection efficiency and background level for the flight data.

  17. Combined DECS Analysis and Next-Generation Sequencing Enable Efficient Detection of Novel Plant RNA Viruses.

    PubMed

    Yanagisawa, Hironobu; Tomita, Reiko; Katsu, Koji; Uehara, Takuya; Atsumi, Go; Tateda, Chika; Kobayashi, Kappei; Sekine, Ken-Taro

    2016-03-01

    The presence of high molecular weight double-stranded RNA (dsRNA) within plant cells is an indicator of infection with RNA viruses as these possess genomic or replicative dsRNA. DECS (dsRNA isolation, exhaustive amplification, cloning, and sequencing) analysis has been shown to be capable of detecting unknown viruses. We postulated that a combination of DECS analysis and next-generation sequencing (NGS) would improve detection efficiency and usability of the technique. Here, we describe a model case in which we efficiently detected the presumed genome sequence of Blueberry shoestring virus (BSSV), a member of the genus Sobemovirus, which has not so far been reported. dsRNAs were isolated from BSSV-infected blueberry plants using the dsRNA-binding protein, reverse-transcribed, amplified, and sequenced using NGS. A contig of 4,020 nucleotides (nt) that shared similarities with sequences from other Sobemovirus species was obtained as a candidate of the BSSV genomic sequence. Reverse transcription (RT)-PCR primer sets based on sequences from this contig enabled the detection of BSSV in all BSSV-infected plants tested but not in healthy controls. A recombinant protein encoded by the putative coat protein gene was bound by the BSSV-antibody, indicating that the candidate sequence was that of BSSV itself. Our results suggest that a combination of DECS analysis and NGS, designated here as "DECS-C," is a powerful method for detecting novel plant viruses. PMID:27072419

  18. Combined DECS Analysis and Next-Generation Sequencing Enable Efficient Detection of Novel Plant RNA Viruses

    PubMed Central

    Yanagisawa, Hironobu; Tomita, Reiko; Katsu, Koji; Uehara, Takuya; Atsumi, Go; Tateda, Chika; Kobayashi, Kappei; Sekine, Ken-Taro

    2016-01-01

    The presence of high molecular weight double-stranded RNA (dsRNA) within plant cells is an indicator of infection with RNA viruses as these possess genomic or replicative dsRNA. DECS (dsRNA isolation, exhaustive amplification, cloning, and sequencing) analysis has been shown to be capable of detecting unknown viruses. We postulated that a combination of DECS analysis and next-generation sequencing (NGS) would improve detection efficiency and usability of the technique. Here, we describe a model case in which we efficiently detected the presumed genome sequence of Blueberry shoestring virus (BSSV), a member of the genus Sobemovirus, which has not so far been reported. dsRNAs were isolated from BSSV-infected blueberry plants using the dsRNA-binding protein, reverse-transcribed, amplified, and sequenced using NGS. A contig of 4,020 nucleotides (nt) that shared similarities with sequences from other Sobemovirus species was obtained as a candidate of the BSSV genomic sequence. Reverse transcription (RT)-PCR primer sets based on sequences from this contig enabled the detection of BSSV in all BSSV-infected plants tested but not in healthy controls. A recombinant protein encoded by the putative coat protein gene was bound by the BSSV-antibody, indicating that the candidate sequence was that of BSSV itself. Our results suggest that a combination of DECS analysis and NGS, designated here as “DECS-C,” is a powerful method for detecting novel plant viruses. PMID:27072419

  19. Efficient and robust quantum random number generation by photon number detection

    SciTech Connect

    Applegate, M. J.; Thomas, O.; Dynes, J. F.; Yuan, Z. L.; Shields, A. J.; Ritchie, D. A.

    2015-08-17

    We present an efficient and robust quantum random number generator based upon high-rate room temperature photon number detection. We employ an electric field-modulated silicon avalanche photodiode, a type of device particularly suited to high-rate photon number detection with excellent photon number resolution to detect, without an applied dead-time, up to 4 photons from the optical pulses emitted by a laser. By both measuring and modeling the response of the detector to the incident photons, we are able to determine the illumination conditions that achieve an optimal bit rate that we show is robust against variation in the photon flux. We extract random bits from the detected photon numbers with an efficiency of 99% corresponding to 1.97 bits per detected photon number yielding a bit rate of 143 Mbit/s, and verify that the extracted bits pass stringent statistical tests for randomness. Our scheme is highly scalable and has the potential of multi-Gbit/s bit rates.

  20. Associate investigations: detection of tuberculosis infections in children resulting in discovery of undiagnosed tuberculosis in adults.

    PubMed

    Moonan, Patrick K; Quitugua, Teresa; Cox, Rebecca A; Weis, Stephen E

    2002-07-01

    The authors present the design and implementation of associate investigations of young children with positive tuberculin skin test results. Case study analysis of an associate investigation was done using epidemiologic surveillance techniques, medical interviewing, sociogram mapping, tuberculin skin testing, radiographic evidence, and bacteriologic analysis. Deoxyribonucleic acid fingerprinting of the Mycobacterium tuberculosis isolates using a standardized IS6110-based restriction fragment length polymorphism analysis and IS6110-independent DNA spoligotyping methods was done to track and identify specific bacterial strains. Deoxyribonucleic acid fingerprinting and spoligotyping done on isolates obtained from family members demonstrated same-strain transmission of M. tuberculosis. Three adults with active pulmonary disease and six individuals with latent tuberculosis (TB) were discovered during this investigation. The arrival of a family member from Mexico who had the same strain suggests that the source case lives in Mexico. A child with positive tuberculin skin test results indicates recent and potentially ongoing transmission of TB in the community. Targeted tuberculin skin testing performed on high-risk groups by primary care physicians allows for detection of TB infections. When TB infections are discovered in children, associate investigations can result in the discovery of undiagnosed adult cases and prevent further transmission within the community.

  1. Hyper sensitive protein detection by Tandem-HTRF reveals Cyclin D1 dynamics in adult mouse

    PubMed Central

    Zampieri, Alexandre; Champagne, Julien; Auzemery, Baptiste; Fuentes, Ivanna; Maurel, Benjamin; Bienvenu, Frédéric

    2015-01-01

    We present here a novel method for the semi-quantitative detection of low abundance proteins in solution that is both fast and simple. It is based on Homogenous Time Resolved Förster Resonance Energy Transfer (HTRF), between a lanthanide labeled donor antibody and a d2 or XL665 labeled acceptor antibody that are both raised against different epitopes of the same target. This novel approach we termed “Tandem-HTRF”, can specifically reveal rare polypeptides from only a few microliters of cellular lysate within one hour in a 384-well plate format. Using this sensitive approach, we observed surprisingly that the core cell cycle regulator Cyclin D1 is sustained in fully developed adult organs and harbors an unexpected expression pattern affected by environmental challenge. Thus our method, Tandem-HTRF offers a promising way to investigate subtle variations in the dynamics of sparse proteins from limited biological material. PMID:26503526

  2. Monocular perceptual learning of contrast detection facilitates binocular combination in adults with anisometropic amblyopia

    PubMed Central

    Chen, Zidong; Li, Jinrong; Liu, Jing; Cai, Xiaoxiao; Yuan, Junpeng; Deng, Daming; Yu, Minbin

    2016-01-01

    Perceptual learning in contrast detection improves monocular visual function in adults with anisometropic amblyopia; however, its effect on binocular combination remains unknown. Given that the amblyopic visual system suffers from pronounced binocular functional loss, it is important to address how the amblyopic visual system responds to such training strategies under binocular viewing conditions. Anisometropic amblyopes (n = 13) were asked to complete two psychophysical supra-threshold binocular summation tasks: (1) binocular phase combination and (2) dichoptic global motion coherence before and after monocular training to investigate this question. We showed that these participants benefited from monocular training in terms of binocular combination. More importantly, the improvements observed with the area under log CSF (AULCSF) were found to be correlated with the improvements in binocular phase combination. PMID:26829898

  3. Immunochemical detection of arylamine N-acetyltransferase during mouse embryonic development and in adult mouse brain.

    PubMed

    Stanley, L A; Copp, A J; Pope, J; Rolls, S; Smelt, V; Perry, V H; Sim, E

    1998-11-01

    Arylamine N-acetyltransferases (NATs) are important in susceptibility to xenobiotic-induced disorders (e.g., drug-induced autoimmune disease, bladder cancer), but their role in endogenous metabolism is yet to be elucidated. The discovery that human NAT1 acts upon p-aminobenzoylgluatamate (p-ABG) to generate p-acetamidobenzoylglutamate (p-AABG), a major urinary metabolite of folic acid, suggests that human NAT1 may play a role in folic acid metabolism and hence in the normal development of the neural tube. In this study we examined the distribution of NAT in neuronal tissue from adult mice and embryos. Immunohistochemical staining of the adult mouse cerebellum revealed NAT2 (the mouse homologue of human NAT1) expression in the cell bodies and dendrites of Purkinje cells and in the neuroglia of the molecular layer. In embryos, NAT2 was detected in developing neuronal tissue on days 9.5, 11.5, and 13.5. It was expressed intensely in the nerual tube around the time of closure. The level of expression subsequently declined in the neuroepithelium but increased in glial cells. In addition, NAT2 was detected in the developing heart and gut. These findings demonstrate that the embryo itself expresses an enzyme which is involved in the metabolism of folic acid, so that the role played by both mother and embryo must be considered when examining the role of folic acid in embryonic development. These findings imply that polymorphisms in NAT genes could play a role in determining susceptibility to neural tube defects (NTD) and orofacial clefting, developmental disorders which can be prevented by dietary administration of folic acid. PMID:9839355

  4. Detection of Cardiovascular Disease Risk's Level for Adults Using Naive Bayes Classifier

    PubMed Central

    Miranda, Eka; Amelga, Alowisius Y.; Maribondang, Marco M.; Salim, Mulyadi

    2016-01-01

    Objectives The number of deaths caused by cardiovascular disease and stroke is predicted to reach 23.3 million in 2030. As a contribution to support prevention of this phenomenon, this paper proposes a mining model using a naïve Bayes classifier that could detect cardiovascular disease and identify its risk level for adults. Methods The process of designing the method began by identifying the knowledge related to the cardiovascular disease profile and the level of cardiovascular disease risk factors for adults based on the medical record, and designing a mining technique model using a naïve Bayes classifier. Evaluation of this research employed two methods: accuracy, sensitivity, and specificity calculation as well as an evaluation session with cardiologists and internists. The characteristics of cardiovascular disease are identified by its primary risk factors. Those factors are diabetes mellitus, the level of lipids in the blood, coronary artery function, and kidney function. Class labels were assigned according to the values of these factors: risk level 1, risk level 2 and risk level 3. Results The evaluation of the classifier performance (accuracy, sensitivity, and specificity) in this research showed that the proposed model predicted the class label of tuples correctly (above 80%). More than eighty percent of respondents (including cardiologists and internists) who participated in the evaluation session agree till strongly agreed that this research followed medical procedures and that the result can support medical analysis related to cardiovascular disease. Conclusions The research showed that the proposed model achieves good performance for risk level detection of cardiovascular disease. PMID:27525161

  5. High efficiency Hall effect micro-biosensor platform for detection of magnetically labeled biomolecules.

    PubMed

    Sandhu, Adarsh; Kumagai, Yoshimichi; Lapicki, Adam; Sakamoto, Satoshi; Abe, Masanori; Handa, Hiroshi

    2007-04-15

    Detection of magnetically labeled biomolecules using micro-Hall biosensors is a promising method for monitoring biomolecular recognition processes. The measurement efficiency of standard systems is limited by the time taken for magnetic beads to reach the sensing area of the Hall devices. Here, micro-current lines were integrated with Hall effect structures to manipulate the position of magnetic beads via field gradients generated by localized currents flowing in the current lines. Beads were accumulated onto the sensor surface within seconds of passing currents through the current lines. Real-time detection of magnetic beads using current lines integrated with Hall biosensors was achieved. These results are promising in establishing Hall biosensor platforms as efficient and inexpensive means of monitoring biomolecular reactions for medical applications.

  6. Ion generation and CPC detection efficiency studies in sub 3-nm size range

    SciTech Connect

    Kangasluoma, J.; Junninen, H.; Sipilae, M.; Kulmala, M.; Petaejae, T.; Lehtipalo, K.; Mikkilae, J.; Vanhanen, J.; Attoui, M.; Worsnop, D.

    2013-05-24

    We studied the chemical composition of commonly used condensation particle counter calibration ions with a mass spectrometer and found that in our calibration setup the negatively charged ammonium sulphate, sodium chloride and tungsten oxide are the least contaminated whereas silver on both positive and negative and the three mentioned earlier in positive mode are contaminated with organics. We report cut-off diameters for Airmodus Particle Size Magnifier (PSM) 1.1, 1.3, 1.4, 1.6 and 1.6-1.8 nm for negative sodium chloride, ammonium sulphate, tungsten oxide, silver and positive organics, respectively. To study the effect of sample relative humidity on detection efficiency of the PSM we used different humidities in the differential mobility analyzer sheath flow and found that with increasing relative humidity also the detection efficiency of the PSM increases.

  7. A Luminescent Hypercrosslinked Conjugated Microporous Polymer for Efficient Removal and Detection of Mercury Ions.

    PubMed

    Xiang, Lu; Zhu, Yunlong; Gu, Shuai; Chen, Dongyang; Fu, Xian; Zhang, Yindong; Yu, Guipeng; Pan, Chunyue; Hu, Yuehua

    2015-09-01

    A hypercrosslinked conjugated microporous polymer (HCMP-1) with a robustly efficient absorption and highly specific sensitivity to mercury ions (Hg(2+)) is synthesized in a one-step Friedel-Crafts alkylation of cost-effective 2,4,6-trichloro-1,3,5-triazine and dibenzofuran in 1,2-dichloroethane. HCMP-1 has a moderate Brunauer-Emmett-Teller specific surface (432 m(2) g(-1)), but it displays a high adsorption affinity (604 mg g(-1)) and excellent trace efficiency for Hg(2+). The π-π* electronic transition among the aromatic heterocyclic rings endows HCMP-1 a strong fluorescent property and the fluorescence is obviously weakened after Hg(2+) uptake, which makes the hypercrosslinked conjugated microporous polymer a promising fluorescent probe for Hg(2+) detection, owning a super-high sensitivity (detection limit 5 × 10(-8) mol L(-1)). PMID:26088466

  8. Mass measurement of a single unseen star and planetary detection efficiency for OGLE 2007-BLG-050

    NASA Astrophysics Data System (ADS)

    Batista, V.; Dong, S.; Gould, A.; Beaulieu, J. P.; Cassan, A.; Christie, G. W.; Han, C.; Udalski, A.; Allen, W.; Depoy, D. L.; Gal-Yam, A.; Gaudi, B. S.; Johnson, B.; Kaspi, S.; Lee, C. U.; Maoz, D.; McCormick, J.; McGreer, I.; Monard, B.; Natusch, T.; Ofek, E.; Park, B.-G.; Pogge, R. W.; Polishook, D.; Shporer, A.; μFUN Collaboration; Albrow, M. D.; Bennett, D. P.; Brillant, S.; Bode, M.; Bramich, D. M.; Burgdorf, M.; Caldwell, J. A. R.; Calitz, H.; Cole, A.; Cook, K. H.; Coutures, Ch.; Dieters, S.; Dominik, M.; Prester, D. D.; Donatowicz, J.; Fouqué, P.; Greenhill, J.; Hoffman, M.; Horne, K.; Jørgensen, U. G.; Kains, N.; Kane, S.; Kubas, D.; Marquette, J. B.; Martin, R.; Meintjes, P.; Menzies, J.; Pollard, K. R.; Sahu, K. C.; Snodgrass, C.; Steele, I.; Tsapras, Y.; Wambsganss, J.; Williams, A.; Zub, M.; PLANET/RoboNet Collaboration; Wyrzykowski, Ł.; Kubiak, M.; Szymański, M. K.; Pietrzyński, G.; Soszyński, I.; Szewczyk, O.; Ulaczyk, K.; Ogle Collaboration; Abe, F.; Bond, I. A.; Fukui, A.; Furusawa, K.; Hearnshaw, J. B.; Holderness, S.; Itow, Y.; Kamiya, K.; Kilmartin, P. M.; Korpela, A.; Lin, W.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y.; Nagaya, M.; Ohnishi, K.; Okumura, T.; Perrott, Y. C.; Rattenbury, N.; Saito, T.; Sako, T.; Skuljan, L.; Sullivan, D.; Sumi, T.; Sweatman, W. L.; Tristram, P. J.; Yock, P. C. M.; MOA Collaboration

    2009-12-01

    Aims. We analyze OGLE-2007-BLG-050, a high magnification microlensing event (A˜ 432) whose peak occurred on 2 May, 2007, with pronounced finite-source and parallax effects. We compute planet detection efficiencies for this event in order to determine its sensitivity to the presence of planets around the lens star. Methods: Both finite-source and parallax effects permit a measurement of the angular Einstein radius θ_E=0.48± 0.01 mas and the parallax π_E=0.12± 0.03, leading to an estimate of the lens mass M=0.50±0.14 M⊙ and its distance to the observer D_L=5.5±0.4 kpc. This is only the second determination of a reasonably precise (<30%) mass estimate for an isolated unseen object, using any method. This allows us to calculate the planetary detection efficiency in physical units (r_perp,m_p), where r_perp is the projected planet-star separation and mp is the planet mass. Results: When computing planet detection efficiency, we did not find any planetary signature, i.e. none of the planetary configurations provides a Δχ2 improvement higher than 60, and our detection efficiency results reveal significant sensitivity to Neptune-mass planets, and to a lesser extent Earth-mass planets in some configurations. Indeed, Jupiter and Neptune-mass planets are excluded with a high confidence for a large projected separation range between the planet and the lens star, respectively [0.6-10] and [1.4-4] AU, and Earth-mass planets are excluded with a 10% confidence in the lensing zone, i.e. [1.8-3.1] AU. Probing Lensing Anomalies NETwork (PLANET). Optical Gravitational Lens Experiment (OGLE). Microlensing Observations in Astrophysics (MOA). Royal Society University research fellow.

  9. Calculation and measurement of 235U and 238U fussion counter assembly detection efficiency

    NASA Astrophysics Data System (ADS)

    Swinhoe, M. T.; Jarvis, O. N.

    1984-04-01

    The detection efficiencies of two fission counter assemblies ( 235U and 238U) designed to measure the neutron flux at JET, have been determined for monoenergetic and radioactive neutron sources. The results are in good agreement with calculations using Monte Carlo neutron transport codes, when care is used in setting up the computer models. The mean difference between calculation and experiment is (7±7%).

  10. New high-efficiency ion-trap mobility detection system for narcotics

    NASA Astrophysics Data System (ADS)

    McGann, William J.

    1997-02-01

    A new patented Ion Trap Mobility Spectrometer design is presented. Conventional IMS designs typically operate below 0.1 percent efficiency. This is due primarily to electric field driven, sample ion discharge on a shutter grid. Since 99.9 percent of the sample ions generated in the reaction region are lost int his discharge process, the sensitivity of conventional systems is limited. The new design provides greater detection efficiency than conventional designs through the use of an 'ion trap' concept. The paper describes the plasma and sample ion dynamics in the reaction region of the new detector and discusses the advantages of utilizing a 'field-free' space to generate sample ions with high efficiency. Fast electronic switching is described which is used to perturb the field-free space and pulse the sample ions into the drift region for separation and subsequent detection using pseudo real-time software for analysis and display of the data. One application for this new detector is now being developed, a portable, hand-held system with switching capability for the detection of drugs and explosives. Preliminary ion spectra and sensitivity data are presented for cocaine and heroin using a hand sniffer configuration.

  11. New, high-efficiency ion trap mobility detection system for narcotics and explosives

    NASA Astrophysics Data System (ADS)

    McGann, William J.; Bradley, V.; Borsody, A.; Lepine, S.

    1994-10-01

    A new patented Ion Trap Mobility Spectrometer (ITMS) design is presented. Conventional IMS designs typically operate below 0.1% efficiency. This is due primarily to electric field driven, sample ion discharge on a shutter grid. Since 99.9% of the sample ions generated in the reaction region are lost in this discharge process, the sensitivity of conventional systems is limited. The new design provides greater detection efficiency than conventional designs through the use of an `ion trap' concept. The paper describes the plasma and sample ion dynamics in the reaction region of the new detector and discusses the advantages of utilizing a `field-free' space to generate sample ions with high efficiency. Fast electronic switching is described which is used to perturb the field-free space and pulse the sample ions into the drift region for separation and subsequent detection using pseudo real-time software for analysis and display of the data. Many applications for this new detector are now being considered including the detection of narcotics and explosives. Preliminary ion spectra, reduced mobility data and sensitivity data are presented for fifteen narcotics, including cocaine, THC and LSD are reported.

  12. New high-efficiency ion trap mobility detection system for narcotics and explosives

    NASA Astrophysics Data System (ADS)

    McGann, William J.; Jenkins, Anthony; Ribiero, K.; Napoli, J.

    1994-03-01

    A new patented ion trap mobility spectrometer design is presented. Conventional IMS designs typically operate below 0.1% efficiency. This is due primarily to electrical-field-driven, sample ion discharge on a shutter grid. Since 99.9% of the sample ions generated in the reaction region are lost in this discharge process, the sensitivity of conventional systems is limited. The new design provides greater detection efficiency than conventional designs through the use of an `ion trap' concept. The paper describes the plasma and sample ion dynamics in the reaction region of the new detector and discusses the advantages of utilizing a `field-free' space to generate sample ions with high efficiency. Fast electronic switching is described which is used to perturb the field-free space and pulse the sample ions into the drift region for separation and subsequent detection using pseudo real-time software for analysis and display of the data. Many applications for this new detector are now being considered including the detection of narcotics and explosives. Preliminary ion spectra, reduced mobility data and sensitivity data are presented for fifteen narcotics, including cocaine, THC, and LSD are reported.

  13. Necessary detection efficiencies for secure quantum key distribution and bound randomness

    NASA Astrophysics Data System (ADS)

    Acín, Antonio; Cavalcanti, Daniel; Passaro, Elsa; Pironio, Stefano; Skrzypczyk, Paul

    2016-01-01

    In recent years, several hacking attacks have broken the security of quantum cryptography implementations by exploiting the presence of losses and the ability of the eavesdropper to tune detection efficiencies. We present a simple attack of this form that applies to any protocol in which the key is constructed from the results of untrusted measurements performed on particles coming from an insecure source or channel. Because of its generality, the attack applies to a large class of protocols, from standard prepare-and-measure to device-independent schemes. Our attack gives bounds on the critical detection efficiencies necessary for secure quantum key distribution, which show that the implementation of most partly device-independent solutions is, from the point of view of detection efficiency, almost as demanding as fully device-independent ones. We also show how our attack implies the existence of a form of bound randomness, namely nonlocal correlations in which a nonsignalling eavesdropper can find out a posteriori the result of any implemented measurement.

  14. Efficient pedestrian detection from aerial vehicles with object proposals and deep convolutional neural networks

    NASA Astrophysics Data System (ADS)

    Minnehan, Breton; Savakis, Andreas

    2016-05-01

    As Unmanned Aerial Systems grow in numbers, pedestrian detection from aerial platforms is becoming a topic of increasing importance. By providing greater contextual information and a reduced potential for occlusion, the aerial vantage point provided by Unmanned Aerial Systems is highly advantageous for many surveillance applications, such as target detection, tracking, and action recognition. However, due to the greater distance between the camera and scene, targets of interest in aerial imagery are generally smaller and have less detail. Deep Convolutional Neural Networks (CNN's) have demonstrated excellent object classification performance and in this paper we adopt them to the problem of pedestrian detection from aerial platforms. We train a CNN with five layers consisting of three convolution-pooling layers and two fully connected layers. We also address the computational inefficiencies of the sliding window method for object detection. In the sliding window configuration, a very large number of candidate patches are generated from each frame, while only a small number of them contain pedestrians. We utilize the Edge Box object proposal generation method to screen candidate patches based on an "objectness" criterion, so that only regions that are likely to contain objects are processed. This method significantly reduces the number of image patches processed by the neural network and makes our classification method very efficient. The resulting two-stage system is a good candidate for real-time implementation onboard modern aerial vehicles. Furthermore, testing on three datasets confirmed that our system offers high detection accuracy for terrestrial pedestrian detection in aerial imagery.

  15. Highly efficient visual detection of trace copper(II) and protein by the quantum photoelectric effect.

    PubMed

    Wang, Peng; Lei, Jianping; Su, Mengqi; Liu, Yueting; Hao, Qing; Ju, Huangxian

    2013-09-17

    This work presented a photocurrent response mechanism of quantum dots (QDs) under illumination with the concept of a quantum photoelectric effect. Upon irradiation, the photoelectron could directly escape from QDs. By using nitro blue tetrazolium (NBT) to capture the photoelectron, a new visual system was proposed due to the formation of an insoluble reduction product, purple formazan, which could be used to visualize the quantum photoelectric effect. The interaction of copper(II) with QDs could form trapping sites to interfere with the quantum confinement and thus blocked the escape of photoelectron, leading to a "signal off" visual method for sensitive copper(II) detection. Meanwhile, by using QDs as a signal tag to label antibody, a "signal on" visual method was also proposed for immunoassay of corresponding protein. With meso-2,3-dimercaptosuccinic-capped CdTe QDs and carcino-embryonic antigen as models, the proposed visual detection methods showed high sensitivity, low detection limit, and wide detectable concentration ranges. The visualization of quantum photoelectric effect could be simply extended for the detection of other targets. This work opens a new visual detection way and provides a highly efficient tool for bioanalysis.

  16. Low background high efficiency radiocesium detection system based on positron emission tomography technology

    SciTech Connect

    Yamamoto, Seiichi; Ogata, Yoshimune

    2013-09-15

    After the 2011 nuclear power plant accident at Fukushima, radiocesium contamination in food became a serious concern in Japan. However, low background and high efficiency radiocesium detectors are expensive and huge, including semiconductor germanium detectors. To solve this problem, we developed a radiocesium detector by employing positron emission tomography (PET) technology. Because {sup 134}Cs emits two gamma photons (795 and 605 keV) within 5 ps, they can selectively be measured with coincidence. Such major environmental gamma photons as {sup 40}K (1.46 MeV) are single photon emitters and a coincidence measurement reduces the detection limit of radiocesium detectors. We arranged eight sets of Bi{sub 4}Ge{sub 3}O{sub 12} (BGO) scintillation detectors in double rings (four for each ring) and measured the coincidence between these detectors using PET data acquisition system. A 50 × 50 × 30 mm BGO was optically coupled to a 2 in. square photomultiplier tube (PMT). By measuring the coincidence, we eliminated most single gamma photons from the energy distribution and only detected those from {sup 134}Cs at an average efficiency of 12%. The minimum detectable concentration of the system for the 100 s acquisition time is less than half of the food monitor requirements in Japan (25 Bq/kg). These results show that the developed radiocesium detector based on PET technology is promising to detect low level radiocesium.

  17. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management.

    PubMed

    Cristescu, Romane H; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams.

  18. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management

    PubMed Central

    Cristescu, Romane H.; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams. PMID:25666691

  19. Accuracy and efficiency of detection dogs: a powerful new tool for koala conservation and management.

    PubMed

    Cristescu, Romane H; Foley, Emily; Markula, Anna; Jackson, Gary; Jones, Darryl; Frère, Céline

    2015-01-01

    Accurate data on presence/absence and spatial distribution for fauna species is key to their conservation. Collecting such data, however, can be time consuming, laborious and costly, in particular for fauna species characterised by low densities, large home ranges, cryptic or elusive behaviour. For such species, including koalas (Phascolarctos cinereus), indicators of species presence can be a useful shortcut: faecal pellets (scats), for instance, are widely used. Scat surveys are not without their difficulties and often contain a high false negative rate. We used experimental and field-based trials to investigate the accuracy and efficiency of the first dog specifically trained for koala scats. The detection dog consistently out-performed human-only teams. Off-leash, the dog detection rate was 100%. The dog was also 19 times more efficient than current scat survey methods and 153% more accurate (the dog found koala scats where the human-only team did not). This clearly demonstrates that the use of detection dogs decreases false negatives and survey time, thus allowing for a significant improvement in the quality and quantity of data collection. Given these unequivocal results, we argue that to improve koala conservation, detection dog surveys for koala scats could in the future replace human-only teams. PMID:25666691

  20. An efficient technique for nuclei segmentation based on ellipse descriptor analysis and improved seed detection algorithm.

    PubMed

    Xu, Hongming; Lu, Cheng; Mandal, Mrinal

    2014-09-01

    In this paper, we propose an efficient method for segmenting cell nuclei in the skin histopathological images. The proposed technique consists of four modules. First, it separates the nuclei regions from the background with an adaptive threshold technique. Next, an elliptical descriptor is used to detect the isolated nuclei with elliptical shapes. This descriptor classifies the nuclei regions based on two ellipticity parameters. Nuclei clumps and nuclei with irregular shapes are then localized by an improved seed detection technique based on voting in the eroded nuclei regions. Finally, undivided nuclei regions are segmented by a marked watershed algorithm. Experimental results on 114 different image patches indicate that the proposed technique provides a superior performance in nuclei detection and segmentation.

  1. The effect of magnetic field on the intrinsic detection efficiency of superconducting single-photon detectors

    SciTech Connect

    Renema, J. J.; Rengelink, R. J.; Komen, I.; Wang, Q.; Kes, P.; Aarts, J.; Exter, M. P. van; Dood, M. J. A. de; Gaudio, R.; Hoog, K. P. M. op 't; Zhou, Z.; Fiore, A.; Sahin, D.; Driessen, E. F. C.

    2015-03-02

    We experimentally investigate the effect of a magnetic field on photon detection in superconducting single-photon detectors (SSPDs). At low fields, the effect of a magnetic field is through the direct modification of the quasiparticle density of states of the superconductor, and magnetic field and bias current are interchangeable, as is expected for homogeneous dirty-limit superconductors. At the field where a first vortex enters the detector, the effect of the magnetic field is reduced, up until the point where the critical current of the detector starts to be determined by flux flow. From this field on, increasing the magnetic field does not alter the detection of photons anymore, whereas it does still change the rate of dark counts. This result points at an intrinsic difference in dark and photon counts, and also shows that no enhancement of the intrinsic detection efficiency of a straight SSPD wire is achievable in a magnetic field.

  2. Serum Multivalent Cationic Pattern: Speculation on the Efficient Approach for Detection of Alzheimer's Disease

    NASA Astrophysics Data System (ADS)

    Azhdarzadeh, Morteza; Noroozian, Maryam; Aghaverdi, Haniyeh; Akbari, Seyed Mostafa; Baum, Larry; Mahmoudi, Morteza

    2013-10-01

    Alzheimer's disease (AD) is increasingly becoming one of the greatest medical challenges. Due to the social and financial burden of AD, detection of AD in its early stages is a topic of major research interest. Thus, emergence of well-validated screening methods for fast detection of AD in the early stages would be of great importance. It is now recognized that the homeostasis and serum bioavailability of multivalent cations (e.g. zinc, copper, and iron) are disturbed in AD. Using a standard chemometric approach (hierarchical clustering analysis), we find that the serum concentrations of an array of such multivalent cations can be a fingerprint for identification of AD patients. This may pave the way for a reliable, efficient, and inexpensive method for early detection and treatment of AD.

  3. Low diversity and low frequency of participation in leisure activities compromise working memory efficiency in young adults.

    PubMed

    Ruiz-Contreras, Alejandra E; Soria-Rodríguez, Gerardo; Almeida-Rosas, Georgina A; García-Vaca, Paola A; Delgado-Herrera, Maribel; Méndez-Díaz, Mónica; Prospéro-García, Oscar

    2012-01-01

    People perform leisure activities (LA) every day; pursuits that entail applying cognitive, physical and social abilities. As in old age, doing LA during early and middle adulthood is related to a reduced risk of dementias, probably by generating a cognitive reserve. As it is possible that a relation between doing LA and working memory (WM) efficiency exists in young adults, we assessed whether the diversity and frequency of LA are related to WM efficiency in this population. Ninety-three healthy young subjects solved the n-back task at two levels of difficulty (2, 3), and answered an LA questionnaire on the activities in which they had participated in the month prior to the experiment. Subjects were classified separately on their scores for (1) diversity (high/low) and (2) frequency (high/low) in order to test the relation between each variable and WM efficiency. Though no differences were found, a subsequent analysis of the average of diversity and frequency ratios of LA performance taken together-the diversity/frequency index-showed that low diversity plus low frequency was significantly associated with reduced WM efficiency at this age; results that suggest that frequent participation in diverse LA during youth is related to WM efficiency.

  4. Early and Efficient Detection of Mycobacterium tuberculosis in Sputum by Microscopic Observation of Broth Cultures

    PubMed Central

    Kidenya, Benson R.; Kabangila, Rodrick; Peck, Robert N.; Mshana, Stephen E.; Webster, Lauren E.; Koenig, Serena P.; Johnson, Warren D.; Fitzgerald, Daniel W.

    2013-01-01

    Early, efficient and inexpensive methods for the detection of pulmonary tuberculosis are urgently needed for effective patient management as well as to interrupt transmission. These methods to detect M. tuberculosis in a timely and affordable way are not yet widely available in resource-limited settings. In a developing-country setting, we prospectively evaluated two methods for culturing and detecting M. tuberculosis in sputum. Sputum samples were cultured in liquid assay (micro broth culture) in microplate wells and growth was detected by microscopic observation, or in Löwenstein–Jensen (LJ) solid media where growth was detected by visual inspection for colonies. Sputum samples were collected from 321 tuberculosis (TB) suspects attending Bugando Medical Centre, in Mwanza, Tanzania, and were cultured in parallel. Pulmonary tuberculosis cases were diagnosed using the American Thoracic Society diagnostic standards. There were a total of 200 (62.3%) pulmonary tuberculosis cases. Liquid assay with microscopic detection detected a significantly higher proportion of cases than LJ solid culture: 89.0% (95% confidence interval [CI], 84.7% to 93.3%) versus 77.0% (95% CI, 71.2% to 82.8%) (p = 0.0007). The median turn around time to diagnose tuberculosis was significantly shorter for micro broth culture than for the LJ solid culture, 9 days (interquartile range [IQR] 7–13), versus 21 days (IQR 14–28) (p<0.0001). The cost for micro broth culture (labor inclusive) in our study was US $4.56 per sample, versus US $11.35 per sample for the LJ solid culture. The liquid assay (micro broth culture) is an early, feasible, and inexpensive method for detection of pulmonary tuberculosis in resource limited settings. PMID:23469014

  5. [Detection and Serotyping of Streptococcus pneumoniae Carried in Healthy Adults with a Modified PCR Method].

    PubMed

    Ishihara, Yuka; Okamoto, Akira; Ohta, Michio

    2015-05-01

    Detection of Streptococcus pneumoniae colonized in the pharynx of healthy carriers currently relies on conventional culture methods of direct plating with pharyngeal swab specimens. The accurate measurement of the carriage of pneumococci, however, has not been necessarily achieved with these methods due to low density colonization and contamination of numerous oral streptococci that express α-hemolysis. A PCR-based detection method of pneumococci-specific for lytA as well as PCR serotyping of S. pneumoniae was recently developed and their effectiveness was confirmed. We modified the reaction conditions of these methods to improve the detection rate and applied them to the measurement of S. pneumoniae carried in healthy adults. Pharyngeal swab specimens obtained from 110 healthy volunteers over 40 and living in Nagoya were enriched for 5 hours with broth medium supplemented with rabbit serum and the template DNA for PCR was extracted from the mixed enriched culture. Of 110 specimens 36 (32.7%) were lytA-positive, the rate of which was much higher than the results of previous culture-based studies. The DNA template preparations were then used for PCR-based serotyping with primers specific for each of the types included in pneumococcal 23 valent vaccine (PPV23). We found that 28 out of 36 lytA-positive carriers were identified as being positive for the serotypes belonging to PPV23, although serotypes 6A and 6B were indistinguishable with the PCR method. The most frequent serotype was serotype 14, and serotypes 4, 18C, and 6A/B were also frequently identified. Five lytA-positive carriers were previously vaccinated with PPV23, and among them, 4 were positive for serotypes contained in PPV23. We recommend PCR-based identification and serotyping of S. pneumoniae in broth enrichment culture of pharyngeal swab specimens as a reliable method for the surveillance of healthy carriers with low density colonization. PMID:26552129

  6. The efficiency of concentration methods used to detect enteric viruses in anaerobically digested sludge

    PubMed Central

    Prado, Tatiana; Guilayn, Wilma de Carvalho Pereira Bonet; Gaspar, Ana Maria Coimbra; Miagostovich, Marize Pereira

    2013-01-01

    The presence of enteric viruses in biosolids can be underestimated due to the inefficient methods (mainly molecular methods) used to recover the viruses from these matrices. Therefore, the goal of this study was to evaluate the different methods used to recover adenoviruses (AdV), rotavirus species A (RVA), norovirus genogroup II (NoV GII) and the hepatitis A virus (HAV) from biosolid samples at a large urban wastewater treatment plant in Brazil after they had been treated by mesophilic anaerobic digestion. Quantitative polymerase chain reaction (PCR) was used for spiking experiments to compare the detection limits of feasible methods, such as beef extract elution and ultracentrifugation. Tests were performed to detect the inhibition levels and the bacteriophage PP7 was used as an internal control. The results showed that the inhibitors affected the efficiency of the PCR reaction and that beef extract elution is a suitable method for detecting enteric viruses, mainly AdV from biosolid samples. All of the viral groups were detected in the biosolid samples: AdV (90%), RVA, NoV GII (45%) and HAV (18%), indicating the viruses' resistance to the anaerobic treatment process. This is the first study in Brazil to detect the presence of RVA, AdV, NoV GII and HAV in anaerobically digested sludge, highlighting the importance of adequate waste management. PMID:23440119

  7. ELENA MCP detector: absolute detection efficiency for low-energy neutral atoms

    NASA Astrophysics Data System (ADS)

    Rispoli, R.; De Angelis, E.; Colasanti, L.; Vertolli, N.; Orsini, S.; Scheer, J. A.; Mura, A.; Milillo, A.; Wurz, P.; Selci, S.; Di Lellis, A. M.; Leoni, R.; D'Alessandro, M.; Mattioli, F.; Cibella, S.

    2012-09-01

    Microchannel Plates (MCP) detectors are frequently used in space instrumentation for detecting a wide range of radiation and particles. In particular, the capability to detect non-thermal low energy neutral species is crucial for the sensor ELENA (Emitted Low-Energy Neutral Atoms), part of the package SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) on board the BepiColombo mission of ESA to Mercury to be launched in 2015. ELENA is a Time of Flight (TOF) sensor, based on a novel concept using an ultra-sonic oscillating shutter (Start section), which is operated at frequencies up to 50 kHz; a MCP detector is used as a Stop detector. The scientific objective of ELENA is to detect energetic neutral atoms in the range 10 eV - 5 keV, within 76° FOV, perpendicular to the S/C orbital plane. ELENA will monitor the emission of neutral atoms from the whole surface of Mercury thanks to the spacecraft motion. The major scientific objectives are the interaction between the plasma environment and the planet’s surface, the global particle loss-rate and the remote sensing of the surface properties. In particular, surface release processes are investigated by identifying particles released from the surface, via solar wind-induced ion sputtering (< 1eV - < 100 eV) as well as Hydrogen back-scattered at hundreds eV. MCP absolute detection efficiency for very low energy neutral atoms (E < 30 eV) is a crucial point for this investigation. At the MEFISTO facility of the Physical Institute of the University of Bern (CH), measurements on three different types of MCP (with and without coating) have been performed providing the detection efficiencies in the energy range 10eV - 1keV. Outcomes from such measurements are discussed here.

  8. More than Just Another Face in the Crowd: Superior Detection of Threatening Facial Expressions in Children and Adults

    ERIC Educational Resources Information Center

    LoBue, Vanessa

    2009-01-01

    Threatening facial expressions can signal the approach of someone or something potentially dangerous. Past research has established that adults have an attentional bias for angry faces, visually detecting their presence more quickly than happy or neutral faces. Two new findings are reported here. First, evidence is presented that young children…

  9. A robust and efficient approach to detect 3D rectal tubes from CT colonography

    SciTech Connect

    Yang Xiaoyun; Slabaugh, Greg

    2011-11-15

    Purpose: The rectal tube (RT) is a common source of false positives (FPs) in computer-aided detection (CAD) systems for CT colonography. A robust and efficient detection of RT can improve CAD performance by eliminating such ''obvious'' FPs and increase radiologists' confidence in CAD. Methods: In this paper, we present a novel and robust bottom-up approach to detect the RT. Probabilistic models, trained using kernel density estimation on simple low-level features, are employed to rank and select the most likely RT tube candidate on each axial slice. Then, a shape model, robustly estimated using random sample consensus (RANSAC), infers the global RT path from the selected local detections. Subimages around the RT path are projected into a subspace formed from training subimages of the RT. A quadratic discriminant analysis (QDA) provides a classification of a subimage as RT or non-RT based on the projection. Finally, a bottom-top clustering method is proposed to merge the classification predictions together to locate the tip position of the RT. Results: Our method is validated using a diverse database, including data from five hospitals. On a testing data with 21 patients (42 volumes), 99.5% of annotated RT paths have been successfully detected. Evaluated with CAD, 98.4% of FPs caused by the RT have been detected and removed without any loss of sensitivity. Conclusions: The proposed method demonstrates a high detection rate of the RT path, and when tested in a CAD system, reduces FPs caused by the RT without the loss of sensitivity.

  10. The efficiency of vaginal temperature measurement for detection of estrus in Japanese Black cows

    PubMed Central

    SAKATANI, Miki; TAKAHASHI, Masashi; TAKENOUCHI, Naoki

    2016-01-01

    Recently, weak estrous behavior was assumed to be the cause of a decline in breeding efficiency in cattle. The present study investigated the effect of measuring the vaginal temperature on the detection of estrus in Japanese Black cows. First, the effect of hormone administration to cows with a functional corpus luteum on the vaginal temperature was evaluated by continuous measurement using a temperature data logger. After 24 h of cloprostenol (PG) treatment, the vaginal temperature was significantly lower than on day 7 after estrus, and the low values were maintained until the beginning of estrus (P < 0.05). The cows that received PG and exogenous progesterone (CIDR) did not show a temperature decrease until the CIDR was removed. This finding suggested that the vaginal temperature change reflected the progesterone concentration. The rate of detection of natural estrus was lower for a pedometer than for the vaginal temperature (P < 0.05); synchronization of estrus resulted in a high estrus detection rate regardless of the detection method. In a subsequent experiment, the effect of vaginal temperature measurement and the use of a pedometer on estrus detection was evaluated in the cool and hot seasons. The average activities during non-estrus and the activity increase ratio (estrus/non-estrus) changed according to season (P < 0.01, P < 0.05). However, the average vaginal temperatures during estrus and non-estrus were not affected by season. The estrus detection rate of the pedometer was lower in summer and lower than that obtained using the vaginal temperature. These results indicated that vaginal temperature measurement might be effective for detecting estrus regardless of estrous behavior. PMID:26853785

  11. Entropy Beacon: A Hairpin-Free DNA Amplification Strategy for Efficient Detection of Nucleic Acids.

    PubMed

    Lv, Yifan; Cui, Liang; Peng, Ruizi; Zhao, Zilong; Qiu, Liping; Chen, Huapei; Jin, Cheng; Zhang, Xiao-Bing; Tan, Weihong

    2015-12-01

    Here, we propose an efficient strategy for enzyme- and hairpin-free nucleic acid detection called an entropy beacon (abbreviated as Ebeacon). Different from previously reported DNA hybridization/displacement-based strategies, Ebeacon is driven forward by increases in the entropy of the system, instead of free energy released from new base-pair formation. Ebeacon shows high sensitivity, with a detection limit of 5 pM target DNA in buffer and 50 pM in cellular homogenate. Ebeacon also benefits from the hairpin-free amplification strategy and zero-background, excellent thermostability from 20 °C to 50 °C, as well as good resistance to complex environments. In particular, based on the huge difference between the breathing rate of a single base pair and two adjacent base pairs, Ebeacon also shows high selectivity toward base mutations, such as substitution, insertion, and deletion and, therefore, is an efficient nucleic acid detection method, comparable to most reported enzyme-free strategies.

  12. Efficient edge-guided full-waveform inversion by Canny edge detection and bilateral filtering algorithms

    NASA Astrophysics Data System (ADS)

    Xiang, Shiming; Zhang, Haijiang

    2016-11-01

    It is known full-waveform inversion (FWI) is generally ill-conditioned and various strategies including pre-conditioning and regularizing the inversion system have been proposed to obtain a reliable estimation of the velocity model. Here, we propose a new edge-guided strategy for FWI in frequency domain to efficiently and reliably estimate velocity models with structures of the size similar to the seismic wavelength. The edges of the velocity model at the current iteration are first detected by the Canny edge detection algorithm that is widely used in image processing. Then, the detected edges are used for guiding the calculation of FWI gradient as well as enforcing edge-preserving total variation (TV) regularization for next iteration of FWI. Bilateral filtering is further applied to remove noise but keep edges of the FWI gradient. The proposed edge-guided FWI in the frequency domain with edge-guided TV regularization and bilateral filtering is designed to preserve model edges that are recovered from previous iterations as well as from lower frequency waveforms when FWI is conducted from lower to higher frequencies. The new FWI method is validated using the complex Marmousi model that contains several steeply dipping fault zones and hundreds of horizons. Compared to FWI without edge guidance, our proposed edge-guided FWI recovers velocity model anomalies and edges much better. Unlike previous image-guided FWI or edge-guided TV regularization strategies, our method does not require migrating seismic data, thus is more efficient for real applications.

  13. CK-LPA: Efficient community detection algorithm based on label propagation with community kernel

    NASA Astrophysics Data System (ADS)

    Lin, Zhen; Zheng, Xiaolin; Xin, Nan; Chen, Deren

    2014-12-01

    With the rapid development of Web 2.0 and the rise of online social networks, finding community structures from user data has become a hot topic in network analysis. Although research achievements are numerous at present, most of these achievements cannot be adopted in large-scale social networks because of heavy computation. Previous studies have shown that label propagation is an efficient means to detect communities in social networks and is easy to implement; however, some drawbacks, such as low accuracy, high randomness, and the formation of a “monster” community, have been found. In this study, we propose an efficient community detection method based on the label propagation algorithm (LPA) with community kernel (CK-LPA). We assign a corresponding weight to each node according to node importance in the whole network and update node labels in sequence based on weight. Then, we discuss the composition of weights, the label updating strategy, the label propagation strategy, and the convergence conditions. Compared with the primitive LPA, existing drawbacks are solved by CK-LPA. Experiments and benchmarks reveal that our proposed method sustains nearly linear time complexity and exhibits significant improvements in the quality aspect of static community detection. Hence, the algorithm can be applied in large-scale social networks.

  14. Quantitative Molecular Detection of 19 Major Pathogens in the Interdental Biofilm of Periodontally Healthy Young Adults

    PubMed Central

    Carrouel, Florence; Viennot, Stéphane; Santamaria, Julie; Veber, Philippe; Bourgeois, Denis

    2016-01-01

    pathogen in adult periodontal disease, represents 8.08% of the 19 bacteria analyzed. P. gingivalis was detected in 19% of healthy subjects and represents 0.02% of the interdental biofilm. T. forsythensis and T. denticola (0.02 and 0.04% of the interdental biofilm) were detected in 93 and 49% of healthy subjects, respectively. The effective presence of periodontal pathogens is a strong indicator of the need to develop new methods for disrupting interdental biofilm in daily oral hygiene. PMID:27313576

  15. Quantitative Molecular Detection of 19 Major Pathogens in the Interdental Biofilm of Periodontally Healthy Young Adults.

    PubMed

    Carrouel, Florence; Viennot, Stéphane; Santamaria, Julie; Veber, Philippe; Bourgeois, Denis

    2016-01-01

    pathogen in adult periodontal disease, represents 8.08% of the 19 bacteria analyzed. P. gingivalis was detected in 19% of healthy subjects and represents 0.02% of the interdental biofilm. T. forsythensis and T. denticola (0.02 and 0.04% of the interdental biofilm) were detected in 93 and 49% of healthy subjects, respectively. The effective presence of periodontal pathogens is a strong indicator of the need to develop new methods for disrupting interdental biofilm in daily oral hygiene. PMID:27313576

  16. Gait energetic efficiency in older adults with and without knee pain: results from the Baltimore Longitudinal Study of Aging.

    PubMed

    Ko, Seung-Uk; Simonsick, Eleanor M; Ferrucci, Luigi

    2015-02-01

    With aging, customary gait patterns change and energetic efficiency declines, but the relationship between these alterations is not well understood. If gait characteristics that develop with aging explain part of the decline in energetic efficiency that occur in most aging individuals, then efforts to modify these characteristics could delay or prevent mobility limitation. This study characterizes gait patterns in older persons with and without knee pain and tests the hypothesis that changes in gait characteristics due to knee pain are associated with increased energetic cost of walking in older adults. Study participants were 364 men and 170 women aged 60 to 96 years enrolled in the Baltimore Longitudinal Study of Aging (BLSA), of whom 86 had prevalent knee pain. Gait patterns were assessed at participant self-selected usual pace in the gait laboratory, and the energetic cost of walking was assessed by indirect calorimetry during self-selected usual pace walking over 2.5 min in a tiled corridor using a portable equipment. Participants with knee pain were less energetically efficient than those without pain (oxygen consumption 0.97 vs. 0.88 ml/(10 m · 100 kg); p = 0.002) and had slower gait speed and smaller range of motion (ROM) at the hip and knee joints (p < 0.05, for all). Slower gait speed and lower knee ROM in participants with knee pain and longer double support time and higher ankle ROM in participants without knee pain were associated with lower energetic efficiency (p < 0.05, for all). Slower gait speed and lower knee ROM were correlates of knee pain and were found to mediate the association between age and oxygen consumption. Although knee pain is associated with a higher energetic cost of walking, gait characteristics associated with energetic efficiency differ by pain status which suggests that compensatory strategies both in the presence and absence of pain may impact gait efficiency.

  17. Signal Processing and Its Effect on Scanning Efficiencies for a Field Instrument for Detecting Low-energy Radiation.

    PubMed

    Marianno, Craig M

    2015-07-01

    Signal processing within a radiation detector affects detection efficiency. Currently, organizations such as private industry, the U.S. Navy, Army, and Air Force are coupling some detector systems with data collection devices to survey large land areas for radioactive contamination. As detector technology has advanced and analog data collection has turned to digital, signal processing is becoming prevalent in some instruments. Using a NIST traceable (241)Am source, detection efficiency for a field instrument for detecting low-energy radiation (FIDLER) was examined for both a static and scanning mode. Experimental results were compared to Monte Carlo-generated efficiencies. Stationary data compared nicely to the theoretical results. Conversely, scanning detection efficiencies were considerably different from their theoretical counterparts. As speed increased, differences in detection efficiency approached two orders of magnitude. To account for these differences, a quasi time-dependent Monte Carlo simulation was created mimicking the signal processing undertaken by the FIDLER detection system. By including signal processing, experimental results fell within the bounds of the Monte Carlo-generated efficiencies, thus demonstrating the negative effects of such processing on detection efficiencies. PMID:26011500

  18. Signal Processing and Its Effect on Scanning Efficiencies for a Field Instrument for Detecting Low-energy Radiation.

    PubMed

    Marianno, Craig M

    2015-07-01

    Signal processing within a radiation detector affects detection efficiency. Currently, organizations such as private industry, the U.S. Navy, Army, and Air Force are coupling some detector systems with data collection devices to survey large land areas for radioactive contamination. As detector technology has advanced and analog data collection has turned to digital, signal processing is becoming prevalent in some instruments. Using a NIST traceable (241)Am source, detection efficiency for a field instrument for detecting low-energy radiation (FIDLER) was examined for both a static and scanning mode. Experimental results were compared to Monte Carlo-generated efficiencies. Stationary data compared nicely to the theoretical results. Conversely, scanning detection efficiencies were considerably different from their theoretical counterparts. As speed increased, differences in detection efficiency approached two orders of magnitude. To account for these differences, a quasi time-dependent Monte Carlo simulation was created mimicking the signal processing undertaken by the FIDLER detection system. By including signal processing, experimental results fell within the bounds of the Monte Carlo-generated efficiencies, thus demonstrating the negative effects of such processing on detection efficiencies.

  19. Measurements of the photon detection efficiency done for Geiger-mode avalanche photodiodes (G-APD)

    NASA Astrophysics Data System (ADS)

    Gentile, S.; Meddi, F.; Kuznetsova, E.

    2010-04-01

    Estimation of the Photon Detect Efficiency (PDE) of multi-pixel Geiger-mode avalanche photodiodes (G-APD) based on measurements of the G-APD response to low-intensity light is presented. The fit of the light-response spectra takes into account after-pulsing and cross-talk effects and yields the value of initial photons. Using a calibrated photo-detector as a reference, the value of the PDE can be calculated. The sources of systematic error of the obtained PDE is discussed as well as possibility for its minimization.

  20. An efficient moving target detection algorithm based on sparsity-aware spectrum estimation.

    PubMed

    Shen, Mingwei; Wang, Jie; Wu, Di; Zhu, Daiyin

    2014-09-12

    In this paper, an efficient direct data domain space-time adaptive processing (STAP) algorithm for moving targets detection is proposed, which is achieved based on the distinct spectrum features of clutter and target signals in the angle-Doppler domain. To reduce the computational complexity, the high-resolution angle-Doppler spectrum is obtained by finding the sparsest coefficients in the angle domain using the reduced-dimension data within each Doppler bin. Moreover, we will then present a knowledge-aided block-size detection algorithm that can discriminate between the moving targets and the clutter based on the extracted spectrum features. The feasibility and effectiveness of the proposed method are validated through both numerical simulations and raw data processing results.

  1. An efficient moving target detection algorithm based on sparsity-aware spectrum estimation.

    PubMed

    Shen, Mingwei; Wang, Jie; Wu, Di; Zhu, Daiyin

    2014-01-01

    In this paper, an efficient direct data domain space-time adaptive processing (STAP) algorithm for moving targets detection is proposed, which is achieved based on the distinct spectrum features of clutter and target signals in the angle-Doppler domain. To reduce the computational complexity, the high-resolution angle-Doppler spectrum is obtained by finding the sparsest coefficients in the angle domain using the reduced-dimension data within each Doppler bin. Moreover, we will then present a knowledge-aided block-size detection algorithm that can discriminate between the moving targets and the clutter based on the extracted spectrum features. The feasibility and effectiveness of the proposed method are validated through both numerical simulations and raw data processing results. PMID:25222035

  2. Efficient signal processing for time-resolved fluorescence detection of nitrogen-vacancy spins in diamond

    NASA Astrophysics Data System (ADS)

    Gupta, A.; Hacquebard, L.; Childress, L.

    2016-03-01

    Room-temperature fluorescence detection of the nitrogen-vacancy center electronic spin typically has low signal to noise, requiring long experiments to reveal an averaged signal. Here, we present a simple approach to analysis of time-resolved fluorescence data that permits an improvement in measurement precision through signal processing alone. Applying our technique to experimental data reveals an improvement in signal to noise equivalent to a 14% increase in photon collection efficiency. We further explore the dependence of the signal to noise ratio on excitation power, and analyze our results using a rate equation model. Our results provide a rubric for optimizing fluorescence spin detection, which has direct implications for improving precision of nitrogen-vacancy-based sensors.

  3. Accounting for Limited Detection Efficiency and Localization Precision in Cluster Analysis in Single Molecule Localization Microscopy

    PubMed Central

    Shivanandan, Arun; Unnikrishnan, Jayakrishnan; Radenovic, Aleksandra

    2015-01-01

    Single Molecule Localization Microscopy techniques like PhotoActivated Localization Microscopy, with their sub-diffraction limit spatial resolution, have been popularly used to characterize the spatial organization of membrane proteins, by means of quantitative cluster analysis. However, such quantitative studies remain challenged by the techniques’ inherent sources of errors such as a limited detection efficiency of less than 60%, due to incomplete photo-conversion, and a limited localization precision in the range of 10 – 30nm, varying across the detected molecules, mainly depending on the number of photons collected from each. We provide analytical methods to estimate the effect of these errors in cluster analysis and to correct for them. These methods, based on the Ripley’s L(r) – r or Pair Correlation Function popularly used by the community, can facilitate potentially breakthrough results in quantitative biology by providing a more accurate and precise quantification of protein spatial organization. PMID:25794150

  4. Occasional detection of thymic epithelial tumor 4 years after diagnosis of adult onset Still disease

    PubMed Central

    Lococo, Filippo; Bajocchi, Gianluigi; Caruso, Andrea; Valli, Riccardo; Ricchetti, Tommaso; Sgarbi, Giorgio; Salvarani, Carlo

    2016-01-01

    Abstract Background: Thymoma is a T cell neoplasm arising from the thymic epithelium that due to its immunological role, frequently undercover derangements of immunity such a tumors and autoimmune diseases. Methods: Herein, we report, to the best of our knowledge, the first description of an association between thymoma and adult onset Still disease (AOSD) in a 47-year-old man. The first one was occasionally detected 4 years later the diagnosis of AOSD, and surgically removed via right lateral thoracotomy. Histology confirmed an encapsulated thymic tumor (type AB sec. WHO-classification). Results: The AOSD was particularly resistant to the therapy, requiring a combination of immunosuppressant followed by anti-IL1R, that was the only steroids-sparing treatment capable to induce and maintain the remission. The differential diagnosis was particularly challenging because of the severe myasthenic-like symptoms that, with normal laboratory tests, were initially misinterpreted as fibromyalgia. The pathogenic link of this association could be a thymus escape of autoreactive T lymphocytes causing autoimmunity. Conclusion: Clinicians should be always include the possibility of a thymoma in the differential diagnosis of an unusual new onset of weakness and normal laboratories data, in particular once autoimmune disease is present in the medical history. PMID:27603335

  5. [Early detection of chronic liver disease in primary care in the apparently health adult population].

    PubMed

    Caballería, Llorenç; Torán, Pere

    2012-12-01

    Liver diseases are highly prevalent and are a major health problem as they progress to more severe forms. In the west, cirrhosis and primitive liver cancer are among the first 10 causes of death in adults. Moreover, chronic liver inflammation, irrespective of cause, is usually asymptomatic. Consequently diagnosis tends to be established when the disease is in the advanced stages and is thus irreversible and with few treatment possibilities. Therefore, ideally, diagnosis would be established in the initial phases of chronic liver inflammation, which would allow the natural history of the disease to be altered by either halting or delaying progression. To date, physicians have been guided by alterations in liver function tests to identify the etiology of liver disease or-depending on the severity of involvement-the presence of liver disease. Abdominal ultrasound findings can also reveal alterations suggesting the presence of chronic liver disease. However, in the last few years, noninvasive methods have been designed. These include serological markers (direct and indirect) of fibrosis and radiological tests (especially elastography) based on measuring liver elasticity, which allow noninvasive quantification of the degree of fibrous tissue in the liver. The use of noninvasive methods may be highly useful in the early detection of liver diseases.

  6. Adult male circumcision in Nyanza, Kenya at scale: the cost and efficiency of alternative service delivery modes

    PubMed Central

    2014-01-01

    Background Adult male circumcision (MC) services in Kenya are provided through both horizontal and vertical programs, and via facility-based, mobile and outreach service delivery. This study assesses the costs and composition of unit costs for each program approach and service delivery mode and assess the cost-effectiveness of each. Methods This study was conducted on the unit costs of adult MC delivery in 222 purposively-selected MC delivery sites in Nyanza Province, Kenya from November 2008 through April 2010 using program data from the AIDS, Population, and Health Integrated Assistance Project II (APHIA II) and from the Nyanza Reproductive Health Society (NRHS). The former program can be characterized as horizontal or integrated; the latter as ‘diagonal’; containing both horizontal and vertical elements. Expenditure and services data were collected from project financial and monitoring documents and via discussions with program officials. In addition, per-case, direct service delivery costs were calculated using time and motion observations of 246 adult MC procedures performed during May and June, 2010. We calculated the cost per HIV infections averted for each of the service delivery modalities. Results Unit cost per adult MC was $38.62 and $44.24 for APHIA II and NRHS respectively, ranging from $29.32 (APHIA II mobile) to $46.20 (NRHS outreach/mobile). Unit costs at base facilities was similar for the two approaches. Time and motion data revealed that the opportunity cost of the elapsed time between the arrival of the surgical team and the time the first MC procedure begins varies between $2.08 and $6.27 per case. The cost per HIV infection (HIA) averted ranged from $117.29 for mobile service via the horizontal APHIA-II program to $184.84 per HIA for the diagonal NRHS program. Conclusions This study provides evidence for the similar efficiency of a horizontal approach (APHIA II) and a combination of horizontal and vertical approaches (NRHS) to support

  7. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XVI; Alternative Designs for Future Adult PIT-Tag Detection Studies, 2000 Technical Report.

    SciTech Connect

    Perez-Comas, Jose A.; Skalski, John R.

    2000-09-25

    In the advent of the installation of a PIT-tag interrogation system in the Cascades Island fish ladder at Bonneville Dam (BON), and other CRB dams, this overview describes in general terms what can and cannot be estimated under seven different scenarios of adult PIT-tag detection capabilities in the CRB. Moreover, this overview attempted to identify minimal adult PIT-tag detection configurations required by the ten threatened Columbia River Basin (CRB) chinook and steelhead ESUs. A minimal adult PIT-tag detection configuration will require the installation of adult PIT-tag detection facilities at Bonneville Dam and another dam above BON. Thus, the Snake River spring/summer and fall chinook salmon, and the Snake River steelhead will require a minimum of three dams with adult PIT-tag detection capabilities to guarantee estimates of ''ocean survival'' and at least of one independent, in-river returning adult survival (e.g., adult PIT-tag detection facilities at BON and LGR dams and at any other intermediary dam such as IHR). The Upper Columbia River spring chinook salmon and steelhead will also require a minimum of three dams with adult PIT-tag detection capabilities: BON and two other dams on the BON-WEL reach. The current CRB dam system configuration and BPA's and COE's commitment to install adult PIT-tag detectors only in major CRB projects will not allow the estimation of an ''ocean survival'' and of any in-river adult survival for the Lower Columbia River chinook salmon and steelhead. The Middle Columbia River steelhead ESU will require a minimum of two dams with adult PIT-tag detection capabilities: BON and another upstream dam on the BON-McN reach. Finally, in spite of their importance in terms of releases, PIT-tag survival studies for the Upper Willamette chinook and Upper Willamette steelhead ESUs cannot be perform with the current CRB dam system configuration and PIT-tag detection capabilities.

  8. An Energy-Efficient Cluster-Based Vehicle Detection on Road Network Using Intention Numeration Method

    PubMed Central

    Devasenapathy, Deepa; Kannan, Kathiravan

    2015-01-01

    The traffic in the road network is progressively increasing at a greater extent. Good knowledge of network traffic can minimize congestions using information pertaining to road network obtained with the aid of communal callers, pavement detectors, and so on. Using these methods, low featured information is generated with respect to the user in the road network. Although the existing schemes obtain urban traffic information, they fail to calculate the energy drain rate of nodes and to locate equilibrium between the overhead and quality of the routing protocol that renders a great challenge. Thus, an energy-efficient cluster-based vehicle detection in road network using the intention numeration method (CVDRN-IN) is developed. Initially, sensor nodes that detect a vehicle are grouped into separate clusters. Further, we approximate the strength of the node drain rate for a cluster using polynomial regression function. In addition, the total node energy is estimated by taking the integral over the area. Finally, enhanced data aggregation is performed to reduce the amount of data transmission using digital signature tree. The experimental performance is evaluated with Dodgers loop sensor data set from UCI repository and the performance evaluation outperforms existing work on energy consumption, clustering efficiency, and node drain rate. PMID:25793221

  9. Assessment of objective image quality in digital radiography: noninvasive determination of the detective quantum efficiency

    NASA Astrophysics Data System (ADS)

    Kamm, Karl-Friedrich; Steiner, Reinhard; Tilkorn, Karl

    1996-04-01

    In order to determine an objective measure of a system's image quality, we developed a simple, non-invasive measurement procedure to determine the detective quantum efficiency of digital radiographic systems, especially image intensifier-tv systems. Therefore we set up measurement procedures for the quantities intensity transfer function (ITF) (also called characteristic curve), modulation transfer function (MTF), noise power spectrum (NPS) and the low frequency drop (LFD). The quantities ITF, MTF, NPS and LFD are determined by the analysis of images of simple, standardized test objects (a slit, Al-filters of different thickness and a lead disk). The images are automatically evaluated by means of an Apple Macintosh workstation and the program NIH image with some special extensions. The resulting quantities MTF, NPS, LFD are combined to determine the noise equivalent quanta (NEQ) and the detective quantum efficiency (DQE). By means of this measurement procedure quantities, that describe the objective image quality like NEQ and DQE, can be determined in a simple way. Only a set of 45 images is needed for diagnosis of a system. This method provides a powerful analysis tool for image quality, that is applicable in the field and can be done from a remote location. It may be used in a clinical environment (e.g. in constancy testing).

  10. PSA discriminator influence on (222)Rn efficiency detection in waters by liquid scintillation counting.

    PubMed

    Stojković, Ivana; Todorović, Nataša; Nikolov, Jovana; Tenjović, Branislava

    2016-06-01

    A procedure for the (222)Rn determination in aqueous samples using liquid scintillation counting (LSC) was evaluated and optimized. Measurements were performed by ultra-low background spectrometer Quantulus 1220™ equipped with PSA (Pulse Shape Analysis) circuit which discriminates alpha/beta spectra. Since calibration procedure is carried out with (226)Ra standard, which has both alpha and beta progenies, it is clear that PSA discriminator has vital importance in order to provide precise spectra separation. Improvement of calibration procedure was done through investigation of PSA discriminator level and, consequentially, the activity of (226)Ra calibration standard influence on (222)Rn efficiency detection. Quench effects on generated spectra i.e. determination of radon efficiency detection were also investigated with quench calibration curve obtained. Radon determination in waters based on modified procedure according to the activity of (226)Ra standard used, dependent on PSA setup, was evaluated with prepared (226)Ra solution samples and drinking water samples with assessment of measurement uncertainty variation included. PMID:27016710

  11. Efficient detection of a CW signal with a linear frequency drift

    NASA Technical Reports Server (NTRS)

    Swarztrauber, Paul N.; Bailey, David H.

    1989-01-01

    An efficient method is presented for the detection of a continuous wave (CW) signal with a frequency drift that is linear in time. Signals of this type occur in transmissions between any two locations that are accelerating relative to one another, e.g., transmissions from the Voyager spacecraft. We assume that both the frequency and the drift are unknown. We also assume that the signal is weak compared to the Gaussian noise. The signal is partitioned into subsequences whose discrete Fourier transforms provide a sequence of instantaneous spectra at equal time intervals. These spectra are then accumulated with a shift that is proportional to time. When the shift is equal to the frequency drift, the signal to noise ratio increases and detection occurs. Here, we show how to compute these accumulations for many shifts in an efficient manner using a variety of Fast Fourier Transformations (FFT). Computing time is proportional to L log L where L is the length of the time series.

  12. Effects of early cold adaptation on food efficiency and dietary-induced thermogenesis in the adult rat.

    PubMed

    Davis, J R; Tagliaferro, A R; Roberts, J S; Hill, J O

    1982-07-01

    The food intakes of male and female rats (Harvard strain) adapted to cold (5 degrees C) starting at weaning were studied in the cold and during reacclimation to 25 degrees C. Following 24 hr food deprivation, the male rats regained the weight they had lost without making up for the food they had missed (increased food efficiency), while the female rats ate 75% more food than they had missed in regaining their body weights (decreased food efficiency), independent of the temperature at which the animals were housed. On a high fat diet, both cold groups gained less weight than did the two control groups. However, each female group gained significantly less weight than its same temperature male group. Dietary-induced thermogenesis was significantly enhanced in male cold adapted rats 3 months after reacclimation to the zone of thermal neutrality but not in cold adapted female rats. Sex and strain differences are discussed. These data indicate that early chronic cold exposure results in both immediate and long-term changes in food efficiency and metabolism in adult rats, but the effects vary with the sex of the animal.

  13. Effect of the wire width on the intrinsic detection efficiency of superconducting-nanowire single-photon detectors

    SciTech Connect

    Lusche, R. Semenov, A.; Ilin, K.; Siegel, M.; Korneeva, Y.; Trifonov, A.; Korneev, A.; Goltsman, G.; Vodolazov, D.; Hübers, H.-W.

    2014-07-28

    A thorough spectral study of the intrinsic single-photon detection efficiency in superconducting TaN and NbN nanowires with different widths has been performed. The experiment shows that the cut-off of the intrinsic detection efficiency at near-infrared wavelengths is most likely controlled by the local suppression of the barrier for vortex nucleation around the absorption site. Beyond the cut-off quasi-particle diffusion in combination with spontaneous, thermally activated vortex crossing explains the detection process. For both materials, the reciprocal cut-off wavelength scales linearly with the wire width where the scaling factor agrees with the hot-spot detection model.

  14. An efficient contextual algorithm to detect subsurface fires with NOAA/AVHRR data

    SciTech Connect

    Gautam, R.S.; Singh, D.; Mittal, A.

    2008-07-15

    This paper deals with the potential application of National Oceanic and Atmospheric Administration (NOAA)/Advanced Very High Resolution Radiometer (AVHRR) data to detect subsurface fire (subsurface hotspots) by proposing an efficient contextual algorithm. Although few algorithms based on the fixed-thresholding approach have been proposed for subsurface hotspot detection, however, for each application, thresholds have to be specifically tuned to cope with unique environmental conditions. The main objective of this paper is to develop an instrument-independent adaptive method by which direct threshold or multithreshold can be avoided. The proposed contextual algorithm is helpful to monitor subsurface hotspots with operational satellite data, such as the Jharia region of India, without making any region-specific guess in thresholding. Novelty of the proposed work lies in the fact that once the algorithmic model is developed for the particular region of interest after optimizing the model parameters, there is no need to optimize those parameters again for further satellite images. Hence, the developed model can be used for optimized automated detection and monitoring of subsurface hotspots for future images of the particular region of interest. The algorithm is adaptive in nature and uses vegetation index and different NOAA/AVHRR channel's statistics to detect hotspots in the region of interest. The performance of the algorithm is assessed in terms of sensitivity and specificity and compared with other well-known thresholding, techniques such as Otsu's thresholding, entropy-based thresholding, and existing contextual algorithm proposed by Flasse and Ceccato. The proposed algorithm is found to give better hotspot detection accuracy with lesser false alarm rate.

  15. Deficient morphological processing in adults with developmental dyslexia: another barrier to efficient word recognition?

    PubMed

    Schiff, Rachel; Raveh, Michal

    2007-05-01

    Research on dyslexia has focused on the phonological level of linguistic analysis. Here we extend the investigation of the linguistic competence of individuals with dyslexia to the morphological level of linguistic analysis. We examine whether adult Hebrew readers with dyslexia extract and represent morphemic units similarly to normal readers. Using the priming paradigm in the word fragment completion task, we measured the magnitude of morphological priming and contrasted this effect with the repetition priming effect. Students with normal reading ability showed the typical repetition priming effect. A comparable repetition priming effect was also found for the dyslexic group as a whole. However, when the dyslexics were classified into three subtypes according to their phonological and orthographic decoding skills, repetition priming effects were significant only for the phonological dyslexia subgroup but not for the surface or mixed dyslexia subgroups. Furthermore, students with normal reading ability showed strong morphological priming, comparable in strength to the repetition priming effect. In contrast, the dyslexic readers did not show morphological priming, neither the dyslexia group as a whole, nor any of the subgroups. Our results highlight an additional source for dyslexics' difficulties with word recognition which lie at the level of morphological processing. PMID:17557687

  16. Efficient estimation of the total number of acini in adult rat lung

    PubMed Central

    Barré, Sébastien F.; Haberthür, David; Stampanoni, Marco; Schittny, Johannes C.

    2014-01-01

    Abstract Pulmonary airways are subdivided into conducting and gas‐exchanging airways. An acinus is defined as the small tree of gas‐exchanging airways, which is fed by the most distal purely conducting airway. Until now a dissector of five consecutive sections or airway casts were used to count acini. We developed a faster method to estimate the number of acini in young adult rats. Right middle lung lobes were critical point dried or paraffin embedded after heavy metal staining and imaged by X‐ray micro‐CT or synchrotron radiation‐based X‐rays tomographic microscopy. The entrances of the acini were counted in three‐dimensional (3D) stacks of images by scrolling through them and using morphological criteria (airway wall thickness and appearance of alveoli). Segmentation stopper were placed at the acinar entrances for 3D visualizations of the conducting airways. We observed that acinar airways start at various generations and that one transitional bronchiole may serve more than one acinus. A mean of 5612 (±547) acini per lung and a mean airspace volume of 0.907 (±0.108) μL per acinus were estimated. In 60‐day‐old rats neither the number of acini nor the mean acinar volume did correlate with the body weight or the lung volume. PMID:24997068

  17. Efficient genome-wide detection and cataloging of EMS-induced mutations using exome capture and next-generation sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemical mutagenesis efficiently generates phenotypic variation in otherwise homogeneous genetic backgrounds, enabling functional analysis of genes. Advances in mutation detection have brought the utility of induced mutant populations on par with those produced by insertional mutagenesis, but system...

  18. Intrinsic detection efficiency of superconducting nanowire single photon detector in the modified hot spot model

    NASA Astrophysics Data System (ADS)

    Zotova, A. N.; Vodolazov, D. Yu

    2014-12-01

    We theoretically study the dependence of the intrinsic detection efficiency (IDE) of a superconducting nanowire single photon detector on the applied current, I, and magnetic field, H. We find that the current, at which the resistive state appears in the superconducting film, depends on the position of the hot spot (a region with suppressed superconductivity around the place where the photon has been absorbed) with respect to the edges of the film. This circumstance leads to inevitable smooth dependence IDE(I) when IDE ˜ 0.05-1, even for a homogenous straight superconducting film and in the absence of fluctuations. For IDE ≲ 0.05, a much sharper current dependence comes from the fluctuation-assisted vortex entry to the hot spot, which is located near the edge of the film. We find that a weak magnetic field strongly affects IDE when the photon detection is connected with fluctuation-assisted vortex entry to the hot spot (IDE \\ll 1), and it weakly affects IDE when the photon detection is connected with the current-induced vortex nucleation in the film with the hot spot (IDE ˜ 0.05-1).

  19. An efficient unsupervised fetal QRS complex detection from abdominal maternal ECG.

    PubMed

    Varanini, M; Tartarisco, G; Billeci, L; Macerata, A; Pioggia, G; Balocchi, R

    2014-08-01

    Non-invasive fetal heart rate is of great relevance in clinical practice to monitor fetal health state during pregnancy. To date, however, despite significant advances in the field of electrocardiography, the analysis of abdominal fetal ECG is considered a challenging problem for biomedical and signal processing communities. This is mainly due to the low signal-to-noise ratio of fetal ECG and difficulties in cancellation of maternal QRS complexes, motion and electromyographic artefacts. In this paper we present an efficient unsupervised algorithm for fetal QRS complex detection from abdominal multichannel signal recordings combining ICA and maternal ECG cancelling, which outperforms each single method. The signal is first pre-processed to remove impulsive artefacts, baseline wandering and power line interference. The following steps are then applied: maternal ECG extraction through independent component analysis (ICA); maternal QRS detection; maternal ECG cancelling through weighted singular value decomposition; enhancing of fetal ECG through ICA and fetal QRS detection. We participated in the Physionet/Computing in Cardiology Challenge 2013, obtaining the top official scores of the challenge (among 53 teams of participants) of event 1 and event 2 concerning fetal heart rate and fetal interbeat intervals estimation section. The developed algorithms are released as open-source on the Physionet website.

  20. An efficient method for miRNA detection and localization in crop plants.

    PubMed

    Rosas-Cárdenas, Flor de Fátima; Escobar-Guzmán, Rocío; Cruz-Hernández, Andrés; Marsch-Martínez, Nayelli; de Folter, Stefan

    2015-01-01

    microRNAs are a class of non-coding small RNAs (sRNAs) that are important regulators of gene expression at the post-transcriptional level by mRNA cleavage or translation inhibition. Another class of sRNAs are siRNAs, which also regulate gene expression but by causing DNA methylation. This epigenetic regulatory role has been observed for some miRNAs as well. The use of sRNAs allows the development of biotechnological applications in plants. To develop these types of applications, and to better understand the natural roles they play, it is important to be able to detect and to localize these sRNAs at the plant tissue level. Sometimes, in crop plants this can be challenging. Therefore, we developed a tissue printing hybridization protocol for easy and efficient detection of sRNAs and demonstrate this by the analysis of the spatio-temporal expression patterns of the miRNAs miR159 and miR164 in fruits of various crop plants. Moreover, we show the possibility to also detect the expression of miRNAs in fruit juice using a dot blot hybridization approach. PMID:25784917

  1. An efficient method for miRNA detection and localization in crop plants

    PubMed Central

    Rosas-Cárdenas, Flor de Fátima; Escobar-Guzmán, Rocío; Cruz-Hernández, Andrés; Marsch-Martínez, Nayelli; de Folter, Stefan

    2015-01-01

    microRNAs are a class of non-coding small RNAs (sRNAs) that are important regulators of gene expression at the post-transcriptional level by mRNA cleavage or translation inhibition. Another class of sRNAs are siRNAs, which also regulate gene expression but by causing DNA methylation. This epigenetic regulatory role has been observed for some miRNAs as well. The use of sRNAs allows the development of biotechnological applications in plants. To develop these types of applications, and to better understand the natural roles they play, it is important to be able to detect and to localize these sRNAs at the plant tissue level. Sometimes, in crop plants this can be challenging. Therefore, we developed a tissue printing hybridization protocol for easy and efficient detection of sRNAs and demonstrate this by the analysis of the spatio-temporal expression patterns of the miRNAs miR159 and miR164 in fruits of various crop plants. Moreover, we show the possibility to also detect the expression of miRNAs in fruit juice using a dot blot hybridization approach. PMID:25784917

  2. Efficient detection of secondary structure folded nucleic acids related to Alzheimer's disease based on junction probes.

    PubMed

    Li, Juan; Qi, Xiu-Juan; Du, Yan-Yan; Fu, Hua-E; Chen, Guo-Nan; Yang, Huang-Hao

    2012-01-01

    Single stranded DNA often forms stable secondary structures under physiological conditions. These DNA secondary structures play important physiological roles. However, the analysis of such secondary structure folded DNA is often complicated because of its high thermodynamic stability and slow hybridization kinetics. In this article, we demonstrate that Y-shaped junction probes could be used for rapid and highly efficient detection of secondary structure folded DNA. Our approach contained a molecular beacon (MB) probe and an assistant probe. In the absence of target, the MB probe failed to hybridize with the assistant probe. Whereas, the MB probe and the assistant probe could cooperatively unwind the secondary structure folded DNA target to form a ternary Y-shaped junction structure. In this condition, the MB probe was also opened, resulting in separating the fluorophores from the quenching moiety and emitting the fluorescence signal. This approach allowed for the highly sensitive detection of secondary structure folded DNA target, such as a tau specific DNA fragment related to Alzheimer's disease in this case. Additionally, this approach showed strong SNPs identifying capability. Furthermore, it was noteworthy that this newly proposed approach was capable of detecting secondary structure folded DNA target in cell lysate samples.

  3. Two-Dimensional Speckle Tracking Echocardiography Detects Subclinical Left Ventricular Systolic Dysfunction among Adult Survivors of Childhood, Adolescent, and Young Adult Cancer

    PubMed Central

    Yu, Anthony F.; Raikhelkar, Jayant; Zabor, Emily C.; Tonorezos, Emily S.; Moskowitz, Chaya S.; Adsuar, Roberto; Mara, Elton; Huie, Kevin; Oeffinger, Kevin C.; Steingart, Richard M.; Liu, Jennifer E.

    2016-01-01

    Two-dimensional speckle tracking echocardiography (2DSTE) provides a sensitive measure of left ventricular (LV) systolic function and may aid in the diagnosis of cardiotoxicity. 2DSTE was performed in a cross-sectional study of 134 patients (mean age: 31.4 ± 8.8 years; 55% male; mean time since diagnosis: 15.4 ± 9.4 years) previously treated with anthracyclines (mean cumulative dose: 320 ± 124 mg/m2), with (n = 52) or without (n = 82) mediastinal radiotherapy. The prevalence of LV systolic dysfunction, defined as fractional shortening < 27%, LV ejection fraction (LVEF) < 55%, and global longitudinal strain (GLS) ≤ 16%, was 5.2%, 6.0%, and 23.1%, respectively. Abnormal GLS was observed in 24 (18%) patients despite a normal LVEF. Indices of LV systolic function were similar regardless of anthracycline dose. However, GLS was worse (18.0 versus 19.0, p = 0.003) and prevalence of abnormal GLS was higher (36.5% versus 14.6%, p = 0.004) in patients treated with mediastinal radiotherapy. Mediastinal radiotherapy was associated with reduced GLS (p = 0.040) after adjusting for sex, age, and cumulative anthracycline dose. In adult survivors of childhood, adolescent, and young adult cancer, 2DSTE frequently detects LV systolic dysfunction despite a normal LVEF and may be useful for the long-term cardiac surveillance of adult cancer survivors. PMID:26942202

  4. Early Detection of Depression and Associated Risk Factors in Adults with Mild/Moderate Intellectual Disability

    ERIC Educational Resources Information Center

    McGillivray, Jane A.; McCabe, Marita P.

    2007-01-01

    The aim of this study was to determine the presentation and risk factors for depression in adults with mild/moderate intellectual disability (ID). A sample of 151 adults (83 males and 68 females) participated in a semi-structured interview. According to results on the Beck Depression Inventory II, 39.1% of participants evinced symptoms of…

  5. Validation and User Evaluation of a Sensor-Based Method for Detecting Mobility-Related Activities in Older Adults

    PubMed Central

    Geraedts, Hilde A. E.; Zijlstra, Wiebren; Van Keeken, Helco G.; Zhang, Wei; Stevens, Martin

    2015-01-01

    Regular physical activity is essential for older adults to stay healthy and independent. However, daily physical activity is generally low among older adults and mainly consists of activities such as standing and shuffling around indoors. Accurate measurement of this low-energy expenditure daily physical activity is crucial for stimulation of activity. The objective of this study was to assess the validity of a necklace-worn sensor-based method for detecting time-on-legs and daily life mobility related postures in older adults. In addition user opinion about the practical use of the sensor was evaluated. Twenty frail and non-frail older adults performed a standardized and free movement protocol in their own home. Results of the sensor-based method were compared to video observation. Sensitivity, specificity and overall agreement of sensor outcomes compared to video observation were calculated. Mobility was assessed based on time-on-legs. Further assessment included the categories standing, sitting, walking and lying. Time-on-legs based sensitivity, specificity and percentage agreement were good to excellent and comparable to laboratory outcomes in other studies. Category-based sensitivity, specificity and overall agreement were moderate to excellent. The necklace-worn sensor is considered an acceptable valid instrument for assessing home-based physical activity based upon time-on-legs in frail and non-frail older adults, but category-based assessment of gait and postures could be further developed. PMID:26361009

  6. A new efficient statistical test for detecting variability in the gene expression data.

    PubMed

    Mathur, Sunil; Dolo, Samuel

    2008-08-01

    DNA microarray technology allows researchers to monitor the expressions of thousands of genes under different conditions. The detection of differential gene expression under two different conditions is very important in microarray studies. Microarray experiments are multi-step procedures and each step is a potential source of variance. This makes the measurement of variability difficult because approach based on gene-by-gene estimation of variance will have few degrees of freedom. It is highly possible that the assumption of equal variance for all the expression levels may not hold. Also, the assumption of normality of gene expressions may not hold. Thus it is essential to have a statistical procedure which is not based on the normality assumption and also it can detect genes with differential variance efficiently. The detection of differential gene expression variance will allow us to identify experimental variables that affect different biological processes and accuracy of DNA microarray measurements.In this article, a new nonparametric test for scale is developed based on the arctangent of the ratio of two expression levels. Most of the tests available in literature require the assumption of normal distribution, which makes them inapplicable in many situations, and it is also hard to verify the suitability of the normal distribution assumption for the given data set. The proposed test does not require the assumption of the distribution for the underlying population and hence makes it more practical and widely applicable. The asymptotic relative efficiency is calculated under different distributions, which show that the proposed test is very powerful when the assumption of normality breaks down. Monte Carlo simulation studies are performed to compare the power of the proposed test with some of the existing procedures. It is found that the proposed test is more powerful than commonly used tests under almost all the distributions considered in the study. A

  7. Rapid, simple and efficient method for detection of viral genomes on raspberries.

    PubMed

    Perrin, A; Loutreul, J; Boudaud, N; Bertrand, I; Gantzer, C

    2015-11-01

    In recent years, foodborne viruses, especially human noroviruses (NoV) and hepatitis A virus (HAV), have been increasingly reported as the causes of foodborne disease outbreaks. Soft red fruits, especially raspberries, have a high incidence among the types of food concerned. Due to low infectious doses and low concentrations of enteric viruses in food samples, it is necessary to have an efficient and rapid detection method to implement prevention measures. A standard method for virus detection and quantification in food, including raspberries (XP CEN ISO/TS 15216-1 and -2, 2013) is currently available. This method proposes a consensus detection approach by RT-real time PCR (RT-qPCR) but also a virus extraction procedure based on the elution-concentration principle. In this study, an alternative method of extraction in which RNAs are directly extracted from food matrices (based on direct RNA extraction) has been optimized. First, each step was improved to make it a highly rapid, specific and simple method. Second, the standard virus concentration method was compared with the optimized direct RNA extraction one. Human enteric viral surrogates, Murine Norovirus (MNV) and F-specific RNA bacteriophage GA, were selected according to their adhesion properties and resistance to pH close to our main targets (NoV and HAV). Raspberries were artificially contaminated using two different techniques (immersion and spotting) in order to define a recovery rate and the amounts of virus recovered. Results showed that the direct RNA extraction method revealed significantly higher viral extraction efficiency (46.2%) than the elution-concentration method (20.3%), with similar proportions of inhibitors for both. In the same way with inoculation by spotting, the best recovery rate of GA phage (39.7% against 0.7%) and MNV (42.8% against 0.5%) was observed by direct RNA extraction. For the lowest concentrations of phage and virus in the immersion bath, only the direct RNA extraction method

  8. Efficient Personalized Mispronunciation Detection of Taiwanese-Accented English Speech Based on Unsupervised Model Adaptation and Dynamic Sentence Selection

    ERIC Educational Resources Information Center

    Wu, Chung-Hsien; Su, Hung-Yu; Liu, Chao-Hong

    2013-01-01

    This study presents an efficient approach to personalized mispronunciation detection of Taiwanese-accented English. The main goal of this study was to detect frequently occurring mispronunciation patterns of Taiwanese-accented English instead of scoring English pronunciations directly. The proposed approach quickly identifies personalized…

  9. High efficiency direct detection of ions from resonance ionization of sputtered atoms

    DOEpatents

    Gruen, D.M.; Pellin, M.J.; Young, C.E.

    1985-01-16

    A method and apparatus are provided for trace and other quantitative analysis with high efficiency of a component in a sample, with the analysis involving the removal by ion or other bombardment of a small quantity of ion and neutral atom groups from the sample, the conversion of selected neutral atom groups to photoions by laser initiated resonance ionization spectroscopy, the selective deflection of the photoions for separation from original ion group emanating from the sample, and the detection of the photoions as a measure of the quantity of the component. In some embodiments, the original ion group is accelerated prior to the RIS step for separation purposes. Noise and other interference are reduced by shielding the detector from primary and secondary ions and deflecting the photoions sufficiently to avoid the primary and secondary ions.

  10. High efficiency direct detection of ions from resonance ionization of sputtered atoms

    DOEpatents

    Gruen, Dieter M.; Pellin, Michael J.; Young, Charles E.

    1986-01-01

    A method and apparatus are provided for trace and other quantitative analysis with high efficiency of a component in a sample, with the analysis involving the removal by ion or other bombardment of a small quantity of ion and neutral atom groups from the sample, the conversion of selected neutral atom groups to photoions by laser initiated resonance ionization spectroscopy, the selective deflection of the photoions for separation from original ion group emanating from the sample, and the detection of the photoions as a measure of the quantity of the component. In some embodiments, the original ion group is accelerated prior to the RIS step for separation purposes. Noise and other interference are reduced by shielding the detector from primary and secondary ions and deflecting the photoions sufficiently to avoid the primary and secondary ions.

  11. Ultraviolet quantum detection efficiency of potassium bromide as an opaque photocathode applied to microchannel plates

    NASA Technical Reports Server (NTRS)

    Siegmund, Oswald H. W.; Everman, E.; Vallerga, J. V.; Sokolowski, J.; Lampton, M.

    1987-01-01

    The quantum detection efficiency (QDE) of potassium bromide as a photocathode applied directly to the surface of a microchannel plate over the 250-1600 A wavelength range has been measured. The contributions of the photocathode material in the channels and on the interchannel web to the QDE have been determined. Two broad peaks in the QDE centered at about 450 and about 1050 A are apparent, the former with about 50 percent peak QDE and the latter with about 40 percent peak QDE. The photoelectric threshold is observed at about 1600 A, and there is a narrow QDE minimum at about 750 A which correlates with 2X the band gap energy for KBr. The angular variation of the QDE from 0 to 40 deg to the channnel axis has also been examined. The stability of Kbr with time is shown to be good with no significant degradation of QDE at wavelengths below 1216 A over a 15-day period in air.

  12. Analysis of the scatter effect on detective quantum efficiency of digital mammography

    NASA Astrophysics Data System (ADS)

    Park, Jiwoong; Yun, Seungman; Kim, Dong Woon; Baek, Cheol-Ha; Youn, Hanbean; Jeon, Hosang; Kim, Ho Kyung

    2016-03-01

    The scatter effect on detective quantum efficiency (DQE) of digital mammography is investigated using the cascaded-systems model. The cascaded-systems model includes a scatter-reduction device as a binomial selection stage. Quantum-noise-limited operation approximates the system DQE into the multiplication form of the scatter-reduction device DQE and the conventional detector DQE. The developed DQE model is validated in comparisons with the measured results using a CMOS flat-panel detector under scatter environments. For various scatter-reduction devices, the slot-scan method shows the best scatter-cleanup performance in terms of DQE, and the scatter-cleanup performance of the conventional one-dimensional grid is rather worse than the air gap. The developed model can also be applied to general radiography and will be very useful for a better design of imaging chain.

  13. Ultramild protein-mediated click chemistry creates efficient oligonucleotide probes for targeting and detecting nucleic acids.

    PubMed

    Nåbo, Lina J; Madsen, Charlotte S; Jensen, Knud J; Kongsted, Jacob; Astakhova, Kira

    2015-05-26

    Functionalized synthetic oligonucleotides are finding growing applications in research, clinical studies, and therapy. However, it is not easy to prepare them in a biocompatible and highly efficient manner. We report a new strategy to synthesize oligonucleotides with promising nucleic acid targeting and detection properties. We focus in particular on the pH sensitivity of these new probes and their high target specificity. For the first time, human copper(I)-binding chaperon Cox17 was applied to effectively catalyze click labeling of oligonucleotides. This was performed under ultramild conditions with fluorophore, peptide, and carbohydrate azide derivatives. In thermal denaturation studies, the modified probes showed specific binding to complementary DNA and RNA targets. Finally, we demonstrated the pH sensitivity of the new rhodamine-based fluorescent probes in vitro and rationalize our results by electronic structure calculations.

  14. Validation of efficiency tracing and zero detection threshold techniques using liquid scintillation analyser TriCarb.

    PubMed

    Reddy, P J; Bhade, S P D; Babu, D A R; Sharma, D N

    2011-11-01

    Efficiency tracing with unquenched 14C and zero detection threshold with unquenched 3H as tracers are practical and simple techniques which have been implemented to quantify the activity of various beta emitters using liquid scintillation analyser. These techniques are used to study the influence of quench level on activity quantification and the activity levels up to which these techniques are applicable. The results indicate that, for an activity level of 166.67 Bq, both the techniques are in good agreement with the reference activity with a relative discrepancy of ≤4.6 %. The relative discrepancy of ~10 % is observed for extreme quench values of ~111. For all the radionuclides with the activity level of 1.67 Bq, the uncertainty in activity quantification raises to ~8 % and for the activity level from 8.33 to 100 Bq, the uncertainty reduces to 1 %. PMID:21196460

  15. Better estimation of the detection efficiency for total radium in drinking water samples

    SciTech Connect

    Holbert, K.E.; Stewart, B.D.

    1993-12-31

    Radium measurements in drinking water are complicated by the buildup of daughter radionuclides. The EPA method of calculating the ingrowth factor (R) of radium daughter products does not account for the difference in self-absorption between the radium alpha emissions and the higher energy alpha emissions from the daughters. A relatively simple procedure is developed which compensates for the difference in detection efficiency. Rather than multiply the exponential buildup of daughters by a factor of three (3), a new fitted parameter His introduced. Results have shown values of H that range from 3 to 5 for increasing precipitate masses from 7 to 100 mg, respectively. Utilization of this fitted parameter typically yields improvements of 5%, but can easily provide corrections of 20% or more, depending on the amount of ingrowth prior to the start of the count. The theoretical basis and procedure for determining H are presented.

  16. Combined analytical FEM approach for efficient simulation of Lamb wave damage detection.

    PubMed

    Shen, Yanfeng; Giurgiutiu, Victor

    2016-07-01

    Lamb waves have been widely explored as a promising inspection tool for non-destructive evaluation (NDE) and structural health monitoring (SHM). This article presents a combined analytical finite element model (FEM) approach (CAFA) for the accurate, efficient, and versatile simulation of 2-D Lamb wave propagation and interaction with damage. CAFA used a global analytical solution to model wave generation, propagation, scattering, mode conversion, and detection, while the wave-damage interaction coefficients (WDICs) were extracted from harmonic analysis of local FEM with non-reflective boundaries (NRB). The analytical procedure was coded using MATLAB, and a predictive simulation tool called WaveFormRevealer 2-D was developed. The methodology of obtaining WDICs from local FEM was presented. Case studies were carried out for Lamb wave propagation in a pristine plate and a damaged plate. CAFA predictions compared well with full scale multi-physics FEM simulations and experiments with scanning laser Doppler vibrometry (SLDV), while achieving remarkable performance in computational efficiency and computer resource saving compared with conventional FEM. PMID:27085109

  17. MIL-M-38510/470 test vectors: Fault detection efficiency measurement via hardware fault simulation. [rca 1802 microprocessor

    NASA Technical Reports Server (NTRS)

    Timoc, C. C.

    1980-01-01

    The stuck fault detection efficiency of the test vectors developed for the MIL-M-38510/470 NASA was measured using a hardware stuck fault simulator for the 1802 microprocessor. Thirty-nine stuck faults were not detected out of a total of 874 injected into the combinatorial and sequential parts of the microprocessor. Since undetected faults can create catastrophic errors in equipment designed for high reliability applications, it is recommended that the MIL-M-38510/470 NASA be enhanced with additional test vectors so as to achieve 100% stuck fault detection efficiency.

  18. Detective quantum efficiency of photon-counting x-ray detectors

    SciTech Connect

    Tanguay, Jesse; Yun, Seungman; Kim, Ho Kyung; Cunningham, Ian A.

    2015-01-15

    Purpose: Single-photon-counting (SPC) x-ray imaging has the potential to improve image quality and enable novel energy-dependent imaging methods. Similar to conventional detectors, optimizing image SPC quality will require systems that produce the highest possible detective quantum efficiency (DQE). This paper builds on the cascaded-systems analysis (CSA) framework to develop a comprehensive description of the DQE of SPC detectors that implement adaptive binning. Methods: The DQE of SPC systems can be described using the CSA approach by propagating the probability density function (PDF) of the number of image-forming quanta through simple quantum processes. New relationships are developed to describe PDF transfer through serial and parallel cascades to accommodate scatter reabsorption. Results are applied to hypothetical silicon and selenium-based flat-panel SPC detectors including the effects of reabsorption of characteristic/scatter photons from photoelectric and Compton interactions, stochastic conversion of x-ray energy to secondary quanta, depth-dependent charge collection, and electronic noise. Results are compared with a Monte Carlo study. Results: Depth-dependent collection efficiency can result in substantial broadening of photopeaks that in turn may result in reduced DQE at lower x-ray energies (20–45 keV). Double-counting interaction events caused by reabsorption of characteristic/scatter photons may result in falsely inflated image signal-to-noise ratio and potential overestimation of the DQE. Conclusions: The CSA approach is extended to describe signal and noise propagation through photoelectric and Compton interactions in SPC detectors, including the effects of escape and reabsorption of emission/scatter photons. High-performance SPC systems can be achieved but only for certain combinations of secondary conversion gain, depth-dependent collection efficiency, electronic noise, and reabsorption characteristics.

  19. Advances in multiplex PCR: balancing primer efficiencies and improving detection success

    PubMed Central

    Sint, Daniela; Raso, Lorna; Traugott, Michael

    2012-01-01

    1. Multiplex PCR is a valuable tool in many biological studies but it is a multifaceted procedure that has to be planned and optimised thoroughly to achieve robust and meaningful results. In particular, primer concentrations have to be adjusted to assure an even amplification of all targeted DNA fragments. Until now, total DNA extracts were used for balancing primer efficiencies; however, the applicability for comparisons between taxa or different multiple-copy genes was limited owing to the unknown number of template molecules present per total DNA. 2. Based on a multiplex system developed to track trophic interactions in high Alpine arthropods, we demonstrate a fast and easy way of generating standardised DNA templates. These were then used to balance the amplification success for the different targets and to subsequently determine the sensitivity of each primer pair in the multiplex PCR. 3. In the current multiplex assay, this approach led to an even amplification success for all seven targeted DNA fragments. Using this balanced multiplex PCR, methodological bias owing to variation in primer efficiency will be avoided when analysing field-derived samples. 4. The approach outlined here allows comparing multiplex PCR sensitivity, independent of the investigated species, genome size or the targeted genes. The application of standardised DNA templates not only makes it possible to optimise primer efficiency within a given multiplex PCR, but it also offers to adjust and/or to compare the sensitivity between different assays. Along with other factors that influence the success of multiplex reactions, and which we discuss here in relation to the presented detection system, the adoption of this approach will allow for direct comparison of multiplex PCR data between systems and studies, enhancing the utility of this assay type. PMID:23549328

  20. Association between body mass index and arsenic methylation efficiency in adult women from southwest U.S. and northwest Mexico

    SciTech Connect

    Gomez-Rubio, Paulina; Roberge, Jason; Arendell, Leslie; Harris, Robin B.; O'Rourke, Mary K.; Chen, Zhao; Cantu-Soto, Ernesto; Meza-Montenegro, Maria M.; Billheimer, Dean; Lu Zhenqiang; Klimecki, Walter T.

    2011-04-15

    Human arsenic methylation efficiency has been consistently associated with arsenic-induced disease risk. Interindividual variation in arsenic methylation profiles is commonly observed in exposed populations, and great effort has been put into the study of potential determinants of this variability. Among the factors that have been evaluated, body mass index (BMI) has not been consistently associated with arsenic methylation efficiency; however, an underrepresentation of the upper BMI distribution was commonly observed in these studies. This study investigated potential factors contributing to variations in the metabolism of arsenic, with specific interest in the effect of BMI where more than half of the population was overweight or obese. We studied 624 adult women exposed to arsenic in drinking water from three independent populations. Multivariate regression models showed that higher BMI, arsenic (+ 3 oxidation state) methyltransferase (AS3MT) genetic variant 7388, and higher total urinary arsenic were significantly associated with low percentage of urinary arsenic excreted as monomethylarsonic acid (%uMMA) or high ratio between urinary dimethylarsinic acid and uMMA (uDMA/uMMA), while AS3MT genetic variant M287T was associated with high %uMMA and low uDMA/uMMA. The association between BMI and arsenic methylation efficiency was also evident in each of the three populations when studied separately. This strong association observed between high BMI and low %uMMA and high uDMA/uMMA underscores the importance of BMI as a potential arsenic-associated disease risk factor, and should be carefully considered in future studies associating human arsenic metabolism and toxicity.

  1. Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways.

    PubMed

    Wang, Zenghui; Feng, Philip X-L

    2016-01-01

    Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405 nm). We also find that the vacuum gap resulting from the widely used 300 nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout. PMID:27464908

  2. Enhanced detection and study of murine norovirus-1 using a more efficient microglial cell line

    PubMed Central

    Cox, Courtney; Cao, Shengbo; Lu, Yuanan

    2009-01-01

    Background Human Noroviruses are the predominant cause of non-bacterial gastroenteritis worldwide. To facilitate prevention and control, a norovirus isolated from mice can provide a model to understand human noroviruses. To establish optimal viral infectivity conditions for murine noroviruses, several cell lines of hematopoietic lineage, including murine BV-2, RAW 264.7, and TIB, as well as human CHME-5, were tested comparatively for their sensitivity to murine norovirus-1. Results Except for CHME-5, all three murine-derived cell lines were susceptible to MNV infection. Viral infection of these cells was confirmed by RT-PCR. Using both viral plaque and replication assays, BV-2 and RAW 264.7 cells were determined to have comparable sensitivities to MNV-1 infection. Comparisons of cell growth characteristics, general laboratory handling and potential in-field applications suggest the use of BV-2 to be more advantageous. Conclusion Results obtained from these studies demonstrate that an immortalized microglial cell line can support MNV-1 replication and provides a more efficient method to detect and study murine noroviruses, facilitating future investigations using MNV-1 as a model to study, detect, and control Human Norovirus. PMID:19903359

  3. The effects of x-ray beam hardening on detective quantum efficiency and radiation dose.

    PubMed

    Wong, Molly Donovan; Wu, Xizeng; Liu, Hong

    2011-01-01

    The goal of this preliminary study was to investigate the effects of x-ray beam hardening on the detective quantum efficiency (DQE) and the radiation dose of an inline x-ray imaging system. The ability to decrease the risk of harmful radiation to the patient without compromising the detection capability would more effectively balance the tradeoff between image quality and radiation dose, and therefore benefit the fields of diagnostic x-ray imaging, especially mammography. The DQE and the average glandular dose were both calculated under the same experimental conditions for a range of beam hardening levels, corresponding to no added beam hardening and two thicknesses each of Rhodium (Rh) and Molybdenum (Mo) filters. The dose calculation results demonstrate a reduction of 15% to 24% for the range of beam hardening levels. The comparison of all quantities comprising the DQE exhibit very close correlation between the results obtained without added beam hardening to the results corresponding to the range of beam hardening levels. For the specific experimental conditions utilized in this preliminary study, the results are an indication that the use of beam hardening holds the potential to reduce the radiation dose without decreasing the performance of the system. Future studies will seek to apply this method in a clinical environment and perform a comprehensive image quality evaluation, in an effort to further evaluate the potential of beam hardening to balance the tradeoff between dose and image quality.

  4. Al:ZnO thin film: An efficient matrix for cholesterol detection

    NASA Astrophysics Data System (ADS)

    Batra, Neha; Tomar, Monika; Gupta, Vinay

    2012-12-01

    Al doped ZnO thin film (Al:ZnO) has been realized as a potential matrix for the development of efficient cholesterol biosensor. The correlation between the structural and electrical properties of ZnO thin film with varying Al doping concentration (1% to 5%) and their cyclic voltammetric (CV) response has been studied. 2% Al doped ZnO films were found to give the best CV response and were further utilized for immobilization of cholesterol oxidase (ChOx) to detect cholesterol. Amperometric and photometric studies reveal that the prepared bioelectrode based on 2% Al doped ZnO matrix (ChOx/Al:ZnO/Pt/glass) is highly sensitive (sensitivity = 173 μAmM-1 cm-2) to the detection of cholesterol in the wide range from 0.6-12.9 mM (25-500 mg/dl). A relatively low value of enzyme's kinetic parameter (Michaelis menten constant, 2.53 mM) indicates enhanced affinity of the immobilized ChOx toward cholesterol. The prepared bioelectrode is found to be exhibiting high shelf life (10 weeks) having negligible interference with the presence of other biomolecules in human serum indicating promising application of Al doped ZnO thin films for cholesterol biosensing.

  5. High-efficiency molecular counting in solution: Single-molecule detection in electrodynamically focused microdroplet streams

    SciTech Connect

    Lermer, N.; Barnes, M.D.; Kung, C.Y.; Whitten, W.B.; Ramsey, J.M.

    1997-06-01

    We report fluorescence detection of individual rhodamine 6G molecules using a linear quadrupole to focus streams of microdroplets through the waist of a counterpropagating cw Ar{sup +} laser. Since the terminal velocity scales as the square of the droplet diameter, the droplet-laser interaction time was `tunable` between 5 and 200 ms by using water samples spiked with a small, variable (2-5% v/v) amount of glycerol. Fluorescence bursts from droplets containing single molecules were clearly distinguished from the blanks in real time with an average signal-to-noise ratio of about 10, limited primarily by photobleaching and droplet size fluctuations (<1%). The volume throughput rates associated with this approach (approx. 10 pL/s) are roughly 10{sup 3} higher than those associated with particle levitation techniques, with minimal sacrifice in sensitivity. Total molecular detection efficiencies of about 80% (at >99% confidence) were obtained for 100 and 15 fM rhodamine 6G solutions, in good agreement with detailed theoretical calculations and statistical limitations. 39 refs., 7 figs., 1 tab.

  6. Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways.

    PubMed

    Wang, Zenghui; Feng, Philip X-L

    2016-07-28

    Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405 nm). We also find that the vacuum gap resulting from the widely used 300 nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout.

  7. Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways

    NASA Astrophysics Data System (ADS)

    Wang, Zenghui; Feng, Philip X.-L.

    2016-07-01

    Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405 nm). We also find that the vacuum gap resulting from the widely used 300 nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout.

  8. Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways

    PubMed Central

    Wang, Zenghui; Feng, Philip X.-L.

    2016-01-01

    Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405 nm). We also find that the vacuum gap resulting from the widely used 300 nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout. PMID:27464908

  9. Molecular detection of Bartonella spp. in deer ked pupae, adult keds and moose blood in Finland.

    PubMed

    Korhonen, E M; Pérez Vera, C; Pulliainen, A T; Sironen, T; Aaltonen, K; Kortet, R; Härkönen, L; Härkönen, S; Paakkonen, T; Nieminen, P; Mustonen, A-M; Ylönen, H; Vapalahti, O

    2015-02-01

    The deer ked (Lipoptena cervi) is a haematophagous ectoparasite of cervids that harbours haemotrophic Bartonella. A prerequisite for the vector competence of the deer ked is the vertical transmission of the pathogen from the mother to its progeny and transstadial transmission from pupa to winged adult. We screened 1154 pupae and 59 pools of winged adult deer keds from different areas in Finland for Bartonella DNA using PCR. Altogether 13 pupa samples and one winged adult deer ked were positive for the presence of Bartonella DNA. The amplified sequences were closely related to either B. schoenbuchensis or B. bovis. The same lineages were identified in eight blood samples collected from free-ranging moose. This is the first demonstration of Bartonella spp. DNA in a winged adult deer ked and, thus, evidence for potential transstadial transmission of Bartonella spp. in the species.

  10. A spatio-temporal detective quantum efficiency and its application to fluoroscopic systems

    SciTech Connect

    Friedman, S. N.; Cunningham, I. A.

    2010-11-15

    Purpose: Fluoroscopic x-ray imaging systems are used extensively in spatio-temporal detection tasks and require a spatio-temporal description of system performance. No accepted metric exists that describes spatio-temporal fluoroscopic performance. The detective quantum efficiency (DQE) is a metric widely used in radiography to quantify system performance and as a surrogate measure of patient ''dose efficiency.'' It has been applied previously to fluoroscopic systems with the introduction of a temporal correction factor. However, the use of a temporally-corrected DQE does not provide system temporal information and it is only valid under specific conditions, many of which are not likely to be satisfied by suboptimal systems. The authors propose a spatio-temporal DQE that describes performance in both space and time and is applicable to all spatio-temporal quantum-based imaging systems. Methods: The authors define a spatio-temporal DQE (two spatial-frequency axes and one temporal-frequency axis) in terms of a small-signal spatio-temporal modulation transfer function (MTF) and spatio-temporal noise power spectrum (NPS). Measurements were made on an x-ray image intensifier-based bench-top system using continuous fluoroscopy with an RQA-5 beam at 3.9 {mu}R/frame and hardened 50 kVp beam (0.8 mm Cu filtration added) at 1.9 {mu}R/frame. Results: A zero-frequency DQE value of 0.64 was measured under both conditions. Nonideal performance was noted at both larger spatial and temporal frequencies; DQE values decreased by {approx}50% at the cutoff temporal frequency of 15 Hz. Conclusions: The spatio-temporal DQE enables measurements of decreased temporal system performance at larger temporal frequencies analogous to previous measurements of decreased (spatial) performance. This marks the first time that system performance and dose efficiency in both space and time have been measured on a fluoroscopic system using DQE and is the first step toward the generalized use of DQE on

  11. Fiber-optic integration and efficient detection schemes for optomechanical resonators

    NASA Astrophysics Data System (ADS)

    Cohen, Justin D.

    With the advent of the laser in the year 1960, the field of optics experienced a renaissance from what was considered to be a dull, solved subject to an active area of development, with applications and discoveries which are yet to be exhausted 55 years later. Light is now nearly ubiquitous not only in cutting-edge research in physics, chemistry, and biology, but also in modern technology and infrastructure. One quality of light, that of the imparted radiation pressure force upon reflection from an object, has attracted intense interest from researchers seeking to precisely monitor and control the motional degrees of freedom of an object using light. These optomechanical interactions have inspired myriad proposals, ranging from quantum memories and transducers in quantum information networks to precision metrology of classical forces. Alongside advances in micro- and nano-fabrication, the burgeoning field of optomechanics has yielded a class of highly engineered systems designed to produce strong interactions between light and motion. Optomechanical crystals are one such system in which the patterning of periodic holes in thin dielectric films traps both light and sound waves to a micro-scale volume. These devices feature strong radiation pressure coupling between high-quality optical cavity modes and internal nanomechanical resonances. Whether for applications in the quantum or classical domain, the utility of optomechanical crystals hinges on the degree to which light radiating from the device, having interacted with mechanical motion, can be collected and detected in an experimental apparatus consisting of conventional optical components such as lenses and optical fibers. While several efficient methods of optical coupling exist to meet this task, most are unsuitable for the cryogenic or vacuum integration required for many applications. The first portion of this dissertation will detail the development of robust and efficient methods of optically coupling

  12. Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in Hiv-positive adults

    PubMed Central

    Shah, Maunank; Hanrahan, Colleen; Wang, Zhuo Yu; Dendukuri, Nandini; Lawn, Stephen D; Denkinger, Claudia M; Steingart, Karen R

    2016-01-01

    Background Rapid detection of tuberculosis (TB) among people living with human immunodeficiency virus (HIV) is a global health priority. HIV-associated TB may have different clinical presentations and is challenging to diagnose. Conventional sputum tests have reduced sensitivity in HIV-positive individuals, who have higher rates of extrapulmonary TB compared with HIV-negative individuals. The lateral flow urine lipoarabinomannan assay (LF-LAM) is a new, commercially available point-of-care test that detects lipoarabinomannan (LAM), a lipopolysaccharide present in mycobacterial cell walls, in people with active TB disease. Objectives To assess the accuracy of LF-LAM for the diagnosis of active TB disease in HIV-positive adults who have signs and symptoms suggestive of TB (TB diagnosis).To assess the accuracy of LF-LAM as a screening test for active TB disease in HIV-positive adults irrespective of signs and symptoms suggestive of TB (TB screening). Search methods We searched the following databases without language restriction on 5 February 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE (PubMed,1966); EMBASE (OVID, from 1980); Science Citation Index Expanded (SCI-EXPANDED, from 1900), Conference Proceedings Citation Index-Science (CPCI-S, from 1900), and BIOSIS Previews (from 1926) (all three using the Web of Science platform; MEDION; LILACS (BIREME, from 1982); SCOPUS (from 1995); the metaRegister of Controlled Trials (mRCT); the search portal of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); and ProQuest Dissertations & Theses A&l (from 1861). Selection criteria Eligible study types included randomized controlled trials, cross-sectional studies, and cohort studies that determined LF-LAM accuracy for TB against a microbiological reference standard (culture or nucleic acid amplification test from any body site). A higher quality reference standard was one in which two or more specimen types were

  13. Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in Hiv-positive adults

    PubMed Central

    Shah, Maunank; Hanrahan, Colleen; Wang, Zhuo Yu; Dendukuri, Nandini; Lawn, Stephen D; Denkinger, Claudia M; Steingart, Karen R

    2016-01-01

    Background Rapid detection of tuberculosis (TB) among people living with human immunodeficiency virus (HIV) is a global health priority. HIV-associated TB may have different clinical presentations and is challenging to diagnose. Conventional sputum tests have reduced sensitivity in HIV-positive individuals, who have higher rates of extrapulmonary TB compared with HIV-negative individuals. The lateral flow urine lipoarabinomannan assay (LF-LAM) is a new, commercially available point-of-care test that detects lipoarabinomannan (LAM), a lipopolysaccharide present in mycobacterial cell walls, in people with active TB disease. Objectives To assess the accuracy of LF-LAM for the diagnosis of active TB disease in HIV-positive adults who have signs and symptoms suggestive of TB (TB diagnosis).To assess the accuracy of LF-LAM as a screening test for active TB disease in HIV-positive adults irrespective of signs and symptoms suggestive of TB (TB screening). Search methods We searched the following databases without language restriction on 5 February 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE (PubMed,1966); EMBASE (OVID, from 1980); Science Citation Index Expanded (SCI-EXPANDED, from 1900), Conference Proceedings Citation Index-Science (CPCI-S, from 1900), and BIOSIS Previews (from 1926) (all three using the Web of Science platform; MEDION; LILACS (BIREME, from 1982); SCOPUS (from 1995); the metaRegister of Controlled Trials (mRCT); the search portal of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); and ProQuest Dissertations & Theses A&l (from 1861). Selection criteria Eligible study types included randomized controlled trials, cross-sectional studies, and cohort studies that determined LF-LAM accuracy for TB against a microbiological reference standard (culture or nucleic acid amplification test from any body site). A higher quality reference standard was one in which two or more specimen types were

  14. Development of a sensitive method to extract and detect low numbers of Cryptosporidium oocysts from adult cattle faecal samples.

    PubMed

    Wells, B; Thomson, S; Ensor, H; Innes, E A; Katzer, F

    2016-08-30

    Cryptosporidium transmission studies to date have concluded that adult cattle are not a significant source of oocysts contributing to clinical cryptosporidiosis in calves on farm. However current methods of sample processing have been optimised for calf faecal samples and may be less sensitive when used on adult samples due to lower numbers of oocysts and larger size of samples. A modified and novel method of oocyst extraction and concentration was developed and applied in an experiment involving spiking adult cattle faecal samples with known concentrations of Cryptosporidium oocysts. The results showed an increased sensitivity of detection from 100oocysts/g of faecal sample using conventional protocols to 5oocysts/g using the newly developed method. As it is important to be able to accurately assess the contribution of adult ruminants to the transmission of Cryptosporidium, both on farm and in the environment, the development of the techniques described here is likely to make an important contribution to Cryptosporidium transmission studies in future and in subsequent control strategies aimed at the reduction of Cryptosporidium infection in calves on farm. PMID:27523933

  15. Development of a sensitive method to extract and detect low numbers of Cryptosporidium oocysts from adult cattle faecal samples.

    PubMed

    Wells, B; Thomson, S; Ensor, H; Innes, E A; Katzer, F

    2016-08-30

    Cryptosporidium transmission studies to date have concluded that adult cattle are not a significant source of oocysts contributing to clinical cryptosporidiosis in calves on farm. However current methods of sample processing have been optimised for calf faecal samples and may be less sensitive when used on adult samples due to lower numbers of oocysts and larger size of samples. A modified and novel method of oocyst extraction and concentration was developed and applied in an experiment involving spiking adult cattle faecal samples with known concentrations of Cryptosporidium oocysts. The results showed an increased sensitivity of detection from 100oocysts/g of faecal sample using conventional protocols to 5oocysts/g using the newly developed method. As it is important to be able to accurately assess the contribution of adult ruminants to the transmission of Cryptosporidium, both on farm and in the environment, the development of the techniques described here is likely to make an important contribution to Cryptosporidium transmission studies in future and in subsequent control strategies aimed at the reduction of Cryptosporidium infection in calves on farm.

  16. Effect of signal-temporal uncertainty in children and adults: Tone detection in noise or a random-frequency masker

    PubMed Central

    Bonino, Angela Yarnell; Leibold, Lori J.; Buss, Emily

    2013-01-01

    A cue indicating when in time to listen can improve adults' tone detection thresholds, particularly for conditions that produce substantial informational masking. The purpose of this study was to determine if 5- to 13-yr-old children likewise benefit from a light cue indicating when in time to listen for a masked pure-tone signal. Each listener was tested in one of two continuous maskers: Broadband noise (low informational masking) or a random-frequency, two-tone masker (high informational masking). Using a single-interval method of constant stimuli, detection thresholds were measured for two temporal conditions: (1) Temporally-defined, with the listening interval defined by a light cue, and (2) temporally-uncertain, with no light cue. Thresholds estimated from psychometric functions fitted to the data indicated that children and adults benefited to the same degree from the visual cue. Across listeners, the average benefit of a defined listening interval was 1.8 dB in the broadband noise and 8.6 dB in the random-frequency, two-tone masker. Thus, the benefit of knowing when in time to listen was more robust for conditions believed to be dominated by informational masking. An unexpected finding of this study was that children's thresholds were comparable to adults' in the random-frequency, two-tone masker. PMID:25669256

  17. Effect of signal-temporal uncertainty in children and adults: tone detection in noise or a random-frequency masker.

    PubMed

    Bonino, Angela Yarnell; Leibold, Lori J; Buss, Emily

    2013-12-01

    A cue indicating when in time to listen can improve adults' tone detection thresholds, particularly for conditions that produce substantial informational masking. The purpose of this study was to determine if 5- to 13-yr-old children likewise benefit from a light cue indicating when in time to listen for a masked pure-tone signal. Each listener was tested in one of two continuous maskers: Broadband noise (low informational masking) or a random-frequency, two-tone masker (high informational masking). Using a single-interval method of constant stimuli, detection thresholds were measured for two temporal conditions: (1) Temporally-defined, with the listening interval defined by a light cue, and (2) temporally-uncertain, with no light cue. Thresholds estimated from psychometric functions fitted to the data indicated that children and adults benefited to the same degree from the visual cue. Across listeners, the average benefit of a defined listening interval was 1.8 dB in the broadband noise and 8.6 dB in the random-frequency, two-tone masker. Thus, the benefit of knowing when in time to listen was more robust for conditions believed to be dominated by informational masking. An unexpected finding of this study was that children's thresholds were comparable to adults' in the random-frequency, two-tone masker.

  18. Effective detective quantum efficiency for two mammography systems: Measurement and comparison against established metrics

    SciTech Connect

    Salvagnini, Elena; Bosmans, Hilde; Marshall, Nicholas W.; Struelens, Lara

    2013-10-15

    Purpose: The aim of this paper was to illustrate the value of the new metric effective detective quantum efficiency (eDQE) in relation to more established measures in the optimization process of two digital mammography systems. The following metrics were included for comparison against eDQE: detective quantum efficiency (DQE) of the detector, signal difference to noise ratio (SdNR), and detectability index (d′) calculated using a standard nonprewhitened observer with eye filter.Methods: The two systems investigated were the Siemens MAMMOMAT Inspiration and the Hologic Selenia Dimensions. The presampling modulation transfer function (MTF) required for the eDQE was measured using two geometries: a geometry containing scattered radiation and a low scatter geometry. The eDQE, SdNR, and d′ were measured for poly(methyl methacrylate) (PMMA) thicknesses of 20, 40, 60, and 70 mm, with and without the antiscatter grid and for a selection of clinically relevant target/filter (T/F) combinations. Figures of merit (FOMs) were then formed from SdNR and d′ using the mean glandular dose as the factor to express detriment. Detector DQE was measured at energies covering the range of typical clinically used spectra.Results: The MTF measured in the presence of scattered radiation showed a large drop at low spatial frequency compared to the low scatter method and led to a corresponding reduction in eDQE. The eDQE for the Siemens system at 1 mm{sup −1} ranged between 0.15 and 0.27, depending on T/F and grid setting. For the Hologic system, eDQE at 1 mm{sup −1} varied from 0.15 to 0.32, again depending on T/F and grid setting. The eDQE results for both systems showed that the grid increased the system efficiency for PMMA thicknesses of 40 mm and above but showed only small sensitivity to T/F setting. While results of the SdNR and d′ based FOMs confirmed the eDQE grid position results, they were also more specific in terms of T/F selection. For the Siemens system at 20 mm PMMA

  19. Microlensing candidate selection and detection efficiency for the SuperMACHO Dark Matter search

    NASA Astrophysics Data System (ADS)

    Garg, Arti

    One of the outstanding questions in modern cosmology is understanding the composition of the Dark Matter within our own Galaxy. The 5.7 year MACHO project which was completed in 2000, provided a rather vexing answer to this question. The MACHO project sought to place constraints on the fraction of the Galactic Dark Matter composed of MAssive Compact Halo Objects (MACHOs), or sub- stellar mass objects in the Milky Way halo. To accomplish this goal, the MACHO team measured the rate of gravitational microlensing toward the Magellanic Clouds to infer the MACHO concentration along the line-of-sight. The project's finding was vexing in that while the largest Milky Way halo mass fraction consistent with the results was not sufficient to explain all the "missing" matter in the Galaxy, the rate of microlensing observed could not be explained by known populations of objects. The SuperMACHO project seeks to independently verify the optical depth toward the Large Magellanic Cloud and also provide additional clues regarding the location of the lens. By determining the differential rate of microlensing across the face of the LMC, SuperMACHO distinguishes between "screen-" and "self-" lensing scenarios. This thesis describes the selection criteria used to arrive at a candidate set of microlensing events from the SuperMACHO survey and the efficiency with which the SuperMACHO project detects microlensing. The efficiency analysis is accomplished by simulating light curves over a spatial and temporal subset of the survey data. Assuming the optical depth observed by the MACHO project, we expect 14 microlensing events to pass our tighter set of selection criteria in this subset of data. Because type Ia supernovae remain a persistent contaminant in the SuperMACHO candidate set, this thesis also describes a method for determining the expected number of supernova contaminants in the SuperMACHO candidate set. We expect between 6 and 12 type Ia supernovae depending on which supernova rate

  20. Molecular characterization of norovirus GII.17 detected in healthy adult, intussusception patient, and acute gastroenteritis children in Thailand.

    PubMed

    Khamrin, Pattara; Kumthip, Kattareeya; Yodmeeklin, Arpaporn; Supadej, Kanittapon; Ukarapol, Nuthapong; Thongprachum, Aksara; Okitsu, Shoko; Hayakawa, Satoshi; Ushijima, Hiroshi; Maneekarn, Niwat

    2016-10-01

    Noroviruses (NoVs) have been recognized as a leading cause of sporadic cases and outbreaks of acute gastroenteritis in all age groups. During the surveillance of NoVs in Chiang Mai, Thailand, four cases of the novel GII.17 NoVs were sporadically detected by RT-PCR in 2014-2015. The first case of GII.17 was detected in a healthy adult who worked for a restaurant. The second case was found in a pediatric patient who admitted to the hospital with intussusception. The third and fourth cases were found in acute gastroenteritis children. Phylogenetic analysis clearly demonstrated that GII.17 NoVs detected in this study were genetically closely related with the novel GII.17 Kawasaki reference strains. These four GII.17 NoV positive specimens were also tested by two immunochromatographic test kits in order to evaluate the sensitivity for GII.17 NoV detection. The viral loads in those specimens were determined by real-time RT-PCR. The sensitivity of GII.17 NoV detection varies by individual test kits and also depending on the amount of the viruses contained in the fecal specimens. In summary, our study reported the detection of novel GII.17 NoVs in a wide range of subjects with and without diarrhea. Therefore, continued comprehensive screening and genetic molecular characterization of NoV strains circulating in this area need to be further investigated. PMID:27469026

  1. Rise Time Perception and Detection of Syllable Stress in Adults with Developmental Dyslexia

    ERIC Educational Resources Information Center

    Leong, Victoria; Hamalainen, Jarmo; Soltesz, Fruzsina; Goswami, Usha

    2011-01-01

    Introduction: The perception of syllable stress has not been widely studied in developmental dyslexia, despite strong evidence for auditory rhythmic perceptual difficulties. Here we investigate the hypothesis that perception of sound rise time is related to the perception of syllable stress in adults with developmental dyslexia. Methods: A…

  2. Children with Autism Detect Targets at Very Rapid Presentation Rates with Similar Accuracy as Adults

    ERIC Educational Resources Information Center

    Hagmann, Carl Erick; Wyble, Bradley; Shea, Nicole; LeBlanc, Megan; Kates, Wendy R.; Russo, Natalie

    2016-01-01

    Enhanced perception may allow for visual search superiority by individuals with Autism Spectrum Disorder (ASD), but does it occur over time? We tested high-functioning children with ASD, typically developing (TD) children, and TD adults in two tasks at three presentation rates (50, 83.3, and 116.7 ms/item) using rapid serial visual presentation.…

  3. Model-order selection in Zernike polynomial expansion of corneal surfaces using the efficient detection criterion.

    PubMed

    Alkhaldi, Weaam; Iskander, D Robert; Zoubir, Abdelhak M

    2010-10-01

    Corneal-height data are typically measured with videokeratoscopes and modeled using a set of orthogonal Zernike polynomials. We address the estimation of the number of Zernike polynomials, which is formalized as a model-order selection problem in linear regression. Classical information-theoretic criteria tend to overestimate the corneal surface due to the weakness of their penalty functions, while bootstrap-based techniques tend to underestimate the surface or require extensive processing. In this paper, we propose to use the efficient detection criterion (EDC), which has the same general form of information-theoretic-based criteria, as an alternative to estimating the optimal number of Zernike polynomials. We first show, via simulations, that the EDC outperforms a large number of information-theoretic criteria and resampling-based techniques. We then illustrate that using the EDC for real corneas results in models that are in closer agreement with clinical expectations and provides means for distinguishing normal corneal surfaces from astigmatic and keratoconic surfaces.

  4. Optimal Time-Resource Allocation for Energy-Efficient Physical Activity Detection

    PubMed Central

    Thatte, Gautam; Li, Ming; Lee, Sangwon; Emken, B. Adar; Annavaram, Murali; Narayanan, Shrikanth; Spruijt-Metz, Donna; Mitra, Urbashi

    2011-01-01

    The optimal allocation of samples for physical activity detection in a wireless body area network for health-monitoring is considered. The number of biometric samples collected at the mobile device fusion center, from both device-internal and external Bluetooth heterogeneous sensors, is optimized to minimize the transmission power for a fixed number of samples, and to meet a performance requirement defined using the probability of misclassification between multiple hypotheses. A filter-based feature selection method determines an optimal feature set for classification, and a correlated Gaussian model is considered. Using experimental data from overweight adolescent subjects, it is found that allocating a greater proportion of samples to sensors which better discriminate between certain activity levels can result in either a lower probability of error or energy-savings ranging from 18% to 22%, in comparison to equal allocation of samples. The current activity of the subjects and the performance requirements do not significantly affect the optimal allocation, but employing personalized models results in improved energy-efficiency. As the number of samples is an integer, an exhaustive search to determine the optimal allocation is typical, but computationally expensive. To this end, an alternate, continuous-valued vector optimization is derived which yields approximately optimal allocations and can be implemented on the mobile fusion center due to its significantly lower complexity. PMID:21796237

  5. Detective quantum efficiency: a standard test to ensure optimal detector performance and low patient exposures

    NASA Astrophysics Data System (ADS)

    Escartin, Terenz R.; Nano, Tomi F.; Cunningham, Ian A.

    2016-03-01

    The detective quantum efficiency (DQE), expressed as a function of spatial frequency, describes the ability of an x-ray detector to produce high signal-to-noise ratio (SNR) images. While regulatory and scientific communities have used the DQE as a primary metric for optimizing detector design, the DQE is rarely used by end users to ensure high system performance is maintained. Of concern is that image quality varies across different systems for the same exposures with no current measures available to describe system performance. Therefore, here we conducted an initial DQE measurement survey of clinical x-ray systems using a DQE-testing instrument to identify their range of performance. Following laboratory validation, experiments revealed that the DQE of five different systems under the same exposure level (8.0 μGy) ranged from 0.36 to 0.75 at low spatial frequencies, and 0.02 to 0.4 at high spatial frequencies (3.5 cycles/mm). Furthermore, the DQE dropped substantially with decreasing detector exposure by a factor of up to 1.5x in the lowest spatial frequency, and a factor of 10x at 3.5 cycles/mm due to the effect of detector readout noise. It is concluded that DQE specifications in purchasing decisions, combined with periodic DQE testing, are important factors to ensure patients receive the health benefits of high-quality images for low x-ray exposures.

  6. Efficient interpretation algorithm for embedded Bragg gratings for damage detection in composites

    NASA Astrophysics Data System (ADS)

    Prabhugoud, Mohanraj; Peters, Kara J.

    2003-07-01

    The goal of a structural health monitoring system is to detect, locate, and identify damages in a structure during its lifetime. The concept of structural health monitoring is particularly important for fiber reinforced composites due to the complexity of the possible failure mechanisms. The goal of this work is to simulate the response of optical fiber Bragg grating sensors to multi-component loading for their implementation in structural health monitoring algorithms for composites. A simulation method is presented to determine the effects of axial, bending and shear loading on an embedded optical fiber Bragg grating sensor. The effect of fiber bending on the Bragg grating sensor is experimentally verified by embedding the sensor in a solid cone, clamped at the base and subjected to a point load at the apex. Next, a numerically efficient method to calculate the response of sensors embedded in a unidirectional composite is developed using both finite element analysis and optimal shear-lag theory and taking into account the above effects. The limitations of the optimal shear-lag theory are derived through comparison with the finite element results. The application of this method is demonstrated through a numerical example, simulating the response of sensors embedded in one fiber layer to a transverse crack.

  7. CHARACTERISING THE EOS SLOT-SCANNING SYSTEM WITH THE EFFECTIVE DETECTIVE QUANTUM EFFICIENCY.

    PubMed

    Clavel, A H; Monnin, P; Létang, J M; Verdun, F R; Darbon, A

    2016-06-01

    As opposed to the standard detective quantum efficiency (DQE), effective DQE (eDQE) is a figure of merit that allows comparing the performances of imaging systems in the presence of scatter rejection devices. The geometry of the EOS™ slot-scanning system is such that the detector is self-collimated and rejects scattered radiation. In this study, the EOS system was characterised using the eDQE in imaging conditions similar to those used in clinical practice: with phantoms of different widths placed in the X-ray beam, for various incident air kerma and tube voltages corresponding to the phantom thickness. Scatter fractions in EOS images were extremely low, around 2 % for all configurations. Maximum eDQE values spanned 9-14.8 % for a large range of air kerma at the detector plane from 0.01 to 1.34 µGy. These figures were obtained with non-optimised EOS setting but still over-performed most of the maximum eDQEs recently assessed for various computed radiology and digital radiology systems with antiscatter grids. PMID:26538617

  8. Set-up and methods for SiPM Photo-Detection Efficiency measurements

    NASA Astrophysics Data System (ADS)

    Zappalà, G.; Acerbi, F.; Ferri, A.; Gola, A.; Paternoster, G.; Zorzi, N.; Piemonte, C.

    2016-08-01

    In this work, a compact set-up and three different methods to measure the Photo-Detection Efficiency (PDE) of Silicon Photomultipliers (SiPMs) and Single-Photon Avalanche Diodes (SPADs) are presented. The methods, based on either continuous or pulsed light illumination, are discussed in detail and compared in terms of measurement precision and time. For the SiPM, these methods have the feature of minimizing the effect of both the primary and correlated noise on the PDE estimation. The PDE of SiPMs (produced at FBK, Trento, Italy) was measured in a range from UV to NIR, obtaining similar results with all the methods. Furthermore, the advantages of measuring, when possible, the PDE of SPADs (of the same technology and with the same layout of a single SiPM cell) instead of larger devices are also discussed and a direct comparison between measurement results is shown. Using a SPAD, it is possible to reduce the measurement complexity and uncertainty since the correlated noise sources are reduced with respect to the SiPM case.

  9. Spectrally efficient direct-detected OFDM transmission employing an iterative estimation and cancellation technique.

    PubMed

    Peng, Wei-Ren; Wu, Xiaoxia; Feng, Kai-Ming; Arbab, Vahid R; Shamee, Bishara; Yang, Jeng-Yuan; Christen, Louis C; Willner, Alan E; Chi, Sien

    2009-05-25

    We demonstrate a linearly field-modulated, direct-detected virtual SSB-OFDM (VSSB-OFDM) transmission with an RF tone placed at the edge of the signal band. By employing the iterative estimation and cancellation technique for the signal-signal beat interference (SSBI) at the receiver, our approach alleviates the need of the frequency gap, which is typically reserved for isolating the SSBI, and saves half the electrical bandwidth, thus being very spectrally efficient. We derive the theoretical model for the VSSB-OFDM system and detail the signal processing for the iterative approach conducted at the receiver. Possible limitations for this iterative approach are also given and discussed. We successfully transmit a 10 Gbps, 4-quadrature-amplitude-modulation (QAM) VSSB-OFDM signal through 340 km of uncompensated standard single mode fiber (SSMF) with almost no penalty. In addition, the simulated results show that the proposed scheme has an approximately 2 dB optical-signal-to-noise-ratio (OSNR) gain and has a better chromatic dispersion (CD) tolerance compared with the previous intensity-modulated SSB-OFDM system.

  10. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    PubMed

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF. PMID:24323770

  11. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    PubMed

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF.

  12. A New Paradigm of Technology-Enabled ‘Vital Signs’ for Early Detection of Health Change for Older Adults.

    PubMed

    Rantz, Marilyn J; Skubic, Marjorie; Popescu, Mihail; Galambos, Colleen; Koopman, Richelle J; Alexander, Gregory L; Phillips, Lorraine J; Musterman, Katy; Back, Jessica; Miller, Steven J

    2015-01-01

    Environmentally embedded (nonwearable) sensor technology is in continuous use in elder housing to monitor a new set of ‘vital signs' that continuously measure the functional status of older adults, detect potential changes in health or functional status, and alert healthcare providers for early recognition and treatment of those changes. Older adult participants' respiration, pulse, and restlessness are monitored as they sleep. Gait speed, stride length, and stride time are calculated daily, and automatically assess for increasing fall risk. Activity levels are summarized and graphically displayed for easy interpretation. Falls are detected when they occur and alerts are sent immediately to healthcare providers, so time to rescue may be reduced. Automated health alerts are sent to healthcare staff, based on continuously running algorithms applied to the sensor data, days and weeks before typical signs or symptoms are detected by the person, family members, or healthcare providers. Discovering these new functional status ‘vital signs', developing automated methods for interpreting them, and alerting others when changes occur have the potential to transform chronic illness management and facilitate aging in place through the end of life. Key findings of research in progress at the University of Missouri are discussed in this viewpoint article, as well as obstacles to widespread adoption.

  13. The Genetic Architecture of Arsenic Metabolism Efficiency:A SNP-Based Heritability Study of Bangladeshi Adults

    PubMed Central

    Gao, Jianjun; Tong, Lin; Argos, Maria; Bryan, Molly Scannell; Ahmed, Alauddin; Rakibuz-Zaman, Muhammad; Kibriya, Muhammad G.; Jasmine, Farzana; Slavkovich, Vesna; Graziano, Joseph H.

    2015-01-01

    , Jasmine F, Slavkovich V, Graziano JH, Ahsan H, Pierce BL. 2015. The genetic architecture of arsenic metabolism efficiency: a SNP-based heritability study of Bangladeshi adults. Environ Health Perspect 123:985–992; http://dx.doi.org/10.1289/ehp.1408909 PMID:25768001

  14. Large-sensitive-area superconducting nanowire single-photon detector at 850 nm with high detection efficiency.

    PubMed

    Li, Hao; Zhang, Lu; You, Lixing; Yang, Xiaoyan; Zhang, Weijun; Liu, Xiaoyu; Chen, Sijing; Wang, Zhen; Xie, Xiaoming

    2015-06-29

    Satellite-ground quantum communication requires single-photon detectors of 850-nm wavelength with both high detection efficiency and large sensitive area. We developed superconducting nanowire single-photon detectors (SNSPDs) on one-dimensional photonic crystals, which acted as optical cavities to enhance the optical absorption, with a sensitive-area diameter of 50 μm. The fabricated multimode fiber coupled NbN SNSPDs exhibited a maximum system detection efficiency (DE) of up to 82% and a DE of 78% at a dark count rate of 100 Hz at 850-nm wavelength as well as a system jitter of 105 ps. PMID:26191739

  15. Molecularly imprinted fluorescent hollow nanoparticles as sensors for rapid and efficient detection λ-cyhalothrin in environmental water.

    PubMed

    Wang, Jixiang; Qiu, Hao; Shen, Hongqiang; Pan, Jianming; Dai, Xiaohui; Yan, Yongsheng; Pan, Guoqing; Sellergren, Börje

    2016-11-15

    Molecularly imprinted fluorescent polymers have shown great promise in biological or chemical separations and detections, due to their high stability, selectivity and sensitivity. In this work, molecularly imprinted fluorescent hollow nanoparticles, which could rapidly and efficiently detect λ-cyhalothrin (a toxic insecticide) in water samples, was reported. The molecularly imprinted fluorescent sensor showed excellent sensitivity (the limit of detection low to 10.26nM), rapid detection rate (quantitative detection of λ-cyhalothrin within 8min), regeneration ability (maintaining good fluorescence properties after 8 cycling operation) and appreciable selectivity over several structural analogs. Moreover, the fluorescent sensor was further used to detect λ-cyhalothrin in real samples form the Beijing-Hangzhou Grand Canal Water. Despite the relatively complex components of the environmental water, the molecularly imprinted fluorescent hollow nanosensor still showed good recovery, clearly demonstrating the potential value of this smart sensor nanomaterial in environmental monitoring. PMID:27208472

  16. Effects of rainfall events on the occurrence and detection efficiency of viruses in river water impacted by combined sewer overflows.

    PubMed

    Hata, Akihiko; Katayama, Hiroyuki; Kojima, Keisuke; Sano, Shoichi; Kasuga, Ikuro; Kitajima, Masaaki; Furumai, Hiroaki

    2014-01-15

    Rainfall events can introduce large amount of microbial contaminants including human enteric viruses into surface water by intermittent discharges from combined sewer overflows (CSOs). The present study aimed to investigate the effect of rainfall events on viral loads in surface waters impacted by CSO and the reliability of molecular methods for detection of enteric viruses. The reliability of virus detection in the samples was assessed by using process controls for virus concentration, nucleic acid extraction and reverse transcription (RT)-quantitative PCR (qPCR) steps, which allowed accurate estimation of virus detection efficiencies. Recovery efficiencies of poliovirus in river water samples collected during rainfall events (<10%) were lower than those during dry weather conditions (>10%). The log10-transformed virus concentration efficiency was negatively correlated with suspended solid concentration (r(2)=0.86) that increased significantly during rainfall events. Efficiencies of DNA extraction and qPCR steps determined with adenovirus type 5 and a primer sharing control, respectively, were lower in dry weather. However, no clear relationship was observed between organic water quality parameters and efficiencies of these two steps. Observed concentrations of indigenous enteric adenoviruses, GII-noroviruses, enteroviruses, and Aichi viruses increased during rainfall events even though the virus concentration efficiency was presumed to be lower than in dry weather. The present study highlights the importance of using appropriate process controls to evaluate accurately the concentration of water borne enteric viruses in natural waters impacted by wastewater discharge, stormwater, and CSOs.

  17. Effects of rainfall events on the occurrence and detection efficiency of viruses in river water impacted by combined sewer overflows.

    PubMed

    Hata, Akihiko; Katayama, Hiroyuki; Kojima, Keisuke; Sano, Shoichi; Kasuga, Ikuro; Kitajima, Masaaki; Furumai, Hiroaki

    2014-01-15

    Rainfall events can introduce large amount of microbial contaminants including human enteric viruses into surface water by intermittent discharges from combined sewer overflows (CSOs). The present study aimed to investigate the effect of rainfall events on viral loads in surface waters impacted by CSO and the reliability of molecular methods for detection of enteric viruses. The reliability of virus detection in the samples was assessed by using process controls for virus concentration, nucleic acid extraction and reverse transcription (RT)-quantitative PCR (qPCR) steps, which allowed accurate estimation of virus detection efficiencies. Recovery efficiencies of poliovirus in river water samples collected during rainfall events (<10%) were lower than those during dry weather conditions (>10%). The log10-transformed virus concentration efficiency was negatively correlated with suspended solid concentration (r(2)=0.86) that increased significantly during rainfall events. Efficiencies of DNA extraction and qPCR steps determined with adenovirus type 5 and a primer sharing control, respectively, were lower in dry weather. However, no clear relationship was observed between organic water quality parameters and efficiencies of these two steps. Observed concentrations of indigenous enteric adenoviruses, GII-noroviruses, enteroviruses, and Aichi viruses increased during rainfall events even though the virus concentration efficiency was presumed to be lower than in dry weather. The present study highlights the importance of using appropriate process controls to evaluate accurately the concentration of water borne enteric viruses in natural waters impacted by wastewater discharge, stormwater, and CSOs. PMID:24064345

  18. Combined Detection of Serum IL-10, IL-17, and CXCL10 Predicts Acute Rejection Following Adult Liver Transplantation

    PubMed Central

    Kim, Nayoung; Yoon, Young-In; Yoo, Hyun Ju; Tak, Eunyoung; Ahn, Chul-Soo; Song, Gi-Won; Lee, Sung-Gyu; Hwang, Shin

    2016-01-01

    Discovery of non-invasive diagnostic and predictive biomarkers for acute rejection in liver transplant patients would help to ensure the preservation of liver function in the graft, eventually contributing to improved graft and patient survival. We evaluated selected cytokines and chemokines in the sera from liver transplant patients as potential biomarkers for acute rejection, and found that the combined detection of IL-10, IL-17, and CXCL10 at 1-2 weeks post-operation could predict acute rejection following adult liver transplantation with 97% specificity and 94% sensitivity. PMID:27498551

  19. Efficient extraction and detection of aromatic toxicants from crude oil and tar balls using multiple cyclodextrin derivatives.

    PubMed

    Serio, Nicole; Levine, Mindy

    2015-06-15

    Herein we report the efficient extraction of aromatic analytes from crude oil and tar balls using multiple cyclodextrin derivatives. The known propensity of the cyclodextrins to bind hydrophobic guests in their hydrophobic interiors enhanced the extraction of aromatic analytes from the oil layer to the aqueous layer, with methyl-β-cyclodextrin and β-cyclodextrin providing the most significant enhancement in extraction efficiencies of aromatic toxicants (69% aromatic toxicants in aqueous layer in the presence of methyl-β-cyclodextrin compared to 47% in cyclodextrin-free solution for tar ball oil extraction), and provide optimal tunability for developing efficient extraction systems. The cyclodextrin derivatives also promoted efficient energy transfer in the aqueous solutions, with up to 86% efficient energy transfer observed in the presence of γ-cyclodextrin compared to 50% in the absence of cyclodextrin for oil spill oil extraction. Together, this dual function extraction followed by detection system has potential in the development of environmental remediation systems.

  20. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XV; Appraisal of the Relationship between Tag Detection Efficiency at Bonneville Dam and the Precision of In-River Survival Estimates of Returning PIT-Tagged Chinook Salmon, 2000 Technical Report.

    SciTech Connect

    Perez-Comas, Joes A.; Skalski, John R.

    2000-07-01

    In the advent of the installation of a PIT-tag interrogation system in the Cascades Island fish ladder at Bonneville Dam, this report provides guidance on the anticipated precision of in-river survival estimates for returning adult salmonids, between Bonneville and Lower Granite dams, for various levels of system-wide adult detection probability at Bonneville Dam. Precision was characterized by the standard error of the survival estimates and the coefficient of variation of the survival estimates. The anticipated precision of in-river survival estimates for returning adult salmonids was directly proportional to the number of PIT-tagged smolts released and to the system-wide adult detection efficiency at Bonneville Dam, as well as to the in-river juvenile survival above Lower Granite Dam. Moreover, for a given release size and system-wide adult detection efficiency at Bonneville Dam, higher estuarine and marine survival rates also produced more precise survival estimates. With a system-wide detection probability of P{sub BA} = 1 at Bonneville Dam, the anticipated CVs for in-river survival estimate ranged between 9.4 and 20% with release sizes of 10,000 smolts. Moreover, if the system-wide adult detection efficiency at Bonneville Dam is less than maximum (i.e., P{sub BA} < 1), precision of CV {le} 20% could still be attained. For example, for releases of 10,000 PIT-tagged fish a CV of 20% in the estimates of in-river survival for returning adult salmon could be reach with system-wide detection probabilities of 0.2 {le} P{sub BA} {le} 0.6, depending on the tagging scenario.

  1. An efficient probe for rapid detection of cyanide in water at parts per billion levels and naked-eye detection of endogenous cyanide.

    PubMed

    Kumari, Namita; Jha, Satadru; Bhattacharya, Santanu

    2014-03-01

    A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the "naked-eye" detection of cyanide ions in water with a visual color change from red to yellow (Δλmax =80 nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for "in-field" experiments without requiring any sophisticated instruments. PMID:24449698

  2. An efficient probe for rapid detection of cyanide in water at parts per billion levels and naked-eye detection of endogenous cyanide.

    PubMed

    Kumari, Namita; Jha, Satadru; Bhattacharya, Santanu

    2014-03-01

    A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the "naked-eye" detection of cyanide ions in water with a visual color change from red to yellow (Δλmax =80 nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for "in-field" experiments without requiring any sophisticated instruments.

  3. Wavelet-based algorithm for auto-detection of daily living activities of older adults captured by multiple inertial measurement units (IMUs).

    PubMed

    Ayachi, Fouaz S; Nguyen, Hung P; Lavigne-Pelletier, Catherine; Goubault, Etienne; Boissy, Patrick; Duval, Christian

    2016-03-01

    A recent trend in human motion capture is the use of inertial measurement units (IMUs) for monitoring and performance evaluation of mobility in the natural living environment. Although the use of such systems have grown significantly, the development of methods and algorithms to process IMU data for clinical purposes is still limited. The aim of this work is to develop algorithms based on wavelet transform and discrete-time detection of events for the automatic segmentation of tasks related activities of daily living (ADL) from body worn IMUs. Seven healthy older adults (73  ±  4 years old) performed 10 ADL tasks in a simulated apartment during trials of different durations (3, 4, and 5 min). They wore a suit (Synertial UK Ltd IGS-180) comprised of 17 IMUs positioned strategically on body segments to capture full body motion. The proposed method automatically detected the number of template waveforms (representing each movement separately) using discrete wavelet transform (DWT) and discrete-time detection of events based on angular velocity, linear acceleration and 3D orientation data of pertinent IMUs. The sensitivity (Se.) and specificity (Sp.) of detection for the proposed method was established using time stamps of10tasks obtained from visual segmentation of each trial using the video records and the avatar provided by the system's software. At first, we identified six pertinent sensors that were strongly associated to different activities (at most two sensors/task) that allowed detection of tasks with high accuracy. The proposed algorithm exhibited significant global accuracy (N events  =  1999, Se.  =  97.5%, Sp.  =  94%), despite the variation in the occurrences of the performed tasks (free living). The Se. varied from 94% to 100% for all the detected ADL tasks and Sp. ranged from 90% to 100% with the worst Sp.  =  85 and 87% for Release_mid (reaching for object held just beyond reach at chest height) and Turning

  4. A novel EPID design for enhanced contrast and detective quantum efficiency

    NASA Astrophysics Data System (ADS)

    Rottmann, Joerg; Morf, Daniel; Fueglistaller, Rony; Zentai, George; Star-Lack, Josh; Berbeco, Ross

    2016-09-01

    Beams-eye-view imaging applications such as real-time soft-tissue motion estimation are hindered by the inherently low image contrast of electronic portal imaging devices (EPID) currently available for clinical use. We introduce and characterize a novel EPID design that provides substantially increased detective quantum efficiency (DQE), contrast-to-noise ratio (CNR) and sensitivity without degradation in spatial resolution. The prototype design features a stack of four conventional EPID layers combined with low noise integrated readout electronics. Each layer consists of a copper plate, a scintillator (\\text{G}{{\\text{d}}2}{{\\text{O}}2}{{\\text{S}}{}}\\text{:Tb} ) and a photodiode/TFT-switch (aSi:H). We characterize the prototype’s signal response to a 6 MV photon beam in terms of modulation transfer function (MTF), DQE and CNR. The presampled MTF is estimated using a slanted slit technique, the DQE is calculated from measured normalized noise power spectra (nNPS) and the MTF and CNR is estimated using a Las Vegas contrast phantom. The prototype has been designed and built to be interchangeable with the current clinical EPID on the Varian TrueBeam platform (AS-1200) in terms of size and data output specifications. Performance evaluation is conducted in absolute values as well as in relative terms using the Varian AS-1200 EPID as a reference detector. A fivefold increase of DQE(0) to about 6.7% was observed by using the four-layered design versus the AS-1200 reference detector. No substantial differences are observed between each layer’s individual MTF and the one for all four layers operating combined indicating that defocusing due to beam divergence is negligible. Also, using four layers instead of one increases the signal to noise ratio by a factor of 1.7.

  5. Recovery efficiency and limit of detection of aerosolized Bacillus anthracis Sterne from environmental surface samples.

    PubMed

    Estill, Cheryl Fairfield; Baron, Paul A; Beard, Jeremy K; Hein, Misty J; Larsen, Lloyd D; Rose, Laura; Schaefer, Frank W; Noble-Wang, Judith; Hodges, Lisa; Lindquist, H D Alan; Deye, Gregory J; Arduino, Matthew J

    2009-07-01

    After the 2001 anthrax incidents, surface sampling techniques for biological agents were found to be inadequately validated, especially at low surface loadings. We aerosolized Bacillus anthracis Sterne spores within a chamber to achieve very low surface loading (ca. 3, 30, and 200 CFU per 100 cm(2)). Steel and carpet coupons seeded in the chamber were sampled with swab (103 cm(2)) or wipe or vacuum (929 cm(2)) surface sampling methods and analyzed at three laboratories. Agar settle plates (60 cm(2)) were the reference for determining recovery efficiency (RE). The minimum estimated surface concentrations to achieve a 95% response rate based on probit regression were 190, 15, and 44 CFU/100 cm(2) for sampling steel surfaces and 40, 9.2, and 28 CFU/100 cm(2) for sampling carpet surfaces with swab, wipe, and vacuum methods, respectively; however, these results should be cautiously interpreted because of high observed variability. Mean REs at the highest surface loading were 5.0%, 18%, and 3.7% on steel and 12%, 23%, and 4.7% on carpet for the swab, wipe, and vacuum methods, respectively. Precision (coefficient of variation) was poor at the lower surface concentrations but improved with increasing surface concentration. The best precision was obtained with wipe samples on carpet, achieving 38% at the highest surface concentration. The wipe sampling method detected B. anthracis at lower estimated surface concentrations and had higher RE and better precision than the other methods. These results may guide investigators to more meaningfully conduct environmental sampling, quantify contamination levels, and conduct risk assessment for humans.

  6. Gravitational waves from inspiralling compact binaries: Hexagonal template placement and its efficiency in detecting physical signals

    SciTech Connect

    Cokelaer, T.

    2007-11-15

    Matched filtering is used to search for gravitational waves emitted by inspiralling compact binaries in data from the ground-based interferometers. One of the key aspects of the detection process is the design of a template bank that covers the astrophysically pertinent parameter space. In an earlier paper, we described a template bank that is based on a square lattice. Although robust, we showed that the square placement is overefficient, with the implication that it is computationally more demanding than required. In this paper, we present a template bank based on an hexagonal lattice, which size is reduced by 40% with respect to the proposed square placement. We describe the practical aspects of the hexagonal template bank implementation, its size, and computational cost. We have also performed exhaustive simulations to characterize its efficiency and safeness. We show that the bank is adequate to search for a wide variety of binary systems (primordial black holes, neutron stars, and stellar-mass black holes) and in data from both current detectors (initial LIGO, Virgo and GEO600) as well as future detectors (advanced LIGO and EGO). Remarkably, although our template bank placement uses a metric arising from a particular template family, namely, stationary phase approximation, we show that it can be used successfully with other template families (e.g., Pade resummation and effective one-body approximation). This quality of being effective for different template families makes the proposed bank suitable for a search that would use several of them in parallel (e.g., in a binary black hole search). The hexagonal template bank described in this paper is currently used to search for nonspinning inspiralling compact binaries in data from the Laser Interferometer Gravitational-Wave Observatory (LIGO)

  7. First detection of the larval chalkbrood disease pathogen Ascosphaera apis (Ascomycota: Eurotiomycetes: Ascosphaerales) in adult bumble bees.

    PubMed

    Maxfield-Taylor, Sarah A; Mujic, Alija B; Rao, Sujaya

    2015-01-01

    Fungi in the genus Ascosphaera (Ascomycota: Eurotiomycetes: Ascosphaerales) cause chalkbrood disease in larvae of bees. Here, we report the first-ever detection of the fungus in adult bumble bees that were raised in captivity for studies on colony development. Wild queens of Bombus griseocollis, B. nevadensis and B. vosnesenskii were collected and maintained for establishment of nests. Queens that died during rearing or that did not lay eggs within one month of capture were dissected, and tissues were examined microscopically for the presence of pathogens. Filamentous fungi that were detected were plated on artificial media containing broad spectrum antibiotics for isolation and identification. Based on morphological characters, the fungus was identified as Ascosphaera apis (Maasen ex Claussen) Olive and Spiltoir, a species that has been reported earlier only from larvae of the European honey bee, Apis mellifera, the Asian honey bee, Apis cerana, and the carpenter bee Xylocopa californica arizonensis. The identity of the fungus was confirmed using molecular markers and phylogenetic analysis. Ascosphaera apis was detected in queens of all three bumble bee species examined. Of 150 queens dissected, 12 (8%) contained vegetative and reproductive stages of the fungus. Both fungal stages were also detected in two workers collected from colonies with Ascosphaera-infected B. nevadensis queens. In this study, wild bees could have been infected prior to capture for rearing, or, the A. apis infection could have originated via contaminated European honey bee pollen fed to the bumble bees in captivity. Thus, the discovery of A. apis in adult bumble bees in the current study has important implications for commercial production of bumble bee colonies and highlights potential risks to native bees via pathogen spillover from infected bees and infected pollen.

  8. First Detection of the Larval Chalkbrood Disease Pathogen Ascosphaera apis (Ascomycota: Eurotiomycetes: Ascosphaerales) in Adult Bumble Bees

    PubMed Central

    Maxfield-Taylor, Sarah A.; Mujic, Alija B.; Rao, Sujaya

    2015-01-01

    Fungi in the genus Ascosphaera (Ascomycota: Eurotiomycetes: Ascosphaerales) cause chalkbrood disease in larvae of bees. Here, we report the first-ever detection of the fungus in adult bumble bees that were raised in captivity for studies on colony development. Wild queens of Bombus griseocollis, B. nevadensis and B. vosnesenskii were collected and maintained for establishment of nests. Queens that died during rearing or that did not lay eggs within one month of capture were dissected, and tissues were examined microscopically for the presence of pathogens. Filamentous fungi that were detected were plated on artificial media containing broad spectrum antibiotics for isolation and identification. Based on morphological characters, the fungus was identified as Ascosphaera apis (Maasen ex Claussen) Olive and Spiltoir, a species that has been reported earlier only from larvae of the European honey bee, Apis mellifera, the Asian honey bee, Apis cerana, and the carpenter bee Xylocopa californica arizonensis. The identity of the fungus was confirmed using molecular markers and phylogenetic analysis. Ascosphaera apis was detected in queens of all three bumble bee species examined. Of 150 queens dissected, 12 (8%) contained vegetative and reproductive stages of the fungus. Both fungal stages were also detected in two workers collected from colonies with Ascosphaera-infected B. nevadensis queens. In this study, wild bees could have been infected prior to capture for rearing, or, the A. apis infection could have originated via contaminated European honey bee pollen fed to the bumble bees in captivity. Thus, the discovery of A. apis in adult bumble bees in the current study has important implications for commercial production of bumble bee colonies and highlights potential risks to native bees via pathogen spillover from infected bees and infected pollen. PMID:25885679

  9. Effort and Potential Efficiencies for Aquatic Non-native Species Early Detection

    EPA Science Inventory

    This manuscript is based on the early aquatic non-native species detection research in the Duluth-Superior harbor. The problem of early detection is essentially that of a "needle in a haystack" - to detect a newly arrived and presumably rare non-native species with a high probabi...

  10. Beta particle detection efficiency of the radiation sensor made from a mixture of polyaniline and titanium oxide

    NASA Astrophysics Data System (ADS)

    Tamura, M.; Miyata, H.; Katsumata, M.; Matsuda, K.; Ueno, T.; Ito, D.; Suzuki, T.

    2016-08-01

    We developed a new real-time radiation sensor using an organic semiconductor and measured its β-particle detection sensitivity. This sensor is fabricated by simply combining a p-type semiconductor, polyaniline (Pani), with an n-type semiconductor, TiO2, and processing the compound. Since Pani and TiO2 are both inexpensive materials, the sensor can be fabricated at a lower cost than inorganic semiconductor sensors. The signal of each fabricated sensor was measured by a charge sensitive ADC for the irradiation of β-particles. The response signal data of the ADC for each irradiation was measured to calculate the detection efficiency of the detector. The maximum detection efficiency measured as β-particle sensitivity of the sensor was 1%. This β-particle sensitivity is higher than that reported of Pani sensors in the past.

  11. Simulated Source and Flash Detection Efficiency during the Deep Convective Clouds and Chemistry Field Campaign Using a New Interactive Tool.

    NASA Astrophysics Data System (ADS)

    Chmielewski, V.; Bruning, E. C.

    2015-12-01

    Detailed source and flash detection efficiencies for Lightning Mapping Arrays (LMA) are needed for observational and climatological work with the data. Simulations of the LMAs active during the Deep Convective Clouds and Chemistry campaign (DC3) were performed with a new Monte Carlo interactive tool. As with previous simulations, it propagated emissions from a given source point, added Gaussian observed timing errors to the retrieval times at each station and used a least squared algorithm to find the best solution for the source. This simulation added the ability to account for variable receiver thresholds to restrict the stations contributing to the solution based on received power, which allowed a better examination of the overall impacts of site selection. The average errors were then calculated as has been done previously but with the addition of the probability of detection for a given source location. Based on a 17 month climatology of flashes over the West Texas Lightning Mapping Array (WTLMA), the distribution of flashes by number of sources was used to relate the source detection efficiency from the simulation to the most likely flash detection efficiency. As observed in previous theoretical and observational studies, the average errors in azimuth, range and especially altitude of the source point solutions increased with increasing distance from the center of the network, with the standard deviations of these errors highly dependent on the station configuration and noise thresholds. The source and therefore flash detection efficiency also decreased with range as expected, but its centroid was offset from the center of the WTLMA when variable, observed receiver thresholds were used instead of uniform thresholds across the network. With the observed WTLMA thresholds, 95% of flashes could be detected to approximately 150 km from the center of the network, where average altitude errors were less than 0.4 km but the standard deviation of those errors

  12. Optical recording of neuronal spiking activity from unbiased populations of neurons with high spike detection efficiency and high temporal precision.

    PubMed

    Ranganathan, Gayathri N; Koester, Helmut J

    2010-09-01

    Activity in populations of neurons is essential for cortical function including signaling of information and signal transport. Previous methods have made advances in recording activity from many neurons but have both technical and analytical limitations. Here we present an optical method, dithered random-access functional calcium imaging, to record somatic calcium signals from up to 100 neurons, in vitro and in vivo. We further developed a maximum-likelihood deconvolution algorithm to detect spikes and precise spike timings from the recorded calcium fluorescence signals. Spike detection efficiency and spike timing detection was determined in acute slices of juvenile mice. The results indicate that the combination of the two methods detected precise spiking activity from unbiased and spatially distributed populations of neurons in acute slices with high efficiency of spike detection (>97%), low rate of false positives (0.0023 spikes/s), and high temporal precision. The results further indicate that there is only a small window of excitation intensities where high spike detection can be achieved consistently.

  13. Plate-specific gain map correction for the improvement of detective quantum efficiency in computed radiography

    SciTech Connect

    Schnell, Erich A.; Samei, Ehsan; Dobbins, James T.

    2012-03-15

    Purpose: The purpose of this work is to improve the noise power spectrum (NPS), and thus the detective quantum efficiency (DQE), of computed radiography (CR) images by correcting for spatial gain variations specific to individual imaging plates. CR devices have not traditionally employed gain-map corrections, unlike the case with flat-panel detectors, because of the multiplicity of plates used with each reader. The lack of gain-map correction has limited the DQE(f) at higher exposures with CR. This current work describes a feasible solution to generating plate-specific gain maps. Methods: Ten high-exposure open field images were taken with an RQA5 spectrum, using a sixth generation CR plate suspended in air without a cassette. Image values were converted to exposure, the plates registered using fiducial dots on the plate, the ten images averaged, and then high-pass filtered to remove low frequency contributions from field inhomogeneity. A gain-map was then produced by converting all pixel values in the average into fractions with mean of one. The resultant gain-map of the plate was used to normalize subsequent single images to correct for spatial gain fluctuation. To validate performance, the normalized NPS (NNPS) for all images was calculated both with and without the gain-map correction. Variations in the quality of correction due to exposure levels, beam voltage/spectrum, CR reader used, and registration were investigated. Results: The NNPS with plate-specific gain-map correction showed improvement over the noncorrected case over the range of frequencies from 0.15 to 2.5 mm{sup -1}. At high exposure (40 mR), NNPS was 50%-90% better with gain-map correction than without. A small further improvement in NNPS was seen from carefully registering the gain-map with subsequent images using small fiducial dots, because of slight misregistration during scanning. Further improvement was seen in the NNPS from scaling the gain map about the mean to account for different beam

  14. Detection, characterization, and spontaneous differentiation in vitro of very small embryonic-like putative stem cells in adult mammalian ovary.

    PubMed

    Parte, Seema; Bhartiya, Deepa; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-08-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1-3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4-7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase-polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial-mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals.

  15. Efficient generation of integration-free ips cells from human adult peripheral blood using BCL-XL together with Yamanaka factors.

    PubMed

    Su, Rui-Jun; Baylink, David J; Neises, Amanda; Kiroyan, Jason B; Meng, Xianmei; Payne, Kimberly J; Tschudy-Seney, Benjamin; Duan, Yuyou; Appleby, Nancy; Kearns-Jonker, Mary; Gridley, Daila S; Wang, Jun; Lau, K-H William; Zhang, Xiao-Bing

    2013-01-01

    The ability to efficiently generate integration-free induced pluripotent stem cells (iPSCs) from the most readily available source-peripheral blood-has the potential to expedite the advances of iPSC-based therapies. We have successfully generated integration-free iPSCs from cord blood (CB) CD34(+) cells with improved oriP/EBNA1-based episomal vectors (EV) using a strong spleen focus forming virus (SFFV) long terminal repeat (LTR) promoter. Here we show that Yamanaka factors (OCT4, SOX2, MYC, and KLF4)-expressing EV can also reprogram adult peripheral blood mononuclear cells (PBMNCs) into pluripotency, yet at a very low efficiency. We found that inclusion of BCL-XL increases the reprogramming efficiency by approximately 10-fold. Furthermore, culture of CD3(-)/CD19(-) cells or T/B cell-depleted MNCs for 4-6 days led to the generation of 20-30 iPSC colonies from 1 ml PB, an efficiency that is substantially higher than previously reported. PB iPSCs express pluripotency markers, form teratomas, and can be induced to differentiate in vitro into mesenchymal stem cells, cardiomyocytes, and hepatocytes. Used together, our optimized factor combination and reprogramming strategy lead to efficient generation of integration-free iPSCs from adult PB. This discovery has potential applications in iPSC banking, disease modeling and regenerative medicine.

  16. Measurement and simulation of the neutron response and detection efficiency of a Pb-scintillating fiber calorimeter

    NASA Astrophysics Data System (ADS)

    Anelli, M.; Battistoni, G.; Bertolucci, S.; Bini, C.; Branchini, P.; Curceanu, C.; De Zorzi, G.; Di Domenico, A.; Di Micco, B.; Ferrari, A.; Gauzzi, P.; Giovannella, S.; Happacher, F.; Iliescu, M.; Martini, M.; Miscetti, S.; Nguyen, F.; Passeri, A.; Prokofiev, A.; Sala, P.; Sciascia, B.; Sirghi, F.

    2007-10-01

    The overall detection efficiency to neutrons of a small prototype of the KLOE Pb-scintillating fiber calorimeter has been measured at the neutron beam facility of The Svedberg Laboratory, TSL, Uppsala, in the kinetic energy range 5-175 MeV. The measurement of the neutron detection efficiency of a NE110 scintillator provided a reference calibration. At the lowest trigger threshold, the overall calorimeter efficiency ranges from 40% to 50%. This value largely exceeds the estimated 8-16% expected if the response were proportional only to the scintillator equivalent thickness. A detailed simulation of the calorimeter and of the TSL beamline has been performed with the FLUKA Monte Carlo code. The simulated response of the detector to neutrons is presented, as well as a first data-Monte Carlo comparison. The results show an overall neutron efficiency of about 50%, when no trigger threshold is applied. The reasons of such an efficiency enhancement, in comparison with the typical scintillator-based neutron counters, are explained, opening the road to a novel neutron detector.

  17. High Blood Cholesterol in Adults. Report of the Expert Panel on Detection, Evaluation, and Treatment.

    ERIC Educational Resources Information Center

    National Heart, Lung, and Blood Inst. (DHHS/NIH), Bethesda, MD.

    This report offers a patient-based approach to lowering blood cholesterol levels which seeks to identify individuals at high risk who will benefit from intensive intervention efforts. The goal is to establish criteria that define the candidates for medical intervention and to provide guidelines on how to detect, set goals for, treat, and monitor…

  18. Visual detection technique for efficient screening and isolation of Salmonella based on a novel enrichment assay using chromatography membrane.

    PubMed

    Tang, F; Xiong, Y; Zhang, H; Wu, K; Xiang, Y; Shao, J-B; Ai, H-W; Xiang, Y-P; Zheng, X-L; Lv, J-R; Sun, H; Bao, L-S; Zhang, Z; Hu, H-B; Zhang, J-Y; Chen, L; Lu, J; Liu, W-Y; Mei, H; Ma, Y; Xu, C-F; Fang, A-Y; Gu, M; Xu, C-Y; Chen, Y; Chen, Z; Sun, Z-Y

    2016-03-01

    To detect Salmonella more efficiently and isolate strains more easily, a novel and simple detection method that uses an enrichment assay and two chromogenic reactions on a chromatography membrane was developed. Grade 3 chromatography paper is used as functionalized solid phase support (SPS), which contains specially optimized medium. One reaction for screening is based on the sulfate-reducing capacity of Salmonella. Hydrogen sulfide (H2S) generated by Salmonella reacts with ammonium ferric citrate to produce black colored ferrous sulfide. Another reaction is based on Salmonella C8 esterase that is unique for Enterobacteriaceae except Serratia and interacts with 4-methylumbelliferyl caprylate (MUCAP) to produce fluorescent umbelliferone, which is visible under ultraviolet light. A very low detection limit (10(1) CFU ml(-1)) for Salmonella was achieved on the background of 10(5) CFU ml(-1) Escherichia coli. More importantly, testing with more than 1,000 anal samples indicated that our method has a high positive detection rate and is relatively low cost, compared with the traditional culture-based method. It took only 1 day for the preliminary screening and 2 days to efficiently isolate the Salmonella cells, indicating that the new assay is specific, rapid, and simple for Salmonella detection. In contrast to the traditional culture-based method, this method can be easily used to screen and isolate targeted strains with the naked eye. The results of quantitative and comparative experiments showed that the visual detection technique is an efficient alternative method for the screening of Salmonella spp. in many applications of large-sized samples related to public health surveillance. PMID:26796551

  19. Visual detection technique for efficient screening and isolation of Salmonella based on a novel enrichment assay using chromatography membrane.

    PubMed

    Tang, F; Xiong, Y; Zhang, H; Wu, K; Xiang, Y; Shao, J-B; Ai, H-W; Xiang, Y-P; Zheng, X-L; Lv, J-R; Sun, H; Bao, L-S; Zhang, Z; Hu, H-B; Zhang, J-Y; Chen, L; Lu, J; Liu, W-Y; Mei, H; Ma, Y; Xu, C-F; Fang, A-Y; Gu, M; Xu, C-Y; Chen, Y; Chen, Z; Sun, Z-Y

    2016-03-01

    To detect Salmonella more efficiently and isolate strains more easily, a novel and simple detection method that uses an enrichment assay and two chromogenic reactions on a chromatography membrane was developed. Grade 3 chromatography paper is used as functionalized solid phase support (SPS), which contains specially optimized medium. One reaction for screening is based on the sulfate-reducing capacity of Salmonella. Hydrogen sulfide (H2S) generated by Salmonella reacts with ammonium ferric citrate to produce black colored ferrous sulfide. Another reaction is based on Salmonella C8 esterase that is unique for Enterobacteriaceae except Serratia and interacts with 4-methylumbelliferyl caprylate (MUCAP) to produce fluorescent umbelliferone, which is visible under ultraviolet light. A very low detection limit (10(1) CFU ml(-1)) for Salmonella was achieved on the background of 10(5) CFU ml(-1) Escherichia coli. More importantly, testing with more than 1,000 anal samples indicated that our method has a high positive detection rate and is relatively low cost, compared with the traditional culture-based method. It took only 1 day for the preliminary screening and 2 days to efficiently isolate the Salmonella cells, indicating that the new assay is specific, rapid, and simple for Salmonella detection. In contrast to the traditional culture-based method, this method can be easily used to screen and isolate targeted strains with the naked eye. The results of quantitative and comparative experiments showed that the visual detection technique is an efficient alternative method for the screening of Salmonella spp. in many applications of large-sized samples related to public health surveillance.

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

    PubMed

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

    2016-01-01

    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. PMID:26907295

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

    PubMed Central

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

    2016-01-01

    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. PMID:26907295

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

    PubMed

    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.

  3. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV.

  4. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. PMID:26773821

  5. Spectrally efficient terabit optical transmission with Nyquist 64-QAM half-cycle subcarrier modulation and direct detection.

    PubMed

    Zou, Kaiheng; Zhu, Yixiao; Zhang, Fan; Chen, Zhangyuan

    2016-06-15

    We demonstrate 1.728  Tb/s(16×108  Gb/s) direct-detection wavelength division multiplexing (WDM) transmission over 80 km standard single mode fiber (SSMF) with Nyquist 64-ary quadrature amplitude modulation (64-QAM) and half-cycle subcarrier modulation. Each channel carries single sideband 18 GBaud 64-QAM signal and the channel spacing is 27 GHz. Considering 20% soft-decision forward error correction and frame redundancy, a net spectral efficiency record of 3.25 b/s/Hz is achieved for 100 G single polarization direct-detection WDM transmission.

  6. The significance of clinical practice guidelines on adult varicocele detection and management

    PubMed Central

    Shridharani, Anand; Owen, Ryan C; Elkelany, Osama O; Kim, Edward D

    2016-01-01

    Varicoceles are the most common correctable etiology of male factor infertility. However, the detection and management of varicoceles have not been standardized. This has led to decades of debate regarding the effect of varicocele on male infertility and subsequently whether repair leads to an improved fertility status. The current body of evidence investigating the role of varicocele and varicocelectomy is weak and conflicting. The stance taken by the AUA and ASRM suggests that there is insufficient outcomes data to support evidenced-based guidelines, citing evidence used to provide current recommendations are generally of a low quality level. On the other hand, the EAU Guidelines give a level 1a of evidence for management of varicoceles that are clinically palpable, associated with subnormal semen analyses and having otherwise unexplained fertility. Besides aiding with clinical varicocele detection and management, clinical practice opinion statements and guidelines aim to direct and strengthen the infrastructure of future studies. We review the current status of opinion statements and guidelines in varicocele and management detection with focus on their application in practice. PMID:26806081

  7. Cycle Slips Detection in Quad-Frequency Mode: Galileo's Contribution to an Efficient Approach under High Ionospheric Activity

    NASA Astrophysics Data System (ADS)

    Van de Vyvere, Laura; Warnant, René

    2016-04-01

    Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available in Open Service, we were able to develop an innovative detection algorithm, especially promising in harsh environment like high ionospheric activity. This improves previous dual and triple-frequency methods, whose efficiency was somehow limited in tricky situations, like ionospheric events or particular configurations. In our algorithm, two types of testing quantities were used: triple-frequency Simsky combination and dual-frequency Geometry-Free combination, each one being associated to a suitable detection algorithm. Simsky combination allows to detect almost every configuration, except for cycle slips of the same magnitude, appearing simultaneously on all carriers. Geometry-Free combination is only used to detect this particular case, since it suffers from quick variation of ionospheric delay. Together - through the choice of the most efficient combination alternatives - they enable the detection of any cycle slips configuration. This is now made possible thanks to the availability of data from Galileo's four carriers. The quad-frequency algorithm has been tested on Galileo observations from both GMSD (Japan) and NKLG (Gabon) stations. On the first ones, cycle slips were artificially inserted in order to simulate particular cases and test algorithm robustness. NKLG raw data were used to assess algorithm behaviour for cases met in the equatorial area. Enhanced with a suitable cycle slip correction method and a real-time feature, our algorithm could directly be integrated into the software receiver, enabling the supply of continuous and corrected data to the user. In conclusion, this first quad-frequency cycle slips detection algorithm is obviously a step forward and every Galileo user will indeed be able to benefit from a highly better-quality positioning. With

  8. Highly efficient SERS-based detection of cerebrospinal fluid neopterin as a diagnostic marker of bacterial infection.

    PubMed

    Kamińska, Agnieszka; Witkowska, Evelin; Kowalska, Aneta; Skoczyńska, Anna; Gawryszewska, Iwona; Guziewicz, Elżbieta; Snigurenko, Dymitr; Waluk, Jacek

    2016-06-01

    A highly efficient recognition unit based on surface-enhanced Raman spectroscopy (SERS) was developed as a promising, fast, and sensitive tool for detection of meningococcal meningitis, which is an extremely serious and often fatal disease of the nervous system (an inflammation of the lining around the brain and spinal cord). The results of this study confirmed that there were specific differences in SERS spectra between cerebrospinal fluid (CSF) samples infected by Neisseria meningitidis and the normal CSF, suggesting a potential role for neopterin in meningococcal meningitis detection and screening applications. To estimate the best performance of neopterin as a marker of bacterial infection, principal component analysis (PCA) was performed in a selected region (640-720 cm(-1)) where the most prominent SERS peak at 695 cm(-1) arising from neopterin was observed. The calculated specificity of 95 % and sensitivity of 98 % clearly indicate the effective diagnostic efficiency for differentiation between infected and control samples. Additionally, the limit of detection (LOD) of neopterin in CSF clinical samples was estimated. The level of neopterin was significantly higher in CSF samples infected by N. meningitidis (48 nmol/L), compared to the normal (control) group (4.3 nmol/L). Additionally, this work presents a new type of SERS-active nanostructure, based on polymer mats, that allows simultaneous filtration, immobilization, and enhancement of the Raman signal, enabling detection of spectra from single bacterial cells of N. meningitidis present in CSF samples. This provides a new possibility for fast and easy detection of bacteria in CSF and other clinical body fluids on a time scale of seconds. This method of detection produces consistent results faster and cheaper than traditional laboratory techniques, demonstrates the powerful potential of SERS for detection of disease, and shows the viability of future development in healthcare applications. PMID

  9. Nyquist-shaped dispersion-precompensated subcarrier modulation with direct detection for spectrally-efficient WDM transmission.

    PubMed

    Erkılınç, M S; Kilmurray, S; Maher, R; Paskov, M; Bouziane, R; Pachnicke, S; Griesser, H; Thomsen, B C; Bayvel, P; Killey, R I

    2014-04-21

    The use of single-sideband subcarrier modulation (SCM) with Nyquist (N) pulse shaping for cost-effective spectrally-efficient wavelength division multiplexed transmission with direct detection is described. Transmission of digitally pre-compensated 7 × 11 GHz-spaced QPSK SCM channels at 14 Gb/s per channel is experimentally demonstrated over distances of up to 800 km of uncompensated standard single-mode fiber (SSMF) (13440 ps/nm chromatic dispersion).

  10. Detection of Urinary Tract Pathology in Some Schistosoma haematobium Infected Nigerian Adults.

    PubMed

    Onile, O S; Awobode, H O; Oladele, V S; Agunloye, A M; Anumudu, C I

    2016-01-01

    Screening for Schistosoma haematobium infection and its possible morbidity was carried out in 257 adult participants in Eggua community, Ogun State, Nigeria. Parasitological assessment for the presence of ova of S. haematobium in urine and abdominopelvic ultrasonographic examination for bladder and secondary kidney pathology were carried out. S. haematobium prevalence of 25.68% (66/257) was recorded among the participants. There was a significantly higher prevalence of 69.2% of urinary schistosomiasis in the females than the prevalence of 31.8% in males (P = 0.902). The intensity of infections was mostly light (55) (21.8%) compared to heavy (10) (3.9%) with the mean intensity of 16.7 eggs/10 mL urine. Structural bladder pathology prevalence among participants was 33.9%. The bladder and kidney pathologies observed by ultrasound in subjects with S. haematobium infections included abnormal bladder wall thickness (59%), abnormal bladder shape (15.2%), bladder wall irregularities (15.2%), bladder masses (1.5%), bladder calcification (1.5%), and hydronephrosis (3%). Infection with S. haematobium was associated with bladder pathology. Higher frequencies of bladder abnormalities were observed more in the participants with light intensity of S. haematobium infection than in those with heavy infection. More bladder pathology was also seen in women than in men, although this was not statistically significant. In conclusion, there is evidence that the development of bladder pathology may be associated with S. haematobium infection. PMID:27635146

  11. Detecting Superior Face Recognition Skills in a Large Sample of Young British Adults

    PubMed Central

    Bobak, Anna K.; Pampoulov, Philip; Bate, Sarah

    2016-01-01

    The Cambridge Face Memory Test Long Form (CFMT+) and Cambridge Face Perception Test (CFPT) are typically used to assess the face processing ability of individuals who believe they have superior face recognition skills. Previous large-scale studies have presented norms for the CFPT but not the CFMT+. However, previous research has also highlighted the necessity for establishing country-specific norms for these tests, indicating that norming data is required for both tests using young British adults. The current study addressed this issue in 254 British participants. In addition to providing the first norm for performance on the CFMT+ in any large sample, we also report the first UK specific cut-off for superior face recognition on the CFPT. Further analyses identified a small advantage for females on both tests, and only small associations between objective face recognition skills and self-report measures. A secondary aim of the study was to examine the relationship between trait or social anxiety and face processing ability, and no associations were noted. The implications of these findings for the classification of super-recognizers are discussed. PMID:27713706

  12. Serological and virological detection of canine herpesvirus-1 in adult dogs with and without reproductive disorders.

    PubMed

    Pratelli, A; Colao, V; Losurdo, M

    2014-05-01

    Canine herpesvirus 1 (CaHV-1) is known to cause reproductive disorders in adult dogs and neonatal mortality in puppies. The seroprevalence of CaHV-1 has not been documented in Italy. Sera from 865 dogs were screened for CaHV-1 using a serum neutralization assay (SN). All CaHV-1 positive sera and 100 CaHV-1 negative sera were also tested using an in-house immunofluorescence (IF) test. Thirteen bitches with reproductive disorders and three bitches with no history of reproductive diseases were also examined clinically so that lesions associated with CaHV-1 and CaHV-1 DNA could be identified using PCR analysis of vaginal swabs. An overall seroprevalence of 14.6% was observed using SN, and 18.6% using IF. The correlation between SN and IF was moderate. The SN assay demonstrated a greater sensitivity than IF, with a few exceptions. None of the vaginal swabs tested positive for CaHV-1 DNA. The differences in the seropositivity rates between SN and IF were not statistically significant (P = 0.16). Using the SN test as the reference standard, the sensitivity and specificity of IF were 29% and 95%, respectively. These results suggest that CaHV-1 is common in canine populations and could pose a threat to neonatal survival and canine fertility in breeding kennels in Italy. Vaccination of breeding bitches should be recommended if there is a history of reproductive disorders.

  13. Detection of Growth Hormone Deficiency in Adults with Chronic Traumatic Brain Injury

    PubMed Central

    Griesbach, Grace S.; Ashley, Mark J.

    2016-01-01

    Abstract This study examined the prevalence of growth hormone deficiency (GHD) in patients with traumatic brain injury (TBI) during the post-acute phase of recovery and whether GHD was associated with increased disability, decreased independence, and depression. A secondary objective was to determine the accuracy of insulin-like growth factor-1 (IGF-1) levels in predicting GHD in patients with TBI. Anterior pituitary function was assessed in 235 adult patients with TBI through evaluation of fasting morning hormone levels. GH levels were assessed through provocative testing, specifically the glucagon stimulation test. GHD was diagnosed in a significant number of patients, with 45% falling into the severe GHD (≤3 μg/L) category. IGF-1 levels were not predictive of GHD. Patients with GHD were more disabled and less independent compared with those patients who were not GHD. Those patients with more severe GHD also showed decreased levels of cortisol and testosterone. Symptoms of depression were also more prevalent in this group. In addition, patients with severe GHD had delayed admission to post-acute rehabilitation. This study confirms the high prevalence of GHD in patients with TBI and the necessity to monitor clinical symptoms and perform provocative testing to definitively diagnose GHD. PMID:26414093

  14. Detection of Urinary Tract Pathology in Some Schistosoma haematobium Infected Nigerian Adults

    PubMed Central

    Onile, O. S.; Awobode, H. O.; Oladele, V. S.; Agunloye, A. M.

    2016-01-01

    Screening for Schistosoma haematobium infection and its possible morbidity was carried out in 257 adult participants in Eggua community, Ogun State, Nigeria. Parasitological assessment for the presence of ova of S. haematobium in urine and abdominopelvic ultrasonographic examination for bladder and secondary kidney pathology were carried out. S. haematobium prevalence of 25.68% (66/257) was recorded among the participants. There was a significantly higher prevalence of 69.2% of urinary schistosomiasis in the females than the prevalence of 31.8% in males (P = 0.902). The intensity of infections was mostly light (55) (21.8%) compared to heavy (10) (3.9%) with the mean intensity of 16.7 eggs/10 mL urine. Structural bladder pathology prevalence among participants was 33.9%. The bladder and kidney pathologies observed by ultrasound in subjects with S. haematobium infections included abnormal bladder wall thickness (59%), abnormal bladder shape (15.2%), bladder wall irregularities (15.2%), bladder masses (1.5%), bladder calcification (1.5%), and hydronephrosis (3%). Infection with S. haematobium was associated with bladder pathology. Higher frequencies of bladder abnormalities were observed more in the participants with light intensity of S. haematobium infection than in those with heavy infection. More bladder pathology was also seen in women than in men, although this was not statistically significant. In conclusion, there is evidence that the development of bladder pathology may be associated with S. haematobium infection. PMID:27635146

  15. Detection of Urinary Tract Pathology in Some Schistosoma haematobium Infected Nigerian Adults

    PubMed Central

    Onile, O. S.; Awobode, H. O.; Oladele, V. S.; Agunloye, A. M.

    2016-01-01

    Screening for Schistosoma haematobium infection and its possible morbidity was carried out in 257 adult participants in Eggua community, Ogun State, Nigeria. Parasitological assessment for the presence of ova of S. haematobium in urine and abdominopelvic ultrasonographic examination for bladder and secondary kidney pathology were carried out. S. haematobium prevalence of 25.68% (66/257) was recorded among the participants. There was a significantly higher prevalence of 69.2% of urinary schistosomiasis in the females than the prevalence of 31.8% in males (P = 0.902). The intensity of infections was mostly light (55) (21.8%) compared to heavy (10) (3.9%) with the mean intensity of 16.7 eggs/10 mL urine. Structural bladder pathology prevalence among participants was 33.9%. The bladder and kidney pathologies observed by ultrasound in subjects with S. haematobium infections included abnormal bladder wall thickness (59%), abnormal bladder shape (15.2%), bladder wall irregularities (15.2%), bladder masses (1.5%), bladder calcification (1.5%), and hydronephrosis (3%). Infection with S. haematobium was associated with bladder pathology. Higher frequencies of bladder abnormalities were observed more in the participants with light intensity of S. haematobium infection than in those with heavy infection. More bladder pathology was also seen in women than in men, although this was not statistically significant. In conclusion, there is evidence that the development of bladder pathology may be associated with S. haematobium infection.

  16. Probabilistic monitoring in intrusion detection module for energy efficiency in mobile ad hoc networks

    NASA Astrophysics Data System (ADS)

    De Rango, Floriano; Lupia, Andrea

    2016-05-01

    MANETs allow mobile nodes communicating to each other using the wireless medium. A key aspect of these kind of networks is the security, because their setup is done without an infrastructure, so external nodes could interfere in the communication. Mobile nodes could be compromised, misbehaving during the multi-hop transmission of data, or they could have a selfish behavior to save energy, which is another important constraint in MANETs. The detection of these behaviors need a framework that takes into account the latest interactions among nodes, so malicious or selfish nodes could be detected also if their behavior is changed over time. The monitoring activity increases the energy consumption, so our proposal takes into account this issue reducing the energy required by the monitoring system, keeping the effectiveness of the intrusion detection system. The results show an improvement in the saved energy, improving the detection performance too.

  17. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XIV; Appraisal of the Relationship between Tag Detection Efficiency at Bonneville Dam and the Precision in Estuarine and Marine Survival Estimates on Returning PIT Tagged Chinook Salmon, 2000 Technical Report.

    SciTech Connect

    Perez-Comas, Jose A.; Skalski, John R.

    2000-07-01

    In the advent of the installation of a PIT-tag interrogation system in the Cascades Island fish ladder at Bonneville Dam, this report provides guidance on the anticipated precision of salmonid estuarine and marine survival estimates, for various levels of system-wide adult detection probability at Bonneville Dam. Precision was characterized by the standard error of the survival estimates and the coefficient of variation of the survival estimates. The anticipated precision of salmonid estuarine and marine survival estimates was directly proportional to the number of PIT-tagged smolts released and to the system-wide adult detection efficiency at Bonneville Dam, as well as to the in-river juvenile survival above Lower Granite Dam. Moreover, for a given release size and system-wide adult detection efficiency, higher estuarine and marine survivals did also produce more precise survival estimates. With a system-wide detection probability of P{sub BA} = 1 at Bonneville Dam, the anticipated CVs for the estuarine and marine survival ranged between 41 and 88% with release sizes of 10,000 smolts. Only with the 55,000 smolts being released from sites close to Lower Granite Dam and under high estuarine and marine survival, could CVs of 20% be attained with system detection efficiencies of less than perfect detection (i.e., P{sub BA} < 1).

  18. Cobalt phosphide nanowires: an efficient electrocatalyst for enzymeless hydrogen peroxide detection

    NASA Astrophysics Data System (ADS)

    Liu, Danni; Chen, Tao; Zhu, Wenxin; Cui, Liang; Asiri, Abdullah M.; Lu, Qun; Sun, Xuping

    2016-08-01

    In this letter, we demonstrate for the first time that cobalt phosphide nanowires (CoP NWs) exhibit remarkable catalytic activity toward electrochemical detection of hydrogen peroxide (H2O2). As an enzymeless H2O2 sensor, such CoP NWs show a fast amperometric response within 5 s and a low detection limit of 0.48 μM. In addition, this nonenzymatic sensor displays good selectivity, long-term stability and excellent reproducibility.

  19. High-efficiency scintillation detector for combined detection of thermal and fast neutrons and gamma radiation

    DOEpatents

    Chiles, M.M.; Mihalczo, J.T.; Blakeman, E.D.

    1987-02-27

    A scintillation based radiation detector for the combined detection of thermal neutrons, high-energy neutrons and gamma rays in a single detecting unit. The detector consists of a pair of scintillators sandwiched together and optically coupled to the light sensitive face of a photomultiplier tube. A light tight radiation pervious housing is disposed about the scintillators and a portion of the photomultiplier tube to hold the arrangement in assembly and provides a radiation window adjacent the outer scintillator through which the radiation to be detected enters the detector. The outer scintillator is formed of a material in which scintillations are produced by thermal-neutrons and the inner scintillator is formed of a material in which scintillations are produced by high-energy neutrons and gamma rays. The light pulses produced by events detected in both scintillators are coupled to the photomultiplier tube which produces a current pulse in response to each detected event. These current pulses may be processed in a conventional manner to produce a count rate output indicative of the total detected radiation event count rate. Pulse discrimination techniques may be used to distinguish the different radiations and their energy distribution.

  20. Mutations in mammalian tolloid-like 1 gene detected in adult patients with ASD

    PubMed Central

    Stańczak, Paweł; Witecka, Joanna; Szydło, Anna; Gutmajster, Ewa; Lisik, Małgorzata; Auguściak-Duma, Aleksandra; Tarnowski, Maciej; Czekaj, Tomasz; Czekaj, Hanna; Sieroń, Aleksander L

    2009-01-01

    Atrial septal defect (ASD) is an incomplete septation of atria in human heart causing circulatory problems. Its frequency is estimated at one per 10 000. Actions of numerous genes have been linked to heart development. However, no single gene defect causing ASD has yet been identified. Incomplete heart septation similar to ASD was reported in transgenic mice with both inactive alleles of gene encoding mammalian zinc metalloprotease a mammalian tolloid-like 1 (tll1). Here, we have screened 19 ASD patients and 15 healthy age-matched individuals for mutations in TLL1 gene. All 22 exons were analyzed exon by exon for heteroduplex formation. Subsequently, DNA fragments forming heteroduplexes were sequenced. In four nonrelated patients, three missense mutations in coding sequence, and one single base change in the 5′UTR have been detected. Two mutations (Met182Leu, and Ala238Val) were detected in ASD patients with the same clinical phenotype. As the second mutation locates immediately upstream of the catalytic zinc-binding signature, it might change the enzyme substrate specificity. The third change, Leu627Val in the CUB3 domain, has been found in an ASD patient with interatrial septum aneurysm in addition to ASD. The CUB3 domain is important for substrate-specific recognition. In the remaining 15 patients as well as in 15 reference samples numerous base substitutions, deletions, and insertions have been detected, but no mutations changing the coding sequence have been found. Lack of mutations in relation to ASD of these patients could possibly be because of genetic heterogeneity of the syndrome. PMID:18830233

  1. Predatory efficiency of the water bug Sphaerodema annulatum on mosquito larvae (Culex quinquefasciatus) and its effect on the adult emergence.

    PubMed

    Aditya, G; Bhattacharyya, S; Kundu, N; Saha, G K; Raut, S K

    2004-11-01

    The daily number of IV instar larva of Culex quinquefasciatus killed, rate of pupation and adult emergence was noted in presence of the predatory water bug Sphaerodema annulatum for a period of seven consecutive days, experimentally, in the laboratory. The rate of IV instar larva killed by the water bugs on an average was 65.17 per day. The rate of pupation ranged between 7.6 and 48 in control while in presence of water bugs it ranged between 6 and 35. The rate of adult emergence in control experiments varied between 1.4 and 4.8 per day, which was reduced to only 0.4-28.8 per day in case of the water bugs. The results clearly indicate that the water bugs on its way of predation reduces the rate of pupation and adult emergence of Cx. quinquefasciatus significantly which calls for an extensive field trials.

  2. A universal TaqMan-based RT-PCR protocol for cost-efficient detection of small noncoding RNA

    PubMed Central

    Jung, Ulrike; Jiang, Xiaoou; Kaufmann, Stefan H.E.; Patzel, Volker

    2013-01-01

    Several methods for the detection of RNA have been developed over time. For small RNA detection, a stem–loop reverse primer-based protocol relying on TaqMan RT-PCR has been described. This protocol requires an individual specific TaqMan probe for each target RNA and, hence, is highly cost-intensive for experiments with small sample sizes or large numbers of different samples. We describe a universal TaqMan-based probe protocol which can be used to detect any target sequence and demonstrate its applicability for the detection of endogenous as well as artificial eukaryotic and bacterial small RNAs. While the specific and the universal probe-based protocol showed the same sensitivity, the absolute sensitivity of detection was found to be more than 100-fold lower for both than previously reported. In subsequent experiments, we found previously unknown limitations intrinsic to the method affecting its feasibility in determination of mature template RISC incorporation as well as in multiplexing. Both protocols were equally specific in discriminating between correct and incorrect small RNA targets or between mature miRNA and its unprocessed RNA precursor, indicating the stem–loop RT-primer, but not the TaqMan probe, triggers target specificity. The presented universal TaqMan-based RT-PCR protocol represents a cost-efficient method for the detection of small RNAs. PMID:24149841

  3. Selection of more appropriate PCR primer pairs for improved efficiency in detecting Norwalk-like virus (NLV) RNA.

    PubMed

    Naitou, Hirotaka; Morita, Tamotsu

    2001-10-01

    A pair of primers, NV35 and NV36, and another pair of primers, NV81 and NV82/SM82, are commonly used for polymerase chain reaction (PCR) detection of Norwalk-like virus (NLV) genome RNA sequences in authorized test laboratories in Japan. However, the efficiency of NLV genome RNA detection with these primer pairs has been less than satisfactory. In the present study, we attempted to establish more appropriately matched primer pairs for improved detection of NLV genome RNA sequences using a combination of primers including NV35, NV36, NV81, NV82/SM82, SR33, and SRs (a mixture of 4 primers SR46, SR48, SR50, and SR52). We also evaluated appropriate primers for improved reverse transcription of NLV genome RNA. Stool samples used for detection of NLV included 18 samples collected from NLV-infected patients who ingested oysters (group 1) and 13 samples collected from those who did not ingest oysters (group 2). Reverse transcription of RNA genome with primer NV35 was less efficient compared with that with primer SR33 or NV81. When PCR products obtained with NV35 and NV36 as a pair of primers were subjected to gel electrophoresis, a strong extra band was detected compared with those obtained with other primer pairs. Since this extra band may represent heterodimeric or homodimeric hybrids, or intramolecular hybrids derived from these primers, this template-independent hybridization could lower the efficiency of primer-dependent polymerase reaction. Of 18 primer pairs, a pair of NV81 and SRs provided the best detection of PCR products following reverse transcription of NLV RNA with SR33 or NV81. The detection rate was 61% for both reverse transcription with SR33 and that with NV81. After reverse transcription using SR33 as a primer, nested PCR using a pair of NV81 and SRs following primary PCR using a pair of NV81 and NV82/SM82 increased the detection rate to 89% in group 1 and 100% in group 2.

  4. Efficient Forest Fire Detection Index for Application in Unmanned Aerial Systems (UASs)

    PubMed Central

    Cruz, Henry; Eckert, Martina; Meneses, Juan; Martínez, José-Fernán

    2016-01-01

    This article proposes a novel method for detecting forest fires, through the use of a new color index, called the Forest Fire Detection Index (FFDI), developed by the authors. The index is based on methods for vegetation classification and has been adapted to detect the tonalities of flames and smoke; the latter could be included adaptively into the Regions of Interest (RoIs) with the help of a variable factor. Multiple tests have been performed upon database imagery and present promising results: a detection precision of 96.82% has been achieved for image sizes of 960 × 540 pixels at a processing time of 0.0447 seconds. This achievement would lead to a performance of 22 f/s, for smaller images, while up to 54 f/s could be reached by maintaining a similar detection precision. Additional tests have been performed on fires in their early stages, achieving a precision rate of p = 96.62%. The method could be used in real-time in Unmanned Aerial Systems (UASs), with the aim of monitoring a wider area than through fixed surveillance systems. Thus, it would result in more cost-effective outcomes than conventional systems implemented in helicopters or satellites. UASs could also reach inaccessible locations without jeopardizing people’s safety. On-going work includes implementation into a commercially available drone. PMID:27322264

  5. Efficient Forest Fire Detection Index for Application in Unmanned Aerial Systems (UASs).

    PubMed

    Cruz, Henry; Eckert, Martina; Meneses, Juan; Martínez, José-Fernán

    2016-06-16

    This article proposes a novel method for detecting forest fires, through the use of a new color index, called the Forest Fire Detection Index (FFDI), developed by the authors. The index is based on methods for vegetation classification and has been adapted to detect the tonalities of flames and smoke; the latter could be included adaptively into the Regions of Interest (RoIs) with the help of a variable factor. Multiple tests have been performed upon database imagery and present promising results: a detection precision of 96.82% has been achieved for image sizes of 960 × 540 pixels at a processing time of 0.0447 seconds. This achievement would lead to a performance of 22 f/s, for smaller images, while up to 54 f/s could be reached by maintaining a similar detection precision. Additional tests have been performed on fires in their early stages, achieving a precision rate of p = 96.62%. The method could be used in real-time in Unmanned Aerial Systems (UASs), with the aim of monitoring a wider area than through fixed surveillance systems. Thus, it would result in more cost-effective outcomes than conventional systems implemented in helicopters or satellites. UASs could also reach inaccessible locations without jeopardizing people's safety. On-going work includes implementation into a commercially available drone.

  6. An Efficient Distributed Coverage Hole Detection Protocol for Wireless Sensor Networks.

    PubMed

    Sahoo, Prasan Kumar; Chiang, Ming-Jer; Wu, Shih-Lin

    2016-01-01

    In wireless sensor networks (WSNs), certain areas of the monitoring region may have coverage holes and serious coverage overlapping due to the random deployment of sensors. The failure of electronic components, software bugs and destructive agents could lead to the random death of the nodes. Sensors may be dead due to exhaustion of battery power, which may cause the network to be uncovered and disconnected. Based on the deployment nature of the nodes in remote or hostile environments, such as a battlefield or desert, it is impossible to recharge or replace the battery. However, the data gathered by the sensors are highly essential for the analysis, and therefore, the collaborative detection of coverage holes has strategic importance in WSNs. In this paper, distributed coverage hole detection algorithms are designed, where nodes can collaborate to detect the coverage holes autonomously. The performance evaluation of our protocols suggests that our protocols outperform in terms of hole detection time, limited power consumption and control packet overhead to detect holes as compared to other similar protocols. PMID:26999143

  7. Handheld Lasers Allow Efficient Detection of Fluorescent Marked Organisms in the Field

    PubMed Central

    Fleischer, Shelby J.; De Moraes, Consuelo M.; Mescher, Mark C.; Tooker, John F.

    2015-01-01

    Marking organisms with fluorescent dyes and powders is a common technique used in ecological field studies that monitor movement of organisms to examine life history traits, behaviors, and population dynamics. External fluorescent marking is relatively inexpensive and can be readily employed to quickly mark large numbers of individuals; however, the ability to detect marked organisms in the field at night has been hampered by the limited detection distances provided by portable fluorescent ultraviolet lamps. In recent years, significant advances in LED lamp and laser technology have led to development of powerful, low-cost ultraviolet light sources. In this study, we evaluate the potential of these new technologies to improve detection of fluorescent-marked organisms in the field and to create new possibilities for tracking marked organisms in visually challenging environments such as tree canopies and aquatic habitats. Using handheld lasers, we document a method that provides a fivefold increase in detection distance over previously available technologies. This method allows easy scouting of tree canopies (from the ground), as well as shallow aquatic systems. This novel detection method for fluorescent-marked organisms thus promises to significantly enhance the use of fluorescent marking as a non-destructive technique for tracking organisms in natural environments, facilitating field studies that aim to document otherwise inaccessible aspects of the movement, behavior, and population dynamics of study organisms, including species with significant economic impacts or relevance for ecology and human health. PMID:26035303

  8. Improved efficiency access control equipment and explosive, weapons and drug abuse detection

    SciTech Connect

    Jenkins, A.; Milford, A.; Woollven, J.

    1985-01-01

    The second generation portal explosives detector has been designed with increased detection capability and convenience in service. The method of detection and performance relative to the first generation is described. A novel method of auto-calibration and self diagnosis is described and results are discussed. Improvements in convenience of operation have been achieved and operating space and costs reduced by combining metal detection capability, together with explosives detection. This allows both alarm signal and diagnostic outputs to be combined on a single remote panel in the guard room, and reduces the number of guards needed to man the access control. This type of access control is entirely a defensive measure against attack but a further additional feature is proposed which will also check the state of mind of all personnel passing through the check point. Any person suffering from the effect of narcotic or alcohol will be detected by their inability to reproduce their normal signature. A new method of signature analysis in five dimensions is described together with proposals for integrating the check without increasing the time in the test area. Some recent results on the effects of alcohol on signature reproduction is given.

  9. Energy-Efficient Data Reduction Techniques for Wireless Seizure Detection Systems

    PubMed Central

    Chiang, Joyce; Ward, Rabab K.

    2014-01-01

    The emergence of wireless sensor networks (WSNs) has motivated a paradigm shift in patient monitoring and disease control. Epilepsy management is one of the areas that could especially benefit from the use of WSN. By using miniaturized wireless electroencephalogram (EEG) sensors, it is possible to perform ambulatory EEG recording and real-time seizure detection outside clinical settings. One major consideration in using such a wireless EEG-based system is the stringent battery energy constraint at the sensor side. Different solutions to reduce the power consumption at this side are therefore highly desired. The conventional approach incurs a high power consumption, as it transmits the entire EEG signals wirelessly to an external data server (where seizure detection is carried out). This paper examines the use of data reduction techniques for reducing the amount of data that has to be transmitted and, thereby, reducing the required power consumption at the sensor side. Two data reduction approaches are examined: compressive sensing-based EEG compression and low-complexity feature extraction. Their performance is evaluated in terms of seizure detection effectiveness and power consumption. Experimental results show that by performing low-complexity feature extraction at the sensor side and transmitting only the features that are pertinent to seizure detection to the server, a considerable overall saving in power is achieved. The battery life of the system is increased by 14 times, while the same seizure detection rate as the conventional approach (95%) is maintained. PMID:24469356

  10. An Efficient Distributed Coverage Hole Detection Protocol for Wireless Sensor Networks

    PubMed Central

    Kumar Sahoo, Prasan; Chiang, Ming-Jer; Wu, Shih-Lin

    2016-01-01

    In wireless sensor networks (WSNs), certain areas of the monitoring region may have coverage holes and serious coverage overlapping due to the random deployment of sensors. The failure of electronic components, software bugs and destructive agents could lead to the random death of the nodes. Sensors may be dead due to exhaustion of battery power, which may cause the network to be uncovered and disconnected. Based on the deployment nature of the nodes in remote or hostile environments, such as a battlefield or desert, it is impossible to recharge or replace the battery. However, the data gathered by the sensors are highly essential for the analysis, and therefore, the collaborative detection of coverage holes has strategic importance in WSNs. In this paper, distributed coverage hole detection algorithms are designed, where nodes can collaborate to detect the coverage holes autonomously. The performance evaluation of our protocols suggests that our protocols outperform in terms of hole detection time, limited power consumption and control packet overhead to detect holes as compared to other similar protocols. PMID:26999143

  11. Handheld lasers allow efficient detection of fluorescent marked organisms in the field.

    PubMed

    Rice, Kevin B; Fleischer, Shelby J; De Moraes, Consuelo M; Mescher, Mark C; Tooker, John F; Gish, Moshe

    2015-01-01

    Marking organisms with fluorescent dyes and powders is a common technique used in ecological field studies that monitor movement of organisms to examine life history traits, behaviors, and population dynamics. External fluorescent marking is relatively inexpensive and can be readily employed to quickly mark large numbers of individuals; however, the ability to detect marked organisms in the field at night has been hampered by the limited detection distances provided by portable fluorescent ultraviolet lamps. In recent years, significant advances in LED lamp and laser technology have led to development of powerful, low-cost ultraviolet light sources. In this study, we evaluate the potential of these new technologies to improve detection of fluorescent-marked organisms in the field and to create new possibilities for tracking marked organisms in visually challenging environments such as tree canopies and aquatic habitats. Using handheld lasers, we document a method that provides a fivefold increase in detection distance over previously available technologies. This method allows easy scouting of tree canopies (from the ground), as well as shallow aquatic systems. This novel detection method for fluorescent-marked organisms thus promises to significantly enhance the use of fluorescent marking as a non-destructive technique for tracking organisms in natural environments, facilitating field studies that aim to document otherwise inaccessible aspects of the movement, behavior, and population dynamics of study organisms, including species with significant economic impacts or relevance for ecology and human health.

  12. Efficient Forest Fire Detection Index for Application in Unmanned Aerial Systems (UASs).

    PubMed

    Cruz, Henry; Eckert, Martina; Meneses, Juan; Martínez, José-Fernán

    2016-01-01

    This article proposes a novel method for detecting forest fires, through the use of a new color index, called the Forest Fire Detection Index (FFDI), developed by the authors. The index is based on methods for vegetation classification and has been adapted to detect the tonalities of flames and smoke; the latter could be included adaptively into the Regions of Interest (RoIs) with the help of a variable factor. Multiple tests have been performed upon database imagery and present promising results: a detection precision of 96.82% has been achieved for image sizes of 960 × 540 pixels at a processing time of 0.0447 seconds. This achievement would lead to a performance of 22 f/s, for smaller images, while up to 54 f/s could be reached by maintaining a similar detection precision. Additional tests have been performed on fires in their early stages, achieving a precision rate of p = 96.62%. The method could be used in real-time in Unmanned Aerial Systems (UASs), with the aim of monitoring a wider area than through fixed surveillance systems. Thus, it would result in more cost-effective outcomes than conventional systems implemented in helicopters or satellites. UASs could also reach inaccessible locations without jeopardizing people's safety. On-going work includes implementation into a commercially available drone. PMID:27322264

  13. AN EFFICIENT APPROXIMATION TO THE LIKELIHOOD FOR GRAVITATIONAL WAVE STOCHASTIC BACKGROUND DETECTION USING PULSAR TIMING DATA

    SciTech Connect

    Ellis, J. A.; Siemens, X.; Van Haasteren, R.

    2013-05-20

    Direct detection of gravitational waves by pulsar timing arrays will become feasible over the next few years. In the low frequency regime (10{sup -7} Hz-10{sup -9} Hz), we expect that a superposition of gravitational waves from many sources will manifest itself as an isotropic stochastic gravitational wave background. Currently, a number of techniques exist to detect such a signal; however, many detection methods are computationally challenging. Here we introduce an approximation to the full likelihood function for a pulsar timing array that results in computational savings proportional to the square of the number of pulsars in the array. Through a series of simulations we show that the approximate likelihood function reproduces results obtained from the full likelihood function. We further show, both analytically and through simulations, that, on average, this approximate likelihood function gives unbiased parameter estimates for astrophysically realistic stochastic background amplitudes.

  14. On the scintillation efficiency of carborane-loaded liquid scintillators for thermal neutron detection

    NASA Astrophysics Data System (ADS)

    Chang, Zheng; Okoye, Nkemakonam C.; Urffer, Matthew J.; Green, Alexander D.; Childs, Kyle E.; Miller, Laurence F.

    2015-01-01

    The scintillation efficiency in response to thermal neutrons was studied by loading different concentrations of carborane (0-8.5 wt%) and naphthalene (0 and 100 g/L) in five liquid organic scintillators. The sample was characterized in Pb and Cd shields under the irradiation of the thermal neutrons from a 252Cf source. A method was developed to extract the net neutron response from the pulse-height spectra. It was found that the order of scintillation efficiencies for both γ-rays and thermal neutrons is as follows: diisopropylnaphthalene>toluene (concentrated solutes)>toluene~pseudocumene~m-xylene. The quench constants, obtained by fitting the Stern-Volmer model to the plots of light output versus carborane concentration, are in the range of 0.35-1.4 M-1 for all the scintillators. The Birks factors, estimated using the specific energy loss profiles of the incident particles, are in the range of 9.3-14 mg cm-2 MeV-1 for all the samples. The light outputs are in the range of 63-86 keV electron equivalents (keVee) in response to thermal neutrons. Loading naphthalene generally promotes the scintillation efficiency of the scintillator with a benzene derivative solvent. Among all the scintillators tested, the diisopropylnaphthalene-based scintillator shows the highest scintillation efficiency, lowest Birks factor, and smallest quench constants. These properties are primarily attributed to the double fused benzene-ring structure of the solvent, which is more efficient to populate to the excited singlet state under ionizing radiation and to transfer the excitation energy to the fluorescent solutes.

  15. Conditions for efficient on-chip magnetic bead detection via magnetoresistive sensors.

    PubMed

    Albisetti, E; Petti, D; Cantoni, M; Damin, F; Torti, A; Chiari, M; Bertacco, R

    2013-09-15

    A commonly used figure of merit of magnetoresistive sensors employed to detect magnetic beads labeling biomolecules in lab-on-chip applications is the sensor sensitivity (S0) to external magnetic fields in the linear region of the sensor. In this paper we show that, in case of lock-in detection and bead excitation by a small AC magnetic field, S0 is not the good figure of merit to optimize. Indeed, the highest sensitivity to the magnetic beads is achieved biasing the sensor in the region of its characteristics where the product between the DC bias field and the second derivative of the resistance with respect to the magnetic field is maximum. The validity of this criterion, derived from a phenomenological model of bead detection, is proved in case of magnetic tunneling junction sensors detecting magnetic beads with 250nm diameter. This work paves the way to the development of a new generation of sensors properly designed to maximize the bead sensitivity.

  16. Convolution Comparison Pattern: An Efficient Local Image Descriptor for Fingerprint Liveness Detection

    PubMed Central

    Gottschlich, Carsten

    2016-01-01

    We present a new type of local image descriptor which yields binary patterns from small image patches. For the application to fingerprint liveness detection, we achieve rotation invariant image patches by taking the fingerprint segmentation and orientation field into account. We compute the discrete cosine transform (DCT) for these rotation invariant patches and attain binary patterns by comparing pairs of two DCT coefficients. These patterns are summarized into one or more histograms per image. Each histogram comprises the relative frequencies of pattern occurrences. Multiple histograms are concatenated and the resulting feature vector is used for image classification. We name this novel type of descriptor convolution comparison pattern (CCP). Experimental results show the usefulness of the proposed CCP descriptor for fingerprint liveness detection. CCP outperforms other local image descriptors such as LBP, LPQ and WLD on the LivDet 2013 benchmark. The CCP descriptor is a general type of local image descriptor which we expect to prove useful in areas beyond fingerprint liveness detection such as biological and medical image processing, texture recognition, face recognition and iris recognition, liveness detection for face and iris images, and machine vision for surface inspection and material classification. PMID:26844544

  17. Efficient snoring and breathing detection based on sub-band spectral statistics.

    PubMed

    Sun, Xiang; Kim, Jin Young; Won, Yonggwan; Kim, Jung-Ja; Kim, Kyung-Ah

    2015-01-01

    Snoring, a common symptom in the general population may indicate the presence of obstructive sleep apnea (OSA). In order to detect snoring events in sleep sound recordings, a novel method was proposed in this paper. The proposed method operates by analyzing the acoustic characteristics of the snoring sounds. Based on these acoustic properties, the feature vectors are obtained using the mean and standard deviation of the sub-band spectral energy. A support vector machine is then applied to perform the frame-based classification procedure. This method was demonstrated experimentally to be effective for snoring detection. The database for detection included full-night audio recordings from four individuals who acknowledged having snoring habits. The performance of the proposed method was evaluated by classifying different events (snoring, breathing and silence) from the sleep sound recordings and comparing the classification against ground truth. The proposed algorithm was able to achieve an accuracy of 99.61% for detecting snoring events, 99.16% for breathing, and 99.55% for silence. PMID:26406075

  18. Convolution Comparison Pattern: An Efficient Local Image Descriptor for Fingerprint Liveness Detection.

    PubMed

    Gottschlich, Carsten

    2016-01-01

    We present a new type of local image descriptor which yields binary patterns from small image patches. For the application to fingerprint liveness detection, we achieve rotation invariant image patches by taking the fingerprint segmentation and orientation field into account. We compute the discrete cosine transform (DCT) for these rotation invariant patches and attain binary patterns by comparing pairs of two DCT coefficients. These patterns are summarized into one or more histograms per image. Each histogram comprises the relative frequencies of pattern occurrences. Multiple histograms are concatenated and the resulting feature vector is used for image classification. We name this novel type of descriptor convolution comparison pattern (CCP). Experimental results show the usefulness of the proposed CCP descriptor for fingerprint liveness detection. CCP outperforms other local image descriptors such as LBP, LPQ and WLD on the LivDet 2013 benchmark. The CCP descriptor is a general type of local image descriptor which we expect to prove useful in areas beyond fingerprint liveness detection such as biological and medical image processing, texture recognition, face recognition and iris recognition, liveness detection for face and iris images, and machine vision for surface inspection and material classification.

  19. Neural Evidence of Statistical Learning: Efficient Detection of Visual Regularities without Awareness

    ERIC Educational Resources Information Center

    Turk-Browne, Nicholas B.; Scholl, Brian J.; Chun, Marvin M.; Johnson, Marcia K.

    2009-01-01

    Our environment contains regularities distributed in space and time that can be detected by way of statistical learning. This unsupervised learning occurs without intent or awareness, but little is known about how it relates to other types of learning, how it affects perceptual processing, and how quickly it can occur. Here we use fMRI during…

  20. Convolution Comparison Pattern: An Efficient Local Image Descriptor for Fingerprint Liveness Detection.

    PubMed

    Gottschlich, Carsten

    2016-01-01

    We present a new type of local image descriptor which yields binary patterns from small image patches. For the application to fingerprint liveness detection, we achieve rotation invariant image patches by taking the fingerprint segmentation and orientation field into account. We compute the discrete cosine transform (DCT) for these rotation invariant patches and attain binary patterns by comparing pairs of two DCT coefficients. These patterns are summarized into one or more histograms per image. Each histogram comprises the relative frequencies of pattern occurrences. Multiple histograms are concatenated and the resulting feature vector is used for image classification. We name this novel type of descriptor convolution comparison pattern (CCP). Experimental results show the usefulness of the proposed CCP descriptor for fingerprint liveness detection. CCP outperforms other local image descriptors such as LBP, LPQ and WLD on the LivDet 2013 benchmark. The CCP descriptor is a general type of local image descriptor which we expect to prove useful in areas beyond fingerprint liveness detection such as biological and medical image processing, texture recognition, face recognition and iris recognition, liveness detection for face and iris images, and machine vision for surface inspection and material classification. PMID:26844544

  1. Prey-capture efficiency between juveniles and adults, feeding habitat and abundance of Wattled Jacana foragers in northern Pantanal, Mato Grosso state, Brazil.

    PubMed

    Forti, L R; Nóbrega, P F A

    2012-05-01

    The choice of foraging strategies implies an attempt at gaining energy by predators. Supposedly, the difference in employing the "sit and wait" or "active foraging" behavior lays in hunter skills, experience and the kind of prey consumed. With the hypothesis that "active foraging" demands no learning, in this study we compared the prey capture efficiency among Wattled Jacana juveniles and adults, and also present descriptive information about feeding habitat and the abundance variation of foragers throughout the day in the northern Pantanal. Prey capture efficiency did not differ significantly among juveniles and adults, corroborating our initial hypothesis that "active foraging" is an instinctive behavior and demands no experience to be effective. However, future work is necessary to compare the energetic quality of consumed items by juveniles and adults, searching for differences explained by adults' experience. Foraging individuals were found at an average distance of 14 m ranging from 2 to 42 m) from the margin of the sampled swamps, however 64% of the foragers were found closer to the margins. The average depth of foraging sites was 17 cm, ranging from 5 to 40 cm, although no preference for specific classes of depth was found (p > 0,05). Despite the accepted general pattern of birds being more active in the early morning, the largest number of individuals foraging was observed between 11:00 and 12:00 AM, but no significant difference was found in the abundance of foraging individuals among different periods of the day. Factors, which were not analyzed, such as food availability and presence of competitors and predators need to be studied to reveal the main factors of the spatial and temporal distribution of the Wattled Jacana.

  2. Photochemical efficiency of adult and young leaves of the neotropical understory shrub Psychotria limonensis (Rubiaceae) in response to changes in the light environment.

    PubMed

    Avalos, Gerardo; Mulkey, Stephen S

    2004-12-01

    We explored the short-term adjustment in photochemical efficiency (Fv/Fm) in adult and young leaves of the understory neotropical shrub Psychotria limonensis Krause (Rubiaceae) in response to rapid changes in the light environment. Leaves were collected from 20 individual plants growing under sun and shade conditions on Gigante Peninsula, Barro Colorado Natural Monument (Republic of Panama), during the wet season of 1996. Leaves were distributed in four sequences of light treatments (AB leaves were expanded under sun and were transferred to shade, BA leaves experienced the opposite transfer, and the controls AA and BB leaves that were expanded and maintained under sun or shade conditions). Adult and young leaves did not differ in overall photochemical efficiency. Instead, differences were found among light environments, for which leaves transferred from shade to sun showed the lowest Fv/Fm ratios. There was no relationship between photochemical efficiency and leaf temperature. In P. limonensis, understory plants are susceptible of photoinhibition independently of the leaf ontogenetic stage. The approach utilized in this experiment allowed the rapid exploration of this capacity, and could be applied to poorly studied understory species.

  3. An Efficient Nonlinear Regression Approach for Genome-wide Detection of Marginal and Interacting Genetic Variations.

    PubMed

    Lee, Seunghak; Lozano, Aurélie; Kambadur, Prabhanjan; Xing, Eric P

    2016-05-01

    Genome-wide association studies have revealed individual genetic variants associated with phenotypic traits such as disease risk and gene expressions. However, detecting pairwise interaction effects of genetic variants on traits still remains a challenge due to a large number of combinations of variants (∼10(11) SNP pairs in the human genome), and relatively small sample sizes (typically <10(4)). Despite recent breakthroughs in detecting interaction effects, there are still several open problems, including: (1) how to quickly process a large number of SNP pairs, (2) how to distinguish between true signals and SNPs/SNP pairs merely correlated with true signals, (3) how to detect nonlinear associations between SNP pairs and traits given small sample sizes, and (4) how to control false positives. In this article, we present a unified framework, called SPHINX, which addresses the aforementioned challenges. We first propose a piecewise linear model for interaction detection, because it is simple enough to estimate model parameters given small sample sizes but complex enough to capture nonlinear interaction effects. Then, based on the piecewise linear model, we introduce randomized group lasso under stability selection, and a screening algorithm to address the statistical and computational challenges mentioned above. In our experiments, we first demonstrate that SPHINX achieves better power than existing methods for interaction detection under false positive control. We further applied SPHINX to late-onset Alzheimer's disease dataset, and report 16 SNPs and 17 SNP pairs associated with gene traits. We also present a highly scalable implementation of our screening algorithm, which can screen ∼118 billion candidates of associations on a 60-node cluster in <5.5 hours. PMID:27159633

  4. Progression of aortic stenosis in adult men. Detection by noninvasive methods.

    PubMed

    Nitta, M; Nakamura, T; Hultgren, H N; Bilisoly, J; Tovey, D A

    1987-07-01

    One hundred seventy-one patients with aortic stenosis (AS) who had hemodynamic studies were evaluated by a scoring system of the seven following noninvasive variables which our laboratory had developed to estimate the severity of AS: left ventricular hypertrophy (LVH) by ECG; visible aortic valve calcification by chest x-ray examination; loudness of A2; Q to peak of systolic murmur; T-time of the carotid pulse; LV ejection time; and LVH by M-mode echocardiography. The range of the severity score is 0 to 16, and a score greater than or equal to 5 has been shown correctly to identify 93 percent of patients with severe AS (valve area less than or equal to 1.0 cm2). The present study has applied this method to the detection of progression of AS. Eleven patients (mean age, 60.4 years) were studied who had hemodynamic studies performed two to nine years apart (mean, three years). Progression of stenosis occurred in all, with an increase in mean aortic valve gradient from 23 +/- 4.7 mm Hg to 46 +/- 6.5 mm Hg (p less than 0.005). Aortic valve area decreased from 1.5 +/- 0.18 cm2 to 0.88 +/- 0.10 cm2 (p less than 0.005). Noninvasive scores increased in these patients from 0.7 +/- 0.5 to 7.1 +/- 2.3 (p less than 0.005). Thirty-five patients (mean age, 62.4 years) had repeat noninvasive studies one to six years apart (mean 3 years). Twenty-two (63 percent) had an increase in the noninvasive score of greater than or equal to 3 points, and 20 (57 percent) attained a score of greater than or equal to 5, indicating probable severe AS. The mean initial severity score was 2.2 +/- 0.3, and at the end of a mean follow-up of three years, the score was 8.3 +/- 0.6 (p less than 0.005). It is concluded that in the elderly male, progression of AS over a three-year period occurs in about 60 percent of patients, and progression can be detected by simple, noninvasive methods. PMID:3595248

  5. Energy resolution and efficiency of phonon-mediated kinetic inductance detectors for light detection

    NASA Astrophysics Data System (ADS)

    Cardani, L.; Colantoni, I.; Cruciani, A.; Di Domizio, S.; Vignati, M.; Bellini, F.; Casali, N.; Castellano, M. G.; Coppolecchia, A.; Cosmelli, C.; Tomei, C.

    2015-08-01

    The development of sensitive cryogenic light detectors is of primary interest for bolometric experiments searching for rare events like dark matter interactions or neutrino-less double beta decay. Thanks to their good energy resolution and the natural multiplexed read-out, Kinetic Inductance Detectors (KIDs) are particularly suitable for this purpose. To efficiently couple KIDs-based light detectors to the large crystals used by the most advanced bolometric detectors, active surfaces of several cm2 are needed. For this reason, we are developing phonon-mediated detectors. In this paper, we present the results obtained with a prototype consisting of four 40 nm thick aluminum resonators patterned on a 2 × 2 cm2 silicon chip, and calibrated with optical pulses and X-rays. The detector features a noise resolution σE = 154 ± 7 eV and an (18 ± 2)% efficiency.

  6. Folic acid functionalized silver nanoparticles with sensitivity and selectivity colorimetric and fluorescent detection for Hg2+ and efficient catalysis

    NASA Astrophysics Data System (ADS)

    Su, Dongyue; Yang, Xin; Xia, Qingdong; Zhang, Qi; Chai, Fang; Wang, Chungang; Qu, Fengyu

    2014-09-01

    In this research, folic acid functionalized silver nanoparticles (FA-AgNPs) were selected as a colorimetric and a ‘turn on’ fluorescent sensor for detecting Hg2+. After being added into Hg2+, AgNPs can emit stable fluorescence at 440 nm when the excitation wavelength is selected at 275 nm. The absorbance and fluorescence of the FA-AgNPs could reflect the concentration of the Hg2+ ions. Thus, we developed a simple, sensitive analytical method to detect Hg2+ based on the colorimetric and fluorescence enhancement of FA-AgNPs. The sensor exhibits two linear response ranges between absorbance and fluorescence intensity with Hg2+ concentration, respectively. Meanwhile, a detection limit of 1 nM is estimated based on the linear relationship between responses with a concentration of Hg2+. The high specificity of Hg2+ with FA-AgNPs interactions provided the excellent selectivity towards detecting Hg2+ over other metal ions (Pb2+, Mg2+, Zn2+, Ni2+, Cu2+, Co2+, Ca2+, Mn2+, Fe2+, Cd2+, Ba2+, Cr6+ and Cr3+). This will provide a simple, effective and multifunctional colorimetric and fluorescent sensor for on-site and real-time Hg2+ ion detection. The proposed method can be applied to the analysis of trace Hg2+ in lake water. Additionally, the FA-AgNPs can be used as efficient catalyst for the reduction of 4-nitrophenol and potassium hexacyanoferrate (III).

  7. An Optimized Hidden Node Detection Paradigm for Improving the Coverage and Network Efficiency in Wireless Multimedia Sensor Networks.

    PubMed

    Alanazi, Adwan; Elleithy, Khaled

    2016-01-01

    Successful transmission of online multimedia streams in wireless multimedia sensor networks (WMSNs) is a big challenge due to their limited bandwidth and power resources. The existing WSN protocols are not completely appropriate for multimedia communication. The effectiveness of WMSNs varies, and it depends on the correct location of its sensor nodes in the field. Thus, maximizing the multimedia coverage is the most important issue in the delivery of multimedia contents. The nodes in WMSNs are either static or mobile. Thus, the node connections change continuously due to the mobility in wireless multimedia communication that causes an additional energy consumption, and synchronization loss between neighboring nodes. In this paper, we introduce an Optimized Hidden Node Detection (OHND) paradigm. The OHND consists of three phases: hidden node detection, message exchange, and location detection. These three phases aim to maximize the multimedia node coverage, and improve energy efficiency, hidden node detection capacity, and packet delivery ratio. OHND helps multimedia sensor nodes to compute the directional coverage. Furthermore, an OHND is used to maintain a continuous node- continuous neighbor discovery process in order to handle the mobility of the nodes. We implement our proposed algorithms by using a network simulator (NS2). The simulation results demonstrate that nodes are capable of maintaining direct coverage and detecting hidden nodes in order to maximize coverage and multimedia node mobility. To evaluate the performance of our proposed algorithms, we compared our results with other known approaches. PMID:27618048

  8. An Optimized Hidden Node Detection Paradigm for Improving the Coverage and Network Efficiency in Wireless Multimedia Sensor Networks

    PubMed Central

    Alanazi, Adwan; Elleithy, Khaled

    2016-01-01

    Successful transmission of online multimedia streams in wireless multimedia sensor networks (WMSNs) is a big challenge due to their limited bandwidth and power resources. The existing WSN protocols are not completely appropriate for multimedia communication. The effectiveness of WMSNs varies, and it depends on the correct location of its sensor nodes in the field. Thus, maximizing the multimedia coverage is the most important issue in the delivery of multimedia contents. The nodes in WMSNs are either static or mobile. Thus, the node connections change continuously due to the mobility in wireless multimedia communication that causes an additional energy consumption, and synchronization loss between neighboring nodes. In this paper, we introduce an Optimized Hidden Node Detection (OHND) paradigm. The OHND consists of three phases: hidden node detection, message exchange, and location detection. These three phases aim to maximize the multimedia node coverage, and improve energy efficiency, hidden node detection capacity, and packet delivery ratio. OHND helps multimedia sensor nodes to compute the directional coverage. Furthermore, an OHND is used to maintain a continuous node– continuous neighbor discovery process in order to handle the mobility of the nodes. We implement our proposed algorithms by using a network simulator (NS2). The simulation results demonstrate that nodes are capable of maintaining direct coverage and detecting hidden nodes in order to maximize coverage and multimedia node mobility. To evaluate the performance of our proposed algorithms, we compared our results with other known approaches. PMID:27618048

  9. Improving test interpretation for detecting executive dysfunction in adults and older adults: prevalence of low scores on the test of verbal conceptualization and fluency.

    PubMed

    Brooks, Brian L; Iverson, Grant L; Lanting, Shawnda C; Horton, Arthur M; Reynolds, Cecil R

    2012-01-01

    Knowing the prevalence of low scores on a battery of executive-functioning tests supplements clinical interpretation and can reduce the likelihood of misdiagnosing deficits in executive functioning. The purpose of this study is to examine the base rates of low scores on the Test of Verbal Conceptualization and Fluency (TVCF; Reynolds & Horton, 2006 ) in healthy adults (n = 332; M (age) = 33.0 years, SD = 10.5, range = 20-59) and older adults (n = 138; M (age) = 74.9 years, SD = 7.8, range = 60-89) from the TVCF standardization sample. The TVCF consists of four tests of executive functioning (i.e., Category Fluency, Letter Naming, Classification, and Trails C) that provide five age-adjusted T-scores. The prevalence of low scores was examined in the total sample and was stratified by educational level. When the five T-scores were considered simultaneously, having one or more scores that were 1 standard deviation (SD) below the mean was found in 28% of healthy adults and 38% of older adults. Education-based differences were also present with more lenient cutoff scores (e.g., 1 SD) but not with more conservative cutoffs. Consistent with the existing literature on other test batteries, at least one low subtest score on the TVCF is common in healthy adults and older adults.

  10. An Optimal Bahadur-Efficient Method in Detection of Sparse Signals with Applications to Pathway Analysis in Sequencing Association Studies

    PubMed Central

    Wu, Guodong; Wu, Michael; Zhi, Degui

    2016-01-01

    Next-generation sequencing data pose a severe curse of dimensionality, complicating traditional "single marker—single trait" analysis. We propose a two-stage combined p-value method for pathway analysis. The first stage is at the gene level, where we integrate effects within a gene using the Sequence Kernel Association Test (SKAT). The second stage is at the pathway level, where we perform a correlated Lancaster procedure to detect joint effects from multiple genes within a pathway. We show that the Lancaster procedure is optimal in Bahadur efficiency among all combined p-value methods. The Bahadur efficiency,limε→0N(2)/N(1)=ϕ12(θ), compares sample sizes among different statistical tests when signals become sparse in sequencing data, i.e. ε →0. The optimal Bahadur efficiency ensures that the Lancaster procedure asymptotically requires a minimal sample size to detect sparse signals (PN(i)<ε→0). The Lancaster procedure can also be applied to meta-analysis. Extensive empirical assessments of exome sequencing data show that the proposed method outperforms Gene Set Enrichment Analysis (GSEA). We applied the competitive Lancaster procedure to meta-analysis data generated by the Global Lipids Genetics Consortium to identify pathways significantly associated with high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and total cholesterol. PMID:27380176

  11. An Optimal Bahadur-Efficient Method in Detection of Sparse Signals with Applications to Pathway Analysis in Sequencing Association Studies.

    PubMed

    Dai, Hongying; Wu, Guodong; Wu, Michael; Zhi, Degui

    2016-01-01

    Next-generation sequencing data pose a severe curse of dimensionality, complicating traditional "single marker-single trait" analysis. We propose a two-stage combined p-value method for pathway analysis. The first stage is at the gene level, where we integrate effects within a gene using the Sequence Kernel Association Test (SKAT). The second stage is at the pathway level, where we perform a correlated Lancaster procedure to detect joint effects from multiple genes within a pathway. We show that the Lancaster procedure is optimal in Bahadur efficiency among all combined p-value methods. The Bahadur efficiency,[Formula: see text], compares sample sizes among different statistical tests when signals become sparse in sequencing data, i.e. ε →0. The optimal Bahadur efficiency ensures that the Lancaster procedure asymptotically requires a minimal sample size to detect sparse signals ([Formula: see text]). The Lancaster procedure can also be applied to meta-analysis. Extensive empirical assessments of exome sequencing data show that the proposed method outperforms Gene Set Enrichment Analysis (GSEA). We applied the competitive Lancaster procedure to meta-analysis data generated by the Global Lipids Genetics Consortium to identify pathways significantly associated with high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and total cholesterol.

  12. Efficient extraction of virus DNA by NucliSens Extractor allows sensitive detection of hepatitis B virus by PCR.

    PubMed

    Gobbers, E; Oosterlaken, T A; van Bussel, M J; Melsert, R; Kroes, A C; Claas, E C

    2001-12-01

    The NucliSens Extractor is an automated nucleic acid isolation system based on guanidinium thiocyanate (GuSCN)-silica extraction technology. The system has been validated for the isolation of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) RNAs from human samples in combination with nucleic acid sequence-based amplification- and reverse transcription-PCR-based methods. We evaluated the extractor for hepatitis B virus (HBV) DNA extraction from human samples using a noncommercial HBV DNA PCR. Several sample pretreatment procedures in combination with the extractor were compared with the Qiagen extraction method, and the impact of the sample volume used in the extraction on the sensitivity was investigated. Heating of the lysed sample prior to extractor isolation and the use of a large sample volume resulted in highly sensitive detection of HBV DNA. Incubation of a 1-ml sample in GuSCN at 80 degrees C (10 min) and at 37 degrees C (30 min) allowed detection of 4 and 40 HBV genome equivalents/ml, respectively, in standard dilution panels. Sample lysis in GuSCN at room temperature and proteinase K treatment prior to use of the extractor were less efficient procedures. All clinical samples that were PCR positive after Qiagen extraction and/or that were HBsAg positive were also PCR positive after extractor isolation. HBV DNA, HCV RNA, and HIV type 1 RNA were efficiently coextracted from a single sample, allowing reliable detection of viral genomes.

  13. Atom probe tomography evaporation behavior of C-axis GaN nanowires: Crystallographic, stoichiometric, and detection efficiency aspects

    SciTech Connect

    Diercks, David R. Gorman, Brian P.; Kirchhofer, Rita; Sanford, Norman; Bertness, Kris; Brubaker, Matt

    2013-11-14

    The field evaporation behavior of c-axis GaN nanowires was explored in two different laser-pulsed atom probe tomography (APT) instruments. Transmission electron microscopy imaging before and after atom probe tomography analysis was used to assist in reconstructing the data and assess the observed evaporation behavior. It was found that the ionic species exhibited preferential locations for evaporation related to the underlying crystal structure of the GaN and that the species which evaporated from these locations was dependent on the pulsed laser energy. Additionally, the overall stoichiometry measured by APT was significantly correlated with the energy of the laser pulses. At the lowest laser energies, the apparent composition was nitrogen-rich, while higher laser energies resulted in measurements of predominantly gallium compositions. The percent of ions detected (detection efficiency) for these specimens was found to be considerably below that shown for other materials, even for laser energies which produced the expected Ga:N ratio. The apparent stoichiometry variation and low detection efficiency appear to be a result of evaporation of Ga ions between laser pulses at the lowest laser energies and evaporation of neutral N{sub 2} species at higher laser energies. All of these behaviors are tied to the formation of nitrogen-nitrogen bonds on the tip surface, which occurred under all analysis conditions. Similar field evaporation behaviors are therefore expected for other materials where the anionic species readily form a strong diatomic bond.

  14. Monte Carlo simulation of the movement and detection efficiency of a whole-body counting system using a BOMAB phantom.

    PubMed

    Bento, Joana; Barros, Sílvia; Teles, Pedro; Neves, Maria; Gonçalves, Isabel; Corisco, José; Vaz, Pedro

    2012-03-01

    This study reports on the computational analysis and experimental calibration of the whole-body counting detection equipment at the Nuclear and Technological Institute (ITN) in Portugal. Two state-of-the-art Monte Carlo simulation programmes were used for this purpose: PENELOPE and MCNPX. This computational work was undertaken as part of a new set of experimental calibrations, which improved the quality standards of this study's WBC system. In these calibrations, a BOMAB phantom, one of the industry standards phantoms for WBC calibrations in internal dosimetry applications, was used. Both the BOMAB phantom and the detection system were accurately implemented in the Monte Carlo codes. The whole-body counter at ITN possesses a moving detector system, which poses a challenge for Monte Carlo simulations, as most codes only accept static configurations. The continuous detector movement was approximately described in the simulations by averaging several discrete positions of the detector throughout the movement. The computational efficiency values obtained with the two Monte Carlos codes have deviations of less than 3.2 %, and the obtained deviations between experimental and computational efficiencies are less than 5 %. This work contributes to demonstrate the great effectiveness of using computational tools for understanding the calibration of radiation detection systems used for in vivo monitoring.

  15. Change Detection in Naturalistic Pictures among Children with Autism

    ERIC Educational Resources Information Center

    Burack, Jacob A.; Joseph, Shari; Russo, Natalie; Shore, David I.; Porporino, Mafalda; Enns, James T.

    2009-01-01

    Persons with autism often show strong reactions to changes in the environment, suggesting that they may detect changes more efficiently than typically developing (TD) persons. However, Fletcher-Watson et al. (Br J Psychol 97:537-554, 2006) reported no differences between adults with autism and TD adults with a change-detection task. In this study,…

  16. Exploiting Habitat and Gear Patterns for Efficient Detection of Rare and Non-native Benthos and Fish in Great Lakes Coastal ecosystems

    EPA Science Inventory

    There is at present no comprehensive early-detection monitoring for exotic species in the Great Lakes, despite their continued arrival and impacts and recognition that early detection is key to effective management. We evaluated strategies for efficient early-detection monitorin...

  17. Layout and language: an efficient algorithm for detecting text blocks based on spatial and linguistic evidence

    NASA Astrophysics Data System (ADS)

    Hurst, Matthew

    2000-12-01

    The ability to accurately detect those areas in plain text documents that consist of contiguous text is an important pre- process to many applications. This paper introduces a novel method that uses both spatial and linguistic knowledge in an accurate manner to provide an initial analysis of the document. This initial analysis may then be extended to provide a complete analysis of the text areas in the document.

  18. An efficient method to detect periodic behavior in botnet traffic by analyzing control plane traffic

    PubMed Central

    AsSadhan, Basil; Moura, José M.F.

    2013-01-01

    Botnets are large networks of bots (compromised machines) that are under the control of a small number of bot masters. They pose a significant threat to Internet’s communications and applications. A botnet relies on command and control (C2) communications channels traffic between its members for its attack execution. C2 traffic occurs prior to any attack; hence, the detection of botnet’s C2 traffic enables the detection of members of the botnet before any real harm happens. We analyze C2 traffic and find that it exhibits a periodic behavior. This is due to the pre-programmed behavior of bots that check for updates to download them every T seconds. We exploit this periodic behavior to detect C2 traffic. The detection involves evaluating the periodogram of the monitored traffic. Then applying Walker’s large sample test to the periodogram’s maximum ordinate in order to determine if it is due to a periodic component or not. If the periodogram of the monitored traffic contains a periodic component, then it is highly likely that it is due to a bot’s C2 traffic. The test looks only at aggregate control plane traffic behavior, which makes it more scalable than techniques that involve deep packet inspection (DPI) or tracking the communication flows of different hosts. We apply the test to two types of botnet, tinyP2P and IRC that are generated by SLINGbot. We verify the periodic behavior of their C2 traffic and compare it to the results we get on real traffic that is obtained from a secured enterprise network. We further study the characteristics of the test in the presence of injected HTTP background traffic and the effect of the duty cycle on the periodic behavior. PMID:25685512

  19. Efficient ECG signal analysis using wavelet technique for arrhythmia detection: an ANFIS approach

    NASA Astrophysics Data System (ADS)

    Khandait, P. D.; Bawane, N. G.; Limaye, S. S.

    2010-02-01

    This paper deals with improved ECG signal analysis using Wavelet Transform Techniques and employing subsequent modified feature extraction for Arrhythmia detection based on Neuro-Fuzzy technique. This improvement is based on suitable choice of features in evaluating and predicting life threatening Ventricular Arrhythmia . Analyzing electrocardiographic signals (ECG) includes not only inspection of P, QRS and T waves, but also the causal relations they have and the temporal sequences they build within long observation periods. Wavelet-transform is used for effective feature extraction and Adaptive Neuro-Fuzzy Inference System (ANFIS) is considered for the classifier model. In a first step, QRS complexes are detected. Then, each QRS is delineated by detecting and identifying the peaks of the individual waves, as well as the complex onset and end. Finally, the determination of P and T wave peaks, onsets and ends is performed. We evaluated the algorithm on several manually annotated databases, such as MIT-BIH Arrhythmia and CSE databases, developed for validation purposes. Features based on the ECG waveform shape and heart beat intervals are used as inputs to the classifiers. The performance of the ANFIS model is evaluated in terms of training performance and classification accuracies and the results confirmed that the proposed ANFIS model has potential in classifying the ECG signals. Cross validation is used to measure the classifier performance. A testing classification accuracy of 95.13% is achieved which is a significant improvement.

  20. MAIT Cells Detect and Efficiently Lyse Bacterially-Infected Epithelial Cells

    PubMed Central

    Bohineust, Armelle; Bessoles, Stéphanie; Martin, Emmanuel; Premel, Virginie; Coré, Maxime; Sleurs, David; Serriari, Nacer-Eddine; Treiner, Emmanuel; Hivroz, Claire; Sansonetti, Philippe; Gougeon, Marie-Lise; Soudais, Claire; Lantz, Olivier

    2013-01-01

    Mucosal associated invariant T cells (MAIT) are innate T lymphocytes that detect a large variety of bacteria and yeasts. This recognition depends on the detection of microbial compounds presented by the evolutionarily conserved major-histocompatibility-complex (MHC) class I molecule, MR1. Here we show that MAIT cells display cytotoxic activity towards MR1 overexpressing non-hematopoietic cells cocultured with bacteria. The NK receptor, CD161, highly expressed by MAIT cells, modulated the cytokine but not the cytotoxic response triggered by bacteria infected cells. MAIT cells are also activated by and kill epithelial cells expressing endogenous levels of MRI after infection with the invasive bacteria Shigella flexneri. In contrast, MAIT cells were not activated by epithelial cells infected by Salmonella enterica Typhimurium. Finally, MAIT cells are activated in human volunteers receiving an attenuated strain of Shigella dysenteriae-1 tested as a potential vaccine. Thus, in humans, MAIT cells are the most abundant T cell subset able to detect and kill bacteria infected cells. PMID:24130485

  1. In-Hospital Pneumococcal Polysaccharide Vaccination Is Associated With Detection of Pneumococcal Vaccine Serotypes in Adults Hospitalized for Community-Acquired Pneumonia.

    PubMed

    Grijalva, Carlos G; Wunderink, Richard G; Zhu, Yuwei; Williams, Derek J; Balk, Robert; Fakhran, Sherene; Courtney, D Mark; Anderson, Evan J; Qi, Chao; Trabue, Christopher; Pavia, Andrew T; Moore, Matthew R; Jain, Seema; Edwards, Kathryn M; Self, Wesley H

    2015-12-01

    During an etiology study of adults hospitalized for pneumonia, in which urine specimens were examined for serotype-specific pneumococcal antigen detection, we observed that some patients received 23-valent pneumococcal polysaccharide vaccine before urine collection. Some urine samples became positive for specific vaccine pneumococcal serotypes shortly after vaccination, suggesting false-positive test results. PMID:26512357

  2. Gap Detection in School-Age Children and Adults: Effects of Inherent Envelope Modulation and the Availability of Cues across Frequency

    ERIC Educational Resources Information Center

    Buss, Emily; Hall, Joseph W., III; Porter, Heather; Grose, John H.

    2014-01-01

    Purpose: The present study evaluated the effects of inherent envelope modulation and the availability of cues across frequency on behavioral gap detection with noise-band stimuli in school-age children. Method: Listeners were 34 normal-hearing children (ages 5.2-15.6 years) and 12 normal-hearing adults (ages 18.5-28.8 years). Stimuli were…

  3. Face Detection in Complex Visual Displays: An Eye-Tracking Study with 3- and 6-Month-Old Infants and Adults

    ERIC Educational Resources Information Center

    Di Giorgio, Elisa; Turati, Chiara; Altoe, Gianmarco; Simion, Francesca

    2012-01-01

    The ability to detect and prefer a face when embedded in complex visual displays was investigated in 3- and 6-month-old infants, as well as in adults, through a modified version of the visual search paradigm and the recording of eye movements. Participants "(N" = 43) were shown 32 visual displays that comprised a target face among 3 or 5…

  4. Unmetabolized Folic Acid Is Detected in Nearly All Serum Samples from US Children, Adolescents, and Adults1234

    PubMed Central

    Pfeiffer, Christine M; Sternberg, Maya R; Fazili, Zia; Yetley, Elizabeth A; Lacher, David A; Bailey, Regan L; Johnson, Clifford L

    2015-01-01

    Background: Serum total folate consists mainly of 5-methyltetrahydrofolate (5-methylTHF). Unmetabolized folic acid (UMFA) may occur in persons consuming folic acid–fortified foods or supplements. Objectives: We describe serum 5-methylTHF and UMFA concentrations in the US population ≥1 y of age by demographic variables and fasting time, stratified by folic acid–containing dietary supplement use. We also evaluate factors associated with UMFA concentrations >1 nmol/L. Methods: Serum samples from the cross-sectional NHANES 2007–2008 were measured for 5-methylTHF (n = 2734) and UMFA (n = 2707) by HPLC–tandem mass spectrometry. Results: In supplement users compared with nonusers, we found significantly higher geometric mean concentrations of 5-methylTHF (48.4 and 30.7 nmol/L, respectively) and UMFA (1.54 and 0.794 nmol/L, respectively). UMFA concentrations were detectable (>0.3 nmol/L) in >95% of supplement users and nonusers, regardless of demographic or fasting characteristics; concentrations differed significantly by age and fasting time, but not by sex and race-ethnicity, both in supplement users and nonusers. The prevalence of UMFA concentrations >1 nmol/L was 33.2% overall and 21.0% in fasting (≥8 h) adults (≥20 y of age). Using multiple logistic regression analysis, UMFA concentrations >1 nmol/L were associated with being older, non-Hispanic black, nonfasting (<8 h), having smaller body surface area, higher total folic acid intake (diet and supplements), and higher red blood cell folate concentrations. In fasting adults, a decrease in the mean daily alcohol consumption was also associated with increased odds of UMFA concentrations >1 nmol/L. Conclusions: UMFA detection was nearly ubiquitous, and concentrations >1 nmol/L were largely but not entirely explained by fasting status and by total folic acid intake from diet and supplements. These new UMFA data in US persons ≥1 y of age provide much-needed information on this vitamer in a fortified

  5. An APD for the efficient detection of the fast scintillation component of BaF2

    NASA Astrophysics Data System (ADS)

    Hitlin, D. G.; Kim, J. H.; Trevor, J.; Hoenk, M.; Hennessy, J.; Jewell, A.; Farrell, R.; McClish, M.

    2016-07-01

    Barium fluoride crystals are the baseline choice for the calorimeter of the Mu2e experiment at Fermilab. By the fast (decay time 0.9 ns) 220 nm scintillation component and discriminating against the larger slow (decay time 630 ns) 300 nm component, it is possible to build a radiation-hard calorimeter with good energy and time resolution and high rate capability. This requires a solid state photosensor with high quantum efficiency at 220 nm, discrimination against the 300 nm component and good rise and decay times. Progress on the development of such a sensor is presented.

  6. Development of an efficient real-time quantitative PCR protocol for detection of Xanthomonas arboricola pv. pruni in Prunus species.

    PubMed

    Palacio-Bielsa, Ana; Cubero, Jaime; Cambra, Miguel A; Collados, Raquel; Berruete, Isabel M; López, María M

    2011-01-01

    Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot disease of stone fruit, is considered a quarantine organism by the European Union and the European and Mediterranean Plant Protection Organization (EPPO). The bacterium can undergo an epiphytic phase and/or be latent and can be transmitted by plant material, but currently, only visual inspections are used to certify plants as being X. arboricola pv. pruni free. A novel and highly sensitive real-time TaqMan PCR detection protocol was designed based on a sequence of a gene for a putative protein related to an ABC transporter ATP-binding system in X. arboricola pv. pruni. Pathogen detection can be completed within a few hours with a sensitivity of 10(2) CFU ml(-1), thus surpassing the sensitivity of the existing conventional PCR. Specificity was assessed for X. arboricola pv. pruni strains from different origins as well as for closely related Xanthomonas species, non-Xanthomonas species, saprophytic bacteria, and healthy Prunus samples. The efficiency of the developed protocol was evaluated with field samples of 14 Prunus species and rootstocks. For symptomatic leaf samples, the protocol was very efficient even when washed tissues of the leaves were directly amplified without any previous DNA extraction. For samples of 117 asymptomatic leaves and 285 buds, the protocol was more efficient after a simple DNA extraction, and X. arboricola pv. pruni was detected in 9.4% and 9.1% of the 402 samples analyzed, respectively, demonstrating its frequent epiphytic or endophytic phase. This newly developed real-time PCR protocol can be used as a quantitative assay, offers a reliable and sensitive test for X. arboricola pv. pruni, and is suitable as a screening test for symptomatic as well as asymptomatic plant material.

  7. Energy resolution and efficiency of phonon-mediated kinetic inductance detectors for light detection

    SciTech Connect

    Cardani, L.; Colantoni, I.; Coppolecchia, A.; Cruciani, A.; Vignati, M.; Bellini, F.; Casali, N.; Cosmelli, C.; Di Domizio, S.; Castellano, M. G.; Tomei, C.

    2015-08-31

    The development of sensitive cryogenic light detectors is of primary interest for bolometric experiments searching for rare events like dark matter interactions or neutrino-less double beta decay. Thanks to their good energy resolution and the natural multiplexed read-out, Kinetic Inductance Detectors (KIDs) are particularly suitable for this purpose. To efficiently couple KIDs-based light detectors to the large crystals used by the most advanced bolometric detectors, active surfaces of several cm{sup 2} are needed. For this reason, we are developing phonon-mediated detectors. In this paper, we present the results obtained with a prototype consisting of four 40 nm thick aluminum resonators patterned on a 2 × 2 cm{sup 2} silicon chip, and calibrated with optical pulses and X-rays. The detector features a noise resolution σ{sub E} = 154 ± 7 eV and an (18 ± 2)% efficiency.

  8. Efficient induction of Wheat-agropyron cristatum 6P translocation lines and GISH detection.

    PubMed

    Song, Liqiang; Jiang, Lili; Han, Haiming; Gao, Ainong; Yang, Xinming; Li, Lihui; Liu, Weihua

    2013-01-01

    The narrow genetic background restricts wheat yield and quality improvement. The wild relatives of wheat are the huge gene pools for wheat improvement and can broaden its genetic basis. Production of wheat-alien translocation lines can transfer alien genes to wheat. So it is important to develop an efficient method to induce wheat-alien chromosome translocation. Agropyroncristatum (P genome) carries many potential genes beneficial to disease resistance, stress tolerance and high yield. Chromosome 6P possesses the desirable genes exhibiting good agronomic traits, such as high grain number per spike, powdery mildew resistance and stress tolerance. In this study, the wheat-A. cristatum disomic addition was used as bridge material to produce wheat-A. cristatum translocation lines induced by (60)Co-γirradiation. The results of genomic in situ hybridization showed that 216 plants contained alien chromosome translocation among 571 self-pollinated progenies. The frequency of translocation was 37.83%, much higher than previous reports. Moreover, various alien translocation types were identified. The analysis of M2 showed that 62.5% of intergeneric translocation lines grew normally without losing the translocated chromosomes. The paper reported a high efficient technical method for inducing alien translocation between wheat and Agropyroncristatum. Additionally, these translocation lines will be valuable for not only basic research on genetic balance, interaction and expression of different chromosome segments of wheat and alien species, but also wheat breeding programs to utilize superior agronomic traits and good compensation effect from alien chromosomes. PMID:23874966

  9. Detecting attention-deficit/hyperactivity disorder (ADHD) in adults with intellectual disability The use of Conners' Adult ADHD Rating Scales (CAARS).

    PubMed

    La Malfa, G; Lassi, S; Bertelli, M; Pallanti, S; Albertini, G

    2008-01-01

    There is an increasing interest in the diagnosis of attention-deficit/hyperactivity disorder (ADHD) in adulthood. It is also thought that ADHD is more prevalent in the field of intellectual disability (ID) than in the general population, but there are not many experimental studies. Since ADHD diagnosis in adults is more difficult, specific rating scales correlated to the main diagnostic systems have been created but have not been applied to people with ID. This work presents an application of an ADHD screening rating scale, the Conners' Adult ADHD Rating Scales (CAARS) screening version to 46 adults with ID. The resulting prevalence of "ADHD-positive" was 19.6%. These data are in accord with results reported in the general adult literature. Our data suggest that ID and attention disorders can co-occur. Therefore, not only can ADHD be a valid psychiatric diagnosis for a child with ID but for an adult with ID as well. The CAARS can be considered a useful clinical instrument to survey ADHD in ID. PMID:17416484

  10. Numerical study of plasmonic efficiency of gold nanostripes for molecule detection.

    PubMed

    Grosges, Thomas; Barchiesi, Dominique

    2015-01-01

    In plasmonics, the accurate computation of the electromagnetic field enhancement is necessary in determining the amplitude and the spatial extension of the field around nanostructures. Here, the problem of the interaction between an electromagnetic excitation and gold nanostripes is solved. An optimization scheme, including an adaptive remeshing process with error estimator, is used to solve the problem through a finite element method. The variations of the electromagnetic field amplitude and the plasmonic active zones around nanostructures for molecule detection are studied in this paper taking into account the physical and geometrical parameters of the nanostripes. The evolution between the sizes and number of nanostripes is shown.

  11. Numerical Study of Plasmonic Efficiency of Gold Nanostripes for Molecule Detection

    PubMed Central

    2015-01-01

    In plasmonics, the accurate computation of the electromagnetic field enhancement is necessary in determining the amplitude and the spatial extension of the field around nanostructures. Here, the problem of the interaction between an electromagnetic excitation and gold nanostripes is solved. An optimization scheme, including an adaptive remeshing process with error estimator, is used to solve the problem through a finite element method. The variations of the electromagnetic field amplitude and the plasmonic active zones around nanostructures for molecule detection are studied in this paper taking into account the physical and geometrical parameters of the nanostripes. The evolution between the sizes and number of nanostripes is shown. PMID:25734184

  12. A rapid and efficient newly established method to detect COL1A1-PDGFB gene fusion in dermatofibrosarcoma protuberans

    SciTech Connect

    Yokoyama, Yoko; Shimizu, Akira; Okada, Etsuko; Ishikawa, Osamu; Motegi, Sei-ichiro

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer We developed new method to rapidly identify COL1A1-PDGFB fusion in DFSP. Black-Right-Pointing-Pointer New PCR method using a single primer pair detected COL1A1-PDGFB fusion in DFSP. Black-Right-Pointing-Pointer This is the first report of DFSP with a novel COL1A1 breakpoint in exon 5. -- Abstract: The detection of fusion transcripts of the collagen type 1{alpha}1 (COL1A1) and platelet-derived growth factor-BB (PDGFB) genes by genetic analysis has recognized as a reliable and valuable molecular tool for the diagnosis of dermatofibrosarcoma protuberans (DFSP). To detect the COL1A1-PDGFB fusion, almost previous reports performed reverse transcription polymerase chain reaction (RT-PCR) using multiplex forward primers from COL1A1. However, it has possible technical difficulties with respect to the handling of multiple primers and reagents in the procedure. The objective of this study is to establish a rapid, easy, and efficient one-step method of PCR using only a single primer pair to detect the fusion transcripts of the COL1A1 and PDGFB in DFSP. To validate new method, we compared the results of RT-PCR in five patients of DFSP between the previous method using multiplex primers and our established one-step RT-PCR using a single primer pair. In all cases of DFSP, the COL1A1-PDGFB fusion was detected by both previous method and newly established one-step PCR. Importantly, we detected a novel COL1A1 breakpoint in exon 5. The newly developed method is valuable to rapidly identify COL1A1-PDGFB fusion transcripts in DFSP.

  13. How Often Should We Monitor for Reliable Detection of Atrial Fibrillation Recurrence? Efficiency Considerations and Implications for Study Design

    PubMed Central

    Charitos, Efstratios I.; Ziegler, Paul D.; Stierle, Ulrich; Robinson, Derek R.; Graf, Bernhard; Sievers, Hans-Hinrich; Hanke, Thorsten

    2014-01-01

    Objective Although atrial fibrillation (AF) recurrence is unpredictable in terms of onset and duration, current intermittent rhythm monitoring (IRM) diagnostic modalities are short-termed and discontinuous. The aim of the present study was to investigate the necessary IRM frequency required to reliably detect recurrence of various AF recurrence patterns. Methods The rhythm histories of 647 patients (mean AF burden: 12±22% of monitored time; 687 patient-years) with implantable continuous monitoring devices were reconstructed and analyzed. With the use of computationally intensive simulation, we evaluated the necessary IRM frequency to reliably detect AF recurrence of various AF phenotypes using IRM of various durations. Results The IRM frequency required for reliable AF detection depends on the amount and temporal aggregation of the AF recurrence (p<0.0001) as well as the duration of the IRM (p<0.001). Reliable detection (>95% sensitivity) of AF recurrence required higher IRM frequencies (>12 24-hour; >6 7-day; >4 14-day; >3 30-day IRM per year; p<0.0001) than currently recommended. Lower IRM frequencies will under-detect AF recurrence and introduce significant bias in the evaluation of therapeutic interventions. More frequent but of shorter duration, IRMs (24-hour) are significantly more time effective (sensitivity per monitored time) than a fewer number of longer IRM durations (p<0.0001). Conclusions Reliable AF recurrence detection requires higher IRM frequencies than currently recommended. Current IRM frequency recommendations will fail to diagnose a significant proportion of patients. Shorter duration but more frequent IRM strategies are significantly more efficient than longer IRM durations. Clinical Trial Registration URL Unique identifier: NCT00806689. PMID:24563690

  14. A simple and efficient design to improve the detection of biotin-streptavidin interaction with plasmonic nanobiosensors.

    PubMed

    Focsan, Monica; Campu, Andreea; Craciun, Ana-Maria; Potara, Monica; Leordean, Cosmin; Maniu, Dana; Astilean, Simion

    2016-12-15

    In this manuscript we propose a simple and efficient strategy to improve the sensitivity of localized surface plasmon resonance (LSPR) shift-based biosensors using biotin-streptavidin recognition interaction as a proof-of-concept. Specifically, biotin molecules are immobilized on a low-cost plasmonic LSPR biosensor based on annealed self-assembled spherical gold nanoparticles (AuNSs) and successively incubated with increasing concentrations of streptavidin, achieving a limit of detection (LOD) of 5nM. Interestingly, when the detection is performed by the same biotin-functionalized plasmonic AuNSs substrate but against streptavidin previously conjugated to gold nanorods, the LSPR shift is 26-fold enhanced. Moreover, we confirm these results through numerical simulations and demonstrate that the proposed sensing architecture can operate as transducer not only to confirm the adsorption of bioanalyte but also to provide the chemical identity of the capture and targeted molecules from their vibrational Raman fingerprints. Therefore, we are confident that the development of such plasmonic biosensors that use metallic labels for improving the sensitivity of detection could become highly promising for future point-of-care diagnostic assays, pushing sensitivity towards single-molecule detection limit.

  15. Efficient Two-Photon Fluorescent Probe for Nitroreductase Detection and Hypoxia Imaging in Tumor Cells and Tissues.

    PubMed

    Zhang, Jing; Liu, Hong-Wen; Hu, Xiao-Xiao; Li, Jin; Liang, Li-Hui; Zhang, Xiao-Bing; Tan, Weihong

    2015-12-01

    Hypoxia plays an important role in tumor progression, and the development of efficient methods for monitoring hypoxic degree in living systems is of great biomedical importance. In the solid tumors, the nitroreductase level is directly corresponded with the hypoxic status. Many one-photon excited fluorescent probes have been developed for hypoxia imaging in tumor cells via the detection of nitroreductase level. However, two-photon excited probes are more suitable for bioimaging. In this work, a two-photon probe 1 for nitroreductase detection and hypoxic status monitoring in living tumor cells and tissues was reported for the first time. The detection is based on the fact that the nitro-group of probe 1 could be selectively reduced to an amino-group by nitroreductase in the presence of reduced NADH, following by a 1,6-rearrangement-elimination to release the fluorophore, resulting in the enhancement of fluorescence. The probe exhibited both one-photon and two-photon excited remarkable fluorescence enhancement (∼70-fold) for nitroreductase, which afforded a high sensitivity for nitroreductase, with a detection limit of 20 ng/mL observed. Moreover, the applications of the probe for fluorescent bioimaging of hypoxia in living cells and two-photon bioimaging in tissues were carried out, with tissue-imaging depths of 70-160 μm observed, which demonstrates its practical application in complex biosystems.

  16. Efficient live face detection to counter spoof attack in face recognition systems

    NASA Astrophysics Data System (ADS)

    Biswas, Bikram Kumar; Alam, Mohammad S.

    2015-03-01

    Face recognition is a critical tool used in almost all major biometrics based security systems. But recognition, authentication and liveness detection of the face of an actual user is a major challenge because an imposter or a non-live face of the actual user can be used to spoof the security system. In this research, a robust technique is proposed which detects liveness of faces in order to counter spoof attacks. The proposed technique uses a three-dimensional (3D) fast Fourier transform to compare spectral energies of a live face and a fake face in a mathematically selective manner. The mathematical model involves evaluation of energies of selective high frequency bands of average power spectra of both live and non-live faces. It also carries out proper recognition and authentication of the face of the actual user using the fringe-adjusted joint transform correlation technique, which has been found to yield the highest correlation output for a match. Experimental tests show that the proposed technique yields excellent results for identifying live faces.

  17. Efficient detection and signal parameter estimation with application to high dynamic GPS receiver

    NASA Technical Reports Server (NTRS)

    Kumar, Rajendra (Inventor)

    1990-01-01

    In a system for deriving position, velocity, and acceleration information from a received signal emitted from an object to be tracked wherein the signal comprises a carrier signal phase modulated by unknown binary data and experiencing very high Doppler and Doppler rate, this invention provides combined estimation/detection apparatus for simultaneously detecting data bits and obtaining estimates of signal parameters such as carrier phase and frequency related to receiver dynamics in a sequential manner. There is a first stage for obtaining estimates of the signal parameters related to phase and frequency in the vicinity of possible data transitions on the basis of measurements obtained within a current data bit. A second stage uses the estimates from the first stage to decide whether or not a data transition has actually occurred. There is a third stage for removing data modulation from the received signal when a data transition has occurred and a fourth stage for using the received signal with data modulation removed therefrom to update global parameters which are dependent only upon receiver dynamics and independent of data modulation. Finally, there is a fifth stage for using the global parameters to determine the position, velocity, and acceleration of the object.

  18. An efficient promoter trap for detection of patterned gene expression and subsequent functional analysis in Drosophila.

    PubMed

    Larsen, Camilla; Franch-Marro, Xavier; Hartenstein, Volker; Alexandre, Cyrille; Vincent, Jean-Paul

    2006-11-21

    Transposable elements have been used in Drosophila to detect gene expression, inactivate gene function, and induce ectopic expression or overexpression. We have combined all of these features in a single construct. A promoterless GAL4 cDNA is expressed when the construct inserts within a transcriptional unit, and GAL4 activates a GFP-encoding gene present in the same transposon. In a primary screen, patterned gene expression is detected as GFP fluorescence in the live progeny of dysgenic males. Many animals expressing GFP in distinct patterns can be recovered with relatively little effort. As expected, many insertions cause loss of function. After insertion at a genomic location, specific parts of the transposon can be excised by FLP recombinase, thus allowing it to induce conditional misexpression of the tagged gene. Therefore, both gain- and loss-of-function studies can be carried out with a single insertion in a gene identified by virtue of its expression pattern. Using this promoter trap approach, we have identified a group of cells that innervate the calyx of the mushroom body and could thus define a previously unrecognized memory circuit. PMID:17093046

  19. An efficient screening method for simultaneous detection of recurrent copy number variants associated with psychiatric disorders.

    PubMed

    Rodriguez-Lopez, Julio; Carrera, Noa; Arrojo, Manuel; Amigo, Jorge; Sobrino, Beatriz; Páramo, Mario; Paz, Eduardo; Agra, Santiago; Ramos-Ríos, Ramón; Brenlla, Julio; Carracedo, Ángel; Costas, Javier

    2015-05-20

    Several recurrent copy number variants (CNVs) increasing risk to neuropsychiatric diseases have been identified in recent years. They show variable clinical expressivity, being associated with different disorders, and incomplete penetrance. However, due to its very low frequency, the full variety of clinical outcomes associated with each one of these CNVs is unknown. Current methods for detection of CNVs are labor intensive, expensive or not suitable for high throughput analysis. Quantitative interspecies competitive PCR linked to variant minisequencing and detection by mass-spectrometry may overcome these limitations. Here, we present two multiplex assays based on this method to screen for eleven psychiatric risk CNVs, such as 1q21, 16p11.2, 3q29, or 16p13.11 regions, among others. The assays were tested in our collection of 514 schizophrenia patients. Results were compared with MLPA at two CNVs. Additional positive results were confirmed by exome sequencing. A total of fourteen patients were CNV carriers. The method presents high sensitivity and specificity, showing its utility as a cheap, accurate, high throughput screening tool for recurrent CNVs. The method may be very useful for management of psychiatric patients as well as screening of different collections of samples to better identify the full spectrum of clinical variability. PMID:25797897

  20. A dimension reduction strategy for improving the efficiency of computer-aided detection for CT colonography

    NASA Astrophysics Data System (ADS)

    Song, Bowen; Zhang, Guopeng; Wang, Huafeng; Zhu, Wei; Liang, Zhengrong

    2013-02-01

    Various types of features, e.g., geometric features, texture features, projection features etc., have been introduced for polyp detection and differentiation tasks via computer aided detection and diagnosis (CAD) for computed tomography colonography (CTC). Although these features together cover more information of the data, some of them are statistically highly-related to others, which made the feature set redundant and burdened the computation task of CAD. In this paper, we proposed a new dimension reduction method which combines hierarchical clustering and principal component analysis (PCA) for false positives (FPs) reduction task. First, we group all the features based on their similarity using hierarchical clustering, and then PCA is employed within each group. Different numbers of principal components are selected from each group to form the final feature set. Support vector machine is used to perform the classification. The results show that when three principal components were chosen from each group we can achieve an area under the curve of receiver operating characteristics of 0.905, which is as high as the original dataset. Meanwhile, the computation time is reduced by 70% and the feature set size is reduce by 77%. It can be concluded that the proposed method captures the most important information of the feature set and the classification accuracy is not affected after the dimension reduction. The result is promising and further investigation, such as automatically threshold setting, are worthwhile and are under progress.

  1. Design of a polarization-insensitive superconducting nanowire single photon detector with high detection efficiency

    NASA Astrophysics Data System (ADS)

    Zheng, Fan; Xu, Ruiying; Zhu, Guanghao; Jin, Biaobing; Kang, Lin; Xu, Weiwei; Chen, Jian; Wu, Peiheng

    2016-03-01

    Superconducting nanowire single photon detectors (SNSPDs) deliver superior performance over their competitors in the near-infrared regime. However, these detectors have an intrinsic polarization dependence on the incident wave because of their one-dimensional meander structure. In this paper, we propose an approach to eliminate the polarization sensitivity of SNSPDs by using near-field optics to increase the absorption of SNSPDs under transverse magnetic (TM) illumination. In addition, an optical cavity is added to our SNSPD to obtain nearly perfect absorption of the incident wave. Numerical simulations show that the maximum absorption of a designed SNSPD can reach 96% at 1550 nm, and indicate that the absorption difference between transverse electric (TE) and TM polarization is less than 0.5% across a wavelength window of 300 nm. Our work provides the first demonstration of the possibility of designing a polarization-insensitive and highly efficient SNSPD without performing device symmetry improvements.

  2. CsTb2F7: an efficient radioluminescent material for fiberoptic radiation detection

    NASA Astrophysics Data System (ADS)

    Molina, P.; Marcazzó, J.; Caselli, E.; Khaidukov, N. M.; Santiago, M.

    2011-01-01

    In this article, the feasibility of using CsTb2F7 crystals as scintillating detectors to build radioluminescent fiberoptic dosimetry (FOD) probes has been investigated for the first time. The radioluminescence (RL) efficiency of this compound has been found to be more than twice as high as that of commercial Al2O3:C detectors under excitation with gamma radiation from a 60Co source. Additionally, the intensity of the RL signal shows no dependence on the accumulated dose. Both RL and photoluminescence spectra are nearly identical, showing emission bands at 490 and 550 nm and a minor band at 600 nm, which are compatible with the characteristic emission of Tb3+. In accordance with these results, stoichiometric terbium fluoride seems to be a promising material for use as an RL sensor for FOD in radiation medicine.

  3. Design of a polarization-insensitive superconducting nanowire single photon detector with high detection efficiency.

    PubMed

    Zheng, Fan; Xu, Ruiying; Zhu, Guanghao; Jin, Biaobing; Kang, Lin; Xu, Weiwei; Chen, Jian; Wu, Peiheng

    2016-01-01

    Superconducting nanowire single photon detectors (SNSPDs) deliver superior performance over their competitors in the near-infrared regime. However, these detectors have an intrinsic polarization dependence on the incident wave because of their one-dimensional meander structure. In this paper, we propose an approach to eliminate the polarization sensitivity of SNSPDs by using near-field optics to increase the absorption of SNSPDs under transverse magnetic (TM) illumination. In addition, an optical cavity is added to our SNSPD to obtain nearly perfect absorption of the incident wave. Numerical simulations show that the maximum absorption of a designed SNSPD can reach 96% at 1550 nm, and indicate that the absorption difference between transverse electric (TE) and TM polarization is less than 0.5% across a wavelength window of 300 nm. Our work provides the first demonstration of the possibility of designing a polarization-insensitive and highly efficient SNSPD without performing device symmetry improvements. PMID:26948672

  4. Design of a polarization-insensitive superconducting nanowire single photon detector with high detection efficiency

    PubMed Central

    Zheng, Fan; Xu, Ruiying; Zhu, Guanghao; Jin, Biaobing; Kang, Lin; Xu, Weiwei; Chen, Jian; Wu, Peiheng

    2016-01-01

    Superconducting nanowire single photon detectors (SNSPDs) deliver superior performance over their competitors in the near-infrared regime. However, these detectors have an intrinsic polarization dependence on the incident wave because of their one-dimensional meander structure. In this paper, we propose an approach to eliminate the polarization sensitivity of SNSPDs by using near-field optics to increase the absorption of SNSPDs under transverse magnetic (TM) illumination. In addition, an optical cavity is added to our SNSPD to obtain nearly perfect absorption of the incident wave. Numerical simulations show that the maximum absorption of a designed SNSPD can reach 96% at 1550 nm, and indicate that the absorption difference between transverse electric (TE) and TM polarization is less than 0.5% across a wavelength window of 300 nm. Our work provides the first demonstration of the possibility of designing a polarization-insensitive and highly efficient SNSPD without performing device symmetry improvements. PMID:26948672

  5. Fluoro Jade-B detection of dying cells in the SVZ and RMS of adult rats after bilateral olfactory bulbectomy.

    PubMed

    Mitrusková, Barbora; Orendácová, Judita; Raceková, Enikö

    2005-12-01

    A novel fluorochrome, Fluoro-Jade B, was used to detect dying precursor cells in the subventricular zone (SVZ) and rostral migratory stream (RMS) of adult rats after bilateral olfactory bulbectomy and in control intact rats. The animals in experimental group were left to survive 3 days and from 3 till 16 months after surgical procedure. 1. In the control animals, Fluoro-Jade B positive cells were visible in the SVZ and within the whole extent of the RMS. The number of Fluoro-Jade B positive cells increased in the elbow in comparison to the rest parts of the RMS. 2. In the experimental animals surviving either 3 days or from 3 till 16 months after bilateral olfactory bulbectomy, Fluoro-Jade B positive cells displayed the similar pattern of distribution as in the control animals. However, some quantitative differences in the labeled cells number along the rostral migratory pathway appeared. 3. The average number of degenerating cells within the control SVZ and RMS was 26.24+/- 0.686. In bulbectomized animals, regardless of survival time, an insignificant increase of Fluoro-Jade B positive cells number occurred. We can conclude that dying of precursor cells is a physiological process running within the SVZ/RMS in both control and experimental animals. Moreover, this physiological process is not influenced by survival period after bilateral olfactory bulbectomy. Our results demonstrate Fluoro-Jade B as a useful marker of dying cells.

  6. Adults' Detection of Deception in Children: Effect of Coaching and Age for Children's True and Fabricated Reports of Injuries.

    PubMed

    Warren, Kelly L; Bakhtiar, Aishah; Mulrooney, Brent; Raynor, Graham; Dodd, Elyse; Peterson, Carole

    2015-01-01

    A total of 1,074 undergraduates judged the truthfulness of children's interviews (from verbatim transcripts) about experiencing injuries serious enough to require hospital emergency room treatment. Ninety-six children (three age groups: 5-7, 8-10, and 11-14 years, 50% girls) were interviewed. At each age, 16 children told truthful accounts of actual injury experiences and 16 fabricated their reports, with half of each group coached by parents for the previous 4 days. Lies by 5- to 7-year-olds, whether coached or not, were detected at above-chance levels. In contrast, 8- to 10-year-olds' accounts that were coached, whether true or not, were more likely to be believed. For 11- to 14-year-olds, adults were less likely to accurately judge lies if they were coached. The believability of children aged 8 or above who were coached to lie is particularly disturbing in light of the finding that participants were more confident in the accuracy of their veracity decisions when judging coached reports. PMID:26549017

  7. Suggestions for improving the efficiency of ground-based neutron monitors for detecting solar neutrons

    NASA Technical Reports Server (NTRS)

    Iucci, N.; Parisi, M.; Signorini, C.; Storini, M.; Villoresi, G.

    1985-01-01

    On the occasion of the June 3, 1982 intense gamma-ray solar flare a significant increase in counting rate due to solar neutrons was observed by the neutron monitors of Junsfraujoch and Lomnicky Stit located at middle latitudes and high altitudes. In spite of a larger detector employed and of the smaller solar zenith angle, the amplitude of the same event observed at Rome was much smaller and the statistical fluctuations of the salactic cosmic ray background higher than the ones registered at the two mountain stations, because of the greater atmospheric depth at which the Rome monitor is located. The effeciency for detecting a solar neutron event by a NM-64 monitor as a function of the Sun zenith angle, atmospheric depth and threshold rigidity of the station was studied.

  8. Functionalization of Polymers with Fluorescent and Neutron Sensitive Groups for Efficient Neutron and Gamma Detection

    NASA Astrophysics Data System (ADS)

    Mahl, Adam; Yemam, Henok; Remedes, Tyler; Stuntz, Jack; Koldemir, Unsal; Sellinger, Alan; Greife, Uwe

    2015-10-01

    This presentation will review the efforts made by an interdisciplinary development project aimed at cost-effective, thermal neutron sensitive, plastic scintillators as part of the communities efforts towards replacing 3He based detectors. Colorado School of Mines researchers with backgrounds in Physics and Chemistry have worked on the incorporation of 10B in plastics through admixture of various commercial and novel dopants developed at CSM. In addition, new fluorescent dopants have been developed for plastic scintillators in an effort towards better understanding quenching effects and scintillator response to thermal neutrons via pulse shape discrimination methods. Results on transparent samples using fluorescent spectroscopy and gamma/neutron excitation will be presented. Funded via Department of Homeland Security - Domestic Nuclear Detection Office.

  9. Preparation TiO2 core-shell nanospheres and application as efficiency drug detection sensor

    PubMed Central

    2014-01-01

    In this paper, we report the facile preparation of monodisperse titanium dioxide-diltiazem/tetrachlorobismuth core-shell nanospheres (TiO2@DTMBi), in which, diltiazem (DTM)/tetrachlorobismuth (BiCl4) complexes were employed as electroactive materials. The morphology, size, formation, and structure of the obtained TiO2@DTMBi spheres were investigated by transmission electron microscopy, scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and X-ray diffraction. The optimal condition of obtained monodisperse 40-nm TiO2@DTMBi spheres was researched. The results of using TiO2@DTMBi nanospheres as proposed drug sensor indicate a wide linear range (10-7 to 10-1 M) and a very low detection limit of 0.20 μg/mL. PMID:25246870

  10. Inhibitory control efficiency in a Piaget-like class-inclusion task in school-age children and adults: a developmental negative priming study.

    PubMed

    Borst, G; Poirel, N; Pineau, A; Cassotti, M; Houdé, O

    2013-07-01

    Most children under 7 years of age presented with 10 daisies and 2 roses fail to indicate that there are more flowers than daisies. Instead of the appropriate comparison of the relative numerosities of the superordinate class (flowers) to its subordinate class (daisies), they perform a direct perceptual comparison of the extensions of the 2 subordinate classes (daisies vs. roses). In our experiment, we investigated whether increasing efficiency in solving the Piagetian class-inclusion task is related to increasing efficiency in the ability to resist (inhibit) this direct comparison of the subordinate classes' extensions. Ten-year-old and young adult participants performed a computerized priming version of a Piaget-like class-inclusion task. The experimental design was such that the misleading perceptual strategy to inhibit on the prime (in which a superordinate class had to be compared with a subordinate class) became a congruent strategy to activate on the probe (in which the two subordinate classes' extensions were directly compared). We found a negative priming effect of 291 ms in children and 129 ms in adults. These results provide evidence for the first time (a) that adults still need to inhibit the comparison of the subordinate classes' extensions in class-inclusion tasks and (b) that the ability to inhibit this heuristic increases with age (resulting in a lower executive cost). Taken together, these findings provide additional support for the neo-Piagetian approach of cognitive development that suggests that the acquisition of increasingly complex knowledge is based on the ability to resist (inhibit) heuristics and previously acquired knowledge. PMID:22889392

  11. Differences in EEG power in young and mature healthy adults during an incidental/spatial learning task are related to age and execution efficiency.

    PubMed

    López-Loeza, Elisa; Rangel-Argueta, Ana Rosa; López-Vázquez, Miguel Ángel; Cervantes, Miguel; Olvera-Cortés, María Esther

    2016-04-01

    The differential characteristics of absolute power in the EEG theta (4-8 Hz) and gamma (30-45 Hz) frequency bands have been analysed in young (18-25 years old, n = 14) and mature adults (45-65 years old, n = 12) during the incidental or intentional behavioural conditions of learning and recalling in a visuospatial task. A printed drawing of a maze including eight figures of common objects in specific placements, solved by connecting its entrance and exit points, allowed the subject's performance efficiency to be measured based on the number, position accuracy and/or identity of incidentally or intentionally learned and remembered objects. Meanwhile, EEG recordings from frontal, parietal and temporal derivations were obtained to determine the power values of the theta (4-8 Hz) and gamma (30-45 Hz) bands for each behavioural condition and derivation. Relative to the young adults, the mature adults generally showed lower absolute theta power values, mainly due to their low theta powers under the basal and incidental learning conditions, and higher absolute gamma power values in the frontal and temporal regions. Furthermore, higher theta band power in the frontal regions was related to higher performance efficiency in both incidental and intentional learning, regardless of the subjects' age. A significant negative correlation between the parameters of individual incidental or intentional learning performance and age was also found. Indeed, a differential accuracy of remembered information seems to be associated with age and incidental or intentional learning/memory testing conditions. These data support an increasing vulnerability of visuospatial learning abilities at mature ages and as ageing progresses.

  12. Differences in EEG power in young and mature healthy adults during an incidental/spatial learning task are related to age and execution efficiency.

    PubMed

    López-Loeza, Elisa; Rangel-Argueta, Ana Rosa; López-Vázquez, Miguel Ángel; Cervantes, Miguel; Olvera-Cortés, María Esther

    2016-04-01

    The differential characteristics of absolute power in the EEG theta (4-8 Hz) and gamma (30-45 Hz) frequency bands have been analysed in young (18-25 years old, n = 14) and mature adults (45-65 years old, n = 12) during the incidental or intentional behavioural conditions of learning and recalling in a visuospatial task. A printed drawing of a maze including eight figures of common objects in specific placements, solved by connecting its entrance and exit points, allowed the subject's performance efficiency to be measured based on the number, position accuracy and/or identity of incidentally or intentionally learned and remembered objects. Meanwhile, EEG recordings from frontal, parietal and temporal derivations were obtained to determine the power values of the theta (4-8 Hz) and gamma (30-45 Hz) bands for each behavioural condition and derivation. Relative to the young adults, the mature adults generally showed lower absolute theta power values, mainly due to their low theta powers under the basal and incidental learning conditions, and higher absolute gamma power values in the frontal and temporal regions. Furthermore, higher theta band power in the frontal regions was related to higher performance efficiency in both incidental and intentional learning, regardless of the subjects' age. A significant negative correlation between the parameters of individual incidental or intentional learning performance and age was also found. Indeed, a differential accuracy of remembered information seems to be associated with age and incidental or intentional learning/memory testing conditions. These data support an increasing vulnerability of visuospatial learning abilities at mature ages and as ageing progresses. PMID:26961695

  13. Inhibitory control efficiency in a Piaget-like class-inclusion task in school-age children and adults: a developmental negative priming study.

    PubMed

    Borst, G; Poirel, N; Pineau, A; Cassotti, M; Houdé, O

    2013-07-01

    Most children under 7 years of age presented with 10 daisies and 2 roses fail to indicate that there are more flowers than daisies. Instead of the appropriate comparison of the relative numerosities of the superordinate class (flowers) to its subordinate class (daisies), they perform a direct perceptual comparison of the extensions of the 2 subordinate classes (daisies vs. roses). In our experiment, we investigated whether increasing efficiency in solving the Piagetian class-inclusion task is related to increasing efficiency in the ability to resist (inhibit) this direct comparison of the subordinate classes' extensions. Ten-year-old and young adult participants performed a computerized priming version of a Piaget-like class-inclusion task. The experimental design was such that the misleading perceptual strategy to inhibit on the prime (in which a superordinate class had to be compared with a subordinate class) became a congruent strategy to activate on the probe (in which the two subordinate classes' extensions were directly compared). We found a negative priming effect of 291 ms in children and 129 ms in adults. These results provide evidence for the first time (a) that adults still need to inhibit the comparison of the subordinate classes' extensions in class-inclusion tasks and (b) that the ability to inhibit this heuristic increases with age (resulting in a lower executive cost). Taken together, these findings provide additional support for the neo-Piagetian approach of cognitive development that suggests that the acquisition of increasingly complex knowledge is based on the ability to resist (inhibit) heuristics and previously acquired knowledge.

  14. JTK_CYCLE: an efficient non-parametric algorithm for detecting rhythmic components in genome-scale datasets

    PubMed Central

    Hughes, Michael E.; Hogenesch, John B.; Kornacker, Karl

    2011-01-01

    Circadian rhythms are oscillations of physiology, behavior, and metabolism that have period lengths of 24 hours. In several model organisms and man, circadian clock genes have been characterized and found to be transcription factors. Because of this, researchers have used microarrays to characterize global regulation of gene expression and algorithmic approaches to detect cycling. Here we present a new algorithm, JTK_CYCLE, designed to efficiently identify and characterize cycling variables in large datasets. Compared to COSOPT and the Fisher’s G test, two commonly used methods for detecting cycling transcripts, JTK_CYCLE distinguishes between rhythmic and non-rhythmic transcripts more reliably and efficiently. We also show that JTK_CYCLE’s increased resistance to outliers results in considerably greater sensitivity and specificity. Moreover, JTK_CYCLE accurately measures the period, phase, and amplitude of cycling transcripts, facilitating downstream analyses. Finally, it is several orders of magnitude faster than COSOPT, making it ideal for large scale data sets. We used JTK_CYCLE to analyze legacy data sets including NIH3T3 cells, which have comparatively low amplitude. JTK_CYCLE’s improved power led to the identification of a novel cluster of RNA-interacting genes whose abundance is under clear circadian regulation. These data suggest that JTK_CYCLE is an ideal tool for identifying and characterizing oscillations in genome-scale datasets. PMID:20876817

  15. A highly efficient urea detection using flower-like zinc oxide nanostructures.

    PubMed

    Tak, Manvi; Gupta, Vinay; Tomar, Monika

    2015-12-01

    A novel matrix based on flower-like zinc oxide nanostructures (ZnONF) has been fabricated using hydrothermal method and exploited successfully for the development of urea biosensor. Urease (Urs) is physically immobilized onto the ZnO nanostructure matrix synthesized over platinized silicon substrate. The surface morphology and crystallographic structure of the as-grown ZnONF have been characterized using a scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques. The fabricated amperometric biosensor (Urs/ZnONF/Pt/Ti/Si) exhibits a linear sensing response towards urea over the concentration range 1.65 mM to 16.50mM with an enhanced sensitivity (~132 μA/mM/cm(2)) and a fast response time of 4s. The relatively low value of Michaelis-Menten constant (Km) of 0.19 mM confirms the high affinity of the immobilized urease on the nanostructured ZnONF surface towards its analyte (urea). The obtained results demonstrate that flower-like ZnO nanostructures serve as a promising matrix for the realization of efficient amperometric urea biosensor with enhanced response characteristics.

  16. Avoiding incidental predation by mammalian herbivores: accurate detection and efficient response in aphids

    NASA Astrophysics Data System (ADS)

    Gish, Moshe; Dafni, Amots; Inbar, Moshe

    2011-09-01

    Mammalian herbivores eat plants that may also provide food and shelter for insects. The direct trophic effect of the browsing and grazing of mammalian herbivory on insects, which is probably prevalent in terrestrial ecosystems, has been mostly neglected by ecologists. We examined how the aphid Uroleucon sonchi L. deals with the danger of incidental predation by mammalian herbivores. We found that most (76%) of the aphids in a colony survive the ingestion of the plant by a feeding herbivore. They do so by sensing the combination of heat and humidity in the herbivore's breath and immediately dropping off the plant in large numbers. Their ability to sense the herbivore's breath or their tendency to drop off the plant weakens as ambient temperature rises. This could indicate a limitation of the aphids' sensory system or an adaptation that enables them to avoid the hostile conditions on a hot ground. Once on the ground, U. sonchi is highly mobile and capable of locating a new host plant by advancing in a pattern that differs significantly from random movement. The accurate and efficient defense mechanism of U. sonchi emphasizes the significance of incidental predation as a danger to plant-dwelling invertebrates.

  17. Visual and efficient immunosensor technique for advancing biomedical applications of quantum dots on Salmonella detection and isolation

    NASA Astrophysics Data System (ADS)

    Tang, Feng; Pang, Dai-Wen; Chen, Zhi; Shao, Jian-Bo; Xiong, Ling-Hong; Xiang, Yan-Ping; Xiong, Yan; Wu, Kai; Ai, Hong-Wu; Zhang, Hui; Zheng, Xiao-Li; Lv, Jing-Rui; Liu, Wei-Yong; Hu, Hong-Bing; Mei, Hong; Zhang, Zhen; Sun, Hong; Xiang, Yun; Sun, Zi-Yong

    2016-02-01

    It is a great challenge in nanotechnology for fluorescent nanobioprobes to be applied to visually detect and directly isolate pathogens in situ. A novel and visual immunosensor technique for efficient detection and isolation of Salmonella was established here by applying fluorescent nanobioprobes on a specially-designed cellulose-based swab (a solid-phase enrichment system). The selective and chromogenic medium used on this swab can achieve the ultrasensitive amplification of target bacteria and form chromogenic colonies in situ based on a simple biochemical reaction. More importantly, because this swab can serve as an attachment site for the targeted pathogens to immobilize and immunologically capture nanobioprobes, our mAb-conjugated QD bioprobes were successfully applied on the solid-phase enrichment system to capture the fluorescence of targeted colonies under a designed excitation light instrument based on blue light-emitting diodes combined with stereomicroscopy or laser scanning confocal microscopy. Compared with the traditional methods using 4-7 days to isolate Salmonella from the bacterial mixture, this method took only 2 days to do this, and the process of initial screening and preliminary diagnosis can be completed in only one and a half days. Furthermore, the limit of detection can reach as low as 101 cells per mL Salmonella on the background of 105 cells per mL non-Salmonella (Escherichia coli, Proteus mirabilis or Citrobacter freundii, respectively) in experimental samples, and even in human anal ones. The visual and efficient immunosensor technique may be proved to be a favorable alternative for screening and isolating Salmonella in a large number of samples related to public health surveillance.It is a great challenge in nanotechnology for fluorescent nanobioprobes to be applied to visually detect and directly isolate pathogens in situ. A novel and visual immunosensor technique for efficient detection and isolation of Salmonella was established here

  18. Enhanced efficiency of a capillary-based biosensor over an optical fiber biosensor for detecting calpastatin.

    PubMed

    Bratcher, C L; Grant, S A; Vassalli, J T; Lorenzen, C L

    2008-06-15

    A capillary-based optical biosensor has been developed to detect calpastatin, an indicator of meat tenderness. Longissimus muscle samples (n=11) were extracted from beef carcasses at 0 and 48h post-mortem. These samples were assayed for calpastatin by traditional laboratory methods and with a newly developed capillary tube biosensor as well as for Warner-Bratzler shear force (WBSF) and crude protein and the responses were compared. Additionally, the response from the capillary-based biosensor was compared to a previously developed optical fiber biosensor. When the 0 and 48h sampling periods were combined, the capillary tube biosensor was moderately accurate in predicting calpastatin activity (R(2)=0.6058). There was less variation in the 0h capillary tube biosensor compared to the 0h pre-column (P=0.006) and post-column optical fiber biosensors (P=0.047), therefore the capillary tube biosensor is a more precise system of measurement. This research further advances the development of a calpastatin biosensor and makes online assessment one step closer to reality.

  19. Efficiency of a rapid test for detection of tetrodotoxin in puffer fish.

    PubMed

    Thattiyaphong, Aree; Unahalekhaka, Jirapa; Mekha, Nanthawan; Nispa, Wansatip; Kluengklangdon, Panawan; Rojanapantip, Laddawan

    2014-01-01

    The selling and importing of puffer fish species and their products was banned in Thailand in 2002, because of possible neurotoxic effects. However, the sale of their flesh is still happening in Thai markets. Standard methods for toxin quantification (HPLC and LC-MS) have significant limitations, therefore a lateral flow, immuno-chromatographic test (TTX-IC) was developed as a tool for rapid detection of toxin. A total of 750 puffer fishes (387 Lagocephalus lunaris(LL), and 363 Lagocephalus spadiceus (LS)) and 100 edible fishes were caught in Thailand from June 2011-February 2012. Screening of TTX from their flesh by TTX-IC revealed that 69 samples (17.8%) of LL possessed TTX at dangerous levels but LS and edible fishes did not. A selected 339 samples were quantified by LC-MS/MS, showing 50 LL possessed TTX at dangerous levels. Comparison of results with LC-MS/MS showed the TTX-IC to have 94.0% sensitivity and 92.4% specificity. The TTX-IC will be a useful tool for TTX screening of a large number of samples, reducing the testing required by LC-MS/MS, thus reducing costs. All positive cases found should be confirmed by standard methods.

  20. DNA aptamer–micelle as an efficient detection/delivery vehicle toward cancer cells

    PubMed Central

    Wu, Yanrong; Sefah, Kwame; Liu, Haipeng; Wang, Ruowen; Tan, Weihong

    2010-01-01

    We report the design of a self-assembled aptamer–micelle nanostructure that achieves selective and strong binding of otherwise low-affinity aptamers at physiological conditions. Specific recognition ability is directly built into the nanostructures. The attachment of a lipid tail onto the end of nucleic acid aptamers provides these unique nanostructures with an internalization pathway. Other merits include: extremely low off rate once bound with target cells, rapid recognition ability with enhanced sensitivity, low critical micelle concentration values, and dual-drug delivery pathways. To prove the potential detection/delivery application of this aptamer–micelle in biological living systems, we mimicked a tumor site in the blood stream by immobilizing tumor cells onto the surface of a flow channel device. Flushing the aptamer–micelles through the channel demonstrated their selective recognition ability under flow circulation in human whole-blood sample. The aptamer–micelles show great dynamic specificity in flow channel systems that mimic drug delivery in the blood system. Therefore, our DNA aptamer–micelle assembly has shown high potential for cancer cell recognition and for in vivo drug delivery applications. PMID:20080797

  1. Thermostability of firefly luciferases affects efficiency of detection by in vivo bioluminescence.

    PubMed

    Baggett, Brenda; Roy, Rupali; Momen, Shafinaz; Morgan, Sherif; Tisi, Laurence; Morse, David; Gillies, Robert J

    2004-10-01

    Luciferase from the North American firefly (Photinis pyralis) is a useful reporter gene in vivo, allowing noninvasive imaging of tumor growth, metastasis, gene transfer, drug treatment, and gene expression. Luciferase is heat labile with an in vitro halflife of approximately 3 min at 37 degrees C. We have characterized wild type and six thermostabilized mutant luciferases. In vitro, mutants showed half-lives between 2- and 25-fold higher than wild type. Luciferase transfected mammalian cells were used to determine in vivo half-lives following cycloheximide inhibition of de novo protein synthesis. This showed increased in vivo thermostability in both wild-type and mutant luciferases. This may be due to a variety of factors, including chaperone activity, as steady-state luciferase levels were reduced by geldanamycin, an Hsp90 inhibitor. Mice inoculated with tumor cells stably transfected with mutant or wild-type luciferases were imaged. Increased light production and sensitivity were observed in the tumors bearing thermostable luciferase. Thermostable proteins increase imaging sensitivity. Presumably, as more active protein accumulates, detection is possible from a smaller number of mutant transfected cells compared to wild-type transfected cells.

  2. Narrowband light detection via internal quantum efficiency manipulation of organic photodiodes

    NASA Astrophysics Data System (ADS)

    Armin, Ardalan; Jansen-van Vuuren, Ross D.; Kopidakis, Nikos; Burn, Paul L.; Meredith, Paul

    2015-02-01

    Spectrally selective light detection is vital for full-colour and near-infrared (NIR) imaging and machine vision. This is not possible with traditional broadband-absorbing inorganic semiconductors without input filtering, and is yet to be achieved for narrowband absorbing organic semiconductors. We demonstrate the first sub-100 nm full-width-at-half-maximum visible-blind red and NIR photodetectors with state-of-the-art performance across critical response metrics. These devices are based on organic photodiodes with optically thick junctions. Paradoxically, we use broadband-absorbing organic semiconductors and utilize the electro-optical properties of the junction to create the narrowest NIR-band photoresponses yet demonstrated. In this context, these photodiodes outperform the encumbent technology (input filtered inorganic semiconductor diodes) and emerging technologies such as narrow absorber organic semiconductors or quantum nanocrystals. The design concept allows for response tuning and is generic for other spectral windows. Furthermore, it is material-agnostic and applicable to other disordered and polycrystalline semiconductors.

  3. Efficient detection of wound-bed and peripheral skin with statistical colour models.

    PubMed

    Veredas, Francisco J; Mesa, Héctor; Morente, Laura

    2015-04-01

    A pressure ulcer is a clinical pathology of localised damage to the skin and underlying tissue caused by pressure, shear or friction. Reliable diagnosis supported by precise wound evaluation is crucial in order to success on treatment decisions. This paper presents a computer-vision approach to wound-area detection based on statistical colour models. Starting with a training set consisting of 113 real wound images, colour histogram models are created for four different tissue types. Back-projections of colour pixels on those histogram models are used, from a Bayesian perspective, to get an estimate of the posterior probability of a pixel to belong to any of those tissue classes. Performance measures obtained from contingency tables based on a gold standard of segmented images supplied by experts have been used for model selection. The resulting fitted model has been validated on a training set consisting of 322 wound images manually segmented and labelled by expert clinicians. The final fitted segmentation model shows robustness and gives high mean performance rates [(AUC: .9426 (SD .0563); accuracy: .8777 (SD .0799); F-score: 0.7389 (SD .1550); Cohen's kappa: .6585 (SD .1787)] when segmenting significant wound areas that include healing tissues.

  4. Visual and efficient immunosensor technique for advancing biomedical applications of quantum dots on Salmonella detection and isolation.

    PubMed

    Tang, Feng; Pang, Dai-Wen; Chen, Zhi; Shao, Jian-Bo; Xiong, Ling-Hong; Xiang, Yan-Ping; Xiong, Yan; Wu, Kai; Ai, Hong-Wu; Zhang, Hui; Zheng, Xiao-Li; Lv, Jing-Rui; Liu, Wei-Yong; Hu, Hong-Bing; Mei, Hong; Zhang, Zhen; Sun, Hong; Xiang, Yun; Sun, Zi-Yong

    2016-02-28

    It is a great challenge in nanotechnology for fluorescent nanobioprobes to be applied to visually detect and directly isolate pathogens in situ. A novel and visual immunosensor technique for efficient detection and isolation of Salmonella was established here by applying fluorescent nanobioprobes on a specially-designed cellulose-based swab (a solid-phase enrichment system). The selective and chromogenic medium used on this swab can achieve the ultrasensitive amplification of target bacteria and form chromogenic colonies in situ based on a simple biochemical reaction. More importantly, because this swab can serve as an attachment site for the targeted pathogens to immobilize and immunologically capture nanobioprobes, our mAb-conjugated QD bioprobes were successfully applied on the solid-phase enrichment system to capture the fluorescence of targeted colonies under a designed excitation light instrument based on blue light-emitting diodes combined with stereomicroscopy or laser scanning confocal microscopy. Compared with the traditional methods using 4-7 days to isolate Salmonella from the bacterial mixture, this method took only 2 days to do this, and the process of initial screening and preliminary diagnosis can be completed in only one and a half days. Furthermore, the limit of detection can reach as low as 10(1) cells per mL Salmonella on the background of 10(5) cells per mL non-Salmonella (Escherichia coli, Proteus mirabilis or Citrobacter freundii, respectively) in experimental samples, and even in human anal ones. The visual and efficient immunosensor technique may be proved to be a favorable alternative for screening and isolating Salmonella in a large number of samples related to public health surveillance. PMID:26853517

  5. Novel methods to enhance single strand conformation polymorphism (SSCP) senstivity and efficiency: Application to mutation detection in cystic fibrosis (CF)

    SciTech Connect

    Hagstrom, D.J.; Snow, K.; Yuan, Z.; Thibodeau, S.N.

    1994-09-01

    For single gene defects in which there are a variety of mutations with significant frequencies, it is a challenge to find an efficient and sensitive method for mutation detection. For example, although 70% to 75% of CF chromosomes in a North American Caucasian population have the mutation {delta}F508, more than 400 mutations (mostly single base pair substitutions) are represented on the remaining chromosomes. SSCP analysis is a relatively straightforward procedure and therefore suitable for routine use in a clinical laboratory. However, previous reports have demonstrated suboptimal sensitivity rates in screening for mutations. We have developed a novel set of conditions which greatly enhances sensitivity and efficiency of SSCP. Our protocol incorporates multiplex PCR, stepping of wattages during electrophoresis and increased salt concentration at the anode relative to the gel. To screen for mutations in the CFTR gene, three multiplex PCR reactions are performed using identical thermocycler parameters. Sizes of PCR products range from 441 bp to 196 bp: size differences of > 30 bp are necessary to ensure separation during electrophoresis. All PCR products are separated by electrophoresis at room temperature on a single gel containing 8% (37.5:1) polyacrylamide, 5% glycerol and 1x TBE. Using an anode buffer with increased salt (2x TBE) sharpens smaller sized bands, and stepping watts from 5W to 20W during electrophoresis enhances sensitivity. Positive controls were used to demonstrate that mutations could be detected. Other mutations or polymorphisms were verified by cycle sequencing of PCR products or by alternative PCR-based assays for the more common mutations. Thus, using 3 PCR reactions per patient and one gel condition, we are able to achieve a CF mutation detection rate of approximately 90% in a North American Caucasian population.

  6. Optimization of high-efficiency hemodialysis by detection and correction of fistula dysfunction.

    PubMed

    Windus, D W; Audrain, J; Vanderson, R; Jendrisak, M D; Picus, D; Delmez, J A

    1990-08-01

    Recirculation studies were performed in 103 patients treated with high-efficiency dialysis over a 14 month period. Fistulograms were performed on 22 out of 25 patients with greater than 0.15 fractional recirculation at a 400 ml/minute blood pump setting. Clinically significant abnormalities were found in 82% (N = 18) and treated in 17. Two patients had second episodes of elevated recirculations and were treated again within the period of follow-up. Treatment with angioplasty (N = 11) or surgical revision (N = 8) resulted in a fall in recirculation from 0.33 +/- 0.04 to 0.12 +/- 0.02 (P = 0.001). The fractional reduction of urea clearance due to recirculation fell from 0.20 +/- 0.03 to 0.08 +/- 0.02 (P = 0.001) and the effective urea clearance of the dialysis treatment rose by 16% from 193 +/- 7 ml/min to 224 +/- 6 ml/min (P = 0.001). Pre-dialysis BUN fell from 72 +/- 4 mg/100 ml to 62 +/- 3 mg/100 ml (P = 0.012). There was no correlation between venous pressure (VP) at 400 ml/min blood pump setting and recirculation (R2 = 0.04), although VP changed significantly comparing values before and after fistula repair (211 +/- 10 vs. 186 +/- 7 mm Hg, P = 0.012). Venous pressures in 20 of the patients in our dialysis unit with recirculations of less than 0.10 were 201 +/- 6 mm Hg (P = NS compared to patients with recirculation greater than or equal to 0.15 at 400 ml/min blood flow).(ABSTRACT TRUNCATED AT 250 WORDS)

  7. The efficiency of fMRI region of interest analysis methods for detecting group differences

    PubMed Central

    Hutchison, Joanna L.; Hubbard, Nicholas A.; Brigante, Ryan M.; Turner, Monroe; Sandoval, Traci I.; Hillis, G. Andrew J.; Weaver, Travis; Rypma, Bart

    2014-01-01

    Background Using a standard space brain template is an efficient way of determining region-of-interest (ROI) boundaries for functional magnetic resonance imaging (fMRI) data analyses. However, ROIs based on landmarks on subject-specific (i.e., native space) brain surfaces are anatomically accurate and probably best reflect the regional blood oxygen level dependent (BOLD) response for the individual. Unfortunately, accurate native space ROIs are often time-intensive to delineate even when using automated methods. New Method We compared analyses of group differences when using standard versus native space ROIs using both volume and surface-based analyses. Collegiate and military-veteran participants completed a button press task and a digit-symbol verification task during fMRI acquisition. Data were analyzed within ROIs representing left and right motor and prefrontal cortices, in native and standard space. Volume and surface-based analysis results were also compared using both functional (i.e., percent signal change) and structural (i.e., voxel or node count) approaches. Results and Comparison with Existing Method(s) Results suggest that transformation into standard space can affect the outcome of structural and functional analyses (inflating/minimizing differences, based on cortical geography), and these transformations can affect conclusions regarding group differences with volumetric data. Conclusions Caution is advised when applying standard space ROIs to volumetric fMRI data. However, volumetric analyses show group differences and are appropriate in circumstances when time is limited. Surface-based analyses using functional ROIs generated the greatest group differences and were less susceptible to differences between native and standard space. We conclude that surface-based analyses are preferable with adequate time and computing resources. PMID:24487017

  8. Ultrarapid and ultrasensitive electrical detection of proteins in a three-dimensional biosensor with high capture efficiency.

    PubMed

    Kim, Bo-Yeong; Sohn, Il-Yung; Lee, Doowon; Han, Gill Sang; Lee, Won-Il; Jung, Hyun Suk; Lee, Nae-Eung

    2015-06-01

    The realization of a high-throughput biosensor platform with ultrarapid detection of biomolecular interactions and an ultralow limit of detection in the femtomolar (fM) range or below has been retarded due to sluggish binding kinetics caused by the scarcity of probe molecules on the nanostructures and/or limited mass transport. Here, as a new method for the highly efficient capture of biomolecules at extremely low concentration, we tested a three-dimensional (3D) platform of a bioelectronic field-effect transistor (bio-FET) with vertically aligned and highly dense one-dimensional (1D) ZnO nanorods (NRs) as a sensing surface capped by an ultrathin TiO2 layer for improved electrolytic stability on a chemical-vapor-deposited graphene (Gr) channel. The ultrarapid detection capability with a very fast response time (∼1 min) at the fM level of proteins in the proposed 3D bio-FET is primarily attributed to the fast binding kinetics of the probe-target proteins due to the small diffusion length of the target molecules to reach the sensor surface and the substantial number of probe molecules available on the largely increased surface area of the vertical ZnO NRs. This new 3D electrical biosensor platform can be easily extended to other electrochemical nanobiosensors and has great potential for practical applications in miniaturized biosensor integrated systems. PMID:25965056

  9. Development of High Quantum Efficiency UV/Blue Photocathode Epitaxial Semiconductor Heterostructures for Scintillation and Cherenkov Radiation Detection

    NASA Technical Reports Server (NTRS)

    Leopold, Daniel J.

    2002-01-01

    The primary goal of this research project was to further extend the use of advanced heteroepitaxial-semiconductor crystal growth techniques such as molecular beam epitaxy (MBE) and to demonstrate significant gains in UV/blue photonic detection by designing and fabricating atomically-tailored heteroepitaxial GaAlN/GaInN photocathode device structures. This NASA Explorer technology research program has focused on the development of photocathodes for Cherenkov and scintillation radiation detection. Support from the program allowed us to enhance our MBE system to include a nitrogen plasma source and a magnetic bearing turbomolecular pump for delivery and removal of high purity atomic nitrogen during GaAlN/GaInN film growth. Under this program we have also designed, built and incorporated a cesium activation stage. In addition, a connected UHV chamber with photocathode transfer/positioner components as well as a hybrid phototube stage was designed and built to make in-situ quantum efficiency measurements without ever having to remove the photocathodes from UHV conditions. Thus we have constructed a system with the capability to couple atomically-tailored MBE-grown photocathode heterostructures with real high gain readout devices for single photon detection evaluation.

  10. Peptide-linked molecular beacons for efficient delivery and rapid mRNA detection in living cells.

    PubMed

    Nitin, Nitin; Santangelo, Philip J; Kim, Gloria; Nie, Shuming; Bao, Gang

    2004-01-01

    Real-time visualization of specific endogenous mRNA expression in vivo has the potential to revolutionize medical diagnosis, drug discovery, developmental and molecular biology. However, conventional liposome- or dendrimer-based cellular delivery of molecular probes is inefficient, slow, and often detrimental to the probes. Here we demonstrate the rapid and sensitive detection of RNA in living cells using peptide-linked molecular beacons that possess self-delivery, targeting and reporting functions. We conjugated the TAT peptide to molecular beacons using three different linkages and demonstrated that, at relatively low concentrations, these molecular beacon constructs were internalized into living cells within 30 min with nearly 100% efficiency. Further, peptide-based delivery did not interfere with either specific targeting by or hybridization-induced fluorescence of the probes. We could therefore detect human GAPDH and survivin mRNAs in living cells fluorescently, revealing intriguing intracellular localization patterns of mRNA. We clearly demonstrated that cellular delivery of molecular beacons using the peptide-based approach has far better performance compared with conventional transfection methods. The peptide-linked molecular beacons approach promises to open new and exciting opportunities in sensitive gene detection and quantification in vivo.

  11. An artificial HSE promoter for efficient and selective detection of heat shock pathway activity.

    PubMed

    Ortner, Viktoria; Ludwig, Alfred; Riegel, Elisabeth; Dunzinger, Sarah; Czerny, Thomas

    2015-03-01

    Detection of cellular stress is of major importance for the survival of cells. During evolution, a network of stress pathways developed, with the heat shock (HS) response playing a major role. The key transcription factor mediating HS signalling activity in mammalian cells is the HS factor HSF1. When activated it binds to the heat shock elements (HSE) in the promoters of target genes like heat shock protein (HSP) genes. They are induced by HSF1 but in addition they integrate multiple signals from different stress pathways. Here, we developed an artificial promoter consisting only of HSEs and therefore selectively reacting to HSF-mediated pathway activation. The promoter is highly inducible but has an extreme low basal level. Direct comparison with the HSPA1A promoter activity indicates that heat-dependent expression can be fully recapitulated by isolated HSEs in human cells. Using this sensitive reporter, we measured the HS response for different temperatures and exposure times. In particular, long heat induction times of 1 or 2 h were compared with short heat durations down to 1 min, conditions typical for burn injuries. We found similar responses to both long and short heat durations but at completely different temperatures. Exposure times of 2 h result in pathway activation at 41 to 44 °C, whereas heat pulses of 1 min lead to a maximum HS response between 47 and 50 °C. The results suggest that the HS response is initiated by a combination of temperature and exposure time but not by a certain threshold temperature.

  12. Gap detection in school-age children and adults: Effects of inherent envelope modulation and the availability of cues across frequency

    PubMed Central

    Buss, Emily; Hall, Joseph W.; Porter, Heather; Grose, John H.

    2014-01-01

    Purpose The present study evaluated the effects of inherent envelope modulation and the availability of cues across frequency on behavioral gap detection with noise-band stimuli in school-age children. Methods Listeners were normal-hearing adults and 5.2- to 15.6-year-olds. Stimuli were continuous bands of noise centered on 2000 Hz, either 1000 or 25 Hz wide. In addition to Gaussian noise at these bandwidths, there were conditions using 25-Hz-wide noise bands modified to either accentuate or minimize inherent envelope modulation (staccato and low-fluctuation noise, respectively). Results Within the 25-Hz-wide conditions, adults’ gap detection thresholds were highest in the staccato, lower in the Gaussian, and lowest in the low-fluctuation noise. Similar trends were evident in children’s thresholds, although inherent envelope modulation had a smaller effect on children than adults. Whereas adults’ thresholds were comparable for the 1000-Hz-wide Gaussian and 25-Hz-wide low-fluctuation stimulus, children’s performance converged on adults’ at a younger age for the 1000-Hz-wide Gaussian stimulus. Conclusions Results are consistent with the idea that children are less susceptible to the disruptive effects of inherent envelope modulation than adults when detecting a gap in a narrowband noise. Further, the ability to use spectrally distributed gap detection cues appears to mature relatively early in childhood. PMID:24686553

  13. Health and Quality of Life Perception in Older Adults: The Joint Role of Cognitive Efficiency and Functional Mobility

    PubMed Central

    Forte, Roberta; Boreham, Colin A.G.; De Vito, Giuseppe; Pesce, Caterina

    2015-01-01

    Cognitive and mobility functions are involved in health-related quality of life (HRQoL). The present cross-sectional study aimed at investigating what facets of efficient cognition and functional mobility interactively contribute to mental and physical HRQoL. Fifty-six healthy older individuals (aged 65–75 years) were evaluated for mental and physical HRQoL, core cognitive executive functions (inhibition, working memory, and cognitive flexibility), and functional mobility (walking) under single and dual task conditions. Multiple regression analyses were run to verify which core executive functions predicted mental and physical HRQoL and whether the ability to perform complex (dual) walking tasks moderated such association. Inhibitory efficiency and the ability to perform physical-mental dual tasks interactively predicted mental HRQoL, whereas cognitive flexibility and the ability to perform physical dual tasks interactively predicted physical HRQoL. Different core executive functions seem relevant for mental and physical HRQoL. Executive function efficiency seems to translate into HRQoL perception when coupled with tangible experience of the ability to walk under dual task conditions that mirror everyday life demands. Implications of these results for supporting the perception of mental and physical quality of life at advanced age are discussed, suggesting the usefulness of multicomponent interventions and environments conducive to walking that jointly aid successful cognitive aging and functional mobility. PMID:26378556

  14. Reliability and Validity of the SPAID-G Checklist for Detecting Psychiatric Disorders in Adults with Intellectual Disability

    ERIC Educational Resources Information Center

    Bertelli, Marco; Scuticchio, Daniela; Ferrandi, Angela, Lassi, Stefano; Mango, Francesco; Ciavatta, Claudio; Porcelli, Cesare; Bianco, Annamaria; Monchieri, Sergio

    2012-01-01

    SPAID (Psychiatric Instrument for the Intellectually Disabled Adult) is the first Italian tool-package for carrying out psychiatric diagnosis in adults with Intellectual Disabilities (ID). It includes the "G" form, for general diagnostic orientation, and specific checklists for all groups of syndromes stated by the available classification…

  15. Nanoscale Au-In alloy-oxide core-shell particles as electrocatalysts for efficient hydroquinone detection

    SciTech Connect

    Sutter, E.; Tong, X.; Medina-Plaza, C.; Rodriguez-Mendez, M. L.; Sutter, P.

    2015-10-09

    The presence of hydroquinone (HQ), a phenol ubiquitous in nature and widely used in industry, needs to be monitored because of its toxicity to the environment. Here we demonstrate efficient detection of HQ using simple, fast, and noninvasive electrochemical measurements on indium tin oxide (ITO) electrodes modified with nanoparticles comprising bimetallic Au–In cores and mixed Au–In oxide shells. Whereas bare ITO electrodes show very low activity for the detection of HQ, their modification with Au–In core–shell nanoparticles induces a pronounced shift of the oxidation peak to lower potentials, i.e., facilitated oxidation. The response of the different electrodes was correlated with the initial composition of the bimetallic nanoparticle cores, which in turn determined the amount of Au and In stabilized on the surface of the amorphous Au–In oxide shells available for the electrochemical reaction. While adding core–shell nanostructures with different compositions of the alloy core facilitates the electrocatalytic (reduction-) oxidation of HQ, the activity is highest for particles with AuIn cores (i.e., a Au:In ratio of 1). This optimal system is found to follow a single pathway, the two-electron oxidation of the quinone–hydroquinone couple, which gives rise to high oxidation peaks and is most effective in facilitating the electrode-to-analyte charge transfer and thus detection. The limits of detection (LOD) decreased when increasing the amount of Au exposed on the surface of the amorphous Au–In oxide shells. As a result the LODs were in the range of 10–5 – 10–6 M and were lower than those obtained using bulk Au.

  16. Nanoscale Au-In alloy-oxide core-shell particles as electrocatalysts for efficient hydroquinone detection

    DOE PAGES

    Sutter, E.; Tong, X.; Medina-Plaza, C.; Rodriguez-Mendez, M. L.; Sutter, P.

    2015-10-09

    The presence of hydroquinone (HQ), a phenol ubiquitous in nature and widely used in industry, needs to be monitored because of its toxicity to the environment. Here we demonstrate efficient detection of HQ using simple, fast, and noninvasive electrochemical measurements on indium tin oxide (ITO) electrodes modified with nanoparticles comprising bimetallic Au–In cores and mixed Au–In oxide shells. Whereas bare ITO electrodes show very low activity for the detection of HQ, their modification with Au–In core–shell nanoparticles induces a pronounced shift of the oxidation peak to lower potentials, i.e., facilitated oxidation. The response of the different electrodes was correlated withmore » the initial composition of the bimetallic nanoparticle cores, which in turn determined the amount of Au and In stabilized on the surface of the amorphous Au–In oxide shells available for the electrochemical reaction. While adding core–shell nanostructures with different compositions of the alloy core facilitates the electrocatalytic (reduction-) oxidation of HQ, the activity is highest for particles with AuIn cores (i.e., a Au:In ratio of 1). This optimal system is found to follow a single pathway, the two-electron oxidation of the quinone–hydroquinone couple, which gives rise to high oxidation peaks and is most effective in facilitating the electrode-to-analyte charge transfer and thus detection. The limits of detection (LOD) decreased when increasing the amount of Au exposed on the surface of the amorphous Au–In oxide shells. As a result the LODs were in the range of 10–5 – 10–6 M and were lower than those obtained using bulk Au.« less

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

    NASA Astrophysics Data System (ADS)

    Chronopoulos, Andreas E.; Apostolatos, Theocharis A.

    2001-08-01

    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 post1.5-Newtonian family of templates on detecting post2-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 post1.5-Newtonian family of templates happens to be more economical for detecting post2-Newtonian signals than the perfectly accurate post2-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 post1.5-Newtonian family of templates more favorable for detecting

  18. The development of an efficient and rapid enzyme linked fluorescent assay method for the detection of Listeria spp. from foods.

    PubMed

    Sewell, A M; Warburton, D W; Boville, A; Daley, E F; Mullen, K

    2003-03-15

    Conventional isolation methods, including the Health Products and Food Branch (HPFB), Health Canada method used for the isolation and identification of Listeria species and Listeria monocytogenes from foods and environmental samples, can take a week or more to complete and are usually labor-intensive. This has led to the development of various rapid methods which attempt to generate results comparable to standard methods but in a reduced time-frame with less hands-on operation. Our previous work with rapid detection systems indicated that the recommended enrichment protocols failed to grow the Listeria to detectable levels in a reliable and consistent manner. In the present study, a novel enrichment protocol is described and consists of samples being pre-enriched in Palcam broth (incubated at 35 degrees C for 26 h), enriched in UVM 2 (30 degrees C for 26 h) and then plated and analysed by a rapid detection kit, with results being generated after 52 h of incubation. In total, 200 naturally contaminated samples were analysed by both the HPFB standard method and the Palcam method. The results showed that the Palcam method is comparable to the HPFB method. Further analysis involved a rapid detection system, which applies ELISA techniques and automation in an enzyme-linked fluorescent assay (ELFA) system. This system, referred to as the Vitek Immuno Diagnostic Assay System or VIDAS, can identify Listeria to the genus or species (L. monocytogenes) level. In this comparison, an additional 324 naturally contaminated samples were analysed by both the Palcam and ELFA methods. The sensitivity and specificity of the ELFA method were 98.1% and 97.0%, respectively, while the efficiency was 97.5%. False-negative and false-positive rates were 1.9% and 3.0%, respectively. These results show that the ELFA method (when using the Palcam method for pre- and secondary enrichment) was efficient and gave reliable results after 52 h of incubation, and met Health Canada's criteria for

  19. Establishment of a short-term, in vivo screening method for detecting chemicals with juvenile hormone activity using adult Daphnia magna.

    PubMed

    Abe, Ryoko; Watanabe, Haruna; Yamamuro, Masumi; Iguchi, Taisen; Tatarazako, Norihisa

    2015-01-01

    Juvenile hormone (JH) and JH agonists have been shown to induce male offspring production in various daphnids, including Daphnia magna using OECD TG211. The critical period (about 1h) for JH action on ova in the parent's ovary to induce male offspring is existing at 7-8h later from ovulation. Therefore, we considered that adult D. magna could be used to produce a short-term screening method for detecting JH analogs. Using this method, we successfully demonstrated male offspring induction in the second broods after exposure to JH or JH agonists. After investigating the exposure time, the number of repetitions and the exposure concentration, we established a short-term, in vivo screening method for detecting JH analogs using adult D. magna. We examined positive and negative control chemicals using a previously developed method and verified the validity of our new testing method.

  20. Time-resolved singlet-oxygen luminescence detection with an efficient and practical semiconductor single-photon detector

    PubMed Central

    Boso, Gianluca; Ke, Damei; Korzh, Boris; Bouilloux, Jordan; Lange, Norbert; Zbinden, Hugo

    2015-01-01

    In clinical applications, such as PhotoDynamic Therapy, direct singlet-oxygen detection through its luminescence in the near-infrared range (1270 nm) has been a challenging task due to its low emission probability and the lack of suitable single-photon detectors. Here, we propose a practical setup based on a negative-feedback avalanche diode detector that is a viable alternative to the current state-of-the art for different clinical scenarios, especially where geometric collection efficiency is limited (e.g. fiber-based systems, confocal microscopy, scanning systems etc.). The proposed setup is characterized with Rose Bengal as a standard photosensitizer and it is used to measure the singlet-oxygen quantum yield of a new set of photosensitizers for site-selective photodynamic therapy. PMID:26819830

  1. Design of the Neuro-ECAT: A high-resolution, high efficiency positron tomography for imaging the adult head or infant torso

    SciTech Connect

    Williams, C.W.; Burgiss, S.G.; Burke, M.R.; Crabtree, M.C.; Hoffman, E.J.; Keyser, R.M.; Phelps, M.E.

    1981-04-01

    The Neuro-ECAT scanner is a positron emission tomograph designed for high resolution cross-sectional imaging of the adult human head, or the complete torso of a child or small animal. The Neuro-ECAT scanner performs both rectilinear and tomographic scans, in both transmission and emission modes. There are three detector planes, producing five images. Each detector plane contains 88 bismuth germanate detectors, arranged in an octagonal array of 11 detectors per bank. Retained and electrically operated shadow shields provide two choices of reconstructed tomographic resolution, nominally 8.0 and 10.5 mm. Interplane septa, also retained and electrically operated, may be inserted between the detector planes for low noise, highly quantitative measurements, or moved aside for high efficiency scanning of low activity levels. The paper presents the Neuro-ECAT scanner design criteria and a description of the scanner. Data from phantom studies are presented to illustrate system performance.

  2. Evaluation of the efficiency of biofield diagnostic system in breast cancer detection using clinical study results and classifiers.

    PubMed

    Subbhuraam, Vinitha Sree; Ng, E Y K; Kaw, G; Acharya U, Rajendra; Chong, B K

    2012-02-01

    The division of breast cancer cells results in regions of electrical depolarisation within the breast. These regions extend to the skin surface from where diagnostic information can be obtained through measurements of the skin surface electropotentials using sensors. This technique is used by the Biofield Diagnostic System (BDS) to detect the presence of malignancy. This paper evaluates the efficiency of BDS in breast cancer detection and also evaluates the use of classifiers for improving the accuracy of BDS. 182 women scheduled for either mammography or ultrasound or both tests participated in the BDS clinical study conducted at Tan Tock Seng hospital, Singapore. Using the BDS index obtained from the BDS examination and the level of suspicion score obtained from mammography/ultrasound results, the final BDS result was deciphered. BDS demonstrated high values for sensitivity (96.23%), specificity (93.80%), and accuracy (94.51%). Also, we have studied the performance of five supervised learning based classifiers (back propagation network, probabilistic neural network, linear discriminant analysis, support vector machines, and a fuzzy classifier), by feeding selected features from the collected dataset. The clinical study results show that BDS can help physicians to differentiate benign and malignant breast lesions, and thereby, aid in making better biopsy recommendations. PMID:20703753

  3. Evaluation of the efficiency of biofield diagnostic system in breast cancer detection using clinical study results and classifiers.

    PubMed

    Subbhuraam, Vinitha Sree; Ng, E Y K; Kaw, G; Acharya U, Rajendra; Chong, B K

    2012-02-01

    The division of breast cancer cells results in regions of electrical depolarisation within the breast. These regions extend to the skin surface from where diagnostic information can be obtained through measurements of the skin surface electropotentials using sensors. This technique is used by the Biofield Diagnostic System (BDS) to detect the presence of malignancy. This paper evaluates the efficiency of BDS in breast cancer detection and also evaluates the use of classifiers for improving the accuracy of BDS. 182 women scheduled for either mammography or ultrasound or both tests participated in the BDS clinical study conducted at Tan Tock Seng hospital, Singapore. Using the BDS index obtained from the BDS examination and the level of suspicion score obtained from mammography/ultrasound results, the final BDS result was deciphered. BDS demonstrated high values for sensitivity (96.23%), specificity (93.80%), and accuracy (94.51%). Also, we have studied the performance of five supervised learning based classifiers (back propagation network, probabilistic neural network, linear discriminant analysis, support vector machines, and a fuzzy classifier), by feeding selected features from the collected dataset. The clinical study results show that BDS can help physicians to differentiate benign and malignant breast lesions, and thereby, aid in making better biopsy recommendations.

  4. Optomagnetic read-out enables easy, rapid, and cost-efficient qualitative biplex detection of bacterial DNA sequences.

    PubMed

    Bejhed, Rebecca S; Zardán Gómez de la Torre, Teresa; Svedlindh, Peter; Strömberg, Mattias

    2015-03-01

    There is an increasing need to develop novel bioassay methods for low-cost, rapid, and easy-to-use multiplex detection of pathogens in various fields ranging from human infectious disease diagnosis, drinking water quality control, to food safety applications. Due to their unique advantages, magnetic and optomagnetic bioassay principles are particularly promising for biodetection platforms that will be used in developing countries. In this paper, an optomagnetic method for rapid and cost-efficient qualitative biplex detection of bacterial DNA sequences is demonstrated. Within less than two hours, the assay gives an answer to whether none, both, or only one of the bacterial DNA sequences is present in the sample. The assay relies on hybridization of oligonucleotide-functionalized magnetic nanobeads of two different sizes to rolling circle amplification (RCA) products originating from two different bacterial targets. The different bead sizes are equipped with different oligonucleotide probes, complementary to only one of the RCA products, and the read-out is carried out in the same sample volume. In an optomagnetic setup, the frequency modulation of transmitted laser light in response to an applied AC magnetic field is measured. The presented methodology is potentially interesting for low-cost screening of pathogens relating to both human and veterinary medicine in resource-poor regions of the world. PMID:25512105

  5. A novel real-time resource efficient implementation of Sobel operator-based edge detection on FPGA

    NASA Astrophysics Data System (ADS)

    Singh, Sanjay; Saini, Anil K.; Saini, Ravi; Mandal, A. S.; Shekhar, Chandra; Vohra, Anil

    2014-12-01

    A new resource efficient FPGA-based hardware architecture for real-time edge detection using Sobel operator for video surveillance applications has been proposed. The choice of Sobel operator is due to its property to counteract the noise sensitivity of the simple gradient operator. FPGA is chosen for this implementation due to its flexibility to provide the possibility to perform algorithmic changes in later stage of the system development and its capability to provide real-time performance, hard to achieve with general purpose processor or digital signal processor, while limiting the extensive design work, time and cost required for application specific integrated circuit. The proposed architecture uses single processing element for both horizontal and vertical gradient computation for Sobel operator and utilised approximately 38% less FPGA resources as compared to standard Sobel edge detection architecture while maintaining real-time frame rates for high definition videos (1920 × 1080 image sizes). The complete system is implemented on Xilinx ML510 (Virtex-5 FX130T) FPGA board.

  6. Optomagnetic read-out enables easy, rapid, and cost-efficient qualitative biplex detection of bacterial DNA sequences

    PubMed Central

    Bejhed, Rebecca S; Zardán Gómez de la Torre, Teresa; Svedlindh, Peter; Strömberg, Mattias

    2015-01-01

    There is an increasing need to develop novel bioassay methods for low-cost, rapid, and easy-to-use multiplex detection of pathogens in various fields ranging from human infectious disease diagnosis, drinking water quality control, to food safety applications. Due to their unique advantages, magnetic and optomagnetic bioassay principles are particularly promising for biodetection platforms that will be used in developing countries. In this paper, an optomagnetic method for rapid and cost-efficient qualitative biplex detection of bacterial DNA sequences is demonstrated. Within less than two hours, the assay gives an answer to whether none, both, or only one of the bacterial DNA sequences is present in the sample. The assay relies on hybridization of oligonucleotide-functionalized magnetic nanobeads of two different sizes to rolling circle amplification (RCA) products originating from two different bacterial targets. The different bead sizes are equipped with different oligonucleotide probes, complementary to only one of the RCA products, and the read-out is carried out in the same sample volume. In an optomagnetic setup, the frequency modulation of transmitted laser light in response to an applied AC magnetic field is measured. The presented methodology is potentially interesting for low-cost screening of pathogens relating to both human and veterinary medicine in resource-poor regions of the world. PMID:25512105

  7. Optomagnetic read-out enables easy, rapid, and cost-efficient qualitative biplex detection of bacterial DNA sequences.

    PubMed

    Bejhed, Rebecca S; Zardán Gómez de la Torre, Teresa; Svedlindh, Peter; Strömberg, Mattias

    2015-03-01

    There is an increasing need to develop novel bioassay methods for low-cost, rapid, and easy-to-use multiplex detection of pathogens in various fields ranging from human infectious disease diagnosis, drinking water quality control, to food safety applications. Due to their unique advantages, magnetic and optomagnetic bioassay principles are particularly promising for biodetection platforms that will be used in developing countries. In this paper, an optomagnetic method for rapid and cost-efficient qualitative biplex detection of bacterial DNA sequences is demonstrated. Within less than two hours, the assay gives an answer to whether none, both, or only one of the bacterial DNA sequences is present in the sample. The assay relies on hybridization of oligonucleotide-functionalized magnetic nanobeads of two different sizes to rolling circle amplification (RCA) products originating from two different bacterial targets. The different bead sizes are equipped with different oligonucleotide probes, complementary to only one of the RCA products, and the read-out is carried out in the same sample volume. In an optomagnetic setup, the frequency modulation of transmitted laser light in response to an applied AC magnetic field is measured. The presented methodology is potentially interesting for low-cost screening of pathogens relating to both human and veterinary medicine in resource-poor regions of the world.

  8. Heterodyne coherent detection of WDM PDM-QPSK signals with spectral efficiency of 4b/s/Hz.

    PubMed

    Li, Xinying; Dong, Ze; Yu, Jianjun; Yu, Jianguo; Chi, Nan

    2013-04-01

    We experimentally demonstrate heterodyne coherent detection of 8 × 112-Gb/s ultra-density wavelength-division-multiplexing (WDM) polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) signal after 1120-km single-mode fiber-28 (SMF-28) transmission. The spectral efficiency (SE) is 4b/s/Hz. It is the first time to realize WDM signal transmission with high SE by adopting heterodyne coherent detection. At the heterodyne coherent receiver, intermediate frequency (IF) down conversion is realized in digital frequency domain after analog-to-digital conversion. A digital post filter and 1-bit maximum likelihood sequence estimation (MLSE) adopted after carrier phase estimation (CPE) in the conventional digital-signal-processing (DSP) process is used to suppress the enhanced noise and crosstalk as well as overcome the filtering effects. The bit-error ratio (BER) for all channels is under the forward-error-correction (FEC) limit of 3.8 × 10(-3) after 1120-km SMF-28 transmission.

  9. Diagnostic efficiency of abattoir meat inspection service in Ethiopia to detect carcasses infected with Mycobacterium bovis: Implications for public health

    PubMed Central

    2010-01-01

    Background Bovine Tuberculosis (BTB) is a widespread and endemic disease of cattle in Ethiopia posing a significant threat to public health. Regular surveillance by skin test, bacteriology and molecular methods is not feasible due to lack of resource. Thus, routine abattoir (RA) inspection will continue to play a key role for national surveillance. We evaluated efficiency of RA inspection for diagnosis of Mycobacterium bovis infection and discussed its public health implications in light of a high risk of human exposure. Methods The study was conducted in five abattoirs: Addis Ababa, Adama, Hawassa, Yabello and Melge-Wondo abattoirs. The efficiency of routine abattoir (RA) inspection was validated in comparison to detailed abattoir (DA) inspection, followed by culture and microscopy (CM) and region of difference (RD) deletion analysis. Diagnostic accuracies (with corresponding measures of statistical uncertainty) were determined by computing test property statistics (sensitivity and specificity) and likelihood estimations using web-based SISA diagnostic statistics software. Post-test probability of detecting TB infected carcasses was estimated using nomograms. Agreement between RA and DA inspections was measured using kappa statistics. The study was conducted and reported in accordance with standards for reporting of diagnostic accuracy (STARD) requirements. Both routine and detailed meat inspection protocols were performed on a subpopulation of 3322 cattle selected randomly from among 78,269 cattle slaughtered during the study period. Three hundred thirty seven carcasses identified through detailed meat inspection protocols were subjected to culture and microscopy; of the 337, a subset of 105 specimens for culture and microscopy were subjected to further molecular testing. Results There was a substantial agreement between RA and DA inspections in Addis Ababa (Kappa = 0.7) and Melge-Wondo abattoirs (Kappa = 0.67). In Adama, Hawassa and Yabello abattoirs, the

  10. Nanostructured zirconia decorated reduced graphene oxide based efficient biosensing platform for non-invasive oral cancer detection.

    PubMed

    Kumar, Suveen; Sharma, Jai Gopal; Maji, Sagar; Malhotra, Bansi Dhar

    2016-04-15

    We report results of the studies relating to fabrication of a non-invasive, label-free and an efficient biosensing platform for detection of the oral cancer biomarker (CYFRA-21-1). One step hydrothermal process was used for uniform decoration of nanostructured zirconia (average particle size 13 nm) on reduced graphene oxide (ZrO2-RGO) to avoid coagulation of the zirconia nanoparticles and to obtain enhanced electrochemical performance of ZrO2-RGO nanocomposite based biosensor. Further, ZrO2-RGO has been functionalized using 3-aminopropyl triethoxy saline (APTES) and electrophoretically deposited on the indium tin oxide coated glass substrate at a low DC potential.The APTES/ZrO2-RGO/ITO electrode exhibits improved heterogeneous electron transfer (more than two times) with respect to that of the APTES/ZrO2/ITO electrode indicating faster electron transfer kinetics. The -NH2 containing APTES/ZrO2-RGO/ITO platform is further biofunctionalized with anti-CYFRA-21-1. The structural and morphological investigations of the ZrO2-RGO based biosensing platform have been accomplished using X-ray diffraction (XRD), electrochemical, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) studies. This immunosensor exhibits a wider linear detection range (2-22 ng mL(-1)), excellent sensitivity (0.756 µA mL ng(-1)) and a remarkable lower detection limit of 0.122 ng mL(-1). The observed results have been validated via enzyme linked immunosorbent assay (ELISA).

  11. Effective channel estimation and efficient symbol detection for multi-input multi-output underwater acoustic communications

    NASA Astrophysics Data System (ADS)

    Ling, Jun

    Achieving reliable underwater acoustic communications (UAC) has long been recognized as a challenging problem owing to the scarce bandwidth available and the reverberant spread in both time and frequency domains. To pursue high data rates, we consider a multi-input multi-output (MIMO) UAC system, and our focus is placed on two main issues regarding a MIMO UAC system: (1) channel estimation, which involves the design of the training sequences and the development of a reliable channel estimation algorithm, and (2) symbol detection, which requires interference cancelation schemes due to simultaneous transmission from multiple transducers. To enhance channel estimation performance, we present a cyclic approach for designing training sequences with good auto- and cross-correlation properties, and a channel estimation algorithm called the iterative adaptive approach (IAA). Sparse channel estimates can be obtained by combining IAA with the Bayesian information criterion (BIC). Moreover, we present sparse learning via iterative minimization (SLIM) and demonstrate that SLIM gives similar performance to IAA but at a much lower computational cost. Furthermore, an extension of the SLIM algorithm is introduced to estimate the sparse and frequency modulated acoustic channels. The extended algorithm is referred to as generalization of SLIM (GoSLIM). Regarding symbol detection, a linear minimum mean-squared error based detection scheme, called RELAX-BLAST, which is a combination of vertical Bell Labs layered space-time (V-BLAST) algorithm and the cyclic principle of the RELAX algorithm, is presented and it is shown that RELAX-BLAST outperforms V-BLAST. We show that RELAX-BLAST can be implemented efficiently by making use of the conjugate gradient method and diagonalization properties of circulant matrices. This fast implementation approach requires only simple fast Fourier transform operations and facilitates parallel implementations. The effectiveness of the proposed MIMO schemes

  12. Nanostructured zirconia decorated reduced graphene oxide based efficient biosensing platform for non-invasive oral cancer detection.

    PubMed

    Kumar, Suveen; Sharma, Jai Gopal; Maji, Sagar; Malhotra, Bansi Dhar

    2016-04-15

    We report results of the studies relating to fabrication of a non-invasive, label-free and an efficient biosensing platform for detection of the oral cancer biomarker (CYFRA-21-1). One step hydrothermal process was used for uniform decoration of nanostructured zirconia (average particle size 13 nm) on reduced graphene oxide (ZrO2-RGO) to avoid coagulation of the zirconia nanoparticles and to obtain enhanced electrochemical performance of ZrO2-RGO nanocomposite based biosensor. Further, ZrO2-RGO has been functionalized using 3-aminopropyl triethoxy saline (APTES) and electrophoretically deposited on the indium tin oxide coated glass substrate at a low DC potential.The APTES/ZrO2-RGO/ITO electrode exhibits improved heterogeneous electron transfer (more than two times) with respect to that of the APTES/ZrO2/ITO electrode indicating faster electron transfer kinetics. The -NH2 containing APTES/ZrO2-RGO/ITO platform is further biofunctionalized with anti-CYFRA-21-1. The structural and morphological investigations of the ZrO2-RGO based biosensing platform have been accomplished using X-ray diffraction (XRD), electrochemical, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) studies. This immunosensor exhibits a wider linear detection range (2-22 ng mL(-1)), excellent sensitivity (0.756 µA mL ng(-1)) and a remarkable lower detection limit of 0.122 ng mL(-1). The observed results have been validated via enzyme linked immunosorbent assay (ELISA). PMID:26657594

  13. Effects of the time interval between fusion and activation on in vitro rabbit nuclear transfer efficiency when nuclear donor cells are derived from older adults.

    PubMed

    Cervera, R P; Garcia-Ximénez, F

    2004-05-01

    Cloning older adult rabbits can serve as a model in animal breeding, biodiversity preservation and in human therapeutic cloning. To establish the required exposure time of fibroblasts from these kind of animals to reprogramming factors, in the present study three different time intervals between fusion and activation were tested (30 min, 30-ADF group; 60 min, 60-ADF group; and 90 min, 90-ADF group). Vitrified epithelial fibroblasts derived from four older adult rabbit females (D1, D2, D3 and D4) and cultured from passages 0 to 4 were used as nuclear donors. Nuclear status of reconstructed embryos was not evaluated. No differences were observed in blastocyst rate (30-ADF 21% vs 60-ADF 19% vs 90-ADF 18%). Differences in hatching rates did not reach significance (30-ADF 11% vs 60-ADF 18% vs 90-ADF 18%). However, in the 60- and 90-ADF groups, embryos reached the blastocyst stage earlier than in the 30-ADF group (day 4: 40% and 50% vs 8%; p > 0.05). Moreover, the quality of blastocysts (good vs poor) was lower in the 30-ADF group (good: 30-ADF 38% vs 60-ADF 90% vs 90-ADF 90%; p > 0.05). Overall, these results suggest an unfavourable effect of the shortest exposure time tested (30 min). Differences between specimen origins were detected (blastocyst and hatching rates: D2 (26%; 25%) and D4 (25%; 27%) vs D1 (10%; 11%) and D3 (12%; 12%)), but significance were not reached. Effect of culture passage was not detected in any parameter studied. PMID:15460108

  14. Identification of a Neurologic Scale that Optimizes EMS Detection of Older Adult Traumatic Brain Injury Patients who Require Transport to a Trauma Center

    PubMed Central

    Wasserman, Erin B; Shah, Manish N; Jones, Courtney MC; Cushman, Jeremy T; Caterino, Jeffrey M; Bazarian, Jeffrey J; Gillespie, Suzanne M; Cheng, Julius D; Dozier, Ann

    2016-01-01

    Objective We sought to identify a scale or components of a scale that optimize detection of older adult TBI patients who require transport to a trauma center, regardless of mechanism. Methods We assembled a consensus panel consisting of nine experts in geriatric emergency medicine, prehospital medicine, trauma surgery, geriatric medicine, and TBI, as well as prehospital providers, to evaluate the existing scales used to identify TBI. We reviewed the relevant literature and solicited group feedback to create a list of candidate scales and criteria for evaluation. Using the nominal group technique, scales were evaluated by the expert panel through an iterative process until consensus was achieved. Results We identified 15 scales for evaluation. The panel’s criteria for rating the scales included: ease of administration, prehospital familiarity with scale components, feasibility of use with older adults, time to administer, and strength of evidence for their performance in the prehospital setting. After review and discussion of aggregated ratings, the panel identified the Simplified Motor Scale, GCS–Motor Component, and AVPU (alert, voice, pain, unresponsive) as the strongest scales but determined that none meet all EMS provider and patient needs due to poor usability and lack of supportive evidence. The panel proposed that a dichotomized decision scheme that includes domains of the top-rated scales — level of alertness (alert vs. not alert) and motor function (obeys commands vs. does not obey) — may be more effective in identifying older adult TBI patients who require transport to a trauma center in the prehospital setting. Conclusions Existing scales to identify TBI are inadequate to detect older adult TBI patients who require transport to a trauma center. A new algorithm, derived from elements of previously established scales, has potential to guide prehospital providers in improving the triage of older adult TBI patients, but needs further evaluation prior

  15. Efficient In Planta Detection and Dissection of De Novo Mutation Events in the Arabidopsis thaliana Disease Resistance Gene UNI.

    PubMed

    Ogawa, Tomohiko; Mori, Akiko; Igari, Kadunari; Morita, Miyo Terao; Tasaka, Masao; Uchida, Naoyuki

    2016-06-01

    Plants possess disease resistance (R) proteins encoded by R genes, and each R protein recognizes a specific pathogen factor(s) for immunity. Interestingly, a remarkably high degree of polymorphisms in R genes, which are traces of past mutation events during evolution, suggest the rapid diversification of R genes. However, little is known about molecular aspects that facilitate the rapid change of R genes because of the lack of tools that enable us to monitor de novo R gene mutations efficiently in an experimentally feasible time scale, especially in living plants. Here we introduce a model assay system that enables efficient in planta detection of de novo mutation events in the Arabidopsis thaliana R gene UNI in one generation. The uni-1D mutant harbors a gain-of-function allele of the UNI gene. uni-1D heterozygous individuals originally exhibit dwarfism with abnormally short stems. However, interestingly, morphologically normal stems sometimes emerge spontaneously from the uni-1D plants, and the morphologically reverted tissues carry additional de novo mutations in the UNI gene. Strikingly, under an extreme condition, almost half of the examined population shows the reversion phenomenon. By taking advantage of this phenomenon, we demonstrate that the reversion frequency is remarkably sensitive to a variety of fluctuations in DNA stability, underlying a mutable tendency of the UNI gene. We also reveal that activities of the salicylic acid pathway and DNA damage sensor pathway are involved in the reversion phenomenon. Thus, we provide an experimentally feasible model tool to explore factors and conditions that significantly affect the R gene mutation phenomenon. PMID:27016096

  16. Distributed Denial of Service Attack Source Detection Using Efficient Traceback Technique (ETT) in Cloud-Assisted Healthcare Environment.

    PubMed

    Latif, Rabia; Abbas, Haider; Latif, Seemab; Masood, Ashraf

    2016-07-01

    Security and privacy are the first and foremost concerns that should be given special attention when dealing with Wireless Body Area Networks (WBANs). As WBAN sensors operate in an unattended environment and carry critical patient health information, Distributed Denial of Service (DDoS) attack is one of the major attacks in WBAN environment that not only exhausts the available resources but also influence the reliability of information being transmitted. This research work is an extension of our previous work in which a machine learning based attack detection algorithm is proposed to detect DDoS attack in WBAN environment. However, in order to avoid complexity, no consideration was given to the traceback mechanism. During traceback, the challenge lies in reconstructing the attack path leading to identify the attack source. Among existing traceback techniques, Probabilistic Packet Marking (PPM) approach is the most commonly used technique in conventional IP- based networks. However, since marking probability assignment has significant effect on both the convergence time and performance of a scheme, it is not directly applicable in WBAN environment due to high convergence time and overhead on intermediate nodes. Therefore, in this paper we have proposed a new scheme called Efficient Traceback Technique (ETT) based on Dynamic Probability Packet Marking (DPPM) approach and uses MAC header in place of IP header. Instead of using fixed marking probability, the proposed scheme uses variable marking probability based on the number of hops travelled by a packet to reach the target node. Finally, path reconstruction algorithms are proposed to traceback an attacker. Evaluation and simulation results indicate that the proposed solution outperforms fixed PPM in terms of convergence time and computational overhead on nodes. PMID:27189623

  17. Gamma-ray detection efficiency of the microchannel plate installed as an ion detector in the low energy particle instrument onboard the GEOTAIL satellite

    SciTech Connect

    Tanaka, Y. T.; Yoshikawa, I.; Yoshioka, K.; Terasawa, T.; Saito, Y.; Mukai, T.

    2007-03-15

    A microchannel plate (MCP) assembly has been used as an ion detector in the low energy particle (LEP) instrument onboard the magnetospheric satellite GEOTAIL. Recently the MCP assembly has detected gamma rays emitted from an astronomical object and has been shown to provide unique information of gamma rays if they are intense enough. However, the detection efficiency for gamma rays was not measured before launch, and therefore we could not analyze the LEP data quantitatively. In this article, we report the gamma-ray detection efficiency of the MCP assembly. The measured efficiencies are 1.29%{+-}0.71% and 0.21%{+-}0.14% for normal incidence 60 and 662 keV gamma rays, respectively. The incident angle dependence is also presented. Our calibration is crucial to study high energy astrophysical phenomena by using the LEP.

  18. Gamma-ray detection efficiency of the microchannel plate installed as an ion detector in the low energy particle instrument onboard the GEOTAIL satellite.

    PubMed

    Tanaka, Y T; Yoshikawa, I; Yoshioka, K; Terasawa, T; Saito, Y; Mukai, T

    2007-03-01

    A microchannel plate (MCP) assembly has been used as an ion detector in the low energy particle (LEP) instrument onboard the magnetospheric satellite GEOTAIL. Recently the MCP assembly has detected gamma rays emitted from an astronomical object and has been shown to provide unique information of gamma rays if they are intense enough. However, the detection efficiency for gamma rays was not measured before launch, and therefore we could not analyze the LEP data quantitatively. In this article, we report the gamma-ray detection efficiency of the MCP assembly. The measured efficiencies are 1.29%+/-0.71% and 0.21%+/-0.14% for normal incidence 60 and 662 keV gamma rays, respectively. The incident angle dependence is also presented. Our calibration is crucial to study high energy astrophysical phenomena by using the LEP.

  19. Genotypic detection and evaluation of the removal efficiency of Giardia duodenalis at municipal wastewater treatment plants in Northern South Africa.

    PubMed

    Samie, A; Ntekele, P

    2014-03-01

    Over the past decade, Giardia duodenalis has increasingly been implicated in diarrheal outbreaks and water and wastewater have been recognized as important vehicles for diseases. Although studies have reported the occurrence of these parasites in developed countries, their occurrence in water and wastewater bodies in these countries including South Africa has not been thoroughly investigated. In the present study, wastewater samples from 6 different sewage treatment plants in the Vhembe District were collected for a period of 12 months. The samples were concentrated and tested for the presence of G. duodenalis using both microscopy and polymerase chain reaction methods targeting the tpi gene. Of the 79 wastewater samples tested, 25 (31.65%) were positive. Of these, 15 (60%) were assemblage A, while 8 (32%) were assemblage B and 2 samples (8%) were positive for both genogroups. Assemblage A was more common in February 2010 while assemblage B showed two peaks in December-January and March-April and was not detected in May 2010. The general removal rate was 40% for plants using biological filters and 20% for plants using activated sludge. The present study has shown that Giardia assemblage A is more common in sewage treatment plants in the Vhembe District, but the removal efficiency was low. This represents a public health hazard since these organisms might contaminate drinking water sources. Therefore action needs to be taken for the design of more effective procedures or methods for the removal of these parasites from the environment in order to avoid potential outbreaks.

  20. Wrapping cytochrome c around single-wall carbon nanotube: engineered nanohybrid building blocks for infrared detection at high quantum efficiency

    NASA Astrophysics Data System (ADS)

    Gong, Youpin; Liu, Qingfeng; Wilt, Jamie Samantha; Gong, Maogang; Ren, Shenqiang; Wu, Judy

    2015-06-01

    Biomolecule cytochrome c (Cty c), a small molecule of a chain of amino acids with extraordinary electron transport, was helically wrapped around a semiconductive single-wall carbon nanotube (s-SWCNT) to form a molecular building block for uncooled infrared detection with two uniquely designed functionalities: exciton dissociation to free charge carriers at the heterojunction formed on the s-SWCNT/Cty c interface and charge transport along the electron conducting chain of Cty c (acceptor) and hole conducting channel through s-SWCNT (donor). Such a design aims at addressing the long-standing challenges in exciton dissociation and charge transport in an SWCNT network, which have bottlenecked development of photonic SWCNT-based infrared detectors. Using these building blocks, uncooled s-SWCNT/Cyt c thin film infrared detectors were synthesized and shown to have extraordinary photoresponsivity up to 0.77 A W-1 due to a high external quantum efficiency (EQE) in exceeding 90%, which represents a more than two orders of magnitude enhancement than the best previously reported on CNT-based infrared detectors with EQE of only 1.72%. From a broad perspective, this work on novel s-SWCNT/Cyt c nanohybrid infrared detectors has developed a successful platform of engineered carbon nanotube/biomolecule building blocks with superior properties for optoelectronic applications.

  1. Efficiency of using correlation function for estimation of probability of substance detection on the base of THz spectral dynamics

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Peskov, Nikolay V.; Kirillov, Dmitry A.

    2012-10-01

    One of the problems arising in Time-Domain THz spectroscopy for the problem of security is the developing the criteria for assessment of probability for the detection and identification of the explosive and drugs. We analyze the efficiency of using the correlation function and another functional (more exactly, spectral norm) for this aim. These criteria are applied to spectral lines dynamics. For increasing the reliability of the assessment we subtract the averaged value of THz signal during time of analysis of the signal: it means deleting the constant from this part of the signal. Because of this, we can increase the contrast of assessment. We compare application of the Fourier-Gabor transform with unbounded (for example, Gaussian) window, which slides along the signal, for finding the spectral lines dynamics with application of the Fourier transform in short time interval (FTST), in which the Fourier transform is applied to parts of the signals, for the same aim. These methods are close each to other. Nevertheless, they differ by series of frequencies which they use. It is important for practice that the optimal window shape depends on chosen method for obtaining the spectral dynamics. The probability enhancements if we can find the train of pulses with different frequencies, which follow sequentially. We show that there is possibility to get pure spectral lines dynamics even under the condition of distorted spectrum of the substance response on the action of the THz pulse.

  2. Wrapping cytochrome c around single-wall carbon nanotube: engineered nanohybrid building blocks for infrared detection at high quantum efficiency.

    PubMed

    Gong, Youpin; Liu, Qingfeng; Wilt, Jamie Samantha; Gong, Maogang; Ren, Shenqiang; Wu, Judy

    2015-06-11

    Biomolecule cytochrome c (Cty c), a small molecule of a chain of amino acids with extraordinary electron transport, was helically wrapped around a semiconductive single-wall carbon nanotube (s-SWCNT) to form a molecular building block for uncooled infrared detection with two uniquely designed functionalities: exciton dissociation to free charge carriers at the heterojunction formed on the s-SWCNT/Cty c interface and charge transport along the electron conducting chain of Cty c (acceptor) and hole conducting channel through s-SWCNT (donor). Such a design aims at addressing the long-standing challenges in exciton dissociation and charge transport in an SWCNT network, which have bottlenecked development of photonic SWCNT-based infrared detectors. Using these building blocks, uncooled s-SWCNT/Cyt c thin film infrared detectors were synthesized and shown to have extraordinary photoresponsivity up to 0.77 A W(-1) due to a high external quantum efficiency (EQE) in exceeding 90%, which represents a more than two orders of magnitude enhancement than the best previously reported on CNT-based infrared detectors with EQE of only 1.72%. From a broad perspective, this work on novel s-SWCNT/Cyt c nanohybrid infrared detectors has developed a successful platform of engineered carbon nanotube/biomolecule building blocks with superior properties for optoelectronic applications.

  3. Efficient Genome-Wide Detection and Cataloging of EMS-Induced Mutations Using Exome Capture and Next-Generation Sequencing.

    PubMed

    Henry, Isabelle M; Nagalakshmi, Ugrappa; Lieberman, Meric C; Ngo, Kathie J; Krasileva, Ksenia V; Vasquez-Gross, Hans; Akhunova, Alina; Akhunov, Eduard; Dubcovsky, Jorge; Tai, Thomas H; Comai, Luca

    2014-04-11

    Chemical mutagenesis efficiently generates phenotypic variation in otherwise homogeneous genetic backgrounds, enabling functional analysis of genes. Advances in mutation detection have brought the utility of induced mutant populations on par with those produced by insertional mutagenesis, but systematic cataloguing of mutations would further increase their utility. We examined the suitability of multiplexed global exome capture and sequencing coupled with custom-developed bioinformatics tools to identify mutations in well-characterized mutant populations of rice (Oryza sativa) and wheat (Triticum aestivum). In rice, we identified ∼18,000 induced mutations from 72 independent M2 individuals. Functional evaluation indicated the recovery of potentially deleterious mutations for >2600 genes. We further observed that specific sequence and cytosine methylation patterns surrounding the targeted guanine residues strongly affect their probability to be alkylated by ethyl methanesulfonate. Application of these methods to six independent M2 lines of tetraploid wheat demonstrated that our bioinformatics pipeline is applicable to polyploids. In conclusion, we provide a method for developing large-scale induced mutation resources with relatively small investments that is applicable to resource-poor organisms. Furthermore, our results demonstrate that large libraries of sequenced mutations can be readily generated, providing enhanced opportunities to study gene function and assess the effect of sequence and chromatin context on mutations. PMID:24728647

  4. A NIR spectroscopy-based efficient approach to detect fraudulent additions within mixtures of dried porcini mushrooms.

    PubMed

    Casale, Monica; Bagnasco, Lucia; Zotti, Mirca; Di Piazza, Simone; Sitta, Nicola; Oliveri, Paolo

    2016-11-01

    Boletus edulis and allied species (BEAS), known as "porcini mushrooms", represent almost the totality of wild mushrooms placed on the Italian market, both fresh and dehydrated. Furthermore, considerable amounts of these dried fungi are imported from China. The presence of Tylopilus spp. and other extraneous species (i.e., species edible but not belonging to BEAS) within dried porcini mushrooms - mainly from those imported from China and sold in Italy - may represent an evaluable problem from a commercial point of view. The purpose of the present study is to evaluate near-infrared spectroscopy (NIRS) as a rapid and effective alternative to classical methods for identifying extraneous species within dried porcini batches and detecting related commercial frauds. To this goal, 80 dried fungi including BEAS, Tylopilus spp., and Boletus violaceofuscus were analysed by NIRS. For each sample, 3 different parts of the pileus (pileipellis, flesh and hymenium) were analysed and a low-level strategy for data fusion, consisting of combining the signals obtained by the different parts before data processing, was applied. Then, NIR spectra were used to develop reliable and efficient class-models using a novel method, partial least squares density modelling (PLS-DM), and the two most commonly used class-modelling techniques, UNEQ and SIMCA. The results showed that NIR spectroscopy coupled with chemometric class-modelling technique can be suggested as an effective analytical strategy to check the authenticity of dried BEAS mushrooms.

  5. Soft X-ray and extreme utraviolet quantum detection efficiency of potassium chloride photocathode layers on microchannel plates

    NASA Technical Reports Server (NTRS)

    Siegmund, Oswald H. W.; Everman, Elaine; Hull, Jeff; Vallerga, John V.; Lampton, Michael

    1988-01-01

    The quantum detection efficiency (QDE) of KCl photocathodes in the 44-1460 A range was investigated. An opaque layer of KCl, about 15,000-A-thick, was evaporated and applied the surface of a microchannel plate (MCP), and the contribution of the photocathode material in the channels (and on the interchannel web) to the QDE was measured using a Z stack MCP detector. It is shown that KCl is a relatively stable photocathode material, with the QDE equal to 30-40 percent in the EUV. At wavelengths above 200 A, the QDE is slightly better than the QDE of CsI, as reported by Siegmund et al. (1986). While the shape of the QDE curve as a function of wavelength is similar to those reported for CsI and KBr, KCl was found to lack the high QDE peak found in the curves of CsI and KBr at about 100 A. A simple QDE model is described, the predictions of which were found to agree with the measurements on the KCl photocathode.

  6. A NIR spectroscopy-based efficient approach to detect fraudulent additions within mixtures of dried porcini mushrooms.

    PubMed

    Casale, Monica; Bagnasco, Lucia; Zotti, Mirca; Di Piazza, Simone; Sitta, Nicola; Oliveri, Paolo

    2016-11-01

    Boletus edulis and allied species (BEAS), known as "porcini mushrooms", represent almost the totality of wild mushrooms placed on the Italian market, both fresh and dehydrated. Furthermore, considerable amounts of these dried fungi are imported from China. The presence of Tylopilus spp. and other extraneous species (i.e., species edible but not belonging to BEAS) within dried porcini mushrooms - mainly from those imported from China and sold in Italy - may represent an evaluable problem from a commercial point of view. The purpose of the present study is to evaluate near-infrared spectroscopy (NIRS) as a rapid and effective alternative to classical methods for identifying extraneous species within dried porcini batches and detecting related commercial frauds. To this goal, 80 dried fungi including BEAS, Tylopilus spp., and Boletus violaceofuscus were analysed by NIRS. For each sample, 3 different parts of the pileus (pileipellis, flesh and hymenium) were analysed and a low-level strategy for data fusion, consisting of combining the signals obtained by the different parts before data processing, was applied. Then, NIR spectra were used to develop reliable and efficient class-models using a novel method, partial least squares density modelling (PLS-DM), and the two most commonly used class-modelling techniques, UNEQ and SIMCA. The results showed that NIR spectroscopy coupled with chemometric class-modelling technique can be suggested as an effective analytical strategy to check the authenticity of dried BEAS mushrooms. PMID:27591669

  7. Calculation of the absolute detection efficiency of a moderated /sup 235/U neutron detector on the Tokamak Fusion Test Reactor

    SciTech Connect

    Ku, L.P.; Hendel, H.W.; Liew, S.L.

    1989-02-01

    Neutron transport simulations have been carried out to calculate the absolute detection efficiency of a moderated /sup 235/U neutron detector which is used on the TFTR as a part of the primary fission detector diagnostic system for measuring fusion power yields. Transport simulations provide a means by which the effects of variations in various shielding and geometrical parameters can be explored. These effects are difficult to study in calibration experiments. The calculational model, benchmarked against measurements, can be used to complement future detector calibrations, when the high level of radioactivity resulting from machine operation may severely restrict access to the tokamak. We present a coupled forward-adjoint algorithm, employing both the deterministic and Monte Carlo sampling methods, to model the neutron transport in the complex tokamak and detector geometries. Sensitivities of the detector response to the major and minor radii, and angular anisotropy of the neutron emission are discussed. A semi-empirical model based on matching the calculational results with a small set of experiments produces good agreement (+-15%) for a wide range of source energies and geometries. 20 refs., 6 figs., 4 tabs.

  8. The detective quantum efficiency of photon-counting x-ray detectors using cascaded-systems analyses

    SciTech Connect

    Tanguay, Jesse; Yun, Seungman; Kim, Ho Kyung; Cunningham, Ian A.

    2013-04-15

    Purpose: Single-photon counting (SPC) x-ray imaging has the potential to improve image quality and enable new advanced energy-dependent methods. The purpose of this study is to extend cascaded-systems analyses (CSA) to the description of image quality and the detective quantum efficiency (DQE) of SPC systems. Methods: Point-process theory is used to develop a method of propagating the mean signal and Wiener noise-power spectrum through a thresholding stage (required to identify x-ray interaction events). The new transfer relationships are used to describe the zero-frequency DQE of a hypothetical SPC detector including the effects of stochastic conversion of incident photons to secondary quanta, secondary quantum sinks, additive noise, and threshold level. Theoretical results are compared with Monte Carlo calculations assuming the same detector model. Results: Under certain conditions, the CSA approach can be applied to SPC systems with the additional requirement of propagating the probability density function describing the total number of image-forming quanta through each stage of a cascaded model. Theoretical results including DQE show excellent agreement with Monte Carlo calculations under all conditions considered. Conclusions: Application of the CSA method shows that false counts due to additive electronic noise results in both a nonlinear image signal and increased image noise. There is a window of allowable threshold values to achieve a high DQE that depends on conversion gain, secondary quantum sinks, and additive noise.

  9. Wrapping cytochrome c around single-wall carbon nanotube: engineered nanohybrid building blocks for infrared detection at high quantum efficiency

    PubMed Central

    Gong, Youpin; Liu, Qingfeng; Wilt, Jamie Samantha; Gong, Maogang; Ren, Shenqiang; Wu, Judy

    2015-01-01

    Biomolecule cytochrome c (Cty c), a small molecule of a chain of amino acids with extraordinary electron transport, was helically wrapped around a semiconductive single-wall carbon nanotube (s-SWCNT) to form a molecular building block for uncooled infrared detection with two uniquely designed functionalities: exciton dissociation to free charge carriers at the heterojunction formed on the s-SWCNT/Cty c interface and charge transport along the electron conducting chain of Cty c (acceptor) and hole conducting channel through s-SWCNT (donor). Such a design aims at addressing the long-standing challenges in exciton dissociation and charge transport in an SWCNT network, which have bottlenecked development of photonic SWCNT-based infrared detectors. Using these building blocks, uncooled s-SWCNT/Cyt c thin film infrared detectors were synthesized and shown to have extraordinary photoresponsivity up to 0.77 A W−1 due to a high external quantum efficiency (EQE) in exceeding 90%, which represents a more than two orders of magnitude enhancement than the best previously reported on CNT-based infrared detectors with EQE of only 1.72%. From a broad perspective, this work on novel s-SWCNT/Cyt c nanohybrid infrared detectors has developed a successful platform of engineered carbon nanotube/biomolecule building blocks with superior properties for optoelectronic applications. PMID:26066737

  10. Disability and chronic disease among older adults in India: detecting vulnerable populations through the WHO SAGE Study.

    PubMed

    Basu, Sanjay; King, Abby C

    2013-12-01

    Chronic noncommunicable diseases (NCDs) are now prevalent in many low- and middle-income countries and confer a heightened risk of disability. It is unclear how public health programs can identify the older adults at highest risk of disability related to NCDs within diverse developing country populations. We studied nationally representative survey data from 7,150 Indian adults older than 50 years of age who participated in the World Health Organization Study on Global Aging and Adult Health (2007-2010) to identify population subgroups who are highly disabled. Using machine-learning algorithms, we identified sociodemographic correlates of disability. Although having 2 or more symptomatic NCDs was a key correlate of disability, the prevalence of symptomatic, undiagnosed NCDs was highest among the lowest 2 wealth quintiles of Indian adults, contrary to prior hypotheses of increased NCDs with wealth. Women and persons from rural populations were also disproportionately affected by nondiagnosed NCDs, with high out-of-pocket health care expenditures increasing the probability of remaining symptomatic from NCDs. These findings also indicate that NCD prevalence surveillance studies in low- and middle-income countries should expand beyond self-reported diagnoses to include more extensive symptom- and examination-based surveys, given the likely high rate of surveillance bias due to barriers to diagnosis among vulnerable populations.

  11. Detection of Mycobacterium tuberculosis (MTB) in Fecal Specimens From Adults Diagnosed With Pulmonary Tuberculosis Using the Xpert MTB/Rifampicin Test

    PubMed Central

    Kokuto, Hiroyuki; Sasaki, Yuka; Yoshimatsu, Shoji; Mizuno, Kazue; Yi, Lina; Mitarai, Satoshi

    2015-01-01

    Background. The Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) is a fully automated diagnostic test that allows for the detection of MTB including its RIF resistance. Although the test is used for the diagnosis of tuberculosis (TB) in sputum samples worldwide, studies using fecal specimens are scarce. We therefore evaluated the efficacy of the Xpert MTB/RIF test for detection of MTB in fecal specimens obtained from adult pulmonary TB patients, confirmed by culture and/or molecular diagnostic methods. Methods. We conducted a retrospective case-control study to provide proof-of-concept regarding the efficacy of the Xpert MTB/RIF test using fecal samples for diagnosing pulmonary TB via detection of MTB in adult patients (≥20 years) at the Fukujuji Hospital in Tokyo, Japan. Results. Fecal specimens were obtained from 56 active pulmonary TB patients (including 48 sputum smear-positive and 8 sputum smear-negative patients), 10 non-TB patients (including 4 Myocobacterium avium complex infections), and 27 healthy individuals who were exposed to active pulmonary TB patients. The sensitivity of the fecal Xpert MTB/RIF was 100% (81.7%–100%) for detection of MTB in specimens from sputum smear-positive (1+ to 3+) patients, 81.0% (58.1%–94.6%) in specimens from sputum smear scanty positive patients, and 50.0% (15.7%–84.3%) in specimens from sputum smear-negative patients. Meanwhile, each of the fecal specimens from the non-TB group was negative for MTB (specificity 100%; 95% confidence interval, 86.2–100). Conclusions. The fecal Xpert MTB/RIF test could detect MTB in a large proportion of smear-positive pulmonary TB patients, without frequent false-positive results at a TB referral hospital in Japan. PMID:26125035

  12. Contribution of ethyl methanesulfonate vapors to the yield of mutations detected in Drosophila melanogaster when the adult feeding technique is used

    SciTech Connect

    Munoz, E.R.

    1987-01-01

    Ethyl methanesulfonate (EMS) is an alkylating agent widely used in mutation research. In experiments with adult Drosophila melanogaster, EMS is either injected or fed to the flies using different feeding methods that essentially consist of placing the flies in bottles or vials with a piece of tissue paper moistened with a sucrose solution containing the desired concentration of EMS. To determine the extent to which vapors contribute to the mutagenic effect detected in Drosophila when the feeding technique is used, 7-day-old wild-type Samarkand males were fed EMS or were exposed only to its vapors.

  13. Post-Thaw Viable CD45+ Cells and Clonogenic Efficiency are Associated with Better Engraftment and Outcomes after Single Cord Blood Transplantation in Adult Patients with Malignant Diseases.

    PubMed

    Castillo, Nerea; García-Cadenas, Irene; Barba, Pere; Martino, Rodrigo; Azqueta, Carmen; Ferrà, Christelle; Canals, Carme; Sierra, Jorge; Valcárcel, David; Querol, Sergio

    2015-12-01

    The quantity of cells is widely accepted as the main factor influencing the outcome after umbilical cord blood transplantation (UCBT) however, the quality of the cord blood units (CBUs) has been less studied. In order to determine the impact of qualitative variables in UCBT outcomes, we conducted a multicenter retrospective study in adult patients with hematological malignancies who underwent single UCBT after a common myeloablative conditioning regimen. One hundred and ten patients from 3 institutions [median age, 35 years (range 18-55)] were included. Quantitative (TNC and total CD34+cells) and qualitative variables [viable CD45+ (vCD45+), vCD34+ and clonogenic efficiency [(CLONE), quotient of post-thaw colony-forming units (CFU)] and pre-freeze CD34+ cells predicted engraftment in univariate analysis however, only 2 qualitative variables remained significant in the multivariate analysis. Infusion of more than 2 × 10(7) post-thaw vCD45+ cells per kilogram was significantly associated with faster neutrophil (P = .01), platelet engraftment (P = .01), higher disease-free (P = .01) and overall survival (0.02). In addition, CLONE ≥ 20% predicted a faster neutrophil (P = .005), platelet engraftment (P = .01) and contributed to decrease the non-relapse mortality (P = .02). Our study suggests that the vCD45+ cells dose and CLONE are powerful surrogate markers of graft quality and can potentially help on CBUs selection if tested with representative reference samples.

  14. Detection of Ehrlichia chaffeensis in adult and nymphal stage lone star ticks (Amblyomma americanum) from Long Island, New York

    USGS Publications Warehouse

    Mixson, T.R.; Ginsberg, H.S.; Campbell, S.R.; Sumner, J.W.; Paddock, C.D.

    2004-01-01

    The lone star tick, Amblyomma americanum (L.), has increased in abundance in several regions of the northeastern United States, including areas of Long Island, NY. Adult and nymphal stage A. americanum collected from several sites on Long Island were evaluated for infection with Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME), by using a nested polymerase chain reaction assay. Fifty-nine (12.5%) of ,17.3 adults and eight of 11.3 pools of five nymphs each (estimated minimum prevalence of infection 1.4%) contained DNA of E. chaffeensis. These data, coupled with the documented expansion of lone star tick populations in the northeastern United States, confirm that E. chaffeensis is endemic to many areas of Long Island and that HME should be considered among the differential diagnoses of the many distinct tick-borne diseases that occur in this region.

  15. Detection of Ehrlichia chaffeensis in adult and nymphal Amblyomma americanum (Acari: Ixodidae) ticks from Long Island, New York.

    PubMed

    Mixson, Tonya R; Ginsberg, Howard S; Campbell, Scott R; Sumner, John W; Paddock, Christopher D

    2004-11-01

    The lone star tick, Amblyomma americanum (L.), has increased in abundance in several regions of the northeastern United States, including areas of Long Island, NY. Adult and nymphal stage A. americanum collected from several sites on Long Island were evaluated for infection with Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME), by using a nested polymerase chain reaction assay. Fifty-nine (12.5%) of 473 adults and eight of 113 pools of five nymphs each (estimated minimum prevalence of infection 1.4%) contained DNA of E. chaffeensis. These data, coupled with the documented expansion of lone star tick populations in the northeastern United States, confirm that E. chaffeensis is endemic to many areas of Long Island and that HME should be considered among the differential diagnoses of the many distinct tick-borne diseases that occur in this region. PMID:15605650

  16. Oscillometric measure of blood pressure detects association between orthostatic hypotension and depression in population based study of older adults

    PubMed Central

    2013-01-01

    Background White matter hyperintensities may contribute to depression by disrupting neural connections among brain regions that regulate mood. Orthostatic hypotension (OH) may be a risk factor for white matter hyperintensities and accumulating evidence, although limited suggests it may play a role in the development of late-life depression. The aim of this study was to examine the relationship between an oscillometric measure of orthostatic hypotension and depression in population based sample of older adults. Methods We analysed data on adults aged 60 and over from the first wave of The Irish Longitudinal Study on Ageing (TILDA). Depression was assessed using the Center for Epidemiologic Studies – Depression (CES–D) scale and OH was assessed by a sit-to-stand orthostatic stress test; two seated blood pressure measurements were followed by a single standing blood pressure measurement. Participants self reported whether they felt dizzy, light-headed or unsteady on standing. Results Participants with symptomatic OH (SOH, n=20) had the highest mean CES-D score (mean 8.6, SE 1.6) when compared to participants with asymptomatic OH (AOH) (mean 5.6, SE .48) and participants with no OH (mean 5.2, SE .14) and this difference was significant for both comparisons (p<0.001). Linear regression analysis adjusted for socio-demographic and clinical characteristics showed that SOH was associated with higher CES-D scores (unstandardised B coefficient = 2.24; 95% CI .301 - 4.79; p =0.05) compared to participants without OH. AOH was not associated with higher CES-D scores (unstandardised B coefficient =.162; 95% CI -.681, 1.00; p= 0.70). Conclusions Symptomatic orthostatic hypotension is associated with depression in older adults and needs to be considered in studies examining the relationship between vascular disease and depression in older adults. PMID:24138959

  17. Development of a portable instrument for automated measurements of the detective quantum efficiency of x-ray detectors

    NASA Astrophysics Data System (ADS)

    Cunningham, I. A.; Lazarev, S.; Sattarivand, M.; Jankovic, N. D.

    2007-03-01

    The scientific community has generally adopted use of the modulation transfer function (MTF) and detective quantum efficiency (DQE) as primary measures of performance of radiographic detectors. However, measurement of these parameters is generally restricted to experts in laboratory environments due to the required x-ray physics knowledge, specialized instrumentation and computational analyses. We have developed a prototype instrument that automates both the physical measurement and subsequent image analysis to determine the MTF, noise power spectrum (NPS) and DQE of radiographic and mammographic systems. The instrument is placed in the x-ray path directly in front of the detector. A series of images are acquired, saved in "raw" DICOM format and then used to determine the MTF (using the slanted-edge method) and NPS. The number of incident quanta is calculated from measurements of the incident exposure including corrections for air temperature and pressure and ionization chamber spectral response. The primary sources of error are backscatter from the detector and scatter generated within the instrument. These have been minimized to achieve an incident exposure measurement within 2% of a calibrated electrometer and chamber in free space. The MTF and DQE of a commercial CsI-based flat-panel detector were measured over a range of incident exposures from 20 uR to 20 mR per image. Results agreed with both our own laboratory measurements and previously published measurements performed elsewhere with a similar detector within 2% for the MTF and 5% for the DQE. A complete DQE analysis of a clinical digital flat-panel detector is completed in 30 minutes and requires no system modifications.

  18. Test-Retest Reliability of Detection Time Data Measured Using a Masseter Electromyogram in Healthy Young Adults: Preliminary Analysis of Data.

    PubMed

    Miyaoka, Satomi; Miyaoka, Yozo

    2016-04-01

    Few studies have assessed test-retest reliability of flavor detection time in semisolid and solid foods. In this study, test-retest reliability was assessed in 16 healthy young adults (22.6 ± 5.5 years old) on the data collected using a masseter electromyography-based system between two experimental sessions approximately 35 days apart. The overall correlation coefficients were calculated across five test foods; the correlation coefficient for the entire sample was statistically significant. Five correlation coefficients were calculated for individual test foods, but only orange-flavored gummy candy was significantly correlated across the two sessions. These results suggested that flavor detection time measured by the electromyography-based system is basically reliable over time, with considerable variation among flavors. PMID:27166330

  19. Acceptability of an intelligent wireless sensor system for the rapid detection of health issues: findings among home-dwelling older adults and their informal caregivers

    PubMed Central

    Cohen, Christine; Kampel, Thomas; Verloo, Henk

    2016-01-01

    Background Aging at home rather than in an institution is now considered the gold standard. Public health figures document an important demographic transition to an increasingly elderly society. At the same time, this is accompanied by the emergence of significant numbers of innovative technologies to help and support home-dwelling older adults in declining health who wish to remain at home. Study aim To explore the acceptability of intelligent wireless sensor system (IWSS) among home-dwelling older adults in rapidly detecting their health issues. Methods Data were sourced from a pilot 3-month randomized clinical trial that involved 34 older patients in the experimental group (EG) using an IWSS to rapidly detect falls and other health issues at home. The effectiveness of the IWSS was assessed by comparing it to participants’ functional and cognitive status, as measured both before and after the trial. The Resident Assessment Instrument for Home Care, Confusion Assessment Method, Cognitive Performance Scale, Geriatric Depression Scale, and Informed Questionnaire on Cognitive Decline in the Elderly were used for the assessments. Acceptability of the IWSS was explored at the end of the study. Results Both older adults and their informal caregivers considered the performance and usefulness of the IWSS intervention to be low to moderate. A majority of the participants were unsatisfied with its ease of use and found multiple obstacles in using and having an intention to use the IWSS. However, their informal caregivers were more satisfied with the program and gave higher scores for usefulness, ease of use, and intention to use IWSS technology. Conclusion The IWSS displayed low-to-moderate acceptability among the older participants and their informal caregivers. We recommend improving and clarifying several components in the IWSS for the development of a design that is user-centered. PMID:27660417

  20. Acceptability of an intelligent wireless sensor system for the rapid detection of health issues: findings among home-dwelling older adults and their informal caregivers

    PubMed Central

    Cohen, Christine; Kampel, Thomas; Verloo, Henk

    2016-01-01

    Background Aging at home rather than in an institution is now considered the gold standard. Public health figures document an important demographic transition to an increasingly elderly society. At the same time, this is accompanied by the emergence of significant numbers of innovative technologies to help and support home-dwelling older adults in declining health who wish to remain at home. Study aim To explore the acceptability of intelligent wireless sensor system (IWSS) among home-dwelling older adults in rapidly detecting their health issues. Methods Data were sourced from a pilot 3-month randomized clinical trial that involved 34 older patients in the experimental group (EG) using an IWSS to rapidly detect falls and other health issues at home. The effectiveness of the IWSS was assessed by comparing it to participants’ functional and cognitive status, as measured both before and after the trial. The Resident Assessment Instrument for Home Care, Confusion Assessment Method, Cognitive Performance Scale, Geriatric Depression Scale, and Informed Questionnaire on Cognitive Decline in the Elderly were used for the assessments. Acceptability of the IWSS was explored at the end of the study. Results Both older adults and their informal caregivers considered the performance and usefulness of the IWSS intervention to be low to moderate. A majority of the participants were unsatisfied with its ease of use and found multiple obstacles in using and having an intention to use the IWSS. However, their informal caregivers were more satisfied with the program and gave higher scores for usefulness, ease of use, and intention to use IWSS technology. Conclusion The IWSS displayed low-to-moderate acceptability among the older participants and their informal caregivers. We recommend improving and clarifying several components in the IWSS for the development of a design that is user-centered.

  1. Monoclonal antibody against recombinant Fasciola gigantica cathepsin L1H could detect juvenile and adult cathepsin Ls of Fasciola gigantica.

    PubMed

    Wongwairot, Sirima; Kueakhai, Pornanan; Changklungmoa, Narin; Jaikua, Wipaphorn; Sansri, Veerawat; Meemon, Krai; Songkoomkrong, Sineenart; Riengrojpitak, Suda; Sobhon, Prasert

    2015-01-01

    Cathepsin Ls (CatLs), the major cysteine protease secreted by Fasciola spp., are important for parasite digestion and tissue invasion. Fasciola gigantica cathepsin L1H (FgCatL1H) is the isotype expressed in the early stages for migration and invasion. In the present study, a monoclonal antibody (MoAb) against recombinant F. gigantica cathepsin L1H (rFgCatL1H) was produced by hybridoma technique using spleen cells from BALB/c mice immunized with recombinant proFgCatL1H (rproFgCatL1H). This MoAb is an immunoglobulin (Ig)G1 with κ light chain isotype. The MoAb reacted specifically with rproFgCatL1H, the native FgCatL1H at a molecular weight (MW) 38 to 48 kDa in the extract of whole body (WB) of metacercariae and newly excysted juvenile (NEJ) and cross-reacted with rFgCatL1 and native FgCatLs at MW 25 to 28 kDa in WB of 2- and 4-week-old juveniles, adult, and adult excretory-secretory (ES) fractions by immunoblotting and indirect ELISA. It did not cross-react with antigens in WB fractions from other parasites, including Gigantocotyle explanatum, Paramphistomum cervi, Gastrothylax crumenifer, Eurytrema pancreaticum, Setaria labiato-papillosa, and Fischoederius cobboldi. By immunolocalization, MoAb against rFgCatL1H reacted with the native protein in the gut of metacercariae and NEJ and also cross-reacted with CatL1 in 2- and 4-week-old juveniles and adult F. gigantica. Therefore, FgCatL1H and its MoAb may be used for immunodiagnosis of both early and late fasciolosis in ruminants and humans.

  2. Monoclonal antibody against recombinant Fasciola gigantica cathepsin L1H could detect juvenile and adult cathepsin Ls of Fasciola gigantica.

    PubMed

    Wongwairot, Sirima; Kueakhai, Pornanan; Changklungmoa, Narin; Jaikua, Wipaphorn; Sansri, Veerawat; Meemon, Krai; Songkoomkrong, Sineenart; Riengrojpitak, Suda; Sobhon, Prasert

    2015-01-01

    Cathepsin Ls (CatLs), the major cysteine protease secreted by Fasciola spp., are important for parasite digestion and tissue invasion. Fasciola gigantica cathepsin L1H (FgCatL1H) is the isotype expressed in the early stages for migration and invasion. In the present study, a monoclonal antibody (MoAb) against recombinant F. gigantica cathepsin L1H (rFgCatL1H) was produced by hybridoma technique using spleen cells from BALB/c mice immunized with recombinant proFgCatL1H (rproFgCatL1H). This MoAb is an immunoglobulin (Ig)G1 with κ light chain isotype. The MoAb reacted specifically with rproFgCatL1H, the native FgCatL1H at a molecular weight (MW) 38 to 48 kDa in the extract of whole body (WB) of metacercariae and newly excysted juvenile (NEJ) and cross-reacted with rFgCatL1 and native FgCatLs at MW 25 to 28 kDa in WB of 2- and 4-week-old juveniles, adult, and adult excretory-secretory (ES) fractions by immunoblotting and indirect ELISA. It did not cross-react with antigens in WB fractions from other parasites, including Gigantocotyle explanatum, Paramphistomum cervi, Gastrothylax crumenifer, Eurytrema pancreaticum, Setaria labiato-papillosa, and Fischoederius cobboldi. By immunolocalization, MoAb against rFgCatL1H reacted with the native protein in the gut of metacercariae and NEJ and also cross-reacted with CatL1 in 2- and 4-week-old juveniles and adult F. gigantica. Therefore, FgCatL1H and its MoAb may be used for immunodiagnosis of both early and late fasciolosis in ruminants and humans. PMID:25324133

  3. Re-detection vs. new acquisition of high-risk human papillomavirus in mid-adult women.

    PubMed

    Fu, Tsung-Chieh Jane; Carter, Joseph J; Hughes, James P; Feng, Qinghua; Hawes, Stephen E; Schwartz, Stephen M; Xi, Long Fu; Lasof, Taylor; Stern, Joshua E; Galloway, Denise A; Koutsky, Laura A; Winer, Rachel L

    2016-11-15

    To understand high-risk (hr) human papillomavirus (HPV) epidemiology in mid-adulthood, we assessed whether associations between incident detection of hrHPV DNA and recent sexual behavior differed according to whether or not there was serologic evidence of prior infection. From 2011 to 2012, we enrolled 409 women aged 30-50 years into a 6-month longitudinal study. We collected health and sexual behavior histories, enrollment sera for HPV antibody testing, and monthly self-collected vaginal swabs for HPV DNA genotyping. Generalized estimating equations logistic regression identified risk factors for type-specific incident hrHPV DNA, stratified by type-specific hrHPV serostatus at enrollment. Population attributable risks of hrHPV due to prior and recent exposure were estimated. When type-specific hrHPV serology was negative, recent sexual risk behavior was positively associated with incident hrHPV DNA (odds ratio in women reporting ≥3 recent sexual risk behaviors [e.g., new or multiple partners] vs. no recent sexual activity = 9.8, 95% CI: 2.4-40.6). No associations with recent sexual behavior were observed with positive type-specific hrHPV serology. Thirty percent of incident hrHPV DNA detection was attributable to prior infection (with positive serology) and 40% was attributable to recent sexual risk behavior (with negative serology). The proportion of incident hrHPV DNA detection attributable to recent sexual risk behavior decreased with increasing age. Among women with serologic evidence of prior infection, re-detection of the same hrHPV type is likely due to reactivation or intermittent detection of persistent infection. Without serologic evidence of prior infection, new detection is likely due to new acquisition or to intermittent detection of persisting infection. PMID:27448488

  4. RNA-Seq detection of differential gene expression in the rumen of beef steers associated with feed efficiency phenotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient utilization of feedstuffs is an economically important trait in beef production. The rumen is important to the digestive process of steers interacting with feed, microbial populations, and volatile fatty acids indicating it may play a critical role in feed efficiency. To gain an unders...

  5. [Frailty in older adults: detection, community-based intervention, and decision-making in the management of chronic illnesses].

    PubMed

    Tello-Rodríguez, Tania; Varela-Pinedo, Luis

    2016-06-01

    Physical fragility is defined as "a medical syndrome with multiple causes and factors that contribute to its development and that is characterized by decreased strength and resistance as well as reduced physiological functioning, which increase an individual's vulnerability to functional dependence or death." Different multi-systemic pathophysiological processes are involved in the pathogenesis of frailty syndrome, one of the most important being the loss of muscle mass associated with aging or sarcopenia. Several studies have demonstrated that physical frailty increases with age. Physical exercise is the best form of intervention for preventing and treating frailty. In older adults with chronic illnesses, identifying frailty is very important for decision-making, individualizing management, and considering their values and care preferences. PMID:27656934

  6. Dyslipidemia Prevalence in Iranian Adult Men: The Impact of Population-Based Screening on the Detection of Undiagnosed Patients

    PubMed Central

    Mohammadbeigi, Abolfazl; Moshiri, Esamil; Mohammadsalehi, Narges; Ansari, Hossein

    2015-01-01

    Purpose Dyslipidemia has been established as one of the most important modifiable risk factors for cardiovascular disease. Due to the higher prevalence of dyslipidemia in males, this study aimed to estimate the prevalence of dyslipidemia in Iranian urban men. Materials and Methods A screening program was conducted in 845 Iranian men 25 years of age and older in 2014. A health interview survey was conducted to evaluate the prevalence of self-reported dyslipidemia and to collect demographic data, as well as serum lipid profile screening by a reference laboratory. Lipoprotein levels was categorized based on the Adult Treatment Panel III criteria and the data were analyzed using the chi-square test and analysis of variance. Results The overall prevalence of dyslipidemia was 51.8%, and the prevalence of various forms of dyslipidemia was as follows: hypercholesterolemia (≥240 mg/dL), 11.4%; hyper-low-density lipoprotein cholesterol (≥160 mg/dL), 9.6%; hypertriglyceridemia (≥200 mg/dL), 25%; and hypo-high-density lipoprotein (HDL) cholesterol (<40 mg/dL), 34.3%. With the exception of hypo-HDL, all forms of dyslipidemia were significantly less common in men over 65 years of age (p<0.05). Conclusions The prevalence of hypo-HDL and hypertriglyceridemia was higher than expected in Iranian adult men, with half of men 25 years of age and older affected by at least one form of dyslipidemia. A large gap in primary and secondary care was observed, because nearly 80% of patients with dyslipidemia were unaware of their status. Urgent preventive programs and lifestyle changes are necessary to reduce the prevalence of cardiovascular risk factors. PMID:26770936

  7. Asynchronous detection of optical code division multiple access signals using a bandwidth-efficient and wavelength-aware receiver.

    PubMed

    Fok, Mable P; Deng, Yanhua; Prucnal, Paul R

    2010-04-01

    We experimentally demonstrate what we believe to be a novel detection scheme for interfacing asynchronous optical code division multiple access (CDMA) signals with an electronic clock and data recovery system that operates only at the baseband bandwidth. This allows using a large optical bandwidth expansion factor in which the optical chip rate is much larger than the bandwidth of the optoelectronic receiver. The received optical CDMA signal is launched into a four-wave-mixing-based wavelength-aware all-optical front end that rejects multiaccess interference, followed by an amplitude-noise suppression stage comprised of a semiconductor optical amplifier. The clean signal is then converted into a non-return-to-zero-like signal by a baseband receiver. Using the proposed detection scheme, asynchronous transmission and detection of optical CDMA signals is implemented. With the novel detection scheme, the classic CDMA near-far problem is mitigated, and error-free detection is easily obtained.

  8. Impact of pneumococcal vaccination in children on serotype distribution in adult community-acquired pneumonia using the serotype-specific multiplex urinary antigen detection assay.

    PubMed

    Pletz, Mathias W; Ewig, Santiago; Rohde, Gernot; Schuette, Hartwig; Rupp, Jan; Welte, Tobias; Suttorp, Norbert; Forstner, Christina

    2016-04-29

    The aim of the study was to compare the distribution of the vaccine-serotypes covered by pneumococcal conjugate vaccines (PCV7 and PCV13) in adult patients with pneumococcal community-acquired pneumonia in Germany between the periods 2002-2006 and 2007-2011 using a novel serotype-specific multiplex urinary antigen detection assay (SSUA). Vaccination of children started with PCV7 in 2007, which was replaced by PCV13 in 2010. Following confirmation of the accuracy of SSUA in long-term stored urine samples from 112 patients with confirmed pneumonia and known pneumococcal serotype, urine samples of 391 CAPNETZ patients with documented pneumococcal pneumonia (i.e. positive BinaxNOW) Streptococcus pneumoniae urine antigen test) but unknown serotype were tested for the 13 vaccine-serotypes using SSUA. The proportion of PCV7-serotypes significantly decreased in adult patients with pneumonia from 30.6% (2002-6) to 13.3% (2007-11, p < 0.001); in bacteremic pneumonia, PCV7-serotypes completely disappeared (3/14 versus 0/19, p = 0.058). Conversely, pneumococcal serotypes included by PCV13 remained stable during study period with a coverage of 61.5% (2002-06) and 59.7% (2007-11) in non-bacteremic pneumonia and 79% (for both periods) in bacteremic pneumonia, mainly due to an increase in pneumococcal serotypes 1, 3 and 7F during the second period. Thus, implementation of PCV7 in children in Germany in 2007 was associated with a significant decrease in vaccine-serotypes covered by PCV7 in adult patients with non-bacteremic pneumococcal pneumonia and with an elimination of PCV7 vaccine-serotypes in bacteremic pneumococcal pneumonia. PCV13 coverage remained high up to 2011, mainly due to an increase in serotypes 1, 3 and 7F.

  9. Vitamin C in infant formula and adult/pediatric nutritional Formula by ultra-performance liquid chromatography with Ultraviolet detection: first action 2012.22.

    PubMed

    Campos-Giménez, Esther; Fontannaz, Patric; Redeuil, Karine; Kilinc, Tamara; Dowell, Dawn

    2013-01-01

    During the AOAC Annual Meeting held in Las Vegas, NV from September 30 to October 3, 2012, the Stakeholder Panel on Infant Formula and Adult Nutritionals convened to review single-laboratory validation data submitted for the method, Vitamin C in Adult/Pediatric Formula by Ultra-Performance Liquid Chromatography with Ultraviolet Detection. This method is a modified version of the method "HPLC-UV Determination of Total Vitamin C in a Wide Range of Fortified Food Products" previously published in Food Chem., 94, 626-631 (2006). The SLV data from the modified method were reviewed and compared to the standard method performance requirements (SMPR 2012.012), and it was concluded that the method meets the requirements. The method was approved as AOAC Official First Action. The method is based on the acidic extraction of ascorbic acid in the presence of Tris[2-carboxyethyl] phosphine (TCEP) as a reducing agent. Separation was achieved on a C18 column with a sodium acetate eluent (pH 5.4) combined with TCEP and decylamine as an ion-pairing agent. Accuracy rates were between 90 and 100%. Repeatability RSD (RSD,) ranged from 1.4 to 2.5%, and intermediate reproducibility RSD (RSDiR) ranged from 1.3 to 7.5%. PMID:24282948

  10. Association of Sand Dust Particles with Pulmonary Function and Respiratory Symptoms in Adult Patients with Asthma in Western Japan Using Light Detection and Ranging: A Panel Study.

    PubMed

    Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Shimizu, Atsushi; Sano, Hiroyuki; Kato, Kazuhiro; Mikami, Masaaki; Ueda, Yasuto; Tatsukawa, Toshiyuki; Ohga, Hideki; Yamasaki, Akira; Igishi, Tadashi; Kitano, Hiroya; Shimizu, Eiji

    2015-10-16

    Light detection and ranging (LIDAR) can estimate daily volumes of sand dust particles from the East Asian desert to Japan. The objective of this study was to investigate the relationship between sand dust particles and pulmonary function, and respiratory symptoms in adult patients with asthma. One hundred thirty-seven patients were included in the study. From March 2013 to May 2013, the patients measured their morning peak expiratory flow (PEF) and kept daily lower respiratory symptom diaries. A linear mixed model was used to estimate the correlation of the median daily levels of sand dust particles, symptoms scores, and PEF. A heavy sand dust day was defined as an hourly concentration of sand dust particles of >0.1 km(-1). By this criterion, there were 8 heavy sand dust days during the study period. Elevated sand dust particles levels were significantly associated with the symptom score (0.04; 95% confidence interval (CI); 0.03, 0.05), and this increase persisted for 5 days. There was no significant association between PEF and heavy dust exposure (0.01 L/min; 95% CI, -0.62, 0.11). The present study found that sand dust particles were significantly associated with worsened lower respiratory tract symptoms in adult patients with asthma, but not with pulmonary function.

  11. Human young children as well as adults demonstrate 'superior' rapid snake detection when typical striking posture is displayed by the snake.

    PubMed

    Masataka, Nobuo; Hayakawa, Sachiko; Kawai, Nobuyuki

    2010-11-30

    Humans as well as some nonhuman primates have an evolved predisposition to associate snakes with fear by detecting their presence as fear-relevant stimuli more rapidly than fear-irrelevant ones. In the present experiment, a total of 74 of 3- to 4-year-old children and adults were asked to find a single target black-and-white photo of a snake among an array of eight black-and-white photos of flowers as distracters. As target stimuli, we prepared two groups of snake photos, one in which a typical striking posture was displayed by a snake and the other in which a resting snake was shown. When reaction time to find the snake photo was compared between these two types of the stimuli, its mean value was found to be significantly smaller for the photos of snakes displaying striking posture than for the photos of resting snakes in both the adults and children. These findings suggest the possibility that the human perceptual bias for snakes per se could be differentiated according to the difference of the degree to which their presence acts as a fear-relevant stimulus.

  12. Human young children as well as adults demonstrate 'superior' rapid snake detection when typical striking posture is displayed by the snake.

    PubMed

    Masataka, Nobuo; Hayakawa, Sachiko; Kawai, Nobuyuki

    2010-01-01

    Humans as well as some nonhuman primates have an evolved predisposition to associate snakes with fear by detecting their presence as fear-relevant stimuli more rapidly than fear-irrelevant ones. In the present experiment, a total of 74 of 3- to 4-year-old children and adults were asked to find a single target black-and-white photo of a snake among an array of eight black-and-white photos of flowers as distracters. As target stimuli, we prepared two groups of snake photos, one in which a typical striking posture was displayed by a snake and the other in which a resting snake was shown. When reaction time to find the snake photo was compared between these two types of the stimuli, its mean value was found to be significantly smaller for the photos of snakes displaying striking posture than for the photos of resting snakes in both the adults and children. These findings suggest the possibility that the human perceptual bias for snakes per se could be differentiated according to the difference of the degree to which their presence acts as a fear-relevant stimulus. PMID:21152050

  13. Vitamin C in infant formula and adult/pediatric nutritional Formula by ultra-performance liquid chromatography with Ultraviolet detection: first action 2012.22.

    PubMed

    Campos-Giménez, Esther; Fontannaz, Patric; Redeuil, Karine; Kilinc, Tamara; Dowell, Dawn

    2013-01-01

    During the AOAC Annual Meeting held in Las Vegas, NV from September 30 to October 3, 2012, the Stakeholder Panel on Infant Formula and Adult Nutritionals convened to review single-laboratory validation data submitted for the method, Vitamin C in Adult/Pediatric Formula by Ultra-Performance Liquid Chromatography with Ultraviolet Detection. This method is a modified version of the method "HPLC-UV Determination of Total Vitamin C in a Wide Range of Fortified Food Products" previously published in Food Chem., 94, 626-631 (2006). The SLV data from the modified method were reviewed and compared to the standard method performance requirements (SMPR 2012.012), and it was concluded that the method meets the requirements. The method was approved as AOAC Official First Action. The method is based on the acidic extraction of ascorbic acid in the presence of Tris[2-carboxyethyl] phosphine (TCEP) as a reducing agent. Separation was achieved on a C18 column with a sodium acetate eluent (pH 5.4) combined with TCEP and decylamine as an ion-pairing agent. Accuracy rates were between 90 and 100%. Repeatability RSD (RSD,) ranged from 1.4 to 2.5%, and intermediate reproducibility RSD (RSDiR) ranged from 1.3 to 7.5%.

  14. Detection of BK virus DNA in nasopharyngeal aspirates from children with respiratory infections but not in saliva from immunodeficient and immunocompetent adult patients.

    PubMed Central

    Sundsfjord, A; Spein, A R; Lucht, E; Flaegstad, T; Seternes, O M; Traavik, T

    1994-01-01

    Our understanding of important stages in the pathogenesis of the human polyomavirus BK virus (BKV) and JC virus (JCV) infections is limited. In this context, nasopharyngeal aspirates from 201 children with respiratory diseases and saliva from 60 human immunodeficiency virus type 1-infected adults and 10 healthy adult controls were collected and analyzed for the presence of BKV and JCV DNA by PCR. Neither BKV nor JCV DNA was detected in the saliva specimens. We demonstrated BKV DNA, but no infectious BKV, in 2 of 201 nasopharyngeal aspirates. Each sample contained one unique rearranged noncoding control region variant of BKV. The results indicate that (i) BKV and JCV are not regularly associated with respiratory infections in children requiring hospitalization, (ii) nasopharyngeal cells are not an important site for primary replication of human polyomavirus BKV and JCV, and (iii) the salivary glands and oropharyngeal cells seem not to be involved in BKV and JCV persistence. We propose that for the polyomaviruses BKV and JCV the alimentary tract should be considered as a portal of entrance to the human organism. Images PMID:8051277

  15. Intra-Rater Reliability and Minimal Detectable Change of Vertical Ground Reaction Force Measurement during Gait and Half-Squat Tasks on Healthy Male Adults

    PubMed Central

    Fairus, Fariza Zainudin; Joseph, Leonard Henry; Omar, Baharudin; Ahmad, Johan; Sulaiman, Riza

    2016-01-01

    Background The understanding of vertical ground reaction force (VGRF) during walking and half-squatting is necessary and commonly utilised during the rehabilitation period. The purpose of this study was to establish measurement reproducibility of VGRF that reports the minimal detectable changes (MDC) during walking and half-squatting activity among healthy male adults. Methods 14 male adults of average age, 24.88 (5.24) years old, were enlisted in this study. The VGRF was assessed using the force plates which were embedded into a customised walking platform. Participants were required to carry out three trials of gait and half-squat. Each participant completed the two measurements within a day, approximately four hours apart. Results Measurements of VGRF between sessions presented an excellent VGRF data for walking (ICC Left = 0.88, ICC Right = 0.89). High reliability of VGRF was also noted during the half-squat activity (ICC Left = 0.95, ICC Right = 0.90). The standard errors of measurement (SEM) of VGRF during the walking and half-squat activity are less than 8.35 Nm/kg and 4.67 Nm/kg for the gait and half-squat task respectively. Conclusion The equipment set-up and measurement procedure used to quantify VGRF during walking and half-squatting among healthy males displayed excellent reliability. Researcher should consider using this method to measure the VGRF during functional performance assessment. PMID:27547111

  16. Association of Sand Dust Particles with Pulmonary Function and Respiratory Symptoms in Adult Patients with Asthma in Western Japan Using Light Detection and Ranging: A Panel Study

    PubMed Central

    Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Shimizu, Atsushi; Sano, Hiroyuki; Kato, Kazuhiro; Mikami, Masaaki; Ueda, Yasuto; Tatsukawa, Toshiyuki; Ohga, Hideki; Yamasaki, Akira; Igishi, Tadashi; Kitano, Hiroya; Shimizu, Eiji

    2015-01-01

    Light detection and ranging (LIDAR) can estimate daily volumes of sand dust particles from the East Asian desert to Japan. The objective of this study was to investigate the relationship between sand dust particles and pulmonary function, and respiratory symptoms in adult patients with asthma. One hundred thirty-seven patients were included in the study. From March 2013 to May 2013, the patients measured their morning peak expiratory flow (PEF) and kept daily lower respiratory symptom diaries. A linear mixed model was used to estimate the correlation of the median daily levels of sand dust particles, symptoms scores, and PEF. A heavy sand dust day was defined as an hourly concentration of sand dust particles of >0.1 km−1. By this criterion, there were 8 heavy sand dust days during the study period. Elevated sand dust particles levels were significantly associated with the symptom score (0.04; 95% confidence interval (CI); 0.03, 0.05), and this increase persisted for 5 days. There was no significant association between PEF and heavy dust exposure (0.01 L/min; 95% CI, −0.62, 0.11). The present study found that sand dust particles were significantly associated with worsened lower respiratory tract symptoms in adult patients with asthma, but not with pulmonary function. PMID:26501307

  17. Radiographic detection of thoracic lesions in adult cows: A retrospective study of 42 cases (1995–2002)

    PubMed Central

    Masseau, Isabelle; Fecteau, Gilles; Breton, Luc; Hélie, Pierre; Beauregard, Guy; Blond, Laurent

    2008-01-01

    Medical records of 42 cows that underwent both thoracic radiographic and postmortem examinations within a period of 7 days were reviewed to develop an evaluation grid to interpret bovine thoracic radiographs and to determine the sensitivity and the specificity of thoracic radiographs for detection of thoracic lesions, based on postmortem examination. Most cows (64%) had clinical signs of respiratory disease, whereas 19% showed signs of cardiac problems. The sensitivity and specificity of radiographs for identifying cows with thoracic lesions were 94% and 50%, respectively. In this study, with a prevalence of thoracic lesions of 86%, the positive- and negative-predictive values were 92% and 57%, respectively. This study provides an evaluation grid that allows standardization of the reading of bovine thoracic radiographs and the identification of most thoracic lesions. Bovine thoracic radiographs are useful in detecting thoracic lesions in cows. PMID:18390098

  18. Is it possible to use the honey bee adult as a bioindicator for the detection of pesticide residues in plants?

    PubMed

    Mansour, S A

    1987-01-01

    Pesticide residues are usually determined by physical, chemical and biological methods. The simplicity and adaptability of bioassay methods have won their acceptance in the field of residue analysis. Theoretically, any organism that is susceptible to a pesticide may be used for its bioassay in any environmental sample. This means that such organism may serve as a bioindicator for the detection of certain pollutants. The susceptibility of honey bees (Apis melifera L.) to many insecticides commonly used in crop protection led to an attempt to use it as a bioindicator for the determination of residues of some insecticides in plant materials, as well as to detect toxicity hazards to honey bees of some commonly used insecticides. Results of this work which have been recently published may suggest "Yes" to answer the question posed in the title of this subject.

  19. Determination of vitamin B12 in infant formula and adult nutritionals by liquid chromatography/UV detection with immunoaffinity extraction: First Action 2011.08.

    PubMed

    Campos-Giménez, Esther; Fontannaz, Patric; Trisconi, Marie-José; Kilinc, Tamara; Gimenez, Catherine; Andrieux, Pierre; Nelson, Maria

    2012-01-01

    At the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting," on June 29, 2011, an Expert Review Panel agreed that the method "Determination of Vitamin B12 in Infant Formulas and Adult Nutritionals by Liquid Chromatography/UV Detection with Immunoaffinity Extraction" be adopted AOAC Official First Action status. The method is applicable for the determination of vitamin B12, which includes added cyanocobalamin and natural forms, making it applicable to both fortified and nonfortified products. Vitamin B12 is extracted from the sample in sodium acetate buffer in the presence of sodium cyanide (100 degrees C, 30 min). After purification and concentration with an immunoaffinity column, vitamin B12 is determined by LC with UV detection (361 nm). A single-laboratory validation study was conducted on a range of products, including milk- and soy-based infant formulas, cereals, cocoa beverages, health care products, and polyvitamin premixes. The method demonstrated linear response over a large range of concentrations, recovery rates of 100.8 +/- 7.5% (average +/- SD), repeatability RSD (RSDr) of 2.1%, and intermediate reproducibility (RSD(iR)) of 4.3%. LOD and LOQ values were 0.10 and 0.30 microg/100 g, respectively, and correlation with the reference microbiological assay was good (R2 = 0.9442). The results of the study were published in J. AOAC Int. 91, 786-793 (2008). The performance characteristics of the method met the standard method performance requirements set forth by the Stakeholder Panel on Infant Formula and Adult Nutritionals; thus, the method was determined to be appropriate for First Action status. PMID:22649911

  20. Determination of vitamin B12 in infant formula and adult nutritionals by liquid chromatography/UV detection with immunoaffinity extraction: First Action 2011.08.

    PubMed

    Campos-Giménez, Esther; Fontannaz, Patric; Trisconi, Marie-José; Kilinc, Tamara; Gimenez, Catherine; Andrieux, Pierre; Nelson, Maria

    2012-01-01

    At the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting," on June 29, 2011, an Expert Review Panel agreed that the method "Determination of Vitamin B12 in Infant Formulas and Adult Nutritionals by Liquid Chromatography/UV Detection with Immunoaffinity Extraction" be adopted AOAC Official First Action status. The method is applicable for the determination of vitamin B12, which includes added cyanocobalamin and natural forms, making it applicable to both fortified and nonfortified products. Vitamin B12 is extracted from the sample in sodium acetate buffer in the presence of sodium cyanide (100 degrees C, 30 min). After purification and concentration with an immunoaffinity column, vitamin B12 is determined by LC with UV detection (361 nm). A single-laboratory validation study was conducted on a range of products, including milk- and soy-based infant formulas, cereals, cocoa beverages, health care products, and polyvitamin premixes. The method demonstrated linear response over a large range of concentrations, recovery rates of 100.8 +/- 7.5% (average +/- SD), repeatability RSD (RSDr) of 2.1%, and intermediate reproducibility (RSD(iR)) of 4.3%. LOD and LOQ values were 0.10 and 0.30 microg/100 g, respectively, and correlation with the reference microbiological assay was good (R2 = 0.9442). The results of the study were published in J. AOAC Int. 91, 786-793 (2008). The performance characteristics of the method met the standard method performance requirements set forth by the Stakeholder Panel on Infant Formula and Adult Nutritionals; thus, the method was determined to be appropriate for First Action status.

  1. Efficient and Specific Detection of Salmonella in Food Samples Using a stn-Based Loop-Mediated Isothermal Amplification Method

    PubMed Central

    Srisawat, Mevaree; Panbangred, Watanalai

    2015-01-01

    The Salmonella enterotoxin (stn) gene exhibits high homology among S. enterica serovars and S. bongori. A set of 6 specific primers targeting the stn gene were designed for detection of Salmonella spp. using the loop-mediated isothermal amplification (LAMP) method. The primers amplified target sequences in all 102 strains of 87 serovars of Salmonella tested and no products were detected in 57 non-Salmonella strains. The detection limit in pure cultures was 5 fg DNA/reaction when amplified at 65°C for 25 min. The LAMP assay could detect Salmonella in artificially contaminated food samples as low as 220 cells/g of food without a preenrichment step. However, the sensitivity was increased 100-fold (~2 cells/g) following 5 hr preenrichment at 35°C. The LAMP technique, with a preenrichment step for 5 and 16 hr, was shown to give 100% specificity with food samples compared to the reference culture method in which 67 out of 90 food samples gave positive results. Different food matrixes did not interfere with LAMP detection which employed a simple boiling method for DNA template preparation. The results indicate that the LAMP method, targeting the stn gene, has great potential for detection of Salmonella in food samples with both high specificity and high sensitivity. PMID:26543859

  2. Highly specific and efficient primers for in-house multiplex PCR detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum

    PubMed Central

    2014-01-01

    Background Although sophisticated methodologies are available, the use of endpoint polymerase chain reaction (PCR) to detect 16S rDNA genes remains a good approach for estimating the incidence and prevalence of specific infections and for monitoring infections. Considering the importance of the early diagnosis of sexually transmitted infections (STIs), the development of a sensitive and affordable method for identifying pathogens in clinical samples is needed. Highly specific and efficient primers for a multiplex polymerase chain reaction (m-PCR) system were designed in silico to detect the 16S rDNA genes of four bacteria that cause genital infections, and the PCR method was developed. Methods The Genosensor Probe Designer (GPD) (version 1.0a) software was initially used to design highly specific and efficient primers for in-house m-PCR. Single-locus PCR reactions were performed and standardised, and then primers for each locus in turn were added individually in subsequent amplifications until m-PCR was achieved. Amplicons of the expected size were obtained from each of the four bacterial gene fragments. Finally, the analytical specificity and limits of detection were tested. Results Because they did not amplify any product from non-STI tested species, the primers were specific. The detection limits for the Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum primer sets were 5.12 × 105, 3.9 × 103, 61.19 × 106 and 6.37 × 105 copies of a DNA template, respectively. Conclusions The methodology designed and standardised here could be applied satisfactorily for the simultaneous or individual detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum. This method is at least as efficient as other previously described methods; however, this method is more affordable for low-income countries. PMID:24997675

  3. DETECTORS AND EXPERIMENTAL METHODS: Measurement of the response function and the detection efficiency of an organic liquid scintillator for neutrons between 1 and 30 MeV

    NASA Astrophysics Data System (ADS)

    Huang, Han-Xiong; Ruan, Xi-Chao; Chen, Guo-Chang; Zhou, Zu-Ying; Li, Xia; Bao, Jie; Nie, Yang-Bo; Zhong, Qi-Ping

    2009-08-01

    The light output function of a varphi50.8 mm × 50.8 mm BC501A scintillation detector was measured in the neutron energy region of 1 to 30 MeV by fitting the pulse height (PH) spectra for neutrons with the simulations from the NRESP code at the edge range. Using the new light output function, the neutron detection efficiency was determined with two Monte-Carlo codes, NEFF and SCINFUL. The calculated efficiency was corrected by comparing the simulated PH spectra with the measured ones. The determined efficiency was verified at the near threshold region and normalized with a Proton-Recoil-Telescope (PRT) at the 8-14 MeV energy region.

  4. Increase in myeloid-derived suppressor cells (MDSCs) associated with minimal residual disease (MRD) detection in adult acute myeloid leukemia.

    PubMed

    Sun, Hui; Li, Yi; Zhang, Zhi-fen; Ju, Ying; Li, Li; Zhang, Bing-chang; Liu, Bin

    2015-11-01

    Myeloid-derived suppressor cells (MDSCs) are thought to help provide a cellular microenvironments in many solid tumors, in which transformed cells proliferate, acquire new mutations, and evade host immunosurveillance. In the present study, we found that MDSCs (CD33 + CD11b + HLA-DR(low/neg)) in bone marrow were significantly increased in adult acute myeloid leukemia (AML) patients. MDSCs levels in newly diagnosed AML patients correlated well with extramedullary infiltration and plasma D-dimer levels. Remission rates in the MDSCs > 1500 group and MDSCs < 1500 group were 72.73 and 81.25 %, respectively. No significant differences were found between the two groups. MDSC levels in the complete remission group were significantly decreased after chemotherapy, while in the partial remission and non-remission groups, there were no significant differences. The level of MDSCs in the high minimal residual disease (MRD) group was significantly higher than that in the middle and low MRD groups. High levels of Wilms' Tumor-1 (WT-1) protein were strongly correlated with higher bone marrow MDSC levels. In conclusion, we report here a population of immunosuppressive monocytes in the bone marrow of patients with AML characterized by the CD33(high)CD11b + HLA-DR(low/neg) phenotype. These cells appear to impact the clinical course and prognosis of AML. This data may provide potentially important targets for novel therapies.

  5. Biofunctionalized magnetic nanospheres-based cell sorting strategy for efficient isolation, detection and subtype analyses of heterogeneous circulating hepatocellular carcinoma cells.

    PubMed

    Chen, Lan; Wu, Ling-Ling; Zhang, Zhi-Ling; Hu, Jiao; Tang, Man; Qi, Chu-Bo; Li, Na; Pang, Dai-Wen

    2016-11-15

    Hepatocellular carcinoma (HCC) is an awful threat to human health. Early-stage HCC may be detected by isolation of circulating tumor cells (CTCs) from peripheral blood samples, which is beneficial to the diagnosis and therapy. However, the extreme rarity and high heterogeneity of HCC CTCs have been restricting the relevant research. To achieve an efficient isolation, reliable detection and subtype analyses of heterogeneous HCC CTCs, herein, we present a cell sorting strategy based on anti-CD45 antibody-modified magnetic nanospheres. By this strategy, leukocyte depletion efficiency was up to 99.9% within 30min in mimic clinical samples, and the purity of the spiked HCC cells was improved 265-317-fold. Besides, the isolated HCC cells remained viable at 92.3% and could be directly recultured. Moreover, coupling the convenient, fast and effective cell sorting strategy with specific ICC identification via biomarkers AFP and GPC3, HCC CTCs were detectable in peripheral blood samples, showing the potential for HCC CTC detection in clinic. Notably, this immunomagnetic cell sorting strategy enabled isolating more heterogeneous HCC cells compared with the established EpCAM-based methods, and further achieved characterization of three different CTC subtypes from one clinical HCC blood sample, which may assist clinical HCC analyses such as prognosis or personalized treatment. PMID:27240010

  6. Successful detection of (anti-)androgenic and aromatase inhibitors in pre-spawning adult fathead minnows (Pimephales promelas) using easily measured endpoints of sexual development.

    PubMed

    Panter, G H; Hutchinson, T H; Hurd, K S; Sherren, A; Stanley, R D; Tyler, C R

    2004-10-18

    Screening assays have been successfully developed for the detection of (anti-)oestrogenic substances in several fish species, including the fathead minnow (Pimephales promelas). Previous work suggested that pre-spawning adult fathead minnows might be an appropriate life-stage for developing a screen to detect endocrine active substances (EASs). Pre-spawning adult fathead minnows, in which their phenotypic sex could be determined, were exposed in flow-through systems to three reference substances for 21 days, at 25 degrees C. Male and female fish, held in separate tanks, were exposed to dihydrotestosterone (DHT, androgen), flutamide (anti-androgen) and fadrozole (aromatase inhibitor). Nominal (mean measured) concentrations for DHT were 10 (6.0), 32 (6.1) and 100 (8.6) microg l(-1), for flutamide, 100 (95.3), 320 (320.4) and 1000 (938.6) microg l(-1) and for fadrozole, 25 (24.8), 50 (51.7) and 100 (95.5) microg l(-1). After 14 and 21 days exposure, fish were evaluated for growth, secondary sexual characteristics (SSCs, number and prominence of nuptial tubercles), gonadosomatic index (GSI) and plasma vitellogenin (VTG) concentrations. Development of nuptial tubercles was sensitive to both DHT and flutamide exposure. Exposure to DHT significantly increased the number of nuptial tubercles (male characteristic) in both males (more abundant) and females, after 14 days. Flutamide (938.6 microg l(-1), day 21) significantly reduced nuptial tubercle number in male fish. Fadrozole significantly inhibited ovarian growth (lower GSI) and significantly induced testis growth (51.7 and 95.5 microg l(-1)), after 21 days. Plasma VTG concentrations were significantly elevated in male fish (6.1 and 8.6 microg l(-1)), but inhibited in female fish (6.0 microg l(-1)), exposed to DHT. Flutamide had no effect on plasma VTG in male fish, but significantly induced VTG in female fish, after 21 days. Fadrozole significantly inhibited VTG in females and induced VTG synthesis in males, at day 21

  7. Multi-wavelength resonant pumping of Er:YAG lasers for energy efficient trace gas detection systems

    NASA Astrophysics Data System (ADS)

    Fritsche, Haro; Lux, Oliver; Schuett, Casey; Gaertner, Martin; Juhre, Ronny; Grohe, Andreas; Gries, Wolfgang; Eichler, Hans J.

    2015-02-01

    The multiplicity of narrow absorption lines of erbium ions in the spectral range from 1450 to 1540 nm is exploited for the development of a highly efficient Er:YAG laser emitting at 1645 nm. Resonant pumping of the active medium with an absorption efficiency of up to 96% is achieved using a novel diode laser system consisting of two narrowband modules with a combined output power of 80 W ex fiber. The utilization of multiple pump wavelengths allows for both substantial power scaling and reduction of the laser threshold, thus providing a low power consuming laser system feasible for LIDAR applications.

  8. A simple but highly efficient multi-formyl phenol-amine system for fluorescence detection of peroxide explosive vapour.

    PubMed

    Xu, Wei; Fu, Yanyan; Gao, Yixun; Yao, Junjun; Fan, Tianchi; Zhu, Defeng; He, Qingguo; Cao, Huimin; Cheng, Jiangong

    2015-07-11

    A simple, highly stable, sensitive and selective fluorescent system for peroxide explosives was developed via an aromatic aldehyde oxidation reaction. The high efficiency arises from its higher HOMO level and multiple H-bonding. The sensitivity is obtained to be 0.1 ppt for H2O2 and 0.2 ppb for TATP. PMID:26054635

  9. Pilot simulation study using meat inspection data for syndromic surveillance: use of whole carcass condemnation of adult cattle to assess the performance of several algorithms for outbreak detection.

    PubMed

    Dupuy, C; Morignat, E; Dorea, F; Ducrot, C; Calavas, D; Gay, E

    2015-09-01

    The objective of this study was to assess the performance of several algorithms for outbreak detection based on weekly proportions of whole carcass condemnations. Data from one French slaughterhouse over the 2005-2009 period were used (177 098 slaughtered cattle, 0.97% of whole carcass condemnations). The method involved three steps: (i) preparation of an outbreak-free historical baseline over 5 years, (ii) simulation of over 100 years of baseline time series with injection of artificial outbreak signals with several shapes, durations and magnitudes, and (iii) assessment of the performance (sensitivity, specificity, outbreak detection precocity) of several algorithms to detect these artificial outbreak signals. The algorithms tested included the Shewart p chart, confidence interval of the negative binomial model, the exponentially weighted moving average (EWMA); and cumulative sum (CUSUM). The highest sensitivity was obtained using a negative binomial algorithm and the highest specificity with CUSUM or EWMA. EWMA sensitivity was too low to select this algorithm for efficient outbreak detection. CUSUM's performance was complementary to the negative binomial algorithm. The use of both algorithms on real data for a prospective investigation of the whole carcass condemnation rate as a syndromic surveillance indicator could be relevant. Shewart could also be a good option considering its high sensitivity and simplicity of implementation.

  10. Adult Books for Young Adults.

    ERIC Educational Resources Information Center

    Carter, Betty

    1997-01-01

    Considers the differences between young adult and adult books and maintains that teachers must be familiar with young adults' tastes for both. Suggests that traffic between these publishing divisions is a two-way street, with young adults reading adult books and adults reading young adult books. (TB)

  11. Impact of rapid antigen detection testing on antibiotic prescription in acute pharyngitis in adults. FARINGOCAT STUDY: a multicentric randomized controlled trial

    PubMed Central

    2010-01-01

    Background Acute pharyngitis is one of the most frequent consultations to the general practitioner and in most of the cases an antibiotic is prescribed in primary care in Spain. Bacterial etiology, mainly by group A beta-hemolytic streptococcus (GABHS), accounts for 10-20% of all these infections in adults. The purpose of this study is to assess the impact of rapid antigen detection testing (RADT) to identify GABHS in acute pharyngitis on the utilization of antibiotics in primary care. Methods/design Multicentric randomized controlled trial in which antibiotic prescription between two groups of patients with acute pharyngitis will be compared. The trial will include two arms, a control and an intervention group in which RADT will be performed. The primary outcome measure will be the proportion of inappropriate antibiotic prescription in each group. Two hundred seventy-six patients are required to detect a reduction in antibiotic prescription from 85% in the control group to 75% in the intervention group with a power of 90% and a level of significance of 5%. Secondary outcome measures will be specific antibiotic treatment, antibiotic resistance rates, secondary effects, days without working, medical visits during the first month and patient satisfaction. Discussion The implementation of RADT would allow a more rational use of antibiotics and would prevent adverse effects of antibiotics, emergence of antibiotic resistance and the growth of inefficient health expenses. Trial registration ISRCTN23587778 PMID:20331895

  12. Dithizone as novel and efficient chromogenic probe for cyanide detection in aqueous media through nucleophilic addition into diazenylthione moiety.

    PubMed

    Tavallali, Hossein; Deilamy-Rad, Gohar; Parhami, Abolfath; Kiyani, Sajede

    2014-01-01

    A new selective chemodosimeter probe was developed by the introduction of dithizone (DTZ) as a simple and available dye for detection of cyanide in aqueous media which enables recognition of cyanide over other competing anions such as acetate, dihydrogen phosphate, fluoride and benzoate through covalent bonding. The sensing properties of DTZ were investigated in DMSO/H2O (1:9) and have demonstrated a very high selectivity toward the cyanide anions. A reasonable recognition mechanism was suggested using UV-Vis, (1)H NMR and FTIR spectroscopy techniques. Time dependent density function theory (TDDFT) computations of UV-Vis excitation for DTZ2-CN adduct agreed well with our experimental findings. The detection limit of the new chromogenic probe was measured to be 0.48 μmol L(-1) which is much lower than most recently reported chromogenic probes for cyanide determination. The an